An enzyme-linked immunosorbent assay (ELISA) for the detection of antibodies to Anaplasma centrale and Anaplasma marginale.

An enzyme-linked immunoassay (ELISA) was applied to detect antibodies to A. centrale and A. marginale using homologous and heterologous antigens. The assay was compared with the indirect fluorescent antibody (IFA) test, and although a similar degree of sensitivity was obtained, the ELISA test had several advantages. Partially purified Anaplasma initial bodies used for antigen preparations contained negligible amounts of residual erythrocytic material, and did not interfere with the specificity of the ELISA. The antigenic similarity between A. marginale and A. centrale was further substantiated by cross-reactivity obtained with heterologous antigens in both ELISA and IFA tests, and antibodies produced during natural infection with A. marginale were indistinguishable in both tests from those produced following vaccination with A. centrale.