Immune Response of Infants and Children to Disseminated Infections with Neisseria meningitidis

Abstract

Acute- and convalescent-phase sera from 34 children and 10 young adults were studied to determine if, at what age, and to which antigens of <it>Neisseria meningitidis</it> they respond during disseminated disease. Seven children older than two years of age who were infected with group C or Y strains developed significant increases in both binding and bactericidal antibody. Children infected with group B strains infrequently (eight [31%] of 26) had measurable increases in serum antibody to this capsular polysaccharide; response was meager when it did occur, was unrelated to age, and was considerably poorer than that of young adults, of whom 80% responded. Convalescent-phase sera from all children contained bactericidal antibody. Binding capacity for group B polysaccharide accounted for only 35% of the bactericidal activity in convalescent-phase sera of children infected with group B strains. Bactericidal antibody in the sera of children who did not respond to capsular polysaccharides was often to a lipooligosac-charide antigen.