Interaction of complement with Neisseria meningitidis and Neisseria gonorrhoeae

Abstract

The importance of the complement system in host defense against systemic infection caused by neisseriae is emphasized by a number of clinical observations documenting the importance of antibody-dependent, complement-mediated serum bactericidal activity in protection from systemic meningococcal disease (17) and the well-recognized association between the resistance of gonococci to complement-dependent serum bactericidal activity and the development of disseminated gonococcal infection (46, 49). Moreover, individuals with inherited complement deficiencies have a markedly increased risk (ca. 6,000-fold) of acquiring systemic neisserial infections and are subject to recurrent episodes of systemic meningococcal and gonococcal infections (37, 43). The purpose of this report is to review the complement cascade with particular reference to its importance in host defense against bacterial diseases, to compare and contrast neisserial disease in complement-deficient and complementsufficient individuals, to examine the molecular and functional basis for the particular importance of complement in host defense against these infections, and to examine the immunologic basis for prevention of neisserial disease in complement-deficient individuals.