Immune modulation by schistosomes: mechanisms of regulatory B cell induction and inhibition of allergic asthma

Abstract

Parasitic

helminths modulate host immune responses. While the induction of type 2 immune

responses is a widely recognized feature of helminth infections, a network of

regulatory immune responses is often dominant during the chronic phase of infection. Suppression of the host immune system during helminth infections inhibits anti-parasite immunity, prevents tissue damage due to excessive inflammation and conveys spill-over suppression to inflammatory conditions such as allergy and asthma. The first part of this thesis focuses on the role of regulatory B cells, a prominent member of the immune regulatory network, in protection from allergic asthma by chronic Schistosoma (S.) mansoni infections. It furthermore identifies signals required for schistosome-induced regulatory B cell development. The second part of this thesis describes the protective effect of S. mansoni eggs, and a specific egg-derived glycoprotein, against allergic asthma in the absence of chronic infection. A better understanding how helminthes including S. mansoni modulate host immune responses, and the implications this has for inflammatory diseases such as allergic asthma, may provide valuable leads for the development of novel pharmaceutical agents for the treatment of allergic disorders.