T淋巴细胞中核转录因子κB在膀胱肿瘤细胞抑制T淋巴细胞功能中的作用

目的 :了解T淋巴细胞中核转录因子κB在膀胱肿瘤细胞抑制T淋巴细胞功能中的作用。方法 :1 采用免疫组化法检测与膀胱肿瘤细胞EJ、T2 4、正常移行上皮细胞共培养时T淋巴细胞NF κB。 2 用NF κB激动剂、抑制剂调节T淋巴细胞NF κB活性 ,应用免疫组化法、MTT法 ,了解膀胱肿瘤细胞EJ、T2 4作用下NF κB活性与T淋巴细胞功能的相关性。结果 :1 EJ T淋巴细胞组、T2 4 T淋巴细胞组 ,T淋巴细胞胞核染色阳性细胞的百分比与人正常膀胱移行上皮细胞组、空白对照组相比显著降低 (P <0 0 1) ;2 膀胱肿瘤细胞EJ、T2 4作用下T淋巴细胞NF κB胞核染色阳性细胞的百分比与增殖反应 (A值 )呈显著正相关 (Pearson相关系数 =0 74 4 ,P <0 0 0 1,n =6 0 )。结论 :膀胱肿瘤细胞EJ、T2 4可能通过下调NF κB活性抑制T淋巴细胞增殖功能     

PKCθ激活γδT细胞转录因子NF-κB的作用

目的:探讨经T细胞受体(TCR)途径激活人γδT细胞时,新型蛋白激酶PKCθ在促进转录因子NF-κB活化中的作用.方法:常规分离健康人外周血单个核细胞(PBMC),用结核杆菌耐热性多肽抗原(MtbAg)诱导扩增,获得Vγ9Vδ2 T细胞富集的细胞群(MtbAT).PKCθ抑制剂(Rottlerin)预处理MtbAT,抗CD3单克隆抗体(mAb)刺激后收集细胞,通过电泳迁移率变动分析(EMSA)检测转录因子NF-κB活性变化;经流式细胞术(FCM)检测T细胞活化分子CD69的表达情况.结果:γδT细胞经抗CD3 mAb刺激,NF-κB活性增强;Rottlerin预处理使抗CD3 mAb诱导的NF-κB活化程度显著减弱,并抑制T细胞活化分子CD69的表达.结论:PKC0在人γδT细胞经TCR途径激活NF-κB过程中具有重要作用.     

核因子-κB在蛋白激酶C对支气管哮喘T淋巴细胞增殖和凋亡调控信号转导中的作用

目的　探讨核因子 κB(NF κB)在蛋白激酶C(PKC)对支气管哮喘T淋巴细胞增殖和凋亡调控的信号转导中的作用。方法　哮喘组和正常对照组的豚鼠以及急性发作期哮喘患者和正常对照者的外周血中分离出T淋巴细胞并分别加入PKC激动剂 12 肉豆蔻酰 13 乙酸佛波酯 (PMA)和NF κB抑制剂二硫代氨基甲酸吡咯烷 (PDTC)培养。用免疫组化法检测NF κB的表达 ,用四甲基偶氮唑盐微量比色法测定增殖反应 ,用原位末端终止法观测凋亡。结果　加入PMA培养的哮喘T淋巴细胞NF κB活化细胞百分比和增殖率与空白对照及加入PMA培养的正常T淋巴细胞相比均显著升高 (P <0 .0 1) ,而加入PDTC后以上指标均显著降低 (P <0 .0 1)。加入PMA培养的哮喘T淋巴细胞的凋亡指数与空白对照及加入PMA培养的正常T淋巴细胞相比均显著降低 (P <0 .0 1) ,加入PDTC后以上指标均显著升高 (P <0 .0 1)。T淋巴细胞NF κB活化细胞的百分比与增殖率均呈显著正相关 (r =0 .5 1～ 0 .72 ,P <0 .0 0 1) ,与凋亡指数均呈显著负相关 (r= 0 .5 5～ 0 .71,P <0 .0 0 1)。结论　T淋巴细胞PKC活化后导致增殖增加及凋亡减少的生物信号可能是通过激活NF κB来转导的。T淋巴细胞PKC NF κB信号转导途径的激活可能是哮喘的发病机制之一     

