自体角朊细胞引起Th1向Th2极化抑制同种异体免疫应答

我们已有的工作揭示 ,在混合皮肤移植的体外模型MELC中 ,自体角朊细胞可通过间接递呈同种异体抗原诱导免疫抑制。本文在此基础上 ,进一步分析其中Th1和Th2相关细胞因子含量的变化。结果发现 :(1)向MELC引入自体角朊细胞后约 32h ,原同种异体应答中出现的IFN γ和IL 2分泌格局开始让位于IL 4和IL 10 ,6 4h后IFN γ和IL 2完全消失 ,表明发生了淋巴细胞Th1向Th2亚群的极化 ;(2 )单抗封闭试验表明 ,IL 10在其中起关键作用 ;(3)经自体和异体角朊细胞调变过的淋巴细胞对MELR的作用相反 ,前者抑制 ,后者促进。这是首次从T亚群相互作用上探索并揭示混合皮肤移植引起局部免疫耐受的机制。     

自体角朊细胞抑制混合表皮淋巴细胞反应的研究

本文应用混合表皮淋巴细胞反应实验体系, 在体外模拟混合皮肤移植中的自体皮岛效应。结果发现： 自体表皮细胞能以剂量依赖形式抑制自体淋巴细胞对异体表皮细胞的同种异体增殖反应。抗原递呈抑制物氯喹可恢复由自体表皮细胞诱发的抑制。提示后者参与对同种异体抗原的间接递呈。进一步分析表皮中两种抗原递呈细胞的作用, 发现真正参与诱导抑制的是角朊细胞而不是表皮中的朗罕细胞。     

混合表皮淋巴细胞培养体系中IL—10表达在诱导免疫抑制中的作用

在前期对混合皮肤移植诱导局部耐受的免疫学机理研究中，我们发现将自体角朊细胞引入已建立的MELC体系可以诱导免疫抑制。平行工作也证实自体角朊细胞的引入可以使体系内的细胞因子格局发生从Th1向Th2的转变。我们用针对IL－10的单抗对自体角朊细胞在MELC体系中所诱导的免疫抑制进行封闭，以证实IL－10在角朊细胞所诱导的免疫抑制中的作用。进而我们将混合培养体系中的各细胞组份分离，证实在MELC体系中IL－10 mRNA主要来源于自体角朊细胞。     

TLSFJM在体内对同种异体抗原诱导的小鼠T细胞增殖和杀伤细胞分化的影响

目的：探讨JM急性T淋巴细胞白血病细胞分泌的抑制因子(TLSJM)对BALB／C小鼠胸腺发育的影响及其在体内对同种异体抗原诱导的小鼠辅助性T细胞(Th)增殖及杀伤性T细胞(CTL)分化的影响。方法：建立小鼠同种异基因型肿瘤排斥模型，实验小鼠腹腔注射含TLSFJM的JM细胞培养上清，对照小鼠注射RPMI1640。无菌取小鼠脾脏细胞，分别以^3H-TdR掺入法和^51Cr释放法检测T细胞增殖和CTL的分化。结果：①TLSFJM明显抑制多克隆刺激剂PHA联合IL-2诱导的小鼠胸腺细胞增殖；②体内注射TLSFJM明显抑制多克隆刺激剂PHA联合IL-2诱导的小鼠T细胞活化、增殖；③TLSFJM在体内能有效抑制同种异体抗原诱导的小鼠T细胞增殖；④TLSFJM在体内能有效抑制同种异体抗原诱导的小鼠CTL分化。结论：TLSFJM在体内能有效抑制同种异体抗原诱导的小鼠T细胞增殖和小鼠CTL分化。     

自体角质形成细胞在混合皮肤移植中诱导免疫抑制

目的 探索混合皮肤移植中,自体皮岛诱发移植免疫耐受的免疫机制,方法 在体外建立混合表皮淋巴细胞（MELC）培养体系,以反映移植受者对皮肤移植物的免疫排斥反应,同时,将自体表皮细胞引入已建立的混合表皮淋巴细胞培养体系,以模仿混合皮肤移植中的自体皮岛效应,并分析发挥抑制效应的细胞来源,结果 自体角质形成细胞可抑制淋巴细胞对同种异体抗原的增殖,结论 自体皮岛中的角质形成细胞参与对同种异体抗原的的呈而诱导移植物耐受。     

