Virus-specific T cell response prevents lymphoma development in mice infected by intrathymic inoculation of Moloney leukaemia virus (M-MuLV).
Previous work on mice neonatally injected with Moloney-murine leukaemia virus (M-MuLV) had shown that T cell lymphoma development correlates with virus infection of lymphoreticular cells (T and B lymphocytes and macrophages) as well as with a lack of generation of virus-specific cytotoxic T lymphocytes (CTL) due to clonal deletion of CTL precursors. In the present report, viral antigen expression and T cell response in mice injected as adults with M-MuLV intrathymus (i.t.) was investigated. Only thymic and splenic T lymphocytes from these mice express virus-induced antigens since they were lysed by virus-specific CTL, and stained by anti-M-MuLV fluorescent serum. In addition, the percentage of M-MuLV-infected T cells increased with increasing post- inoculation times. However, these mice could mount a strong cellular immune response against M-MuLV-infected cells, as detected by massive mixed leucocyte tumour cell culture and by evaluation of virus- specific CTL precursor frequency. Finally, i.t. injected mice were not viraemic and did not develop lymphomas during an observation period of 12-15 months. These data, in contrast with the recent hypothesis that T cell lymphoma development depends on a chronic stimulation of virus-specific T lymphocytes, indicate that the cellular immune response is sufficient for prevention of neoplastic transformation, despite a persistent viral infection of the thymus and peripheral T lymphocytes.
D000818:Animals; D000956:Antigens, Viral / Q000276:immunology; D002471:Cell Transformation, Neoplastic; D007942:Leukemia, Experimental / Q000276:immunology*; D007958:Leukocyte Count; D007959:Lymphocyte Culture Test, Mixed; D008223:Lymphoma / Q000276:immunology*; D051379:Mice; D008810:Mice, Inbred C57BL; D008979:Moloney murine leukemia virus / Q000276:immunology; D013601:T-Lymphocytes / Q000276:immunology*; D013602:T-Lymphocytes, Cytotoxic / Q000276:immunology; D013950:Thymus Gland / Q000276:immunology
D000956:Antigens, Viral