核因子-κB对哮喘患者T淋巴细胞血红素氧合酶-1表达的调控

探讨核因子κB（NF－κB）对哮喘患者T淋巴细胞HO－1表达的转录调节机制。分离18例急性发作期哮喘患者外周血T淋巴细胞，并分成3组培养：对照组、加入NF－κB激动剂肿瘤坏死因子－α（TNF－α）组、同时加入TNF－α和NF－κB抑制剂二硫代氨基甲醇吡咯烷（PDTC）组。培养6h后留取细胞，用逆转录聚合酶链反应（RT－PCR）检测血红素氧合酶－1（HO－1）的mRNA。培养24h后留取细胞用Western印迹法检测HO－1的表达。发现TNF－α组T淋巴细胞HO－1蛋白和mRNA表达水平显著高于对照组（q=44.48、29.94,P均＜0.01)，而同时加入TNF－α和PDTC培养组T淋巴细胞HO－1蛋白和mRNA表达水平显著低于TNF－α组（q=43.23、27.99,P均＜0.01)。可见哮喘患者T淋巴细胞HO－1基因转录可能是通过激活NF－κB进行调控。T淋巴细胞NF－κB－HO氧化激活途径可能是哮喘的发病机制之一。     

双歧杆菌DNA对小鼠巨噬细胞中PKC和NF-κB的影响

目的：探讨青春型双歧杆菌的DNA对巨噬细胞中6种PKC和NF-κB的影响。方法：通过激光共聚焦显微镜观察小鼠腹腔巨噬细胞中PKCα、PKCβI、PKCβII、PKCγ、PKCε和PKCζ的荧光强度,以免疫细胞化学染色法检测巨噬细胞中NF-κB^＋细胞的密度。结果：双歧杆菌DNA注射组小鼠腹腔巨噬细胞中,PKCα和PKCβII的平均荧光强度明显高于对照组（P〈0.01）;而PKCβI、PKCγ、PKCε和PKCζ的平均荧光强度在两组间则无统计学意义（P〉0.05）。双歧杆菌DNA注射组巨噬细胞中,NF-κB^＋细胞的密度显著高于对照组（P〈0.01）。结论：青春型双歧杆菌的DNA可通过活化PKCα、PKCβII和NF-κB来激活巨噬细胞。     

BTLA对调节性T细胞发育及功能的影响

目的 研究B和T淋巴细胞弱化因子(B and T lymphocyte attenuator,BTLA)对调节性T细胞(regulatory T cell,Treg)发育和功能的影响.方法 构建在Treg中特异性敲除BTLA基因的小鼠模型,使用流式细胞术检测该模型小鼠中枢及外周各淋巴器官中T细胞外周环境稳态、T细胞的活...     

模拟微重力条件对神经细胞分泌功能的影响

目的分析微重力条件下和正常重力条件下神经细胞培养的上清液中蛋白质表达的差异。方法用旋转细胞培养系统提供的微重力环境进行神经细胞微重力培养。应用表面增强激光解吸离子化（SELDI）蛋白质芯片技术检测微重力和正常重力条件下神经细胞培养上清液的蛋白质谱。用PBSII—C型蛋白质芯片阅读机读取数据,采用Ciphergen Protein Chip3．2．1软件分析数据。结果WCX2两种蛋白芯片共捕获246个蛋白峰,发现14个差异蛋白。与正常重力培养组蛋白谱相比,11个蛋白在微重力培养后高表达,3个蛋白在微重力培养后低表达。结论微重力条件下和正常重力条件下神经细胞培养的上清液中存在差异蛋白表达,这些差异蛋白为进一步了解失重对神经细胞的影响提供了重要线索。     

