RESUMO
BACKGROUND: Some reports suggest mesenchymal stem cells (MSCs) have immunosuppressive properties. However, conflicting evidence regarding the role of MSCs has emerged. OBJECTIVES: To gain a better understanding of the immunosuppressive properties of mesenchymal stem cells (MSCs) in a rat heart transplantation model. MATERIAL AND METHODS: MSCs were obtained from the femoral and tibial bone marrow of Sprague-Dawley rats and cultured. Heart-transplanted rats were allocated into a MSC-treated group and 2 control groups. On postoperative day 7, 1 rat was sacrificed and the pathological changes of heart tissues were assessed. Serum proteomic spectra were generated by surface-enhanced laser desorption/ionization-time-of-flight mass spectrometry (SELDI-TOF-MS). RESULTS: Rat MSCs displayed the typical spindle-shaped morphology in culture and significantly prolonged the graft survival up to 33.25 ± 2.54 days compared with controls (19.75 ± 1.56 and 11.16 ± 1.34 days, respectively). Pathological analysis showed the inflammatory cell infiltration in the MSC-treated group was significantly reduced. SELDI analysis showed that 5 protein/peptide peaks with M/Z 1272.33, 1986.65, 2323.42, 5375.59 and 12968.11 were up-regulated in the MSC-treated group (P < 0.001). CONCLUSIONS: Donor-derived MSCs clearly alleviate acute rejection following heart transplantation in rats and significantly prolong the isograft survival time.
