The Cellular Antigens of Group a Streptococci

Abstract

The immunoelectrophoretic characteristics of the known cellular antigens of serotype 17, Group A streptococci have been presented. These include C, M, T, and polyglycerophosphate. In addition, three hitherto undescribed antigens of serotype 17 have been encountered. The F antigen occurs in most serotype 17 strains, has a faster electrophoretic mobility than M, appears in acid, distilled water, and other extracts of harvested cells, is released from the cells in large quantity into the culture medium during growth when the pH is maintained at 7.3 or over, is probably protein in nature, and may play a minor role in mouse virulence of serotype 17 strains. Its antibodies do not confer bactericidal power on human blood. The E antigen is serotype-specific and is closely associated with the M antigen. The suggestion is made here that E is a part of the M molecule, acquiring independent electrophoretic mobility when separated from the rest of the M molecule by acid hydrolysis and carrying an antigenic determinant serologically distinct from the determinant on the rest of the M molecule. E can be recognized only by immunoelectrophoresis. Its role, if any, in virulence has not been established. The third antigen, E4, is a non-serotype-specific antigen found in most serological groups and types of hemolytic streptococci. It is serologically related to polyglycerophosphate, but its chemical nature has not been determined. It appears to be unrelated to virulence.

Acrylamide Gel Electrophoresis of Group A Streptococcal Cell Walls

“…wall proteins, such as T and R, have been described (4,11). The present investigation showed that patterns obtained by acrylamide gel electrophoresis of streptococcal cell walls were characteristic for selected M types of group A streptococci.…”

Persistence of Streptococcal Group a Antibody in Patients With Rheumatic Valvular Disease

“…The occurrence of antibodies to streptococcal Group A carbohydrate in man has been described by several authors (4)(5)(6)(7)(8). Halpern human sera (6).…”

Neonatally induced transplantation tolerance: in vitro evidence supporting a clonal inactivation mechanism

“…Since Ig receptors are essential for antigen recognition [3], it has been suggested that their loss, as a result of antigendriven maturation, could cause a reduction in the capacity of lymphocytes t o make contact with and be stimulated by anti- Attempts have previously been made t o define intracellular molecular changes which probably occur concurrently with the loss of immunoglobulin receptors, after the first antigen contact. Autoradiographic studies during immunocyte maturation have demonstrated a shift from blast cells, intensively synthesizing RNA, to plasma cells, actively synthesizing protein, without concommitant RNA synthesis [8,9]. This shift was further analyzed by examining the Actinomycin D sensitivity of antibody-producing cells in chicken spleen fragment cultures at various times after in v i v o immunization [ 101.…”