A method for assessing risk of losing a transplanted organ by a patient having an episode of acute rejection of the transplanted organ is described. The method includes obtaining from the patient a cell sample from the transplanted organ or peripheral blood, determining a level of FOXP3 in the cell sample, and correlating the level with the risk of loss of the transplanted organ, wherein, compared to a control level, a significantly greater level of FOXP3 in the cell sample from the transplanted organ or a significantly lower level of FOXP3 in the cell sample from the peripheral blood correlates with a decreased risk of loss of the transplanted organ.