体液免疫在异品系大鼠腹主动脉移植硬化中的作用

目的： 探索体液免疫在移植动脉硬化演变过程中的作用。方法: 建立大鼠腹主动脉移植硬化模型，HE染色和光镜下检查植入的腹主动脉病理学改变，计算机图像分析系统自动测出其管腔面积、内膜面积和中膜面积。间接免疫荧光法检测植入的腹主动脉壁IgG、IgM、C3沉积情况。结果: 异品系移植组术后60 d腹主动脉管腔明显缩小，内膜显著增厚，中膜变薄。增生的腹主动脉内膜主要由单核/巨噬细胞和平滑肌细胞构成，中膜层平滑肌细胞坏死，数量减少，弹力膜断裂。IgM、C3在术后各组各时点动脉壁上均未见沉积现象。IgG在异品系移植组术后7 d、15 d时动脉中膜层呈强荧光沉积，30 d后IgG荧光消失。结论: 体液免疫因子IgG可能参与了异品系大鼠移植腹主动脉硬化的过程。     

后肢急性缺血大鼠模型的构建及评估

背景：目前国内广泛采用大鼠肢体缺血模型对肢体缺血的病理过程和治疗方法进行研究,但在模型的构建及评估上存在一定争议,故急需一种可靠、经济、制作方便的疾病模型。目的：探索不同方式制备的SD大鼠后肢急性缺血模型患肢缺血的程度、持续时间和变化规律,寻找肢体缺血程度适中、稳定,维持时间较长的模型制备方法。方法：随机将72只SD大鼠等分为4组：A组大鼠给予假手术,分离肾动脉水平以下的腹主动脉和髂腰动脉、右股浅动脉、腘动脉、隐动脉;B组大鼠切断右股浅动脉、腘动脉、隐动脉,切除右股浅动脉,建立后肢急性缺血模型;C组大鼠结扎腹主动脉、两侧腹壁阴部动脉,建立后肢急性缺血模型;D组大鼠结扎腹主动脉、髂腰动脉和腰动脉,建立后肢急性缺血模型。结果与结论：造模后2,4,6周,以不同方法建立后肢急性缺血模型的B、C、D组大鼠右后肢肌力弱于A组;4周D组肌力弱于B、C组;6周B、D组肌力仍有弱于C组的趋势。造模后2,4,6周,B、C、D组右后肢静脉血氧分压均低于A组;造模后2,4周,D组低于B、C组;造模后6周D组仍低于C组。造模后2、4周,3个造模组右后肢肌组织部分肌细胞崩解,纤维结缔组织增生,毛细血管增多,炎细胞浸润,且D组病理变化最重。造模后6周,3组纤维结缔组织增生减轻,毛细血管增生、扩张、充血。提示结扎大鼠肾动脉下方腹主动脉、髂腰动脉和腰动脉的后肢缺血模型,缺血程度适中,缺血状态稳定,维持时间较长,制作方便。 中国组织工程研究杂志出版内容重点：肾移植;肝移植;移植;心脏移植;组织移植;皮肤移植;皮瓣移植;血管移植;器官移植;组织工程     

异种移植建立的大鼠腹主动脉瘤形态学特征

目的: 建立和鉴定一种新型腹主动脉瘤动物模型, 为腹主动脉瘤的进一步研究提供基础。方法: 选取豚鼠肾下腹主动脉组织1 cm, 正位替换SD大鼠同长度腹主动脉; SD大鼠腹主动脉原位离断后吻合分别作为对照。分别于术后4周动态观测和比较移植腹主动脉直径、腔面积等形态学变化; 计算机图像技术半定量分析弹力纤维、胶原纤维及平滑肌变化。结果: 存活受体中88%移植腹部主动脉血流通畅, 无移植物或吻合口狭窄, 无腔内血栓形成。4周内, 异种移植组腹主动脉直径随时间延长逐渐扩张, 与对照组有显著差异; 腹主动脉扩张率与弹力蛋白、中膜平滑肌变化呈现显著负相关。结论: 免疫炎症损伤介导的豚鼠-SD大鼠异种移植腹主动脉瘤是一稳定可靠的动物模型。     

