Abstract
Minute amounts of M protein were detected in culture supernates of virulent Group A streptococci by type-specific inhibition of the long chain and the bactericidal tests for anti-M antibody. The amount of M protein that was detected by the inhibition of these biological systems was less than could be demonstrated by precipitation tests. All strains of streptococci rich in M protein which were studied formed long chains when grown in sufficient concentrations of anti-M antibody. Very low concentrations of anti-M antibody escaped detection by the long chain test when strains of excessive M protein content were employed. Under such conditions the bactericidal test detected anti-M antibody more sensitively than the long chain test owing to the smaller inoculum employed in the former method. The scission of streptococcal chains may be inhibited by union of antibodies with surface antigens other than M protein. Long chains were formed when M-negative, R-positive strains were grown in sera containing anti-R antibody.
Full Text
The Full Text of this article is available as a PDF (670.0 KB).
Selected References
These references are in PubMed. This may not be the complete list of references from this article.
- EKSTEDT R. D., STOLLERMAN G. H. Factors affecting the chain length of group A streptococci. I. Demonstration of a metabolically active chain-splitting system. J Exp Med. 1960 Oct 1;112:671–686. doi: 10.1084/jem.112.4.671. [DOI] [PMC free article] [PubMed] [Google Scholar]
- LANCEFIELD R. C. Differentiation of group A streptococci with a common R antigen into three serological types, with special reference to the bactericidal test. J Exp Med. 1957 Oct 1;106(4):525–544. doi: 10.1084/jem.106.4.525. [DOI] [PMC free article] [PubMed] [Google Scholar]
- STOLLERMAN G. H., EKSTEDT R. Long chain formation by strains of group A streptococci in the presence of homologous antiserum: a type-specific reaction. J Exp Med. 1957 Sep 1;106(3):345–356. doi: 10.1084/jem.106.3.345. [DOI] [PMC free article] [PubMed] [Google Scholar]
- STOLLERMAN G. H., KANTOR F. S., GORDON B. D. Accessory plasma factors involved in the bactericidal test for type-specific antibody to group A streptococci. I. A typical behavior of some human and rabbit bloods. J Exp Med. 1958 Oct 1;108(4):475–491. doi: 10.1084/jem.108.4.475. [DOI] [PMC free article] [PubMed] [Google Scholar]
- STOLLERMAN G. H., SIEGEL A. C., JOHNSON E. E. Evaluation of the "long chain reaction" as a means for detecting type-specific antibody to group a streptococci in human sera. J Exp Med. 1959 Dec 1;110:887–897. doi: 10.1084/jem.110.6.887. [DOI] [PMC free article] [PubMed] [Google Scholar]