同种异体移植免疫耐受的进展

探索组织器官移植后的排斥反应,提高移植物的存活率是移植免疫研究者致力攻克的堡垒。20世纪90年代以来,随着器官移植术的广泛开展,人们对移植排斥反应的认识不断加深,对移植免疫耐受提出了新的研究思路和方法。目前普遍认为,解决异体移植排斥反应的关键在于诱导受体对供体的细胞、组织或器官产生免疫耐受,即受体免疫系统对移植物抗原产生特异性免疫无反应性。本文将对近年来阻断特异性免疫应答、诱导免疫偏离、主动免疫诱导同种移植耐受及建立受者体内嵌合体诱导移植耐受等主要方面的进展综述。     

同种异体肌腱移植的有关生物力学问题

腱是致密的、规则的胶原组织,它主要由平行排列的堆积成的胶原纤维组成,其它组成材料包括弹性纤维、网状纤维、蛋白多糖以及水等。胶原纤维使其具有一定的强度和刚度,弹性纤维使其具有在载荷下具有延伸的能力,而网状纤维提供容积。胶原组织附加成份为基质,是一种胶状材料,能减少纤维间的摩擦。而且研究表明,基质的完整性对腱的机械完整性是非常重要的,酶对于非胶原成份的消化作用可在很大范围内改变腱的力学特性。在运动过程中,腱主要承受张力,自身不会产生主动活动。大部分韧带（除项韧带、黄韧带外）具有和腱相似的物质结构     

大鼠同种异体甲状旁腺脑室内移植后血液供应和形态学的变化

目的：观察同种异体甲状旁腺脑室内移植后血管的再生和组织学变化。方法：Ｗistar大鼠 作为供体,ＳＤ大鼠作为受体,在立体定位下将同种异体甲状旁腺移植到ＳＤ大鼠侧脑室,利用组织学技术对甲状植后血液供应和形态学变化进行研究。结果：移植后５d脑内血管开始到达移植物边缘,以后在甲状旁腺实质内逐渐有血管出现,随着移植时间的延长移植物内和血管密度逐渐增加,以移植后４周接近正常;血管的配布与脑组织明显不同,ＨＥ染色发     

同种异体半月板移植的研究进展

膝关节半月板具有重要的生物力学功能，它是维持膝关节正常生理功能的重要组成部分，它可以增加关节软骨面之间的接触面积，减小关节面单位面积上的压力，其楔形结构可增加膝关节的稳定性，缓冲纵向压力。半月板切除后必然导致韧带松驰，关节不稳，软骨面磨损加快，加速膝关节退行性改变，为了避免这些并发症的发生，     

环氧乙烷处理同种异体皮质骨板移植组织学研究

目的 研究环氧乙烷处理同种异体皮质骨板移植组织学表现。方法 分别移植经过零下70℃深低温冷冻4周、零下70℃深低温冷冻4周+48℃环氧乙烷灭菌处理的山羊同种异体皮质骨板,对移植骨板以及周围软组织进行组织学检查。结果 术后3～6周深低温冷冻组移植骨板周围软组织少量炎性细胞浸润,环氧乙烷+深低温冷冻组移植骨板周围软组织较多炎性细胞浸润,但炎细胞浸润评分差别无统计学意义(P>0.05);术后6～24周两组移植骨板周围软组织炎性细胞浸润进一步减轻。深低温冷冻组和环氧乙烷+深低温冷冻组术后3周部分移植骨板原哈佛式管扩大,其内有少量间充质组织和新生血管;6周间充质细胞分化为破骨细胞和成骨细胞,破骨细胞使移植骨板哈佛式管进一步扩大以及出现骨吸收隙窝,在哈佛式管和骨吸收隙窝边缘出现成骨细胞贴附和新骨形成;12周移植骨板骨吸收隙窝缩小,成骨细胞和新骨形成增多,部分新骨改建形成板层骨:24周移植骨板基本完成吸收替代和改建塑形。两组移植骨板内无炎细胞浸润,组织学表现相似。结论 环氧乙烷灭菌同种异体皮质骨板移植周围软组织出现炎细胞浸润,不影响移植骨板爬行替代和内部改建塑形。     