移植动脉新生内膜平滑肌细胞来源于受体骨髓细胞的实验依据

目的： 研究大鼠移植动脉新生内膜平滑肌细胞Sry基因表达，探讨移植物动脉硬化新生内膜平滑肌细胞的来源。方法: 将雄性Wistar大鼠骨髓细胞移植到雌性大鼠体内，制备嵌合体大鼠；4周后建立大鼠腹主动脉移植慢性排斥反应模型，分为4组：雌性同系移植组、雌性异系移植组、雄性异系移植组、嵌合体异系移植组。移植术后8周，取移植动脉组织标本，进行病理组织学观察与免疫组化染色，分析移植动脉新生内膜增生及新生内膜细胞α-SMA的表达；采用显微切割技术收集新生内膜平滑肌细胞，用PCR扩增方法检测细胞Sry基因表达，分析新生内膜平滑肌细胞与受体骨髓细胞的关系。结果: 异系移植组移植动脉新生内膜中α-SMA表达阳性平滑肌细胞大量增生，致动脉内膜显著增厚，动脉壁新生内膜面积及新生内膜/中膜面积比均显著高于同系移植组(P<0.01)。PCR分析显示，嵌合体异系移植组和雄性异系移植组一致，在约225 bp处均有1条特异性扩增条带，而雌性异系移植组则无相应的核酸扩增条带。结论: 受体骨髓细胞作为移植物血管新生内膜平滑肌细胞的来源，参与移植物动脉硬化发生和发展。     

PKC和MMPs 在实验性大鼠动脉粥样硬化形成中的作用及丹参的作用机制

目的：探讨基质金属蛋白酶（MMPs）在大鼠动脉粥样硬化形成中的作用，蛋白激酶C（PKC）在MMPs表达中的作用及丹参注射液治疗动脉粥样硬化的可能机制。 方法： 将大鼠随机分为正常对照组（C组）、动脉粥样硬化模型组（M组）、丹参注射液组（D组），检测血清胆固醇、甘油三酯、低密度脂蛋白水平，免疫组化法测定主动脉PKC、MMPs的表达，结合光镜、透射电镜等方法综合评价。结果： ①血脂各成分含量M组和D组显著高于C组（P<0.01）；D组低于M组（P<0.01）。②PKC、MMP-2、MMP-9的表达M组明显高于C组（P<0.01）；D组显著低于M组(P<0.01)。PKC与MMP-2、MMP-9的表达存在正相关。③光镜下M组动脉内膜增厚，斑块形成，中膜平滑肌增厚，并有钙化、坏死；D组病变较轻。④电镜见M组胶原纤维明显增多，排列紊乱，平滑肌细胞坏死，内皮细胞大部分脱落；D组改变较轻。结论： ①MMPs在动脉粥样硬化发生、发展中起着关键作用。②PKC信号转导途径参与了动脉粥样硬化的形成，其激活可能是MMPs表达的上游机制。③PKC、MMPs活性的降低可能是丹参防治动脉粥样硬化的机制之一。     

