User login
Blood cells emerge through internal struggle, study suggests
Image by Volker Brinkmann
Developing blood cells are caught in a tug of war between competing gene regulatory networks before finally deciding what type of cell to become, according to a study published in Nature.
Researchers found that, as developing blood cells are triggered by a multitude of genetic signals firing on and off, they are pulled back and forth in fluctuating multi-lineage states before finally becoming specific cell types.
The team still doesn’t understand exactly what drives the cells to an eventual fate, but their work suggests that competing gene networks induce dynamic instability, resulting in mixed-lineage states that are necessary to prime newly forming cells for that decision.
“It is somewhat chaotic, but, from that chaos, results order,” said study author Harinder Singh, PhD, of Cincinnati Children’s Hospital Medical Center in Ohio.
“It’s a finding that helps us address a fundamental question of developmental biology: What are the nature of the intermediate states and the networks of regulatory genes that underlie cell-type specification?”
Although the finding requires additional study to better understand the back-and-forth nature of this process, the research may eventually provide new insights into developmental miscues that cause disease, according to study author H. Leighton Grimes, PhD, of Cincinnati Children’s.
“How do blood cells know to become neutrophils or monocytes?” Dr Grimes asked. “Two thirds of your bone marrow is taken up with this activity, and the number of cells has to be exquisitely balanced. Too many or too few of either can kill you.”
For this study, Dr Grimes and his colleagues looked specifically at the formation of neutrophils and macrophages. The researchers studied mouse cells as they developed in a natural state using single-cell RNA sequencing.
The team also used a bioinformatics computer program known as iterative clustering and guide-gene selection (ICGS). They used ICGS to process and analyze sequencing and biological data to identify the various transitioning or shifting genomic and cellular states of developing blood cells.
Dynamic instability
Researchers previously proposed that neutrophils and macrophages result from a bi-stable gene regulatory network—one that can manifest either of 2 stable states. But the different cellular transition states and underlying molecular dynamics of development have remained unknown.
Dr Grimes and his colleagues said their analysis of developing blood cells captured a prevalent mixed-lineage intermediate.
These intermediates expressed a combination of genes, including those typical of hematopoietic stem and progenitor cells and some genes that are specific for red blood cells, platelets, macrophages, and neutrophils. This seemed to reflect competing genetic programs.
The researchers also observed the developing cells moving through a rare state where they encountered turbulence known as dynamic instability. This was caused by 2 counteracting myeloid gene regulatory networks.
Two key components of the counteracting gene networks were Irf8 and Gfi1, genes that are involved in blood cell formation. When Irf8 and Gfi1 were eliminated from the picture, the rare cells could be trapped in an intermediate state.
As they continue this work, the researchers want to gain a clearer understanding of what finally causes cells in intermediate states of dynamic instability to assume specific fates.
The team suggests the influence of 2 simultaneous and counteracting gene networks generates internal oscillations that are eventually stabilized by unknown mechanisms to generate 1 of 2 different cell fates. 
Image by Volker Brinkmann
Developing blood cells are caught in a tug of war between competing gene regulatory networks before finally deciding what type of cell to become, according to a study published in Nature.
Researchers found that, as developing blood cells are triggered by a multitude of genetic signals firing on and off, they are pulled back and forth in fluctuating multi-lineage states before finally becoming specific cell types.
The team still doesn’t understand exactly what drives the cells to an eventual fate, but their work suggests that competing gene networks induce dynamic instability, resulting in mixed-lineage states that are necessary to prime newly forming cells for that decision.
“It is somewhat chaotic, but, from that chaos, results order,” said study author Harinder Singh, PhD, of Cincinnati Children’s Hospital Medical Center in Ohio.
“It’s a finding that helps us address a fundamental question of developmental biology: What are the nature of the intermediate states and the networks of regulatory genes that underlie cell-type specification?”
Although the finding requires additional study to better understand the back-and-forth nature of this process, the research may eventually provide new insights into developmental miscues that cause disease, according to study author H. Leighton Grimes, PhD, of Cincinnati Children’s.
“How do blood cells know to become neutrophils or monocytes?” Dr Grimes asked. “Two thirds of your bone marrow is taken up with this activity, and the number of cells has to be exquisitely balanced. Too many or too few of either can kill you.”
For this study, Dr Grimes and his colleagues looked specifically at the formation of neutrophils and macrophages. The researchers studied mouse cells as they developed in a natural state using single-cell RNA sequencing.
The team also used a bioinformatics computer program known as iterative clustering and guide-gene selection (ICGS). They used ICGS to process and analyze sequencing and biological data to identify the various transitioning or shifting genomic and cellular states of developing blood cells.
Dynamic instability
Researchers previously proposed that neutrophils and macrophages result from a bi-stable gene regulatory network—one that can manifest either of 2 stable states. But the different cellular transition states and underlying molecular dynamics of development have remained unknown.
Dr Grimes and his colleagues said their analysis of developing blood cells captured a prevalent mixed-lineage intermediate.
These intermediates expressed a combination of genes, including those typical of hematopoietic stem and progenitor cells and some genes that are specific for red blood cells, platelets, macrophages, and neutrophils. This seemed to reflect competing genetic programs.
The researchers also observed the developing cells moving through a rare state where they encountered turbulence known as dynamic instability. This was caused by 2 counteracting myeloid gene regulatory networks.
Two key components of the counteracting gene networks were Irf8 and Gfi1, genes that are involved in blood cell formation. When Irf8 and Gfi1 were eliminated from the picture, the rare cells could be trapped in an intermediate state.
As they continue this work, the researchers want to gain a clearer understanding of what finally causes cells in intermediate states of dynamic instability to assume specific fates.
The team suggests the influence of 2 simultaneous and counteracting gene networks generates internal oscillations that are eventually stabilized by unknown mechanisms to generate 1 of 2 different cell fates.
Image by Volker Brinkmann
Developing blood cells are caught in a tug of war between competing gene regulatory networks before finally deciding what type of cell to become, according to a study published in Nature.
Researchers found that, as developing blood cells are triggered by a multitude of genetic signals firing on and off, they are pulled back and forth in fluctuating multi-lineage states before finally becoming specific cell types.
The team still doesn’t understand exactly what drives the cells to an eventual fate, but their work suggests that competing gene networks induce dynamic instability, resulting in mixed-lineage states that are necessary to prime newly forming cells for that decision.
“It is somewhat chaotic, but, from that chaos, results order,” said study author Harinder Singh, PhD, of Cincinnati Children’s Hospital Medical Center in Ohio.
“It’s a finding that helps us address a fundamental question of developmental biology: What are the nature of the intermediate states and the networks of regulatory genes that underlie cell-type specification?”
Although the finding requires additional study to better understand the back-and-forth nature of this process, the research may eventually provide new insights into developmental miscues that cause disease, according to study author H. Leighton Grimes, PhD, of Cincinnati Children’s.
“How do blood cells know to become neutrophils or monocytes?” Dr Grimes asked. “Two thirds of your bone marrow is taken up with this activity, and the number of cells has to be exquisitely balanced. Too many or too few of either can kill you.”
For this study, Dr Grimes and his colleagues looked specifically at the formation of neutrophils and macrophages. The researchers studied mouse cells as they developed in a natural state using single-cell RNA sequencing.
The team also used a bioinformatics computer program known as iterative clustering and guide-gene selection (ICGS). They used ICGS to process and analyze sequencing and biological data to identify the various transitioning or shifting genomic and cellular states of developing blood cells.
Dynamic instability
Researchers previously proposed that neutrophils and macrophages result from a bi-stable gene regulatory network—one that can manifest either of 2 stable states. But the different cellular transition states and underlying molecular dynamics of development have remained unknown.
Dr Grimes and his colleagues said their analysis of developing blood cells captured a prevalent mixed-lineage intermediate.
These intermediates expressed a combination of genes, including those typical of hematopoietic stem and progenitor cells and some genes that are specific for red blood cells, platelets, macrophages, and neutrophils. This seemed to reflect competing genetic programs.
The researchers also observed the developing cells moving through a rare state where they encountered turbulence known as dynamic instability. This was caused by 2 counteracting myeloid gene regulatory networks.
Two key components of the counteracting gene networks were Irf8 and Gfi1, genes that are involved in blood cell formation. When Irf8 and Gfi1 were eliminated from the picture, the rare cells could be trapped in an intermediate state.
As they continue this work, the researchers want to gain a clearer understanding of what finally causes cells in intermediate states of dynamic instability to assume specific fates.
