Zika Virus Infects Human Neural Stem Cells

World

Philippine health officials have advised pregnant women to consider deferring nonessential travel to Zika-hit countries and worked to raise public awareness on how to fight infections, including by using insect repellents and wearing protective clothing.

“There are case reports for the Zika virus where they show that certain brain areas appear to have developed normally, but it is mostly the cortical structures that are missing”, said Guo-li Ming from Johns Hopkins’ Institute for Cell Engineering. However, these findings do not show definitive proof about the connection between Zika virus and microcephaly. However, they warned that the study does not prove a direct link between Zika and microcephaly in newborns.
A separate case study reported last week in the journal PLOS Neglected Tropical Diseases described a stillborn baby from a Brazilian mother infected with Zika in which the skull was filled with fluid but had no brain. Working with lab-grown human stem cells, scientists found that the virus selectively infected cells forming the brain’s cortex, the thin outer layer of folded gray matter.
That caused researchers to scramble and find a link between the virus and microcephaly in babies-a neurological condition that causes abnormally small heads and developmental delays.
“Unfortunately, we still have many unanswered questions”, said Dr. Christopher M. Zahn of the American College of Obstetricians and Gynecologists.
Moreover, there is no vaccine available against the virus and there is no medicine to cure the illness.
The virus was able to infect up to 90% of neural progenitor cells in a sample leading to almost a third of cells dying and the growth of the rest being disrupted.
The researchers, led by Chinese-born Guoli Ming and Hongjun Song of the Johns Hopkins University and Hengli Tang of Florida State University, with Peng Jin at the Emory University, worked around the clock for a month to conduct the study, after the World Health Organization declared microcephaly a public health emergency of global concern in early February. How is the virus entering the nervous system of the developing fetus? Laboratory tests found that the virus targeted key cells involved in brain development and then destroyed or disabled them, they said.
The information was based on two studies published Friday – one from the USA may have identified how the virus causes microcephaly. Some of the cells died after being infected.