Comparison of IgG IgGl lgG2 immune responses to pneumococcal polysaccharide in atopic nonatopic children

Abstract

The levels of naturally occurring IgG, IgGl and lgG2 antibodies against polyvalent pneumococcal capsular polysaccharide antigen (Pneumovax®) were compared between atopic and nonatopic children with different ages, 6–12 months and 1, 2, 3, 4, 5–9 and 10–15 years, by enzyme-linked immunosorbent assay. Children with asthma, atopic dermatitis, food allergy or a combination of these, and those having serum IgE levels exceeding 50 IU/mL at 6–12 months old and 100 IU/mL at more than 1-year-old were included as atopic groups. Asymptomatic children whose serum IgE levels were less than these atopic standards and those not having detectable IgE antibodies to Dermatophagoides farinae comprised the nonatopic groups. Geometric mean levels of IgG and IgG 1 antibodies against pneumococcal antigen increased steadily with age, and that of IgG2 antibodies was low until 3 years of age and then gradually increased age-dependently up to 15 years of age. The levels of IgG antibody as well as IgG 1 and IgG 2 antibodies were not significantly different between atopic and nonatopic children in any age group. This suggests that the immune response to the most common bacterial pathogen in the respiratory tract does not influence atopic status.