The team suggests the influence of 2 simultaneous and counteracting gene networks generates internal oscillations that are eventually stabilized by unknown mechanisms to generate 1 of 2 different cell fates.
FDA approves new indication for ofatumumab in CLL
Photo courtesy of GSK
The US Food and Drug Administration (FDA) has approved the use of ofatumumab (Arzerra®) in combination with fludarabine and cyclophosphamide to treat patients with relapsed chronic lymphocytic leukemia (CLL).
Ofatumumab was previously approved by the FDA for use in combination with chlorambucil to treat previously untreated CLL patients who cannot receive fludarabine-based therapy, as monotherapy for CLL that is refractory to fludarabine and alemtuzumab, and as maintenance therapy for patients who are in complete or partial response after receiving at least 2 lines of therapy for recurrent or progressive CLL.
Ofatumumab is a monoclonal antibody designed to target CD20.
The drug’s prescribing information includes a boxed warning noting that hepatitis B virus reactivation can occur in patients receiving CD20-directed cytolytic antibodies, including ofatumumab. In some cases, this results in fulminant hepatitis, hepatic failure, and death.
The boxed warning also states that progressive multifocal leukoencephalopathy, resulting in death, can occur in patients receiving CD20-directed cytolytic antibodies, including ofatumumab.
Ofatumumab is marketed under a collaboration agreement between Genmab and Novartis.
COMPLEMENT 2 trial
The FDA’s latest approval for ofatumumab is based on results of the phase 3 COMPLEMENT 2 trial. Novartis reported top-line results from this study in April.
The trial enrolled 365 patients with relapsed CLL. The patients were randomized 1:1 to receive up to 6 cycles of ofatumumab in combination with fludarabine and cyclophosphamide or up to 6 cycles of fludarabine and cyclophosphamide alone.
The primary endpoint was progression-free survival, as assessed by an independent review committee.
The median progression-free survival was 28.9 months for patients receiving ofatumumab plus fludarabine and cyclophosphamide, compared to 18.8 months for patients receiving fludarabine and cyclophosphamide alone (hazard ratio=0.67, P=0.0032).
Novartis said the safety profile observed in this study was consistent with other trials of ofatumumab, and no new safety signals were observed.
Photo courtesy of GSK
The US Food and Drug Administration (FDA) has approved the use of ofatumumab (Arzerra®) in combination with fludarabine and cyclophosphamide to treat patients with relapsed chronic lymphocytic leukemia (CLL).
Ofatumumab was previously approved by the FDA for use in combination with chlorambucil to treat previously untreated CLL patients who cannot receive fludarabine-based therapy, as monotherapy for CLL that is refractory to fludarabine and alemtuzumab, and as maintenance therapy for patients who are in complete or partial response after receiving at least 2 lines of therapy for recurrent or progressive CLL.
Ofatumumab is a monoclonal antibody designed to target CD20.
The drug’s prescribing information includes a boxed warning noting that hepatitis B virus reactivation can occur in patients receiving CD20-directed cytolytic antibodies, including ofatumumab. In some cases, this results in fulminant hepatitis, hepatic failure, and death.
The boxed warning also states that progressive multifocal leukoencephalopathy, resulting in death, can occur in patients receiving CD20-directed cytolytic antibodies, including ofatumumab.
Ofatumumab is marketed under a collaboration agreement between Genmab and Novartis.
COMPLEMENT 2 trial
The FDA’s latest approval for ofatumumab is based on results of the phase 3 COMPLEMENT 2 trial. Novartis reported top-line results from this study in April.
The trial enrolled 365 patients with relapsed CLL. The patients were randomized 1:1 to receive up to 6 cycles of ofatumumab in combination with fludarabine and cyclophosphamide or up to 6 cycles of fludarabine and cyclophosphamide alone.
The primary endpoint was progression-free survival, as assessed by an independent review committee.
The median progression-free survival was 28.9 months for patients receiving ofatumumab plus fludarabine and cyclophosphamide, compared to 18.8 months for patients receiving fludarabine and cyclophosphamide alone (hazard ratio=0.67, P=0.0032).
Novartis said the safety profile observed in this study was consistent with other trials of ofatumumab, and no new safety signals were observed.
Photo courtesy of GSK
The US Food and Drug Administration (FDA) has approved the use of ofatumumab (Arzerra®) in combination with fludarabine and cyclophosphamide to treat patients with relapsed chronic lymphocytic leukemia (CLL).
Ofatumumab was previously approved by the FDA for use in combination with chlorambucil to treat previously untreated CLL patients who cannot receive fludarabine-based therapy, as monotherapy for CLL that is refractory to fludarabine and alemtuzumab, and as maintenance therapy for patients who are in complete or partial response after receiving at least 2 lines of therapy for recurrent or progressive CLL.
Ofatumumab is a monoclonal antibody designed to target CD20.
The drug’s prescribing information includes a boxed warning noting that hepatitis B virus reactivation can occur in patients receiving CD20-directed cytolytic antibodies, including ofatumumab. In some cases, this results in fulminant hepatitis, hepatic failure, and death.
The boxed warning also states that progressive multifocal leukoencephalopathy, resulting in death, can occur in patients receiving CD20-directed cytolytic antibodies, including ofatumumab.
Ofatumumab is marketed under a collaboration agreement between Genmab and Novartis.
COMPLEMENT 2 trial
The FDA’s latest approval for ofatumumab is based on results of the phase 3 COMPLEMENT 2 trial. Novartis reported top-line results from this study in April.
The trial enrolled 365 patients with relapsed CLL. The patients were randomized 1:1 to receive up to 6 cycles of ofatumumab in combination with fludarabine and cyclophosphamide or up to 6 cycles of fludarabine and cyclophosphamide alone.
The primary endpoint was progression-free survival, as assessed by an independent review committee.
The median progression-free survival was 28.9 months for patients receiving ofatumumab plus fludarabine and cyclophosphamide, compared to 18.8 months for patients receiving fludarabine and cyclophosphamide alone (hazard ratio=0.67, P=0.0032).
Novartis said the safety profile observed in this study was consistent with other trials of ofatumumab, and no new safety signals were observed.
Team uncovers potential treatments for Zika virus
Photo courtesy of
Muhammad Mahdi Karim
Researchers say they have identified compounds that might be used to inhibit Zika virus replication and reduce the ability of the virus to kill brain cells.
The compounds include emricasan (a drug being investigated as a treatment to reduce liver damage from hepatitis C virus), niclosamide (a drug approved in the US to combat parasitic infections), and an investigational cyclin-dependent kinase inhibitor known as PHA-690509.
The researchers described the anti-Zika activity of these compounds in Nature Medicine.
About the virus
The Zika virus has been reported in 60 countries and territories worldwide. Currently, there are no vaccines or effective treatments for the virus.
Research and anecdotal evidence have suggested infection with the Zika virus is related to fetal microcephaly, an abnormally small head resulting from an underdeveloped and/or damaged brain. The virus has also been linked with neurological diseases such as Guillain-Barré syndrome in infected adults.
The Zika virus is spread primarily through bites from infected Aedes aegypti mosquitoes, but it can also be transmitted from mother to child, through sexual contact, via blood transfusion, and possibly through other methods.
“The Zika virus poses a global health threat,” said study author Anton Simeonov, PhD, of the National Center for Advancing Translational Sciences in Bethesda, Maryland.
“While we await the development of effective vaccines, which can take a significant amount of time, our identification of repurposed small-molecule compounds may accelerate the translational process of finding a potential therapy.”
“It takes years, if not decades, to develop a new drug,” noted study author Hongjun Song, PhD, of Johns Hopkins University School of Medicine in Baltimore, Maryland. “In this sort of global health emergency, we don’t have that kind of time.”
“So instead of using new drugs, we chose to screen existing drugs,” added Guo-li Ming, MD, PhD, also of Johns Hopkins. “In this way, we hope to create a therapy much more quickly.”
Identifying potential treatments
The researchers screened 6000 compounds, both investigational and approved (in the US), looking for drugs that might be effective against the Zika virus.
The team first exposed cell cultures to 3 strains of the virus—Ugandan, Cambodian, and Puerto Rican. Then, they introduced the various compounds and looked for indicators of cell death.
The researchers identified more than 100 promising compounds. The 3 lead compounds were emricasan, niclosamide, and PHA-690509.
These compounds were effective either in inhibiting the replication of Zika or in preventing the virus from killing brain cells. Emricasan prevents cell death, while niclosamide and PHA-690509 stop virus replication.
The researchers found that combining emricasan and PHA-690509 prevented both cell death and virus replication.
