Enzyme-linked immunosorbent assay for measurement of IgM and IgG antibodies to group A,B, C and G streptococci and changes of antibody levels.

Abstract

Abstract:Beta-hemolytic streptococci were isolated by throat-swab once a month from　January,1984 through December,1988. The subjects were school aged children　accommodated in an institution because of weak physical condition or chronic diseases、Serum immunoglobulin M(lgM)and immunoglobulin G(lgG)antibodies were measured　by an enzyme-linked immunosorbent assay(ELISA), using group A streptococci(type T-4,T-6 and T-12), group B streptococci (type Ia, Ib, Ic, Ⅱ and Ⅲ), group C strept-ococci and group G streptococcal antigens. The results are ummarized as follows:

Group G streptococci were isolated more frequently than the other groups of beta-hemolytic streptococci in 1987 and 1988.Changes in the groups and types of beta-hemolytic streptococci, during this period, were found in 1530f 293 cases. Group and type-specific

IgM and IgG antibodies were confirmed in the sera from beta-hemolytic streptococci isolated children by ELISA. The children who had beta-hemolytic streptococci, of the same group or type, showed high levels of IgM and IgG antibodies, and those who had different groups and types also showed high levels immediately after isolation. These findings demonstrate the usefulness of ELISA as a serologic diagnosis of beta-hemolytic streptococcal infection.