KIR2DS1介导同种异体自然杀伤细胞对树突状细胞杀伤作用的研究

目的 研究体外活化性杀伤细胞免疫球蛋白样受体KIR2DS1介导的自然杀伤（NK）细胞对树突状细胞（DC）的杀伤作用,分析体外KIR2DS1阳性的NK细胞与C2表位DC相互作用后C-C趋化因子受体类型7（CCR7）的表达,探究异源反应性NK细胞预防移植物抗宿主病（GVHD）的机制.方法 采集健康人外周血单个核细胞,通过NK细胞分选试剂盒富集NK细胞作为效应细胞;取初诊急性髓系白血病（AML）患者外周血,提取单个核细胞,诱导DC作为靶细胞;通过PCR-序列特异性引物（SSP）基因分型技术和直接测序（SBT）法检测NK细胞和靶细胞KIR基因和人类白细胞抗原（HLA）-Cw基因位点.CCK-8比色法检测KIR2DS1阳性和阴性的NK细胞对DC的杀伤作用;流式细胞术检测与DC作用后NK细胞表面CCR7的表达.结果 流式细胞术检测富集后的NK细胞纯度达（94.20±1.23）％.同一效靶比（10：1）下,KIR2DS1阳性的NK细胞对DC杀伤作用高于KIR2DS1阴性的NK细胞（t=3.70,P＜ 0.05）;同一效靶比（10：1）下,HLA C1/C1组KIR2DS1阳性的NK细胞对C2/C2组DC的杀伤作用高于其对C1/C1组和C1/C2组DC的杀伤作用,杀伤率分别为（15.06±1.81）％、（10.07±1.03）％和（8.65±0.93）％（F=56.368,P=0.001）.与HLA-C2＋ DC共培养后,KIR2DS1阳性NK细胞表面CCR7阳性表达率增加.结论 活化性的KIR2DS1基因能够在体外有效介导供者NK细胞杀伤受者DC,可能用于预防GVHD;同时能够使NK细胞捕获CCR7,体外获得定向迁移能力.     

KIR2DS1受体对人类NK细胞杀伤白血病细胞的作用研究

目的 探讨活化性杀伤细胞免疫球蛋白样受体（KIR）家族成员KIR2DS1在自然杀伤（NK）细胞杀伤白血病细胞中的作用.方法 采集健康人群外周血单个核细胞,采用NK细胞分选试剂盒富集NK细胞,将分选的NK细胞进行体外扩增培养,以作为效应细胞.取初治确诊的急性髓细胞白血病（AML）患者新鲜骨髓液,分离后的白血病细胞作为靶细胞.采用CCK8比色法检测NK细胞对白血病细胞的杀伤率.采用聚合酶链反应和顺序特异性引物（PCR-SSP）基因分型法分别检测NK细胞及靶细胞的KIR基因和HLA-Cw;根据KIR2DS1表达与否将NK细胞分为KIR2DS1阳性NK细胞与KIR2DS1阴性NK细胞;用抗-KIR2DS1抗体封闭NK细胞的KIR2DS1受体,用CCK8比色法检测封闭前后KIR2DS1阳性组NK细胞对靶细胞的杀伤率.根据HLA-Cw将NK细胞和靶细胞分别分为C1纯合子组（表达HLA-Cw 01、03、07、08、12、14、16）、C2纯合子组（表达HLA-Cw02、04、05、06、15、17、18）和C1/C2杂合子组（既表达C1组的等位基因又表达C2组的等位基因）.结果 经过富集后NK细胞的纯度为（91.2±5.94）％;不同效靶比下,KIR2DS1阳性NK细胞的杀伤率明显高于阴性组;当效靶比为10：1时,KIR2DS1阳性NK细胞组对白血病细胞的杀伤率（42.82±6.81）％高于KIR2DS1阴性组（28.61±5.14）％;抗-KIR2DS1封闭后NK细胞对白血病细胞杀伤作用明显减弱（t=-3.00,P＜0.05）;KIR2DS1阳性NK细胞C1纯合子组对靶细胞C2纯合子组的杀伤率（54.39±3.46）％明显高于靶细胞C1组（41.22±3.68）％（t=8.33,P＜0.05）和C1/C2组（41.32±5.09）％（t=6.37,P＜ 0.05）.结论 KIR2DS1阳性NK细胞对白血病细胞的杀伤效力高于KIR2DS1阴性NK细胞,即KIR2DS1可以有效介导NK细胞杀伤白血病细胞;HLA-C1纯合子的KIR2DS1阳性NK细胞对HLA-C2纯合子的靶细胞杀伤作用强.     

