Immunogene Attenuates Hepatic Fibrosis With Vaccine Based On Xenogeneic CD40 Ligand

Backgroud & Aims: Hepatic fibrosis is a characteristic feature of chronic liver diseases, such as autoimmune disease, hepatic B or C virus infection. In these diseases, activated T cells and cytokines are important direct or indirect causes in initiating the fibrotic process. CD40-CD154 interactions is critical for priming T cells and producing cytokines. Disruption of the CD40-CD154 pathway can reduce inflammation and autoimmune diseases. We explored this idea by using xenogenic homologous CD 154 gene vaccine to blockade the CD154 signaling and to prevent the hepatic fibrosis which induced by repeatedly injection of concanavalin A (Con A). Methods: To assay the expressional ability of these plasmids, transfected its to COS-1 cells and identified by Western blot and RT-PCR in vitro. Repeated Con A challenge in mice induces liver fibrosis. Simultaneously, mice immunized with xenogeneic (human) CD 154 (pORF-hCD154, p-hCD154) or corresponding control mouse CD 154 (pORF-mCD154, p-mCD154) andempty vector (pORF-mcs, p-c). After 24 h of each injection of Con A, the serum obtained from mouse and assayed the injury of hepatocytes and levels of cytokines in the serum. One week after sixth Con A injected, indices of fibrosis were assessed. We measured hepatic fibrosis (Masson Trichrome-stained and liver stained), HSCs marker (expression a-smooth muscle actin) and serum levels of cytokines were measured. Autoantibodies against CD 154 were identified by Westen blot analysis and ELISA assay. Results: Mice immunized with p-hCD154 markedly attenuated an increase of enzyme activity, HSC activation, levels of INF-yD IL-2, IL4, and IL-10, and hepatic fibrosis without apparent systemic or local side effects. Adoptive transfer of the purified Igs could decrease injury of hepatocytes. Anti-CD 154 antibodies producing B cells dected by ELISPOT. Conclusions: These findings may provide a new vaccine strategy for treatment of liver fibrosis induced by Con A through the induction of the autoimmune response against CD 154 in a cross-reaction between the xenogenic homologous and self CD 154. It maybe importance in the further exploration of the applications of other xenogeneic homologous molecules identified in human and other animal genome sequence projects in autoimmune diseases therapy.