同种异体卵巢移植术治疗两性畸形的探讨

本文首报同种异笨卵巢移植成功治疗男性假两性畸形患者1例，术后15个月B超动态观察移植卵巢血运正常，受体月经来潮，雌、孕激素测定值已趋正常，移植卵巢成活。阐述了手术方法、探讨了手术成功的关键，提示同种异体卵巢移植术给先天卵巢缺失患者带来希望，具有重要的临床价值。     

脱细胞处理的同种异体神经移植研究进展

周围神经损伤的修复是创伤外科难题之一,筛选促进神经再生理想的移植物,是解决这一难题的关键。近年来,在修复周围神经缺损研究中采用脱细胞处理的同种异体神经作为移植物,已取得促进神经再生的效果,展示了较好的应用前景。本文对脱细胞处理移植体的脱细胞处理方法,脱细胞处理后的细胞外基质所含的生物活性物质,以及这些物质的对促进神经再生的生物效应进行综述,以期为此种移植体的深入研究提供参考资料。     

带血管的同种异体关节移植进展

因剖伤、肿瘤或其它病因引起的关节缺损是医学中治疗的难题。近年来，国外学者进行了一系列的带血管同种异体关节移植实验研究，研究的重点仍然是克服移植排斥反应，综述如下：     

环氧乙烷处理同种异体皮质骨板移植组织学研究

目的研究环氧乙烷处理同种异体皮质骨板移植组织学表现.方法分别移植经过零下70℃深低温冷冻4周、零下70℃深低温冷冻4周+48℃环氧乙烷灭菌处理的山羊同种异体皮质骨板,对移植骨板以及周围软组织进行组织学检查.结果术后3～6周深低温冷冻组移植骨板周围软组织少量炎性细胞浸润,环氧乙烷+深低温冷冻组移植骨板周围软组织较多炎性细胞浸润,但炎细胞浸润评分差别无统计学意义(P＞0.05);术后6～24周两组移植骨板周围软组织炎性细胞浸润进一步减轻.深低温冷冻组和环氧乙烷+深低温冷冻组术后3周部分移植骨板原哈佛式管扩大,其内有少量间充质组织和新生血管;6周间充质细胞分化为破骨细胞和成骨细胞,破骨细胞使移植骨板哈佛式管进一步扩大以及出现骨吸收隙窝,在哈佛式管和骨吸收隙窝边缘出现成骨细胞贴附和新骨形成;12周移植骨板骨吸收隙窝缩小,成骨细胞和新骨形成增多,部分新骨改建形成板层骨;24周移植骨板基本完成吸收替代和改建塑形.两组移植骨板内无炎细胞浸润,组织学表现相似.结论环氧乙烷灭菌同种异体皮质骨板移植周围软组织出现炎细胞浸润,不影响移植骨板爬行替代和内部改建塑形.     

超抗原SEB在同种异体细胞移植小鼠中诱导的免疫耐受及其特征

目的 探讨超抗原葡萄球菌肠毒素B（SEB）体内诱导的免疫耐受性及其特征。方法 采用MHC不同的两种小鼠进行淋巴细胞移植。用流式细胞术和混合淋巴细胞培养技术，检测受体鼠T细胞亚群的变化，供体鼠H－2K^d分子在受体鼠体内表达的阳性率与免疫应答性。结果 （1）注射SEB可选择性地降低CD4^ T细胞和CD4^ T/H-2K^b 细胞的百分率，而不影响CD8^ T细胞的数量。在SEB注射的21d，抑制作用最强，其对CD4^ T细胞和CD4^ T/H-2K^b 细胞的抑制率分别是6.24%和23.38%。（2）在进行异源性MHC淋巴细胞移植时注射SEB，于移植细胞后21d，受体小鼠肝脏淋巴细胞上开始表达供体小鼠H－2K^d分子，至移植后40d，表达率达到高峰7.90%。与此同时，受体鼠外周淋巴细胞对供体鼠淋巴细胞的免疫应答能力也明显降低。结论 SEB能诱导小鼠产生免疫耐受，免疫耐受的形成与受体鼠内CD4^ T细胞克隆的明显减少有关。     

