Objectives: The mouse kidney transplantation model presents challenges in terms of surgical difficulty and low success rate, making it difficult to master. This study aims to provide a crucial model for transplantation immunology research by modifying and developing novel techniques for mouse kidney transplantation.
Methods: A total of 57 pairs of mice were used to establish and compare the modified and innovative surgical techniques for mouse kidney transplantation. Three different surgical models were established, including the abdominal suture technique for orthotopic kidney transplantation, the abdominal cuff technique for orthotopic kidney transplantation, and the cervical cuff technique for ectopic kidney transplantation. BALB/c or C57BL/6 male mice, aged 8 to 12 weeks and weighed 20 to 25 g with specified pathogen free-grade were served as the donor mice or the recipient mice. The surgical technique characteristics, key surgical times, complications, and pathological examination in the early postoperative period were summarized and compared.
Results: Three different surgical models of mouse kidney transplantation were successfully established. The comparison of warm ischemic time for the 3 groups of mice showed no statistical significance (P=0.510 4). The abdominal suture group had the shortest total operation time of the donor compared with the abdominal cuff group and the cervical cuff group [(18.3±3.6) min vs (26.2±4.7) min and (22.8±2.5) min; both P<0.000 1]. There was a significant difference in cold ischemia time among the 3 groups (all P<0.000 1), with (60.8±4.1) min in the cervical cuff group, (43.3±5.0) min in the abdominal suture group, and (88.8±6.7) min in the abdominal cuff group. Due to different anastomosis methods, the cervical cuff group had the shortest time [(17.6±2.7) min], whereas the abdominal cuff group had the longest time [(38.8±5.4) min]. The total operation time for the recipients showed significant differences (P<0.000 1), with the abdominal suture group having the shortest time [(44.0±6.9) min], followed by the cervical cuff group [(64.1±5.2) min], and the abdominal cuff group [(80.0±6.0) min] being the longest. In the 32 mice of the abdominal suture group, there were 6 with intraoperative bleeding, including 1 arterial intimal injury bleeding and 5 with bleeding after vessel opening. Six mice had ureteral complications, including ureteral bladder anastomotic stenosis, necrosis, and renal pelvis dilation. Two mice had postoperative abdominal infections. In the abdominal cuff group, there was no intraoperative bleeding, but 6 mice showed mild arterial stenosis and 5 showed venous stenosis, 4 arterial injury, 4 arterial thrombosis, and 2 ureteral complications. No postoperative infections occurred in the mice. In the cervical cuff group, no intraoperative bleeding, arterial intimal injury, arterial/venous stenosis, or thrombosis were found in 13 mice. Five mice had ureteral complications, including ureteral necrosis and infection, which were the main complications in the cervical cuff group. The renal function in mice of the 3 groups remained stable 7 days after surgery. Hematoxylin and eosin staining and periodic acid-Schiff staining showed no significant differences in terms of acute rejection among the 3 surgical methods (all P>0.05).
Conclusions: All 3 surgical methods are able to successfully establish mouse kidney transplantation models, with no significant differences observed in the short-term graft survival and acute rejection. The modified abdominal suture technique and abdominal cuff technique have their respective advantages in research applications. The novel cervical cuff technique for ectopic kidney transplantation model is relatively simple to be prepared and causes less trauma to the mice, providing more options for studies involving xenotransplantation, secondary transplantation, and local lymphatic drainage. However, the difficulty in harvesting the donor kidney and the high incidence of ureteral infections need further validation in long-term survival. This study holds important reference value for choosing the type of mouse kidney transplantation model for different research needs.
