非协调性异种气管移植的实验研究

目的探索异种气管移植免疫排斥反应特点,为解决供体气管来源提供新方向,并为研究肺移植继发的气道阻塞性疾病(OAD)建立理想的动物模型。方法建立SD大鼠颈部肌肉瓣包裹移植气管模型,以深低温冻储同种异体气管移植为对照,通过组织化学检查,免疫荧光检查,流式细胞术等方法,观察冷冻与非冷冻豚鼠—大鼠非协调性异种气管移植的成活情况,分析其免疫排斥反应的特点和机制。结果颈部肌肉瓣包裹深低温冻储同种异体SD大鼠长期存活。豚鼠—大鼠冷冻异种气管移植最长成活14 d,平均(13.2±0.75)d;新鲜异种气管移植最长成活9 d,平均(8.0±1.09)d。组织学检查,异体移植气管基本正常,气管通畅度大于80%。异种移植气管呈急性排斥反应表现,移植物大量嗜酸粒细胞,淋巴细胞,单核巨嗜细胞浸润;受体IgM,IgG,C3沉积;外周血CD4+T、CD8+T淋巴细胞明显升高;黏膜上皮剥脱,软骨失去活性;气管通畅度小于50%。以上表现随时间延长而加重,冷冻组弱于非冷冻组。结论细胞免疫反应参与的体液免疫反应为主的急性排斥反应是豚鼠—大鼠非协调性异种气管移植免疫反应特点。深低温冻储消减供体抗原,在一定范围内延长异种移植物成活时间。     

同种异体半月板联合骨软骨移植的实验研究

目的:探讨新鲜同种异体半月板骨软骨联合移植治疗胫骨平台毁损伤后骨关节炎的疗效。方法:成年新西兰大白兔36只,随机分为A、B、C3组,各12只。A组行右膝内侧半月板连同胫骨平台骨软骨移植,克氏针交叉固定骨块。B组行右膝内侧半月板移植,左膝内侧半月板取出制备新鲜冷冻半月板。C组行左膝内侧新鲜冷冻半月板移植。术后4、8、12周分批取材行大体观察、组织学检查和胫骨平台软骨氨基己糖(GAG)测定。结果:12周时A组移植胫骨平台软骨与B、C组半月板移植术后的内侧胫骨平台软骨氨基己糖含量差异无统计学意义;A、B组移植的半月板纤维软骨细胞数差异无统计学意义;A组半月板移植的纤维软骨细胞数多于C组。结论:新鲜同种异体半月板骨软骨联合移植能修复胫骨平台毁损伤。     

复合自体骨髓的冷冻异体犬足趾关节移植实验研究

目的探讨经过多重钻孔并复合自体骨髓的冷冻异体犬足趾关节移植的疗效. 方法 24只健康成年杂交犬,制备双侧后肢第2足趾近侧趾间关节1.5 cm缺损模型,共48侧,随机分成A、B、C 3组(n=16).分别采用新鲜自体趾间关节(A组)、经钻孔并复合自体新鲜骨髓的冷冻异体趾间关节(B组)及单纯冷冻异体趾间关节(C组)修复缺损.于术后1、3、6和12个月分别行X线摄片和组织病理学检查,了解移植骨关节的成活情况. 结果根据移植关节术后X线片和组织学改变,犬趾骨关节移植后的病变可分为轻度、中度和重度变性3级.A组移植骨关节3～12个月始终表现为轻度变性;B组移植骨关节1～6个月为轻度变性,骨孔中央软骨内成骨现象明显,12个月部分移植骨关节为中度变性;C组从1个月出现移植骨关节中度变性,3个月移植骨关节重度变性. 结论冷冻异体犬足趾关节内多重钻孔并复合自体新鲜骨髓,能有效延缓异体骨关节的早、中期变性,单纯冷冻异体骨关节移植后早期可能发生严重变性.     

