Fig. 4

CXCL10 expression is induced along with Tax in JPX-9 cells. a Western blot analysis of Tax expression in JPX-9 cells treated with 10 μM CdCl₂. Cell lysates were prepared from CdCl₂-treated JPX-9 cells at the indicated time points, and Tax expression was confirmed by western blotting with Lt-4 anti-Tax monoclonal antibody. Equal sample loading was verified with anti-α-Tubulin (bottom). Tax protein was almost undetectable in JPX-9 before the induction, but became detectable 6 h after the addition of CdCl₂ to the culture medium. b Induction of CXCL10 mRNA and protein expression in JPX-9 cells treated with CdCl₂. CXCL10 mRNA and protein levels after Tax induction were detected by quantitative real-time PCR and ELISA, respectively. The copy number of CXCL10 mRNA was normalized by the copy number of hypoxanthine guanine phosphoribosyl transferase 1 (HPRT1) mRNA. Quantitative real-time PCR results indicate that CXCL10 mRNA expression was induced along with Tax protein expression in JPX-9 cells (white bars). ELISA data indicated that CXCL10 protein became detectable 12 h after the addition of CdCl₂ to the culture medium, i.e. 6 h after detection of Tax protein and 3 h after detection of CXCL10 mRNA, and the CXCL10 protein levels were still increasing even at 120 h after the addition of CdCl₂ (gray bars). The data are representative of 3 independent experiments. Data shown as mean ± SD, n  =  3