BACILLUS CALMETTE-GUERIN (BCG) DECREASES RESISTANCE TO LISTERIA-MONOCYTOGENES INFECTION IN MICE

  • 1 January 1981
    • journal article
    • research article
    • Vol. 44  (3) , 509-515
Abstract
BCG inoculation has been shown to inhibit certain immune functions. To determine whether this inhibition adversely affects host defenses against infection, the effect of BCG on Listeria infection in mice was investigated. Mice were injected i.v. with L. monocytogenes and 24-96 h later were inoculated with 8 .times. 106 BCG. Mice given BCG and Listeria had a greater mortality and higher spleen Listeria counts than mice given Listeria alone. An increased number of bacteria in spleens was noted as early as 24 h after BCG inoculation. Peritoneal macrophages from mice receiving both organisms had a decreased capacity to kill Listeria in vitro. In addition, BCG inoculation suppressed delayed hypersensitivity responses and in vitro spleen cell proliferative responses to Listeria antigen. Suppression of spleen cell proliferative responses was associated with an adherent, non-T lymphocyte subpopulation. BCG administration seemingly decreases resistance to intracellular pathogens by abrogating normal cellular defenses.