超低温冷冻保存后同种异体神经移植的实验研究

目的　探索大鼠同种异体神经移植的可行性。方法　取Wistar大鼠坐骨神经 ,经超低温冷冻保存后移植于SD大鼠坐骨神经缺损处。分成超低温冷冻同种神经移植组 (A)、新鲜同种神经移植组(B)、及自体神经移植组 (C)。 3组均在术后 3、8、12、16周行大体观察 ,检测形态学、电生理变化及血清IL 2、TNF水平。结果　A、C组的腓肠肌萎缩 ;足无明显畸形 ,趾无缺损、无溃疡。B组的腓肠肌萎缩 ;足部溃疡伴趾部分缺损。A、C组在术后 8周刺激神经移植段近端有动作电位出现 ,B组在术后 12周出现。A组动作电位的波幅较B组高。血清IL 2 ,C组与B组差别有显著性 (P <0 .0 5 ) ,A组与C组比较差别无显著性 (P >0 .0 5 )。光镜下A组空泡变性、炎性细胞浸润少。电镜下见髓鞘厚薄基本相同 ,轴突密度高 ,雪旺细胞发育较完善 ,明显优于B组。结论　超低温冷冻保存能降低同种异体神经的抗原性 ,在不用免疫抑制剂情况下 ,动物用同种异体神经移植是可行的     

自体表皮细胞悬液移植修复全层皮肤缺损创面的动物实验研究

目的探讨自体表皮细胞悬液移植技术用于全层皮肤缺损创面修复的适宜密度。方法取健康清洁级成年SD大鼠40只,雌雄不限,体质量210~230 g;根据细胞移植密度不同,随机分为高、中、低细胞密度及空白组(分别为A、B、C、D组,n=10)。取大鼠背部皮肤培养表皮细胞,并制作大鼠全层皮肤缺损创面抗挛缩模型。其中A、B、C组分别将0.2 mL密度为1×10~6、1×10~5、1×10~4个/cm~2的自体表皮细胞悬液移植至创面处,D组给予等量限制性角质形成细胞无血清培养基;取成年Wistar大鼠背部皮肤制备同种异体皮,覆盖各组创面。术后观察大鼠存活情况,于术后7、14、21 d大体观察同种异体皮成活、脱落及创面愈合情况,同种异体皮脱落后计算创面愈合率;21 d时取材行组织学及免疫组织化学染色,观察创面修复情况。结果术后大鼠均存活至实验完成。各组大鼠同种异体皮随时间延长逐渐成活,干燥并开始脱痂;至21 d同种异体皮基本脱落后A、B组创面可见成片上皮,C组创面可见少量菲薄上皮,D组创面无上皮形成。术后21 d同种异体皮脱落后,A、B、C、D组创面愈合率分别为62.9%±9.6%、64.2%±9.1%、38.5%±5.7%、22.7%±5.5%,A、B组创面愈合率显著高于C、D组(P0.05),C组高于D组(P0.05),A、B组间比较差异无统计学意义(P0.05)。组织学观察示,A、B、C组愈合的创面上皮层可见鳞状上皮细胞,A、B组表皮分层明显,C组表皮层薄、可见炎性细胞浸润,D组为肉芽组织。免疫组织化学染色观察示,A、B、C组表皮-真皮连接层Ⅳ型胶原和Ⅶ型胶原表达呈阳性,D组无表皮层呈阴性;A、B组Ⅳ、Ⅶ型胶原表达阳性细胞百分比显著高于C组(P0.05),A、B组间比较差异无统计学意义(P0.05)。结论自体表皮细胞悬液移植技术在大鼠全层皮肤缺损创面修复中可重构皮肤,1.0×10~5个/mL为创面修复的适宜移植密度。     

异体气管移植再血管化与再上皮细胞化研究进展

目的探讨同种异体气管移植再血管化与再上皮细胞化的研究进展.方法广泛查阅近期相关文献,介绍一种先将同种异体移植段气管大网膜包裹,血管化后再种植自体上皮细胞后原位移植的方法.结果与一期原位移植加大网膜包裹相比,增加上皮细胞覆盖率,使之最接近自体生理条件.结论这一方法若能成功,可进一步减少移植段气管免疫排斥反应,防止其塌陷,延长患者生存时间.     

