Abstract: Objective To study the basic expression of the interferon-inducible protein p204 in rat aortic vascular adventitial fibroblasts (VAFs), and the effect of interferon alpha (IFNα) on VAF proliferation and p204 expression. Methods Using immunohistochemistry and immunocytochemistry to observe the expression and distribution of protein p204, using RT-PCR and Western blot to detect the expression of induced p204 mRNA or protein. After treated with different concentrations of IFNα, the cell proliferation of the VAF was observed by MTT assay and the corresponding p204 expression was detected by Western blot. Results p204 stain was positive on rat aortic adventitia, p204 was present in the cytoplasm and also nucleus of VAF, but its expression was more obvious in the nucleus. IFNα (the terminal concentration of 1×106 IU/L) stimulating VAF more than 6 hours was enough to induce Ifi204 mRNA significant expression, and more than 24 hours for enough expression of protein p204. IFNα inhibited cell proliferation of VAF was dose dependence, followed by p204 expression increased correspondingly (P < 0.05). Conclusion There is basic expression of p204 in rat aortic VAF, p204 expression is not limited to the nucleus and IFNα can easily induce the gene and protein of p204 expression up-regulated in VAF; IFNα inhibits VAF proliferation may partly relate to the increased p204 expression.

Key words: Interferon, Interferon induced protein, p204, Fibroblast, Proliferation