复发性自然流产患者外周血自然杀伤细胞免疫表型检测

目的 检测复发性自然流产(RSA)患者外周血自然杀伤(NK)细胞的免疫表型。方法 应用流式细胞术检测27例RSA妊娠患者、41例RSA非妊娠患者、32例正常妊娠者和25例正常非妊娠者外周血CD56dimCD 16+、CD56brightCD16+/-、CD69+、HLA-DR+ NK细胞表达并进行比较。结果RSA妊娠组、RSA非妊娠组、正常妊娠组和正常非妊娠组外周血CD56dimCD16+ NK细胞占总NK细胞的比例分别为(88.69.±5.86)％、(79.25±9.31)％、(79.24±10.09)％、(75.49±11.96)％;CD56brightCD16+/- NK细胞的比例分别为(8.18±5.54)％、( 12.20±6.49)％、( 13.13±8.65)％、( 11.53±6.23)％;CD69+ NK细胞的比例分别为(3.42±2.13)％、(2.36±1.72)％、(2.68±1.81)％、(2.08±1.73)％;HLA-DR+ NK细胞的比例分别为(15.26±9.32)％、(9.96±7.18)％、( 10.57±8.05)％、(9.64±6.12)％。与RSA非妊娠组、正常妊娠组及正常非妊娠组比较,RSA妊娠组CD56dimCD16+、CD69+、HLA-DR+ NK细胞显著升高（均P＜0.05）。与RSA非妊娠组及正常妊娠组比较,RSA妊娠组CD56brightCD16+/- NK细胞明显降低（均P＜0.05）。结论 RSA妊娠患者外周血中NK细胞CD56dimCD16+、CD69+和HLA-DR+表达增高,而CD56brightCD16+/-表达下降,可能在RSA的发生发展中起着一定的作用。     

结核性胸液中NK细胞的亚群及表型功能特征分析

目的探讨结核性胸液(PFC)中NK细胞的亚群分布及表型功能特征。方法以正常人外周血单个核细胞(PBMC)作对照,利用多种标记抗体进行表面和细胞内细胞毒效应分子染色,再利用流式细胞仪在单个细胞水平上分析结核性胸水中NK细胞亚群的异质性和生物学特征。结果 NK细胞可以分为CD56+CD16-、CD56+CD16+和CD56-CD16+三个亚群,与PBMC中的NK细胞相比,PFC中CD56+CD16-NK细胞亚群明显增加,而CD56+CD16+NK细胞亚群比例明显下降;结核性胸液中CD56+CD16-及CD56+CD16+NK细胞亚群表达较低水平的颗粒酶B,CD107a/b的比例在结核性胸液中3个NK细胞亚群中均有增加(P<0.05)。结核性胸液中NK细胞表达高水平表面抑制性受体NKG2A及表面活化性受体NKG2D。活化分子CD69及CD25在结核性胸水中NK细胞上的表达均有所增加(P<0.05)。结论结核性胸液中的NK细胞比例与PBMC相比发生变化,结核性胸液中的NK细胞表达低水平杀伤分子颗粒酶B但表达高水平活化分子CD69,提示NK细胞在结核感染中发挥其生物学功能。     

乏氧对人外周血NK细胞NKG2A、NKG2D及CD44表达的影响

目的： 观察乏氧微环境对人外周血自然杀伤细胞(NK)表面自然杀伤细胞2族成员A(NKG2A)、自然杀伤细胞2族成员D(NKG2D)及CD44分子表达的影响,探讨乏氧抑制NK细胞杀伤活性的分子机制。方法: 采用密度梯度离心法分离健康人外周血单个核细胞（PBMC）,贴壁去除单核细胞获得外周血淋巴细胞（PBL）,分别置常氧（21％O2）、乏氧（1％O2）以及有或无人重组白细胞介素2(rhIL-2)（1×106 U/L）刺激条件下培养16 h,流式细胞术（FCM）检测不同 NK细胞亚群 NKG2A、NKG2D以及CD44分子的表达。结果: 常氧条件,人外周血CD3-CD56+NK细胞NKG2A、NKG2D表达的阳性率分别为16.16%和78.45%,乏氧条件下二者表达的阳性率分别为15.16%和71.08%;rhIL-2上调NKG2A和NKG2D的表达,乏氧不影响 rhIL-2对NKG2D、 NKG2A的上调作用;rhIL-2显著上调NK细胞CD44的表达,乏氧抑制CD44的表达（P<0.05）。结论: 乏氧下调外周血NK细胞表面受体NKG2D及CD44的表达,但对NKG2A的表达无显著影响。由此提示,NKG2D及CD44分子可能在乏氧引起的NK细胞杀伤活性抑制中具有重要作用。     