绿茶多酚保存同种异体神经移植体的实验研究

[目的]研究绿茶多酚溶液保存的同种异体神经修复大鼠坐骨神经缺损的效果.[方法] 48只成年雄性Wista大鼠,随机分为4组,每组12只,将坐骨神经在梨状肌孔下5 mm 处切除1.0 cm, 神经缺损分别用4种移植物桥接.A组:自体神经移植;B组:新鲜异体神经移植;C组:经冷冻处理的异体神经移植;D组:用绿茶多酚保存的异体神经移植.术后6、12周通过大体观察、电生理学检查、组织学观察、透射电镜观察、图像分析与定量学检测评价各组修复神经缺损的效果.[结果]A、D组间差异无统计学意义(P＞0.05),A组、D组的各项指标均优于B组、C组(P＜0.05或P＜0.01).[结论]绿茶多酚溶液保存的同种异体神经是良好的神经移植替代材料.     

一步法联合冻存提高大鼠胰岛冻存质量的研究

目的探讨提高大鼠胰岛冻存质量的方法,以期为建立胰岛库奠定基础。方法将受体鼠分为实验组A组:即一步法联合冻存的胰岛移植组;对照组B组:新鲜的胰岛移植组;对照组C组:逐步法冻存的胰岛移植组。观察3组之间胰岛收获率,活性及移植后效果等方面的差异。结果纯化后收获大鼠胰岛每只(826.87±93.24)IEQ。A组平均胰岛收获率为(87±4)%,高于C组的胰岛收获率(81±4)%。A组和C组经过胰岛刺激素释放实验后均有较B组高的基础胰岛素释放量,但刺激指数则明显低于B组的637.3±39.5。胰岛移植入糖尿病鼠受体后,A组和B组在移植后1周即恢复血糖为正常值,并维持到观察结束。而C组中则需要较长时间纠正血糖到正常。移植(2011.14±114.22)IEQ胰岛在A组和B组可达到100%纠正糖尿病。结论采用全新的细胞内低温保存液(HTS)结合细胞冻存液(DMSO)对大鼠胰岛进行一步法冻存取得了明显优于用DMSO逐步冻存的效果。     

重组人骨形态蛋白复合肌瓣诱导自体异体气管软骨再生

目的在肌瓣包裹气管移植段促进血液循环重建的基础上复合重组人骨形态蛋白(rhBMP)-2,观察rhBMP-2对自体及异体移植段气管软骨的诱导作用。方法16条犬随机等分为4组,取颈部5环气管为移植段。A1组:自体复合BMP/I型胶原组;A2组:自体移植组;B1组:异体复合BMP/I型胶原组;B2组:异体移植组。术后4周取材,观察比较大体及组织学改变。结果A1组软骨再生最明显(P<0.05);A2、B1组均有不同程度的软骨再生;B2组软骨再生最少。结论在肌瓣包裹移植段气管的基础上,BMP可明显诱导移植段软骨的再生,且自体移植软骨再生明显。     

大鼠再生移植脾片量的观察

目的研究移植脾片的再生量以及与移植量大小、移植部位的关系.方法将相同移植脾片量移植在肝表面(A组,n=20)和大网膜(B组,n=20),A,B组脾片重量(188.77±19.09)mg,将不同量脾片移植在大网膜(C组,n=20),C组脾片重量为(91.46±17.66)mg.移植前及移植后(6,8周)测量脾片重量.结果相同重量的大块脾片移植在肝表面(A组)及大网膜(B组),其6,8周再生量明显低于移植前重量,(P<0.01);小块脾片大网膜移植组(C组)脾片重量在移植后8周时明显重于6周时,但仍低于B组8周时的重量(P<0.05).结论不同部位移植脾片再生过程是一样的,相同重量脾片移植在肝表面及大网膜的再生量无差异;不同重量脾片移植在大网膜上再生量明显不同.     

