急性髓系白血病细胞血管细胞黏附分子1、CD34和CD117的表达

背景：血管细胞黏附分子1与白血病浸润密切相关,白血病细胞本身是否表达血管细胞黏附分子1,以及与疾病难治是否相关尚无定论。目的：分析血管细胞黏附分子1、CD34、CD117在急性髓系白血病细胞表面的表达,3者之间的相互关系及与难治性急性髓系白血病的相关性。方法：采用流式细胞技术检测16例急性髓系白血病细胞中血管细胞黏附分子1、CD34、CD117的表达,其中难治组6例,非难治组10例;同时以正常骨髓单个核细胞标本作对照。结果与结论：急性髓系白血病细胞CD34、CD117表达高于对照组（P〈0.05）。难治组急性髓系白血病细胞CD34表达明显高于非难治组（P〈0.05）。难治组与非难治组CD117表达差异无显著性意义（P〉0.05）。急性髓系白血病细胞血管细胞黏附分子1表达与对照组比较差异无显著性意义（P〉0.05）。难治组与非难治组血管细胞黏附分子1表达差异无显著性意义（P〉0.05）。表明急性髓系白血病细胞伴CD34表达,为不良预后指标之一,CD117、血管细胞黏附分子1表达与其是否难治无明显相关性。     

CD3~+CD56~+NKT样细胞在急性白血病患者体内表达的研究

目的探讨CD3+CD56+NKT样细胞在急性白血病患者治疗前后体内的表达情况。方法分别取急性白血病(急性髓系白血病43例,急性淋巴细胞白血病12例,急性混合细胞白血病5例)及非恶性肿瘤(10例)患者骨髓血2ml送流式细胞仪检测,比较白血病患者治疗前后及非恶性肿瘤患者体内CD3+CD56+NKT样细胞的表达情况。结果急性白血病患者初治组与非恶性肿瘤患者对照组间比较,急性白血病患者骨髓中CD3+CD56+NKT样细胞比例明显比对照组低(P0.01);急性白血病患者治疗后骨髓中CD3+CD56+NKT样细胞比例明显比治疗前高(P0.01),且与缓解程度及时间呈正相关;急性白血病患者治疗后骨髓中CD3+CD56+NKT样细胞比例与非恶性肿瘤对照组比较无统计学意义(P0.05);不同类型白血病之间,急性早幼粒细胞白血病治疗后CD3+CD56+NKT样细胞比例明显较其他类型高(P0.05),急性髓系白血病(除M3外)与急性淋巴细胞白血病之间比较CD3+CD56+NKT样细胞比值结果比较无统计学意义(P0.05)。结论急性白血病患者CD3+CD56+NKT样细胞反映了机体的免疫功能,化疗后CD3+CD56+NKT样细胞明显增多可能是预后较好的标志之一。     

CD117在白血病细胞上的表达分析

目的　探讨细胞表面分化抗原CD117在各型白血病细胞上的表达规律及其意义。方法　采用CD4 5/SSC双参数散点图设门方法进行三色流式细胞术细胞表面分化抗原分析。结果　急性髓系白血病 (AML)患者CD117表达率为 6 8%,慢性粒细胞白血病急变期 (CML BC)患者CD117表达率为 80 %,而在急性淋巴细胞白血病中表达率极低 ,仅为 2 %。在慢性淋巴细胞白血病、CML慢性期中阴性。在AML中CD117主要表达在M0 /M1( 72 %)、M2 ( 88%)、M4 ( 5 0 %)、M5a( 75 %)、M6( 10 0 %) ,但在M3 和M5b中表达率较低 (分别为 39%和 2 9%) ,在M3 中CD117的表达率高于CD34 及HLA DR。CD117与CD14 在AML中的表达呈负相关。结论　CD117有助于淋巴系与髓系白血病的鉴别 ,并有助于白血病克隆与正常细胞的区分。     

