人胸腺和脐血造血干/祖细胞联合移植对裸鼠细胞免疫功能的影响

背景：T细胞在抗感染、抗肿瘤和免疫调节等中起重要作用,但T细胞分化发育机制尚未完全阐明。 目的：观察人胸腺、人脐血联合移植后裸鼠体内T细胞分布及免疫功能的重建。 方法：Balb/c nu/nu裸鼠30 只,随机分为2组：实验组肾被膜下移植胸腺组织,2周后将新鲜分离的脐血CD34+细胞悬液经小鼠静脉输入,对照组不经胸腺移植直接给予CD34⁺细胞移植,两组小鼠饲养至60 d时检测免疫功能。 结果与结论：人胸腺在裸鼠肾被膜下存活并且表达CD3、HLA-DR分子,胸腺与CD34⁺细胞联合移植组小鼠脾脏可见点块状分布的CD3⁺细胞。实验组CD3⁺细胞、CD4⁺细胞、CD8⁺细胞及CD4⁺CD25⁺细胞比例均显著高于对照组。实验组裸鼠对移植人胃癌BGC823细胞有排斥作用,而对照组没有。结果显示胸腺和CD34⁺细胞联合移植能使裸鼠获得T细胞介导的细胞免疫功能,具有抗肿瘤能力。     

重症肌无力患者胸腺Foxp3及其调控基因表达的研究

目的 研究Foxp3及相关基因在重症肌无力(MG)胸腺组织中的表达,探讨其在MG发病中的作用及意义.方法 采用免疫组织化学、Western blot以及RT-PCR技术,检测MG患者及正常对照胸腺组织中Foxp3、Smad3、Smad7、TCF-β、IFN-у的表达差异.结果 MG胸腺Foxp3蛋白及mRNA表达均显著低于正常,MGFA Ⅱ、Ⅲ型(全身型)患者胸腺Foxp3表达显著低于Ⅰ型(眼肌型);而Ⅲ型(中度全身型)则显著低于Ⅱ型(轻度全身型)(P＜0.05);MG胸腺内TGF-t3 mRNA水平及其信使Smad3/Smad7比值显著降低,与Foxp3表达呈显著正相关(P＜0.01,r=0.871).结论 F0xp3在MG发病中可能起着重要作用,TGF-β表达异常可能系MG胸腺Foxp3下调的原因之一.     

带血管蒂胎胸腺移植治疗重症肌无力的临床护理

重症肌无力是累及神经肌肉接头处突触后膜上乙酰胆碱受体的自身免疫性疾病,临床特征为部分或全身横纹肌异常地容易疲劳。胸腺瘤合并重症肌无力(MG)治疗较为棘手,是否手术治疗仍有争论,除肿瘤本身具有浸润性外,MG自身免疫变化加重了治疗的复杂性。我科于1998年11月至2000年4月应用胸腺切除并带血管蒂胎胸腺移植治疗MG 5例,取得良好效果。现将临床护理介绍如下。     

裸鼠皮下人肝癌移植瘤模型的建立

目的建立裸鼠皮下肝癌移植瘤模型。方法BLBA/c裸鼠颈背部皮下注射人肝癌SMMC-7721细胞悬液5×106个.0.2m l-1.只-1,观察肿瘤生长情况,45d处死。瘤组织作病理及电镜检查;取裸鼠周围血作甲胎蛋白(AFP)的检测;用免疫组化法检测肿瘤微血管密度(MVD)。结果该模型具有类似人原发性肝癌的形态学特征。结论成功建立了人肝癌裸鼠皮下移植瘤模型。     

