CXCR3 agonists stimulate activation of Akt in CXCR3-transfected COS-7 cells. (A) COS-7 cells transiently transfected with CXCR3 (2.0 μg plasmid/10⁶ cells) were stimulated for different periods of time with 10 (Ai), 30 (Aii), and 100 (Aiii) nM CXCL11, and phosphorylation of Akt was determined by Western blot analysis using specific anti–phosho-Akt (P-Akt) antibodies. Phosphorylation was quantified by chemiluminescence and corrected for total Akt (T-Akt) expression on stripped blots. (B) CXCR3-expressing COS-7 cells were incubated with 30 nM CXCL11 or CXCL10 for 15 minutes before lysing the cells. (C-D) Involvement of G_i- (C) and PI3K–signaling pathway (D) in CXCL11-induced Akt phosphorylation. CXCR3-expressing COS-7 cells were grown in serum-free medium in the presence of PTX (100 ng/mL, 48 h; C) or wortmannin (wort) (100 nM, 30 minutes; D) and exposed to CXCL11 (15 minutes, 30 nM) before lysis and Western blot analysis. A representative experiment of at least 2 independent experiments is shown.