Up-regulation of CD23 enhances c-Rel expression. Using established LCLs, whole-cell lysate was analyzed for c-Rel expression by Western blot. Pt1-1wk LCLs were cultured for 1 week and pt1-4wk LCLs, with a lymphoblastic phenotype, were cultured for 4 weeks prior to analysis. C3121 and JY are EBV positive, and Ramos is an EBV-negative B-cell line. Cell surface expression of CD23 (%CD23) was also examined by flow cytometry. Values represent percent positive cells.