犬头面部复合组织同种异体移植模型的建立

目的建立犬头面部复合组织同种异体移植的实验动物模型。方法①解剖研究：用4只杂种犬进行头面颈部的解剖及复合组织瓣的切取研究。②自体回植（Ⅰ组n=5）：为选择最佳的复合组织瓣移植方式，进行了三种形式的复合组织瓣白体回植。③异体移植（Ⅱ组n=6）：以第三种复合组织瓣及其改良的组织瓣形式进行了两种头面部复合组织异体移植。免疫抑制治疗方案为环孢霉素A和皮质激素联合应用，依据环孢霉素A血药浓度调整用药剂量。分别在术后4、6、12周及6个月对眼轮匝肌进行肌电图检测。结果①犬头面部的解剖特征与人相似，以颈外动静脉为血管蒂能够为头面部复合组织瓣提供良好的血供。②IC组两只犬长期存活，但出现唾液漏。③Ⅱa组中1只犬于移植术后28d免疫排斥，通过调整环孢霉素A及强的松的用量并局部应用氯倍他索涂抹，2周后治愈，现已存活309d。Ⅱb组中3只犬现已分别存活159、129和108d，无并发症，肌电图显示眼轮匝肌功能逐步恢复。结论改良犬单侧上半头面部组织瓣异体移植模型是研究头面部复合组织异体移植的理想模型。     

同种异体复合组织移植的免疫治疗进展

同种异体复合组织移植是现今修复再造领域的一种新选择,但术后的免疫排斥是公认的医学难题.近年来由于复合组织移植数量的增多,使术后的免疫抑制方案成为新热点,本文介绍并总结了同种异体复合组织移植后免疫抑制治疗的进展及应用.     

兔同种异体颜面复合组织移植后面神经再生的初步研究

目的 建立兔颜面部复合组织同种异体移植的实验动物模型,观察移植后面神经的再生情况.方法 选取日本大耳白兔16只,随机配对后分别作为供、受体,分为8对.建立兔同种异体颜面复合组织移植的实验动物模型,FK506与皮质激素联合应用作为免疫抑制治疗方案.术后14、28、40d取移植面神经吻合口处标本分别行HE染色光镜和透射电镜观察,术后28、40d分别行神经肌电图检测,分析移植后兔面神经的再生情况.结果 8例移植手术中,6例获得成功.移植后14d神经纤维以变性改变为主,有少量神经纤维长入吻合口,28d移植神经的吻合口有较多的神经纤维长入,神经束排列较前规则,40d再生神经纤维变得较前成熟,有髓神经的数量增多,但仍可见到变性的神经纤维.术后28d未测得明显的神经动作电位,40d测得的神经动作电位波形离散,表现为明显的传导阻滞.结论 同种异体颜面复合组织移植后面神经的再生是个极为缓慢的过程,需要经历一系列的病理生理过程.移植后40d神经吻合口可出现组织结构上较为成熟的再生神经纤维,但要达到功能上的恢复尚需更长时间.     

专题讨论：异体复合组织移植局部免疫抑制的病例分析

与内脏器官移植相比,异体复合组织移植(CTAs)包含了许多组织,如全部或部分的皮肤、皮下组织、结缔组织、肌肉、骨、软骨、骨髓和神经血管组织等,它们主要来源于外胚层和中胚层。虽然理论上复合组织移植可来自身体任何部位,但目前试验研究仅限于肢体或其某个部分。复合组织移植在诸如先天、大面积烧伤、创伤、肿瘤等外周组织缺陷的功能及结构重建方面,具有巨大的临床应用前景。     

同种异体全手与手指复合组织移植的发展趋势

手丧失后,人的劳动能力与生活质量受到严重影响,患者迫切希望手再生,医学专家亦积极进行了同种异体肢体移植的实验研究。20世纪50年代以来,Goldwyn(1956),Schwind(1962),Lance(1971),Lapchinsky(1973),陈中伟(1981)等先后在动物身上进行异体肢体移植,均因排斥反应而失败。Benhaim(1993),Murasmatsu(1997)用新一代的强力免疫抑制药物如RS-61443、FK506等已经取得异体肢体在动物宿主身上较久存活的成绩。     

