IL-2 production is impaired by C-term AKAP450-GFP overexpression and AKAP450 depletion. (A-B) J77/SEE-pulsed Raji cell conjugates of cells expressing (A) control siRNA (siNeg) or AKAP450 siRNA (siAKAP) and (B) GFP (J77-GFP) or C-term AKAP450-GFP (J77-C-term) were incubated for the times indicated, and a representative Western blot of phospho-Erk1/2 (T202/Y204) is shown. Total Erk1/2 expression was detected as loading control. One of 3 representative experiments is shown. (C-D) IL-2 release was detected by enzyme-linked immunosorbent assay in the culture supernatants of conjugates formed between SEE-pulsed Raji cells and J77 cells transfected with control or AKAP450 siRNA (C) and overexpressing GFPs or C-term AKAP450 GFPs (D). Data from control incubations with unloaded APCs (−SEE). (E-F) Relative surface expression of CD69 in conjugates formed as in panels C and D, detected by flow cytometry. Data are the arithmetic mean ± SD of 3 independent experiments performed in triplicate. *P < .05 (Student t test).