Inhibition of staphylococcal alpha-hemolysis by monoclonal antibodies against oligomer 12 S alpha-toxin.

Oligomer 12 S alpha-toxin as well as 3 S alpha-toxoid of Staphylococcus aureus induced the formation of monoclonal antibodies (mabs). Mabs against the 12 S alpha-toxin could be demonstrated in 31 and those against 3 S alpha-toxoid in 18 of 120 hybrid cell colonies. Each of these mab-preparations reacted with 12 S, 3 S alpha-toxin and 3 S alpha-toxoid. The reactions were more pronounced with the homologous than the heterologous toxin preparations. Mabs against 12 S alpha-toxin inhibited the hemolytic effects of native 3 S alpha-toxin as well or better than the respective polyclonal antisera.