冷冻异体手指复合组织移植的临床评价

目的 评估自体拇甲皮瓣游离移植包冷冻异体手指骨－关节－肌腱－脾鞘复合组织再造拇、手术指的临床效果。方法 对再造拇、手指２７０例通过门诊复查、信访、Ｘ线睛、实验室检查、＾９９ｃＴｃＭＤＰ扫描及手术等方式进行随访,并对资料进行统计学处理与临床验证。随访时间为术后５个月～１６年,平均５年。结果 拇皮瓣携囊趾关节二块骨片包绕营养异体手指复合组织能造出外形良好的拇、手指,对掌功能优良率７１．９１％。感觉术后     

同种异体复合组织移植的免疫研究进展

目的了解同种异体复合组织移植的免疫研究进展。方法查阅相关文献,对同种异体复合组织移植的免疫特点、实验进展、临床经验等进行总结。结果同种异体复合组织位于体表,包含组织成分复杂,抗原性高。其移植后在免疫抑制剂用药方案、排斥反应的诊断以及慢性排斥反应发生率等许多方面同内脏器官移植有不同的特点。结论在下一步研究中,应吸取同种异体复合组织移植独特的经验教训,在诱导耐受、局部用药、排斥诊断等方面树立同种异体复合组织的独特标准。     

近交系大鼠腹部游离皮瓣移植模型的建立及意义

目的:为异体复合组织移植及皮肤移植免疫学研究建立一种可靠、简便而实用的动物模型。方法:以近交系Brown Norway(RT1n)大鼠为供体,Lewis(RT11)大鼠为受体,以股动静脉为血管蒂,进行腹部游离皮瓣异体移植。实验分为2组:急性排斥组(A组)术后不予免疫抑制治疗;免疫抑制组(B组)术后腹腔注射CsA剂量为20mg/kg/天。术后观察移植皮瓣的排斥情况和皮瓣存活时间,并进行组织病理学检查,以此对动物模型的可靠性和实用性进行评价。结果:A组移植皮瓣均在术后(7±1)天发生明显的逐渐加重的急性免疫排斥反应;B组移植皮瓣均可良好存活,存活时间均>100天。组织病理学检查,A组皮瓣有血管炎、毛囊炎及真皮炎症等典型急性排斥反应表现;B组皮瓣均无明显免疫排斥病理学表现。术后IL-2水平与皮瓣表面及病理学检查所见排斥反应程度相一致。结论:近交系大鼠腹部游离皮瓣移植模型是操作更为简易的血管化皮肤移植模型,其免疫排斥的发生易于观察并可稳定控制,是异体皮肤移植免疫学研究的良好动物模型。     

New composite tissue allograft model of vascularized bone marrow transplant: the iliac osteomyocutaneous flap

Vascularized bone marrow transplant (VBMT) induces donor-specific chimerism in experimental models across the major histocompatibility barrier. An experimental model for immunotolerance studies should sustain a high antigenicity with low morbidity. Accordingly, we introduced an iliac bone osteomusculocutaneous (IBOMC) transplant model in rat. It consists of a large skin component and an abundant bone marrow cells (BMC) population. We tested this model with isograft transplantations between Lewis rats (RT1^l) and with allograft transplantation between Lewis-Brown Norway (LBN RT1^l + n) donors and Lewis (RT1^l) recipients under low dose of cyclosporine A monotherapy. Immunologic responses were tested for donor cell engraftment and chimerism induction. All isografts survived indefinitely and allografts were viable at 200 days post-transplant under low dose of cyclosporine A. Microangiography of the graft revealed preservation of skin, muscle, and bone components. Histologic examination confirmed viability of all allograft components without signs of rejection. Long-term engraftment of donor-origin (RT1ⁿ) BMC was confirmed by donor-specific chimerism (1.2%) in peripheral blood and bone marrow (1.65%) compartments and by engraftment into lymphoid organs of recipients. The IBOMC transplant proved to be a reliable composite tissue allotransplantation (CTA) model. Moreover, because of its robust bone marrow component and large skin component, it is applicable to studies on immunologic responses in CTA.     

