Objective: To observe the effects of chemokines CXCL9 and CXCL10 on cardiac allograft acute rejection mediated by alloreactive memory T cells in a retransplantation model.
Methods: Heart transplantation was performed 6 weeks after skin grafting. The mice were divided into 3 groups of control (direct heterotopic heart transplantation without skin grafting); experimental (heart transplantation after skin grafting) and syngraft (C57BL/6→C57BL/6, heterotopic heart transplantation) (n = 12 each). Graft survival and the pathological changes of cardiac graft were observed. And related gene expression in cardiac grafts and serum concentration of CXCL9/CXCL10 were detected.
Results: The mean survival time of control and experimental groups was 7.75 and 3.25 days respectively (P < 0.01).Serum concentrations of CXCL9 and CXCL10 in recipient mice were higher in the experimental group than those in the control group. Compared with the control group, the relative gene expressions of CXCL9 and CXCL10 were higher in the experimental group. According to pathological examinations, the histological rank of cardiac allograft was Grade 2.27 ± 0.25 in the control group versus Grade 4.12 ± 0.03 in the experimental group (P < 0.01).
Conclusions: CXCL9 and CXCL10 play critical roles in retransplantation mediated by alloreactive memory T cells. And acute rejection of cardiac allograft is more extensive in retransplantation.