Transduction of ZAP-70− CLL cells with Ad-ZAP-70 versus Ad-ZAP-70-YF292 and measurement of anti-μ–induced increases in phosphorylated p72Syk, BLNK, or PLC-γ. (A) Immunoblot ana-lysis for ZAP-70 (top row) in lysates of CLL cells before or after transduction with Ad-ZAP-70 or Ad-ZAP-70-YF,292 as indicated at the top of each lane. The blots were stripped and then reprobed with anti–β-actin to monitor for protein loading (bottom row), as indicated on the left of each blot. (B-D) Anti-μ–induced percentage increases in phosphorylated p72Syk (B), BLNK (C), or PLC-γ (D) detected in ZAP-70− CLL B cells that were transduced with the control vector or Ad-ZAP-70-YF292 (left panel) or with Ad-ZAP-70 or Ad-ZAP-70-YF292 (right panel). Each symbol represents the percentage increase in phosphorylated protein detected in an individual CLL cell sample. The lines connect the percentage increase in detected phosphorylated protein of anti-μ–treated CLL cells of the same sample transduced with each of the different vectors. The differences in the mean percentage increase of phosphorylated protein upon anti-μ treatment in control vector–transduced CLL cells versus that of Ad-ZAP-70-YF292–transduced CLL cells was significant (P < .05). However, there was not a significant difference in the mean percentage increase of phosphorylated protein upon anti-μ treatment of Ad-ZAP-70–transduced CLL cells versus that of Ad-ZAP-70-YF292–transduced CLL cells.