Aspartate-β-hydroxylase induces epitope-specific T cell responses in hepatocellular carcinoma

Hepatocellular carcinoma (HCC) has a poor prognosis due to high recurrence rate. Aspartate-β-hydroxylase (ASPH) is a highly conserved transmembrane protein, which is over expressed in HCC and promotes a malignant phenotype. The capability of ASPH protein-derived HLA class I and II peptides to generate antigen specific CD4⁺ and CD8⁺ immune responses is unknown. Therefore, these studies aim to define the epitope specific components required for a peptide based candidate vaccine. Monocyte-derived dendritic cells (DCs) generated from the peripheral blood mononuclear cells (PBMCs) of HCC patients were loaded with ASPH protein. Helper CD4⁺ T cells and CD8⁺ cytotoxic T lymphocytes (CTLs) were co-incubated with the DCs; T cell activation was evaluated by flow cytometric analysis. Immunoinformatics tools were used to predict HLA class I- and class II-restricted ASPH sequences, and the corresponding peptides were synthesized. The immunogenicity of each peptide in cultures of human PBMCs was determined by IFN-γ ELISpot assay. ASPH protein-loaded DCs activated both CD4⁺ and CD8⁺ T cells contained within the PBMC population derived from HCC patients. Furthermore, the predicted HLA class I- and class II-restricted ASPH peptides were significantly immunogenic. Both HLA class I- and class II-restricted peptides derived from ASPH induce T cell activation in HCC. We observed that ASPH protein and related peptides were highly immunogenic in patients with HCC and produce the type of cellular immune responses required for generation of anti-tumor activity.     

Vaccination with Flt3L-induced CD8α dendritic cells prevents CD4 T helper cell-mediated experimental autoimmune myocarditis

Experimental autoimmune myocarditis (EAM) represents a CD4⁺ T helper (Th) cell-mediated mouse model of inflammatory heart disease. Interferon (IFN)-γ, typically produced by Th1 cells, reduces EAM severity in myosin heavy-chain-(MyHC)-α peptide/Complete Freund adjuvant-immunized mice. Thus, developing a vaccination strategy that promotes differentiation of Th1 cells may be beneficial in EAM.     

The immune responses of HLA-A*0201 restricted SARS-CoV S peptide-specific CD8⁺ T cells are augmented in varying degrees by CpG ODN, PolyI:C and R848

The induction of antigen specific memory CD8⁺ T cells in vivo is very important to new vaccines against infectious diseases. In the present study, we aimed to evaluate the immune responses of peptide-specific CD8⁺ T cells induced by HLA-A*0201 restricted severe acute respiratory syndrome-associated coronavirus (SARS-CoV) S epitopes plus CpG oligodeoxynucleotide (CpG ODN), PolyI:C and R848 as adjuvants. Furthermore, the generation, distribution and phenotype of long-lasting peptide-specific memory CD8⁺ T cells were assessed by ELISA, ELISPOT and flow cytometry. Our results showed that antigen specific CD8⁺ T cells were elicited by HLA-A*0201 restricted SARS-CoV S epitopes. Furthermore, the frequency of peptide-specific CD8⁺ T cells was dramatically increased after both prime and boost immunization with peptides plus CpG ODN, whereas slight enhancements were induced following boost vaccination with peptides plus PolyI:C or R848. SARS-CoV S peptide-specific IFN-γ⁺CD8⁺ T cells were distributed throughout the lymphoid and non-lymphoid tissues. Results also demonstrated that the HLA-A*0201 restricted peptide-specific CD8⁺ T cells induced by peptides plus CpG ODN carried a memory cell phenotype with CD45RB⁺ and CD62L⁻ and possessed long-term survival ability in vivo. Taken together, our results implied that HLA-A*0201 restricted SARS-CoV S epitopes plus CpG ODN might be the superior candidates for SARS vaccine.     

