Effect of streptolysin S on responsiveness of polymorphonuclear leucocytes

Most strains of Streptococcus pyogenes [group A, beta-haemolytic] contain a potent leukotoxic factor. When bacteria containing relatively large quantities of this factor are ingested by or come into contact with Poly Polymorphonuclear Leucocytes [PMNs], the neutrophils are destroyed. Death of PMNs is associated with intracytoplasmic rupture of PMN granules; this release of granule contents is thought to be the leukocidal killing mechanism. Purified, Streptolysins S [SLS], at concentrations of b etween 8000 HU/ml, when added directly to zymosan - induced rabbit PMNs, caused iinhibition of the PMNs chemiluminescence response