CD8+ T cells in Hodgkin's disease tumor tissue are a polyclonal population with limited clonal expansion but little evidence of selection by antigen

A minor component (about 25%) of lymphocytes in Hodgkin's disease (IID) are CD8(+) T cells. It is unclear whether the presence of these cells reflects an. antitumor cytotoxic response. The goal of the present study was to investigate clonal composition and the T cell receptor (TCR) beta repertoire of the CD8+ T cell population ill IID, Single CD8(+) cells were micromanipulated from frozen tissue sections of lymph nodes affected by primary ND and subjected to single target amplification of TCR beta gene rearrangements. Sequence analysis of the V region genes revealed the presence of expanded CD8(+) T cell clones in all three cases analyzed. Most of these clonal expansions accounted for less than 10% of the CD8(+) T cell population. In one case, 30% of the CD8(+) T cells belonged to one or two clones. Comparison of V region sequences, however, did trot provide evidence that the micromanipulated CD8(+) cells were sampled from a population that was selected for particular antigen specificities, No obvious biases in TCR V beta and J beta gene segment usage or CDR3 length distribution were found. Similarities of CDR3 amino acid sequences as found In selected CDR3 structures were rare. These results suggest that, like CD4(+) T cells, CD8(+) T cells may also be recruited into the tumor tissue in an antigen-nonspecific manner.