Expression of surface membrane markers on B-CLL cells and normal CD5⁺ B cells.

Surface membrane markers underexpressed on B-CLL cells as compared with normal CD5⁺ B cells. PBMCs from B-CLL patients and age-matched healthy donors were analyzed for marker expression on CD5⁺CD19⁺ cells. (A) Representative flow cytometric profiles of expression of these markers on B cells from a 67-year-old healthy donor (N39) and CLL 308. (B) Paired bars depict the mean ± SE of the percentage of CD5⁺CD19⁺ cells expressing these markers in 51 IgM⁺ and 10 IgG⁺ B-CLL patients and 20 age-matched healthy controls. B-CLL cells expressed significantly lower percentages (P < .0001) of CD40, CD72, CD22, CD79b, CD62L, CD38, FcγRIIb, CD40L, CD95, and CD80 than normal CD5⁺CD19⁺ cells. The expression of these markers was variable both in the patients and in the markers, with the greatest variability seen for CD38. The SE and the SD for these markers ranged from 1.2 to 4.7 and from 8.9 to 35.5, respectively.