Activation of the Maternal Immune System as a Risk Factor for Neuropsychiatric Disorders.

Maternal infection can alter the intrauterine environment, placing the developing fetus at risk. Serious infections of the mother or the fetus can cause severe problems or even miscarriage. The more common and seemingly benign infections, such as influenza, do not appear associated with such severe outcomes. However, recent work has shown that maternal inflammation associated with any infection has the potential to alter the fetal brain development. Epidemiological studies have demonstrated a strong association between maternal infection and subsequent development of neuropsychiatric illness in the offspring. Mouse models of maternal infection have shown long-lasting changes in the brain of offspring following maternal immune activation (MIA), as well as behavioral abnormalities related to human neuropsychiatric illness. Recent work has begun to elucidate the mechanisms through which the activated maternal immune system alters fetal brain development. We review the evidence from human and rodent studies showing that maternal infection is a risk factor for neuropsychiatric illness, and describe initial steps in a molecular mechanism mediating the effects of maternal immune activation on fetal brain development. [ABSTRACT FROM AUTHOR]