Dialogue of the Microbiota with the Host Immune System: Implications for Inflammatory Disease and Autism

Our immune system is heavily influenced by commensal microbiota — the microbes that reside within us. In the intestine, specific microbes induce pro- or anti-inflammatory white blood cells called lymphocytes that maintain a healthy homeostasis.  An imbalance in microbiota can result in dysregulated T cells that contribute to autoimmunity and, potentially, to autism.

In this lecture, Dan Littman will describe how intestinal commensal bacteria shape functions of immune system cells that prevent invasion by pathogenic microbes but can also contribute to systemic inflammation. Th17 cells, which participate in multiple autoimmune diseases, are regulated by the microbiota. These cells also have a key pathogenic role in the maternal immune activation (MIA) model of autism, which posits that the prenatal environment and activation of the maternal immune system may contribute to autism. Activation of the pregnant mother’s innate immune response may result in lifelong behavioral defects in the offspring. Littman will discuss implications for preventing or treating autism.

If this lecture is videotaped, it will be posted here after production.