Vascularized composite tissue allotransplantation – state of the art

Vascularized composite tissue allotransplantation is a viable treatment option for injuries and defects that involve multiple layers of functional tissue. In the past 15 yr, more than 150 vascularized composite allotransplantation (VCA) surgeries have been reported for various anatomic locations including – but not limited to – trachea, larynx, abdominal wall, face, and upper and lower extremities. VCA can achieve a level of esthetic and functional restoration that is currently unattainable using conventional reconstructive techniques. Although the risks of lifelong immunosuppression continue to be an important factor when evaluating the benefits of VCA, reported short‐ and long‐term outcomes have been excellent, thus far. Acute rejections are common in the early post‐operative period, and immunosuppression‐related side effects have been manageable. A multidisciplinary approach to the management of VCA has proven successful. Reports of long‐term graft losses have been rare, while several factors may play a role in the pathophysiology of chronic graft deterioration in VCA. Alternative approaches to immunosuppression such as cellular therapies and immunomodulation hold promise, although their role is so far not defined. Experimental protocols for VCA are currently being explored. Moving forward, it will be exciting to see whether VCA‐specific aspects of allorecognition and immune responses will be able to help facilitate tolerance induction.     

局部转染CTLA-4Ig抑制大鼠异体复合组织移植急性排斥反应的研究

目的：观察腺病毒介导融合基因细胞毒性T淋巴细胞相关抗原-4（cytotoxic T-lymphocyte associated antigen-4,CTLA-4Ig）局部转染大鼠同种异体移植的复合组织对急性排斥反应的抑制作用。方法：以近交系Brown Norway大鼠为供体,Lewis大鼠为受体,采用腹部游离皮瓣作为异体复合组织移植（composite tissue allotransplantation,CTA）模型。将受者分为3组,A组（空白对照组）：异体皮瓣离体保存时不感染腺病毒,只灌注PBS溶液;B组（阴性对照组）：异体皮瓣离体保存时灌注携带增强型绿色荧光蛋白的重组腺病毒（Ad—EGFP）;C组（基因治疗组）：异体皮瓣离体保存时灌注AdCTLA-4Ig。术后观察各组移植皮瓣的排斥情况及存活天数,进行组织病理学检查,并观察CTLA-4Ig在移植组织中的表达情况及对急性排斥反应的抑制作用。结果：①A组、B组皮瓣移植物平均生存时间分别为（7．8±1．5）天和（7．1±1．6）天,C组移植皮瓣平均存活时间为（10．4±2．3）天,C组存活期长于A组和B组,差异有统计学意义（P〈0．01）;②移植皮瓣病理学检查：术后第7天,A组与B组移植皮瓣均发生严重急性排斥反应,而C组排斥反应较A组和B组轻微,但C组术后第11天也表现出严重急性排斥反应;③移植前后血清白细胞介素2（interleukin-2,IL-2）水平：各组移植术后早期发生急性排斥反应时,IL-2均有明显升高,但实验组血清IL-2水平在第3天、第7天时均明显低于两对照组（P〈0．01）。结论：建立了一种新的异体复合组织移植局部基因转染模型,皮瓣灌注AdCTLA-4Ig能获得融合基因在移植复合组织中的表达,局部产生的CTLA-4Ig能抑制急性排斥反应的发生,延长移植物存活时间。     

An alternative model of composite tissue allotransplantation: groin–thigh flap

This study focuses on development of a simpler and nonfunctional model that includes all the same tissue components as the traditional hind limb allotransplantation in rats. Adult male inbred Wistar rats (WF, RT1^u) weighing 250–300 g were used as syngeneic ( n  = 12) donors and recipients of a new experimental model for composite tissue allotransplantation. In the allogenic group ( n  = 4), adult male Brown Norway rats (BN, RT1ⁿ) weighing 200–250 g were used as donors. A groin–thigh osteo-myocutaneous flap, composed of skin (groin), muscle (thigh), and bone (2/3 femur), based on the femoral vessels and superficial epigastric vessels, was developed for composite tissue allotransplantation. All the flaps were successful except for two dying soon postoperatively. Histology confirmed vessel patency in the syngeneic group and acute rejection in the allogenic group. The total operative time was shortened compared with the standard and other modified models of rat hind limb allotransplantation. Advantages of this new model include its simplicity, relative purity, and the more humanistic fact that it does not cause claudication to the animals as does standard orthotopic hind limb transplantation, or extra-deformity to the recipients as does the heterotopic hind limb model.     