NK细胞抗肿瘤免疫效应机制研究进展

自然杀伤(NK)细胞无需抗原预先致敏即可直接杀伤靶细胞,通常被视为机体免疫防御系统的第一道防线.NK细胞主要通过诱导靶细胞凋亡、释放效应细胞因子、介导抗体依赖性细胞毒性(ADCC)作用等途径杀伤肿瘤细胞.现综述近年来NK细胞在以上效应机制方面的研究进展.     

树突状细胞和自然杀伤细胞与肿瘤细胞端粒酶的研究进展

树突状细胞(DC)将人端粒酶逆转录酶(hTERT)提呈给T淋巴细胞,可激发特异性的细胞毒性T细胞和CD4+T细胞反应.自然杀伤(NK)细胞与肿瘤细胞端粒酶的相关研究较少,而DC和NK细胞共同作用可以增加抗肿瘤活性,有可能与端粒酶共同参与抗肿瘤免疫反应.     

NK细胞抗肿瘤免疫效应机制研究进展

自然杀伤(NK)细胞无需抗原预先致敏即可直接杀伤靶细胞，通常被视为机体免疫防御系统的第一道防线。NK细胞主要通过诱导靶细胞凋亡、释放效应细胞冈子、介导抗体依赖性细胞毒性(ADCC)作用等途径杀伤肿瘤细胞。现综述近年来NK细胞在以上效应机制方面的研究进展。     

急性淋巴细胞白血病患者外周血中KIR2DL4的表达及其对NK细胞杀伤功能的影响

目的:探究杀伤细胞免疫球蛋白样受体2DL4(killer cell Ig-like receptor 2DL4,KIR2DL4)在急性淋巴细胞白血病(acute lymphoblastic leukemia, ALL)患者外周血中的表达,及其对自然杀伤细胞(nature killer, NK)杀伤功能的影响。方法:从ALL患者及健康志愿者的外周血中分离出单个核细胞,采用实时荧光定量PCR检测单个核细胞中KIR2DL4的表达差异;从单个核细胞中分选NK细胞,通过流式细胞仪检测CD3^-CD56⁺标记的NK细胞比例,并分析NK细胞表面KIR2DL4与Molt-4细胞表面人白细胞抗原G(human leukocyte antigen G,HLA-G)的表达水平。分别以NK细胞、KIR2DL4阻断抗体作用的NK细胞、IgG1抗体作用的NK细胞作效应细胞,Molt-4细胞为靶细胞,在不同效靶比(5:1、10:1、20:1)下,利用ELISA检测细胞上清液中干扰素(interferon-gamma,IFN-γ)与肿瘤坏死因子-α(tumor necrosi...     

食管鳞癌患者手术前后外周血T细胞亚群与NK、NKT细胞检测的临床意义

目的:分析食管鳞癌患者手术前后外周血中T淋巴细胞亚群与NK、NKT细胞变化规律及其临床意义.方法:应用流式细胞术检测78例食管鳞癌患者外周血中T淋巴细胞亚群及NK、NKT细胞的水平.结果:肿瘤切除术前NKT细胞水平在中低分化组较高分化组显著下降(P<0.05);术后外周血中CD8+T细胞含量明显降低(P<0.01),CIM+/CD8+比值显著升高(P<0.01),同时NK与NKT细胞水平较术前显著下降(P<0.01).结论:手术可一定程度改善患者机体免疫功能,检查手术前后外周血T淋巴细胞亚群及NK、NKT细胞水平有助于患者的细胞免疫功能监测,为食管鳞癌临床治疗提供依据.     