Dr Song cautioned that the 3 drugs “are very effective against Zika in the dish, but we don’t know if they can work in humans in the same way.”
For example, he noted that, although niclosamide can safely treat parasites in the human gastrointestinal tract, researchers have not yet determined if the drug can penetrate the central nervous system of adults or a fetus inside a carrier’s womb to treat the brain cells targeted by Zika.
Furthermore, it’s not clear if the drugs would address the wide range of effects of Zika infection.
“To address these questions, additional studies need to be done in animal models as well as humans to demonstrate their ability to treat Zika infection,” Dr Ming said. “So we could still be years away from finding a treatment that works.”
Photo courtesy of
Muhammad Mahdi Karim
Researchers say they have identified compounds that might be used to inhibit Zika virus replication and reduce the ability of the virus to kill brain cells.
The compounds include emricasan (a drug being investigated as a treatment to reduce liver damage from hepatitis C virus), niclosamide (a drug approved in the US to combat parasitic infections), and an investigational cyclin-dependent kinase inhibitor known as PHA-690509.
The researchers described the anti-Zika activity of these compounds in Nature Medicine.
About the virus
The Zika virus has been reported in 60 countries and territories worldwide. Currently, there are no vaccines or effective treatments for the virus.
Research and anecdotal evidence have suggested infection with the Zika virus is related to fetal microcephaly, an abnormally small head resulting from an underdeveloped and/or damaged brain. The virus has also been linked with neurological diseases such as Guillain-Barré syndrome in infected adults.
The Zika virus is spread primarily through bites from infected Aedes aegypti mosquitoes, but it can also be transmitted from mother to child, through sexual contact, via blood transfusion, and possibly through other methods.
“The Zika virus poses a global health threat,” said study author Anton Simeonov, PhD, of the National Center for Advancing Translational Sciences in Bethesda, Maryland.
“While we await the development of effective vaccines, which can take a significant amount of time, our identification of repurposed small-molecule compounds may accelerate the translational process of finding a potential therapy.”
“It takes years, if not decades, to develop a new drug,” noted study author Hongjun Song, PhD, of Johns Hopkins University School of Medicine in Baltimore, Maryland. “In this sort of global health emergency, we don’t have that kind of time.”
“So instead of using new drugs, we chose to screen existing drugs,” added Guo-li Ming, MD, PhD, also of Johns Hopkins. “In this way, we hope to create a therapy much more quickly.”
Identifying potential treatments
The researchers screened 6000 compounds, both investigational and approved (in the US), looking for drugs that might be effective against the Zika virus.
The team first exposed cell cultures to 3 strains of the virus—Ugandan, Cambodian, and Puerto Rican. Then, they introduced the various compounds and looked for indicators of cell death.
The researchers identified more than 100 promising compounds. The 3 lead compounds were emricasan, niclosamide, and PHA-690509.
These compounds were effective either in inhibiting the replication of Zika or in preventing the virus from killing brain cells. Emricasan prevents cell death, while niclosamide and PHA-690509 stop virus replication.
The researchers found that combining emricasan and PHA-690509 prevented both cell death and virus replication.
Dr Song cautioned that the 3 drugs “are very effective against Zika in the dish, but we don’t know if they can work in humans in the same way.”
For example, he noted that, although niclosamide can safely treat parasites in the human gastrointestinal tract, researchers have not yet determined if the drug can penetrate the central nervous system of adults or a fetus inside a carrier’s womb to treat the brain cells targeted by Zika.
Furthermore, it’s not clear if the drugs would address the wide range of effects of Zika infection.
“To address these questions, additional studies need to be done in animal models as well as humans to demonstrate their ability to treat Zika infection,” Dr Ming said. “So we could still be years away from finding a treatment that works.”
Photo courtesy of
Muhammad Mahdi Karim
Researchers say they have identified compounds that might be used to inhibit Zika virus replication and reduce the ability of the virus to kill brain cells.
The compounds include emricasan (a drug being investigated as a treatment to reduce liver damage from hepatitis C virus), niclosamide (a drug approved in the US to combat parasitic infections), and an investigational cyclin-dependent kinase inhibitor known as PHA-690509.
The researchers described the anti-Zika activity of these compounds in Nature Medicine.
About the virus
The Zika virus has been reported in 60 countries and territories worldwide. Currently, there are no vaccines or effective treatments for the virus.
Research and anecdotal evidence have suggested infection with the Zika virus is related to fetal microcephaly, an abnormally small head resulting from an underdeveloped and/or damaged brain. The virus has also been linked with neurological diseases such as Guillain-Barré syndrome in infected adults.
The Zika virus is spread primarily through bites from infected Aedes aegypti mosquitoes, but it can also be transmitted from mother to child, through sexual contact, via blood transfusion, and possibly through other methods.
“The Zika virus poses a global health threat,” said study author Anton Simeonov, PhD, of the National Center for Advancing Translational Sciences in Bethesda, Maryland.
“While we await the development of effective vaccines, which can take a significant amount of time, our identification of repurposed small-molecule compounds may accelerate the translational process of finding a potential therapy.”
“It takes years, if not decades, to develop a new drug,” noted study author Hongjun Song, PhD, of Johns Hopkins University School of Medicine in Baltimore, Maryland. “In this sort of global health emergency, we don’t have that kind of time.”
“So instead of using new drugs, we chose to screen existing drugs,” added Guo-li Ming, MD, PhD, also of Johns Hopkins. “In this way, we hope to create a therapy much more quickly.”
Identifying potential treatments
The researchers screened 6000 compounds, both investigational and approved (in the US), looking for drugs that might be effective against the Zika virus.
The team first exposed cell cultures to 3 strains of the virus—Ugandan, Cambodian, and Puerto Rican. Then, they introduced the various compounds and looked for indicators of cell death.
The researchers identified more than 100 promising compounds. The 3 lead compounds were emricasan, niclosamide, and PHA-690509.
These compounds were effective either in inhibiting the replication of Zika or in preventing the virus from killing brain cells. Emricasan prevents cell death, while niclosamide and PHA-690509 stop virus replication.
The researchers found that combining emricasan and PHA-690509 prevented both cell death and virus replication.
Dr Song cautioned that the 3 drugs “are very effective against Zika in the dish, but we don’t know if they can work in humans in the same way.”
For example, he noted that, although niclosamide can safely treat parasites in the human gastrointestinal tract, researchers have not yet determined if the drug can penetrate the central nervous system of adults or a fetus inside a carrier’s womb to treat the brain cells targeted by Zika.
Furthermore, it’s not clear if the drugs would address the wide range of effects of Zika infection.
“To address these questions, additional studies need to be done in animal models as well as humans to demonstrate their ability to treat Zika infection,” Dr Ming said. “So we could still be years away from finding a treatment that works.”
FDA authorizes use of test to detect Zika virus
Photo by Graham Colm
The US Food and Drug Administration (FDA) has issued an emergency use authorization (EUA) for the LightMix® Zika rRT-PCR Test.
The test, distributed by Roche, is used to detect the Zika virus in EDTA plasma or serum samples.
The LightMix® Zika rRT-PCR Test is intended for use in patients meeting clinical criteria or epidemiological criteria for Zika virus testing according to the US Centers for Disease Control and Prevention.
The test can only be used by laboratories certified under the Clinical Laboratory Improvement Amendments of 1988 (CLIA), 42 U.S.C. § 263a, to perform high complexity tests, or by similarly qualified non-US laboratories.
About the EUA
The LightMix® Zika rRT-PCR Test has not been FDA-cleared or approved. An EUA allows for the use of unapproved medical products or unapproved uses of approved medical products in an emergency.
The products must be used to diagnose, treat, or prevent serious or life-threatening conditions caused by chemical, biological, radiological, or nuclear threat agents, when there are no adequate alternatives.
This means the LightMix® Zika rRT-PCR Test is only authorized for use as long as circumstances exist to justify the authorization of the emergency use of
in vitro diagnostics for the detection of Zika virus under section 564(b)(1) of the Federal Food, Drug & Cosmetic Act, 21 U.S.C.§360bbb-3(b)(1), unless the authorization is terminated or revoked sooner.
About the test
The LightMix® Zika rRT-PCR Test is designed to provide qualitative detection of Zika viral RNA in combination with a full process RNA control that monitors all steps from extraction to PCR result.
Nucleic acid extraction is authorized to be performed with Roche’s MagNA Pure Compact Instrument (and Isolation Kit I – Large Volume) or, for laboratories wanting to process a higher number of samples, the MagNA Pure 96 Instrument (and DNA and Viral NA Large Volume Kit) for high-throughput automated extraction.
