Lysis of human macrophages by cytolytic CD4+ T cells fails to affect survival of intracellular Mycobacterium bovis-bacille Calmette-Guérin (BCG)

Clin Exp Immunol. 1995 Jan;99(1):82-9. doi: 10.1111/j.1365-2249.1995.tb03476.x.


Human CD4+, mycobacteria-specific, cytolytic T cell clones were used to lyse BCG-infected macrophages, and the effect on the subsequent growth and viability of the organisms was examined. The survival of released bacteria following cell lysis was assessed by both 3H-uridine labelling and colony-forming unit (CFU) estimation. The results indicate that even when effective antigen-specific or lectin-mediated cytolysis of the infected macrophages was achieved, there was no evidence for a direct mycobactericidal effect on the intracellular bacteria. This remained the case even if the period of co-culture of T cells and macrophages was extended up to 48 h. Pretreatment of the macrophages with interferon-gamma (IFN-gamma) was not able to act together with T cell-mediated lysis to produce inhibition of mycobacterial growth.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • CD4-Positive T-Lymphocytes / cytology
  • CD4-Positive T-Lymphocytes / immunology*
  • Cells, Cultured
  • Clone Cells
  • Cytotoxicity, Immunologic
  • Humans
  • Macrophages / cytology
  • Macrophages / immunology*
  • Mycobacterium bovis / growth & development
  • Mycobacterium bovis / immunology*