Expression of PTPN22 and SHP-1 in CLL and normal B cells. (A) Cellular extracts from normal PB B cells (PB1, PB2, PB3, PB4, and PB5), normal tonsillar B cells (TB4, TB5, TB6, TB8, and TB9), lymphoma B-cell lines (B104 and BJAB), and CLL B cells were analyzed by immunoblotting with the indicated antibodies. Actin was used as a loading control. (B) Comparison of relative PTPN22 and SHP-1 protein levels in CLL (n = 91 and n = 42, respectively) and normal B cells (n = 14). The BJAB cell line was used as a calibrator. The amount of PTPN22 and SHP-1 in BJAB was arbitrarily set to 1. Mann-Whitney rank-sum test was used to evaluate the significance of differences in PTPN22 and SHP-1 expression between CLL and normal B cells.