PCI-32765 antagonizes microenvironment stimuli. (A) CD19⁺ cells from CLL patients (N = 10) were incubated with or without 10μM PCI-32765 and 1 μg/mL CD40L or 50 ng/mL BAFF for 48 hours. (B) CD19⁺ cells from CLL patients (N = 5-10) were incubated with or without 10μM PCI-32765 and 20 ng/mL TNF-α, 40 ng/mL IL-6 or 800 U/mL IL-4 for 48 hours. (C) CD19⁺ cells from CLL patients (N = 7) were incubated with or without 10μM PCI-32765 on and off fibronectin coated plates for 48 hours. (D) CD19⁺ cells from CLL patients (N = 8) were isolated from peripheral blood and incubated with or without various concentration of PCI-32765 (0.1μM-10μM) in suspension or on an Hs5 cell layer for 48 hours. (A-D) Viability was determined by annexin-V/PI flow cytometry, and is shown relative to time-matched untreated controls for each group. Dark lines represent averages.