Kappa and lambda light chain composition of antibody to the capsular polysaccharide of Haemophilus influenzae type b

Concentrations of total immunoglobulins bearing kappa and lambda light chains were measured in the sera of 215 healthy white children aged 6 months to 10 years. Both kappa and lambda concentrations increased with age. However, the concentration of immunoglobulins bearing kappa light chains increased at a greater rate than those bearing lambda light chains (P = .01). Thus, the kappa:lambda ratio of the youngest children (6-24 months) was significantly lower than that of the oldest (25-130 months) (P = .0015). The relationship between the IgG antibody concentration and the light chain composition of the specific antibody directed to Haemophilus influenzae type b (Hib) polysaccharide was also assessed in 62 of 215 serum samples with detectable Hib antibody. The IgG Hib antibody concentration was strongly correlated with the kappa:lambda Hib antibody ratio (r = .60, P = .001), and this correlation was independent of age. Thus, light chain selection and response to polysaccharides may be regulated by common mechanisms that mature late in ontogeny.