Precommitment of CD4+CD8+ thymocytes to either CD4 or CD8 lineages.

CD4+ and CD8+ mature T cells arise from CD4+CD8+ precursors in the thymus. During this process, cells expressing T-cell receptors (TCRs) reactive with self major histocompatibility complex (MHC) class I or II molecules are positively selected to the CD8 or CD4 lineage, respectively. It is controversial whether lineage commitment of CD4+CD8+ thymocytes is controlled directly by TCR specificity for MHC (instructional model) or, alternatively, by processes that operate independently of TCR specificity (stochastic model). We show here that CD4+CD8+ thymocytes bearing a MHC class I-restricted transgenic TCR can be subject to two alternative developmental fates. One population of CD4+CD8+ cells is positively selected by MHC class I molecules to the CD8 lineage as expected, whereas the other CD4+CD8+ population rearranges endogenous TCR genes and is positively selected by MHC class II molecules to the CD4 lineage. Blocking TCR-MHC class II interactions in vivo does not interfere with the generation of CD4+CD8+ cells expressing endogenous TCRs but does prevent their subsequent maturation to CD4+ cells. These data support a version of the stochastic model in which CD4+CD8+ thymocytes are precommitted to the CD4 or CD8 lineage independently of TCR specificity for MHC and prior to positive selection.     

Agranular CD4+CD56+ blastic natural killer leukemia/lymphoma

Blastic natural killer cell leukemia/lymphoma (blastic NKL/L) is characterized by blastic morphology and a distinctive immunophenotype combining blastic features and cytologically resembling acute myeloid or lymphoid leukemia. The clinical, pathologic, and cytogenetic features of blastic NKL/L have not yet been systematically identified. We report herein a case of blastic NKL/L with skin lesion, adenopathy, and systemic lymphoadenopathy. The identified tumor cells were positive for CD4 and CD56, and negative for T-cell, B-cell, and myeloid markers. T-cell receptor beta, gamma, delta, and immunoglobulin heavy chain genes in the bone marrow cells showed germ-line configurations. Southern blot analysis with a terminal probe did not reveal any Epstein-Barr virus infection. Although patients diagnosed as blastic NKL/L have generally shown chemotherapy resistance and poor prognosis, our patient was treated with a combined chemotherapy, which is also used for acute lymphoblastic leukemia, and has maintained complete remission (CR) for more than 13 months. In addition to clinical investigations, we thoroughly analyzed his karyotype by using a combination of G-banding and a new technique, spectral karyotyping. The karyotype was described as 45, XY, der(1)t(1;20)(p32;q11.2), der(6) (1pter-->1p32:: 6p21.1-->6q13:: 7q11.2-->7qter), der(7) t(7;20)(q11.2;q11.2), t(13;14)(q14;q32), der(13)t(6;13) (p21.1; q14), -20.     

COPD患者CD4+/CD8+、CD8+CD28+ T淋巴细胞检测意义

目的分析慢性阻塞性肺疾病(COPD)患者CD4⁺/CD8⁺、CD8⁺CD28⁺调节性T淋巴细胞检测意义。 方法收集2018年6月至2019年6月于我院就诊收治的98例COPD患者的临床资料,随访18个月,根据患者生存情况分为存活组85例与死亡组13例,采用流式细胞术检测COPD患者CD4⁺/CD8⁺、CD8⁺CD28⁺调节性T淋巴细胞,应用ROC曲线分析CD4⁺/CD8⁺及CD8⁺CD28⁺调节性T淋巴细胞预测COPD患者死亡的价值。 结果两组患者PaO₂、FEV₁占预测值、有创机械通气例数所占比、CD4⁺/CD8⁺以及CD8⁺CD28⁺ T淋巴细胞占比存在统计学差异(P<0.05);多因素Logistic回归分析,PaO₂、FEV₁占预测值、有创机械通气、CD4⁺/CD8⁺、CD8⁺CD28⁺是COPD预后的独立危险因素(P<0.05);CD4⁺/CD8⁺、CD8⁺CD28⁺ T淋巴细胞水平预测COPD患者死亡的最佳截断值分别为1.76%、7.85%,二者联合预测COPD患者死亡的ROC曲线下面积(AUC)为0.913(95%CI: 0.862~0.947),明显高于单项CD4⁺/CD8⁺的AUC值(0.784, 95%CI: 0.602~0.850)及CD8⁺CD28⁺的AUC值(0.795,95%CI：0.596~0.861)。 结论COPD患者CD4⁺/CD8⁺、CD8⁺CD28⁺ T淋巴细胞与患者预后密切相关,二者联合检测对COPD患者预后有意义。     

