Immunoelectrophoretic Analysis of Streptococcus agalactiae Serotype Ia Antigens

Abstract

Rabbit antibodies to heat-killed whole cells of Streptococcus agalactiae serotype Ia were used to establish an antigen map using Triton X-100 sonicates of homologous cells and crossed immunoelectrophoresis. A total of 11 antigens were identified but the density of immunoprecipitates was varied and only seven could be reliably detected, one of which dominated the immunoprecipitate pattern by its intensity. The antigens were partially characterized by immunological, chemical and cell-location methods. Five of the antigens contained carbohydrate and two of those were sensitive to trypsin and probably represent cellwall compounds. Of the three most prominent antigens, one was surface located and represented the type and shared type antigens (Iabc), one was a cell-wall carbohydrate and very sensitive to periodate, and one was a proteinlcarbohydrate complex which was heat-labile and trypsin sensitive. Group B epitopes were detected in three immunoprecipitates. Cross-reactions between type Ia and other serotypes and streptococci were recorded.

Immunopathological investigations during the course of arthritis induced in rats by Streptococcus agalactiae

“…The methods of Triscott and Davis (1980), and Somerset and Davis (1986) were used to produce antiserum against S. agalactiae O90R and Aeromonas hydrophila.…”