急性髓细胞性白血病患者外周血单个核细胞CD28 mRNA的表达

背景：大量研究显示,肿瘤患者外周血T细胞表面共刺激分子CD28蛋白表达存在差异,提示共刺激通路异常可能与恶性肿瘤的发生进展有关。目的：观察急性髓细胞性白血病外周血单个核细胞共刺激信号分子CD28 mRNA在中的表达。方法：急性髓细胞性白血病患者80例,其中M0型7例,M1型6例,M2型18例,M3型15例,M4型17例,M5型9例,M6型8例。并根据急性白血病疗效标准将80例患者分为完全治愈组、缓解组、未缓解组。采用Taqman探针实时荧光定量PCR检测80例患者及76名健康人群外周血单个核细胞CD28 mRNA的表达。结果与结论：急性髓细胞性白血病外周血单个核细胞M1,M3和M4亚型中的CD28 mRNA表达量低于健康人群（P〈0.05）;急性髓细胞性白血病未缓解组中CD28 mRNA低于健康人群（P〈0.05）,完全治愈组和缓解组中CD28 mRNA表达与健康人群差异无显著性意义。说明急性髓细胞白血病患者外周血单个核细胞存在CD28 mRNA表达缺陷,并与临床分期、病情进展及预后有关。     

CDll7在白血病细胞上的表达分析

目的 探讨细胞表面分化抗原CD117在各型白血病细胞上的表达规律及其意义。方法 采用CD45／SSC双参数散点图设门方法进行三色流式细胞术细胞表面分化抗原分析。结果急性髓系白血病(AML)患CD117表达率为68％，慢性粒细胞白血病急变期(CML-BC)患CD117表达率为80％，而在急性淋巴细胞白血病中表达率极低，仅为2％。在慢性淋巴细胞白血病、CML慢性期中阴性。在AML中CD117主要表达在M0／M1(72％)、M2(88％)、M4(50％)、M5b(75％)、M6(100％)，但在M3和M5b中表达率较低(分别为39％和29％)，在从中CD1l7的表达率高于CD54及HLA—DR。CD117与CD14在AML中的表达呈负相关。结论 CD117有助于淋巴系与髓系白血病的鉴别，并有助于白血病克隆与正常细胞的区分。     

CD7在急性白血病中的表达及临床意义的探讨

目的　探讨CD7在急性白血病中的表达及临床意义。方法　采用流式细胞术微量全血直接标记法测定32例急性白血病患者细胞表面抗原,分析 CD7 分子在其中的表达。结果　CD7分子在急性淋巴细胞性白血病(ALL)和急性髓细胞性白血病(AML)均可表达,两者阳性数无显著性差异(P<0.01);20例AML中有5例可见CD7 、CD34共表达,主要分布于M0、M1、M4和 M5;CD7阳性AML、CD7阳性ALL的外周血白细胞数均高于CD7阴性AML和CD7阴性ALL (P<0.01)。结论　CD7在AML 、ALL中均可表达,对CD7阳性AML应结合CD34、CD79a等指标综合考虑。     

老年初诊急性髓细胞白血病患者CD4+CD25+调节性T细胞的表达

背景：研究证实,很多恶性肿瘤患者体内CD4+CD25+调节性T细胞存在高表达,近期也有研究发现,急性髓细胞白血病患者外周血CD4+CD25+目的：分析老年初诊急性髓细胞白血病患者CD4调节性T细胞同样表现出高比例表达。+CD25+方法：纳入初诊急性髓细胞白血病患者92例,将年龄在60岁以下者设为中青年组(n=22),年龄在60岁以上者设为老年观察组(n=70)。在老年观察组中,32例经规范化疗后完全缓解,设为完全缓解组;将余下38例设为老年组,依据FAB分型标准,分为M26例、M319例、M47例、M56例。另选择同期体检健康人群42名作为正常对照组。抽取受试者外周静脉血,检测CD4调节性T细胞的表达特点。+CD25+结果与结论：老年组、完全缓解组CD4调节性T细胞表达情况。+CD25highFOXP3+调节性T细胞比例高于正常对照组(P <0.01),并且老年组CD4+CD25highFOXP3+调节性T细胞比例高于完全缓解组(P <0.01)。老年组、完全缓解组CD4+FOXP3+T细胞比例高于正常对照组(P <0.01),并且老年组CD4+FOXP3+T细胞比例高于完全缓解组(P<0.01)。老年组CD4+CD25highFOXP3+调节性T细胞与CD4+ FOXP3+T细胞比例高于中青年组(P <0.01)。老年组不同分型间CD4+CD25high FOXP3+调节性T细胞和CD4+ FOXP3+T细胞比例比较差异均无显著性意义(P >0.05)。Pearson相关性检验结果显示,老年初诊急性髓细胞白血病患者外周血CD4+CD25high FOXP3+调节性T细胞比例和CD4+ FOXP3+T细胞比例呈正相关(r=0.87,P=0.019)。表明老年初诊急性髓细胞白血病患者CD4+CD25+调节性T细胞比例高于健康人群和中青年急性髓细胞白血病患者。     