B7-H1协同刺激淋巴细胞增殖并诱导产生抑制性T细胞

目的：探讨B7-H1分子在抗原诱导的免疫反应中的作用。方法：在可溶性抗原PPD诱导淋巴细胞增殖体系中,加入中和抗体检测B7-H1的协同刺激作用。转染表达B7-H1的ECV304细胞,观测其对PPD诱导的淋巴细胞增殖、细胞因子分泌及淋巴细胞亚群比例的影响。将刺激后的淋巴细胞过继至自体或同种异体增殖体系中,检测其功能。结果：抗B7-H1中和抗体可降低PPD诱导的淋巴细胞增殖反应和细胞因子分泌;转染B7-H1的ECV304细胞可协同刺激抗原诱导的淋巴细胞增殖,促进细胞因子IL-10的表达,并改变T细胞亚群分布,增加CD4^＋T细胞亚群比例;自体或同种异体过继实验显示,B7-H1刺激后的淋巴细胞具有显著的免疫抑制功能。结论：B7-H1分子可协同刺激淋巴细胞增殖并诱导产生具有免疫抑制功能的T细胞亚群。     

108 Th细胞因子在移植免疫中的研究新进展

Th细胞是T细胞的一种重要的细胞亚群，能分泌多种细胞因子，调节机体的免疫应答，在移植免疫中发挥重要作用。根据Th细胞分泌细胞因子种类的不同，可分为Th0、Th1、Th2、Th3 4个细胞亚群。Th0细胞被认为是其它亚群的前体细胞，在一定条件下可分化为Th1、Th2、Th3细胞。Th1细胞主要分泌IL-2、IFN-γ、TNF-α，它主要介导细胞免疫应答。Th2细胞主要产生IL-4、IL-5、IL-6、IL-9、IL-10、IL-13，它主要介导体液免疫，而近来其在免疫诱导与免疫耐受中的作用正在被人们逐渐所认识。Th3细胞主要分泌高水平的TGF-β和IL-1RA，抑制免疫系统功能。本文就这些细胞因子在器官移植排斥反应和诱导免疫耐受方面发挥的重要作用做一综述。     

CTLA4-Ig基因修饰的树突状细胞体外对Th1/Th2平衡的影响

目的:探讨细胞毒性T淋巴细胞相关抗原4免疫球蛋白(CTLA4 Ig)基因修饰的树突状细胞(CTLA4 Ig-DCs)体外对Th1/Th2平衡的影响。方法:通过腺病毒载体将目的基因(CTLA4 Ig)转染至小鼠骨髓来源的树突状细胞(DC)。采用流式细胞术(FCM)检测DC表面分子和胞内CTLA4 Ig的表达;采用混合淋巴细胞反应检测DC刺激同种异体T细胞的能力,ELISA法检测DC抗原提呈反应中Th1和Th2类细胞因子IFN-γ和IL-4分泌水平。结果:CTLA4 Ig基因成功转染至DC,转染率约为80%,制备的CTLA4 Ig-DCs稳定表达CTLA4Ig,表面分子CD86呈现低表达;CTLA4 Ig-DCs可有效抑制T细胞增殖,降低抗原提呈反应上清中IFN-γ和IL-4的分泌,并增加IFN-γ/IL-4比值。结论:通过腺病毒将CTLA4 Ig转染DC并且高效表达,可有效降低DC表面CD86分子,抑制同种异体T细胞反应,并能影响体外Th1/Th2水平。     