模拟微重力培养对实验性自身免疫性脑脊髓炎大鼠淋巴细胞功能的影响

目的观察模拟微重力条件下实验性自身免疫性脑脊髓炎（EAE）大鼠淋巴细胞细胞功能的变化。方法尾根免疫MBP668-86建立EAE模型;12d时处死大鼠,分离培养淋巴结细胞;利用旋转式细胞培养系统进行模拟微重力培养;不同时间点,增殖实验检测细胞增殖、流式检测细胞凋亡、T细胞亚型、Th细胞亚群变化;酶联免疫吸附试验（ELISA）检测上清中细胞因子的变化。结果EAE淋巴细胞针对MBP68-86抗原特异性增殖,在培养20h,60h,80h时,增殖受到抑制（t=3．859,P〈0．01;t=5．933,P〈0．001;t=7．613,P〈0．001）;40h时,增殖受到促进（t=4．015,P〈0．01）。培养24h时,微重力组坏死及凋亡细胞增高（t=3．998,P〈0．01;t=3．705,P〈0．01）,Th细胞降低（t=4．111,P〈0．01）,Th1、Th17和调节性T细胞（Treg）亚群比例升高（t=2．743,P〈0．05;t=4．362,P〈0．01;t=2．945,P〈0．05）。微重力培养40h时,IFN-γ,TNF-α浓度明显升高（t=4．056,P〈0．01;t=4．666,P〈0．01）,TGF-β、IL-6、IL4、IL-17浓度明显降低（t=2．855,P〈0．05;t=2．644,P〈0．05;t=3．154,P〈0．05;t=2．732,P〈0．05）。结论除40h外,MBP668-86。特异性淋巴细胞增殖在模拟微重力环境中被抑制;细胞死亡增多、Th细胞减少,对EAE起重要作用的细胞因子的浓度改变。     

姜黄素下调胸腺基质淋巴细胞生成素表达及功能的研究

目的:为了观察姜黄素对人肥大细胞系HMC-1细胞胸腺基质淋巴细胞生成素(TSLP)表达水平的抑制作用。方法:采用ELISA、定量RT-PCR、免疫印迹及caspase-1活性检测等实验来反映姜黄素的作用。结果:姜黄素能抑制HMC-1细胞TSLP的产生及mRNA的表达,50μmol/L姜黄素的最大抑制率能达到29.5%±5.3%。姜黄素对PMA与A23187诱导的核内NF-κB p65表达也有抑制。此外,降低在激活HMC-1细胞中显著增加的caspase-1活性。结论:本研究揭示了姜黄素可抑制TSLP的表达,对炎症及特应性疾病等有潜在的治疗作用。     

淋巴细胞中NF-κB p65活性水平在Fx1A诱导的口服耐受大鼠中的变化

目的：探讨核因子-κB(NF-κB)p65在口服耐受发生中的活性改变及其意义。方法：雌性Wistar大鼠30只随机分成两组：①口服耐受组，用小剂量(每次8mg／2mL PBS)的Fx1A抗原灌胃。②对照组，用PBS2mL／次灌胃。观察大鼠迟发型超敏反应(DTH)，进行脾淋巴细胞增殖试验，了解大鼠免疫功能的改变。以免疫组化和ELISA法，检测大鼠淋巴组织中NF-κB p65的活性及TGF-β1的表达。结果：与对照组相比较，口服耐受组大鼠DTH和抗原特异性淋巴细胞增殖反应明显受抑制；肠黏膜Peyer’s淋巴结(PP结)中NF-κB p6S的活性及TGF-β1的表达明显增加。脾淋巴组织中NF-κB p65的活性降低，但TGF-B1的表达明显增加。结论：低剂量Fx1A抗原诱导的口服耐受的发生，可能与不同部位免疫细胞内NF-κB p65的活性改变有关。     

The influence of leptin on the activity of lung lymphocytes under simulated microgravity

