Expression of apoptosis-regulatory proteins in primary CLL B cells and B-cell lines. Immunoblotting analysis was performed with purified CLL B cells from 11 patients, purified normal tonsillar B cells (TB1 and TB2), and the B104, BJAB, and MEC1 cell lines. Actin was used as a loading control. Normalized levels of each protein are expressed as fold change relative to the levels in the MEC1 cell line.