Seminar: Nicole Baumgarth

B cells control and are controlled by infection-induced innate immune signals

B cell responses to infections are multi-functional and complex and provide effective immune defense through mechanisms that go well beyond the production of neutralizing antibodies from germinal center responses. Their responses are also critically shaped by the nature of the pathogen, which in some cases, such as during persistent infection with Borrelia burgdorferi, the bacteria causing Lyme disease in humans, subverts effective humoral immunity, as well as by the complex innate immune signals mounted in response to the infection. The presentation will outline some critical B cell functions that regulate immediate early inflammatory responses to Influenza virus infection through the elaboration of the neurotransmitter and immunomodulator acetylcholine, and the early generation of secreted IgM. It will further describe how successful early B cell responses to Influenza virus infection are in turn dependent on innate signals that integrate with antigen-specific BCR-mediated signals and signals from the early-secreted IgM to support induction of protective T-dependent B cell responses and long-lived immunity.