Transfer of delayed hypersensitivity to leishmanin (Montenegro reaction)

Abstract It was possible to transfer the cutaneous leishmanin hypersensitivity (Montenegro reaction) to 7 out of 12 recipients. The diameter of the indurations observed ranged from 8 to 25 mm. Histological examination of skin biopsies from the site of three positive Montenegro reactions showed intense mononuclear infiltrate of lymphocytes and histiocytes, and one biopsy showed the feature of tuberculoid granuloma. Four recipients retested with leishmanin after 11, 22, 25, and 32 days, still showed positive reactions.