The impact of stressful life events on natural killer cells

A study was carried out among members of a kibbutz to determine to what extent their capacity to cope with stressors affected natural killer (NK) cells and how this capacity was regulated by personal, family and social resources. The NK activity and NK cell markers were analysed among 92 kibbutz residents. A number of psychosocial parameters (including family function, social support, and demoralization) were assessed in parallel. A significant correlation was found between the capacity of individuals to cope with daily life stress and their cytotoxic NK activity. Individuals who were diagnosed as having anxiety neurosis had a significantly weaker NK activity and their population of Leu-11 positive cells was significantly lower than among those without such symptoms. No significant association could be determined between either NK cell activity or proportion of Leu-11 positive lymphocytes and any of the psychosocial parameters tested. Thus, while coping with stress has a significant effect on the NK system, further studies are required to elucidate the psychosocial mechanisms involved.     

Characterization,quantification, and localization of passenger T lymphocytes and NK cells in human liver before transplantation

Quantification and localization of the main lymphocyte populations were studied in the livers of normal (n=8) and brain dead (n=8) subjects. Cytometric analysis performed on mononuclear cell suspensions obtained from liver biopsies was compared to an automatic image analysis of immunostained sections. The overall number of liver associated lymphocytes was in the usual range of peripheral blood content (2 to 9 · 10⁹ cells). Phenotypic analysis showed predominant NK and CD8+ cells that highly expressed class II antigen and CD25 and CD69 activation markers. Quantitative mapping of these activated lymphocytes revealed their preferential localization in the portal tract and the perisinusoidal area as compared to the pericentrolobular zone, especially in donor livers. This strategic localization could suggest a possible early cooperation between donor lymphocytes and initial infiltrating cells from the recipient and could explain the special immunological status of allografted livers.     

羟基荧光素二醋酸盐琥珀酰亚胺脂标记大鼠肝脏NK细胞体内转输示踪

目的 利用羟基荧光素二醋酸盐琥珀酰亚胺脂(CFSE)标记大鼠肝脏NK细胞进行体内示踪,观察其在受鼠体内的存活.方法 经SD大鼠门静脉转输1×106个/ml CFSE体外标记新鲜分离的SD供鼠肝脏NK细胞,于输人后1、3、7、15 d分别切取肝脏和脾脏行冰冻切片免疫荧光观察,并收集门静脉血监测淋巴细胞和中性粒细胞的比例变化.结果 CFSE对大鼠肝脏NK细胞的标记率为98.63%;转输NK细胞后第1天受鼠肝脏内CFSE荧光最强,7 d时荧光变微弱,15 d时荧光基本消失;脾脏在第1、3天时可见较弱荧光,7 d时荧光消失.转输NK细胞后相同时间点肝脏内CFSE荧光均明显强于脾脏.转输肝脏NK细胞的受鼠门静脉血中性粒细胞比例第1天时最高,随时间延长逐渐下降,第15天时基本回复正常水平,淋巴细胞比例仅一过性降低.结论 转输的肝脏NK细胞在受体内的数量随时间延长而减少,在受体内的存活时间约为15 d.     

NK cells promote peritoneal xenograft rejection through an IFN-gamma-dependent mechanism

BACKGROUND: Natural killer (NK) cells have emerged as major players in anti-viral and anti-tumour immune responses. Like cytotoxic T lymphocytes (CTL), they express perforin and are potent secretors of gamma-interferon (IFN-gamma). However, there is conflicting evidence about their role in mediating rejection of xenogeneic tissue. METHODS: A pig-to-mouse peritoneal cell model of xenotransplantation was used to investigate the effect of NK deficiency on xenograft recovery and the possible mechanisms behind this NK-mediated graft rejection. gamma c(-/-)RAG(-/-) mice were used as a model of NK deficiency. Additionally, NK cells were depleted in RAG(-/-) mice using anti-asialo GM1. The contributions of IFN-gamma, perforin and NKT cells were studied using knock-out mice that were depleted in vivo of T cells. Mice were injected with 10(7) pig cells intraperitoneally and peritoneal fluid was assessed 5 days later for xenograft recovery and phenotypic analysis. The requirement for NK cells for xenograft rejection was also assessed using luciferase-transfected porcine cells in a renal subcapsular model of transplantation. RESULTS: Pig cell recovery was enhanced in both gamma c(-/-)RAG(-/-) and NK-depleted RAG(-/-) mice when compared with RAG(-/-) control mice. IFN-gamma(-/-) mice depleted of T cells also demonstrated superior graft survival compared with their B6 counterparts. However, there were minimal graft survival differences between Pfp(-/-) and B6 control mice. Similarly, a deficiency in NKT cells did not improve pig xenograft recovery from the peritoneum of these mice. CONCLUSIONS: Therefore, we conclude that NK cells, but not NKT cells, are important mediators of xenograft rejection in the peritoneal cavity, and that their role may be unmasked in the absence of T cells. The mechanism for this xenorejection appears to involve IFN-gamma but is perforin independent.     

