title: Surface membrane components of Theileria spp piroplasms and associated complement fixation activity.
abstract: Theileria parva (parva) piroplasms were examined for complement fixation (CF) activity with sera from cattle immune to T parva (parva) (Muguga). The piroplasms were found to be highly antigenic, and the antigens responsible for this CF reactivity were completely insoluble in aqueous media. The antigens were traced through a variety of fractionation procedures and the fractions examined by electrophoresis in the presence of sodium docedyl sulphate. Antigenically active preparations were found always to contain two polypeptides having molecular weights of 21,500 and 34,000. When intact piroplasms were surface labelled with iodine 125 these same two polypeptides were the most heavily labelled, which suggested that the antigens responsible for the CF reactivity were plasma-membrane bound. Electrophoretic analysis of fractions containing plasma membrane components from piroplasms of three species of Theileria (T parva [parva], T mutans and T taurotragi) enabled interspecific differentiation to be made. Three stocks of T parva (parva) could not be differentiated by this means; such different stocks, from various locations within East Africa, appeared to be identical chemically.
mesh_terms: D000818:Animals; D000941:Antigens / Q000032:analysis; D016782:Apicomplexa / Q000032:analysis / Q000145:classification / Q000276:immunology*; D002417:Cattle; D002462:Cell Membrane / Q000276:immunology; D003168:Complement Fixation Tests; D004591:Electrophoresis, Polyacrylamide Gel; D013801:Theileriasis / Q000469:parasitology
chemical_list: D000941:Antigens