Cultured T cells from patients with T cell chronic lymphocytic leukemia demonstrate a normal phenotype

Peripheral blood mononuclear cells from eight patients with the rare T-cell form of chronic lymphocytic leukemia were isolated and cultured with Interleukin-2 (IL-2). In all but one case, cultured T-cells (CTC) were established. Various culture conditions were tested for their effectiveness; feeder layers proved valuable for expanding the cultures to large volumes. The CTC remained IL-2 dependent. Analysis of surface determinants on these CTC showed a polyclonal proliferation of T-cells. The distribution of subset markers in the patients' CTC population had completely changed in comparison to the "fresh" peripheral blood cell population but was similar to CTC initiated from healthy donors. Our data suggest that the patients' few contaminating normal T-lymphocytes expanded in culture, while the malignant cells were unresponsive to IL-2. This conclusion is supported by growth characteristics and morphology of the CTC.