肝癌、肝硬化中自然杀伤细胞的免疫组织化学研究

目的: 研究原发性肝细胞癌、肝硬化、正常肝组织中自然杀伤(nature killer,NK)细胞数量、分布及其与患者预后的关系.方法: 原发性肝细胞癌60例,单纯性肝硬化62例,正常肝组织23例,以SP免疫组化法检测NK细胞.结果: ①癌中与癌旁组织的NK细胞计数明显高于肝硬化(P<0.01),癌中NK细胞计数高于正常肝组织(P<0.05).②肝癌组织学分级与NK细胞数量无明显关系.③癌中NK细胞随着临床分期的发展有下降的趋势(P<0.05).④15月内转移复发组癌中和癌旁的NK细胞计数均明显低于无转移复发组(P<0.01).结论: NK细胞计数可能是反映机体抗肿瘤免疫状态和判断患者预后的重要指标.     

Negligible role for NK cells and macrophages in delayed xenograft rejection

Abstract Hyperacute rejection (HAR) of a discordant xenograft can be avoided by complement manipulation, but delayed xenograft rejection (DXR) still leads to graft loss. It is generally assumed that macrophages and NK cells play key roles in DXR. In the present study the survival times and cellular infiltrate following guinea pig to rat heart transplantation was analyzed in the course of DXR, following aspecific and specific manipulation of macrophages and NK cells. HAR was overcome by a single injection of cobra venom factor 1 day before heart transplantation. To aspecifically reduce the inflammatory response dominating DXR, dexamethasone (DEXA) was given. Treatment with DEXA markedly reduced infiltration by NK cells, macrophages, and granulocytes. It also led to prolonged graft survival times (median survival of 0.4 days, n = 10, P < 0.05). In the second series of experiments the specific roles of NK cells and macrophages in DXR were further assessed. Monoclonal antibody 3.2.3 was used to selectively deplete NK cells. Liposome‐encapsulated dichloromethylene biphosphonate was given to achieve macrophage depletion. Neither of these specific treatments, alone or combined, led to prolonged graft survival. Immunohistology revealed that at day 2 after transplantation no NK cells or macrophages were present in grafts from the combined treatment group. Only a mild infiltration of granulocytes was observed. Collectively, these results strongly suggest that NK cells and macrophages are not likely to be pivotal cell types in DXR.     

Differential role of natural killer group 2D in recognition and cytotoxicity of hepatocyte‐like cells derived from embryonic stem cells and induced pluripotent stem cells

Stem cell–based approaches have the potential to address the organ shortage in transplantation. Whereas both embryonic stem cells and induced pluripotent stem cells have been utilized as cellular sources for differentiation and lineage specification, their relative ability to be recognized by immune effector cells is unclear. We determined the expression of immune recognition molecules on hepatocyte‐like cells (HLC) generated from murine embryonic stem cells and induced pluripotent stem cells, compared to adult hepatocytes, and we evaluated the impact on recognition by natural killer (NK) cells. We report that HLC lack MHC class I expression, and that embryonic stem cell–derived HLC have higher expression of the NK cell activating ligands Rae1, H60, and Mult1 than induced pluripotent stem cell–derived HLC and adult hepatocytes. Moreover, the lack of MHC class I renders embryonic stem cell–derived HLC, and induced pluripotent stem cell–derived HLC, susceptible to killing by syngeneic and allogeneic NK cells. Both embryonic stem cell–derived HLC, and induced pluripotent stem cell–derived HLC, are killed by NK cells at higher levels than adult hepatocytes. Finally, we demonstrate that the NK cell activation receptor, NKG2D, plays a key role in NK cell cytotoxicity of embryonic stem cell–derived HLC, but not induced pluripotent stem cell–derived HLC.     

