Bacterial Modulation of Fc Effector Functions

Immunoglobulins (Igs, antibodies) are key players in adaptive immunity, and pathways mediated through the effector Fc portion of Ig are instrumental in controlling bacterial infections. Therefore, it is not very surprising that bacterial pathogens and commensals through co-evolution with their hosts have learned many tricks to interfere with Fc effector functions. In this chapter, we describe three principally different bacterial strategies to interfere with immunoglobulins: Specific Ig binding, specific or unspecific Ig protelolysis, and, finally, specific and unspecific hydrolysis of functionally important carbohydrates on the immunoglobulins. Elucidating these bacterial immune evasion mechanism evidences bacteria-host co-evolution and provides insight into fundamental aspects of human adaptive immunity and pathogenesis of infection.