负载人结肠癌Lovo细胞总RNA抗原树突状细胞对细胞因子诱导的杀伤细胞在体外特异性杀伤的影响

目的 探讨人结肠癌Lovo细胞总RNA抗原致敏的树突状细胞(DC)对细胞因子诱导的杀伤细胞(CIK)在体外特异性杀伤的影响.方法 利用Ficoll密度梯度离心法提取脐血单核细胞,分别诱导CIK和DC细胞,并用流式细胞仪检测其免疫表型.采用Trizol提取结肠癌Lovo细胞总RNA作为肿瘤细胞抗原,转染脐血来源的DC.实验分为3组:转染Lovo DC共培养CIK组、未转染DC共培养CIK组和单纯CIK组.靶细胞为Lovo细胞,在效靶比为50∶1和20∶1的条件下以噻唑蓝法分别检测CIK的体外杀伤活性.结果 在效靶比为20∶1时,负载Lovo RNA抗原的DC能诱导出CIK对Lovo细胞最强的细胞毒杀伤力为(76.49±4.21)%,DC+CIK组次之为(53.84±2.15)%,CIK组细胞毒性最低为(32.20±3.07)%,且两组间差异有统计学意义(P＜0.05).结论 肿瘤细胞总RNA提取方法简单,易于临床实施,其作为抗原致敏DC能强化CIK的特异性杀伤,将有很好的临床应用前景.     

树突状细胞与自然杀伤细胞相互作用研究进展

最近树突状细胞(DC)和自然杀伤(NK)细胞的相互作用引起各国研究人员的注意.体内、体外试验均证实两种细胞相互作用产生细胞毒效应,并能激活、促进DC成熟和NK细胞增殖,这些相互作用的效应在免疫反应中起重要作用.现综述NK-DC相互作用机制及意义的研究进展.     

加热处理后人黑色素瘤A375细胞对NK和DC细胞免疫活性的影响

目的： 研究经加热处理的人黑色素瘤细胞A375对外周血单个核细胞来源的自然杀伤(NK)细胞及树突状细胞(DC)免疫活性的影响并探讨其作用机制。方法：体外培养人外周血单个核细胞来源的NK和DC细胞,并使其与43 ℃水浴加热后的A375细胞共孵育24 h。应用CCK-8法测定加热和非加热组效靶比(NK∶DC∶A375)分别为1∶2∶1、3∶6∶1、6∶12∶1时NK/DC细胞的杀伤率;应用酶联免疫吸附法(ELISA)检测上述各效靶比组NK细胞培养液中γ-干扰素(γ-INF)的释放情况。结果：在每个效靶比,与非加热组比较,加热组NK/DC的杀伤率均明显提高(P<0.05),且其杀伤率随NK/DC细胞的浓度升高而升高(P<0.05)。在加热组和非加热组,含有DC较不含DC组杀伤率均明显提高(P<0.05)。加热组NK细胞γ-INF释放均较非加热组明显增加(P<0.05)。结论：经加热处理后的黑色素瘤细胞A375能够刺激NK细胞分泌更多的γ-INF,明显提高NK细胞的杀伤活性,且DC在其中起着重要作用。     