微囊豚鼠肝细胞培养及其细胞免疫屏障作用的观察

目的 观察海藻酸钠-多聚赖氨酸-海藻酸钠(APA)微囊化肝细胞的生物学功能及对免疫细胞的隔离效应。方法 用胶原酶门腔静脉灌注法分离豚鼠肝细胞,测定微囊化肝细胞及游离肝细胞培养上清白蛋白水平,用自然杀伤细胞(NK)细胞的细胞毒实验来评价微囊的免疫隔离效应。结果 微囊包裹对肝细胞的活率无明显影响,微囊化肝细胞与裸露肝细胞白蛋白分泌水平差异无显著性(P>0.05),NK细胞对K562靶细胞的细胞毒实验表明微囊可有效地保护囊内细胞不受NK细胞的杀伤作用。结论 APA微囊化肝细胞可保持良好的生物活性,APA微囊对细胞免疫具有免疫隔离作用。     

慢性乙型肝炎病毒感染者外周血T细胞亚群及NK细胞的特点及意义

目的探讨慢性乙型肝炎病毒（hepatitis B virus,HBV）感染者外周血T细胞亚群及NK细胞的特点及临床意义。方法采用流式细胞术检测各研究组,包括慢性乙型肝炎（chronic hepatitis B,CHB）组33例、乙型肝炎失代偿期肝硬化（1iver cirrhosis,LC）组20例、慢性乙型重型肝炎（chronic severe hepatitis B,CSH）组17例及健康对照组（Control）20例的外周血T细胞亚群及NK细胞相对计数,并检测肝功能、HBVDNA含量及HBV血清标志物。结果按Control、CHB、LC、CSH顺序,CD3^＋T细胞、CD8^＋T细胞百分比依次升高,而CIM^＋T细胞、CD4^＋／CD8^＋比值及NK细胞百分比依次降低,且CHB、LC、CSH组与Control组及CHB组与CSH组相比,差异均有统计学意义（P〈0．05或P〈0．008）。CHB患者的CD3^＋T细胞与血清总胆红素（total bilirubin,TB）、HBVDNA含量（log_10）呈正相关（P〈0．001;P〈0．001）;CD8^＋T细胞与HBVDNA含量（log_10）呈正相关（P=0．007）,NK细胞与HBVDNA含量（log_10）（P=0．001）呈负相关。CHB组乙型肝炎e抗原（HBeAg）阳性者的CD4^＋T细胞及CD4^＋／CD8^＋比值低于HBeAg阴性者（P=0．018;P〈0．001）,而HBVDNA含量（log_10）和CD8^＋T细胞高于HBeAg阴性者（P=0．012;P=0．019）。结论慢性HBV感染者外周血T细胞亚群及NK细胞相对值紊乱,且与临床类型、病情、血清HBVDNA水平及HBeAg相关。     

The characterization of peritoneal and pleural exudate cells from malignant effusions

The immune function of peripheral blood cells and cells from the pleural and abdominal effusions of patients with advanced cancer was compared to that of peripheral blood cells from controls. The parameters examined included lymphocyte subsets, natural killer (NK) cell activity, and anti-Daudi and lymphokine-activated killer (LAK) cell activity. The percentage of CD4⁺ pleural and peritoneal exudate cells (PEC) was significantly higher than the percentage of peripheral blood mononuclear cells (PBMC) in the patients. The percentage of CD8⁺CD11⁺ PEC and PBMC, being the suppressor T-cells, of the patients was increased compared with controls, while the percentage of CD8⁺CD11^– PEC, being the cytotoxic T-cells, was identical to the PBMC of both patients and controls. The NK activity of PEC was significantly lower than that of PBMC in both patients and controls, and there was no correlation between the NK activity of PBMC and PEC. Although the anti-Daudi activity of PEC was markedly low, LAK cells with high activity could be induced by culture with interleukin-2 for 4 days. These results suggest that the immune function of cells in malignant effusions may be depressed due to a low population of cytotoxic T cells, low NK activity and increased suppressor T cells, while the local administration of interleukin-2 may induce LAK cells. Therefore, effective local immunotherapy for malignant effusions should not only augment effector cells, but also inhibit supprssor cells.     

