Maternal host responses to poly(I:C) during pregnancy leads to both dysfunctional immune profiles and altered behaviour in the offspring

Problem Autism spectrum disorder (ASD)‐like phenotypes in murine models are linked to elevated pro‐inflammatory cytokine profiles caused by maternal immune activation (MIA), but whether MIA alters the immune response in the offspring remains unclear. Method of study Polyinosinic:polycytidylic acid (poly:[IC]) was used to induce MIA in immunocompetent and control TLR3‐deficient pregnant mice, and cytokine levels were measured in maternal and foetal organs. Furthermore, cytokines and behaviour responses were tested after challenge with lipopolysaccharide in 7‐day‐old and adult mice. Results MIA induced on E12 resulted in changes in the cytokine expression profile in maternal and foetal organs and correlated with TNFα and IL‐18 dysregulation in immune organs and brains from neonatal mice born to MIA‐induced dams. Such changes further correlated with altered behavioural responses in adulthood. Conclusion MIA induced by pathogens during pregnancy can interfere with the development of the foetal immune and nervous systems leading to dysfunctional immune responses and behaviour in offspring.