人绒毛膜癌裸鼠原位移植模型的建立

目的建立人绒毛膜癌裸鼠原位移植瘤模型。方法培养人绒毛膜癌细胞系JAR,制备JAR单细胞悬液,给5只8周龄BALB/c裸鼠经皮下注射建立皮下移植瘤模型。待裸鼠皮下成瘤后,无菌条件下取瘤组织并切成1 mm^3组织块,通过手术方式植入10只10周龄BALB/c裸鼠子宫腔内,裸鼠濒死状时4%水合氯醛(10 g/kg)腹腔注射麻醉处死,观察子宫成瘤及腹腔转移情况。解剖取子宫原位移植瘤、腹腔内转移瘤、腹腔淋巴结及其他脏器组织标本,通过组织病理学检查进行鉴定。结果10只BALB/c裸鼠中共有7只裸鼠子宫内可见移植瘤肿块形成,其中2只可同时观察到子宫移植瘤和腹膜转移瘤。在病理学形态和结构上,皮下移植瘤模型、原位移植模型和腹膜转移瘤的瘤细胞与人绒毛膜癌细胞系JAR一致。结论成功建立人绒毛膜癌JAR细胞的BALB/c裸鼠原位移植瘤模型。     

脐血体外同时扩增T、NK及干祖细胞移植治疗BALB/c小鼠白血病

目的观察体外同时扩增T、NK及干祖细胞脐血用于移植治疗BALB/c小鼠白血病效果.方法在不同的细胞因子组合作用下定向扩增脐血干祖细胞及T、NK免疫细胞.扩增7天后,5 × 106个/只脐血细胞经尾静脉接种X射线照射的白血病小鼠,观察各组小鼠存活时间及检查存活证据及微小残留白血病细胞.结果1.细胞因子SCF,IL-3,IL-6,IL-7,IL-2组合能显著扩增脐血中的CD34 、CD3 T、NK细胞.2.尾静脉接种2×106个/只K562产生可移植性白血病BALB/c裸鼠.3.BALB/c白血病小鼠移植6周后,实验组共存活鼠12只.而未移植者在60天内死于肿瘤.4.流式细胞分析移植30天后小鼠外周血中人CD3 细胞从最低新鲜脐血移植组(0.48±0.40)%,最高SCF IL-3,6,7组中为(3.01±1.25)%.RT-PCR 检测发现,在12只扩增后移植存活6周小鼠中,检测不到bcr/abl 基因.在3只新鲜脐血移植存活6周的小鼠中,1只呈现阳性,说明移植取得了造血与免疫重建.所有脐血移植小鼠均未出现明显临床GVHD 症状.结论这种扩增后含一定水平T、NK免疫细胞的脐血能重建可移植性BALB/c 白血病小鼠的造血和免疫.     

人前列腺癌裸鼠皮下移植瘤模型的建立

目的 建立人前列腺癌裸鼠皮下移植瘤模型.方法 采用人前列腺癌细胞株PC-3细胞接种于裸鼠的颈背部皮下,计算成瘤潜伏期、成瘤百分率,观察移植瘤大体生长情况,绘制生长曲线,并对移植瘤进行病理鉴定.结果 采用人前列腺癌细胞株PC-3细胞皮下接种方式建立移植瘤的平均成瘤潜伏期为24天,成瘤百分率为100％,瘤体积倍增时间为10天左右,移植瘤的形态和功能特性与原发肿瘤基本相似.结论 本动物模型的建立可为前列腺癌的放射免疫显像以及放射免疫治疗提供一个有价值的实验平台.     

Toll样受体在重症肌无力患者胸腺组织中的表达及其临床意义

目的 研究Toll样受体(Toll-like receptor,TLRs)在重症肌无力(myasthenia gravis,MG)患者胸腺组织中的表达,分析其与MG发生、发展的关系.方法 收集我科2007年7月至2008年2月手术治疗的36例MG患者胸腺标本,分为胸腺瘤组、瘤旁胸腺组、非瘤MG胸腺组,以无MG的正常胸腺21例为对照(正常胸腺组),采用逆转录-PCR技术,检测TLR2、TLR3、TLR4在胸腺组织中的mRNA转录表达水平,进一步采用实时定量逆转录-PCR检测TLR4 mRNA转录表达水平以及与MG临床特点间的关系.结果 逆转录-PCR结果显示,TLR2 mRNA和TLR3 mRNA在4组之间的差别没有统计学意义,TLR4 mRNA的表达在4组之间的差别有统计学意义.进一步的实时定量逆转录.PCR检测TLR4 mRNA转录表达的结果显示,瘤旁胸腺组的TLR4 mRNA的表达比胸腺瘤组有明显的增加(0.8214±0.1019 vs 0.7101±0.0916,P=0.005),非瘤MG胸腺组TLR4 mRNA的表达量比正常胸腺组明显增加(0.8544±0.1200 vs 0.6851±0.1524,P=0.018),瘤旁胸腺组和非瘤MG胸腺组TLR4 mRNA的表达量之间的差别没有统计学意义,且都比正常胸腺组明显增加;TLR4 mRNA的表达与患者的Osserman分型呈正相关(R=0.609;P=0.004).结论 TLR4异常表达可能在MG发病中有重要作用,MG合并胸腺瘤患者瘤旁胸腺组织中TLR4的表达状态对胸腺瘤患者是否并发MG可能有重要影响.     