An alternative signal 3: CD8⁺ T cell memory independent of IL-12 and type I IFN is dependent on CD27/OX40 signaling

Type I IFN and IL-12 are well documented to serve as so called “signal 3” cytokines, capable of facilitating CD8⁺ T cell proliferation, effector function and memory formation. While their ability to serve in this capacity is well established, to date, no non-cytokine signal 3 mediators have been clearly identified. We have established a vaccine model system in which the primary CD8⁺ T cell response is independent of either IL-12 or type I IFN receptors, but dependent on CD27/CD70 interactions. We show here that primary and secondary CD8⁺ T cell responses are generated in the combined deficiency of IFN and IL-12 signaling. In contrast, antigen specific CD8⁺ T cell responses are compromised in the absence of the TNF receptors CD27 and OX40. These data indicate that CD27/OX40 can serve the central function as signal 3 mediators, independent of IFN or IL-12, for the generation of CD8⁺ T cell immune memory     

CD4+CD25+T细胞研究新进展

CD4 CD25 T细胞是新近才被认识的一类免疫调节细胞,在胸腺中产生,主要发挥抑制性免疫调节功能,表达IL-10 mRNA,细胞表面表达IL-2受体a链(CD25),在维持机体内环境的稳定、抗感染免疫、抗肿瘤免疫、诱导移植耐受及自身免疫性疾病等方面发挥重要作用。     

CD4 T淋巴细胞相关解析

<正>由于人们缺乏机体免疫系统有关知识,在面对淋巴细胞化验单时往往存在疑惑。CD4T淋巴细胞作为常见免疫系统细胞,可用于诊断HIV感染者或艾滋病者。笔者将结合多年临床经验,对CD4T淋巴细胞进行分析,详细如下。CD4+T淋巴细胞分类类似于鼠细胞,人体CD4细胞     

CD4+CD25+T细胞与复发性流产

CD4+CD25+T细胞是一类具有免疫调节功能的细胞.正常情况下在体内发挥免疫抑制作用.该类细胞分泌白细胞介素10(IL-10)、转化生长因子β(TGF-β),表达CD25(IL-2Rα)、叉头蛋白(FOXP3蛋白)及细胞毒性T淋巴细胞抗原4(CTLA-4)分子等,通过细胞间直接接触或细胞因子间接方式广泛参与自身免疫耐受、肿瘤免疫、移植免疫.妊娠类似同种异体移植,妊娠时脱落人母体循环的胎儿抗原刺激CD4+CD25+T细胞的产生并在母胎界面形成免疫耐受微环境,防止胎儿受到母体排斥.CD4+CD25+T细胞数量或功能失调则会导致各种疾病的发生,如自身免疫病,移植物抗宿主病,流产等.在复发性流产患者体内CD4+CD25+T细胞数目及功能明显下降.实验表明增强CD4+CD25+T细胞数量或功能可以阻止移植物抗宿主病和治疗复发性流产.     

慢性丙型肝炎CD8^＋细胞毒T淋巴细胞与CD4^＋T淋巴细胞…

本文从外周血、脾脏、肝脏内ＣＤ８＾＋细胞毒Ｔ淋巴细胞（ＣＴＬ）对靶细胞的细胞毒活性及ＣＤ４＾＋Ｔ淋巴细胞对ＨＣＶ不同基因重组抗原或人工合成多肽的增殖反应，综合了该类细胞在慢性丙型肝炎患者体内的免疫功能状况和研究意义。     

The recombinant tuberculosis vaccine rBCG ΔureC::hly induces apoptotic vesicles for improved priming of CD4 and CD8 T cells

Background

The recombinant BCG ΔureC::hly⁺ (rBCG) vaccine candidate is more efficient than parental BCG (pBCG) against tuberculosis (TB) in preclinical models. Evidence exists for superior CD4 and CD8 T cell stimulation. Although the responsible immune mechanisms are incompletely understood, crosspriming of CD8 T cells has been proposed as a major mechanism underlying better protection of rBCG over pBCG. The present study investigates the role of apoptotic vesicles from pBCG- and rBCG-infected macrophages in crosspriming.

Methods

Apoptotic vesicles were isolated from pBCG- and rBCG-infected mouse macrophages. The priming potential of the isolated vesicles was evaluated in terms of dendritic cell activation and specific T cell stimulation.

Results

Apoptotic vesicles from both pBCG- and rBCG-infected macrophages activated dendritic cells but to a different degree. Overall, rBCG-infected apoptotic vesicles induced more profound CD4 and CD8 T cell responses as compared to pBCG.

Conclusions

These data support the notion that the improved vaccine efficacy of rBCG rests on enhanced crosspriming as a consequence of stronger apoptosis.     

