Experimental infection with Mycobacterium kansasii in athymic nude mice

Subcutaneous infection with Mycobacterium kansasii did not cause mortality in athymic nu/nu and control nu/+ mice. It had a stimulatory activity comparable to obligatory mycobacterial pathogens: thymus-dependent lymphatic tissues areas were populated during the infection by lymphocytes also in nu/nu mice in which a low degree of migration inhibition factor production could be seen. In both models of chief site of mycobacterial trapping and phagocytosis was the hyperplastic interdigitating cell mesh in the thymus-dependent areas of lymph nodes. A detailed morphological description of the organ changes is given.