The occurrence of two M antigens in certain group A streptococci related to type 14.
A strain of Group A streptococcus previously considered to belong to Type 14 was shown to have two immunologically distinct M antigens, designated Type 14 and Type 51. Most strains having the Type 14 M antigen were found to have also the Type 51 M antigen, and are considered to belong to Type 14-51. Four strains had the Type 51 M antigen without the Type 14 M antigen and one strain had the Type 14 M antigen without the Type 51 M antigen. The failure of a variant to produce the known M antigen of the parent strain does not necessarily mean that the strain is M(-), because a second M antigen may be present as was the case in several strains described here.
D000941:Antigens; D001324:Autoantigens; D006801:Humans; D013291:Streptococcus / Q000276:immunology*; D013297:Streptococcus pyogenes
D000941:Antigens; D001324:Autoantigens
ANTIGENS; STREPTOCOCCUS/immunology