TLR agonists and/or IL-15 adjuvanted mucosal SIV vaccine reduced gut CD4⁺ memory T cell loss in SIVmac251-challenged rhesus macaques

Adjuvant plays an important role in increasing and directing vaccine-induced immune responses. In a previous study, we found that a mucosal SIV vaccine using a combination of IL-15 and TLR agonists as adjuvant mediated partial protection against SIVmac251 rectal challenge, whereas neither IL-15 nor TLR agonists alone as an adjuvant impacted the plasma viral loads. In this study, dissociation of CD4⁺ T cell preservation with viral loads was observed in the animals vaccinated with adjuvants. Significantly higher levels of memory CD4⁺ T cell numbers were preserved after SIVmac251 infection in the colons of the animals vaccinated with vaccine containing any of these adjuvants compared to no adjuvant. When we measured the viral-specific CD8⁺ tetramer responses in the colon lamina propria, we found significantly higher levels of gag, tat, and pol epitope tetramer⁺ T cell responses in these animals compared to ones without adjuvant, even if some of the animals had similarly high viral loads. Furthermore, this CD4⁺ T preservation was positively correlated with increased levels of gag and Tat, but not pol tetramer⁺ T cell responses, and inversely correlated with beta-chemokine expression. The pre-challenged APOBEC3G expression level, which has previously been shown inversely associated with viral loads, was further found positively correlated with CD4⁺ T cell number preservation. Overall, these data highlight one unrecognized role of adjuvant in HIV vaccine development, and show that vaccines can produce a surprising discordance between CD4⁺ T cell levels and SIV viral load.     

In vitro derivation of interferon-γ producing, IL-4 and IL-7 responsive memory-like CD4(+) T cells

CD4⁺ memory is critical for successful protection against pathogenic challenge. As such, understanding the heterogeneity of cells that arise and survive after initial stimulation of naïve CD4⁺ T cells will aid in the design of more successful vaccines. In previous studies, in vivo experimental systems have been extensively used to generate functional memory responses by lymphocytes. Here, we have attempted to develop an in vitro experimental system to generate memory CD4⁺ T lymphocytes. CD4⁺ T cells stimulated through the antigen receptor complex were examined for their memory-like characteristics after 3 weeks of cell culture. A subset of surviving cells expressed high levels of CD44 and low levels of CD45RB (CD44^hiCD45^lo), a phenotype that is similar to bonafide memory CD4⁺ T cells. In vitro generated memory-like CD4⁺ T cells secreted higher levels of IFN-γ, with rapid kinetics, upon re-stimulation than their naïve counterparts. In addition, these memory-like CD4⁺ T cells did not produce either IL-2 or IL-4 but readily proliferated when cultured in the presence of IL-7 and IL-4. These observations suggest that CD4⁺ cells surviving the expansion phase of immune response produce a Th1-signature cytokine and retain responsiveness to IL-4, a Th-2 cytokine, as well as to a well described survival factor, interleukin-7.     

儿童免疫性血小板减少症IL-27、CD4~+CD45RA~+T及CD4~+CD45RO~+T细胞变化

目的检测免疫性血小板减少症患儿外周血细胞因子IL-27、CD4~+T细胞表面抗原CD45RA和CD45RO表达的变化,探讨其在ITP发病过程中的作用。方法新诊断ITP患儿35例,正常体检儿童35例作为对照,ELISA法检测血清IL-27水平、流式细胞术法检测外周血CD4~+T细胞CD45RA和CD45RO的表达率,采用t检验、直线相关分析进行比较。结果血清IL-27浓度ITP组(195.35±70.30)ng/L,对照组(301.25±125.40)ng/L,差异有统计学意义(P0.01);CD4~+CD45RA+T细胞表达率ITP组(26.34±5.58)%,对照组(30.56±5.35)%;CD4~+CD45RO~+T细胞表达率ITP组(55.12±7.85)%,对照组(48.45±6.74)%,差异均有统计学意义(P0.01);血清IL-27水平与外周血小板计数无相关性(r=0.202,P=0.575)。结论 IL-27、CD4~+CD45RA+T细胞和CD4~+CD45RO~+T细胞介导的细胞免疫异常可能参与了ITP发病。     