The test was developed to run on Roche’s LightCycler® 480 Instrument II or cobas z 480 Analyzer. The end-to-end automated process from sample preparation to results for up to 96 samples can be performed in 2.5 hours.
The LightMix® Zika rRT-PCR Test is manufactured by TIB MOLBIOL GmbH and distributed by Roche.
Photo by Graham Colm
The US Food and Drug Administration (FDA) has issued an emergency use authorization (EUA) for the LightMix® Zika rRT-PCR Test.
The test, distributed by Roche, is used to detect the Zika virus in EDTA plasma or serum samples.
The LightMix® Zika rRT-PCR Test is intended for use in patients meeting clinical criteria or epidemiological criteria for Zika virus testing according to the US Centers for Disease Control and Prevention.
The test can only be used by laboratories certified under the Clinical Laboratory Improvement Amendments of 1988 (CLIA), 42 U.S.C. § 263a, to perform high complexity tests, or by similarly qualified non-US laboratories.
About the EUA
The LightMix® Zika rRT-PCR Test has not been FDA-cleared or approved. An EUA allows for the use of unapproved medical products or unapproved uses of approved medical products in an emergency.
The products must be used to diagnose, treat, or prevent serious or life-threatening conditions caused by chemical, biological, radiological, or nuclear threat agents, when there are no adequate alternatives.
This means the LightMix® Zika rRT-PCR Test is only authorized for use as long as circumstances exist to justify the authorization of the emergency use of
in vitro diagnostics for the detection of Zika virus under section 564(b)(1) of the Federal Food, Drug & Cosmetic Act, 21 U.S.C.§360bbb-3(b)(1), unless the authorization is terminated or revoked sooner.
About the test
The LightMix® Zika rRT-PCR Test is designed to provide qualitative detection of Zika viral RNA in combination with a full process RNA control that monitors all steps from extraction to PCR result.
Nucleic acid extraction is authorized to be performed with Roche’s MagNA Pure Compact Instrument (and Isolation Kit I – Large Volume) or, for laboratories wanting to process a higher number of samples, the MagNA Pure 96 Instrument (and DNA and Viral NA Large Volume Kit) for high-throughput automated extraction.
The test was developed to run on Roche’s LightCycler® 480 Instrument II or cobas z 480 Analyzer. The end-to-end automated process from sample preparation to results for up to 96 samples can be performed in 2.5 hours.
The LightMix® Zika rRT-PCR Test is manufactured by TIB MOLBIOL GmbH and distributed by Roche.
Photo by Graham Colm
The US Food and Drug Administration (FDA) has issued an emergency use authorization (EUA) for the LightMix® Zika rRT-PCR Test.
The test, distributed by Roche, is used to detect the Zika virus in EDTA plasma or serum samples.
The LightMix® Zika rRT-PCR Test is intended for use in patients meeting clinical criteria or epidemiological criteria for Zika virus testing according to the US Centers for Disease Control and Prevention.
The test can only be used by laboratories certified under the Clinical Laboratory Improvement Amendments of 1988 (CLIA), 42 U.S.C. § 263a, to perform high complexity tests, or by similarly qualified non-US laboratories.
About the EUA
The LightMix® Zika rRT-PCR Test has not been FDA-cleared or approved. An EUA allows for the use of unapproved medical products or unapproved uses of approved medical products in an emergency.
The products must be used to diagnose, treat, or prevent serious or life-threatening conditions caused by chemical, biological, radiological, or nuclear threat agents, when there are no adequate alternatives.
This means the LightMix® Zika rRT-PCR Test is only authorized for use as long as circumstances exist to justify the authorization of the emergency use of
in vitro diagnostics for the detection of Zika virus under section 564(b)(1) of the Federal Food, Drug & Cosmetic Act, 21 U.S.C.§360bbb-3(b)(1), unless the authorization is terminated or revoked sooner.
About the test
The LightMix® Zika rRT-PCR Test is designed to provide qualitative detection of Zika viral RNA in combination with a full process RNA control that monitors all steps from extraction to PCR result.
Nucleic acid extraction is authorized to be performed with Roche’s MagNA Pure Compact Instrument (and Isolation Kit I – Large Volume) or, for laboratories wanting to process a higher number of samples, the MagNA Pure 96 Instrument (and DNA and Viral NA Large Volume Kit) for high-throughput automated extraction.
The test was developed to run on Roche’s LightCycler® 480 Instrument II or cobas z 480 Analyzer. The end-to-end automated process from sample preparation to results for up to 96 samples can be performed in 2.5 hours.
The LightMix® Zika rRT-PCR Test is manufactured by TIB MOLBIOL GmbH and distributed by Roche.
Ties to industry among NCCN guideline authors
A study published in JAMA Oncology has quantified financial ties to the pharmaceutical industry among authors of National Comprehensive Cancer Network (NCCN) guidelines.
In 2014, the authors studied received more money in research payments than “general” payments (for things like consulting, meals, and lodging)—$29 million vs $1.25 million.
But more of the authors received general payments than research payments—84% vs 47%.
Study investigators said this finding may mean that some of the guideline authors are receiving general payments unconnected to research. However, because the study only included 1 year of data, these results may not tell the full story.
“Understanding the extent to which guideline authors have financial relationships with the pharmaceutical industry—and the types of financial arrangements that they have—is useful for the NCCN and for the public,” said investigator Stacie Dusetzina, PhD, of the University of North Carolina at Chapel Hill.
“As we learn more about the role of industry payments in shaping prescribing and practice, it is best to proceed with caution and continue to encourage transparency.”
For this study, Dr Dusetzina and her colleagues analyzed financial conflicts of interest (FCOIs) for 125 panelists who worked on setting the NCCN guidelines for lung, breast, prostate, and colorectal cancer (the cancers with the highest incidence in the US).
Eighty-six percent (n=108) of the guideline authors reported at least 1 FCOI in 2014. The total value of FCOIs was $30,287,549, which included $29,036,127 in research payments and $1,251,422 in general payments.
Eighty-four percent of the authors (n=105) received general payments, and 47% (n=59) received research payments.
The authors received an average of $10,011 in general payments and an average of $236,066 in research payments.
The majority of the payments received were within the limits set by the NCCN, but 8 authors (6%) exceeded them. The NCCN says guideline authors cannot receive $20,000 or more from a single company or $50,000 or more in total.
Dr Dusetzina and her colleagues noted that this study was not designed to explore whether the payments influenced the guideline authors’ clinical practice or the recommendations they made in the guidelines.
However, finding a high prevalence of financial relationships with industry among guideline authors lays the foundation for future studies to investigate the impact of such relationships.
“It is not a given that industry funding leads to undue influence,” Dr Dusetzina said, “but it is important to analyze these relationships and the potential impact they have on care guidelines because they do influence patient care decisions and the cost of providing patient care.”
A study published in JAMA Oncology has quantified financial ties to the pharmaceutical industry among authors of National Comprehensive Cancer Network (NCCN) guidelines.
In 2014, the authors studied received more money in research payments than “general” payments (for things like consulting, meals, and lodging)—$29 million vs $1.25 million.
But more of the authors received general payments than research payments—84% vs 47%.
Study investigators said this finding may mean that some of the guideline authors are receiving general payments unconnected to research. However, because the study only included 1 year of data, these results may not tell the full story.
“Understanding the extent to which guideline authors have financial relationships with the pharmaceutical industry—and the types of financial arrangements that they have—is useful for the NCCN and for the public,” said investigator Stacie Dusetzina, PhD, of the University of North Carolina at Chapel Hill.
“As we learn more about the role of industry payments in shaping prescribing and practice, it is best to proceed with caution and continue to encourage transparency.”
For this study, Dr Dusetzina and her colleagues analyzed financial conflicts of interest (FCOIs) for 125 panelists who worked on setting the NCCN guidelines for lung, breast, prostate, and colorectal cancer (the cancers with the highest incidence in the US).
Eighty-six percent (n=108) of the guideline authors reported at least 1 FCOI in 2014. The total value of FCOIs was $30,287,549, which included $29,036,127 in research payments and $1,251,422 in general payments.
Eighty-four percent of the authors (n=105) received general payments, and 47% (n=59) received research payments.
The authors received an average of $10,011 in general payments and an average of $236,066 in research payments.
The majority of the payments received were within the limits set by the NCCN, but 8 authors (6%) exceeded them. The NCCN says guideline authors cannot receive $20,000 or more from a single company or $50,000 or more in total.
