Cellular and Cytokine Responses in the Granulomas of Asymptomatic Cattle Naturally Infected with Mycobacterium bovisin Ethiopia

Cell (CD3+T cell and CD68+macrophages), cytokine (interferon gamma-positive [IFN-?+] and tumor necrosis factor alpha-positive [TNF-a+]), and effector molecule (inducible nitric oxide synthase-positive [iNOS+]) responses were evaluated in the lymph nodes and tissues of cattle naturally infected with Mycobacterium bovis. Detailed postmortem and immunohistochemical examinations of lesions were performed on 16 cows that were positive by the single intradermal cervical comparative tuberculin (SICCT) test and that were identified from dairy farms located around the city of Addis Ababa, Ethiopia.