The Titration of Alpha and Beta Haemolysins in Staphylococcal Toxin

[摘要] The haemolytic action of staphylococcal toxin on human erythrocytes has been described. It is a “hot-cold” lysin.This haemolysin is antigenically distinct from the Alpha haemolysin, and is probably identical with the Beta toxin of Glenny and Stevens. The only material difference between our haemolysin and that described by Glenny and Stevens is that ours lyses rabbit cells.The presence of more than a certain concentration of Beta toxin lowers the apparent titer of Alpha antihaemolysin in terms of Provisional International Units and is therefore misleading. The converse is also true. It would seem essential to take this into account in the haemolytic method of assaying therapeutic antisera as a standard.The mutual interference of Alpha and Beta toxin in the titration of antitoxin can be eliminated by suitable dilution of selected toxins, but this method is limited by the concentration needed to give accurate results. This method is of least value in titrating Alpha antitoxin because of the susceptibility of rabbit cells to Beta toxin, and it is most desirable to use a pure Alpha toxin.The use of human erythrocytes in the titration of Beta toxin and Beta antitoxin has great advantages over the use of sheep erythrocytes. They show considerable resistance to the Alpha haemolysin whereas sheep cells are very susceptible to it. This being so, impure toxins can be used to titrate any Beta antitoxin if the test dose of toxin used contains less than one LH dose of the Alpha toxin.

[学科分类] 生物科学（综合）