Repair of long tracheal defects with cryopreserved cartilaginous allografts.

Tracheoplasties with various autografts (cartilage, periosteum, pericardium) have been used in the treatment of long-segment tracheal stenosis. Previous studies have shown that cartilage allografts survive transplantation on a long-term basis in various sites of the body. In this study we set out to determine if cryopreserved cartilage and cryopreserved tracheal allografts would survive when used to cover tracheal defects in animals. A rectangular defect (2.8 +/- 0.3 cm long and incorporating 50% of tracheal circumference) was created in the thoracic trachea of 18 piglets. The defect was covered with the excised tracheal segment in 6 (group A, control group), with a cryopreserved tracheal allograft in 6 (group B), and with a cryopreserved cartilage allograft harvested from the scapula in 6 (group C). The allografts were cryopreserved, by a standard slow-freezing technique, at -80 degrees C for more than 21 days. All animals survived the grafting procedure and were killed after 2 months. None had signs of airway obstruction. Using the trachea above the defect as the standard, the mean sagittal narrowing of the airway in the repaired trachea was 0.4 mm in group A, 0.7 mm in group B, and 0.6 mm in group C; the coronal diameter in normal and grafted trachea was similar. The lumen of all grafts was lined by regenerating respiratory epithelium, and cilia were seen in many. Some cartilage was reabsorbed in group A and B but cartilage islands were present in all. In group A, reabsorption of cartilage was minimal. These findings suggest that segments of trachea or cartilage allografts can be cryopreserved, stored, and, subsequently, used when necessary for tracheoplasty.     

Effect of cryopreservation period on rat tracheal allografts.

BACKGROUND: The effect of cryopreservation on tracheal allogenicity is still unclear. Therefore, in this study, we assessed the effect of cryopreservation period on tracheal allografts in 62 rats. METHODS: Each transplant consisted of a 3-ring segment of the trachea harvested from 8 Lewis rats, immersed in preservation solution, and cryopreserved and stored in a Bicell biofreezing vessel in a deep freezer at -80 degrees C. Six tracheal grafts without cryopreservation that underwent a heterotopically syngeneic transplantation into the omentum served as controls. Forty-eight tracheal segments were randomly assigned to 8 groups according to period of cryopreservation, which ranged from 0 to 12 months (0, 0.5 [2 weeks], 1, 2, 3, 6, 9 and 12 months). The cryopreserved grafts were then thawed and heterotopically implanted into the omentum of recipient Brown-Norway rats. After 28 days, the tracheal segments were then evaluated histologically. RESULTS: All isografts in Group 1 were intact, whereas the allografts undergoing a particularly shorter period of cryopreservation showed a more stenotic lumen. Prolonged periods of cryopreservation tended to show decreasing tendencies of viability of chondrocytes, mononuclear cell infiltration and sub-epithelial thickness, whereas all allografts showed a uniformly denuded epithelium, irrespective of the length of cryopreservation. CONCLUSIONS: A longer period of cryopreservation may help to maintain a better patency of tracheal allografts by preventing an allogeneic response. Reduced tracheal allogenicity may be associated with a decreased viability of chondrocytes by cryopreservation.     

Successful tracheal transplantation using cryopreserved allografts in a rat model.