LPS诱导的内毒素血症小鼠及重症联合免疫缺陷小鼠模型炎症反应的比较

目的:比较脂多糖(LPS)诱导的内毒素血症BALB/c小鼠及重症联合免疫缺陷(SCID)小鼠炎症反应的差异。方法:建立LPS诱导的BALB/c小鼠和SCID小鼠内毒素血症模型,观察小鼠的存活率。分别于诱导前、诱导后3h、6h、12h,取小鼠的血清及诱导后12h小鼠的肝脏、肺脏,用全自动生化分析仪检测两种小鼠血清谷丙转氨酶(ALT)、谷草转氨酶(AST)、尿素氮(BUN)水平;HE染色评价肝脏、肺脏的炎症病理改变;用流式细胞术微球阵列法检测两种小鼠血清TNF-α、IFN-γ、IL-6及MCP-1的水平。结果:(1)LPS诱导内毒素血症后,SCID小鼠于12～24h均死亡(8/8),BALB/c小鼠仅1只死亡(1/8)。(2)LPS诱导后12h,BALB/c小鼠及SCID小鼠血清ALT、AST、BUN的水平均明显升高(P<0.05),SCID小鼠前两项均高于BALB/c小鼠(P<0.05),但BUN两种小鼠无显著差异。(3)肺脏,肝脏炎症盲法的病理评分,SCID小鼠均高于BALB/c小鼠(P<0.05)。(4)SCID小鼠和BALB/c小鼠LPS诱导后3h、6h、12h,血清TNF-α,IFN-γ的水平,诱导后12h,IL-6,MCP-1的水平均显著升高(P<0.05),SCID小鼠明显高于BALB/c小鼠(P<0.05)。结论:LPS刺激SCID小鼠后,可分泌过量的炎性细胞因子,导致更严重的内毒素血症和脏器损伤,是造成小鼠死亡的重要原因。结果提示,缺乏适应性免疫应答细胞调控的情况下,异常增强的固有免疫应答,可能是危及机体生命的重症全身炎症反应综合征发生的重要原因。     

Split tolerance between spleen and lymph node cells in severe combined immunodeficiency mice grafted with AKR fetal liver cells

Severe combined Immunodeficient (SCID) mice defective in stemcells for T and B cells appear to be an ideal host for constructionof chimeric mice. When bone marrow cells are used as a sourceof stem cells, however, host SCID mice do not always show sufficientreconstitutlon. In this study, fetal liver cells from AKR embryoswere transplanted into SCID mice without prior irradiation.This treatment induced full reconstltution of lymphopoiesisas evaluated by flow cytometry analysis and serum Ig production2 months after transplantation. Thus, fetal liver cells seemto be a better source for reconstitutlon of SCID mice than bonemarrow cells. Lymph node (LN) cells of these mice (FLT mice)had no proliferatlve or cytotoxlc activities against eitherhost-type (C.B-17) or donor-type (AKR) spleen cells. However,spleen cells from FLT mice exhibited marked proliferatlve andcytotoxlc activities against C.B-17 cells, with no activitiesagainst AKR cells. Spirt tolerance against C.B-17 cells In spleenand LN cells was not a transient phenomenon, since similar resultswere obtained from a cytotoxic T lymphocyte assay 4 months later.In spite of the strong host reactivity in vitro, aberrationof clonal deletion or development of a graft-versus-host diseasewas not seen in FLT mice. As IL-2 induced the host reactivityof LN cells in a mixed lymphocyte reaction, potentially host-reactiveT cells were present in LN but were rendered anerglc. Tolerancein FLT mice seems to be regulated by a peripheral mechanism.We supposed that the split tolerance in FLT mice was inducedby the different antigenicity between the spleen and LN.     

