Indirect stimulation of B-cell proliferation in vitro by T cells, as evidenced by cytogenetic analysis of PHA-stimulated cell cultures of B-cell lymphomas.

In a retrospective study of non-Hodgkin's lymphomas, the 14q+ marker was found in at least one of the samples examined from 17 patients with B-cell lymphoproliferative diseases (LPD). In the PHA-stimulated cultures, the marker was found in each sample in 10%-100% of the cells. An indirect stimulation, as indicated by a 3H-thymidine incorporation and IG secretion, of normal B cells by a T-cell mitogen, such as PHA, has been recently documented. This phenomenon is confirmed by our chromosome analysis, which demonstrated characteristic chromosome changes in PHA-stimulated cultures of patients with B-cell malignancies and indicated that the phenomenon can be observed not only in normal B cells but also in malignant B cells.