Human T-cell hybrids secreting lymphokines: effect of different parent cell clones of the human T-cell acute lymphoblastoid leukaemia line CCRF-CEM.

We have cloned a number of cell lines from the human T-lymphocyte acute lymphoblastoid leukaemia (ALL) line CCFR-CEM, and attempted to construct functionally active human T-lymphocyte hybrids with them. Functional hybrids were generated using only one particular clone, 3H6. The activities found in the supernatants of two of these hybrids, DB1G7 and DB2D10, are described. Supernatant from DB1G7 was found to suppress strongly the migration of normal human peripheral blood mononuclear cells, while that from DB2D10 was shown to inhibit the proliferative response of human T lymphocytes to both phytohaemagglutinin and concanavalin A. There was no cross-reactivity between the two supernatants, confirming the usefulness of the human T-lymphocyte hybrid technique in dissecting human T-lymphocyte function. The successful use of 3H6 is contrasted with the failure of another clone, 2H2, to permit the production of functional hybrids. Problems relating to the use of CCRF-CEM and its clones as parent cell lines in the production of human T-lymphocyte hybrids are discussed.