Circulating and tumor-infiltrating gamma delta T Cells in patients with B-cell lymphomas.

In order to analyze the involvement of gamma delta T cells in the immune surveillance against B cell lymphomas (BCL), we investigated the proportion of circulating gamma delta T cells in 52 BCL patients using two-color flow cytometry, together with tumor-infiltrating gamma delta T cells in 22 of those patients. We found that the proportion of tumor-infiltrating gamma delta T cells in BCL patients was not different from that of lymph node gamma delta T cells in reactive hyperplasia patients. However, a decreased percentage of circulating gamma delta T cells were observed in indolent lymphoma (IL) and limited aggressive lymphoma (AL) patients when compared with normal controls. In contrast, as a result of a histogram, advanced AL patients were divided into two subgroups: the patients with increased circulating gamma delta T cells and those without any increase. However, there was no difference in the clinical features of between the two AL subgroups.