内源性增加单个核细胞自体移植提升血管闭塞性脉管炎调节性T细胞比例

背景：自体外周造血干细胞具有多向分化潜能的特点,可促进缺血肢体新生血管形成,改善和恢复患肢的血液供应。 目的：观察自体外周血单个核细胞自体移植对血管闭塞性脉管炎大鼠的治疗作用。 方法：将24只大鼠随机分为对照组、模型组和粒细胞集落刺激因子组。在模型组和粒细胞集落刺激因子组大鼠中股动脉注射月桂酸钠建立血管闭塞性脉管炎大鼠模型。粒细胞集落刺激因子组大鼠连续5 d以重组人粒细胞集落刺激因子动员外周血单个核细胞,第7天接受外周血单个核细胞移植,对照组和模型组大鼠仅给予生理盐水。 结果与结论：与造模前相比,模型组和粒细胞集落刺激因子组大鼠造模后足背部体温及CD4+CD25+调节性T细胞比例显著降低,下肢溃疡面积明显增加;粒细胞集落刺激因子组大鼠动员后第6天白细胞数量及CD34+细胞占单个核细胞的百分比增加,外周血单个核细胞移植之后1个月时足背部体温与建模前接近,CD4+CD25+调节性T细胞比例显著上升。提示外周血单个核细胞内源性增加后进行自体移植,可提升血管闭塞性脉管炎大鼠调节性T细胞比例,有助于迅速缓解症状、促进溃疡愈合。中国组织工程研究杂志出版内容重点：干细胞;骨髓干细胞;造血干细胞;脂肪干细胞;肿瘤干细胞;胚胎干细胞;脐带脐血干细胞;干细胞诱导;干细胞分化;组织工程      

高渗盐水预处理可减轻中性粒细胞介导的肝脏缺血再灌注损伤

目的：探讨高渗盐水预处理对肝脏缺血再灌注损伤的拮抗作用及其机制。方法：建立大鼠局部肝脏缺血再灌注模型。设假手术组（sham组）、缺血再灌注组（IR组）和高渗盐水预处理组（HTS组），分别于再灌注后1 h、3 h、6 h、12 h和24 h处死大鼠，测定谷丙转氨酶（ALT）；抗凝血流式细胞仪测定中性粒细胞CD11b/CD18(Mac-1)的阳性率；RT-PCR和Western blotting分别测定肝内细胞间黏附分子1（ICAM-1）的mRNA和蛋白表达；比色法测定肝脏内髓过氧化物酶（MPO）活性；常规病理及电镜观察肝脏的病理学改变及肝脏内中性粒细胞的浸润情况。结果： ① HTS组在3 h、6 h和12 h血清ALT水平明显低于IR组（P<0.05）。②HTS组在6 h和12 h中性粒细胞Mac-1表达显著弱于IR组（P<0.05）。③HTS组肝脏MPO活性在再灌注后6 h、12 h和24 h明显低于IR组（P<0.05）。④HTS组大鼠肝脏内ICAM-1mRNA及蛋白表达明显低于IR组。⑤HTS组肝内中性粒细胞浸润、肝细胞浊肿和肝窦狭窄程度轻于IR组。结论： HTS预处理能够通过抑制中性粒细胞Mac-1和肝内ICAM-1的表达，明显抑制肝内中性粒细胞的黏附和聚集，起到拮抗肝脏缺血再灌注损伤的作用。     

伴有高血压的糖尿病大鼠主动脉的结构重建

目的 :观察伴有高血压的糖尿病 (SHRDM)主动脉结构重建的规律 ,并探讨高血糖、高血压对其影响。方法 :STZ诱导SHR大鼠建立SHRDM实验动物模型 ,。观测主动脉血管壁中膜结构成分的改变。结果 :SDDM(有高血压的糖尿病 )大鼠自 4周始主动脉中膜平滑肌相对含量和核密度、胶原纤维相对含量均大于SD组 ,弹性纤维相对含量少于SD组。SHRDM组主动脉平滑肌相对面积、C/E值大于SD和SHR组 ,但SMC核数少于SDDM ,多于SHR。结论 :糖尿病早期已出现主动脉结构重建 ,以平滑肌增生为主 ;高血压使平滑肌细胞肥大为主 ,因而SHRDM增生、肥大共存。高血压、高血糖均显著影响主动脉结构重建 ,高血压影响大于高血糖。     

