Use of CD44 by CD4+ Th1 and Th2 lymphocytes to roll and adhere

Localization of circulating lymphocytes to a site of inflammation is paramount for the development and maintenance of an immune response. In vitro studies using cell lines have previously demonstrated that rolling and adhesion of lymphocytes on endothelium requires CD44 interactions with hyaluronan (HA). To date, whether CD44 has a role in mediating CD4(+)-polarized T-helper 1 (Th1) and Th2 lymphocyte interactions with the endothelium in vivo is yet to be determined. In this study we used intravital microscopy to demonstrate that both Th1 and Th2 lymphocytes use CD44 to roll and adhere to tumor necrosis factor-alpha (TNFalpha)-activated microvasculature. Furthermore, chimeric studies imply that CD44 expression by both the endothelium and lymphocytes is essential for these interactions to occur. HA was also necessary for T cell-endothelial cell interactions in vivo and Th1 and Th2 cells rolled on immobilized HA in vitro via CD44. In vitro, both Th1 and Th2 lymphocytes have increased expression of CD44 and greater binding of fluorescent HA than naive cells. The interactions of Th1 and Th2 cells were entirely dependent upon both P-selectin and CD44 in vivo, but did not appear to be counter ligands in vitro. Taken together, these results suggest that CD44 and HA are key to both Th1 and Th2 lymphocyte interactions with the TNFalpha-activated endothelium and raises the possibility of cooperativity between the P-selectin/PSGL-1 and HA/CD44 pathways for Th1 and Th2 rolling in vivo.     

康艾注射液对代偿期肝硬化患者Th1/Th2及相关细胞因子的影响

目的研究康艾注射液对代偿期肝硬化患者Th1/Th2细胞及相关细胞因子的影响。方法采用流式细胞仪检测康艾注射液治疗代偿期肝硬化患者治疗前、后血清Th1、Th2细胞的变化,用ELISA法检测两组患者治疗前、后血清IFN-γ、IL-10的变化。结果两组治疗前后血清Th1、Th2细胞均明显高于健康对照组(P<0.01),Th1/Th2比值均明显低于健康对照组(P<0.01)。治疗后两组Th1、Th2细胞均较治疗前明显下降(P<0.01),Th1/Th2比值均较治疗前明显上升(P<0.01),治疗组Th1/Th2比值明显高于对照组(P<0.01)。两组患者IL-10治疗后明显下降(P<0.01),治疗组低于对照组(P<0.05);两组患者IFN-γ治疗后明显上升(P<0.01),治疗组高于对照组(P<0.01)。结论康艾注射液可以促使代偿期肝硬化患者Th1/Th2平衡向Th1优势漂移,从而促进炎症吸收,促进病情尽早康复。     

系统性红斑狼疮与Th1/Th2

198 6年Ｍｏｓｍａｎｎ等[1] 首次提出鼠的辅助性Ｔ细胞 (Ｔｈ)可分为Ｔｈ1和Ｔｈ2细胞 ,1991年Ｍａｇｇｉｅ等[2 ] 发现人的Ｔｈ细胞与鼠相似 ,也可分为Ｔｈ1和Ｔｈ2两型。Ｔｈ1主要分泌干扰素 γ (ｉｎｔｅｒｆｅｒｏｎ γ ,ＩＦＮ γ)、白细胞介素 2 (ＩＬ 2 )及淋巴毒素 ,介导细胞免疫反应及迟发超敏反应 ;Ｔｈ2主要分泌ＩＬ 4、ＩＬ 5、ＩＬ 6及ＩＬ 10等 ,介导体液免疫 ,辅助抗体生成 ;少数Ｔｈ细胞称为Ｔｈ3细胞 ,它主要分泌ＴＧＦ β ,起免疫抑制作用。它们均由前体细胞 (Ｔｈ0 )分化而来。在生理条件下 ,机体的Ｔｈ1细胞和Ｔｈ2…     

强直性脊柱炎患者外周血Th1/Th2淋巴细胞类型

目的　通过检测强直性脊柱炎患者外周血中CD4+ 和CD8+ T淋巴细胞分泌细胞因子的情况 ,探讨T淋巴细胞亚群与强直性脊柱炎发病的关系。方法　建立三色流式细胞分析法对强直性脊柱炎患者和健康志愿者外周血中淋巴细胞的胞内细胞因子 (IFNγ、IL 4)和表面抗原 (CD4、CD8)进行分析。同时采用夹心酶联免疫吸附法测定血清中IFNγ和IL 4的水平。结果　无论是CD4+ 还是CD8+ T淋巴细胞 ,分泌IFNγ的细胞群要比分泌IL 4的细胞群多 ;IL 4主要由Th2细胞产生 ,而Th1分泌的IFNγ要比Th2多 ;患者的Th1或Th2型细胞数与炎症活动指标呈负相关。与对照组相比 ,强直性脊柱炎患者外周血中Th1和Th2细胞在受刺激后并未增多。患者外周血中IFNγ水平明显升高 ,而IL 4水平无显著变化 ;IFNγ水平与炎症活动指标无明显相关性。结论　在强直性脊柱炎患者的外周血淋巴细胞中 ,以Th1型细胞为主。但Th1细胞在受刺激后分泌细胞因子的能力比Th2细胞低。     

Th1/Th2细胞因子与蠕虫感染

蠕虫感染后引起复杂的免疫应答中辅助性T细胞处于核心位置,Th1/Th2细胞分泌的细胞因子在蠕虫感染后表达地位的不同,将决定蠕虫感染的发展与转归。本文对Th1/Th2细胞因子在蠕虫感染中的表达研究进展予以综述。     

Th1/Th2细胞与移植免疫耐受

随着器官移植手术的开展,如何诱导宿主对移植器官的特异性免疫耐受引起人们越来越多的关注.近年来随着研究的深入,特别是对一些"免疫特惠器官”的研究,逐渐提出了如免疫偏离、克隆清除、克隆不应答、免疫抑制等诱导免疫耐受的途径[1,2].但人们发现诸如克隆不应答、克隆清除并不能完全解释自身免疫耐受及移植免疫耐受的机制.然而免疫抑制的理论得到了大多数学者的承认,并进行了广泛、深入的研究[3].现在免疫学的研究进展不仅证实了外周免疫抑制性T淋巴亚群的存在,而且研究的重点集中在CD4+的Th1/Th2亚群的转换与免疫耐受之间的关系.     

