SHARP-2 gene silencing by lentiviral-based short hairpin RNA interference prolonged rat kidney transplant recipients' survival time.

Split- and hairy-related protein-2 (SHARP-2) controls the expression of interleukin-2 (IL-2) and interferon-gamma (IFN-gamma)， which both play a key role in transplant rejection. This study was designed to investigate whether SHARP-2 short hairpin RNA interference (shRNAi) could prolong the survival of rat kidney transplant recipients. A lentiviral-based shRNAi construct， LV-SHARP-2iC， showed a SHARP-2 gene silencing efficiency of 84% in normal rat kidney cells. In activated T-cells， SHARP-2 gene silencing with the LV-SHARP-2iC construct resulted in 61% and 69% down-regulation of IL-2 and IFN-gamma， respectively， compared with a scramble control construct. When donor kidney was perfused with 5 x 10(7) transforming units of the LV-SHARP-2iC construct， the median survival time of the transplant recipients was prolonged by 4 - 5 days compared with control groups. In conclusion， recombinant lentiviral LV-SHARP-2iC construct effectively silenced SHARP-2 gene expression， which reduced IL-2 and IFN-gamma mRNA expression and prolonged rat kidney transplant recipients' survival.