Fc Receptors in Antimicrobial Protection.

Antibodies are the key effector molecules of the humoral immune system providing long-term protective immunity against a wide range of pathogens and regulating immune responses. Traditionally, antibody-mediated protection against microbes was thought to be mainly a result of neutralizing Fab–antigen interaction; however, an increasing number of studies show the importance of proper FcR engagement for the protective capacity of antimicrobial antibodies. In this chapter, we review FcR-mediated effector functions contributing to antimicrobial protection in a direct and indirect manner. Furthermore, we highlight recent findings about the important role of Fc–FcR interactions for antimicrobial protection in vivo and provide examples demonstrating the crucial role of proper FcR engagement for antibody-mediated protection against viruses, bacteria, fungi, and parasites.