CD34抗原在急性双表型白血病的临床研究

本研究旨在探讨白细胞CD34抗原在急性双表型白血病（biphenotypic acute leukemia,BAL）的表达情况,以明确其与BAL预后的关系.应用流式细胞仪检测白血病相关抗原,所用单克隆抗体B淋巴细胞系列为CD10,CD19和CD34;T淋巴细胞系列为CD2,CD3和CD5;髓系为MPO,CD13和CD33,最终对结果进行分析.结果表明：216例急性白血病患者中9例（4.2％）被诊断为急性双表型白血病,其中髓系和B淋巴细胞系共同表达6例（66.7％）,髓系和T淋巴细胞系共同表达3例（33.3％）.4例CD34表达阳性（44.4％）与急性髓系白血病和急性淋巴细胞白血病相比,双表型急性白血病患者表现出显着较高的CD34抗原阳性表达率（P＜0.05）.结论：与急性髓细胞性白血病或急性淋巴细胞白血病相比,急性双表型白血病患者的预后较差,CD34阳性表达可能与急性双表型白血病的治疗效果呈负相关.     

急性髓细胞性白血病患者外周血单个核细胞CD28mRNA的表达

背景:大量研究显示,肿瘤患者外周血T细胞表面共刺激分子CD28蛋白表达存在差异,提示共刺激通路异常可能与恶性肿瘤的发生进展有关.目的:观察急性髓细胞性白血病外周血单个核细胞共刺激信号分子CD28 mRNA在中的表达.方法:急性髓细胞性白血病患者80例,其中M0型7例,M1型6例,M2型18例,M3型15例,M4型17例,M5型9例,M6型8例.并根据急性白血病疗效标准将80例患者分为完全治愈组、缓解组、未缓解组.采用Taqman探针实时荧光定量PCR检测80例患者及76名健康人群外周血单个核细胞CD28 mRNA的表达.结果与结论:急性髓细胞性白血病外周血单个核细胞M1,M3和M4亚型中的CD28 mRNA表达量低于健康人群 (P < 0.05);急性髓细胞性白血病未缓解组中CD28 mRNA低于健康人群 (P < 0.05),完全治愈组和缓解组中CD28 mRNA表达与健康人群差异无显著性意义.说明急性髓细胞白血病患者外周血单个核细胞存在CD28 mRNA表达缺陷,并与临床分期、病情进展及预后有关.     

NVP-BEZ235抑制CD34~+CD38~-急性髓系白血病干细胞的增殖和集落形成

本研究旨在探讨PI3K/mTOR信号系统双靶点抑制剂———NVP-BEZ235对CD34+CD38-髓系白血病干细胞增殖、细胞周期和集落形成能力的影响。用流式细胞术检测急性髓系白血病KG1a细胞表面CD34和CD38的表达;应用台盼蓝染色细胞计数法检测不同浓度NVP-BEZ235对KG1a细胞增殖的影响,PI染色流式细胞术检测NVP-BEZ235对KG1a细胞周期的影响,持续用软琼脂集落形成实验检测不同浓度NVP-BEZ235对KG1a细胞集落形成细胞的影响。结果表明,急性髓系白血病KG1a细胞中CD34+CD38-占(98.02±0.72)%,NVP-BEZ235(0.125-1μmol/L)对KG1a细胞增殖抑制呈现时间和剂量依赖(P<0.05),其24和48 h的IC50值分别为0.597和0.102μmol/L。0.5μmol/L的NVP-BEZ235作用24 h后,G0/G1期KG1a细胞比例达(83.2±3.80)%,较对照组(43.47±9.60)%明显增高(P<0.05)。2500个细胞在NVP-BEZ235(0-1μmol/L)持续作用下14 d和21 d而形成的集落数分别由375.67±21.46、706.33±87.31降至0(P<0.05)。结论:NVP-BEZ235能抑制CD34+CD38-髓系白血病干细胞增殖和集落形成。     

CD137 enhances cytotoxicity of CD3CD56 cells and their capacities to induce CD4 Th1 responses