OBJECTIVES: The purpose of this study was to determine the appropriate cryopreservation period of tracheal allografts based on morphological and immunological findings and to test the possibility of tracheal transplantation in rats using cryopreserved allografts without immunosuppression. METHODS: Morphological and immunological studies were performed to compare the differences between non-cryopreserved grafts and cryopreserved grafts. Orthotopic tracheal transplantation using cryopreserved allografts, non-cryopreserved allografts, and non-cryopreserved autografts was performed and the rejection score of each group was evaluated. RESULTS: Epithelial cells were lost when the grafts were cryopreserved for more than 20 days. Immunohistochemical staining of the trachea revealed that the MHC classII antigen was expressed on normal epithelium. These findings suggest that cryopreservation for more than 20 days decreased the antigeneicity of allografts because of epithelial desquamation. All rats that received allografts cryopreserved for more than 20 days survived until the scheduled sacrifice day. Microscopically, cryopreserved allografts that had been preserved for more than 20 days had a significantly lower rejection score than that of non-cryopreserved allografts (P < 0.05). CONCLUSIONS: We conclude that the appropriate period for cryopreservation of allografts would be 20 days or more, because cryopreservation for more than 20 days depleted epithelium, which possessed the MHC classII antigen. Therefore, a longer period of cryopreservation decreases the antigeneicity of allografts. Rat tracheal transplantations using cryopreserved allografts is possible without immunosuppression when the grafts have been cryopreserved for more than 20 days.     

Heterotopic transplantation of cryopreserved tracheae in a rat model.

INTRODUCTION: The successful use of cryopreserved tracheal allografts in canine models suggests their use in humans. The grade of genetic difference, the mechanism of revascularisation and the method of cryopreservation are not clearly defined. The purpose of our study was to investigate the rejection of tracheal transplants in a standardised heterotopic rat model using different forms of cryopreservation. METHODS: Tracheae from Brown Norway rats were implanted into the omentum from Brown Norway rats or Lewis rats. We transplanted fresh isografts or allografts and pretreated isografts or allografts. Cryopreservation was performed in a medium containing 10% dimethyl sulphoxide at -80 degrees C for 28 days (I) or -196 degrees C for 84 days (II) or without medium at -80 degrees C for 28 days (III). The transplants were excised after 7 and 21 days, respectively. RESULTS: Histological examinations revealed normal structure and function of isografts after 21 days. In the cryopreserved isograft, the epithelium had disappeared and the tracheal lumen was partially obstructed by a non-compact fibrous tissue. In the fresh allografts, the epithelium was replaced by aggressive fibrous tissue, infiltrating the membranous part of the trachea and occluding the tracheal lumen. The cartilage was vital without any sign of rejection. In the cryopreserved allografts, the tracheal lumen was obstructed by dense fibrous tissue with an inflammatory reaction. The cartilage of cryopreserved allografts (II) and (III) had lost the nuclei corresponding to non-vital tissue. Only in the cryopreserved allografts (I) did we find nodular regeneration at the edges of the cartilaginous bow. CONCLUSIONS: The heterotopic transplantation model allows the study of the mechanisms leading to tracheal obstruction. Cryopreservation was found to have no clear advantage in reducing transplant immunogenicity. Cryopreservation leads to significant damage to the cartilage, the intensity of which is dependent on the mode of cryopreservation.     

Revascularization of canine cryopreserved tracheal allografts

Background. We examined the blood supply of a cryopreserved tracheal allograft and its morphohistologic changes after transplantation.

Methods. In each of 22 dogs, a five-ring tracheal segment was replaced by one of the following tracheal grafts: fresh autografts (n = 8), cryopreserved tracheal allografts (n = 8), or fresh allografts (n = 6). The cryopreserved tracheal allografts were preserved at −196°C for 60 days. No immunosuppressant was given to any of the animals. All grafts were retrieved at 1 and 12 weeks and assessed by microangiography and histology.