Soluble CD163 Levels and CD163+CD14+ Monocyte/Macrophage Counts in Patients with Asthma

Background: CD163-expressing macrophages are involved in the inflammatory response in asthma. Objective: To assess sputum and serum soluble CD163 (sCD163) and cytokine levels in patients with asthma. Further discussed was the difference between sCD163 and other classic inflammatory mediators. Methods: Sputum was successfully induced in asthma patients (n=85) and healthy controls (n=21). Interleukin (IL)-4, IL-5, IL-1β, IL-8, IL-9, IL-6, and sCD163 levels in sputum were measured. CD163+ monocytes in blood were evaluated using flow cytometry. Results: Sputum sCD163 level significantly increased in asthma (median: 22.4 pg/ml; IQR, 11.52-42.91), unlike healthy controls (10.54 pg/ml;9.85-23.5; P<0.001). Sputum sCD163 (P=0.020) and serum sCD163 (P=0.032) levels were significantly higher in patients with severe asthma compared to those with mild/moderate asthma. Percentage of CD163+ monocytes in patients with asthma was significantly lower than the controls (P<0.001). Conclusion: Increased sCD163 levels in sputum are associated with the impairment of lung function.     

Microscopic colitis patients have increased proportions of Ki67+ proliferating and CD45RO+ active/memory CD8+ and CD4+8+ mucosal T cells

BackgroundCollagenous colitis (CC) and lymphocytic colitis (LC) are chronic inflammatory bowel disorders of unknown etiology. This study investigated phenotypic characteristics of the mucosal lymphocytes in CC and LC.MethodsLamina propria and intraepithelial lymphocytes (LPLs, IELs) isolated from mucosal biopsies from CC (n = 7), LC (n = 6), as well as LC or CC patients in histopathological remission, (LC-HR) (n = 6) and CC-HR (n = 4) and non-inflamed controls (n = 10) were phenotypically characterized by four-color flow cytometry.ResultsThe proportions of CD8⁺ IELs were increased in CC and LC (p < 0.01) compared to controls. Increased proportions of CD45RO⁺CD8⁺ IELs and LPLs were observed in LC and even more in CC patients (p < 0.01). Both CC (p < 0.05) and LC patients had elevated proportions of CD4⁺8⁺ IELs and LPLs compared to controls. The proportions of CD45RO⁺ cells were increased in CD4⁺8⁺ IELs and LPLs (p < 0.05) in CC and LC patients compared to controls. Both CC (p < 0.05) and LC patients had higher proportions of Ki67⁺CD8⁺ IELs and LPLs compared to controls.In contrast, decreased proportions of CD4⁺ LPLs were observed in CC and LC as well as CD4⁺ IELs in LC compared to controls. Increased proportions of Ki67⁺CD4⁺ IELs and LPLs (p < 0.05) were observed in CC and LC patients.CC-HR but not LC-HR patients demonstrated normalized proportions of both IELs and LPLs compared to CC and LC patients respectively.ConclusionLC and CC patients have differences in mucosal lymphocyte subsets, with increased proportions of Ki67⁺ and CD45RO⁺ CD8⁺ and CD4⁺8⁺ mucosal T cells.     

CD4CD4+和CD8CD4+ T淋巴细胞与动脉粥样硬化相关性研究进展

在动脉粥样硬化的发生发展过程中CD4+和CD8+T淋巴细胞有着重要的意义,近年来越来越多的研究显示了CD4+和CD8+T淋巴细胞参与了动脉粥样硬化的免疫炎症反应,受到了国内外学者的关注,同时,也成为心血管领域和免疫学界难以攻关的课题。本文对CD4+和CD8+T淋巴细胞与动脉粥样硬化相关性研究进展做一简要综述。     

Identification of biclonal (duplex) leukaemic cells expressing either CD4+/CD8- or CD4-/CD8+ from a patient with adult T-cell leukaemia/lymphoma