IL-12对BALB/c小鼠Th17细胞的分化的影响

目的: 观察细胞因子IL-12对Th17细胞分化的影响.方法: 小鼠脾淋巴细胞经抗CD3单克隆抗体(mAb)和不同浓度的重组小鼠IL-12刺激, 3 d后使用ELISA方法观察培养物上清液中IL-17的产生情况.并使用细胞内细胞因子染色的方法, 通过流式细胞术观察CD3 mAb和重组小鼠IL-12刺激对Th1和Th17细胞分化的影响.结果: Th17细胞不分泌IFN-γ、 IL-5、 IL-10等细胞因子, 不表达Foxp3, 是一个独立的细胞亚群.不同浓度的重组小鼠IL-12可以诱导抗CD3 mAb 的T细胞分泌IFN-γ, 并向Th1细胞方向分化.同时, IL-12可以抑制活化的T细胞分泌IL-17, 抑制T细胞向Th17细胞分化.结论: IL-12可以抑制Th17细胞的分化.     

免疫学

0502026 人OX40L在BL-21大肠杆菌中的表达和生物学功能研究；0502027 骨髓间充质干细胞通过分泌TGF-β1抑制T细胞的增殖；0502028 ET调控老年大鼠淋巴细胞基因表达谱中凋亡相关信号分子表达的研究；0502029 与肝癌细胞系HepG2特异性结合单链抗体的筛选与序列分析；0502030 混合皮肤移植中IL-10在自体角朊细胞诱导局部免疫耐受中的作用。     

Adoptive transfer of paternal antigen-hyporesponsive T cells facilitates a Th2 bias in peripheral lymphocytes and at materno-fetal interface in murine abortion-prone matings

PROBLEM: To investigate the Th1/Th2 cytokine changes in abortion-prone recipient mice adoptively transferred by the paternal antigen-hyporesponsive T cells. METHOD OF STUDY: The paternal antigen-hyporesponsive T cells were generated by the anti-B7 monoclonal antibody (mAb) treatment and adoptively transferred into pregnant CBA/J mice of abortion-prone matings on day 4 of gestation. The intracellular expressions of Th1 cell-derived cytokine, tumor necrosis factor-alpha, gamma-interferon and interleukin-2 (IL-2) and Th2 cell-derived cytokine, IL-4 and IL-10 in the maternal spleen were analyzed by flow cytometry, and secretions of the Th1 and Th2 cytokines in supernatant of the feto-placental unit culture were analyzed by an enzyme-linked immunosorbent assay. RESULTS: Our findings showed the increased secretion of Th1 cytokines and the decreased secretion of Th2 cytokines in abortion-prone matings. Treatment with anti-B7 mAbs on day 4 of gestation enhanced Th2 and reduced Th1 cytokine production in abortion-prone matings. Similarly, adoptive transfer of paternal antigen-hyporesponsive T cells induced maternal tolerance to the fetus and displayed a Th2 bias both in the peripheral lymphocytes and at the materno-fetal interface of the abortion-prone matings. CONCLUSIONS: These findings indicate that the Th2 cytokine bias and an increase in fetal viability induced by the anti-B7 mAb treatment can be transferred to other pregnant mice of the abortion-prone matings.     

IL-23/IL-17炎症轴在咪喹莫特诱导的小鼠银屑病样皮肤损害中的作用

 目的：观察IL-23/IL-17炎症轴在咪喹莫特诱导的小鼠银屑病样皮损形成过程中的作用及变化规律。方法：雌性BALB/c小鼠随机分为正常对照组和咪喹莫特组,采用PASI评分观察银屑病样小鼠模型皮损动态变化;光镜观察皮损组织形态学变化;细胞因子抗体芯片技术对比检测两组小鼠血清及皮损组织中细胞因子谱的变化;采用流式细胞小球微阵列术、实时荧光定量PCR和蛋白免疫印迹分析技术对小鼠血清及皮肤组织中细胞因子含量、mRNA和蛋白表达水平进行检测;流式细胞术分析外周血及脾细胞成分。结果：咪喹莫特诱导小鼠产生红斑、鳞屑、增厚等典型的银屑病样皮损,并随着给药时间的延长呈现一个抛物线型的动态变化;经咪喹莫特外用刺激后,小鼠皮肤及血清中IL-23/IL-17轴相关细胞因子、Th1、Th2和Treg类细胞因子含量及表达水平均显著升高。IL-23/IL-17轴细胞因子表达也呈现一个先升高后降低的动态变化过程。咪喹莫特组小鼠外周血及脾细胞中树突状细胞比例显著升高,脾细胞中Th17细胞比例升高,约为正常对照组的3～4倍,Treg细胞比例约为正常对照组的2倍。结论：咪喹莫特诱导小鼠产生的皮损症状、病理学特征及细胞因子改变都与银屑病相似,是进行银屑病研究可行的动物模型,该模型制备后第1～8天可模拟疾病的发展阶段。Th17细胞活化及IL-23/IL-17轴参与了该模型皮损的形成,并呈现一个先升高后降低的动态变化过程。Th1细胞介导的炎症反应也参与了该模型皮损的形成,并且伴随Treg 和Th2类细胞因子的反馈性升高。     

