Assignment of weight-based antibody units to a human antipneumococcal standard reference serum, lot 89-S.

A human reference serum pool, lot 89-S, has been developed for use in quantitating concentrations of antibody to Streptococcus pneumoniae. Weight-based units have been assigned to antibodies to 11 pneumococcal polysaccharide (PnPs) serotypes (1, 3, 4, 5, 6B, 7F, 9V, 14, 18C, 19F, and 23F) by using enzyme-linked immunosorbent assay methodology and a human standard reference serum, USNRP IS 1644. The experimentally derived assignments for anti-PnPs antibodies of the immunoglobulin G (IgG), IgM, and IgA isotypes in lot 89-S correlate well to the separately determined immunoglobulin assignment.