Purification of somatic antigens from Paracoccidioides brasiliensis. Preliminary study

Abstract

We describe the procedures followed to purify antigenic fractions from P. brasiliensis sonicated whole yeast cells. By means of the agar gel immunodiffusion test, antigen-antibody complexes were allowed to produce precipitin lines; these were further separated, eluated and two antibody-free antigenic fractions were further purified by column chromatography and polyacrilamyde gel electrophoreses. These fractions proved to be proteins with molecular weights of 66 and 85 kd; the former reacted with specific antisera and produced a precipitin line identical to one of the three formed by the total antigen. Results indicate that it would feasible to obtain purified, chemically characterized antigens. These could, in the future, bring improvement in the serologic diagnosis of paracoccidioidomycosis as only those specific components of known serologic reactivity would be employed.