负载肺癌干细胞膜微粒的 DC －CIK 对耐药肺癌细胞的靶向杀伤作用及对肺癌干细胞凋亡的影响

目的：探讨负载肺癌干细胞膜微粒的 DC －CIK 细胞对 EGFR －TKI 耐药肺癌细胞的杀伤作用及对肺癌干细胞凋亡的影响机制。方法：无血清悬浮细胞培养法富集 EGFR －TKI 耐药肺癌细胞 A549、H292干细胞样细胞,RT －PCR 检测干细胞标志物,裸鼠成瘤实验鉴定致瘤性。超滤和差速离心法获取肺癌干细胞膜微粒。流式细胞术分别测定共孵育组和常规培养组 DC 成熟标志 CD86和 CD83,测定两组 DC －CIK 细胞表型CD3＋、CD3＋CD8＋、CD3＋CD56＋、CD3＋CD4＋;形态观察及 MTT 法分别测定不同效靶比两组 DC －CIK 对A549、H292的杀伤效应;ELISA 法分别检测两组 DC －CIK 上清中 IL －2、IFN －γ、TNF －α分泌水平;流式细胞术分别测定两组 DC －CIK 对肺癌干细胞凋亡的影响。结果：富集培养获得的 EGFR －TKI 耐药肺癌干细胞样细胞高表达干细胞标志物 Sox2和 Oct4,并具较强裸鼠致瘤性。负载膜微粒的 DC 成熟标志 CD86和 CD83较常规 DC 表达显著升高;负载膜微粒的 DC －CIK 较常规 DC －CIK 细胞表型 CD3＋、CD3＋CD8＋、CD3＋CD56＋、CD3＋CD4＋升高,对 EGFR －TKI 耐药肺癌细胞杀伤效应高于常规 DC －CIK,并具有显著提高的靶向趋向性;负载膜微粒的 DC －CIK 分泌因子对 EGFR －TKI 耐药肺癌干细胞样细胞凋亡的影响与常规 DC －CIK 不同。结论：与常规培养 DC －CIK 相比,负载膜微粒的 DC －CIK 活性提高,对 EGFR －TKI 耐药肺癌细胞的体外特异靶向杀伤效应显著提高。细胞分泌因子可显著上调耐药肺癌干细胞的细胞凋亡率。     

TRAIL-mediated killing of acute lymphoblastic leukemia by plasmacytoid dendritic cell-activated natural killer cells

Acute lymphoblastic leukemia (ALL) still frequently recurs after hematopoietic stem cell transplantation (HSCT), underscoring the need to improve the graft-versus-leukemia (GvL) effect. Natural killer (NK) cells reconstitute in the first months following HSCT when leukemia burden is at its lowest, but ALL cells have been shown to be resistant to NK cell-mediated killing. We show here that this resistance is overcome by NK cell stimulation with TLR-9-activated plasmacytoid dendritic cells (pDCs). NK cell priming with activated pDCs resulted in TRAIL and CD69 up-regulation on NK cells and IFN-γ production. NK cell activation was dependent on IFN-α produced by pDCs, but was not reproduced by IFN-α alone. ALL killing was further enhanced by inhibition of KIR engagement. We showed that ALL lysis was mainly mediated by TRAIL engagement, while the release of cytolytic granules was involved when ALL expressed NK cell activating receptor ligands. Finally, adoptive transfers of activated-pDCs in ALL-bearing humanized mice delayed the leukemia onset and cure 30% of mice. Our data therefore demonstrate that TLR-9 activated pDCs are a powerful tool to overcome ALL resistance to NK cell-mediated killing and to reinforce the GvL effect of HSCT. These results open new therapeutic avenues to prevent relapse in children with ALL.     

不同信号肽对嵌合抗原受体T细胞杀伤作用的影响研究

背景与目的:信号肽(signal peptide,SP)是一段存在于前体蛋白N-端的短肽链,能够调节前体蛋白的折叠和转移,在蛋白质的分泌过程中扮演着极其重要的角色.近年来,靶向CD19的嵌合抗原受体(chimeric antigen receptor,CAR)T细胞在白血病治疗中取得了重大突破,关于CAR结构的胞内域改...     