近交系大鼠后肢移植模型的建立及意义

目的:介绍异体复合组织移植研究中操作难度较大的大鼠后肢移植模型的建立方法,操作体会及此动物模型在复合组织移植中的意义。方法:以近交系BrownNorway(RT1n)大鼠为供体,Lewis(RT11)大鼠为受体,吻合股动、静脉为供血血管,进行近交系大鼠后肢异体移植。实验分为2组:急性排斥组(A组)术后不予免疫抑制治疗;免疫抑制组(B组)术后腹腔注射FK506剂量为1mg/kg/天。术后观察移植肢体的排斥情况及其存活时间,并取皮肤进行组织病理学检查,以此对动物模型的可靠性和实用性进行评价。结果:A组移植皮瓣均在术后(4±1)天发生明显的逐渐加重的急性免疫排斥反应;B组移植肢体均可良好存活,存活时间均>100天。皮肤组织病理学检查上,A组有血管炎、毛囊炎及真皮炎症等典型急性排斥反应表现;B组均无明显免疫排斥病理学表现。术后IL-2水平与肢体外观表现及病理学检查所见排斥反应程度相一致。结论:近交系大鼠后肢移植模型是得到广泛承认的复合组织移植模型,也是最具挑战性的动物模型之一,完善近交系大鼠后肢移植模型的建立方法,使模型不断规范化,对复合组织异体移植研究的发展具有重要意义。     

Near‐infrared lymphography as a minimally invasive modality for imaging lymphatic reconstitution in a rat orthotopic hind limb transplantation model

Wider application of vascularized composite allotransplantation (VCA) is limited by the need for chronic immunosuppression. Recent data suggest that the lymphatic system plays an important role in mediating rejection. This study used near‐infrared (NIR) lymphography to describe lymphatic reconstitution in a rat VCA model. Syngeneic (Lewis–Lewis) and allogeneic (Brown Norway–Lewis) rat orthotopic hind limb transplants were performed without immunosuppression. Animals were imaged pre‐ and postoperatively using indocyanine green (ICG) lymphography. Images were collected using an NIR imaging system. Co‐localization was achieved through use of an acrylic paint/hydrogen peroxide mixture. In all transplants, ICG first crossed graft suture lines on postoperative day (POD) 5. Clinical signs of rejection also appeared on POD 5 in allogeneic transplants, with most exhibiting Grade 3 rejection by POD 6. Injection of an acrylic paint/hydrogen peroxide mixture on POD 5 confirmed the existence of continuous lymphatic vessels crossing the suture line and draining into the inguinal lymph node. NIR lymphography is a minimally invasive imaging modality that can be used to study lymphatic vessels in a rat VCA model. In allogeneic transplants, lymphatic reconstitution correlated with clinical rejection. Lymphatic reconstitution may represent an early target for immunomodulation.     

Immunologic approaches to composite tissue allograft

This article discusses the immunologic principles and the most promising immunologic approaches for composite tissue allograft tolerance. We have previously reviewed some of the pharmacologic approaches for composite tissue allo-transplantation. In this review, we will summarize the range of options that may address the challenge of transplantation in reconstructive surgery.     

Composite tissue allotransplantation of the hand and face: a new frontier in transplant and reconstructive surgery

Each year an estimated 7-million people in the USA need composite tissue reconstruction because of surgical excision of tumors, accidents and congenital malformations. Limb amputees alone comprise over 1.2 million of these. This figure is more than double the number of solid organs needed for transplantation. Composite tissue allotransplantation in the form of hand and facial tissue transplantation are now a clinical reality. The discovery, in the late 1990s, that the same immunotherapy used routinely in kidney transplantation was also effective in preventing skin rejection made this possible. While these new treatments seem like major advancements most of the surgical, immunological and ethical methods used are not new at all and have been around and routinely used in clinical practice for some time. In this review of composite tissue allotransplantation, we: (i) outline the limitations of conventional reconstructive methods for treating severe facial disfigurement, (ii) review the history of composite tissue allotransplantation, (iii) discuss the chronological scientific advances that have made it possible, (iv) focus on the two unique clinical scenarios of hand and face transplantation, and (v) reflect on the critical issues that must be addressed as we move this new frontier toward becoming a treatment in mainstream medicine.