Existence of multiple immunodeterminants in the type-specific capsular substance of group B type Ia streptococci

Abstract

Rabbits immunized with group B, type Ia streptococci produce two distinct populations of protective antibodies. Evidence is presented indicating that these antibodies are directed against two major immunodeterminants which coexist in the specific type Ia antigen. Immunochemical data, using purified antibody preparations, indicate that the type substance, a sialic acid polymer consisting of galactose, glucose, glucosamine, and sialic acid, possesses two distinct immunodominant determinants, terminal sialic acid residues and a galactosyl oligosaccharide. Antibodies directed against either of these determinants were shown to possess in vivo and in vitro opsonic capabilities.

Capsular antibodies induce type-specific phagocytosis of capsulated Staphylococcus aureus by human polymorphonuclear leukocytes

“…56, 1988 1092 KARAKAWA ET AL. Teichoic acidb NDC a Antibodies were measured by the quantitative precipitin method (10,11). b Antibodies were prepared from rabbits immunized with noncapsulated S. aureus 1. lated and de-O-acetylated CPS was less effective than anti-83 serum in inducing phagocytosis by PMN, despite its higher total CPS antibody level (Tables 2 and 3).…”

“…Similar results on the multiplicity of epitopes on a CPS have been reported for both native and desialylated type 3 and type 1 group B hemolytic Streptococcus spp. (10,18). In the case of type 1, group B Streptococcus spp., antibodies directed against the native sialylated CPS were more effec-FIG.…”

“…Equal volumes (0.1 ml) of antiserum and antigen were mixed and stored at 37°C for 1 h and overnight in the cold. The reaction mixtures were centrifuged and washed as described previously (10). The anti-capsular polysaccharide antibody concentration was determined by measuring the protein of the washed precipitates by the modified Lowry method with bovine serum albumin as a reference standard.…”

“…CPS antibodies were measured by quantitative precipitin analysis (10,12). The amount of precipitated antibodies was assayed by a modification of the Lowry method (10). Double immunodiffusion was performed in 0.7% agarose (BBL Microbiology Systems, Cockeysville, Md.…”

The type-specific polysaccharides of Streptococcus suis.

“…S. suis type 1 streptococci elicit in pigs antibodies that protect against infection type specifically (5), but this has yet to be confirmed with type 2 . Group B streptococci induce in rabbits antibodies that protect mice type specifically (17) ; some of the group B type-specific polysaccharides appear capable of eliciting antibodies with more than one homologous specificity directed against different parts of the same molecule (14,15) .…”