OBJECTIVETo investigate the role of the dynamic process of peripheral blood CD68 mononuclear cells proportion and macrophages inflitration and possible correlation between them during acute rejection of rat oral mucosal xenotransplantation.

METHODSThirty-six female wistar rats were divided into three groups randomly, including xenotransplantation group (n = 15), trauma control group (n = 12) and normal control group (n = 9). The rat oral mucosa xenotransplantation model was established. The flow cytometry was used to evaluate the peripheral blood CD68 mononuclear cell and immunohistochemical assay performed to detect the macrophages infiltration one week (W1), two weeks (W2) and four weeks (W4) after xenotransplantation.

RESULTSThe peripheral blood CD68 mononuclear cells percentage of each xenotransplantation group presented a rise and fall tendency at the three time points, and the peak value appeared at W4 (43.1%), and the nadir at W2 (10.4%). The macrophage counts achieved peak value in xenotransplantation group at W1 [580.0(195.5) cell/high power field], and then reduced with time.

CONCLUSIONSThe mononuclear cells and macrophage were capable of recognizing the xenograft and directly participated the acute rejection of rat oral mucosal xenotransplantation. The peripheral blood mononuclear cells percentage could reflect macrophage infiltrating condition at the early stage of the acute rejection.