CD38 and B-cell chronic lymphocytic leukemia: Immunophenotyic analysis of proliferating CLL cells at day 6 after ex vivo stimulation showed a lower expression of CD5, an upregulation of CD138 but not of CD38 and no IgG expression on cell surface, as compared to the expression at day 0 before stimulation (Fig. S3B) which underlined the biological relevance of this model of ex vivo stimulation.