The augmentation of lymphokine-activated killer cells induced by partial hepatectomy in mice

Spleen cells that are cultured with interleukin 2 for as short a time as 4 days develop the ability to lyse syngeneic natural killer-resistant tumor cells but not to lyse syngeneic lymphoblasts. When mice were subjected to partial hepatectomy (HEP), the spleen cells exhibited not only an augmentation of natural killer activity, but also an augmentation ofin vitro induction of lymphokine activated killer (LAK) cells. Furthermore, the LAK cells exhibited lytic activities against syngeneic lectin-induced lymphoblasts and regenerating liver cells. The sensitivity of regenerating liver cells to lysis by LAK cells was detected as early as one day after HEP, and continued until day 14. Analysis by cell depletion techniques using monoclonal antibodies and complement, as well as discontinuous gradient sedimentation, indicated that the LAK cells activated by HEP were Thy-1⁺, Lyt-2⁺, asialo GM1⁺ and Lyt-1⁻, lymphocytes with a low density. After the intravenous (i.v.) administration of anti-asialo GM1 before HEP, thein vitro induction of LAK cells was remarkably inhibited.     

腰椎间盘突出症与Th细胞、NK细胞的相关性研究

目的:探讨辅助性T细胞17(T help cell 17,Th17)、自然杀伤细胞(natural killer cell,NK)在腰椎间盘突出症发生发展中的作用,以求进一步明确神经根痛的病理机制.方法:选取南通大学附属医院脊柱外科收治接受手术治疗的腰椎间盘突出症患者20例作为观察组(椎间盘突出组),同时选取腰椎骨折需摘除椎问盘的患者6例作为对照组(正常髓核组).运用流式细胞术(Flow Cytometry,FCM),分别测定观察组和对照组患者髓核组织中CD3、CD4、T细胞胞内产物白介素-17(IL-17)及NK细胞表面因子CD16CD56的含量.结果:观察组髓核中的CD4、IL-17和CD16CD56含量分别为(3.18±0.15)％、(2.94±0.04)％、(3.24±1.65)％,有高表达;而对照组髓核中的CD4、IL-17和CD16CD56含量分别为(0.08±0.02)％、0％、(1.73±0.71)％,低表达或者不表达,两组间比较差异有显著性(P值分别为0.000,0.000,0.003).观察组与对照组髓核中CD3的表达分别为(23.42±5.84)％和(26.54±4.17)％,两组间差异无显著性(P＞0.05).结论:髓核作为自身抗原可促使Th细胞分化成以IL-17为主的Th17细胞,并诱导CD 16CD56为表面标志的NK细胞的表达,可能参与了腰椎间盘突出症的发生发展.     

滤泡液中自然杀伤细胞活化与卵胞浆内单精子注射结局的探讨

目的探讨滤泡液中CD56^＋自然杀伤（NK）细胞及活化的CD56^＋NK（CD56^＋CD69^＋NK）细胞的比例与不育患者卵胞浆内单精子注射（ICSI）结局的关系。方法应用流式细胞仪分析成熟滤泡液中CD56^＋NK细胞及活化的CD56^＋NK细胞的比例,与ICSI治疗结果的相关性。结果妊娠患者的滤泡液中平均CD56^＋NK细胞及活化的CD56^＋NK细胞分别为（18．8±2．8）％和（1．6±0．8）％,而未妊娠患者的滤泡液中其分别为（37．4±5．8）％和（4．7±1．9）%,均显著高于妊娠组（P〈0．05）。结论接受ICSI助孕治疗患者的成熟滤泡液中CD56^＋NK细胞及活化的CD56^＋NK细胞的比例较低者易获临床妊娠。     

Xenogeneic human anti-pig cytotoxicity mediated by activated natural killer cells