Dr Dusetzina and her colleagues noted that this study was not designed to explore whether the payments influenced the guideline authors’ clinical practice or the recommendations they made in the guidelines.
However, finding a high prevalence of financial relationships with industry among guideline authors lays the foundation for future studies to investigate the impact of such relationships.
“It is not a given that industry funding leads to undue influence,” Dr Dusetzina said, “but it is important to analyze these relationships and the potential impact they have on care guidelines because they do influence patient care decisions and the cost of providing patient care.”
A study published in JAMA Oncology has quantified financial ties to the pharmaceutical industry among authors of National Comprehensive Cancer Network (NCCN) guidelines.
In 2014, the authors studied received more money in research payments than “general” payments (for things like consulting, meals, and lodging)—$29 million vs $1.25 million.
But more of the authors received general payments than research payments—84% vs 47%.
Study investigators said this finding may mean that some of the guideline authors are receiving general payments unconnected to research. However, because the study only included 1 year of data, these results may not tell the full story.
“Understanding the extent to which guideline authors have financial relationships with the pharmaceutical industry—and the types of financial arrangements that they have—is useful for the NCCN and for the public,” said investigator Stacie Dusetzina, PhD, of the University of North Carolina at Chapel Hill.
“As we learn more about the role of industry payments in shaping prescribing and practice, it is best to proceed with caution and continue to encourage transparency.”
For this study, Dr Dusetzina and her colleagues analyzed financial conflicts of interest (FCOIs) for 125 panelists who worked on setting the NCCN guidelines for lung, breast, prostate, and colorectal cancer (the cancers with the highest incidence in the US).
Eighty-six percent (n=108) of the guideline authors reported at least 1 FCOI in 2014. The total value of FCOIs was $30,287,549, which included $29,036,127 in research payments and $1,251,422 in general payments.
Eighty-four percent of the authors (n=105) received general payments, and 47% (n=59) received research payments.
The authors received an average of $10,011 in general payments and an average of $236,066 in research payments.
The majority of the payments received were within the limits set by the NCCN, but 8 authors (6%) exceeded them. The NCCN says guideline authors cannot receive $20,000 or more from a single company or $50,000 or more in total.
Dr Dusetzina and her colleagues noted that this study was not designed to explore whether the payments influenced the guideline authors’ clinical practice or the recommendations they made in the guidelines.
However, finding a high prevalence of financial relationships with industry among guideline authors lays the foundation for future studies to investigate the impact of such relationships.
“It is not a given that industry funding leads to undue influence,” Dr Dusetzina said, “but it is important to analyze these relationships and the potential impact they have on care guidelines because they do influence patient care decisions and the cost of providing patient care.”
Reasons for high cost of prescription drugs in US
Photo courtesy of the CDC
High prescription drug prices in the US have a few causes, according to researchers.
They said causes include the approach the US has taken to granting government-protected monopolies to drug manufacturers, strategies that delay access to generic drugs, and the restriction of price negotiation at a level not observed in other industrialized nations.
The researchers outlined these issues in JAMA.
Aaron S. Kesselheim, MD, of Brigham and Women’s Hospital in Boston, Massachusetts, and his colleagues conducted this research.
The team reviewed the medical and health policy literature from January 2005 to July 2016, looking for articles addressing the sources of drug prices in the US, the justifications and consequences of high prices, and possible solutions.
The researchers found that per-capita prescription drug spending is higher in the US than in all other countries. In 2013, per-capita spending on prescription drugs was $858 in the US, compared with an average of $400 for 19 other industrialized nations.
Dr Kesselheim and his colleagues said prescription drug spending in the US is largely driven by brand-name drug prices that have been increasing in recent years. And drug prices are higher in the US because the US healthcare system allows manufacturers to set their own price for a given product.
In countries with national health insurance systems, on the other hand, a delegated body negotiates drug prices or rejects coverage of products if the price demanded by the manufacturer is excessive in light of the benefit provided. Manufacturers may then decide to offer the drug at a lower price.
The researchers said the most important factor that allows US manufacturers to set high drug prices is market exclusivity. And although cheaper generic drugs can be made available after an exclusivity period has passed, there are strategies for keeping these drugs off the market.
Furthermore, the negotiating power of the payer is constrained by several factors, including the requirement that most government drug payment plans cover nearly all products.
Considering these findings together, Dr Kesselheim and his colleagues said the most realistic short-term strategies to address high drug prices in the US include:
- Enforcing more stringent requirements for market exclusivity rights
- Ensuring timely generic drug availability
- Providing greater opportunities for price negotiation by governmental payers
- Generating more evidence about comparative cost-effectiveness of therapeutic alternatives
- Educating patients, prescribers, payers, and policy makers about these choices.
The researchers said there is little evidence that such policies would hamper innovation. In fact, they might even drive the development of more valuable new therapies rather than rewarding the persistence of older ones.
Photo courtesy of the CDC
High prescription drug prices in the US have a few causes, according to researchers.
They said causes include the approach the US has taken to granting government-protected monopolies to drug manufacturers, strategies that delay access to generic drugs, and the restriction of price negotiation at a level not observed in other industrialized nations.
The researchers outlined these issues in JAMA.
Aaron S. Kesselheim, MD, of Brigham and Women’s Hospital in Boston, Massachusetts, and his colleagues conducted this research.
The team reviewed the medical and health policy literature from January 2005 to July 2016, looking for articles addressing the sources of drug prices in the US, the justifications and consequences of high prices, and possible solutions.
The researchers found that per-capita prescription drug spending is higher in the US than in all other countries. In 2013, per-capita spending on prescription drugs was $858 in the US, compared with an average of $400 for 19 other industrialized nations.
Dr Kesselheim and his colleagues said prescription drug spending in the US is largely driven by brand-name drug prices that have been increasing in recent years. And drug prices are higher in the US because the US healthcare system allows manufacturers to set their own price for a given product.
In countries with national health insurance systems, on the other hand, a delegated body negotiates drug prices or rejects coverage of products if the price demanded by the manufacturer is excessive in light of the benefit provided. Manufacturers may then decide to offer the drug at a lower price.
The researchers said the most important factor that allows US manufacturers to set high drug prices is market exclusivity. And although cheaper generic drugs can be made available after an exclusivity period has passed, there are strategies for keeping these drugs off the market.
Furthermore, the negotiating power of the payer is constrained by several factors, including the requirement that most government drug payment plans cover nearly all products.
Considering these findings together, Dr Kesselheim and his colleagues said the most realistic short-term strategies to address high drug prices in the US include:
- Enforcing more stringent requirements for market exclusivity rights
- Ensuring timely generic drug availability
- Providing greater opportunities for price negotiation by governmental payers
- Generating more evidence about comparative cost-effectiveness of therapeutic alternatives
- Educating patients, prescribers, payers, and policy makers about these choices.
The researchers said there is little evidence that such policies would hamper innovation. In fact, they might even drive the development of more valuable new therapies rather than rewarding the persistence of older ones.
Photo courtesy of the CDC
High prescription drug prices in the US have a few causes, according to researchers.
They said causes include the approach the US has taken to granting government-protected monopolies to drug manufacturers, strategies that delay access to generic drugs, and the restriction of price negotiation at a level not observed in other industrialized nations.
The researchers outlined these issues in JAMA.
Aaron S. Kesselheim, MD, of Brigham and Women’s Hospital in Boston, Massachusetts, and his colleagues conducted this research.
The team reviewed the medical and health policy literature from January 2005 to July 2016, looking for articles addressing the sources of drug prices in the US, the justifications and consequences of high prices, and possible solutions.
The researchers found that per-capita prescription drug spending is higher in the US than in all other countries. In 2013, per-capita spending on prescription drugs was $858 in the US, compared with an average of $400 for 19 other industrialized nations.
Dr Kesselheim and his colleagues said prescription drug spending in the US is largely driven by brand-name drug prices that have been increasing in recent years. And drug prices are higher in the US because the US healthcare system allows manufacturers to set their own price for a given product.
In countries with national health insurance systems, on the other hand, a delegated body negotiates drug prices or rejects coverage of products if the price demanded by the manufacturer is excessive in light of the benefit provided. Manufacturers may then decide to offer the drug at a lower price.
The researchers said the most important factor that allows US manufacturers to set high drug prices is market exclusivity. And although cheaper generic drugs can be made available after an exclusivity period has passed, there are strategies for keeping these drugs off the market.
Furthermore, the negotiating power of the payer is constrained by several factors, including the requirement that most government drug payment plans cover nearly all products.
