Low IL-1 beta production in leukemic cells from progressive B cell chronic leukemia (B-CLL).

In vitro production of IL-1 beta by cells from 32 patients with benign monoclonal lymphocytosis of undetermined significance (MLUS) and B cell chronic lymphocytic leukemia (B-CLL) was investigated. Normal B lymphocytes (2 x 10(6)) secreted approximately 5 ng/ml of IL-1 beta during 24 h and approximately ten times more after stimulation with Staphylococcus aureus, strain Cowan 1 (SAC). When patients were studied, a loss of IL-1 beta production was found in leukemic cells from progressive disease. Cells from MLUS patients secreted near normal levels of IL-1 beta and responded to SAC stimulation, whereas cells from patients with progressive B-CLL produced no, or little IL-1 beta, and did not respond to SAC. Loss of IL-1 beta production in progressively growing B-CLL may be related to an increased malignant character of these cells. This is discussed in relation to the immunogenicity of the leukemic cells and their capacity to differentiate.