Immunochemical studies on burro antibodies to Histoplasma capsulatum.

Burro antiserum to Histoplasma capsulatum was studied from the viewpoint of precipitating antibody distribution among euglobulins, pseudoglobulins, and immunoglobulin classes. By immunodiffusion analysis it was determined that throughout immunization most of the antibody was euglobular, but there was an increase in pseudoglobular antibody as immunization progressed. By immunoelectrophoretic and immunodiffusion analyses of specifically purified antibody, and antibody non-specifically fractionated by column chromatography and ultracentrifugation, it was established that there was no demonstrable IgM antibody, that most of the antibody appeared to be IgG, and that a gamma1 immunoglobulin, probably IgA or T-globulin, may have been responsible for some of the activity. No major changes in the distribution of antibody among immunoglobulin classes seemed to occur during immunization.