Considering these findings together, Dr Kesselheim and his colleagues said the most realistic short-term strategies to address high drug prices in the US include:
- Enforcing more stringent requirements for market exclusivity rights
- Ensuring timely generic drug availability
- Providing greater opportunities for price negotiation by governmental payers
- Generating more evidence about comparative cost-effectiveness of therapeutic alternatives
- Educating patients, prescribers, payers, and policy makers about these choices.
The researchers said there is little evidence that such policies would hamper innovation. In fact, they might even drive the development of more valuable new therapies rather than rewarding the persistence of older ones.
Team devises novel fluorescence microscopy technique
Researchers say they have developed a fluorescence microscopy technique that improves image resolution by acquiring 3 views of a sample at the same time.
The team applied their technique in 2 microscopy modes and used it to image several types of biological samples.
For both modes, the technique demonstrated a volumetric resolution of up to 235 by 235 by 340 nanometers, double the volumetric resolution of traditional methods.
The researchers believe this technique will prove particularly useful for watching the dynamics of biological processes, which can provide insights into the workings of healthy and diseased cells.
They described the technique in the journal Optica.
The researchers noted that most fluorescence microscopy methods fail to capture much of the fluorescence emitted from a sample, which represents lost information and reduces image resolution.
“In our work, we captured this previously neglected fluorescence and fused it with the traditional views used in conventional microscopy,” said study author Yicong Wu, PhD, of the National Institute of Biomedical Imaging and Bioengineering at the National Institutes of Health in Bethesda, Maryland.
“This increases resolution without compromising either temporal resolution or adding additional light to the sample.”
Adding a third objective lens
The new multi-view approach helps improve a technique the researchers previously developed called dual-view plane illumination microscopy (diSPIM). Scientists around the world employ commercial versions of diSPIM, which uses a thin sheet of light and 2 objective lenses to excite and detect fluorescence.
“The main motivation of this new research was that the resolution in diSPIM was limited by the numerical aperture of the upper lenses, and fluorescence emitted in the direction of the coverslip is not captured,” explained study author Hari Shroff, PhD, also of the National Institute of Biomedical Imaging and Bioengineering.
“We reasoned that if we could simultaneously image this neglected signal by adding a higher numerical aperture lens that acquired the bottom view, then we could boost the lateral resolution.”
In the improved diSPIM microscopy technique, each light sheet is tilted at a 45-degree angle relative to an additional lower objective lens.
In its current design, the researchers swept the lower objective’s plane of focus through the sample to image the previously unused fluorescence, but this mechanical scanning could be replaced with a passive optic in future versions of the microscope.
Using the multi-view approach improved the lateral, or horizontal, resolution of diSPIM to about 235 nm.
The researchers also implemented the new technique in wide-field mode by scanning the 3 objectives through a sample simultaneously to produce 3 individual 3D views. With this mode, the multi-view method improved axial, or Z-axis, resolution, to about 340 nm, an increase of 45%.
Merging 3 views into 1
Whether acquired in wide-field or light-sheet mode, the 3 views must be precisely aligned and also cleaned up with an image processing technique known as deconvolution.
“One helpful trick was to deconvolve each view first to increase image quality, contrast, and so forth, which then allowed accurate registration of the 3 views,” Dr Wu said. “In wide-field mode, we further aided registration of the images by adding fluorescent beads to the samples as point of reference.”
The researchers demonstrated the multi-view technique by imaging biological samples and were able to see detailed features not typically observable.
For example, the wide-field multi-view microscope clearly resolved the spherical protein shell present when Bacillus subtilis forms a spore and also allowed the researchers to observe the dynamics of organelles inside cells.
In light-sheet mode, the team clearly saw the 3D dynamic nature of tiny protrusions on living white blood cells when they acquired 150 triple-view images over 40 minutes.
Although other methods have been used to capture multiple views sequentially, the researchers said this new method improves spatial resolution without introducing additional illumination or compromising temporal resolution relative to conventional imaging.
This is important because additional light can be damaging and even deadly to living cells, and the temporal resolution is needed to capture fast processes.
The researchers are now exploring additional biological applications for the new system and are working to extend the method to other microscope modalities, such as confocal microscopy.
Researchers say they have developed a fluorescence microscopy technique that improves image resolution by acquiring 3 views of a sample at the same time.
The team applied their technique in 2 microscopy modes and used it to image several types of biological samples.
For both modes, the technique demonstrated a volumetric resolution of up to 235 by 235 by 340 nanometers, double the volumetric resolution of traditional methods.
The researchers believe this technique will prove particularly useful for watching the dynamics of biological processes, which can provide insights into the workings of healthy and diseased cells.
They described the technique in the journal Optica.
The researchers noted that most fluorescence microscopy methods fail to capture much of the fluorescence emitted from a sample, which represents lost information and reduces image resolution.
“In our work, we captured this previously neglected fluorescence and fused it with the traditional views used in conventional microscopy,” said study author Yicong Wu, PhD, of the National Institute of Biomedical Imaging and Bioengineering at the National Institutes of Health in Bethesda, Maryland.
“This increases resolution without compromising either temporal resolution or adding additional light to the sample.”
Adding a third objective lens
The new multi-view approach helps improve a technique the researchers previously developed called dual-view plane illumination microscopy (diSPIM). Scientists around the world employ commercial versions of diSPIM, which uses a thin sheet of light and 2 objective lenses to excite and detect fluorescence.
“The main motivation of this new research was that the resolution in diSPIM was limited by the numerical aperture of the upper lenses, and fluorescence emitted in the direction of the coverslip is not captured,” explained study author Hari Shroff, PhD, also of the National Institute of Biomedical Imaging and Bioengineering.
“We reasoned that if we could simultaneously image this neglected signal by adding a higher numerical aperture lens that acquired the bottom view, then we could boost the lateral resolution.”
In the improved diSPIM microscopy technique, each light sheet is tilted at a 45-degree angle relative to an additional lower objective lens.
In its current design, the researchers swept the lower objective’s plane of focus through the sample to image the previously unused fluorescence, but this mechanical scanning could be replaced with a passive optic in future versions of the microscope.
Using the multi-view approach improved the lateral, or horizontal, resolution of diSPIM to about 235 nm.
The researchers also implemented the new technique in wide-field mode by scanning the 3 objectives through a sample simultaneously to produce 3 individual 3D views. With this mode, the multi-view method improved axial, or Z-axis, resolution, to about 340 nm, an increase of 45%.
Merging 3 views into 1
Whether acquired in wide-field or light-sheet mode, the 3 views must be precisely aligned and also cleaned up with an image processing technique known as deconvolution.
“One helpful trick was to deconvolve each view first to increase image quality, contrast, and so forth, which then allowed accurate registration of the 3 views,” Dr Wu said. “In wide-field mode, we further aided registration of the images by adding fluorescent beads to the samples as point of reference.”
The researchers demonstrated the multi-view technique by imaging biological samples and were able to see detailed features not typically observable.
For example, the wide-field multi-view microscope clearly resolved the spherical protein shell present when Bacillus subtilis forms a spore and also allowed the researchers to observe the dynamics of organelles inside cells.
In light-sheet mode, the team clearly saw the 3D dynamic nature of tiny protrusions on living white blood cells when they acquired 150 triple-view images over 40 minutes.
Although other methods have been used to capture multiple views sequentially, the researchers said this new method improves spatial resolution without introducing additional illumination or compromising temporal resolution relative to conventional imaging.
This is important because additional light can be damaging and even deadly to living cells, and the temporal resolution is needed to capture fast processes.
The researchers are now exploring additional biological applications for the new system and are working to extend the method to other microscope modalities, such as confocal microscopy.
Researchers say they have developed a fluorescence microscopy technique that improves image resolution by acquiring 3 views of a sample at the same time.
The team applied their technique in 2 microscopy modes and used it to image several types of biological samples.
For both modes, the technique demonstrated a volumetric resolution of up to 235 by 235 by 340 nanometers, double the volumetric resolution of traditional methods.
The researchers believe this technique will prove particularly useful for watching the dynamics of biological processes, which can provide insights into the workings of healthy and diseased cells.
They described the technique in the journal Optica.
The researchers noted that most fluorescence microscopy methods fail to capture much of the fluorescence emitted from a sample, which represents lost information and reduces image resolution.
“In our work, we captured this previously neglected fluorescence and fused it with the traditional views used in conventional microscopy,” said study author Yicong Wu, PhD, of the National Institute of Biomedical Imaging and Bioengineering at the National Institutes of Health in Bethesda, Maryland.