CD4^＋CD25^＋T细胞与复发性流产

CD4 CD25 T细胞是一类具有免疫调节功能的细胞。正常情况下在体内发挥免疫抑制作用。该类细胞分泌白细胞介素10(IL-10)、转化生长因子β(TGF-β),表达CD25(IL-2Rα)、叉头蛋白(FOXP3蛋白)及细胞毒性T淋巴细胞抗原4(CTLA-4)分子等,通过细胞间直接接触或细胞因子间接方式广泛参与自身免疫耐受、肿瘤免疫、移植免疫。妊娠类似同种异体移植,妊娠时脱落入母体循环的胎儿抗原刺激CD4 CD25 T细胞的产生并在母胎界面形成免疫耐受微环境,防止胎儿受到母体排斥。CD4 CD25 T细胞数量或功能失调则会导致各种疾病的发生,如自身免疫病,移植物抗宿主病,流产等。在复发性流产患者体内CD4 CD25 T细胞数目及功能明显下降。实验表明增强CD4 CD25 T细胞数量或功能可以阻止移植物抗宿主病和治疗复发性流产。     

In vitro cytotoxicity of Cu²⁺, Zn²⁺, Ag⁺ and their mixtures on primary human endometrial epithelial cells

BackgroundTo avoid the inherent disadvantages of copper-containing intrauterine device (Cu-IUD) induced by free Cu²⁺, two other well-performing metal ions, namely, Ag⁺, with long-effective antimicrobial properties, and Zn²⁺, as an essential trace element, are being considered for use in the future as multifunctional IUDs. The purpose of this study was to assess the cytotoxicity of these metal ions and their mixtures on primary human endometrial epithelial cells (HEECs) cultured in vitro and to provide several choices of alternative potential materials for creating excellent IUDs in the future.Study DesignWith the use of 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide-formazan (MTT-f) production, the cytotoxic effects of single metal ions (Cu²⁺, Zn²⁺, Ag⁺) on HEECs after exposure for 24, 48 or 72 h were investigated, and the synergistic and antagonistic effects of two ions applied simultaneously were also assessed.ResultsThe cytotoxicity of the metal ions on HEECs ranked as follows: Ag⁺>Cu²⁺>Zn²⁺. All combinations of those tested indicated that the Cu²⁺+Zn²⁺ system exhibited an antagonistic effect absolutely, the Zn²⁺+Ag⁺ system showed both antagonism and slight synergism, and asynergistic effect was observed in the Cu²⁺+Ag⁺ system.ConclusionFrom a perspective of favorable biocompatibility, Zn²⁺ and the Cu²⁺+Zn²⁺ mixture showed evidence of potential components for use in future IUDs. Although having strong cytotoxicity, Ag⁺ with its low release rate and broad-spectrum antibiotic activity may also be considered. The study also demonstrated the relative stability of Cu²⁺ as a classic material of IUD.     

煤工尘肺壹期患者周围血CD4+ CD25+调节性T细胞与CD4+ 、CD8+T细胞表达及意义

目的 探讨周围血CD4+ CD25+调节性T细胞(CD4+ CD25+ Treg)与CD4+、CD8+T细胞在煤工尘肺(CWP)壹期中的水平变化及临床意义.方法 采用流式细胞术检测103例CWP壹期患者(CWP组)、45例具有与CWP组相同接尘条件的健康井下接尘矿工(接尘对照组)及48例井上健康检查人员(正常对照组)周围血CD4+ CD25+ Treg及其CD4+、CD8+T细胞水平.结果 与接尘对照组和正常对照组比较,CWP组CD4+ CD25+ Treg、CD4+T细胞水平及CD4+CD25 +/CD4+、CD4+ CD25 +/CD8+比值明显升高,差异具有统计学意义(均P＜0.01),CD8+T细胞则无明显改变(P＞0.05),但接尘对照组CD8+T细胞水平明显低于正常对照组(P＜0.05).CWP组吸烟患者CD4+ CD25+ Treg水平和CD4+ CD25 +/CD4+比值均明显高于非吸烟患者,差异有统计学意义(均P＜0.01).CWP组CD4+ CD25+ Treg与CD4+T细胞呈正相关[相关系数(r) =0.627,P＜0.01],与CD8+T细胞呈负相关(r=-0.362,P＜0.01),CD4+T细胞与CD8+T细胞呈负相关(r=-0.436,P＜0.01).结论 CWP壹期患者周围血CD4+ CD25+ Treg表达增加,可能影响CD4+T细胞和CD8+T细胞的分布平衡,导致细胞免疫功能紊乱;吸烟可加重T细胞亚群分布失衡.     

