Impairment of T-cell functions with the progressive ascitic growth of a transplantable T-cell lymphoma of spontaneous origin.
It has been observed that the progressive ascitic growth of a transplantable T-cell lymphoma of spontaneous origin, designated Dalton's lymphoma (DL), in a murine host induces inhibition of various immune responses and is associated with an involution of thymus accompanied by a massive depletion of the cortical region and alteration in the distribution of thymocytes caused by tumour serum-dependent induction of apoptosis with a decrease of CD4(+)CD8(+), CD4(+)CD8(-) and CD4(-)CD8(+) thymocytes. Here, we report that thymocytes of DL-bearing mice are defective in their proliferative ability and in their response to non-specific mitogenic stimulus in vitro. Also, antigen-specific T-cell proliferative ability representing the fundamental T(H) function declines under DL-bearing conditions and upon treatment with serum of DL-bearing mice. Moreover, a significant inhibition of T-cell cytolytic activity with a decreased ability to produce interferon gamma is shown by the T cells of DL-bearing mice and by the T cells treated with DL-ascitic fluid, DL-conditioned medium or serum of DL-bearing mice. Further, addition of interleukin-2 and anti-interleukin-10 to the cultures of thymocytes treated with serum of DL-bearing mice is found to inhibit the induction of apoptosis in thymocytes, a phenomenon associated with the progression of DL growth. Analysis of the results indicates an immune deviation with the predominance of a T(H2)-type response with the progression of tumour. We further discuss the possible mechanisms that may explain the observed tumour-induced diminution of T-cell immunity.
Shanker
A
A
School of Biotechnology, Banaras Hindu University, Varanasi, India.
Singh
S M
SM
Sodhi
A
A
D000818:Animals; D001201:Ascites / Q000473:pathology*; D016207:Cytokines / Q000096:biosynthesis; D003602:Cytotoxicity, Immunologic; D005260:Female; D007371:Interferon-gamma / Q000096:biosynthesis; D008213:Lymphocyte Activation; D016399:Lymphoma, T-Cell / Q000276:immunology* / Q000473:pathology*; D008297:Male; D051379:Mice; D008807:Mice, Inbred BALB C; D009368:Neoplasm Transplantation; D013601:T-Lymphocytes / Q000276:immunology*; D013602:T-Lymphocytes, Cytotoxic / Q000276:immunology; D018417:Th1 Cells / Q000276:immunology; D018418:Th2 Cells / Q000276:immunology; D013950:Thymus Gland / Q000166:cytology / Q000276:immunology
D016207:Cytokines; D007371:Interferon-gamma