Cell-mediated immune responses to Babesia bovis merozoite antigens in cattle following infection with tick-derived or cultured parasites

• Published in: Infection and Immunity Vol. 59; no. 7; pp. 2418 - 2426
• Main Authors: Brown, W.C. (Texas AandM University, College Station, TX), Logan, K.S, Wagner, G.G, Tetzlaff, C.L
• Format: Journal Article
• Language: English
• Published: Washington, DC American Society for Microbiology 01.07.1991
• Subjects: Animal protozoal diseases; Animals; Antibodies, Protozoan - immunology; ANTIGENE; ANTIGENOS; Antigens, Protozoan - immunology; Babesia - immunology; BABESIA BOVIS; Babesiosis - immunology; Biological and medical sciences; Blotting, Western; BOOPHILUS MICROPLUS; BOVIN; Cattle; Cattle Diseases - immunology; Cattle Diseases - parasitology; CULTIVO IN VITRO; CULTURE IN VITRO; ERITROCITOS; ERYTHROCYTE; EXPERIMENTACION IN VIVO; EXPERIMENTATION IN VIVO; GANADO BOVINO; IMMUNISATION; IMMUNITE CELLULAIRE; Immunity, Cellular; Indomethacin - pharmacology; INFECCION; INFECTION; Infectious diseases; INMUNIDAD CELULAR; INMUNIZACION; LINFOCITOS; LYMPHOCYTE; Lymphocyte Activation; Macrophages - immunology; Medical sciences; Monocytes - immunology; Parasitic diseases; PODER PATOGENO; POUVOIR PATHOGENE; Protozoal diseases; REPONSE IMMUNITAIRE; RESPUESTA INMUNOLOGICA; Solubility; T-Lymphocytes - immunology; Time Factors; Cell proliferation; Protozoa; Protozoal disease; Immune response; Bovine; Monocyte; Cellular immunity; Babesiasis; Veterinary medicine; Infection; Antigen; Vertebrata; Experimental disease; Mammalia; T-Lymphocyte; Merozoite; Artiodactyla; Babesia bovis; Sporozoa; Ungulata; Macrophage
• ISSN: 0019-9567; 1098-5522
• DOI: 10.1128/IAI.59.7.2418-2426.1991

Peripheral blood mononuclear cells from cattle experimentally infected with Babesia bovis were examined for parasite-specific cell-mediated immune responses. Unfractionated merozoites and soluble and membrane fractions derived from merozoites were all antigenic for immune cattle, although the membrane fraction was the most stimulatory. Cattle responded to different antigenic fractions in a differential manner, and only that animal immunized with autologous cultured parasites responded to parasitized erythrocyte culture supernatants. Plastic-adherent cells (presumably monocytes/macrophages) were required for a proliferative response to babesial antigens but not to the T-cell mitogen concanavalin A, suggesting that babesial proteins are not simply mitogenic for T cells. Lymphocyte responses directed against a different hemoparasite from Mexico, Babesia bigemina, indicate that this parasite shares cross-reactive T-cell epitopes with B. bovis. These studies define a system whereby T lymphocytes from babesia-immune cattle can be used in proliferation assays to identify babesial merozoite antigens which are immunogenic for T cells. Because identification of helper T-cell epitopes is important for the design of a babesial subunit vaccine which will evoke anamnestic responses, the studies described here provide a basis for such experiments