Exposure to microgravity has been implicated in the compromised immune function in space travellers, resulting in opportunistic infections, poor wound healing, and cancer. Since recent studies have suggested that leptin was capable of modulating immune responses, the purpose of this study was to examine effects of microgravity on the activation and proliferation of rat lung lymphocytes and then to examine the effects of leptin-mediated signal transduction mechanisms of lymphocyte activation in these same conditions. In control conditions (T-flasks cultured cells) leptin was not able by itself to increase lymphocytes proliferation, or induce significant increase of either IL-2 production or expression of lymphocytes activation markers, such as CD25 and CD71, while it markedly enhanced the positive effects induced on these parameters by concanavalin A (ConA). Using clinostatic rotating wall vessel (RWV) bioreactors to simulate a microgravity environment, we found that ConA responsiveness was inhibited. Moreover, under these conditions, leptin was not able to reverse these impaired functions. Accordingly with the above cited inhibitory effects exerted by the simulated microgravity environment, evidence was also obtained of defects in lymphocyte intracellular signal transduction induced by the incubation in RWV bioreactors, namely concerning decreased ConA-mediated PKC activity, and reduced expression of NF-κB, c-fos, and ERK1/2. Again, leptin appeared to be unable in restoring a physiologic increase of these parameters, different from what could be observed after complementation of the ConA-mediated signalling with phorbol myristate acetate, which instead demonstrated to overcome the inhibition of lymphocytes activating functions, in the presence of simulated microgravity conditions.     

模拟微重力对人脐静脉内皮细胞血管生成素产生的影响

目的探讨模拟微重力对人脐静脉内皮细胞（HUVEC）生成血管生成素（ANG）的影响。方法培养HUVEC，分为模拟微重力组、地面静止对照组及剪切力对照组，在培养第24h、48h、72h和96h分别收集培养上清液，用ELISA方法检测ANG的浓度变化；固定一部分细胞，应用免疫细胞化学方法检测ANG在HUVEC中的表达情况。结果无论是应用ELISA方法检测上清液中的ANG，还是应用免疫细胞化学的方法检测ANG在细胞内的表达，均发现与地面静止及剪切力对照组相比，模拟微重力组HUVEC的ANG生成增加（P〈0．05）。结论应用回转器模拟微重力能促进体外培养的HUVEC生成ANG。     

模拟微重力对NIH3T3细胞近日节律基因的影响

目的:研究模拟微重力对NIH3T3细胞近日节律基因表达水平的影响。方法:NIH3T3细胞按照模拟微重力的天数分为5组,RT-PCR检测节律基因mRNA的相对表达水平。结果:实验结果显示五组样品Per1、Per2、Cry1、Bmal1、Clock的相对表达水平存在显著性差异。Per1和Per2基因mRNA的相对表达水平在模拟微重力的第2天、第3天较0天显著升高(P0.05),Per2、Cry1和Clock基因mRNA的相对表达水平在模拟微重力的第4天较其他四组显著降低(P0.05)。结论:近日节律基因的相对表达水平在模拟微重力第2、3天升高,第4天后降低。模拟微重力影响近日节律基因的表达且具有时间依赖性。     

Evaluation of the mechanical properties of rat bone under simulated microgravity using nanoindentation

Exposure to microgravity causes a decrease in bone mass and altered bone geometry due to the lack of weight-bearing forces on the skeleton. The mechanical properties of bone are due not only to the structure and geometry, but also to the tissue properties of the bone material itself. To study the effects of microgravity on bone tissue, the mechanical properties of tail suspension rat femurs were investigated. Twelve Sprague–Dawley rats were randomly divided into two groups, tail suspension (TS) and control (CON). On days 0 and 14, the bone mineral density (BMD) of the femurs was determined by Dual Energy X-ray Absorptiometry. After 14 days, three-point bending was used to test the mechanical properties of the whole femur and nanoindentation was used to measure the mechanical properties of the bone materials. The BMD of femurs in TS was significantly lower than that in CON. In the three-point bending testing, the breaking load, stiffness and energy absorption all decreased significantly in the TS group. In the nanoindentation tests, there was no significant difference between TS and CON in elastic modulus (E), while hardness (H) was significantly decreased and E/H significantly increased in TS. Weightlessness affects the intrinsic mechanical properties of bone at the bone material level. It is necessary to investigate further the effect of microgravity on the collagen bone matrix. Nanoindentation is a relatively new technique that is useful for investigating the above changes induced by microgravity and for assessing the efficacy of intervention.     

