Effect of Escherichia coli alpha-hemolysin on human peripheral leukocyte function in vitro.
To gain further evidence for the role of the Escherichia coli alpha-hemolysin in pathogenesis, its in vitro effects on human peripheral leukocyte function were studied. Leukocytes exposed to low doses of alpha-hemolysin responded with a marked chemiluminescence response, indicating activation of oxidative metabolism. This response was time and dose dependent. Pretreatment of leukocytes with doses of alpha-hemolysin at which nearly 80% of the cells survived decreased the ability of the cells to phagocytize bacteria and particles and to undergo chemotaxis. Premature activation of leukocytes and inhibition of phagocytosis and chemotaxis by alpha-hemolysin, if they occur in vivo, would greatly enhance the survival of an invading E. coli strain.
D002634:Chemotaxis, Leukocyte; D004305:Dose-Response Relationship, Drug; D004926:Escherichia coli / Q000032:analysis*; D006460:Hemolysin Proteins / Q000494:pharmacology*; D006801:Humans; D066298:In Vitro Techniques; D007700:Kinetics; D007962:Leukocytes / Q000502:physiology*; D008163:Luminescent Measurements; D008213:Lymphocyte Activation; D010587:Phagocytosis
D006460:Hemolysin Proteins