US researchers at Johns Hopkins, Florida State and Emory universities found that Zika infects and destroys the cells that form the cerebral cortex.
After exposure to the virus, 90% of cortical neuronal cells were infected, says the study.
What are the chances that a naturally occurring virus evolves and mutates to develop an ability to specifically attack and destroy brain cells that directly influence fetal development? Yes, I also thought so.
The Zika virus, which has been found to be a genetically modified version of a disease transmitted by the mosquito Aedes-aegypti, has now been found to directly target cerebral fetal cells that, researchers say, are responsible for a child’s developments in the womb.
The conclusion that Zika is made to directly attack brain cells comes from an investigation conducted by a group of researchers from John Hopkins, Florida State and Emory universities.
Their findings allegedly help clarify the association between the virus and microcephaly. The study, its authors say, is not conclusive proof that Zika causes severe fetal malformation, only that the virus does kill cerebral cells that are directly involved in fetal development. The direct relation between the virus and severe malformations may be confirmed at a later time.
The increase in cases of microcephaly possibly linked to the virus prompted the World Health Organization (WHO) to declare a global health alert in the same fashion that the organization did with the H1N1 and the Ebola pandemic.
For the study, published Friday in the journal Cell Stem Cell, the researchers used three types of cultured cells in the laboratory and found that Zika selectively affects essential stem cells that intervene in the formation of the cerebral cortex of a fetus.
The study says that the virus reduces a cell’s ability to divide, produce new neurons and also makes them more likely to die. This causes the cerebral cortex not to form properly or not to regenerate.
Infection also occurs very rapidly: the researchers found that three days after exposure to the virus, 90% of cortical neuronal cells were infected.
“These findings may be related to the alteration of brain development, but it is more likely that direct evidence of the link between Zika and microcephaly appears in clinical trials,” the authors clarify.
“We are trying to fill the knowledge gap between infection and neurological defects. This study is a very first step, but it answers a key question.
The study, researchers say, “allows us to focus our research. We can now study the virus, test drugs and study the biology of the correct type of cell,” says in a note Hengli Tang, one of the lead authors and a professor of biological science at Florida State University.