Israeli researchers have found that a viral infection in a pregnant woman’s body can harm the fetal brain cells, even if the fetus is not infected with the virus, Weizmann Institute of Science (WIS) said Thursday.
This may be caused by the mother’s immune system response to a virus, affecting the fetal brain cells, according to a WIS research, published in the journal Molecular Psychiatry.
The team found in mice experiments that RNA viruses, that induce diseases such as flu, measles, Ebola and COVID-19, adversely affected fetuses, after their mothers were infected.
Thus, the fetuses’ microglia, which are immune cells in the brain, were affected and showed abnormal behavior.
It was also found that this adverse effect on the brain cells was not caused by the virus-mimicking molecules used in the experiments, but by the mothers’ immune response to the viral infection.
This response is carried out by the antiviral immune system’s protein interferon-beta, whose levels rise sharply as a result of virus infection.
Large amounts of this protein, which serves as the first line of defense against viral infection in mammals, can harm the brain cells.
The results showed that even when the fetus is not directly exposed to a virus in the mother’s body, the fetal brain cells might be damaged by the interferon-beta protein that the mother secretes in large amounts in response to the viral infection.
“Further research may find ways of protecting the fetus from the mother’s response to the virus, that is, from the interferon that rises during viral infection”, the researchers said.
“In the meantime, pregnant women would do well to exercise caution, so as to avoid becoming infected with viruses during pregnancy,” they concluded.