妊娠早期蜕膜CD56~+NK样细胞杀伤活性的研究

分离早孕妇女蜕膜CD56~+NK样细胞,采用改进的乳酸脱氢酶(LDH)释放试验,比较蜕膜与外周血NK细胞杀伤活性。结果发现:蜕膜NK样细胞杀伤活性低于孕妇外周血及正常育龄妇女外周血NK细胞。提示妊娠早期蜕膜局部NK细胞活性受到抑制,可能有利于滋养细胞侵袭和胎盘形成。     

CD226在NK细胞亚群上表达规律与功能关系的研究

目的：观察CD226分子在NK细胞亚群上的分布和其他NK细胞活化性受体和抑制性受体的共存规律，及与NK细胞功能的关系。方法：分别以IL-2或IL-15刺激PBMC和MLC细胞为模型，采用双重免疫荧光染色和流式细胞术分析，观察CD226分子在CD56^bright和CD56^dim NK细胞亚群上的表达，及与NK细胞活化性受体CD16和抑制性受体NKG2A的共存关系，同时用ELISA方法检测培养上清中IFN-γ的水平。用4小时^51Cr释放试实验检测NK细胞杀伤水平。结果：在PBMC中，CD226主要分布于CD56^dim亚群，在IL-2作用下，CD226主要分布于CD56^bright,亚群，而在IL-15作用下，NKG2A^ CD226^ 双阳性细胞明显增加。在MLC活化的NK细胞中，CD226主要分布于CD56^dim亚群，在IL-15作用下，CD226主要分布于CD56^bright亚群，IL-2和IL-15都能促进CD16^ CD226^ 和NKG2A^ CD226^ 双阳性细胞的增殖。IL-2和IL-15能明显提高PBMC培养上清中IFN-γ的水平，并能促进PBMC和MLC中NK细胞的杀伤活性。结论：CD226主要分布于活化NK细胞CD56^bright群上，其表达水平及与CD16及NKG2A共存关系可能受不同细胞因子调节并与NK细胞功能相关。     

人早孕期蜕膜基质细胞对蜕膜NK细胞分泌IL-22的调节作用

目的:探讨蜕膜基质细胞(Decidual stromal cells,DSCs)与蜕膜NK细胞(dNK)共培养后IL-22的分泌水平。方法:收集早孕蜕膜组织,分离蜕膜基质细胞(DSCs)及蜕膜免疫活性细胞(Decidual immunocytes,DICs),磁珠分选蜕膜CD56brightCD3-NK细胞,再与DSC按不同比例直接接触共培养(dNK∶DSC为1∶1、1∶2、1∶3)24小时,收集上清。ELISA检测上清中IL-22的表达。结果:与对照组相比,DSC能上调dNK分泌IL-22。结论:蜕膜基质细胞可以促进蜕膜NK细胞分泌IL-22。     

重度子痫前期蜕膜NK细胞Tim-3的表达及其相关作用

目的 探讨重度子痫前期Tim-3+CD56+CD16-NK细胞的表达及其对滋养细胞侵袭及血管内皮细胞成管能力的影响.方法 分离重度子痫前期患者(sPE组)及正常妊娠孕产妇(Normal组)的胎盘蜕膜组织中单个核细胞,细胞流式检测蜕膜NK细胞(decidual NK cell,dNK)细胞所占比例;免疫磁珠分选CD56+...     

急性非淋巴细胞白血病患者NK细胞亚群及其NCR受体测定

目的： 探讨初发的急性非淋巴细胞白血病患者NK细胞亚群分布及自然细胞毒受体（NCR）的水平。方法：应用流式细胞仪技术测定26例初发急性非淋巴细胞白血病患者外周血NK细胞、NK细胞亚群、自然细胞毒受体。结果： 初发急性非淋巴细胞白血病患者外周血NK细胞明显低于对照组（P<0.01），CD56bright及CD56dimNK细胞明显低于正常对照组（P<0.01），NKp30、NKp44、NKp46在CD56+CD3-细胞中的表达均低于正常对照组（P<0.05）。结论： 急性非淋巴细胞白血病发病可能与NK细胞及亚群减低，自然细胞毒受体表达降低有关。     

