ANALYSIS OF PROTECTIVE AND NONPROTECTIVE MONOCLONAL-ANTIBODIES SPECIFIC FOR BORDETELLA-PERTUSSIS LIPOOLIGOSACCHARIDE

In this study, it has been determined that immunoglobulin G1 (IgG1) an d IgG3 monoclonal antibodies directed to the lipooligosaccharide A of Bordetella pertussis were able to protect mice from fatal aerosol infe ction. No correlation was found between the bactericidal activity in v itro in the presence of complement and the protection in mice, since a bactericidal IgG3 did not elicit protection. In addition, no signific ant difference in protective capacity was observed with bactericidal a nd nonbactericidal IgG1 antibodies, indicating that bactericidal activ ity is not a requirement for protection mediated by certain anti-lipoo ligosaccharide A antibodies. A reduction in protection in C5-deficient mice was observed, suggesting a significant role for complement in ce rtain host defense mechanisms against B. pertussis infection.