人骨髓造血细胞经腹腔内和尾静脉注射移植SCID鼠的研究

目的 :比较腹腔内与尾静脉注射对SCID鼠进行异种骨髓移植的体内植入能力及GVHD的发生情况 ,为异种骨髓移植构建银屑病动物模型奠定基础。方法 :密度梯度离心法分离正常人骨髓单个核细胞 (BMMNC) ,以 4× 10 7的剂量分别经尾静脉和腹腔注射移植于经γ射线预照射的SCID鼠 ,移植后观察GVHD反应及外周血白细胞恢复动力学 ,并采用流式细胞术检测小鼠外周血及骨髓中人源性CD4 5 + 细胞比例 ,观察嵌合状态。结果 :单纯尾静脉注射移植组 ,在移植后 2周即出现明显GVHD症状 ,12周仅存活 1例 ;尾静脉注射结合CsA +MTX处理组 ,个别小鼠出现轻度GVHD表现 ,12周存活率 80 % (8 10 ) ;而经腹腔内注射者移植后出现轻度GVHD症状 ,之后逐渐恢复正常 ,12周存活率 70 % (7 10 )。移植后外周血白细胞动力学恢复情况、外周血及骨髓中人CD4 5 + 细胞比例 ,尾静脉注射结合CsA +MTX处理者与经腹膜腔内注射者二组间比较无显著性差异。结论 :人骨髓造血细胞可以顺利地由SCID鼠腹腔归巢到骨髓造血组织 ,并能重建骨髓造血 ,腹腔内注射的移植方式不影响植入能力 ,既可达到骨髓移植的目的 ,又可减少GVHD的发生及反应强度     

Human T-cell lymphotropic virus type-I infection in the severe combined immunodeficiency mouse

Human T-cell lymphotropic virus type-I (HTLV-I) is the etiologic agent of HTLV-I-associated myelopathy/tropical spastic paraparesis (HAM/TSP) and adult T-cell leukemia (ATL). HAM/TSP and ATL occur infrequently among HTLV-I-infected individuals, and rarely develop in the same individual. To study host and viral factors involved in the induction, tissue tropism, as well as pathogenesis of HAM/TSP, peripheral blood lymphocytes (PBL) from 14 patients with HAM/TSP and from 9 controls were introduced into severe combined immunodeficiency (SCID) mice by intraperitoneal injection. Mice were followed for up to 26 weeks. Human IgG was produced from 2 to 14 weeks after reconstitution in all animals. Thirty-two of 44 mice (72%) showed circulating human antibody against the major viral protein products of HTLV-I. Analysis of viral sequences by polymerase chain reaction (PCR) demonstrated HTLV-I sequences in 21/38 (55%) brains and in 7/17 (41%) spinal cords from HTLV-I-hu SCID mice. No animal had clinical evidence of neurological impairment or pathological findings similar to those seen in HAM/TSP. Seven mice who received PBL from Epstein Barr virus (EBV)-seropositive patients developed an intraperitoneal lymphoma. In 2 mice an infiltration of brain by a lymphoblastic tumor of B/T cell type was observed. By PCR, all the tumors were EBV-positive; HTLV-I sequences were detected in 5 of them. Our study suggests that the HTLV-I-hu-SCID mouse provides a potentially valuable system for studying the production, kinetics, and pathogenicity of anti-HTLV-I antibody, and may help clarify the interaction of EBV and retroviruses in the development of disease. © 1996 Wiley-Liss, Inc.     

A severe combined immunodeficiency disease mouse model of human adenocarcinoma with lepidic-predominant growth

Severe combined immunodeficiency disease (SCID) mice with human lepidic adenocarcinoma were established by the intrabronchial implantation of fresh surgically resected specimens. Human pulmonary adenocarcinoma tissue from 16 different cases was transplanted into SCID mice, and SCID mouse tumors were established from four of these cases (25%). Among the four tumors, the tumor cells of two SCID mice showed replacement lepidic growth of mouse alveolar structures accompanied by multiple intrapulmonary lesions. Human lung carcinoma cell lines showing lepidic growth are rare and the xenograft models using the SCID mouse model developed in the current study will be useful for analyzing the growth and/or progression patterns and clinical behavior of lepidic adenocarcinoma, the major histological subtype of human carcinoma of the lung.     

Defective membrane function in a patient with severe combined immunodeficiency disease

We report a girl with severe combined immunodeficiency with functional impairment of both humoral and cellular immunity despite normal numbers of B and T lymphocytes. Immunologic studies revealed hypergammaglobulinaemia, absent migratory response by polymorphonuclear leucocytes to chemoattractants, and diminished lymphocyte proliferative responses to mitogens, antigens and allogeneic leucocytes. However, stimulation of the patient's mononuclear leucocytes with the calcium ionophore, A23187, resulted in a normal proliferative response. We therefore postulate a membrane defect as the basis for immunologic dysfunction in this child.     

