Monoclonal T-cell Receptor Research Articles

Clonal expansion of T cells following in vitro stimulation with autologous melanoma cells and interleukin-2 studied by molecular analysis of a T cell receptor

Twelve autologous mixed peripheral blood (PBL) tumor cell interactions (MLTC) followed by in vitro expansion of the stimulated T cells in recombinant interleukin-2 (IL-2) were analyzed for the potential emergence of oligoclonal or monoclonal T cell populations in the PBL by Southern blot analysis of the T cell receptor (TCR) beta gene. The emergence of oligoclonal or monoclonal TCR beta gene rearranged populations was seen in 5 of the 12 cases. In 2 of these 5 cases only one dominantly rearranged band was observed. The emergence of oligoclonal or monoclonal T cell populations following stimulation with autologous melanoma cells was associated with predominant CD4 phenotype of the stimulated PBL exhibiting a varied degree of cytotoxicity toward the respective autologous melanoma cells. The evidence of emergence of monoclonal or oligoclonal T cell populations following stimulation with autologous tumor cells strongly supports the existence of T cell-mediated responses against autologous melanomas. Furthermore, cellular and molecular analyses of T cell responses in autologous mixed lymphocyte tumor cell interactions will provide valuable information on the nature of the T cell responses and on the pattern of gene segment usages by the T cells in response to the autologous tumor cells.

“Intravascular lymphomatosis” (angioendotheliomatosis): Evidence for a T-cell origin in two cases

Intravascular lymphomatosis (IL) is a rare and potentially fatal multifocal intravascular proliferative disorder, most often involving the skin and the central nervous system. Originally considered an endothelial disorder, IL has recently been reclassified as an angiotropic lymphoma, most often of B-cell origin. We report immunocytochemical and ultrastructural findings in two patients with IL, both representing angiotropic T-cell lymphomas. In one patient, lesional tissue was examined by Southern blot analysis and monoclonal T-cell receptor rearrangement was found. As an additional feature in one patient, a myelosuppressive serum factor was demonstrated in peripheral blood progenitor cell cultures as the cause of underlying chronic anemia and leukopenia; this factor is thought to be a cytokine product of the lymphoma cells.