CD137 (4-1BB) is a TNFR superfamily member that mediates the costimulatory signal resulting in T cells and NK cells proliferation and cytokines production, but the effects of CD137 signaling on CD3⁺CD56⁺ cell subpopulation have not been well-documented. The aim of this study was to investigate the effects of CD137 signaling on regulation of CD3⁺CD56⁺ cell function. Anti-CD137 mAb or mouse IgG1 isotype control was added to CIK cell culture to determine the effects of proliferation and anti-tumor effects on CD3⁺CD56⁺ cells. We observed that anti-CD137 mAb could dramatically promote proliferation of CIK cells. And CD137–CIK cells and CD3⁺CD56⁺ cell subpopulation within them possessed higher ability to kill tumor cell line A549. The SCID mice engrafted with A549 cells and treated with CD137–CIK cells have prolonged survival. Further studies revealed that the percentages of CD3⁺CD56⁺ cells were elevated significantly in CD137–CIK cells. The expression of NKG2D was up-regulated on CD3⁺CD56⁺ cells from CD137–CIK cells. The expression of IFN-γ, IL-2 and TNF-α increased significantly whereas the production of TGF-β₁, IL-4 and IL-10 decreased in CD3⁺CD56⁺ cells from CD137–CIK cells. In addition, anti-CD137 mAb can elevate the capacity of CD3⁺CD56⁺ cells to induce CD4⁺ Th1 responses. We further showed that the anti-CD137 mAb also had the same effects on CD3⁺CD56⁺ cells expanded from the PBMCs of patients with NSCLC. We concluded that CD137 signaling could enhance the abilities of CIK cells to kill tumor cells in vitro and in vivo via increasing the proportion of CD3⁺CD56⁺ cells and their cytotoxicity. Furthermore, CD137 signaling can elevate the capacity of CD3⁺CD56⁺ cells to induce CD4⁺ Th1 responses which may enhance their anti-tumor activity indirectly. Taken together, our studies could be considered as valuable in CIK cells-based cancer immunotherapy.     

Tyrosine phosphorylation of CD6 by stimulation of CD3: augmentation by the CD4 and CD2 coreceptors

When T cells are activated via the T cell receptor (TCR) complex a number of cellular substrates, including some cell surface proteins, become phosphorylated on tyrosine (Tyr) residues. Phosphorylation of cytoplasmic Tyr renders these cell surface receptors competent to interact with proteins that link cell surface receptors to protein in the intracellular signaling pathways. Here we show that Tyr residues in the cytoplasmic domain of CD6 become phosphorylated upon T cell activation via the TCR complex. Tyr phosphorylation was observed when the T cells were activated by crosslinking CD3 or by cocrosslinking CD3 with CD2 or CD4, but not when the cells were stimulated by crosslinking CD2, CD4, or CD28 alone. Unlike other Tyr kinase substrates, such as the phospholipase C gamma 1-associated pp35/36 protein, whose level of Tyr phosphorylation is highest when T cells are activated by cocrosslinking CD3 with CD2, the levels of CD6 Tyr phosphorylation are highest when T cells were activated by cocrosslinking CD3 with CD4.     

Differential increase of CD34, KDR/CD34, CD133/CD34 and CD117/CD34 positive cells in peripheral blood of patients with acute myocardial infarction

Objective Circulating progenitor cells (CPC) may contribute to cardiac regeneration and neovascularization after acute myocardial infarction (AMI). For potential therapeutic use, understanding the endogenous mechanisms after ischemia is inevitable. We investigated the absolute number, but also the subset composition of CD34+ CPC after AMI. Methods CD34+, KDR+/ CD34+, CD133+/CD34+ and CD117+/CD34+ CPC were analyzed by FACS in peripheral blood of 10 patients with acute MI (59±5 yrs, m/f=8/2) at day of AMI (day 0) and days 1–5. For comparison patients with stable coronary artery disease (CAD, n=12, 66±2 yrs, m/f=10/2) and young healthy volunteers (n=7, 26±2 yrs, m/f=3/4) were studied. Results CD34 and KDR/CD34, CD133/CD34, CD117/CD34 were increased day 3 and 4 after AMI. KDR+ fraction within CD34+ population remained unchanged (58.3±7.8% vs 55.3±10.6%), whereas CD133+ (64.9±3.1% vs 43.5±5.9%, P=0.006) and CD117+ fractions (71.7±5.6% vs 50.1±5.5%, P=0.02) were elevated. In CAD, all CPC and fractions were similar as AMI day 0. Healthy volunteers had more CD34+ than CAD and AMI day 0. Double positive CPC were also higher, but fractions were unchanged vs CAD with more KDR/CD34 in trend (72.8±10.6% vs 50.5±5.6%, P=0.058). After AMI both absolute numbers of CD34+ and their subset composition change, suggesting selective mobilization of CPC. Increased CPC after AMI never reach numbers of young healthy volunteers.     