Transfer of immune components from rabbit autoimmune cardiomyopathy into severe combined immunodeficiency (SCID) mice induces cardiomyopathic changes

Background: Growing evidence suggests that autoimmune mechanism plays an important role in the pathogenesis of cardiomyopathy. The purpose of this study was to investigate whether passive transfer of IgG and/or lymphocytes from rabbits with autoimmune cardiomyopathy is able to reproduce cardiomyopathic changes in severe combined immunodeficiency (SCID) mice.

Methods and results: SCID mice were injected intraperitoneally with IgG and/or peripheral blood lymphocytes (PBL) from either rabbits immunized with both β1-adrenoceptor peptide and M2-muscarinic receptor peptide (β1+M2 group) or rabbits with adjuvant (N group). Thirty five SCID mice were divided into seven groups; N-IgG, N-PBL, N-IgG &; PBL, (β1+M2)-IgG, (β1+M2)-PBL, (β1+M2)-IgG &; PBL and control groups. Heart weight in three (β1+M2) groups were significantly increased. All mice in three (β1+M2) groups showed high titer of rabbit anti-β1 adrenocepter autoantibodies, and 4 mice in the (β1+M2)-PBL group and 3 mice in the (β1+M2)-IgG &; PBL group showed a significant increase in titer of rabbit anti-M2-muscarinic receptor autoantibodies. Focal infiltration of inflammatory cells in the myocardium was observed in the (β1+M2)-IgG &; PBL group. In the (β1+M2)-PBL group and (β1+M2)-IgG &; PBL group, cardiomyocyte diameters were significantly increased. Some myocytes of the (β1+M2)-IgG &; PBL group exhibited intracellular edema, clumps of Z-band and increased numbers of mitochondria by using electron microscopy.

Conclusion: Transfer of IgG and PBL from rabbits immunized with combined β1 and M2 peptides was able to reproduce the early stage of cardiomyopathic changes in SCID mice     

Long-term follow-up in patients with severe combined immunodeficiency treated by bone marrow transplantation

Immune reconstitution was studied in 31 long-term surviving patients after bone marrow transplantation for severe combined immunodeficiency. Donors in 7 cases were HLA-identical and in 25 cases HLA-haploidentical family members, and in 13 of these latter cases cytoreductive conditioning had been used prior to transplantation. At a mean follow-up of 15 years after transplantation (range 10 to 22 years), T cell numbers and functions had remained stable and within normal limits in the majority of patients. Marked variability however was observed with regard to reconstitution of B cell immunity. Furthermore numbers of circulating naïve CD4+ T cells were variable and markedly diminished in a substantial proportion of patients at recent evaluations. Normal B cell immunity and persistently normal naïve T cell numbers were strongly correlated with the continued detection of donor type CD34+ precursor cells in the patients marrow, which were absent in non conditioned patients. These findings indicate that stable donor precursor cell engraftment in the marrow may be of relevance for complete and stable long-term immune reconstitution in transplanted SCID patients.     

Presence of intestinal intraepithelial lymphocytes in mice with severe combined immunodeficiency disease.

The murine intestinal epithelium contains a heterogeneous population of intraepithelial leukocytes (IEL) most of which are granulated, Thy-1-CD5-CD8+. In order to assess the lineage relationship of this subgroup of IEL to peripheral T cells, we examined IEL in mice with the severe combined immunodeficiency (scid/scid) mutation, which lack T and B cells in peripheral lymphoid tissues. Electron and light microscopy showed that the intestine from scid/scid mice had granulated IEL similar to IEL in normal C.B-17 mice. Flow cytometry of isolated IEL stained with monoclonal antibodies against Thy-1, CD3, CD4, CD5 and CD8 showed that scid/scid mice IEL contained cells with the Thy-1-CD4-CD5-CD8+ phenotype. Immunohistochemical staining of IEL in tissue sections with antibodies to Thy-1 and CD8 confirmed that the Thy-1-CD8+ cells were in the intestinal epithelium. These scid/scid IEL also lacked CD3 expression and mRNA for the V gamma 7 V region gene of the gamma T cell receptor. We conclude that scid/scid mice contain precursors for IEL that can differentiate into a granulated Thy-1-CD5-CD8+ IEL in the intestine. The absence of CD8+ peripheral T cells in these mice suggests that these IEL differ from classical T cells in their ability to differentiate and express CD8 and do not require T cell receptor expression for their localization to the intestine.