Abstract
Alleman AR, Pate MG, Harvey JW, Gaskin JM, Barbet AF (
Cats were experimentally infected with a Florida isolate of Haemobartonella felis in order to collect organisms and evaluate the immune response to H felis. Cryopreserved Florida isolate Haemobartonella felis organisms were thawed and injected by the intravenous route into non-splenectomised or splenectomised cats. The splenectomised cats also received methylprednisolone at the time of inoculation. Blood samples were examined daily for up to 60 days post-infection. H. felis was harvested by differential centrifugation from blood samples collected from splenectomised cats during periods of peak parasitemia. H felis antigens were separated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and transferred to nitrocellulose membranes for immunoblot analysis. Serum samples were collected from the non-splenectomised cats and used for immunoblotting to identify antigens important in the immune response. The combination of splenectomy and corticosteroid treatment caused marked cyclic parasitemia, but without concurrent severe anaemia, thus allowing harvesting of the organism. Several antigens of differing molecular wrights were identified (150, 52, 47, 45, and 14 kDa) and an antigen with a molecular mass of approximately 14 kDa appeared to be one of the most immunodominant being consistently recognised by sera collected at various times during the course of infection. These data suggest that one or more of these antigens might be useful for the serologic diagnosis of H felis infections in cats.