New antibody cuts mother-to-fetus Zika transmission in mice

An NIAID-funded team has discovered a Zika antibody that reduces mother-to-fetus transmission of the virus in pregnant mice. This research could lead to the development of vaccines or other therapeutics against the virus.

Researchers from Vanderbilt University, Washington University in St. Louis and Philadelphia-based Integral Molecular isolated antibody-secreting white blood cells of three people who had previously had a Zika infection. They generated antibodies from these cells and found that one, dubbed ZIKV-117, neutralized every Zika virus strain they tested, the NIAID said in a statement.

All male mice that were given the antibody--even those who received it 5 days after being infected--were more likely to survive Zika infection compared to mice given a control antibody, according to the statement. This result suggests that ZIKV-117 could be used to treat active Zika infection.

Meanwhile, pregnant mice that received ZIKV-117 before being infected with Zika had lower numbers of Zika virus in their blood and brain tissues than mice that were not treated with the antibody. Additionally, the team found “protective levels” of the antibody in fetal tissues and significantly slashed Zika levels in the placenta and fetal brain, according to the statement. The implications for humans are twofold: not only could the antibody tamp down mother-to-fetus virus transmission, but it could also combat any virus that makes it to the fetus.

More work is required before moving the antibody into human trials, but the findings could lead to new therapeutics and/or vaccines that could stop Zika in its tracks. The results are encouraging in the fight against an infection that typically causes mild symptoms, but is now known to cause microcephaly in babies born to women who contract the virus while pregnant.