Absorption of Group A Streptococcus Anti-M Typing Sera with Broken Cells

Abstract

Group A streptococcus anti-M typing sera that cannot be made specific by absorption with whole streptococcus cells have been absorbed with the soluble and insoluble fractions of ruptured heterologous cells. The technique has been used successfully for preparing specific anti-M sera against eight serotypes of group A streptococcus. The method involves breakage of the absorbing cells in the presence of the antiserum, and incubation of the mixture at 37 C for 1 hr, followed by 3 to 5 days of incubation at 4 C. The procedure is useful for preparing specific antiserum from certain lots of unabsorbed antiserum that otherwise would have to be discarded because of undesirable cross-reactivity.

M proteins of group A streptococci.

“…In addition to the above procedures, several methods have been devised for typing group A streptococci by immunofluorescence (82,134,163) and immunodiffusion on cellulose acetate (11). A number of papers have also appeared describing procedures to improve the production and specificity of M-typing antisera by variations in immunization schedules and serum absorption (3,8,34,63,102,134).…”