Immune modulation by silencing CD80 and CD86 production in dendritic cells using small hairpin RNA to reduce heart transplant rejection

Abstract

RNA interference (RNAi) plays a potential role in organ transplantation. Small hairpin RNA (shRNA) is an artificial RNA molecule with a tight hairpin turn that can be used to silence the expression of a target gene. We constructed shRNA targeting on the cluster of differentiation 80 (CD80, B7-1) and the cluster of differentiation 86 (CD86, B7-2) and transfected it into dendritic cells (DCs). Fluorescence real-time PCR and flow cytometry confirmed the gene-silencing effect. Interleukin-2 (IL-2) mRNA expression level decreased in T cells that were cocultured with pB7-shRNA-transfected DCs. For in-vivo experiment, we built mice models of abdominal heterotopic heart transplantation and transfused the models with pB7-shRNA-transfected donor-derived DCs. The survival time of the transplanted heart increased; the grade of organ rejection decreased. IL-2 mRNA expression level decreased and it was positively correlated with the grade of organ rejection.

Keywords: Costimulatory pathway; IL-2 mRNA expression; Immune tolerance; Organ transplant rejection; RNA interference.