目的: 小鼠肾移植模型手术难度大，成功率低，难以掌握，本研究拟改良并探索新型小鼠肾移植模型，为移植免疫基础研究提供借鉴。方法: 分别建立小鼠腹部缝合法原位肾移植模型、腹部套管法原位肾移植模型和颈部套管法异位肾移植模型共57对供受体。供受体采用BALB/c小鼠或C57BL/6小鼠；供受体均选用8~12周龄、体重20~25 g的雄性无特定病原级小鼠。总结和比较3种模型的技术特点和手术时间、并发症、病理学检查等术后早期指标。结果: 成功建立3种不同手术方式的小鼠肾移植模型。3组小鼠供肾热缺血时间比较差异无统计学意义(P=0.510 4)，腹部缝合组的供体手术总时间与腹部套管组和颈部套管组比较最短[(18.3±3.6) min vs (26.2±4.7) min和(22.8±2.5) min；均P<0.000 1]。冷缺血时间比较3组差异有统计学意义(P<0.000 1)，腹部套管组、颈部套管组及腹部缝合组分别为(88.8±6.7)、(60.8±4.1)及(43.3±5.0) min。受体由于吻合方式不同，颈部套管用时最短[(17.6±2.7) min]，腹部套管用时最长[(38.8±5.4) min]。受体的总手术时间比较差异有统计学意义(P<0.000 1)，腹部缝合组、颈部套管组及腹部套管组分别为(44.0±6.9)、(64.1±5.2)及(80.0±6.0) min。在并发症发生方面，32只腹部缝合组中6只发生术中出血，其中1只因为动脉内膜损伤出血，5只为血管开放后出血；6只小鼠发生输尿管并发症，包括输尿管膀胱吻合口狭窄、坏死以及肾盂积水；2只小鼠术后发生腹腔感染。腹部套管组未发生术中出血，但6只出现动脉轻度狭窄，5只静脉狭窄，4只动脉损伤，4只动脉血栓，2只输尿管并发症，没有小鼠在术后发生感染。在颈部套管组中，13只小鼠均未发生术中出血、动脉内膜损伤、动脉/静脉狭窄以及血栓，5只发生输尿管并发症，包括输尿管坏死和感染，是颈部套管组最主要的并发症。3组小鼠在移植后7 d肾功能保持稳定；苏木精-伊红和过碘酸希夫染色显示3种手术方式的移植物在急性排斥反应方面差异均无统计学意义(均P>0.05)。结论: 3种术式均能成功建立小鼠肾移植模型，在近期移植物生存期和排斥反应方面未见明显差别。改良后的腹部缝合法以及腹部套管法在研究应用中各有优势，首创的小鼠颈部套管法异位肾移植模型的制备相对简单、小鼠创伤较小，可为异种移植、二次移植及局部淋巴引流探索等研究提供更多选择，但供肾摘取难度大，输尿管感染发生率高，远期存活还需更多模型验证。本研究为不同研究需求下选择小鼠肾移植模型的类型提供了重要借鉴意义。.
目的: 小鼠肾移植模型手术难度大，成功率低，难以掌握，本研究拟改良并探索新型小鼠肾移植模型，为移植免疫基础研究提供借鉴。
方法: 分别建立小鼠腹部缝合法原位肾移植模型、腹部套管法原位肾移植模型和颈部套管法异位肾移植模型共57对供受体。供受体采用BALB/c小鼠或C57BL/6小鼠；供受体均选用8~12周龄、体重20~25 g的雄性无特定病原级小鼠。总结和比较3种模型的技术特点和手术时间、并发症、病理学检查等术后早期指标。
结果: 成功建立3种不同手术方式的小鼠肾移植模型。3组小鼠供肾热缺血时间比较差异无统计学意义(P=0.510 4)，腹部缝合组的供体手术总时间与腹部套管组和颈部套管组比较最短[(18.3±3.6) min vs (26.2±4.7) min和(22.8±2.5) min；均P<0.000 1]。冷缺血时间比较3组差异有统计学意义(P<0.000 1)，腹部套管组、颈部套管组及腹部缝合组分别为(88.8±6.7)、(60.8±4.1)及(43.3±5.0) min。受体由于吻合方式不同，颈部套管用时最短[(17.6±2.7) min]，腹部套管用时最长[(38.8±5.4) min]。受体的总手术时间比较差异有统计学意义(P<0.000 1)，腹部缝合组、颈部套管组及腹部套管组分别为(44.0±6.9)、(64.1±5.2)及(80.0±6.0) min。在并发症发生方面，32只腹部缝合组中6只发生术中出血，其中1只因为动脉内膜损伤出血，5只为血管开放后出血；6只小鼠发生输尿管并发症，包括输尿管膀胱吻合口狭窄、坏死以及肾盂积水；2只小鼠术后发生腹腔感染。腹部套管组未发生术中出血，但6只出现动脉轻度狭窄，5只静脉狭窄，4只动脉损伤，4只动脉血栓，2只输尿管并发症，没有小鼠在术后发生感染。在颈部套管组中，13只小鼠均未发生术中出血、动脉内膜损伤、动脉/静脉狭窄以及血栓，5只发生输尿管并发症，包括输尿管坏死和感染，是颈部套管组最主要的并发症。3组小鼠在移植后7 d肾功能保持稳定；苏木精-伊红和过碘酸希夫染色显示3种手术方式的移植物在急性排斥反应方面差异均无统计学意义(均P>0.05)。
结论: 3种术式均能成功建立小鼠肾移植模型，在近期移植物生存期和排斥反应方面未见明显差别。改良后的腹部缝合法以及腹部套管法在研究应用中各有优势，首创的小鼠颈部套管法异位肾移植模型的制备相对简单、小鼠创伤较小，可为异种移植、二次移植及局部淋巴引流探索等研究提供更多选择，但供肾摘取难度大，输尿管感染发生率高，远期存活还需更多模型验证。本研究为不同研究需求下选择小鼠肾移植模型的类型提供了重要借鉴意义。
Keywords: cuff technique; kidney transplantation; mouse; suture technique.