Th1/Th2炎症极化与肺气肿和肺纤维化

肺气肿具有Ⅰ型T辅助细胞（Th1）炎症极化的特征，表现为损伤过度和修复不足，肺实质的破坏增加，肺间质变薄。与之相反，肺纤维则具有Ⅱ型T辅助细胞（Th2）炎症极化，表现为损伤后修复过度，肺间质增厚，胶原沉积。通过调控Th1和Th2的炎症趋势来控制肺组织的损伤和修复的结局可能会为肺气肿和肺纤维化的防治提供新思路。     

Th1 and Th2 cytokine profiles in sickle cell disease

We have investigated the levels of Th1 (IL-2 and IFN-gamma) and Th2 (IL-4) cytokines in the plasma and supernatants following peripheral blood mononuclear cell culture and mitogen stimulation in a group of 39 patients with sickle cell disease (SCD) made up of 29 SS, 8 Sbeta-thal and 2 Hb SD in steady state. Five SS patients were studied during 7 episodes of vaso-occlusive crisis. Twenty-four control (3 Hb AS and 21 Hb AA) were also studied; 10 were acutely ill while 14 were healthy at the time of the study. The plasma levels of IL-2 and IFN-gamma were similar in the patients and the controls. However, plasma IL-4 was significantly higher among the steady-state SS patients than in the controls. While there was no significant difference in cytokine levels following mitogen stimulation in the different groups, plasma IL-2 to IL-4 and IFN-gamma to IL-4 ratios were significantly lower among the steady-state SS patients, indicating a possible Th2 bias in our sickle cell patients and suggesting a possible mechanism to explain the predisposition of SCD patients to bacterial infections. However, SS patients with good splenic function showed a relative Th1 bias, which may be an additional explanation for the protection against bacterial infections in such patients.     

PD-L1 and PD-L2 are differentially regulated by Th1 and Th2 cells

PD-L1 and PD-L2 are ligands for PD-1, a costimulatory molecule that plays an inhibitory role in regulating T cell activation in the periphery. We find that PD-L1 is highly expressed on inflammatory macrophages as compared with resident peritoneal macrophages but can be induced on resident macrophages by classical activation stimuli such as lipopolysaccharide, IFN-gamma, and polyinosinic-polycytidylic acid. Further up-regulation of PD-L1 on inflammatory macrophages can also be induced by subsequent exposure to lipopolysaccharide and IFN-gamma. In contrast, PD-L2 is not expressed on inflammatory macrophages but can be induced by alternative activation via IL-4. Although PD-L1 is highly inducible on a variety of antigen-presenting cell lines as well as resident macrophages, PD-L2 is most significantly inducible only on inflammatory macrophages. PD-L1 up-regulation depends on TLR4 and STAT1, whereas PD-L2 expression depends on IL-4R alpha and STAT6. Consistent with these results, T helper 1T helper 2 (Th1/Th2) cells also differentially up-regulate PD-L1 and PD-L2 expression on inflammatory macrophages. Hence, Th1 cells as well as microbial products can enhance PD-L1 expression on many different macrophage populations, whereas Th2 cells instruct only inflammatory macrophages to up-regulate PD-L2. These results suggest that PD-L1 and PD-L2 might have different functions in regulating type 1 and type 2 responses.     

人工肝支持系统对慢性重型乙型肝炎Th1/Th2、Tc1/Tc2亚群的影响

目的 研究人工肝支持系统治疗慢性重型乙型肝炎对机体Th1/Th2、Tc1/Tc2亚群的影响.方法 采用流式细胞仪检测人工肝支持系统治疗慢性重型乙型肝炎前、后患者Th1/Th2、Tc1/Tc2亚群的变化.结果 患者Th1/Th2、Tc1/Tc2亚群明显高于对照组,经治疗后有所下降,但仍高于对照组.结论 慢性重型乙型肝炎患...     

Clonal Th2 lymphocytes in patients with the idiopathic hypereosinophilic syndrome

Idiopathic hypereosinophilic syndrome (HES) and Gleich's syndrome are related disorders characterized by persistent or recurrent hypereosinophilia of unknown origin. Elevated IgE levels and polyclonal hypergammaglobulinaemia are considered as markers of benign outcome in this setting as they are generally associated with predominant cutaneous manifestations and favourable response to glucocorticoid therapy. In a previous study, we identified a clonal population of CD3-CD4+ Th2-like lymphocytes secreting interleukin (IL)-5 and IL-4 in peripheral blood of a patient fulfilling the diagnostic criteria of HES with associated serum hyper-IgE. We now extend this observation by describing identical findings in three additional patients, and we compare their clinical and biological parameters with five other patients with HES. Chromosomal abnormalities were detected in purified CD3-CD4+ Th2 cells from three patients, among whom one developed anaplastic null cell lymphoma. We therefore suggest that a careful search for T-lymphocyte clonality and cytogenetic changes should be included in the work-up of HES for adequate management.