TSH receptor-adenovirus-induced Graves' hyperthyroidism is attenuated in both interferon-gamma and interleukin-4 knockout mice; implications for the Th1/Th2 paradigm

The role of the Th1/Th2 balance in the pathogenesis of murine Graves' hyperthyroidism is controversial. In BALB/c mice injected with adenovirus expressing TSH receptor (TSHR-adeno model), we found that suppression of TSHR-specific Th1 immune responses by exogenous interleukin-4 (IL-4), alpha-galactosylceramide or helminth (Schistosoma mansoni) infection was associated with inhibition of hyperthyroidism, indicating the critical role for Th1 cytokines. In contrast, BALB/c IL-4 knockout (KO), but not interferon-gamma (IFN-gamma) KO mice failed to develop Graves' hyperthyroidism when injected with TSHR-expressing M12 B lymphoma cells (TSHR-M12 model), suggesting the importance of Th2 cytokine IL-4. To reconcile differences in these two models, we used IL-4 KO and IFN-gamma KO BALB/c mice in the TSHR-adeno model. Unlike wild-type (wt) BALB/c mice in which 60% developed hyperthyroidism, only 13 and 7% of IL-4 KO and IFN-gamma KO mice, respectively, became hyperthyroid. Thyroid stimulating antibodies were positive in most hyperthyroid mice. TSHR antibody titres determined by TSH binding inhibition and ELISA were comparable in all three groups. IgG1 and IgG2a TSHR antibody titres were similar in IFN-gamma KO and wt mice, whereas IgG1 TSHR antibody titres and TSHR-specific splenocyte IFN-gamma secretion were lower in IL-4 KO than in IFN-gamma KO and wt mice, respectively. Our results clearly implicate both IFN-gamma and IL-4 in development of hyperthyroidism in the TSHR-adeno model. These data, together with the previous report, also indicate different cytokine requirements in these two Graves' models, with IFN-gamma being more important in the TSHR-adeno than the TSHR-M12 model. Moreover, our previous and present observations indicate a difference in the role of exogenous versus endogenous IL-4 in TSHR-adenovirus induced Graves' hyperthyroidism.     

病毒性心肌炎(病)患者中IFNγ和IL10的表达及药物干预的研究

本研究采用ELISA法检测心肌炎 (病 )患者外周血Th1/Th2相关细胞因子IFN γ及IL 10浓度 ,以RT PCR检测柯萨奇B病毒 (CVB )表达情况 ,并观察“抗柯”注射液给药后的效果。结果表明 ,(1)急性期者 ,CVB RNA阳性者居多 ,Th1均增高 ,Th2类细胞因子IL 10正常或偏低 ;(2 )恢复期者 ,CVB RNA阴性者居多 ,IL 10均增高 ,IFN γ正常或偏低 ;(3)慢性期者 (包括扩张型心肌病 )Th1/Th2均降低 ,内含CVB RNA持续阳性者。表明心肌炎的炎症主要是Th1细胞所介导 ,而Th2类细胞因子对其有抑制作用 ,抗柯注射液提高Th2活性 ,抑制Th1活性。     