Results. The epithelial denudation and the revascularization of the transverse intercartilaginous arteries were recognized within 7 days as common to each of the three types of grafts. In the cryopreserved tracheal allografts, neither cartilage degradation nor graft shrinkage occurred at 7 days. However, the recanalized transverse intercartilaginous arteries completely disappeared at 12 weeks, and marked shrinkage occurred; the cartilage cells were accompanied by karyolysis and were significantly decreased in number (p < 0.05). Recanalization of the transverse intercartilaginous arteries was also demonstrated in the fresh allografts; however, necrosis abruptly occurred as a result of acute rejection responses.

Conclusions. Cryopreservation of a tracheal allograft provided sufficient reduction of the acute rejection responses, and blood supply to the cryopreserved tracheal allograft was established through the recanalized transverse intercartilaginous arteries within 7 days; however, subsequent chronic rejection responses resulted in occlusion of the transverse intercartilaginous arteries and atrophy.     

Experimental small bowel transplantation using newborn intestine in rats: III. Long-term cryopreservation of rat newborn intestine

BACKGROUND: If long-term organ cryopreservation can be attained, a significant achievement will have been made to address the problem for donor shortage. Fetal intestine has been known to revascularize naturally without vascular anastmosis. The authors have confirmed previously that the newborn intestine also could develop to maturity in the host omentum. Here, the authors examined whether the cryopreserved newborn intestine could revascularize in the syngeneic combination using the 2 different solutions and whether cryopreservation affect their antigenicity in the allogeneic combination. METHODS: Inbred rat strains of LEW (MHC haplotype; RT1(l)) and BN (RT1(n)) were used. LEW newborn intestinal grafts were stored in RPMI-1640 or University of Wisconsin solution with 10% DEMSO (n = 10 in each group). The grafts were placed into a cold (4 degrees C) preservation solution for 30 minutes and then placed into a freezing chamber and cooled to -80 degrees C at -1 degrees C/min after 12 hours quenched to -180 degrees C in liquid nitrogen for longer than 30 days. Then, the cryopreserved grafts under the 2 different solutions were transplanted syngenicaly (LEW to LEW). The cryopreserved BN grafts also were implanted into the LEW omentum pouch. The allotransplantation was received with a 14-day high-dose course of tacrolimus (0.64 mg/kg, intramuscularly). The grafts were evaluated histologically at 4 weeks after transplantation. Fresh newborn intestines implanted in this syngeneic and allogeneic combination were evaluated as each control group. RESULT: In the syngeneic combination, more than 90% of the mature intestine were obtained. There was no significant difference among the different solution and the fresh group. However, in the allogeneic combination, both fresh and cryopreserved grafts were histologically poor. CONCLUSIONS: This is the first report showing that long-term cryopreservation was not harmful for neovascularization of newborn intestine. Long-term cryopreservation did not reduce the antigenicity of the newborn intestine. J Pediatr Surg 36:602-604.     

Function of cryopreserved arterial allografts under immunosuppressive protection with cyclosporine A

Purpose: Cryopreserved arterial allografts may be used for arterial reconstructive procedures. In this experimental study cryopreserved arteries were used as autografts and as allografts with or without immunosuppression with cyclosporine A.Methods: In group A (three dogs, six bilateral grafts) cryopreserved carotid artery autografts were implanted. In groups B and C female mongrel dogs (three dogs and six bilateral grafts in each group) received cryopreserved male carotid artery allografts. Dogs in group C were treated with cyclosporine A (25 mg/kg/day). After 3 months of implantation patency was assessed by angiography. Contractile responses to KCl and phenylephrine (Phe) and the endothelium-dependent relaxation response to methacholine (Met) were examined in segments of the grafts after excision. Medial thickness was assessed semiquantitatively. The grafts were stained for sex chromatin analysis to determine the origin of cells in allografts.Results: Patency: group A, 100% (6 of 6), group B, 66.6% (4 of 6), and group C, 100% (6 of 6). Functional responses: before implantation, after thawing, 2.7 ± 0.5 mN (KCl), 4.8 ± 1.0 mN (Phe), and 0.0% ± 0.0% (Met), group A, 36.9 ± 10.6 mN (KCl), 31.5 ± 14.4 mN (Phe), and 59.3% ± 20.4% (Met), group B, 0 for all agents used, group C, 34.0 ± 7.5 mN (KCl), 28.8 ± 7.0 mN (Phe), and 46.2% ± 3.2% (Met). Morphologic characteristics: the media of grafts in group B showed significant thinning ( p < 0.05). Smooth-muscle cells in vessel walls of grafts in group C were of female origin.Conclusion: Arteries showed no function and loss of endothelial integrity after cryopreservation and thawing. After 3 months of implantation cryopreserved arterial autografts and allografts under immunosuppressive treatment with cyclosporine A showed 100% patency and return of functional responses resulting from repopulation of grafts by host cells. (J Vasc Surg 1996;24:876-82.)     

