Covering Pandemic and Seasonal Flu, H5N1 `Bird Flu, Emerging Infectious Diseases, public health, community & Individual preparedness, and anything else that piques my admittedly eclectic interests
Friday, March 04, 2016
Cell Stem Cell: Zika Virus Infects Human Cortical Neural Progenitors
#11,098
Although we've a compelling spatial-temporal link between Zika virus outbreaks and increases in microcephaly in Brazil (and to a lesser extent in French Polynesia), we still lack proof of causation.
One of the many barriers to proving causation is finding a plausible mechanism by which the Zika virus could produce the kind of profound fetal brain anomalies that have been reported.
Today, in a brief report published in the journal Cell Stem Cell, researchers working with lab-grown human stem cells have shown the Zika virus selectively infects the type of cells that form the brain’s cortex, and importantly, infection `increases cell death and dysregulates cell-cycle progression,
resulting in attenuated hNPC growth.'
The full report can be accessed at the link below. Below that you'll find a link and some excerpts from a press release.
•ZIKV-infected hNPCs produce infectious ZIKV particles
•ZIKV infection leads to increased cell death of hNPCs
•ZIKV infection dysregulates cell cycle and transcription in hNPCs
Summary
The
suspected link between infection by Zika virus (ZIKV), a re-emerging
flavivirus, and microcephaly is an urgent global health concern. The
direct target cells of ZIKV in the developing human fetus are not clear.
Here we show that a strain of the ZIKV, MR766, serially passaged in
monkey and mosquito cells efficiently infects human neural progenitor
cells (hNPCs) derived from induced pluripotent stem cells.
Infected
hNPCs further release infectious ZIKV particles. Importantly, ZIKV
infection increases cell death and dysregulates cell-cycle progression,
resulting in attenuated hNPC growth. Global gene expression analysis of
infected hNPCs reveals transcriptional dysregulation, notably of
cell-cycle-related pathways. Our results identify hNPCs as a direct ZIKV
target.
In addition, we establish a tractable experimental model system
to investigate the impact and mechanism of ZIKV on human brain
development and provide a platform to screen therapeutic compounds.
The Zika virus infects a type of neural stem cell that gives rise to
the brain's cerebral cortex, Johns Hopkins and Florida State researchers
report March 4 in Cell Stem Cell. On laboratory dishes, these
stem cells were found to be havens for viral reproduction, resulting in
cell death and/or disruption of cell growth.
While this study does not
prove the direct link between Zika and microcephaly, it does pinpoint
where the virus may be doing the most damage.
The researchers, led by Guo-li Ming and Hongjun Song of the Johns
Hopkins University School of Medicine and Hengli Tang of Florida State
University, with collaborators at the Emory University School of
Medicine, worked around the clock for a month to conduct the study,
which provides a new platform to learn about the Zika virus using
neuronal cells derived from human induced pluripotent stem cells. In the
near future, the researchers hope to grow mini-brains from the stem
cells to observe the long-term effects of Zika infection on neural
tissue and to screen for potential therapeutics.