Increased T helper 1 cytokine responses by circulating T cells are present in women with recurrent pregnancy losses and in infertile women with multiple implantation failures after IVF

BACKGROUND: We aimed to study T-helper 1 (Th1) and Th2 intracellular cytokine expression in peripheral blood lymphocytes of women with recurrent spontaneous abortions (RSA) or infertility with multiple implantation failures after IVF cycles. METHODS: Twenty-six women with three or more RSA and 23 with two or more IVF failures (14 with no history of spontaneous abortion (SAB) and nine with more than one SAB) comprised the two study groups. Twenty-one non-pregnant healthy multiparous women served as controls. Proportions (%) of lymphocytes containing IFN-gamma, TNF-alpha, IL-4 and IL-10 and the Th1/Th2 ratios of IFN-gamma/IL-4, IFN-gamma/IL-10, TNF-alpha/IL-4 and TNF-alpha/IL-10 in CD3+, CD3+/CD8- (T helper) and CD3+/CD8+ (T suppressor) cells were measured by 4-colour flow cytometry. RESULTS: RSA women demonstrated significantly higher Th1/Th2 ratios of IFN-gamma/IL-4 (P < 0.01), TNF-alpha/IL-4 and TNF-alpha/IL-10 (P < 0.05 each) in CD3+/CD8- T helper cells than those of controls. The proportion of TNF-alpha producing CD3+/CD8- cells (P < 0.05), and the Th1/Th2 ratios of TNF-alpha/IL-4 (P < 0.05) and TNF-alpha/IL-10 (P < 0.005) in CD3+/CD8- cells were significantly higher in women with multiple IVF failures without SAB as compared with those of controls. CONCLUSIONS: The prevalence of dominant Th1 immune responses in peripheral blood lymphocytes may reflect the systemic contribution of Th1 cytokines to RSA or multiple implantation failures in IVF cycles.     

Activation of Peripheral Th17 Lymphocytes in Patients with Asthma

A recently identified interleukin (IL)-17-producing T-helper (Th) lymphocyte subset, which comprises Th17 cells producing hallmark cytokines IL-17A, IL-17F and IL-22, is involved in chronic inflammatory diseases. Elevated gene and protein expressions of IL-17 are manifested in allergic asthma. We further characterized the activation of Th17 cells in asthmatic patients. Peripheral blood mononuclear cells (PBMC) were purified from 31 asthmatic patients and 20 sex- and age-matched control subjects. The number of IL-17A secreting cells in peripheral blood was enumerated by enzyme-linked immunosorbent spot assay. Cell surface expression of Th17-related chemokine receptor CCR6, and plasma level of IL-17A, IL-17F and IL-22, and ex vivo production of IL-17A and IL-22 were measured by flow cytometry and enzyme-linked immunosorbent assay, respectively. The number of peripheral Th17 lymphocytes, expression of CCR6 on Th cells, and ex vivo IL-23, anti-CD3 and anti-CD28 induced production of IL-22 by PBMC were significantly elevated in asthmatic patients compared with control subjects (all p < 0.01). This clinical study further confirmed increased number of peripheral Th17 lymphocytes and cell surface expression of CCR6 receptors on Th cells in asthmatic patients. Pro-inflammatory cytokine IL-23 can exacerbate disease severity by activating pathogenic Th17 lymphocytes to release downstream inflammatory cytokine IL-22 in asthma.     

Changes in the cytokine profile of lupus-prone mice (NZB/NZW)F1 induced by Plasmodium chabaudi and their implications in the reversal of clinical symptoms

