Isolation of type-specific polysaccharide antigen from group B type Ib streptococci.

Group B streptococcus type Ib (strain H36B) was subjected to digestion with extracellular muralytic enzymes prepared from Streptomyces albus. Type Ib-specific polysaccharide antigen was isolated from the lysate by alcohol precipitation and Sepharose 6B chromatography. The purified type Ib antigen has a Kd value of 0.

Teichoic acids of group D streptococci with special reference to strains from pig meningitis (Streptococcus suis).

Immunoelectrophoresis revealed in phenol extracts from S. faecalis and S. faecium a mixture of free and lipid-bound teichoic acids, both reactive with Group D antisera.

Multiple mouse-protective antibodies directed against group B streptococci. Special reference to antibodies effective against protein antigens.

The data presented in this paper establish the finding that multiple specific protective antibodies exist in rabbits in response to immunization with Group B streptococci. The summary in Table I indicates the serological types into which Group B streptococci have been divided on the basis of their antigenic composition. This classification is dependent upon passive protection of mice with antibodies directed against the specific antigens, and types are defined in these terms.

New approaches for the laboratory recognition of M types of group A streptococci.

The successful classification of Group A streptococci by the capillary precipitin technique requires a complete series of M type antisera which are sufficiently potent and specific to give unequivocal type-specific reactions with all the serotypes. Specific antisera for this purpose have been prepared by absorption with heterologous streptococci. Unabsorbed antisera have been employed here in the Ouchterlony double-diffusion agar-gel test to identify the M type of streptococci.