A 24-year-old Japanese woman was admitted to our hospital in 1987 with a chief complaint of skin eruptions, and was diagnosed as having chronic ATLL. In 1993 the leucocyte count increased gradually to 126.0x10⁹/l with 91.5% abnormal lymphocytes expressing two different types of antigenicity, either CD4⁺/CD8^- or CD4^-/CD8⁺. Monoclonal integration of human T-cell lymphotropic virus type-I proviral DNA was detected at different sites of the genomic DNA in each cell type. These studies clearly indicate that CD4⁺/CD8^- and CD4^-/CD8^- leukaemic cells originated from two independent clones.     

Ontogeny of CD4+CD25+ regulatory/suppressor T cells in human fetuses

Little is known about the ontogeny of naturally occurring CD4(+)CD25(+) regulatory/suppressor T cells that play a major role in maintaining self-tolerance in mice and humans. In rodents, thymectomy on day 3 of life leads to multiple organ-specific autoimmune diseases that can be prevented by adoptive transfer of regulatory T cells, suggesting their neonatal development. We investigated regulatory T-cell ontogeny in 11 human fetuses. Together with the first mature T cells, thymic CD4(+)CD25(+) cells were detected as early as 13 weeks of gestation. Thymic CD25(+) cells appeared to be positively selected at the CD4(+)CD8(+)CD3(hi) differentiation stage, as assessed by CD1a and CD69 expression. The proportion of thymic CD4(+)CD25(+) cells appeared quite stable with age, around 6% to 7%, similar to the proportion observed in infant thymi. Extrathymic CD4(+)CD25(+) T cells could hardly be detected at 13 weeks of gestation but were present from week 14 onwards. As adult regulatory T cells, purified CD4(+)CD25(+) fetal cells were anergic and suppressed T-cell proliferative responses; they expressed intracellular cytotoxic T-lymphocyte-associated antigen 4 (CTLA-4) and Foxp3 mRNA. Altogether, our results indicate that the generation of regulatory/suppressor T cells is consubstantial to the generation of a functional and self-tolerant immune system.     

Human CD8+CD25+ thymocytes share phenotypic and functional features with CD4+CD25+ regulatory thymocytes

CD8+CD25+ cells, which expressed high levels of Foxp3, glucocorticoid-induced tumor necrosis factor receptor (GITR), CCR8, tumor necrosis factor receptor 2 (TNFR2), and cytotoxic T-lymphocyte-associated antigen 4 (CTLA-4) mRNAs, were identified in the fibrous septa and medullary areas of human thymus. Activated CD8+CD25+ thymocytes did not produce cytokines, but most of them expressed surface CTLA-4 and transforming growth factor beta1 (TGF-beta1). Like CD4+CD25+, CD8+CD25+ thymocytes suppressed the proliferation of autologous CD25-T cells via a contact-dependent mechanism. The suppressive activity of CD8+CD25+ thymocytes was abrogated by a mixture of anti-CTLA-4 and anti-TGF-beta1 antibodies and it was mediated by their ability to inhibit the expression of the interleukin 2 receptor alpha chain on target T cells. These results demonstrate the existence of a subset of human CD8+CD25+ thymocytes sharing phenotype, functional features, and mechanism of action with CD4+CD25+ T regulatory cells.     

非小细胞肺癌患者CD3+、CD4+、CD8+、CD44+表达的临床研究

目的研究非小细胞肺癌患者外周血淋巴细胞中CD3+、CD4+、CD8+、CD4+4的表达水平。方法取65例非小细胞肺癌患者及22例健康正常人外周静脉血,应用流式细胞仪检验非小细胞肺癌患者(实验组)与健康人外周血淋巴细胞中(对照组)CD3+、CD4+、CD8+、CD4+4的表达水平。结果实验组与对照组CD3+、CD3+CD4+、CD3+CD8+、CD4+4在淋巴细胞中的比例存在显著性差异(P<0.05),其中,实验组占总淋巴细胞的比例分别为48.07±10.33%、30.93±6.68%、17.13±3.37%、55.45±4.35%;对照组CD3+、CD3+CD4+、CD3+CD8+、CD4+4占总淋巴细胞的比例分别为58.83±10.88%、34.89±6.45%、23.91±4.42%、62.85±7.56%;但鳞癌与腺癌组CD4+4的表达无显著性差异(P>0.05),其中,鳞癌组CD4+4所占比例为61.32±8.06%,腺癌组为64.43±6.76%。结论非小细胞肺癌患者外周血T细胞亚群及CD4+4的表达水平较正常组均低,其表达水平与组织类型无关。     

