Percentage of CD38⁺/CD5⁺/CD19⁺ cells among mutated and unmutated B-CLL cases.

The percentage of CD38-expressing B-CLL cells among 61 patients whose Ig V_H and V_L gene sequences we have determined. Unmutated cases (⧫) display less than 2.0% differences from the most similar germline gene; mutated samples (•) display at least 2% differences. PBMC were analyzed for surface expression of CD19/CD5/CD38 by triple color immunofluorescence using anti-CD19-APC, anti-CD5-FITC, and anti-CD38-PE (all from Becton Dickinson Immunocytometry Systems, San Jose, CA). Isotype-matched negative controls were used in all assays to determine positive from negative results.