阿托伐他汀对大鼠自体移植静脉内膜增生的影响

目的： 探讨新型降脂药阿托伐他汀对自体移植静脉内膜增生的影响。 方法： 将Wistar大鼠颈外静脉移植于腹主动脉,建立大鼠自体静脉移植模型,实验分为3组：假手术组、移植对照组和移植实验组。自术后第1 d起,对移植实验组大鼠经胃管灌注给予阿托伐他汀(5 mg·kg-1·d-1)处理。干预4周后取移植静脉组织标本,制备4 μm厚组织切片,行病理组织学观察分析移植静脉内膜增生情况,行免疫组化染色分析新生内膜细胞SMα-actin和PCNA的表达情况。 结果： 移植对照组和实验组移植静脉内皮下层SMα-actin染色阳性平滑肌细胞大量增生,导致静脉内膜显著增厚,血管管腔明显狭窄。新生内膜定量分析显示移植实验组移植静脉内膜增生受到明显抑制,其新生内膜面积及新生内膜/中膜面积比均显著低于对照组(P<0.01);并且实验组移植静脉新生内膜细胞PCNA标记指数显著低于对照组(P<0.01)。 结论： 阿托伐他汀通过抑制新生内膜平滑肌细胞的增殖能有效抑制自体移植静脉内膜增生的发生发展,在防治血管重建术后再狭窄方面显示出良好的应用前景。     

急性排斥移植肾组织嗜酸性粒细胞浸润及C4d沉积

目的：通过观察移植肾PTC C4d沉积和嗜酸性粒细胞浸润与AHR的关系,探讨两者之间的相关性及其在诊断急性体液排斥中的作用。方法：采用间接免疫荧光法检测移植肾组织C4d沉积。26例移植肾PTC C4d弥漫性强阳性染色患者为C4d阳性组,而30例移植肾PTC C4d阴性患者为对照组。光镜下记数移植肾组织嗜酸性粒细胞数。结果：（1）26例C4d阳性患者中经病理诊断为AHR为13例,AHR＋ACR为8例,ACR1为3例,ACR2为2例。30例C4d阴性患者中,AHR为1例,AHR＋ACR为2例,ACR1为21例,ACR2为6例。与C4d阴性组相比,C4d阳性组难治性排斥患者较多,常需进一步干预性措施,且较多的患者对抗排斥治疗无反应,移植肾失功率高（7/26）。（2）C4d阳性组移植肾浸润嗜酸性粒细胞数亦明显高于C4d阴性组,两组相比差异显著（P〈0.01）。C4d阳性无细胞性排斥组移植肾间质浸润嗜酸性粒细胞数与C4d阳性＋ACR组相比差异无显著性（P〉0.05）。C4d阳性ACR组移植肾间质浸润嗜酸性粒细胞数明显高于C4d阴性ACR组（P〈0.05）。结论：移植肾PTC C4d沉积与嗜酸性粒细胞浸润密切相关,两者在肾移植AHR诊断过程中起重要作用。     

Cold ischemia induces isograft arteriopathy, but does not augment allograft arteriopathy in non-immunosuppressed hosts

Prolonged cold ischemia has been suggested as a factor that will exacerbate later graft arterial disease (GAD), a major limiting factor for long-term transplant survival. We therefore examined the effects of cold ischemia on GAD as well as adhesion molecule and cytokine expression in murine cardiac grafts. Mild GAD developed in isografts undergoing 4-hour cold ischemia. Relative to control isografts, cold ischemia induced transiently enhanced endothelial expression of intercellular adhesion molecule-1 (ICAM-1) at 4 hours post-transplant. There was also transiently-augmented gene expression of interleukin (IL)-1beta, IL-6, and transforming growth factor-beta in these cold-ischemic isografts. By 3 days post-transplantation, however, there were no longer any differences between control and cold ischemic isografts. Cold ischemia did not significantly affect the final grade of either parenchymal rejection or GAD in long-term (4 to 12 weeks) major histocompatibility complex (MHC) I- or MHC II-mismatched allografts molecules transplanted without immunosuppression. At early time points after cold ischemia (4 to 24 hours), allografts mismatched for MHC I and/or MHC II showed enhanced expression of ICAM-1 and cytokines comparable to that seen in isografts. By day 7 post-transplant, both control and cold ischemia allografts showed comparable expression of cytokines and adhesion molecules. Although prolonged cold ischemia can initiate mild GAD in isografts by transiently enhancing antigen non-specific inflammatory responses, it does not significantly augment subsequent alloresponses.     

