B cell chronic leukemia more dynamic than previously thought

B cell chronic lymphocytic leukemia (B-CLL) is often thought of as a slowly progressive “disease of accumulation,” but new research indicates that B cell clones are dynamic with significant cell proliferation and death occurring.

The findings, which appear in the Journal of Clinical Investigation for March 1, are based on a study of B cell proliferation in 19 B-CLL patients. The subjects drank deuterated water for 84 days and B cell proliferation was assessed by measuring deuterium incorporation in B cells with gas chromatography/mass spectometry.In contrast to what would be expected from a “disease of accumulation,” the cell populations had “definable and often substantial birth rates,” senior author Dr. Nicholas Chiorazzi, from North Shore-LIJ Research Institute in Manhasset, New York, and colleagues report. The research also found that the B cell birth rate correlated with disease activity and progression. Specifically, patients with a cell birth rate >0.35% per day were more likely than others to have progressive disease.The results indicate that “B-CLL cells proliferate at appreciable rates,” the authors state. “This finding is in conflict with the dogma that B-CLL is a disease characterized almost exclusively by cell accumulation due to a defect in apoptosis.”(Source: J Clin Invest 2005;March 1:000-000: Reuters Health: Oncolink: February 2005.)