肝原位移植瘤裸鼠模型的建立及活体荧光成像检测

目的 建立能够通过活体荧光成像系统实时监测肿瘤进展的肝原位移植瘤裸鼠模型.方法 重组质粒pcDNA3.1-Luc转染细胞构建稳定表达荧光素酶的PLC/PRF/5肝癌细胞株,将该细胞注入裸鼠肝脏实质内,应用活体成像技术动态监测肿瘤进展情况,解剖荧光信号阳性裸鼠观察肿瘤组织生长情况.免疫荧光检测肿瘤组织中HBsAg表达.结果 对裸鼠肝原位移植瘤应用活体荧光系统成像,在肿瘤细胞注射部位检测到荧光信号,解剖动物后可在肝脏组织中观察到异质细胞团块.免疫荧光证实移植瘤中有HBsAg表达.结论 肝脏原位移植瘤裸鼠模型建立成功,为抗肝癌药物的研发提供了工具.     

重症肌无力患者胸腺内microRNA-29表达水平的探究

目的 检测重症肌无力(myasthenia gravis,MG)患者胸腺组织中microRNA-29的表达水平并探讨其与MG发病的相关性.方法 22例经手术治疗的MG患者胸腺组织作为实验组,22例经手术治疗的非MG伴胸腺异常患者胸腺组织作为对照组.通过实时荧光定量PCR(quantitative real-time PCR,qRT-PCR)的方法检测实验组及对照组胸腺组织中microRNA-29表达水平,采用秩和检验(Mann-Whitney U test)分析实验组与对照组中microRNA-29表达水平.采用Spearman秩相关分析实验组胸腺中microRNA-29表达水平与定量重症肌无力(quantitative myasthenia gravis score,QMG)之间的相关性.结果 MG患者胸腺组织中microRNA-29表达水平较对照组显著增高(P=0.032);依据MG患者性别、年龄、临床特点、胸腺病理结果将实验组分成不同临床亚组,microRNA-29在各组间表达差异无统计学意义(P值分别为0.614、0.471、0.267、0.329);microRNA-29表达水平与QMG呈显著正相关性(r=0.689,P=0.000a).结论 microRNA-29在MG患者胸腺组织中表达增高,其表达水平与肌无力严重程度呈正相关,而与患者性别、年龄、临床类型、胸腺病理结果无明显关联.     

The immunohistology of the thymus in myasthenia gravis.

We have investigated cell subpopulations in frozen sections of thymus tissue obtained from myasthenic (MG) and control subjects. With the use of an avidin-biotin immunoperoxidase system with monoclonal antibodies, the following cell surface antigens were studied on frozen sections (12 MG and 3 control thymus); T11, T4, T6, T8, IgM, IgD, and Ia. The pattern of T cell phenotypes in MG thymus is similar to that of normal control thymus when examined by immunohistologic techniques. MG cortical thymocytes are virtually all T11+, T4+, T8+, and T6+. In the medulla, at least 45% of thymocytes are T11+, with T4+ cells predominating over T8+ cells. Approximately 10% of medullary thymocytes are T6+. Scattered medullary cells expressing surface IgM and IgD are identified in both MG and normal thymuses. However, unlike the normal thymus, the MG thymus has numerous secondary follicles containing IgM- and IgD-bearing cells. This finding supports the hypothesis that the MG thymus microenvironment is aberrant. The Ia antigen is found in similar tissue section localization patterns in MG and control thymus. Ultramicroscopic studies show the Ia antigen predominantly on epithelial and interdigitating dendritic cells. By immunoperoxidase techniques, numerous keratin-positive cells are demonstrated in MG and control thymus. This suggests that thymic epithelial cells, like epithelial cells elsewhere, contain keratin. Because these data differ in degree from our previous findings in suspensions of MG thymocytes, this study emphasizes the importance of examining tissue sections as well as cell suspensions when one is studying lymphocyte surface markers.     