Early T cell response to allografts occurring prior to alloantigen priming up-regulates innate-mediated inflammation and graft necrosis

The early inflammatory response within organ allografts is initiated by ischemia/reperfusion (I/R) and promotes subsequent alloantigen-primed T cell recruitment into and rejection of the graft. Polymorphonuclear leukocyte (PMN)-mediated tissue damage is a primary component of the early inflammation in allograft rejection. We sought to compare and elucidate the mechanism of early PMN infiltration into cardiac isografts and allografts. Despite identical production of PMN attractant chemokines, PMN infiltration following reperfusion into syngeneic and allogeneic grafts was not equivalent. PMN infiltration into isografts peaked at 9 to 12 hours post-transplant and quickly resolved. In contrast, PMN infiltration into allografts continued to elevated levels, peaking at 24 hours post-reperfusion. This amplified PMN infiltration into allografts did not resolve until 72 hours post-reperfusion and was accompanied by marked parenchymal necrosis. This early innate inflammatory response was regulated by IFN-gamma-producing CD8+ T cells present in the recipient before detectable alloantigen T cell priming. Co-culture with CD62L(low) CD8+ T cells, but not CD62L(high) CD8+ or CD62L(low) CD4+ T cells, harvested from na?ve animals induced allogeneic endothelial cells to express IFN-gamma-dependent chemokines. These data demonstrate CD8+ T cell-mediated attack on the vascular endothelium of allografts within hours following organ reperfusion that amplifies innate immune-mediated intra-graft inflammation and necrosis.     

Carbon monoxide inhalation protects rat intestinal grafts from ischemia/reperfusion injury

Carbon monoxide (CO), a byproduct of heme catalysis by heme oxygenases, has been shown to exert anti-inflammatory effects. This study examines the cytoprotective efficacy of inhaled CO during intestinal cold ischemia/reperfusion injury associated with small intestinal transplantation. Orthotopic syngenic intestinal transplantation was performed in Lewis rats after 6 hours of cold preservation in University of Wisconsin solution. Three groups were examined: normal untreated controls, control intestinal transplant recipients kept in room air, and recipients exposed to CO (250 ppm) for 1 hour before and 24 hours after surgery. In air grafts, mRNA levels for interleukin-6, cyclooxygenase-2, intracellular adhesion molecule (ICAM-1), and inducible nitric oxide synthase rapidly increased after intestinal transplant. Histopathological analysis revealed severe mucosal erosion, villous congestion, and inflammatory infiltrates. CO effectively blocked an early up-regulation of these mediators, showed less severe histopathological changes, and resulted in significantly improved animal survival of 92% from 58% in air-treated controls. CO also significantly reduced mRNA for proapoptotic Bax, while it up-regulated anti-apoptotic Bcl-2. These changes in CO-treated grafts correlated with well-preserved CD31(+) vascular endothelial cells, less frequent apoptosis/necrosis in intestinal epithelial and capillary endothelial cells, and improved graft tissue blood circulation. Protective effects of CO in this study were mediated via soluble guanylyl cyclase, because 1H-(1,2,4)oxadiazole (4,3-alpha) quinoxaline-1-one (soluble guanylyl cyclase inhibitor) completely reversed the beneficial effect conferred by CO. Perioperative CO inhalation at a low concentration resulted in protection against ischemia/reperfusion injury to intestinal grafts with prolonged cold preservation.     