CD4+ CD25+ CD127dim/-调节性T淋巴细胞对肝星状细胞增殖及功能的影响

目的 了解CD4+ CD25+ CD127dim/-调节性T淋巴细胞在体外对肝星状细胞(HSC)增殖以及功能的影响,初步探讨调节性T淋巴细胞促肝纤维化的机制。方法传代培养HSC LX-2,将免疫磁珠细胞分选(MASC)法分离所得慢性乙型肝炎患者调节性T淋巴细胞与HSC LX-2按不同方式共培养5d,以单独培养的HSC作为对照,细胞计数试剂盒-8（CCK-8）法检测共培养HSC增殖情况,ELISA法检测上清液中转化生长因子(TGF)β1含量,放射免疫法检测HSC分泌HA、PCⅢ水平。统计学处理采用LSD-t检验。结果 5例调节性T淋巴细胞与HSC比例为1.5∶1时HSC增殖最为明显,10例直接接触共培养与使用Transwell系统共培养调节性T淋巴细胞与HSC吸光度值分别为(0.713±0.032)、(0.735±0.028) cpm,均较对照组的（0.677±0.029）cpm增殖明显(t=5.4003,8.7878;均P＜0.01)。10例直接接触共培养与Transwell组细胞上清液中TGFβ1浓度分别为(781.59±76.45)、（813.53±60.62）pg/mL,显著高于对照组的(722.51±59.66) pg/mL（t=4.0014,6.1653;均P＜0.01）;HA浓度分别为（433.57±27.90）、（445.40±23.73）ng/mL,显著高于对照组的（415.83±19.44）ng/mL（t=3.3124,5.5231;均P＜0.01）;PCⅢ浓度分别为(21.93±1.71)、(23.12±1.87) ng/mL,显著高于对照组的（20.10±1.49）ng/mL(f=4.8082,7.9436;均P＜0.01)。且Transwell组各项结果均显著高于直接接触组(t=3.3875,2.1639,2.2107,3.1354;均P＜0.05)。结论CD4+ CD25+ CD127dim调节性T淋巴细胞可促进共培养的HSC增殖及其HA、PCⅢ的分泌。体外实验证明,CD4+ CD25+ CD127dim/-调节性T淋巴细胞具有促进肝纤维化的重要作用。     

CD4+CD25+Foxp3+ regulatory T cells induce alternative activation of human monocytes/macrophages

CD4(+)CD25(+)Foxp3(+) regulatory T cells (Tregs) are potent suppressors of the adaptive immune system, but their effects on innate immune cells are less well known. Here we demonstrate a previously uncharacterized function of Tregs, namely their ability to steer monocyte differentiation toward alternatively activated macrophages (AAM). AAM are cells with strong antiinflammatory potential involved in immune regulation, tissue remodeling, parasite killing, and tumor promotion. We show that, after coculture with Tregs, monocytes/macrophages display typical features of AAM, including up-regulated expression of CD206 (macrophage mannose receptor) and CD163 (hemoglobin scavenger receptor), an increased production of CCL18, and an enhanced phagocytic capacity. In addition, the monocytes/macrophages have reduced expression of HLA-DR and a strongly reduced capacity to respond to LPS in terms of proinflammatory mediator production (IL-1beta, IL-6, IL-8, MIP-1alpha, TNF-alpha), NFkappaB activation, and tyrosine phosphorylation. Mechanistic studies reveal that CD4(+)CD25(+)CD127(low)Foxp3(+) Tregs produce IL-10, IL-4, and IL-13 and that these cytokines are the critical factors involved in the suppression of the proinflammatory cytokine response. In contrast, the Treg-mediated induction of CD206 is entirely cytokine-independent, whereas the up-regulation of CD163, CCL18, and phagocytosis are (partly) dependent on IL-10 but not on IL-4/IL-13. Together these data demonstrate a previously unrecognized function of CD4(+)CD25(+)Foxp3(+) Tregs, namely their ability to induce alternative activation of monocytes/macrophages. Moreover, the data suggest that the Treg-mediated induction of AAM partly involves a novel, cytokine-independent pathway.     

