Immunodiagnosis of parasitic zoonoses: sensitivity and specificity of in vitro lymphocyte proliferative responsiveness using nematode antigens purified by affinity chromatography.

The sensitivity of in vitro lymphocyte proliferative responsiveness using antigens purified by affinity chromatography, was greater than that of three serological tests and allowed the specific identification of Dirofilaria immitis, Toxocara canis, Angiostrongylus cantonensis and Ascaris lumbricoides in animals sensitized with parasite antigens, and the diagnosis of natural (D. immitis, T. canis and Angiostrongylus cantonensis) and zoonotic nematode infections. Lymphocytes remained viable in whole blood suspensions in RPM 1640 in a polystyrene insulation box at air temperature for at least 12 hours and reacted in the cell-mediated immunity test (CMIT) without loss of response. The CMIT proved useful in the early immunodiagnosis of nematode infections and showed that parasite antigens purified by affinity chromatography retained a high degree of specificity and sensitivity in both the CMIT and serological tests.