同基因造血干细胞移植延长同种异体小鼠皮肤移植物存活时间的实验研究

为了研究同基因造血干细胞移植诱导器官移植免疫耐受的可行性。建立小鼠异基因皮肤移植模型,术后2周给予FK506腹腔注射,3周起行全身照射及同基因骨髓移植,观察记录小鼠和移植物存活情况,以流式细胞检测受体GFP嵌合表达,混合淋巴细胞反应、迟发型超敏反应检测诱导耐受的特异性和效能。实验组小鼠移植物存活时间达(29.14±4.92)d,显著长于对照组(P<0.05);GFP在BMT后4周、6周嵌合程度达到82%、91%;实验组MLR、DTH结果与对照组差异显著,提示诱导耐受具有高度特异性和高效性。同基因造血干细胞移植联合免疫抑制剂治疗可以有效诱导小鼠皮肤移植的免疫耐受。     

Transplant arteriosclerosis in a rat aortic model.

Transplant arteriosclerosis (TA) has emerged as an obstacle to the long-term survival of transplanted organs, especially cardiac transplants. The animal models that have been used to study TA have not been fully characterized with regard to features such as the time course of cell proliferation and the sequence of cell types arriving in the developing intimal lesion. We present a model of TA based on a transplanted segment of abdominal aorta that helps address these questions. Two strains of rats (PVG x DA) underwent orthotopic aortic transplantation without immunosuppression and were killed at 14, 20, 40, and 60 days after transplantation. The within-strain control group displayed minimal evidence of cellular rejection with minimal to absent intimal lesions. In contrast, the allograft group showed a linearly increasing intimal lesion, up through 60 days after transplantation. The mechanism of intimal thickening was by an increase in cell number at the earlier time points with the later deposition of extracellular matrix. The early intimal lesion consisted mostly of mononuclear inflammatory cells (45%) with gradually increasing presence of smooth muscle cells (SMC) in the intima between 20 and 60 days. Conversely, the media showed gradual infiltration by macrophage-type cells with virtual loss of all SMC from the media by 40 days. The proliferative index showed a peak of 6% and 8% at 20 days in both the intima and media, respectively, and was preceded by the presence of macrophages. In fact, most of the proliferating cells at the earlier time points were either monocytes/macrophages, or were immediately adjacent to monocyte-/macrophage-rich regions. This straight artery segment model of transplant arteriosclerosis provides an easily quantifiable system in which the effects of different interventions (e.g., immunosuppressive regimens) can be tested.     

Treatment with mPEG-SPA improves the survival of corneal grafts in rats by immune camouflage

We investigated the immune camouflage effects of methoxy polyethylene glycol succinimidyl propionate (mPEG-SPA) on corneal antigens and explored a novel approach for reducing corneal antigenicity, thereby decreasing corneal graft rejection. Importantly, this approach did not alter normal local immunity. Corneal grafts were treated with mPEG-SPA 5KD or 20KD (3% W/V), which could shield major histocompatibility antigen class I molecules (RT1-A) of corneal grafts. Skin grafts of Wistar rats were transplanted to SD rats. Then the splenic lymphocytes were isolated from SD rats. Subsequently, the lymphocytes were co-cultured with autologous corneal grafts or untreated corneal grafts and PEGylated grafts treated with mPEG-SPA 5KD or 20KD obtained from the counterpart skin donors, which were used as autologous control, allogeneic control, mPEG-SPA 5KD group and mPEG-SPA 20KD group, respectively. Lymphocyte proliferation was lower in mPEG-SPA 5KD group and mPEG-SPA 20KD group than in the allogeneic control. SD rats with corneal neovascularisation were used as recipients for high-risk corneal transplantation and were randomly divided into four groups: autologous control, allogeneic control, mPEG-SPA 5KD group and mPEG-SPA 20KD group. The recipients received corneal grafts from Wistar rats. Corneal graft survival was prolonged and graft rejection was reduced in the mPEG-SPA 5KD group and the mPEG-SPA 20KD group compared to the allogeneic control. Thus, we think that mPEG-SPA could immunologically camouflage corneal antigens to prolong corneal grafts survival in high-risk transplantation.     