人早孕期蜕膜基质细胞下调蜕膜NK细胞杀伤活性

通过分析人早孕期蜕膜基质细胞(decidual stromal cell,DSC)对蜕膜NK细胞(dNK)表面趋化因子受体CXCR4与细胞内颗粒酶B表达水平的影响,研究早孕蜕膜基质细胞对局部NK细胞的训导作用。收集早孕蜕膜组织,分离DSC及蜕膜免疫活性细胞,进一步通过磁珠分选蜕膜CD3-CD56bright NK细胞,将分离的蜕膜NK细胞与DSC按1∶1比例共培养24h,收集蜕膜NK细胞,流式细胞仪检测其表面趋化因子受体CXCR4和细胞内颗粒酶B(granzyme B)的表达水平。结果显示,与对照组相比,在与DSC细胞共培养之后,趋化因子受体CXCR4+NK细胞的百分率明显上升,而蜕膜NK细胞内颗粒酶B阳性率显著下降(P<0.05)。结果表明,人早孕母-胎界面DSC细胞上调蜕膜NK细胞表面趋化因子受体CXCR4的表达,下调NK细胞内颗粒酶B的表达水平,可能抑制其杀伤活性。     

人早孕蜕膜基质细胞及免疫活性细胞趋化因子受体CXCR6的表达

目的分析人早孕期蜕膜基质细胞趋化因子配基受体对CXCL16/CXCR6的表达及免疫活性细胞趋化因子受体CXCR6的表达,以探讨CXCL16/CXCR6在蜕膜免疫活性细胞募集中的可能规律.方法收集早孕期蜕膜组织,分离蜕膜基质细胞和免疫细胞,分别采用半定量RT-PCR、免疫细胞化学、流式细胞术分析蜕膜基质细胞CXCL16和CXCR6的表达;流式细胞术分析蜕膜CD56^＋CD16^-NK细胞、CD56^＋CD16^＋NK细胞、NKT细胞、T细胞、γδT细胞、单核细胞CXCR6的表达.结果人早孕蜕膜基质细胞高水平转录趋化因子受体CXCR6,低水平转录其配体CXCL16,但CXCL16和CXCR6在蛋白水平的表达偏低.早孕蜕膜γδT细胞CXCR6阳性率为87.29%;CD14^＋单核细胞CXCR6阳性率为47.71%;NKT细胞CXCR6阳性率为44.14%;T细胞CXCR6表达率为32.91%;而蜕膜两种NK细胞（CD56^＋CD16^-、CD56^＋CD16^＋）几乎不表达CXCR6.结论人γδT细胞、单核细胞、NKT细胞、T细胞可能通过表达趋化因子受体CXCR6被募集到蜕膜局部并驻留,从而参与早孕期母胎界面的免疫调节.     

Expression of natural cytotoxicity receptors and a2V-ATPase on peripheral blood NK cell subsets in women with recurrent spontaneous abortions and implantation failures

PROBLEM: Natural cytotoxicity receptors (NCRs) are unique markers, which regulate NK cell cytotoxicity and cytokine production. a2V-ATPase is expressed on subsets of PBMC and regulates the extracellular environment, which facilitates NK cytotoxicity or cytokine secretion. In this study, we aim to investigate the expression of NCRs and a2V-ATPase in peripheral blood NK cells of women with recurrent spontaneous abortions (RSA) or implantation failures. METHOD OF STUDY: Peripheral blood NK cells (CD56(dim) and CD56(bright) were analyzed for the expression of NCRs (NKp46, NKp44 and NKp30) and a2V-ATPase using 3-color flow cytometry in women with RSA (n=24), implantation failures (n=19) or normal healthy women (n=13). RESULTS: CD56+/NKp46+ cells were markedly decreased (P<0.05) and CD56(bright)/a2V-ATPase+ cells were significantly increased (P<0.05) in women with RSA as compared to those of normal controls. In women with RSA or implantation failures, expression of NKp46, NKp44, NKp30, and a2V-ATPase on CD56(bright) NK cells was significantly up-regulated as compared with those of CD56(dim) NK cells. CONCLUSION: The differential expression of NCRs and a2V-ATPase in NK cell subsets may suggest dysregulation of NK cytotoxicity and cytokine production in women with RSA and implantation failures.     