荷CEA-rV的DC增强CD3AK对CEA阳性肿瘤特异性杀伤作用的研究

Objective： To survey the special killing activity of CD3AK on anti-CEA-positive tumor enhanced by umbilical cord blood dendritic cell （DC） loaded with CEA recombinant vaccinia virus （CEA-rV）. Methods： Freshly isolated umbilical blood mononuclear calls （UBMC） were cultivated for 3 h. Suspension cells and attached calls were used to induce CD3AK calls and DC separately. DC was loaded with CEA-rV on the 3rd day to prepare CEA-rV＋DC. CD3AK cells were co-cultured with CEA- rV＋DC on the 8th day, to prepare CEA-rV＋DC＋CD3AK. The killing activity of each effector＇s cell, which included UBMC, CD3AK, DC＋CD3AK and CEA-rV＋DC＋CD3AK, was measured respectively by MTT reduction assay. Results： （1） 4 target cells were con- firmed by CEA monoclonal antibody of rabbit anti-human. Lovo and A549 were really CEA positive cell lines, while Bel-7402 and K562 were CEA negative cell lines. （2） It was showed by flow-cytometry that the mature DC cultured at 10th day expressed MHC I, II molecules such as CD86, CDS0, CD83 and CD40 highly, but CD123 lowly. The expression rates of CD86, CDS0, CD83 and CD40 was 82.7%, 51.1%, 57.5% and 69.4%, respectively. The appearances and intra-cellular structures of DC were observed through light and electron microscope. The diameter of mature DC was 15-20 μm presented the irregular morphologic appearanca, much prominences and pseudopodium. There were abundant mitochondria and endoplasmic reticulum in DC endochylema. （3） The rates of CD3, CD4, CD8 and CD28 in CD3AK cells group were 2 folds higher than that in UBMC group by FACS. It was said that the numbers of the mature T lymphocyte in CD3AK cells group were much greater than that in UBMC group. （4） The killing activities to 4 target cells of 3 effector＇s cells, which included CEA-rV＋DC＋CD3AK, DC＋CD3AK and CD3AK, were much greater than that of UBMC （P〈0.01）. Moreover, comparing with the killing activities of 4 effector＇s： CEA-rV＋DC＋CD3AK group 〉 DC＋CD3AK group 〉 CD3AK group 〉 UBMC group. It showed that, cytokine, DC and CEA-rV could efficiently elevate the killing activity of UBMC on broad-spectrum tumor cells. （5） Comparing with the killing activities of CEA-rV＋DC＋CD3AK and CD3AK cells to CEA positive and negative cells, the killing activities of CEA-rV＋DC＋CD3AK to CEA positive tumor calls, Lovo and A549 calls （P〈0.01） were remarkably better than that to CEA negative tumor cells BEL-7402 and K562 cells （P〈0.05）. It was said that the CEA-rV＋DC could obviously enhance the killing activity of CD3AK on CEA positive tumor cells. Comparing with the killing activities of CEA-rV＋DC＋CD3AK and DC＋CD3AK cells, the killing activity of CD3AK on CEA negative tumor cells was no statistical difference （P〉0.05）. However, the killing activity to CEA positive cells of CEA-rV＋DC＋CD3AK group was notably higher than that of DC＋CD3AK group. Namely, CEA-rV could distinctly promote the special killing activity to CEA positive tumor cells of CD3AK, but could not do it to CEA negative tumor cells. Conclusion： CEA-rV＋DC could obviously enhance the special killing activity of CD3AK on CEA positive tumor cell lines, while the DC only couldn＇t. The results indicated that the CEA-rV played an important role during the special killing activity of CD3AK cells to CEA positive tumor cells.     

自然杀伤细胞对多发性骨髓瘤细胞株KM-3影响的研究

 目的　研究自然杀伤（NK）细胞对多发性骨髓瘤细胞株KM-3杀伤及诱导凋亡的作用。方法　WST-1法观察不同效靶比的NK细胞对KM-3细胞的杀伤作用;流式细胞术检测Annexin-V+／PI-凋亡细胞、线粒体跨膜电位。结果　NK细胞作用于KM-3细胞后,能显著杀伤KM-3细胞,呈剂量和时间依赖性（P＜0.05）;NK细胞作用于KM-3细胞48 h后,Annexin-V+／PI－细胞比例明显增加,呈剂量依赖性（P＜0.05）;NK细胞作用于KM-3细胞效靶比为10∶1时,Annexin-V+／PI－细胞比例明显增加,呈时间依赖性（P＜0.05）;NK细胞作用于KM-3细胞后,KM-3细胞线粒体跨膜电位明显降低,呈剂量和时间依赖性（P＜0.05）。结论　NK细胞能明显杀伤KM-3细胞并诱导其凋亡,均呈剂量和时间依赖性。     