FTY720对小肠移植物中淋巴细胞及单核细胞浸润的影响

目的：研究FTY720对同种异体小鼠小肠移植排斥反应的作用及可能机制。方法：以C3H小鼠（H-2k）为供者，C57BL/6小鼠(H-2b）为受者，行异位小肠移植。分别建立FTY720治疗组、空白对照组及同系移植组，在移植后6 d与12 d进行组织学观测评定排斥分数，流式细胞术分析移植物肠系膜淋巴结（MLN）、派氏结（PP）、粘膜上皮细胞间淋巴组织（IEL）与固有层淋巴组织（LPL）中淋巴细胞中受者淋巴细胞及单核细胞浸润情况。结果：FTY720在移植后6 d可有效抑制排斥反应，但在移植后14 d，排斥反应仍可发生在空白对照组，移植后6 d移植物内受者淋巴细胞基本取代供者细胞；而在FTY720治疗组，受者淋巴细胞进入移植物的速度及数量明显减缓，包括CD4+与CD8+ T细胞，以及CD19+ B细胞。受者来源的γδT淋巴细胞也显著减少。FTY720对Gr1+CD11b+单核细胞系也有一定的抑制作用。结论：FTY720可通过减少受者淋巴细胞及单核细胞进入移植小肠，起到缓解排斥反应的作用。     

Early islets and mesenchyme from an injured adult pancreas improve syngeneic engraftments and islet graft function in diabetic rats

A decrease in mass of isografts and a decline in islet function are major challenges in islet transplantations. Despite this, transplantation of 84?h harvested pancreatic duct ligation (PDL) tissues have been shown to have the same functional ability to foetal pancreata, but there was only 40% success in reverting hyperglycaemia. We tested the potential of early islets with mesenchymal stromal cells (MSCs) to promote isogeneic grafts survival and to restore normoglycemia in diabetic rats, in comparison with late islets. Islets were isolated from injured adult pancreata of donor rats at 24?h post ligation either with MSCs (24?h islet/MSC+) or without MSCs (24?h islet/MSC-), and at 84?h without MSCs (84?h islet/MSC-). These cells were transplanted under the renal capsule of syngeneic STZ-diabetic recipient rats. The islet grafts were monitored using the BGLs of recipients and the immunohistomorphology of the grafts were analysed using anti-insulin and anti-Ki67 antibodies. The mean BGL in 24?h islet/MSC+ recipients was reduced over time toward the control value. The curves of the mean BGLs in the control islet/MSC- and the 24?h islet/MSC- recipients dropped significantly below the control normal glucose group’s levels to reach their nadirs on weeks 4 and 6, respectively. Both curves had a peak overshoot on week 9, with no statistical significant difference between them. Engrafted islets were evident in these recipients, lasted for 5 and 6 weeks and correspondingly survived failure. However, insulin+ cells were present in the isografts of all recipients; but, only isografts in the 24?h islet/MSC+ presented with a homogenous subcapsular beta cell mass. In addition, the tendency of 24?h islet/MSC- to restore normoglycaemia with its survival capacity was statistically highly significant compared to the 84 islet/MSC- recipients (80%; 20%; p?=?0.001). Transplantation of early islets with MSCs from injured adult pancreata prolongs islet graft survival and improves isograft function in diabetic rats. This novel observation requires much further exploration for its clinical application, but this model already provides hope for new sources of donor islets for transplantation.     

肺移植供肺获取100例：冷缺血时间>6 h及肺减容对预后的影响*

背景：肺移植过程中供肺获取的手术技巧、冷缺血时间的上限以及供肺与受者胸腔大小不匹配等问题的处理有待进一步研究。 目的：总结肺移植中供肺获取的手术技巧,探讨冷缺血时间和肺减容对受者移植后各种并发症以及生存率的影响。 方法：回顾分析100例供肺获取和101例受者的临床资料,根据供肺冷缺血时间所有受者分为冷缺血时间< 6 h组或> 6 h组;另根据移植中是否出现供肺与受者胸腔大小不匹配分为肺减容组和对照组,不匹配的均行不同方式肺减容。分析冷缺血时间>6 h和肺减容对肺移植患者预后的影响。 结果与结论：100例供肺获取和101例肺移植均成功,其中1供者的左右肺分别移植给2例受者,共完成101例肺移植。除供肺冷缺血时间>6 h组原发性移植物失功发生率要高于< 6 h组(P < 0.05)外,其他各指标差异均无显著性意义(P > 0.05);肺减容组与对照组各临床指标差异亦无显著性意义(P > 0.05)。提示严格的供者选择、恰当的供肺减容以及尽量缩短供肺冷缺血时间可以有效防止受者移植后各种并发症的发生,提高肺移植成功率,改善患者预后。 关键词：肺移植;脑死亡;供者选择;器官保存液;围手术期 doi:10.3969/j.issn.1673-8225.2012.05.018     

