Fetuses aren't as defenseless as they seem; they may be armed to fight off viruses long before birth.
It was thought that fetal immune cells were too immature to be useful and that fetuses and newborns relied on antibodies provided by their mothers.
Now David Vermijlen at the Institute for Medical Immunology in Brussels, Belgium, and his colleagues have shown that fetuses just 21 weeks old may be capable of fending off infections using their own immune cells.
This could lead to new vaccines for newborns and unborn babies.
- New Scientist magazine