Expression of tartrate-resistant acid phosphatase in B-CLL treated with phorbol ester or phorbol ester plus calcium ionophore.
Cells from 3 patients with B-chronic lymphocytic leukaemia (B-CLL) and 1 with B-prolymphocytic leukaemia (B-PLL) were treated in vitro with the phorbol ester 12-0-tetradecanoylphorbol (TPA), the calcium ionophore A23187, or a combination of TPA and A23187. TPA induced the cells to adhere to the culture flask or to clump in dense clusters; single cells became enlarged, often with cytoplasmic elongations. Cells treated with TPA plus A23187 acquired a plasmacytoid morphology and formed regular aggregates in culture. Only TPA alone induced the expression of tartrate-resistant acid phosphatase (TRAP) as documented by isoelectric focusing on horizontal thin-layer gels. The TRAP isoenzyme was first detected after 24 h of TPA treatment; its intensity increased during further TPA exposure, being maximally expressed at 72/96 h. The results suggest that, while TPA triggers B-CLL cells to convert to hairy cell leukaemia (HCL)-type cells, the double stimulus which more closely imitates physiological activation initiates a 'normal' differentiation programme which leads to plasma cells.
D000135:Acid Phosphatase / Q000378:metabolism*; D000368:Aged; D001402:B-Lymphocytes / Q000187:drug effects / Q000201:enzymology*; D000001:Calcimycin; D004357:Drug Synergism; D005260:Female; D006801:Humans; D007527:Isoenzymes / Q000378:metabolism; D015451:Leukemia, Lymphocytic, Chronic, B-Cell / Q000201:enzymology*; D015463:Leukemia, Prolymphocytic / Q000201:enzymology; D008297:Male; D008875:Middle Aged; D013644:Tartrates; D013755:Tetradecanoylphorbol Acetate
D007527:Isoenzymes; D013644:Tartrates; D000001:Calcimycin; D000135:Acid Phosphatase; D013755:Tetradecanoylphorbol Acetate