Regulatory T cells for tolerance

Regulatory T cells (Tregs) are critical mediators of immune homeostasis and hold significant promise in the quest for transplantation tolerance. Progress has now reached a critical threshold as techniques for production of clinical therapies are optimised and Phase I/II clinical trials are in full swing. Initial safety and efficacy data are being reported, with trials assessing a number of different strategies for the introduction of Treg therapy. It is now more crucial than ever to elucidate further the function and behaviour of Tregs in vivo and ensure safe delivery. This review will discuss the current state of the art and future directions in Treg therapy.     

Function of T regulatory type 1 cells is down-regulated and is associated with the clinical presentation of coronary artery disease

T regulatory type 1 (Tr1) cells can promote tolerance and suppress inflammation. Atherosclerosis may be induced by the proinflammatory activation of cells in the vasculature and the immune system. Hence, we wondered whether defects in Tr1 function were a contributing factor to coronary artery disease (CAD). Data showed that the frequency of IL-10⁺ Tr1 cells was significantly lower in CAD patients than in controls. Compared to healthy controls, Tr1 cells from CAD patients presented lower CTLA-4 but higher PD-1 expression, in addition to lower IL-10 secretion. When co-incubated with Tconv cells, the CD4⁺CD49b⁺LAG-3⁺CD45RO⁺ Tr1 cells presented IL-10-dependent inhibitory effects, and those from CAD patients presented significantly lower suppression capacity than those from healthy controls. Interestingly, the characteristics of Tr1 cells were associated with clinical features of CAD patients. The frequency of Tr1 cells and the IL-10 and LAG-3 expression by Tr1 cells were negatively correlated with the BMI of the CAD patients. In addition, the Tr1 frequency and the LAG-3 and CTLA-4 expression on Tr1 cells were lower in CAD patients with higher numbers of narrowed vessels. Together, these results suggest that in CAD, Tr1 cells present multiple defects, which are associated with the clinical presentation of the disease.     

神经酸及其在预防和治疗脑病中的应用研究进展

神经酸是大脑神经细胞和组织中的一种核心天然成分,具有特殊的生物学功能,对人体健康尤其是脑健康起到至关重要的作用。综述神经酸的生物功能和作用机制、神经酸的制备（包括从元宝枫油中提取分离、化学合成及转基因生物合成）以及神经酸在预防和治疗脑病（包括多发性硬化症、肾上腺脑白质营养不良、Zellweger综合征、阿尔茨海默病等）中的应用研究进展。     

宫颈癌患者癌组织中Th17/Tr细胞明显升高与疾病进程相关

目的 了解宫颈癌患者外周血、肿瘤组织中Th17/Tr细胞的比例,分析其与疾病发生、发展的关系,探讨Th17/Tr比值改变在宫颈癌临床检测中的意义.方法 采用流式细胞术检测32例宫颈癌患者外周血、肿瘤组织标本和15例健康者对照标本中的Th17、Tr细胞;采用直线相关检验方法对晚期宫颈癌组的Th17、Tr细胞进行相关性分析.结果 宫颈癌患者外周血、肿瘤组织中Th17、Tr细胞显著高于健康对照组(P<0.05),晚期宫颈癌组Th17/Tr比值低于早期组(P<0.01),晚期宫颈癌组Th17、Tr表达呈负相关.结论 宫颈癌患者Th17、Tr细胞比例明显升高,提示Th17/Tr比值与宫颈癌的发生发展可能存在着一定的关系,为官颈癌的免疫治疗提供新思路.

Abstract：

Objective To detect the levels of Th17 and regulatory T(Tr)cells in Imripheral blood mononuclear and tumor tissue from patients with cervical cancer and analyze the relationship hetween Th17 and Tr cells in cervical cancer progression.In addition.the significance of the Th17/Tr cells ratio in cervical cancer pathogenesis was discussed.Methods The expression levels of Th17 and Tr cells were determined by flow cytometry from 32 patients with cervical cancer and 15 health people.The mechanism of involvement of Th17 and Tr cells proportionality in cervical cancer pathogenesis and the correlation between Th17 and Trwas assessed by bivariate correlation analysis.Results The expression levels of both Th17 and Tr in patients were higher than control groups,especially in late stage patients Th17 and Tr proportionality lower than early group,and there was a negative correlation between them.Conclusion Th17 and Tr cells proportionality may be involve in the development of cervical cancer so as to provide novel strategies for tumor immunotherapy.     