“This increases resolution without compromising either temporal resolution or adding additional light to the sample.”
Adding a third objective lens
The new multi-view approach helps improve a technique the researchers previously developed called dual-view plane illumination microscopy (diSPIM). Scientists around the world employ commercial versions of diSPIM, which uses a thin sheet of light and 2 objective lenses to excite and detect fluorescence.
“The main motivation of this new research was that the resolution in diSPIM was limited by the numerical aperture of the upper lenses, and fluorescence emitted in the direction of the coverslip is not captured,” explained study author Hari Shroff, PhD, also of the National Institute of Biomedical Imaging and Bioengineering.
“We reasoned that if we could simultaneously image this neglected signal by adding a higher numerical aperture lens that acquired the bottom view, then we could boost the lateral resolution.”
In the improved diSPIM microscopy technique, each light sheet is tilted at a 45-degree angle relative to an additional lower objective lens.
In its current design, the researchers swept the lower objective’s plane of focus through the sample to image the previously unused fluorescence, but this mechanical scanning could be replaced with a passive optic in future versions of the microscope.
Using the multi-view approach improved the lateral, or horizontal, resolution of diSPIM to about 235 nm.
The researchers also implemented the new technique in wide-field mode by scanning the 3 objectives through a sample simultaneously to produce 3 individual 3D views. With this mode, the multi-view method improved axial, or Z-axis, resolution, to about 340 nm, an increase of 45%.
Merging 3 views into 1
Whether acquired in wide-field or light-sheet mode, the 3 views must be precisely aligned and also cleaned up with an image processing technique known as deconvolution.
“One helpful trick was to deconvolve each view first to increase image quality, contrast, and so forth, which then allowed accurate registration of the 3 views,” Dr Wu said. “In wide-field mode, we further aided registration of the images by adding fluorescent beads to the samples as point of reference.”
The researchers demonstrated the multi-view technique by imaging biological samples and were able to see detailed features not typically observable.
For example, the wide-field multi-view microscope clearly resolved the spherical protein shell present when Bacillus subtilis forms a spore and also allowed the researchers to observe the dynamics of organelles inside cells.
In light-sheet mode, the team clearly saw the 3D dynamic nature of tiny protrusions on living white blood cells when they acquired 150 triple-view images over 40 minutes.
Although other methods have been used to capture multiple views sequentially, the researchers said this new method improves spatial resolution without introducing additional illumination or compromising temporal resolution relative to conventional imaging.
This is important because additional light can be damaging and even deadly to living cells, and the temporal resolution is needed to capture fast processes.
The researchers are now exploring additional biological applications for the new system and are working to extend the method to other microscope modalities, such as confocal microscopy.
Immunotherapy might treat, prevent malaria
Image courtesy of Ute
Frevert and Margaret Shear
A synthetic version of the protein PD-L2 can treat malaria in mice and protect them from re-infection, according to researchers.
The team’s experiments indicated that PD-L2 determines the severity of malaria infection and is essential for CD4+ T-cell immunity against malaria.
When the researchers administered soluble multimeric PD-L2 to mice, the animals were cured of severe malaria and protected from re-infection months later.
Michelle Wykes, DPhil, of QIMR Berghofer Medical Research Institute in Herston, Queensland, Australia, and her colleagues reported these results in Immunity.
The researchers noted that Plasmodium parasites exploit the interaction between PD-1 and PD-L1 to prevent T cells from fighting malaria, but the role of PD-L2 has not been clear.
With this study, the team found that PD-L2 regulates the PD-1—PD-L1 interaction and might therefore be used to treat malaria.
“We found that, when humans and mice are infected with severe malaria, levels of PD-L2 decrease, and so the T cells aren’t being told to keep fighting the parasites,” Dr Wykes explained.
“We don’t know how malaria manages to block the production of PD-L2. But once we knew how important this protein was for fighting the disease, we developed a synthetic version of it in the laboratory.”
The researchers gave 3 doses of this synthetic PD-L2 to mice that had been infected with a lethal dose of malaria.
“All of these mice were cured of the malaria,” Dr Wykes said. “About 5 months later, we re-infected the same mice with malaria parasites, but, this time, we didn’t give them any more of the synthetic protein. All of the mice were completely protected and didn’t become infected.”
Dr Wykes said these findings could form the basis for new ways to treat malaria in the future.
“[I]f this approach is successful, it should treat all species of malaria parasite,” she noted. “This would be a completely new way of treating malaria—by stimulating a person’s own immune system to destroy the parasites.”
Image courtesy of Ute
Frevert and Margaret Shear
A synthetic version of the protein PD-L2 can treat malaria in mice and protect them from re-infection, according to researchers.
The team’s experiments indicated that PD-L2 determines the severity of malaria infection and is essential for CD4+ T-cell immunity against malaria.
When the researchers administered soluble multimeric PD-L2 to mice, the animals were cured of severe malaria and protected from re-infection months later.
Michelle Wykes, DPhil, of QIMR Berghofer Medical Research Institute in Herston, Queensland, Australia, and her colleagues reported these results in Immunity.
The researchers noted that Plasmodium parasites exploit the interaction between PD-1 and PD-L1 to prevent T cells from fighting malaria, but the role of PD-L2 has not been clear.
With this study, the team found that PD-L2 regulates the PD-1—PD-L1 interaction and might therefore be used to treat malaria.
“We found that, when humans and mice are infected with severe malaria, levels of PD-L2 decrease, and so the T cells aren’t being told to keep fighting the parasites,” Dr Wykes explained.
“We don’t know how malaria manages to block the production of PD-L2. But once we knew how important this protein was for fighting the disease, we developed a synthetic version of it in the laboratory.”
The researchers gave 3 doses of this synthetic PD-L2 to mice that had been infected with a lethal dose of malaria.
“All of these mice were cured of the malaria,” Dr Wykes said. “About 5 months later, we re-infected the same mice with malaria parasites, but, this time, we didn’t give them any more of the synthetic protein. All of the mice were completely protected and didn’t become infected.”
Dr Wykes said these findings could form the basis for new ways to treat malaria in the future.
“[I]f this approach is successful, it should treat all species of malaria parasite,” she noted. “This would be a completely new way of treating malaria—by stimulating a person’s own immune system to destroy the parasites.”
Image courtesy of Ute
Frevert and Margaret Shear
A synthetic version of the protein PD-L2 can treat malaria in mice and protect them from re-infection, according to researchers.
The team’s experiments indicated that PD-L2 determines the severity of malaria infection and is essential for CD4+ T-cell immunity against malaria.
When the researchers administered soluble multimeric PD-L2 to mice, the animals were cured of severe malaria and protected from re-infection months later.
Michelle Wykes, DPhil, of QIMR Berghofer Medical Research Institute in Herston, Queensland, Australia, and her colleagues reported these results in Immunity.
The researchers noted that Plasmodium parasites exploit the interaction between PD-1 and PD-L1 to prevent T cells from fighting malaria, but the role of PD-L2 has not been clear.
With this study, the team found that PD-L2 regulates the PD-1—PD-L1 interaction and might therefore be used to treat malaria.
“We found that, when humans and mice are infected with severe malaria, levels of PD-L2 decrease, and so the T cells aren’t being told to keep fighting the parasites,” Dr Wykes explained.
“We don’t know how malaria manages to block the production of PD-L2. But once we knew how important this protein was for fighting the disease, we developed a synthetic version of it in the laboratory.”
The researchers gave 3 doses of this synthetic PD-L2 to mice that had been infected with a lethal dose of malaria.
“All of these mice were cured of the malaria,” Dr Wykes said. “About 5 months later, we re-infected the same mice with malaria parasites, but, this time, we didn’t give them any more of the synthetic protein. All of the mice were completely protected and didn’t become infected.”
Dr Wykes said these findings could form the basis for new ways to treat malaria in the future.
“[I]f this approach is successful, it should treat all species of malaria parasite,” she noted. “This would be a completely new way of treating malaria—by stimulating a person’s own immune system to destroy the parasites.”
Assay can aid blood biomarker research
Photo by Graham Colm
A new assay can overcome a limitation in blood biomarker research, according to a study published in Scientific Reports.
Researchers noted that transcriptome sequencing of whole-blood RNA holds promise for the identification and tracking of biomarkers.
Unfortunately, the high globin mRNA (gmRNA) content of erythrocytes can be problematic, causing technical bias and leaving biologically relevant molecules undetectable.
With this in mind, the researchers developed an assay known as GlobinLock, which is designed to preserve RNA quality by reducing globin content.
