PRODUCTION AND PARTIAL CHARACTERIZATION OF MONOCLONAL-ANTIBODIES AGAINST ERYTHROGENIC TOXINS TYPE-A AND TYPE-C FROM STREPTOCOCCUS-PYOGENES

Hybridoma cell lines producing monoclonal antibodies against streptoco ccal erythrogenic toxins type A and C were established from fusions of immunized BALB/c mice splenocytes with P3X63-Ag8.653 myeloma cells. S ix MAbs recognize ETA and 11 MAbs bind to ETC. Two MAbs (designated ET A-2 and ETC-10) were produced in ascitic fluid and further characteriz ed. ETA-2 (IgG(2a)) binds to ETA with an affinity constant of 1.8 x 10 (10) M(-1) and ETC-10 (IgG(1)) binds to ETC with an affinity constant of 3.5 x 10(9) M(-1). The specificities of the MAbs were evaluated by ELISA and immunoblotting. Both MAbs ETA-2 and ETC-10 are useful in dev eloping specific double-sandwich ELISAs, in which the MAbs were used a s solid-phase capture antibodies for the quantitative determinations o f ETA and ETC.