Mode of action of plasmolysed yeast on lymphocytes under microgravity stress

A newly developed device to simulate microgravity for space biological investigations under laboratory conditions allowed us to apply a reproducible environmental stress on immunologically active cells. Cell proliferation, soluble IL-2 receptor in the culture supernatant, lymphocyte surface activation markers like CD25 (IL-2R), CD69 and HLA-Dr were the endpoints measured. Untreated donor lymphocyte reactions under microgravity were compared to the same cells treated with an immunomodulator from herbal plasmolysed yeast (Bio-Strath Food Supplement). The main finding is the enhancement of the proliferation inhibition under microgravitational stress by the herbal plasmolysed yeast.     

Modeled microgravity suppressed expansion of the MBP-specific T lymphocytes of rats with experimental autoimmune encephalomyelitis

Experimental autoimmune encephalomyelitis (EAE) is characterized by uncontrolled proliferation of autoreactive T lymphocytes, with markedly increased secretion of pro-inflammatory cytokines. To further dissect the pathogenetic pathways of this disease, we exposed T lymphocytes from EAE rats, which were specific for myelin basic protein (MBP) to a modeled microgravity (MMG) environment, using a rotated cell culture system (RCCS) that was known to suppress proliferation of normal T cells. Following exposure to MMG, the proliferation of EAE lymphocytes decreased dramatically compared to those cultured in unit gravity (UG). At the beginning of MMG, a significant increase of apoptosis of MBP-specific T lymphocytes was observed, while at a later stage, the cytokine secretion profile of exposed MBP-specific T lymphocytes was altered, as was the differentiation of Th subsets. We concluded that the function of MBP-specific T lymphocytes was disordered after exposure to MMG.     

The functional network of ion channels in T lymphocytes

Summary:  For more than 25 years, it has been widely appreciated that Ca²⁺ influx is essential to trigger T-lymphocyte activation. Patch clamp analysis, molecular identification, and functional studies using blockers and genetic manipulation have shown that a unique contingent of ion channels orchestrates the initiation, intensity, and duration of the Ca²⁺ signal. Five distinct types of ion channels – Kv1.3, KCa3.1, Orai1+ stromal interacting molecule 1 (STIM1) [Ca²⁺-release activating Ca²⁺ (CRAC) channel], TRPM7, and Cl_swell– comprise a network that performs functions vital for ongoing cellular homeostasis and for T-cell activation, offering potential targets for immunomodulation. Most recently, the roles of STIM1 and Orai1 have been revealed in triggering and forming the CRAC channel following T-cell receptor engagement. Kv1.3, KCa3.1, STIM1, and Orai1 have been found to cluster at the immunological synapse following contact with an antigen-presenting cell; we discuss how channels at the synapse might function to modulate local signaling. Immuno-imaging approaches are beginning to shed light on ion channel function in vivo . Importantly, the expression pattern of Ca²⁺ and K⁺ channels and hence the functional network can adapt depending upon the state of differentiation and activation, and this allows for different stages of an immune response to be targeted specifically.     

Recruitment of functional subpopulations of T lymphocytes. Initiator T lymphocytes recruit helper T cells for cytotoxic response

Initiator T (Ti) lymphocytes are defined by their ability to recruit other T cell populations in vivo. In this study the function of T cells recruited into draining lymph nodes following injection of Ti cells primed to alloantigens in mixed lymphocyte culture was examined. The results demonstrate that alloantigen-specific helper T cells that interact with cytotoxic T (Tc) lymphocyte precursors are recruited, as shown by the significantly higher frequencies of helper cells in draining lymph nodes compared with controls. However, neither Tc cells nor their precursors are recruited. Recruitment by Ti lymphocytes is therefore selective for certain T cell subsets. Proposals to explain the mechanism, specificity, and selectivity of recruitment are discussed. We suggest that Ti cells have a central role in both the initiation of T cell-dependent immune responses and in the maintenance of immunologic memory. Their function is the rapid mobilization of T cell subclasses to a regional lymphoid organ where the immune response subsequently develops.