Gene therapy for induction of immunological tolerance in organ allografts

（背景）基因转移方法有可能将免疫抑制分子直接引入同种异体移植物，从而限制常规免疫抑制治疗对受体的全身副作用。（目的）分析腺病毒介导的il - 4基因在大鼠肾移植模型中的作用及其可能的机制。（材料与方法）用Adex1CAmIL4或AxCALacZ（分别为RIKEN DNA Bank）原位灌注肾同种异体移植物（BN大鼠），在4C下孵育1.5、24、48、72小时（离体），或/并移植到LEW受体。用4C生理盐水或UW溶液灌注腺病毒载体，移植肾在4C生理盐水（1.5h）或UW溶液（24-72h）中保存。(结果)1。体外模型保存24h后检测到β-gal，保存1.5h后检测不到β-gal。移植后，移植肾在第2天/第7天无β-gal染色。2. 在离体保存中，在Adex1CAmIL4灌注的所有移植肾（1.5h-72h）中均有IL4的表达，而在冷生理盐水灌注的对照组中，在任何保存期均未检测到IL4的表达。3. 与移植后第7天保存1.5h的同种异体肾移植相比，Adex1CAmIL4基因移植后维持24h的同种异体肾移植的组织学损伤明显减轻。（结论）与腺病毒介导的il - 4基因治疗相比，保存24h更能诱导免疫抑制作用。维持1.5小时。il - 4的适当表达在移植后早期（0-2天）可能是重要的。在移植环境下基因转移的“最佳途径”有待进一步研究。

(Background) Gene transfer approach has the potential to introduce immunosuppressive molecules directly into the allograft, which in turn should limit systemic side effects of conventional immunosuppressive therapy to recipients. (Aim) To analyze the efficacy and putative mechanisms of adenoviral-mediated IL4 gene transfer in rat kidney transplant model. (Material ＆ Method) Renal allografts (BN rat) were perfused in-situ with Adex1CAmIL4 or AxCALacZ (RIKEN DNA Bank, respectively) incubated at 4C for 1.5, 24, 48, 72h (ex-vivo), or/and transplanted to LEW recipients. Adenovirus vector was perfused with 4C saline or UW solution, and renal grafts were preserved in 4C saline (1.5h) or UW solution (24-72h). (Results) 1. β-gal was detected after 24h preservation, but not 1.5h in ex-vivo model. After transplantation, there was mo staining of β-gal in renal allograft at day2/day7. 2. In ex-vivo preservation, IL4 was expressed in all of renal grafts (1.5h-72h) with Adex1CAmIL4 perfusion, even though it was not detected in control group perfused with cold saline in any preserved term. 3. Histological damage of renal allografts maintained for 24h after Adex1CAmIL4 gene transfer were diminished as compared with 1.5h preserved grafts at day7 after transplantation. (Conclusion) 24h preservation was prefer to induce immunosuppressive effects of Adenovirus-mediated IL4 gene therapy as compared. with 1.5h maintaining. It seems that appropriate expression of IL4 might be important at the early phase (day0-2) after transplantation. Further study will be necessary to inquire "optimal way" of gene transfer in transplant setting.