“The globin reduction rate of GlobinLock is sufficient for any application,” said study author Kaarel Krjutškov, PhD, of Karolinska Institutet in Huddinge, Sweden.
“It reduces the globin prevalence from 63% . . . to 5%, which makes it an effective tool for biotechnology companies as an additive to their kits.”
GlobinLock consists of a pair of gmRNA-specific oligonucleotides that silence the majority of globin RNA molecules by highly specific binding.
The oligonucleotides are introduced to a purified RNA sample and, according to the researchers, are effective immediately after RNA denaturation.
“We show that globin locking is fully effective not only for human samples but also for widely used animal models, like mouse and rat, cow, dog, and even zebrafish,” said study author Juha Kere, MD, PhD, of Karolinska Institutet.
Photo by Graham Colm
A new assay can overcome a limitation in blood biomarker research, according to a study published in Scientific Reports.
Researchers noted that transcriptome sequencing of whole-blood RNA holds promise for the identification and tracking of biomarkers.
Unfortunately, the high globin mRNA (gmRNA) content of erythrocytes can be problematic, causing technical bias and leaving biologically relevant molecules undetectable.
With this in mind, the researchers developed an assay known as GlobinLock, which is designed to preserve RNA quality by reducing globin content.
“The globin reduction rate of GlobinLock is sufficient for any application,” said study author Kaarel Krjutškov, PhD, of Karolinska Institutet in Huddinge, Sweden.
“It reduces the globin prevalence from 63% . . . to 5%, which makes it an effective tool for biotechnology companies as an additive to their kits.”
GlobinLock consists of a pair of gmRNA-specific oligonucleotides that silence the majority of globin RNA molecules by highly specific binding.
The oligonucleotides are introduced to a purified RNA sample and, according to the researchers, are effective immediately after RNA denaturation.
“We show that globin locking is fully effective not only for human samples but also for widely used animal models, like mouse and rat, cow, dog, and even zebrafish,” said study author Juha Kere, MD, PhD, of Karolinska Institutet.
Photo by Graham Colm
A new assay can overcome a limitation in blood biomarker research, according to a study published in Scientific Reports.
Researchers noted that transcriptome sequencing of whole-blood RNA holds promise for the identification and tracking of biomarkers.
Unfortunately, the high globin mRNA (gmRNA) content of erythrocytes can be problematic, causing technical bias and leaving biologically relevant molecules undetectable.
With this in mind, the researchers developed an assay known as GlobinLock, which is designed to preserve RNA quality by reducing globin content.
“The globin reduction rate of GlobinLock is sufficient for any application,” said study author Kaarel Krjutškov, PhD, of Karolinska Institutet in Huddinge, Sweden.
“It reduces the globin prevalence from 63% . . . to 5%, which makes it an effective tool for biotechnology companies as an additive to their kits.”
GlobinLock consists of a pair of gmRNA-specific oligonucleotides that silence the majority of globin RNA molecules by highly specific binding.
The oligonucleotides are introduced to a purified RNA sample and, according to the researchers, are effective immediately after RNA denaturation.
“We show that globin locking is fully effective not only for human samples but also for widely used animal models, like mouse and rat, cow, dog, and even zebrafish,” said study author Juha Kere, MD, PhD, of Karolinska Institutet.
Zika prompts HHS to declare public health emergency for Puerto Rico
The United States Department of Health and Human Services (HHS) has declared a public health emergency for Puerto Rico due to the Zika virus outbreak.
The declaration allows the federal government to provide support to the government of Puerto Rico to address the outbreak.
“This administration is committed to meeting the Zika outbreak in Puerto Rico with the necessary urgency,” said HHS Secretary Sylvia M. Burwell.
“This emergency declaration allows us to provide additional support to the Puerto Rican government and reminds us of the importance of pregnant women, women of child-bearing age, and their partners taking additional steps to protect themselves and their families from Zika.”
Through the public health emergency declaration, the government of Puerto Rico can:
- Apply for funding to hire and train unemployed workers to assist in vector control and outreach and education efforts through the US Department of Labor’s National Dislocated Worker Grant program
- Request the temporary reassignment of local public health department or agency personnel who are funded through Public Health Service Act programs in Puerto Rico to assist in the Zika response.
“The declaration made by HHS, which grants access to certain funds, is another example of collaboration between the federal government and the government of Puerto Rico,” said Alejandro García Padilla, governor of the Commonwealth of Puerto Rico.
In April, the HHS awarded $5 million to Puerto Rico health centers to fight the spread of the Zika virus. In March, the HHS shipped blood products to the island in response to the Zika outbreak.
Earlier this month, the US Centers for Disease Control and Prevention (CDC) awarded $16 million to US states and territories, including Puerto Rico, to fight the Zika virus. In July, the CDC awarded $25 million to US states, cities, and territories for the same purpose.
According to the Puerto Rico Department of Health, as of August 12, there have been 10,690 laboratory-confirmed cases of Zika in Puerto Rico, which includes 1035 pregnant women.
The actual number of people infected with Zika may be higher because most people with Zika infections have no symptoms and might not seek testing.
The United States Department of Health and Human Services (HHS) has declared a public health emergency for Puerto Rico due to the Zika virus outbreak.
The declaration allows the federal government to provide support to the government of Puerto Rico to address the outbreak.
“This administration is committed to meeting the Zika outbreak in Puerto Rico with the necessary urgency,” said HHS Secretary Sylvia M. Burwell.
“This emergency declaration allows us to provide additional support to the Puerto Rican government and reminds us of the importance of pregnant women, women of child-bearing age, and their partners taking additional steps to protect themselves and their families from Zika.”
Through the public health emergency declaration, the government of Puerto Rico can:
- Apply for funding to hire and train unemployed workers to assist in vector control and outreach and education efforts through the US Department of Labor’s National Dislocated Worker Grant program
- Request the temporary reassignment of local public health department or agency personnel who are funded through Public Health Service Act programs in Puerto Rico to assist in the Zika response.
“The declaration made by HHS, which grants access to certain funds, is another example of collaboration between the federal government and the government of Puerto Rico,” said Alejandro García Padilla, governor of the Commonwealth of Puerto Rico.
In April, the HHS awarded $5 million to Puerto Rico health centers to fight the spread of the Zika virus. In March, the HHS shipped blood products to the island in response to the Zika outbreak.
Earlier this month, the US Centers for Disease Control and Prevention (CDC) awarded $16 million to US states and territories, including Puerto Rico, to fight the Zika virus. In July, the CDC awarded $25 million to US states, cities, and territories for the same purpose.
According to the Puerto Rico Department of Health, as of August 12, there have been 10,690 laboratory-confirmed cases of Zika in Puerto Rico, which includes 1035 pregnant women.
The actual number of people infected with Zika may be higher because most people with Zika infections have no symptoms and might not seek testing.
The United States Department of Health and Human Services (HHS) has declared a public health emergency for Puerto Rico due to the Zika virus outbreak.
The declaration allows the federal government to provide support to the government of Puerto Rico to address the outbreak.
“This administration is committed to meeting the Zika outbreak in Puerto Rico with the necessary urgency,” said HHS Secretary Sylvia M. Burwell.
“This emergency declaration allows us to provide additional support to the Puerto Rican government and reminds us of the importance of pregnant women, women of child-bearing age, and their partners taking additional steps to protect themselves and their families from Zika.”
Through the public health emergency declaration, the government of Puerto Rico can:
- Apply for funding to hire and train unemployed workers to assist in vector control and outreach and education efforts through the US Department of Labor’s National Dislocated Worker Grant program
- Request the temporary reassignment of local public health department or agency personnel who are funded through Public Health Service Act programs in Puerto Rico to assist in the Zika response.
“The declaration made by HHS, which grants access to certain funds, is another example of collaboration between the federal government and the government of Puerto Rico,” said Alejandro García Padilla, governor of the Commonwealth of Puerto Rico.
In April, the HHS awarded $5 million to Puerto Rico health centers to fight the spread of the Zika virus. In March, the HHS shipped blood products to the island in response to the Zika outbreak.
Earlier this month, the US Centers for Disease Control and Prevention (CDC) awarded $16 million to US states and territories, including Puerto Rico, to fight the Zika virus. In July, the CDC awarded $25 million to US states, cities, and territories for the same purpose.
According to the Puerto Rico Department of Health, as of August 12, there have been 10,690 laboratory-confirmed cases of Zika in Puerto Rico, which includes 1035 pregnant women.
The actual number of people infected with Zika may be higher because most people with Zika infections have no symptoms and might not seek testing.