Mechanism of Immune Hyporesponsiveness Induced by Recipient-derived Immature Dendritic Cells in Rat Liver Transplantation

Objective: The use of donor-derived immature dendritic cells (imDC) has become a promising approach to induce immune tolerance or immune hyporesponsiveness. However, donor-derived imDC needs to be harvested for a few days and transfused into the recipient in 5-10 days before transplantation, which is practically impossible in a clinical setting where donor organs are mainly harvested from cadavers. Moreover, donor-derived imDC might be cleared by allogeneic reaction offsetting induced immune tolerance or immune hyporesponsiveness. In our study, we further explored the underlying mechanism of immune hyporesponsiveness induced by donor-antigen-unloaded recipient-derived imDC by transfusing these imDC into rats in 1 day before liver transplantation. This paper is to study the mechanism of immune hyporesponsiveness induced by donor-antigen-unloaded recipient-derived imDC and its protection of liver grafts in rats. Methods: 40 SD rats (donor) and 40 male Wistar rats (recipient) were randomly divided into 4 groups: control, cyclosporine A(CsA), mature DC (mDC), and imDC; with 10 SD rats and 10 Wistar rats for each group. Animal models of acute graft rejection were established with these rats. Corresponding treatments were given before or after transplantation. In the control group, Wistar rats received no treatment other than liver transplantation. In the CsA group, Wistar rats underwent liver transplantation plus CsA treatment (10 mg/kg·d) in the starting day 2 after transplantation. For the mDC group, recipient-derived mDC(1×106/rat) were infused intravenously via the dorsal vein of the penis to recipient rats. For the imDC group, imDC (1×106/rat) were injected into recipient rats via the dorsal vein of the penis. In each group, 5 recipients were executed at 10 days after transplantation; the remaining five recipients were kept for the observation of survival time. Blood samples were collected for the measurement of ALT and TBIL; IL-2, IFN-γ, IL-4 and IL-10 and levels were measured with double-antibody sandwich ELISA. Liver tissue was harvested for HE staining and the observation of histological features. Acute rejection was evaluated with Banff classification. Expression levels of Fas-L/Fas in the grafts were detected by immunohistochemical staining; and western blot was used to detect the expression level of Scurfin. Results: The median survival times (MST) of the liver allografts in the CsA and imDC group were significantly longer than those in the control or mDC group (P<0.05). The serum levels of ALT and TBIL in the control and mDC groups were significantly higher than those of the CsA or imDC group(P<0.05). Compared with the CsA and imDC group, the levels of IL-2 and IFN-γ were higher but the levels of IL-4 and IL-10 were lower than those of the control and mDC groups(P<0.01). Slight or no rejection reaction was found in the CsA and imDC groups (P<0.05). The expression level of Scurfin protein in CD4+ CD25+ T cells of the imDC group was significantly higher than that of three other groups(P<0.05). Conclusion: Donor-antigen-unloaded recipient-derived imDC is an effective treatment in inducing immune hyporesponsiveness by blocking indirect recognition in rat liver transplantation model. Survival span was significantly prolonged by its protective effect. The mechanism of immune hyporesponsiveness induced by imDC transfusion may involve the preprocesses of T cell apoptosis induction, immune tolerance or hyporesponsiveness in T cells, induction of the shift in THl/TH2 balance, selection activation of Th2 subset, or induction of regulatory T cell.