We have previously observed that aged lupus-prone (NZB/NZW)Fl (BWF1) mice when infected with Plasmodium chabaudi show an improvement in their clinical lupus-like symptoms. In order to study the mechanisms involved in the long-lasting protective effect of the P. chabaudi infection in lupus-prone mice we analysed specific aspects of the cellular response, namely the profiles of cytokine mRNA expression and cytokine secretion levels in old BWF1 mice, in comparison with uninfected age-matched BWF1 mice and infected or uninfected BALB/c mice. Two months after infection, cells from BWF1 mice were stimulated with concanavalin A (Con A) and demonstrated a recovery of T cell responsiveness that reached the levels obtained with BALB/c cells. Old BWF1 mice showed high levels of interferon-gamma (IFN-gamma) and IL-5 production and correspondingly low levels of IL-2 and IL-4 secretion before infection with P. chabaudi. Infection did not modify the IFN-gamma levels of BWF1 T cells, whereas it considerably increased the secretion of the Th2-related cytokines IL-4, IL-5 and IL-10. In addition, only BWF1 T cells showed increased mRNA expression of tumour necrosis factor-alpha (TNF-alpha) and transforming growth factor-beta (TGF-beta). This counter-regulatory cytokine network of infected BWF1 mice may be involved in the improvement of their lupus symptoms. The results of our investigations using the complex model of P. chabaudi infection can be extended and, by using more restricted approaches, it may be possible to explain the multiple regulatory defects of lupus-prone mice.     

Recombinant ST2 boosts hepatic Th2 response in vivo

Excessive scarring or fibrosis is a common feature of a wide spectrum of diseases characterized by an exaggerated Th2 response. The TLR/IL-1 receptor (IL-1R)-related protein ST2 is expressed in a membrane-bound form selectively by Th2 cells and was shown to be indispensable for some in vivo Th2 responses. ST2 was also found to block TLR signaling. We addressed the impact of the ST2 pathway on fibrogenesis using a mouse model of hepatic injury and fibrosis induced by carbon tetrachloride (CCl(4)). We showed that cytokine production by intrahepatic lymphocytes from CCl(4)-injured liver is abrogated in the absence of TLR-4. Interfering with the ST2 pathway using an ST2-Fc fusion protein accelerated and enhanced hepatic fibrosis, paralleled by the increasing ex vivo secretion of Th2 cytokines IL-4, -5, -10, and -13 by intrahepatic lymphocytes of ST2-Fc-treated, CCl(4)-gavaged mice. Absence of IL-4/13 signaling in IL-4Ralpha-deficient mice obliterated this ST2-Fc effect on fibrogenesis. Moreover, depletion of CD4(+) T cells abrogated ST2-Fc-enhanced Th2 cytokines and accelerated fibrosis. Thus, ST2-Fc caused overproduction of Th2 cytokines by intrahepatic CD4(+) T cells, possibly by modifying TLR-4 signaling in injured liver. This ST2-Fc-driven Th2 response exacerbated CCl(4)-induced hepatic fibrosis.     

CCK-8对KLH免疫小鼠脾细胞Th1/Th2平衡的影响

目的： 探讨八肽胆囊收缩素（CCK-8）对Th1/Th2平衡的调节作用。方法: 给予BALB/c小鼠钥孔戚血蓝蛋白（KLH）免疫同时体内给予不同剂量的CCK-8,酶联免疫吸附试验(ELISA)检测其脾细胞培养上清中Th1型细胞因子γ-干扰素(IFN-γ)、白细胞介素-2（IL-2）和Th2型细胞因子白细胞介素-4（IL-4）、白细胞介素-5（IL-5）水平,逆转录聚合酶链式反应(RT-PCR)法检测脾细胞中IFN-γ、IL-2、IL-4、IL-5 mRNA表达;ELISA法检测血清中Th1型抗KLH抗体IgG2a和Th2型抗KLH抗体IgG1水平。结果: ①KLH免疫使小鼠脾细胞分泌Th1/Th2型细胞因子水平明显增高,mRNA表达增高,KLH免疫同时给予CCK-8可使脾细胞培养上清中IFN-γ、IL-2含量进一步增加和IFN-γ、IL-2mRNA表达增高,而使IL-4、IL-5含量降低,IL-4、IL-5 mRNA表达减低和降低IL-4/IFN-γ比值。②KLH免疫小鼠血清中IgG2a、IgG1发生不同程度增高,CCK-8可使其血清中IgG1水平减低而使IgG2a水平增高。结论: CCK-8可促进KLH免疫小鼠体内Th1反应,使Th2优势反应向Th1方向转变。