Western blot analysis of concentrated culture supernatant of GAS strain Sa with the anti-SLO antibody. Culture supernatant was approximately 1,000~2,000 fold concentrated from culture medium by ammonium fractionation and heat-precipitation. Lane 1; Concentrated culture of GSA strain Sa Lane 2; Concentrated medium only

Western blot analysis of culture supernatant from GAS strain Sa and GCS strain H46A with the anti-SLO antibody. Lane 1; Medium only Lane 2*; Culture supernatant of GAS strain Sa Lane 3**; Culture supernatant of GCS strain H46A The antibody was used at 1/2,000 dilution * Most of SLO in culture medium of GAS strain Sa is proteolytically degraded, accounting for low activity level of SLO in the culture of this strain. Condensed sample is analyzed in Fig. 2. ** The two faint bands below SLO band are partially degraded SLO.