Streptococcal Group A polysaccharide Antibodies Assayed by an ELISA Determination of Antibodies in Rabbit Hyperimmune Sera; Normal levels in Man and Comparison with Levels in Patients with Rheumatic Fever and with Poststreptococcal Glomerulonephritis

An enzyme-linked immunosorbent assay (ELISA) was adapted to measure antibodies to streptococcal group A polysaccharide. The components of the reaction were studied, including the concentration of the polysaccharide antigen, the suppression of non-specific reactions, optimal conjugate binding conditions and the most suitable plates. The specificity of this test was documented by studies using immune sera and polysaccharide antigens of various groups of beta-hemolytic streptococci. In addition dynamics of the antibody response in animals as well as in man were investigated. The upper limit of normal level of this antibody in normal healthy persons was determined by this technique. We found that 80% of patients with rheumatic fever and acute glomerulonephritis showed an elevation of the group A polysaccharide antibody titer. Determination of this antibody response by the ELISA technique is clinically useful in evaluation patients with the nonsuppurative sequelae of group A streptococcal infections. © 1986, Gustav Fischer Verlag, Stuttgart · New York. All rights reserved.