[Isolation of high affinity antibodies to streptococcal group A polysaccharide reacting with thymus and cutaneous epithelial cells].

Anti-streptococcal A polysaccharide (anti-A polysaccharide) antibodies were isolated from sera of rabbits immunized with group A streptococci by means of immunosorbents. The antibodies were studied by indirect immunofluorescence method on sections of skin and thymus tissues. Most preparations of high affinity antibodies reacting with A polysaccharide in the immunodiffusion test also react with skin and thymus epithelial cells. No preparations of low affinity anti-A polysaccharide antibodies reacted with thymus or skin epithelium. It was found that the reaction of antibodies to A-polysaccharide with epithelial cells does not depend on the availability of antibodies cross reacting with group L streptococcal polysaccharide. The reaction with thymus and skin epithelial cells is likely to be bound with high affinity antibodies to the specific determinant of A-polysaccharide.