Abstract
The protein, polysaccharide and phospholipid constituents of Nocardia asteroides have been partially purified and their immunogenicity studied in mice. Humoral and cellular immune responses were demonstrated against a crude cytoplasmic protein fraction (CPF). Two fractions of CPF were prepared on a Sephadex G-200 column; a high mol. wt fraction, fraction-1(F1) was capable of eliciting both types of immune responses, whereas fraction-2(F2) behaved more like a hapten. Phosphatides elicited only humoral responses whereas polysaccharides were non-immunogenic.