[In vitro production of gamma/delta T cell clones and their characteristics]

Human TCR gamma/delta cell clones were produced from both CD2-depleted normal peripheral blood mononuclear cells (PBMC) and leukemia and lymphoma cell-predominant PBMC, effusion cells and lymph node cells in in vitro cultures with rIL-1 and rIL-2 and using limiting dilution techniques. These clones were then analyzed as to their cell morphology, phenotype and non-major histocompatibility-restricted cytotoxicity (NMRC) to K562. The results of the cloning from CD2-depleted PBMC showed 112 WT31+ gamma/delta-1- clones, 62 WT31- gamma/delta-1+ clones and 101 WT31- gamma/delta-1- clones. These were produced in 17 serial experiments. The addition of EBV-infected B cell line cells as feeder cells resulted in better production of gamma/delta-1+ and non-T cell clones than that of WT31+ clones. One typical example of the cloning from lymphoblastic lymphoma cell-predominant PBMC resulted in the production of 8 gamma/delta-1+ and 3 WT31+ clones. Most of the clones proven to be gamma/delta-1+ clones had the CD2+ CD3+ CD4(-)-+ CD8(-)-+ TCR delta-1+ beta F1- alpha F1- and delta TCS-1- phenotype, but few clones displayed CD2- or delta TCS-1+ phenotype. These gamma/delta-1+ clones were morphologically large granular lymphocytes, but functionally they did not have NMRC to K562. It is possible to say that TCR gamma/delta clones were rather easily produced from TCR alpha/beta cell-depleted PBMC and effusion cells, and can be used for the study of their nature and characteristics.