Isolation and partial characterization of culture-derived soluble Babesia bovis antigens.

Immunochemical analyses of soluble antigens derived from microaerophilous stationary phase cultures of Babesia bovis demonstrated that at least three parasite antigens were released in vitro. These antigens have molecular weights within the range of 37,000 to 40,000, fast electrophoretic mobility in the albumin and alpha 1 regions, and are proteinaceous in nature as determined by the sensitivity to proteolytic enzymes trypsin and papain. Purification of these antigens should allow complete characterization of their respective physiochemical and immunogenic properties.