Detection of acute renal allograft rejection by analysis of renal tissue proteomics in rat models of renal transplantation.

At present, the diagnosis of renal allograft rejection requires a renal biopsy. Clinical management of renal transplant patients would be improved if rapid, noninvasive and reliable biomarkers of rejection were available. This study is designed to determine whether such protein biomarkers can be found in renal-graft tissue proteomic approach. Orthotopic kidney transplantations were performed using Fisher (F344) or Lewis rats as donors and Lewis rats as recipients. Hence, there were two groups of renal transplant models: one is allograft (from F344 to Lewis rats); another is syngrafts (from Lewis to Lewis rats) serving as control. Renal tissues were collected 3, 7 and 14 days after transplantation. As many as 18 samples were analyzed by 2-D Electrophoresis and mass spectrometry (MALDI-TOF-TOF-MS). Eleven differentially expressed proteins were identified between groups. In conclusion, proteomic technology can detect renal tissue proteins associated with acute renal allograft rejection. Identification of these proteins as diagnostic markers for rejection in patients' urine or sera may be useful and non-invasive, and these proteins might serve as novel therapeutic targets that also help to improve the understanding of mechanism of renal rejection.