Serogroup B and C Serum Bactericidal Assays

Meningococci are usually classified based on serological reactivity of their polysaccharide capsules with serogroups A, B, and C, currently the most common causes of disease. Serogroup A meningococci can cause massive outbreaks particularly in areas such as the African meningitis belt, whereas other areas such as in the Americas and Europe, serogroups B and C predominate. Although licensed vaccines for serogroups A and C exist, based on the polysaccharide capsules, no such vaccine exists thus far for serogroup B owing to its poor immunogenicity in humans. This chapter discusses and details serum bactericidal assay protocols for measuring the complement-mediated lysis of serogroups B and C meningococci by human sera following vaccination or disease.