BACKGROUND: The cold ischemic time may be more prolonged for facial tissue allografts than for organ allografts. Previous researches have shown that prolonged ischemia resulted in increased signs of rejection in a rat groin allotransplantation model; however, the relationship between cold ischemia and alloantigen-induced rejection was unclear. MATERIALS AND METHODS: Vascularized groin flaps were transplanted from BN to Lewis rats after 0, 6, 12, 18, or 24 h of storage at 4 °C, and the allografts in each group were evaluated daily. Biopsy samples taken from the allo-0 h and allo-24 h groups on postoperative d 2-8 were graded for signs of acute rejection. Biopsy samples taken from the allo-0 h and allo-24 h groups on postoperative d 5 were stained for chemokine receptor CXCR3. RESULTS: When the cold ischemia time was greater than 18 h, the survival time of the grafts was significantly shorter (6.2 ± 1.3 d) than that of the grafts that did not undergo cold ischemia (9.0 ± 1.2 d). Histological valuation showed acceleration of activated lymphocyte infiltration in the allo-24 h group (2.2 ± 0.4 d) compared with the allo-0 h group (4.8 ± 0.4 d). Furthermore, the proportion of CXCR3-positive cells in the allo-24 h group (49.7% ± 6.0%) was significantly higher than that in the allo-0 h group (22.9% ± 3.4%) on d 5 after transplantation. CONCLUSIONS: Prolonged ischemia has a deleterious effect on allograft survival, and the chemokine receptor CXCR3 may play a role in this process.
BACKGROUND: The cold ischemic time may be more prolonged for facial tissue allografts than for organ allografts. Previous researches have shown that prolonged ischemia resulted in increased signs of rejection in a rat groin allotransplantation model; however, the relationship between cold ischemia and alloantigen-induced rejection was unclear. MATERIALS AND METHODS: Vascularized groin flaps were transplanted from BN to Lewis rats after 0, 6, 12, 18, or 24 h of storage at 4 °C, and the allografts in each group were evaluated daily. Biopsy samples taken from the allo-0 h and allo-24 h groups on postoperative d 2-8 were graded for signs of acute rejection. Biopsy samples taken from the allo-0 h and allo-24 h groups on postoperative d 5 were stained for chemokine receptor CXCR3. RESULTS: When the cold ischemia time was greater than 18 h, the survival time of the grafts was significantly shorter (6.2 ± 1.3 d) than that of the grafts that did not undergo cold ischemia (9.0 ± 1.2 d). Histological valuation showed acceleration of activated lymphocyte infiltration in the allo-24 h group (2.2 ± 0.4 d) compared with the allo-0 h group (4.8 ± 0.4 d). Furthermore, the proportion of CXCR3-positive cells in the allo-24 h group (49.7% ± 6.0%) was significantly higher than that in the allo-0 h group (22.9% ± 3.4%) on d 5 after transplantation. CONCLUSIONS: Prolonged ischemia has a deleterious effect on allograft survival, and the chemokine receptor CXCR3 may play a role in this process.