Production of monoclonal antibodies against the carbohydrate of group A streptococci.

Mouse hybridomas were isolated by fusing P3.X63.Ag8-653 myeloma cells with spleen cells from BDF1 mice repeatedly immunized with Streptococcus pyogenes type 3 ATCC 12384. Two out of 480 growing cultures secreted antibodies against the bacterial strain used as immunogen, as evaluated by an ELISA assay. After cloning the most representative continuously growing clone, 1-181, the binding specificity of these monoclonal antibodies was determined using either Streptococci with carbohydrate of different group or different bacteria strains. Binding properties suggest that the 1.181 monoclonal antibodies specifically recognize the carbohydrate moiety of Streptococci group A.