TNBS诱导的BALB/c小鼠炎症性肠病模型建立的影响因素

目的建立2,4,6-三硝基苯磺酸（TNBS）诱导的BALB/c小鼠炎症性肠病（IBD）模型,探讨其影响因素。方法将48只BALB/c小鼠随机分为8组：乙醇非夹闭对照组、乙醇夹闭对照组、低剂量非夹闭组、低剂量夹闭组、中剂量非夹闭组、中剂量夹闭组、高剂量非夹闭组、高剂量夹闭组,每组6只。各组分别用相应试剂灌肠造模,利用DAI评分及Wallace评分并结合一般情况评价模型。结果一般情况显示夹闭各组死亡小鼠均有肠梗阻现象,非夹闭组死亡小鼠未见肠梗阻现象;非夹闭各组体重低于乙醇非夹闭对照组（P〈0.01）;中剂量夹闭组和高剂量夹闭组体重低于乙醇夹闭对照组（P〈0.01）;高剂量夹闭组体重低于高剂量非夹闭组（P〈0.01）。疾病模型评价显示中剂量非夹闭组和高剂量非夹闭组第7天DAI评分及Wallace评分均高于乙醇非夹闭对照组（P〈0.01）,中剂量夹闭组和高剂量夹闭组第7天DAI评分及Wallace评分均高于乙醇夹闭对照组（P〈0.01）;中剂量夹闭组第7天DAI评分高于中剂量非夹闭组（P〈0.05）;中剂量夹闭组和高剂量夹闭组Wallace评分高于同等剂量的非夹闭组（P〈0.01）;中剂量夹闭组Wallace镜下评分高于中剂量非夹闭组（P〈0.01）。结论 TNBS诱导BALB/c小鼠IBD模型过程中,在造模试剂注入结肠后不宜夹闭肛门。同时,相对于大鼠,小鼠造模所用的TNBS剂量略高。     

Immunoglobulin synthesis in vitro by human thymus: comparison of myasthenia gravis and normal thymus

Immunoglobulin synthesis measured in incubated thymus tissue by the incorporation of [¹⁴C]amino acids has been studied in four thymus glands from patients with myasthenia gravis and in eight normal thymus glands from patients undergoing open heart surgery. Parallel studies have been carried out with one normal human spleen and two lymph nodes.     

The development of the thymus in the nude mouse

The developing thymus of nude mouse embryos (derived from homozygous, nu/nu x nu/nu, matings) has been examined from 13 days' gestation onwards for the presence of large basophilic stem cells or their lymphoid progeny. No trace of either stem cells or lymphocytes has been found at any stage, indicating that from the earliest stages of thymic development lymphopoiesis is defective. However, histological evidence alone is not sufficient to rule out the possibility that small numbers of lymphocytes may be present in the nude thymus. Recent evidence that nude mice born of heterozygous (nu/+) females possess some T lymphocytes and "T lineage" cells is discussed in relation to these findings. A series of morphological changes have been defined within the epithelial component of the developing nude thymus, further analysis of which may help to determine the nature of the thymic defect.     