Histone deacetylase inhibitors impair NK cell viability and effector functions through inhibition of activation and receptor expression

HDACi are being used as a novel, therapeutic approach for leukemias and other hematological malignancies. However, their effect on immune cells remains ill-defined, as HDACi may impair immune surveillance. In this work, we demonstrate that TSA, VPA, and NaB inhibited IFN-γ production by CD56(dim) and CD56(bright) NK cells and NK cell-mediated cytotoxicity against K562 target cells. HDACi promoted minor NK cell apoptosis but inhibited nuclear mobilization of NF-κB p50, which was accompanied by a robust down-regulation of NKG2D and NKp46 on resting NK cells and of NKG2D, NKp44, NKp46, and CD25 on cytokine-activated NK cells. Decreased CD25 expression promoted a weakened IFN-γ secretion upon restimulation of NK cells with IL-2, whereas reduced expression of NKG2D and NKp46 was accompanied by an impaired NKG2D- and NKp46-dependent cytotoxicity. Moreover, NK cells from normal mice treated in vivo with TSA displayed a diminished expression of NK1.1, NKG2D, and NKp46 and secreted reduced amounts of IFN-γ upon ex vivo stimulation with cytokines. Thus, our preclinical results indicate that HDACi exert deleterious effects on NK cell function, which may weaken immune surveillance and facilitate relapse of the malignant disease in HDACi-treated patients.     

Increased expressions of NKp44, NKp46 on NK/NKT-like cells are associated with impaired cytolytic function in self-limiting hepatitis E infection

We have characterized the NK/NKT-like cells in patients with self-limiting hepatitis E infection. The distribution of peripheral NK/NKT-like cells, expressions of activation receptors, cytotoxic potential and effector function of NK/NKT-like cells from fresh peripheral blood mononuclear cells of 86 acute patients, 101 recovered and 54 control individuals were assessed. Activated NKT-like (CD16⁺ CD56⁺ CD3⁺) cells were high in the patient groups. On CD56⁺ CD3^? cells, NKp44 and NKp46 expressions were high in the acute patients, whereas NKp30, NKp44, NKp46 and NKG2D were high in the recovered individuals. On CD56⁺ CD3⁺ cells, NKp44, NKp46 and NKG2D expressions were high in the recovered but NKp30 was low in both the patient groups. Collectively, the current study elucidates the role of NK/NKT-like cells demonstrating phenotypic alterations of activated NKT-like cells and activation receptors, lack of CD107a expression and functional impairment of peripheral NK/NKT-like cells in self-limiting hepatitis E infection.     

Age-related changes in natural killer cell receptors from childhood through old age

Most studies on natural killer (NK) cells and aging have focused on overall cell numbers and global cytotoxic activity. NK cell functions are controlled by surface receptors belonging to three major families: killer cell immunoglobulin-like receptors (KIRs), natural cytotoxicity receptors (NCRs), and C-type lectins. The expression of these receptors was investigated from childhood through old age in T, NKT- and NK cells and also in the CD56(dim) (cytotoxic) and CD56(bright) (responsible for cytokine production) NK cell subsets. A decrease in the expression of activating receptors (NKp30 and NKp46) was observed in NK cells in elderly individuals. KIR expression was increased only in the CD56(bright) subset. Children presented similar results regarding expression of NKp30 and KIR, but not NKp46. NKG2D expression was decreased in T cells of elderly subjects. Analysis of KIR genotype revealed that KIR2DL5 and KIR2DS3 were significantly associated with old age. Cytotoxic activity was preserved from childhood through old age, suggesting that the increase of the absolute number of CD56(dim), observed in elderly, may represent a compensatory mechanism for the receptor expression alterations. This initial study provides the framework for more focused studies of this subject, which are necessary to determine whether the changing balance of NK receptor expression may influence susceptibility to infectious, inflammatory, and neoplastic diseases.     

CD59 is physically and functionally associated with natural cytotoxicity receptors and activates human NK cell-mediated cytotoxicity

Triggering of cytotoxicity in human NK cells is induced by the combined engagement of several triggering receptors. These include primary receptors such as NKG2D and the natural cytotoxicity receptors (NCR) NKp30, NKp46 and NKp44, while other molecules, including 2B4, NTB-A and NKp80, function as co-receptors. As reported in the present study, during an attempt to identify novel NK receptors or co-receptors, we found that CD59 functions as a co-receptor in human NK cell activation; engagement of CD59 by specific mAb delivers triggering signals to human NK cells, resulting in enhancement of cytotoxicity. Similar to other NK co-receptors, the triggering function of CD59, a glycosylphosphatidylinositol (GPI)-linked protein, depends on the simultaneous engagement of primary receptors such as NCR. Accordingly, CD59-dependent triggering was virtually restricted to NK cells expressing high surface densities of NKp46, and mAb-mediated modulation of NKp46 resulted in markedly decreased responses to anti-CD59 mAb. Biochemical analysis revealed that CD59 is physically associated with NKp46 and NKp30. Moreover, engagement of CD59 resulted in tyrosine phosphorylation of CD3zeta chains associated with these NCR, but not those associated with CD16. Thus, CD59-mediated costimulation of NK cells requires direct physical interaction of this GPI-linked protein with primary triggering NK receptors.     