支气管哮喘患者外周血CD4~+CD25~+调节性T细胞变化及其尘螨过敏状态的测定

目的通过对支气管哮喘患者外周血CD4+CD25+调节性T细胞水平变化和尘螨过敏状态的测定,探讨调节性T细胞在过敏性支气管哮喘发病中的作用。方法用流式细胞仪测定CD4+CD25+Tr占CD4+T细胞的比例,采用过敏原皮试点刺方法测定支气管哮喘患者的尘螨过敏状态。结果 25例正常对照组和支气管哮喘发作组患者外周血CD4+CD25+Tr水平分别为8.66%±1.61%和4.81%±2.76%,两组有显著差异(P<0.01)。14例粉尘螨或屋尘螨(+～++)阳性组和11例粉尘螨或屋尘螨(+++)及以上阳性组的CD4+CD25+Tr水平分别为6.45%±2.08%,和2.73%±2.03%,两组有显著差异。结论哮喘患者体内存在Tr细胞免疫功能平衡失调,CD4+CD25+Tr细胞处于低水平,CD4+CD25+Tr数量和抑制功能减弱或呈低反应性可能是导致支气管哮喘发病的原因之一。粉尘螨或屋尘螨重度过敏患者的外周血CD4+CD25+Tr水平明显低于轻度过敏者,提示CD4+CD25+Tr可能与支气管哮喘的过敏状态有关。     

可用于地方性氟骨症治疗的非处方药品及其作用

自从发现地方性氟骨症后，人们便致力于治疗药品的研究，但由于诸多因素的约束使这项工作进展缓慢。基于对地方性氟骨症机体损害的认识和目前已十分繁荣的药品市场，我们可以从诸多的药品中筛选出能用于地方性氟骨症治疗的药品。作列举了6－7类20余种药品，并对这些药品的药理作用、治疗氟骨症的可能性和治疗机理进行了论述。作提出，应该使用非处方药对氟骨症进行治疗，在氟骨症患中实施“自我药疗”，从而使患得到更多的治疗机会，使地方性氟骨症的治疗工作更深入一步。     

乙肝病毒感染者外周血CD4^＋CD25^＋调节性T细胞的表达及临床意义

目的 探讨乙肝病毒感染者外周血CD4 CD25 调节性T细胞(CD4 CD25 Tr)表达水平及其临床意义.方法 选择乙肝病毒携带者25例、急性乙肝患者26例、慢性乙肝患者38例,26例正常对照,用流式细胞仪检测外周血中CD4 CD25 Tr表达水平;用PCR法检测患者HBV DNA载量.结果 乙肝病毒携带者组与慢性乙肝患者组CD4 CD25 Tr水平(9.93±3.51,11.21±3.29)明显高于对照组(8.12±2.80)(P＜0.01或0.05),急性肝炎组与对照组相比,差异没有显著性.结论 持续性HBV感染者CD4 CD25 Tr表达增加,提示CD4 CD25 Tr在慢性乙型肝炎中担负着重要的免疫调节作用,可能抑制HBV感染者特异性细胞免疫反应,与乙肝病毒感染的慢性化及肝病的临床发生、发展有关.     

Type 1 regulatory T cells are associated with persistent split erythroid/lymphoid chimerism after allogeneic hematopoietic stem cell transplantation for thalassemia

Background

Thalassemia major can be cured with allogeneic hematopoietic stem cell transplantation. Persistent mixed chimerism develops in around 10% of transplanted thalassemic patients, but the biological mechanisms underlying this phenomenon are poorly understood.

Design and Methods

The presence of interleukin-10-producing T cells in the peripheral blood of eight patients with persistent mixed chimerism and five with full donor chimerism was investigated. A detailed characterization was then performed, by T-cell cloning, of the effector and regulatory T-cell repertoire of one patient with persistent mixed chimerism, who developed stable split erythroid/lymphoid chimerism after a hematopoietic stem cell transplant from an HLA-matched unrelated donor.

Results

Higher levels of interleukin-10 were produced by peripheral blood mononuclear cells from patients with persistent mixed chimerism than by the same cells from patients with complete donor chimerism or normal donors. T-cell clones of both host and donor origin could be isolated from the peripheral blood of one, selected patient with persistent mixed chimerism. Together with effector T-cell clones reactive against host or donor alloantigens, regulatory T-cell clones with a cytokine secretion profile typical of type 1 regulatory cells were identified at high frequencies. Type 1 regulatory cell clones, of both donor and host origin, were able to inhibit the function of effector T cells of either donor or host origin in vitro.

Conclusions

Overall these results suggest that interleukin-10 and type 1 regulatory cells are associated with persistent mixed chimerism and may play an important role in sustaining long-term tolerance in vivo. These data provide new insights into the mechanisms of peripheral tolerance in chimeric patients and support the use of cellular therapy with regulatory T cells following hematopoietic stem cell transplantation.