CD27和CD28在肺结核病人抗原特异性CD4＋T细胞中的表达分析

目的 研究肺结核病人与健康人外周血结核抗原特异性CD4^＋T细胞中CD27和CD28的表达情况,了解不同分化程度T细胞在结核发病中的作用.方法 以荧光标记的抗CD4、CD154、CD27、CD28四种抗体共染色,用流式细胞仪检测肺结核病人和健康人外周血CD4^＋ CD154^＋ T细胞中CD27和CD28的分布比例.通过对比分析,了解不同分化阶段CD4^＋T细胞在病人与健康人之间的分布差异.结果 特异性结核抗原刺激后,肺结核病人外周血CD4^＋ CD154^＋ T细胞中CD27^＋ CD28^＋（早期分化）、CD27^- CD28^＋ 和CD27^＋ CD28^-（中期分化）以及CD27^-CD28^-（晚期分化）T细胞的比例分别为（49.55±6.15）%、（26.85±3.87）%、（7.2±1.37）%和（16.35±3.97）%;而在健康人中这四群细胞的比例分别为（51.81 ±4.94）%、（29.83±5.33）%、（12.65±4.48）%和（5.7±2）%.结核病人与健康人以早期分化CD4^＋T细胞为主,在晚期分化CD4^＋T细胞比例上差异有统计学意义（t=2.26,P〈0.05）.结论 肺结核病人抗原特异性CD4^＋T细胞中晚期分化阶段细胞的比例显著高于健康人,提示抗原特异性CD4^＋T细胞的分化程度与结核病相关.     

小儿类风湿关节炎患者外周血CD4+、CD8+T细胞CD69的表达

目的:探讨小儿类风湿关节炎患者外周血CD4~+、CD8~+T细胞CD69的表达。方法:选取我院2013年6月~2015年6月收治的30例类风湿性关节炎患儿的外周血标本,将其归为观察组,再选取30例健康儿童的外周血标本作为对照组,采用流式细胞仪对两组患儿外周血中的外周血CD4~+、CD8~+T细胞CD69进行分析,对其在疾病中的作用进行分析。结果:类风湿性关节炎患儿外周血中的CD69~+CD4~+、CD69~+CD8~+T细胞含量显著高于对照组儿童,药物治疗后观察组患儿的T细胞含量显著下降,差异存在统计学意义(P0.05)。结论:CD69可以作为类风湿性关节炎诊断、治疗以及转归的生物学标记。     

CD4+CD25+调节性T细胞在艾滋病病毒感染中的作用

CD4+CD25+调节性T细胞(Tregs)是一类具有特殊免疫调节功能的T细胞亚群,是Tregs的重要组成部分,参与多种感染性疾病的免疫应答,在病毒感染的慢性化、免疫病理、阻止自身免疫应答和维持机体免疫平衡等方面发挥重要的作用.此文就CD4+CD25+Tregs在HIV感染进程中的作用作了综述.     

淋巴瘤患者外周血T细胞CD88+CD28-、CD4+CD25+的表达及意义

目的 探讨恶性淋巴瘤患者外周血T细胞CD88+CD28-、CD4+CD25+的表达及意义.方法 采用流式细胞术检测35例恶性淋巴瘤患者外周血T细胞CD88+CD28-、CD88+CD28-、及CD4+CD25+.结果 恶性淋巴瘤患者外周血T细胞CD88+CD28-、CD88+CD28-、CD4+CD25+与正常对照差异有统计学意义(P<0.01);治疗有效后三者趋于正常(P>0.05);而无效组与正常时照组相比差异仍有统计学意义(P<0.01).结论 恶性淋巴瘤患者外周血T细胞CD88+CD28-、CD88+CD28-、及、CD4+CD25+表达异常,不同治疗效果表达不同,恶性淋巴瘤患者有免疫功能异常,治疗有效后免疫功能恢复正常.     

转录因子FOXP3与CD4+CD25+调节性T细胞

Foxp3是近年来发现的一种影响调节性T细胞发育的关键转录因子,是forkhead/winged-helix转录因子家族的新成员,可能是CD4~ CD25~ Treg表面特异性标志。在小鼠中常以foxp3