CD4+CD25+和CD8+调节性T细胞的作用机制

调节性T细胞（Treg）主要在机体免疫系统中发挥负向调节作用,既能抑制不恰当的免疫反应,又能限定免疫应答的范围、程度及作用时间,对CD4^＋和CD8^＋效应性T淋巴细胞的增殖起抑制作用,因此在移植物抗宿主病、自身免疫病、过敏性疾病等的发病机制和临床治疗中有潜在的应用价值.本文重点介绍CD4^＋CD25^＋Treg和CD8^＋Treg的作用机制,并简述调节性T细胞研究面临的挑战与展望.     

Human CD3+ T lymphocytes that express neither CD4 nor CD8 antigens

CD3+ T lymphocytes expressing neither CD4 nor CD8 antigens exist in normal human peripheral blood in low frequency (approximately 3% of lymphocytes). The CD3+,4-,8- phenotype was stably maintained after in vitro culture in IL-2. Culture of CD3+,4-,8- cells in only rIL-2 generated cytotoxic T cells that lysed NK-sensitive and NK-insensitive tumor cell targets without MHC restriction. These experiments clearly show that phenotypically and functionally competent T cells expressing neither CD4 nor CD8 are present in normal peripheral blood.     

CD8alpha- CD11b+ dendritic cells present exogenous virus-like particles to CD8+ T cells and subsequently express CD8alpha and CD205 molecules

Recombinant porcine parvovirus virus-like particles (PPV-VLPs) are particulate exogenous antigens that induce a strong, specific cytotoxic T lymphocyte (CTL) response in the absence of adjuvant. In the present report, we demonstrate in vivo that dendritic cells (DCs) present PPV-VLPs to CD8+ T cells after intracellular processing. PPV-VLPs are captured by DCs with a high efficacy, which results in the delivery of these exogenous antigens to 50% of the whole spleen DC population. In vivo, a few hours after injection, PPV-VLPs are presented exclusively to CD8+ T cells by CD8alpha- DCs, whereas 15 hours later they are presented mainly by CD8alpha+ DCs. After PPV-VLPs processing, a fraction of CD11b+ DCs undergo phenotypic changes, i.e., the up-regulation of CD8alpha and CD205 and the loss of CD4 molecules on their surface. The failure to detect mRNA coding for CD8alpha in CD11b+ DCs suggests that CD8alpha expression by these cells is not due to de novo synthesis. In recombination-activating gene knockout mice (Rag-/-), CD11b+ DCs did not express CD8alpha and PPV-VLPs presentation by CD8alpha+ DCs was severely diminished. These results indicate that both CD8alpha- and CD8alpha+ DCs play an important role in the induction of CTL responses by exogenous antigens, such as VLP.     

Contribution of CD4+, CD8+CD28+, and CD8+CD28- T cells to CD3+ lymphocyte homeostasis during the natural course of HIV-1 infection.

The relationship between the number of circulating CD4+ T cells and the presence of particular CD8+ T cell subsets was analyzed by flow cytometry on PBL from asymptomatic HIV-1-infected patients whose specimens were collected every 2 mo for a total period of 32 mo. Only slight variations were detected in the absolute number of lymphocytes and percentage of CD3+ lymphocytes, whereas both CD4+ and CD8+ T cell subsets showed wide intrapatient variation. Variations in the number of CD8+CD28+ cells paralleled those of the CD4+ T cell subset in each patient tested, while the presence of CD8+CD28- T cells correlated inversely with CD4+ and CD8+CD28+ T cells. These data show that changes in the number of circulating CD4+-and CD8+CD28+ T cells are strongly related to the presence of CD8+CD28- T cells in these patients. Insight into the significance of CD8+CD28- T cell expansion will allow us to understand the mechanisms and significance of the HIV-1- driven change in CD4+CD8+ T cell homeostasis and the basic immunopathology of HIV disease.