Flow cytometric detection of CD34 antigen and bcl-2 protein coexpression in isolated and cultured CLRPP.

Isolated CLRPP (upper cytogram) were cultured in serum-free conditions (see Materials and methods for details) in the absence (lower left cytogram) or in the presence (10 μg/mL; lower right cytogram) of an anti-TGF-β1 neutralizing mAb. Numbers indicate the percentage of double-positive CLRPP and in parentheses the mean bcl-2 fluorescence channel is shown for each experimental condition. Parallel cultures in the presence of irrelevant isotype-matched mouse immunoglobulins showed comparable results to those observed in control CLRPP cultures.P < .0001 comparing the number of bcl-2+ cells in the presence and the absence of anti-TGF-β1 mAb.