Successful allotransplantation of cryopreserved tracheal grafts with preservation of the pars membranacea in nonhuman primates.

OBJECTIVE: This study was performed to confirm the feasibility of cryopreserved tracheal allotransplantation in primates, the anatomy and immunology of which are considered to be more closely related to those of humans than those of other animals. METHODS: Cryopreserved tracheal allotransplantations were performed in 3 recipient primates. In the control group fresh tracheal allotransplantations were performed in 2 primates (control A), and a tracheal allotransplantation with a simply frozen tracheal graft was performed in 1 primate (control B). Monthly bronchoscopic examinations, histologic examinations, electron microscopic examinations, and immunohistochemical investigations were performed in each of the primates. RESULTS: In the cryopreserved tracheal allotransplantation group, 3 recipient monkeys were killed on the 35th, 144th, and 387th postoperative days, respectively. All grafts were incorporated by the recipient trachea without stenosis in the cryopreserved group. In the control group 2 recipient monkeys were killed on the 93rd postoperative day (control A), and one was killed on the 84th postoperative day (control B). Severe stenosis was observed after the transplantation in all of the control monkeys. Immunologic reactions appeared to be attenuated by the cryopreservation, whereas T cell-mediated immunologic rejection (control A) and loss of cartilage viability (control B) were considered to be the causes of graft failure in the control group. CONCLUSION: The immunogenicity of the tracheal allografts was reduced by cryopreservation, and cryopreserved tracheal allotransplantation was successful in our primate model. Further investigation of cryopreserved tracheal allotransplantation with regard to proper clinical applications and the limitations of the procedure should be performed.     

A novel MyD88 inhibitor attenuates allograft rejection after heterotopic tracheal transplantation in mice

BackgroundAfter lung transplantation, the major complication limiting the long-term survival of allografts is obliterative bronchiolitis (OB), characterized by chronic rejection. Innate immune responses contribute to the development of OB. In this study, we used a murine heterotopic tracheal transplantation mouse model to examine the effects of a newtype of innate immune inhibitor, TJ-M2010–5.MethodsSyngeneic tracheal grafts were transplanted heterotopically from C57BL/6 mice to C57BL/6 mice. Allografts from BALB/c mice were transplanted to C57BL/6 mice. The allograft recipients were treated with TJ-M2010–5, and anti-mouse CD154 (MR-1). The grafts were harvested at 7, 14, and 28 days and evaluated by histological and real-time RT-PCR analyses.ResultsIn untreated allografts, almost all epithelial cells fell off at 7 days and tracheal occlusion reached a peak at 28 days. However, the loss of the epithelium and airway obstruction were significantly improved in mice treated with TJ-M2010–5 combined with MR-1. The relative mRNA expression levels of pro-inflammatory cytokines were upregulated in allogeneic tracheal grafts, and treatment with the two drugs reduced the production of pro-inflammatory cytokines and infiltration of inflammatory cells.ConclusionsIn heterotopic tracheal transplantation models, TJ-M2010–5 combined with MR-1 could ameliorate the development of OB.