Expression of killer immunoglobulin-like receptors on peripheral blood NK cell subsets of women with recurrent spontaneous abortions or implantation failures

PROBLEM: Decidual natural killer (NK) cells express inhibitory receptors (killer immunoglobulin-like receptors, KIRs), which bind to ligands on trophoblast cells (human leucocyte antigen, HLA-C). This interaction appears to block NK cytotoxicity against trophoblast cells. In this study, we investigated the expression of inhibitory and activating receptors in peripheral blood NK cells of women with recurrent spontaneous abortion (RSA) or implantation failures. METHOD OF STUDY: CD56(dim)/CD16(+), CD56(bright)/CD16(-) NK cells and CD56(+)/CD3(+) NKT cells of women with RSA or in vitro fertilization (IVF) failures and normal controls were analyzed for the expression of CD158a, CD158b inhibitory KIRs or CD161-activating receptors, by flow cytometric analysis. RESULTS: CD158a and CD158b inhibitory receptor expression by CD56(dim)/CD16(+) and CD56(bright)/CD16(-) NK cells were significantly decreased, and CD161-activating receptor expression by CD56(+)/CD3(+) NKT cells was significantly increased in women with implantation failures when compared with normal controls. CONCLUSIONS: An imbalance between inhibitory and activating receptor expression was found in NK cells of women with implantation failures. This imbalance may explain the adverse reproductive outcome.     

Increased proportion of CD56bright natural killer cells in active and inactive systemic lupus erythematosus

Natural killer (NK) cells belong to the innate immune system but can also affect adaptive immune reactions. This immune regulatory function is often ascribed to the CD56(bright) subpopulation of NK cells that is prevalent in secondary lymphoid tissues and has potent cytokine-producing ability. The NK cells have been described as affecting autoimmune disease and stimulating B-cell production of antibodies, but their role in systemic lupus erythematosus (SLE) pathology has not been extensively studied. We have studied NK cells in SLE, a B-cell-driven systemic autoimmune disease, and phenotypically characterized peripheral blood NK cells in comparison to NK cells from patients with immunoglobulin A nephritis, rheumatoid arthritis and healthy individuals. We have found an increased proportion of CD56(bright) NK cells in SLE, regardless of disease activity. We detected a somewhat increased expression of the activating receptor NKp46/CD335 on NK cells from SLE patients, although neither the percentage of NK cells of all lymphocytes nor the expression of other NK receptors analysed (LIR-1/CD85j, CD94, NKG2C/CD159c, NKG2D/CD314, NKp30/CD337, NKp44/CD336, CD69) differed between patient groups. We show that type I interferon, a proinflammatory cytokine known to be abundant in SLE, can cause increases of CD56(bright) NK cells in vitro. We confirmed that serum levels of interferon-alpha were increased in active, but not in inactive, disease in the SLE patient group. In conclusion, we found an increased proportion of CD56(bright) NK cells in the blood of SLE patients, although it remains to be examined whether and how this relates to the disease process.     

Peritoneal natural killer cells from epithelial ovarian cancer patients show an altered phenotype and bind to the tumour marker MUC16 (CA125)

The ovarian tumour marker MUC16 (CA125) inhibits the cytotoxic responses of human natural killer (NK) cells and down-regulates CD16. Here we show that approximately 10% of the peripheral blood NK cells (PBNK) from the epithelial ovarian cancer (EOC) patients are CD16(-) CD56(br) whereas 40% of the peritoneal fluid NK (PFNK) carry this phenotype, which is usually associated with NK cells from the lymph nodes or human decidua. PBNK from healthy donors exposed to PF show a significant increase in the CD16(-) CD56(br) population. This shift in phenotype is not caused by increased apoptosis of the CD16(+) CD56(dim) cells or selective proliferation of the CD16(-) CD56(br) NK cells. Thus, the terminal differentiation of the CD16(-) CD56(br) NK cells to CD16(+) CD56(dim) subset that occurs during normal NK cell development may actually be a reversible step. A majority of the NK cell receptors (NKp46, NKp44, NKG2D, CD244, CD226, CD158a, CD158b, and CD158e) studied were down-regulated in the PFNK. MUC16 binds selectively to 30-40% of CD16(+) CD56(dim) NK cells in EOC patients indicating that phenotypic alterations in these cells are mediated by tumour-derived soluble factors. Similar to EOC, MUC16 in early pregnancy also binds to NK cells suggesting shared mechanisms of NK cell suppression in feto-maternal tolerance and immune evasion by ovarian cancers.