Action of human interleukin-4 and stem cell factor on erythroid and mixed colony formation by peripheral blood-derived CD34+c-kithigh or CD34+c-kitlow cells

We studied the interaction of interleukin (IL)-4 and other burst-promoting activity (BPA) factors, such as IL-3, granulocyte/macrophage colony-stimulating factor (GM-CSF), IL-9 and stem cell factor (SCF), on erythroid burst-forming unit (BFU-E) and erythrocyte-containing mixed (CFU-Mix) colony formation in serum-free culture. IL-4 alone did not support mixed colony formation in the presence of erythropoietin (Epo). However, IL-4 showed weak but significant BPA when peripheral blood (PB)-derived CD34⁺c-kit^low cells were used as the target population. The BPA of IL-4 was much weaker than that of IL-3, which exerted the most potent activity, as previously reported. When CD34⁺c-kit^high cells were used as the target, four factors known to have BPA, IL-3, GM-CSF, IL-9 and SCF, could express BPA. In contrast, IL-4 alone failed to support erythroid burst formation. Interestingly, IL-4 showed a remarkable enhancing effect with SCF in promoting the development of erythroid burst and erythrocyte-containing mixed colonies from CD34⁺c-kit^low and CD34⁺c-kit^high cells. Delayed addition of SCF + Epo or IL-4+Epo to the cultures initiated with either IL-4 or SCF alone clearly demonstrated that SCF was a survival factor for both BFU-E and CFU-Mix progenitors. In contrast, the survival effect of IL-4 was much weaker than that of SCF, and appeared to be more important for progenitors derived from CD34⁺c-kit^low cells than for those derived from CD34⁺c-kit^high cells. It was recently reported that CD34⁺c-kit^low cells represent a more primitive population than CD34⁺c-kit^high cells. Taken together, these results suggest that IL-4 helps to recruit primitive progenitor cells in the presence of SCF.     

CD4+CD25+CD127low/-T淋巴细胞在类风湿关节炎患者外周血中的表达及意义

目的 检测调节性T淋巴细胞新旧标志在活动性类风湿关节炎(RA)患者外周血中的表达,探讨用CD127代替FOXP3对调节性T淋巴细胞进行研究的可能性.方法 选取活动性RA患者32例,其中未经缓解病情抗风湿药(DMARDs)治疗者20例,经DMARDs治疗效果不佳者12例,以25例原发性干燥综合征(pSS)患者和24名健康人作为对照,采用流式细胞术检测外周血中CD4+CD25high、CD4+CD25+CD127low/-及CD4*CD25+FOXP3+T淋巴细胞的比例,同时检测外周血C反应蛋白(CRP)、红细胞沉降率(ESR)、免疫球蛋白、补体等水平并进行相关性分析.结果 RA患者CD4+CD25highT淋巴细胞百分率与健康对照组相比差异无统计学意义(P>0.05).其CD4+CD25+FOXP3+T淋巴细胞与CD+CD25+CD127low/-T淋巴细胞的百分率均低于健康对照组(P<0.05),但CD4+D25+FOXP3+、CD4+CD25+CD127low/-T淋巴细胞在RA患者与pSS患者中的表达差异无统计学意义(P>0.05);这三群细胞的表达水平在RA未经治疗组和治疗效果不佳组之间差异均无统计学意义(P>0.05). RA患者CD4+CD25+FOXP3+T淋巴细胞与CD4+CD25+CD127low/-T淋巴细胞之间呈明显正相关(r=0.698,P=0.001),但这两群细胞与患者的CRP、ESR等水平及抗环瓜氨酸肽(CCP)抗体、类风湿因子(RF)均无相关性(P>0.05).结论 活动性RA患者外周血中,CD4+CD25+CD127low/-T淋巴细胞的百分率降低,并且与CD4+CD25+FOXP3+T淋巴细胞呈显著正相关性,提示CD127可能被作为Treg细胞中FOXP3的替代标记.