Abstract: Even if hyperacute rejection, which is mediated by human natural antibodies (nAb) and complement, could be prevented, xenoreactive human anti-pig cellular responses may lead to delayed and/or chronic xenograft rejection. Among the cell populations participating in such rejection, NK cells have been proposed as an important component. In this study we report the in vitro cytotoxic activity of natural killer (NK) cells obtained from healthy human donors against porcine target cells. Freshly isolated peripheral blood mononuclear cells (PBMC) and purified NK cells (CD16+/CD56+, CD3-, CD20-, CD33-) exhibited little or no cytotoxic activity when tested on porcine phytohemagglutinin (PHA)-stimulated lymphoblasts or bone marrow- or aortic-derived endothelial cell lines in the presence of serum-free medium. Killing was considerably higher in the presence of human decomplemented plasma, containing xenoreactive nAb, or purified Gal(α1,3)Gal-reactive antibodies, suggesting that antibody dependent cell-mediated cytotoxicity (ADCC) mediated by NK cells is an important mechanism involved in xenogeneic cytotoxicity. After incubation of human PBMC for 6 days in the presence of irradiated xenogeneic porcine or allogeneic stimulator cells, or in the presence of exogenous interleukin 2 (IL-2), the cytotoxic activity of the bulk cultures as well as that of isolated NK cells (separated from stimulated bulk cultures) against xenogeneic targets increased considerably, and corresponded to an increased NK-specific lysis of K562 target cells. Cell surface staining and flow cytometry showed that CD16+/CD56+, CD3- NK cells composed ca. 25% of short-term (6 days) xenogeneic, allogeneic, or IL-2 stimulated bulk cultures. In summary, these data suggest that, in contrast to allogeneic cell- mediated killing, xenogeneic human anti-porcine cytotoxicity includes an important contribution from NK cells.     

脑梗死后抑郁大鼠脑内NK1受体表达变化的研究

目的：探讨P物质受体NK1与脑梗死后抑郁的关系。方法：健康雌性SD大鼠48只，随机分成4组：抑郁组（MD组）、大脑中动脉皮质支闭塞组（MCAO组）、梗死后抑郁组（PSD组）和正常对照组，模型制做成功后第4周和8周利用敞箱试验评估大鼠抑郁程度，平衡木试验评估大鼠神经功能缺损程度，间接免疫荧光法检测脑内NK1受体的表达。结果：MCAO组和PSD组术后平衡木评分较同期正常对照组和MD组低，4周基本恢复正常。PSD、MD组各时点敞箱垂直活动、水平活动评分较同期MCAO、正常对照组低，8周较4周进一步降低，但PSD和MD组间比较差异无显著意义。PSD和MCAO组大鼠术侧皮质均见梗死灶，未累及基底节区，4周见中风囊形成，8周部分大鼠患侧侧脑室扩张；MD组和正常对照组未见脑梗死灶。梗死后4周，MD组和PSD组NK1表达阳性细胞平均灰度值均较同期MCAO组和正常对照组增高，8周进一步增高（P〈0．05），但两组间差异没有显著性；MCAO组4周较对照组增高，8周基本正常。结论：NK1受体高表达与梗死后抑郁有关，可能参与梗死后抑郁的发生发展过程。     

肝癌、肝硬化组织中CD3、CD57、CD20细胞数量与临床病理表现及预后的关系

目的探讨CD3、CD57、CD20细胞在原发性肝细胞癌(HCC)、癌旁、肝硬化及正常肝组织中的数量及意义.方法HCC 60例,单纯性肝硬化62例,正常肝组织23例,以免疫组化SP法进行CD3、CD57、CD20染色,对阳性细胞数进行定量分析并与临床资料进行相关探讨.结果(1)各组CD3+细胞平均数从高到低为癌旁组织、癌组织、肝硬化组织、正常肝组织(P＜0.05);各组CD57+细胞平均数从高到低为癌组织、癌旁组织、正常肝组织、肝硬化组织(P ＜0.05);各组CD20+细胞平均数从高到低为癌组织、癌旁组织、肝硬化组织、正常肝组织(P ＜0.01).(2)HCC中CD3+细胞、CD57+细胞、CD20+细胞与组织学分级均无明显关系.(3)HCC中CD57+细胞和CD20+细胞随着临床分期的发展有下降的趋势(P ＜0.05);HCC中CD3+细胞平均数与临床TNM分期无关.(4)HCC中15月内有转移组的CD57+、CD3+细胞数均少于无转移组(P＜0.01).HCC患者15月内有无转移与HCC和癌旁组织中的B细胞分布均无关.结论临床上,随着HCC患者的病情恶化,CD3+、CD57+、CD20+细胞逐渐减少.CD3+、CD57+、CD20+细胞可成为反映机体抗肿瘤特异性细胞免疫状态和生物学行为及判断患者预后的重要指标.     