反应性氮代谢产物对NK细胞抗K562细胞活性的影响

目的 探讨外源性、内源性反应性氮代谢产物(RNM)及其清除剂硫普罗宁(TIP)、还原型谷胱甘肽(GSH)、二氢氯组胺(DHT)对NK细胞抗K562细胞活性的影响.方法 体外合成外源性ONOO-,在NK+K562细胞培养体系中,观察外源性ONOO-及其清除剂对K562细胞抑制率(KIR)、肿瘤坏死因子β(TNF-β)和干扰素γ(IFN-γ)的含量及NK细胞活性影响.以白细胞介素2(IL-2)+植物血凝素(PHA)激活单核细胞(MO)呼吸爆发产生内源性RNM,在MO+NK+K562细胞培养体系中,观察内源性RNM对NK细胞活性的影响,然后加入RNM清除剂观察RNM和NK细胞活性的变化.结果 在NK和K562细胞培养体系中加入外源性ONOO-后,NK活细胞率从(93.17±2.57)%下降到(71.87±1.02)%(P＜0.01),KIR从(67.47±2.64)%下降到(43.44±2.87)%(P＜0.01);加入TIP、GSH和DHT后,NK活细胞率分别升高至(91.13±3.67)%(P＜0.05)、(88.03±1.46)%(P＜0.05)和(73.60±2.76)%(P＞0.05),KIR上升至(61.58±1.89)%(P＜0.05)、(60.68±2.07)%(P＜0.05)和(45.26±3.31)%(P＞0.05).以IL-2+PHA+NK+K562为对照,在NK+K562+MO混合培养体系中加入IL-2+PHA,RNM含量从(82.10±6.60)μmom/L增至(193.65±5.95)μmom/L(P＜0.01),KIR从(90.64±3.06)%下降至(61.29±2.22)%(P＜0.01);加入TIP、GSH和DHT后,RNM含量分别降低至(91.32±6.81)μmom/L(P＜0.05)、(84.66±5.99)μmom/L(P＜0.05)和(188.92±5.00)μmom/L(P＞0.05),KIR上升至(84.31±4.56)%(P＜0.05)、(81.65±3.09)%(P＜0.05)和(72.20±4.10)%(P＜0.05).结论 外源性ONOO-和MO呼吸爆发产生的RNM均可使NK细胞的抗K562细胞活性下降.TIP和GSH可通过清除RNM保护NK细胞,提高NK细胞抗K562细胞活性.     

Antibody‐dependent cellular cytotoxicity toward neuroblastoma enhanced by activated invariant natural killer T cells

Anti‐ganglioside GD2 antibodies mainly work through antibody‐dependent cellular cytotoxicity (ADCC) and have demonstrated clinical benefit for children with neuroblastoma. However, high‐risk neuroblastoma still has a high recurrence rate. For further improvement in patient outcomes, ways to maximize the cytotoxic effects of anti‐GD2 therapies with minimal toxicity are required. Activated invariant natural killer T (iNKT) cells enhance both innate and type I acquired anti‐tumor immunity by producing several kinds of cytokines. In this report, we investigated the feasibility of combination therapy using iNKT cells and an anti‐GD2 antibody. Although some of the expanded iNKT cells expressed natural killer (NK) cell markers, including FcγR, iNKT cells were not directly associated with ADCC. When co‐cultured with activated iNKT cells, granzyme A, granzyme B and interferon gamma (IFNγ) production from NK cells were upregulated, and the cytotoxicity of NK cells treated with anti‐GD2 antibodies was increased. Not only cytokines produced by activated iNKT cells, but also NK‐NKT cell contact or NK cell‐dendritic cell contact contributed to the increase in NK cell cytotoxicity and further IFNγ production by iNKT cells and NK cells. In conclusion, iNKT cell‐based immunotherapy could be an appropriate candidate for anti‐GD2 antibody therapy for neuroblastoma.