Immunomodulatory effects of xenogenous umbilical cord mesenchymal stem cells on rat heart transplantation / 中国组织工程研究

ABSTRACT

BACKGROUND: Bone marrow mesenchymal stem cells (BMSCs) can prolong the survival time of mice and baboons' alloskin graft and degrade acute and chronic graft-versus-host disease (GVHD) incidence after hematopoietic stem cell transplantation. But, at present there is no report that rat umbilical cord mesenchymal stem cells (UC-MSCs) reduced rejection response following heart transplantation. OBJECTIVE: To study the immunomodulatory effects of rat UC-MSCs on a model of allogeneic heart transplantation. METHODS: A total of 20 DA rats served as donors, and 20 Lewis rats as recipients. They were equally and randomly assigned to 2 groups drug intervention and control groups (n=10). Using double cannulation, the left pulmonary artery and innominate artery of rat donors and external jugular vein and common carotid artery of rat recipients received end-to-end anastomosis under a microscope to establish heterotopic cardiac transplantation. One Wistar pregnant rat was selected to harvest UC-MSCs by collagenase digestion method. Following model establishment, rats in the cell transplantation group received UC-MSCs via caudal vein. Rats in the control group received sodium chloride. Survival time of the transplanted heart was determined. The transplanted heart received histopathology score using the acute rejection diagnosis criteria. Lymphocyte infiltration of transplanted heart was observed using hematoxylin-eosin staining. RESULTS AND CONCLUSION: Compared with the control group, the survival time of the transplanted heart was significantly longer in the cell transplantation group (P = 0.001), and the pathological score of acute rejection was significantly reduced (P = 0.000 4). There were lots of lymphocyte and monocyte infiltration in the myocardium in the control group. Little lymphocyte infiltration was detected in the myocardium in the cell transplantation group, with the presence of mild edema of myocardial interstitial substance. Results verified that rat UC-MSCs can induce immune tolerance of heart transplantation, soften immunological rejection and prolong xenograft survival.