Abstract： Objective To study the method for early diagnosis of acute rejection and the role of ELISPOT in donor evaluation. Methods All ventral heterotopic cardiac transplantation models were divided into three groups(each group having 25 recipients)as follows:rejection group(C57BL/6 donor heart to BALB/c recipient,no specific treatment after transplantation),treated group(C57BL/6donor heart to BALB/c recipient, donor specific splenocytes transfusion before transplantation plus 5 μg/g cyclosporin A per day applied continuously from 1 day before operation to 7 day posttransplantation),isograft group(BALB/c donor heart to BALB/c recipient,no specific treatment after transplantation). Mean survival time(MST)and histopathologic changes were observed. By using ELISPOT assay,IFN-γ-secreting splenocytes were detected and counted. Results MST of heart allografts in rejection and treated groups was(7.8±0.77)and(14.80±1.01)days respectively. The survival time of grafts in isograft group was all more than 28 days. There was significant difference among three groups. The number of infiltrating cells in rejection group was much more than the other groups as well as the extent of histopathologic changes. The number of donor-specific IFN-γ-secreting splenocytes in three groups on the posttransplantation day 4 and 7 was(288±16)、(32±10)、(6±2)/2×105and(416±19)、(44±8)、(7±2)/2×105,respectively,which had negative correlation with MST and positive correlation with histopathologic changes. Conclusions The detection of donor-specific IFN-γ-secreting splenocytes with ELISPOT assay might be a useful indicator for early diagnosis of acute rejection.This assay had high sensitivity and specificity enough for pretransplant donor evaluation.