The resistance of C57BL/6 mice to subcutaneous infection with Mycobacterium lepraemurium is dependent on both T cells and other cells of bone marrow origin.

Thymectomized or sham-thymectomized C57BL/6 mice were irradiated and reconstituted with either C57BL/6 bone marrow cells or bone marrow cells from H-2 matched BALB/B mice. The ability to limit organism multiplication at the site of infection in response to a moderate dose of Mycobacterium lepraemurium is shown to be T-cell mediated and not dependent on the type of bone marrow cells used for reconstitution. Dissemination of the organisms on the other hand appeared to be dependent on both T cells and cells of bone marrow origin.

Role of the major histocompatibility complex in resistance and granuloma formation in response to Mycobacterium lepraemurium infection.

Resistance to a subcutaneous infection with a moderate dose of Mycobacterium lepraemurium was investigated in C57BL/6 mice and in three congenic strains with the BALB background (BALB/c, BALB/B, and BALB/K). Resistance after 10 weeks of infection was found not to be linked to the major histocompatibility complex. The ability to develop a delayed hypersensitivity response to an ultrasonicate of M.

The histopathology of tissues in "resistant" and "susceptible" strains of mice infected with a moderate dose of Mycobacterium lepraemurium.

A systematic study by light and electron microscopy of tissues from BALB/c and C57BL/6 mice infected subcutaneously with 10(7) Mycobacterium lepraemurium organisms was carried out at various times throughout the infection. The relatively resistant C57BL/6 mice had an earlier inflammatory response at the site of the infection than did the susceptible BALB/c mice. The infiltration in the former strain contained fibroblast-like cells and epithelioid cells early on in the infection.

H-2 linkage control of resistance to subcutaneous infection with Mycobacterium lepraemurium.

The H-2 linkage of the gene or genes controlling resistance to subcutaneous infection with 10(7) Mycobacterium lepraemurium organisms was investigated by using H-2 congenic strains on BALB and B10 backgrounds. Resistance was assessed by counting the organisms present at the infection site in the footpad and in the draining (right popliteal) lymph node 20 weeks after infection. When mice of BALB and B10 backgrounds with the same H-2 haplotype were compared, the BALB mice were always more susceptible.