The effect of CD3-specific monoclonal antibody on treating experimental autoimmune myasthenia gravis

CD3-specific monoclonal antibody was the first one used for clinical practice in field of transplantation. Recently, renewed interests have elicited in its capacity to prevent autoimmune diabetes by inducing immune tolerance. In this study, we tested whether this antibody can also be used to treat another kind of autoimmune disease myasthenia gravis （MG） and explored the possible mechanisms. MG is caused by an autoimmune damage mediated by antibody- and complement-mediated destruction of AChR at the neuromuscular junction. We found that administration of CD3-specific antibody （Fab）2 to an animal model with experimental autoimmune myasthenia gravis （EAMG） （B6 mice received 3 times of AChR/CFA immunization） could not significantly improve the clinical signs and clinical score. When the possible mechanisms were tested, we found that CD3 antibody treatment slightly down-regulated the T-cell response to AChR, modestly up-regulation the muscle strength. And no significant difference in the titers of IgG2b was found between CD3 antibody treated and control groups. These data indicated that CD3-specific antibody was not suitable for treating MG, an antibody- and complementmediated autoimmune disease, after this disease has been established. The role of CD3-specific antibody in treating this kind of disease remains to be determined. Cellular ＆ Molecular Immunology. 2005;2（6）：461-465.     

Airway inflammation and bronchial remodelling in toluene diisocyanate-exposed BALB/c mouse model

Toluene diisocyanate (TDI), a highly reactive industrial chemical, is one of the leading causes of occupation-related asthma in industrialized countries. The pathogenesis of TDI-induced asthma, however, remains not fully understood, in part due to lack of appropriate animal models. Twenty five female BALB/c mice (age: 8 weeks) were randomly divided into 5 groups: Ovabumin (OVA); OVA peptide amino acid residues No. 323-339 (Pep); TDI; alum and physiological saline. Mice were intraperitoneally injected with 25 microg OVA or pep absorbed on 300 microg alum, 300 microg alum or saline on days 0, 7 and 14. For the TDI group, mice were sensitized subcutaneously with 20 microl neat TDI on day 0; 20 microl of TDI in olive oil (1:10) on days 7 and 14; on days 21-23. Then each group was challenged intranasally with 20 microl of 1% OVA, 1% Pep, 1% TDI, 10% alum and saline respectively. On day 28, mice were killed under pentothal anesthesia. The results demonstrated that neutrophil-dominant inflammation with a few eosinophil infiltration occurred in the peri-bronchial and peri-vascular regions of the lungs. This was accompanied by hyperplasia/hypertrophy of cells lining the airways and mucus production as shown by HE staining. Positive immunohistochemical MBP staining in parenchyma was also shown. Th2 cytokine IL-4 and IgE production were significant increased 5 days after last challenge while IFN-gamma level was below the detection limit. Conclusion: the clear elevation of IL-4 and IgE could allow to conclude a possible Th2-like dominated allergic response in TDI-exposed BALB/c mouse model.     

B- and T-cell activation in the thymus of patients with myasthenia gravis

The activation state of thymic T and B lymphocytes was phenotypically and functionally explored in patients with Myasthenia Gravis (MG). We detected no phenotypic signs of activation in fresh total thymic lymphocyte suspensions (CD25 expression) while functional signs of activation were reflected by a significantly higher sensitivity to recombinant IL-2 (rIL-2) without any previous stimulation in MG patients as compared to controls. The response to rIL-2 was time-and dose-dependent, was inhibited by a blocking anti-IL-2 receptor antibody, and was associated to an increase of CD25+ T cells. Thymic B-cell populations purified after T cell and macrophage depletion, expressed at variable levels activation markers such as the transferrin receptor, the CD25, 4F2, CD23 and B8.7 Ag, indicating that a marked proportion of them are activated. Moreover, these B-cell populations were spontaneously sensitive to BCGF-12-kD and to a lesser extent to rIL-2, demonstrating that they also exhibit functional signs of activation. The largest proportion of activated B cells and the most intense response to BCGF-12-kD was found in patients presenting the highest anti-acetylcholine receptor (AChR) titers. Our data confirm the hyperactivity of the thymus gland in MG, reflected by the presence of T and B cells with functional signs of pre-activation. These cells could conceivably be located in lymphoid follicles and may represent autoreactive cells involved in the autoimmune process. Whether they are sensitized to AChR remains to be investigated.