新生猪胰岛细胞的HLA-G1基因转染

目的探讨HLA-G1基因转染新生猪胰岛细胞的可行性,检测其表达和功能状况。方法体外分离纯化新生猪胰岛细胞,脂质体载体转染HLA-G1基因。免疫荧光法检测HLA-G1基因在胰岛细胞上的表达状况;51Cr释放实验分析其对人NK细胞细胞毒的抑制作用。结果新生猪胰岛细胞HLA-G1基因表达率大约为50%,体外转染24-48 h达高峰;混合淋巴细胞培养(胰岛细胞 NK细胞)后,空质粒转染组的胰岛细胞溶解率为71.57%,而转染组胰岛细胞溶解率为53.5%。结论利用脂质体Genejammer转染体外培养的新生猪胰岛细胞,可以获得靶基因的瞬时高效表达; HLA-G1基因转染可以有效抑制NK细胞对异种胰岛的细胞毒作用。     

单核细胞、NK细胞和T细胞在猪-猕猴延迟性异种移植排斥反应中的作用

目的观察单核细胞、NK细胞和T细胞在猪-猕猴延迟性异种移植排斥反应(DXR)中的作用。方法建立湖北白猪-云南猕猴的腹腔异位心脏移植模型，实验分为2组：对照组(n=5)，不使用中华眼睛蛇毒因(Y-CVF)；实验组(n=4)应用Y-CVF完全清除受者体内补体。2组受体猴均采用环孢素A(CsA)，环磷酰胺(CTX)和甲基强的松龙(MP)三联免疫抑制治疗。免疫组织化学方法检测移植心组织中细胞间黏附分子(ICAM)-1、肿瘤坏死因子(TNF)-α、单核细胞、NK细胞和T细胞的表达。结果对照组3个移植心在15～60min内发生超急性排斥反应(HAR)，另2个分别存活22h及6d，移植心均未见明显的炎性细胞浸润及ICAM-1和TNF-α的表达。实验组移植心存活时间分别为8、10、13和13d，移植物浸润细胞中可见大量的单核细胞(50％)，少量的NK细胞(8％～10％)，CD4^ T细胞(15％)和C08^ T细胞(25％)。移植物血管内皮细胞表面出现ICAM-1的表达上调，移植物间质中出现TNF-α的表达增加。结论单核细胞、NK细胞和T细胞介导的移植物损伤，在应用Y-CVF处理的猪-猕猴DXR发生中发挥重要作用。     

The regulation of natural killer cell activity by splenic nonspecific suppressor cells and its modification in cancer patients

Spleen cells (SC), splenic venous blood lymphocytes (SVL) and peripheral blood lymphocytes (PBL) from gastric and esophageal cancer patients were simultaneously tested for natural killer (NK) and nonspecific suppressor (Ts) cell activities. Furthermore, the influence of Ts activity on the augmentation of NK activity by a biological response modifier (BRM) was also investigated. Positive Ts activities were frequently detected in the SC, SVL and PBL of advanced cancer patients. The NK activities of SC and SVL were maintained even in advanced cancer patients, though significantly depressed NK activities were observed in the PBL of advanced cases. Cancer patient SC, SVL and PBL with positive Ts activity showed low NK activities. Moreover, the NK activities of SVL and PBL were low in the patients with positive Ts activity in SC. The NK activity of normal control PBL was strongly augmented by interleukin 2, interferon and OK-432. These BRMs exhibited comparable capacities to augment the NK activities of SC, SVL and PBL with negative Ts activity in cancer patients, however, the effects of these agents seemed to be low in cells with a positive Ts activity. These results suggested that NK activity might be regulated by nonspecific suppressor cells and the presence of suppressor cells might affect the augmentation of NK activity through BRM in circulating blood lymphocytes and also in spleen cells.