A Complement-fixation Reaction with Haemobartonella muris and Eperythrozoon coccoides

Abstract

HITHERTO no serological reactions were known in Haemobartonella and Eperythrozoon animal infections. In the present study, antigens of H. muris and E. coccoides have been prepared from heavily infected blood cells of splenectomized rats and mice respectively. The blood was hæmolysed by 0.01 M citrate buffer (pH 6), washed three times by centrifugation (10 min. at 4,500 r.p.m.) and resuspended in veronal-buffered saline¹. In the case of E. coccoides a further antigen containing the free organisms could be prepared by spinning the plasma fraction at 6,000 g and using the sediment. The frozen antigens could be stored for a long period without appreciable loss of activity. Immune sera were obtained either from splenectomized rats and mice after recovery from infection or from normal animals 3–5 weeks after intraperitoneal inoculation of parasitized blood. Normal sera were obtained from animals of parasitefree breeds.