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.

Persistence of type-specific antibodies in man following infection with group A streptococci.

Whole blood or sera were collected from individuals who had had infections with Group A streptococci of known serological type as long ago as 10 to 32 years. Most of these patients had not been treated with chemotherapeutic drugs. By means of bactericidal tests with all these sera, and mouse protection tests with some, type-specific antibodies could be demonstrated in at least half of them after a lapse of many years, the longest interval being 32 years.

Occurrence of R antigen specific for Group A type 3 streptococci.

Approximately 50 per cent of Group A, Type 3 streptococci contain a hitherto undescribed antigen found only in Group A, Type 3 organisms. It is serologically distinct from Type 3 M antigen and is designated as 3 R antigen. Strains containing 3 R antigen but no Type 3 M antigen are "glossy," avirulent Type 3 variants.

Differentiation of group A streptococci with a common R antigen into three serological types, with special reference to the bactericidal test.

In further study of streptococci having the R antigen, the bactericidal test has been used instead of the mouse protection test in investigating the type-specific M antigens of these organisms. The results have been confirmed by M anti-M precipitin tests, and a correlation between the M and T antigens of the strains has been shown. On the basis of a specific M antigen, type 28 has been shown to comprise Griffith's strain Small and four other R-containing strains.

Variation in the group-specific carbohydrate of group A streptococci. I. Immunochemical studies on the carbohydrates of variant strains.

The phenomenon of apparent loss of group-specific carbohydrate in the course of mouse passage of group A streptococci has been subjected to further study, and several additional variants showing this property have been described. The loss of group reactivity is shown to be due to an alteration in the chemical structure and serological specificity of the cell wall carbohydrate. This alteration appears to be essentially the same in each of the variants available for study.

Preparation and properties of a protein (R antigen) occurring in streptococci of group A, type 28 and in certain streptococci of other serological groups.

A group A, type 28 protein antigen, resistant to tryptic digestion and previously considered to be a type-specific substance, was purified and its chemical and immunological properties studied. This protein lacks the characteristic properties of a type-specific M antigen since it is apparently unrelated to virulence and does not induce the formation of protective antibodies although precipitins are readily produced. It is designated the R antigen.

Preparation and properties of type-specific M antigen isolated from a group A, type 1 hemolytic streptococcus.

Type-specific M antigen was extracted by heating type 1 group A streptococci at pH 2 in a boiling water bath. The protein was then purified by digestion with a preparation of crystalline ribonuclease which was free of proteolytic activity. It was further purified by fractional precipitation with (NH(4))(2)SO(4).

THE PROPERTIES OF T ANTIGENS EXTRACTED FROM GROUP A HEMOLYTIC STREPTOCOCCI.

1. T antigens of group A hemolytic streptococci have been obtained in soluble form by digestion of the bacterial cells with pepsin or trypsin. Large quantities of this antigen were readily extracted from type 1 strains, whereas only small amounts could be obtained from strains of other types.

STUDIES ON THE ANTIGENIC COMPOSITION OF GROUP A HEMOLYTIC STREPTOCOCCI : IV. RELATED T BUT DISTINCT M ANTIGENS IN TYPES 15, 17, 19, 23, 30, AND IN TYPES 4, 24, 26, 28, 29, 46. IDENTIFICATION BY SLIDE AGGLUTINATION.

1. The occurrence of closely related T antigens in the series composed of types 15, 17, 19, 23, and 30 accounts for most of the cross reactions observed among these types. Similarly T antigens, unrelated to the first series but mutually related, occur in a second series comprising types 4, 24, 26, 28, 29, and 46.

STUDIES ON THE ANTIGENIC COMPOSITION OF GROUP A HEMOLYTIC STREPTOCOCCI : III. TYPES WITH SEROLOGICALLY IDENTICAL M BUT DISTINCT T ANTIGENS: TYPES 10 AND 12.

1. In this study a series of experiments showing the antigenic relationship of type 10 and type 12 group A hemolytic streptococci is reported. Agglutinin, precipitin, and passive protection tests with unabsorbed and reciprocally absorbed antisera were employed to show that representative type 10 and 12 strains contain serologically identical M antigens but unrelated type-specific T antigens.

STUDIES ON THE ANTIGENIC COMPOSITION OF GROUP A HEMOLYTIC STREPTOCOCCI : II. THE OCCURRENCE OF STRAINS IN A GIVEN TYPE CONTAINING M BUT NO T ANTIGEN.

1. Group A hemolytic streptococci have been described which do not agglutinate in anti-T serum because they lack T antigen. 2.

STUDIES ON THE ANTIGENIC COMPOSITION OF GROUP A HEMOLYTIC STREPTOCOCCI : I. EFFECTS OF PROTEOLYTIC ENZYMES ON STREPTOCOCCAL CELLS.

1. Proteolytic enzymes destroy the type-specific M antigen of group A hemolytic streptococci not only when the M substance is contained in cell-free extracts but also when it is a component of the living cell. 2.

TYPING GROUP A HEMOLYTIC STREPTOCOCCI BY M PRECIPITIN REACTIONS IN CAPILLARY PIPETTES.

A method is described for performing type-specific anti-M precipitin tests on group A hemolytic streptococci in 1 mm. capillary pipettes. These tests require so much less precipitating serum than was formerly used that the method now seems to be practical.

THE SIGNIFICANCE OF M AND T ANTIGENS IN THE CROSS REACTIONS BETWEEN CERTAIN TYPES OF GROUP A HEMOLYTIC STREPTOCOCCI.

In any one strain the occurrence of the previously recognized type-specific protein, M, is usually completely correlated with the presence of the recently recognized type-specific antigen, T. Strain C203 is exceptional in having the T substance of type 1 as well as the two type-specific antigens, M and T, characteristic of type 3. It does not have the M antigen of type 1.

TYPE-SPECIFIC ANTIGENS, M AND T, OF MATT AND GLOSSY VARIANTS OF GROUP A HEMOLYTIC STREPTOCOCCI.

1. Two qualitatively different type-specific antigens, designated M and T, have been found present in matt variants of group A hemolytic streptococci, but only one of these, the T antigen, occurs in the degraded glossy variant. 2.