Effect of staphylococcal alpha-toxin on neutrophil migration and adhesiveness

The effect of staphylococcal alpha-toxin on the chemotactic response of human polymorphonuclear leukocytes was studied by measuring the migration of alpha-toxin-treated cells either through membrane filters toward C5a or under agarose toward N-formyl-l-methionyl-l-phenylalanine. At doses of greater than or equal to 5 hemolytic units, alpha-toxin depressed chemotactic responsiveness in both best systems. Further studies revealed that alpha-toxin was also a potent granulocyte aggregant at doses similar to those necessary for depressed chemotactic capacity. It is proposed that the inhibitory effect of this membrane-active toxin on chemotactic function may be related to increased granulocyte adhesiveness and that the pathogenic properties of alpha-toxin may in part by explained by these effects.