Research on stress-induced apoptosis of natural killer cells and the alteration of their killing activity in mouse liver

AIM:To investigate the stress-induced apoptosis of natural killer(NK)cells and the changes in their killing activity in mouse livers.METHODS:A restraint stress model was established in mice.Flow cytometry was employed to measure the percentage of NK cells and the changes in their absolute number in mouse liver.The cytotoxicity of hepatic and splenic NK cells was assessed against YAC-1 target cells via a 4 h 51Cr-release assay.RESULTS:The restraint stress stimulation induced the apoptosis of NK cells in the liver and the spleen,which decreased the cell number.The number and percentage of NK cells in the spleen decreased.However,the number of NK cells in the liver decreased,whereas the percentage of NK cells was significantly increased.The apoptosis of NK cells increased gradually with prolonged stress time,and the macrophage-1(Mac-1)+NK cells were more susceptible to apoptosis than Mac-1-NK cells.Large numbers of Mac-1-NK cells in the liver,which are more resistant to stress-induced apoptosis,were observed than the Mac-1-NK cells in the spleen.The stress stimulation diminished the killing activity of NK cells in the spleen was significantly decreased,but the retention of numerous Mac-1-NK cells in the liver maintained the killing ability.CONCLUSION:Significant stress-induced apoptosis was observed among Mac-1+NK cells,but not Mac-1-NK cells in the mouse liver.Stress stimulation markedly decreased the killing activity of NK cells in the spleen but remained unchanged in the liver.

Autologous Natural Killer Cell/Natural Killer T Cell Immunotherapy of Malignant Diseases

Adoptive immunotherapy, the therapeutic infusion of ex vivo activated cancer-fighting white blood cells that was pioneered by Dr. Steven Rosenberg over 30 years ago, has become more widespread due to outstanding published research documenting the clinical efficacy of this strategy. Based on the well-established in vivo functions of NK and NKT cells, their integral role in the efficacy of certain chemotherapeutic and immunomodulatory agents, and their direct therapeutic action as displayed in clinical trials, the use of autologous natural killer cell infusions is an appropriate and warranted therapeutic option for the treatment of malignant diseases, especially in patients whose disease is refractory to standard treatments such as chemotherapy and radiation.

Clinical Detection of Peripheral Blood Natural Killer Cell Activity

Natural Killer (NK) cells are specific immune cells in human immune system. They have a quick effect and can exert a cytotoxic function without prior sensitization, and they show great application potential in cell-based immunotherapy, anti-infection in vivo. NK cell activity in peripheral blood can be used as one of the biomarkers of immune function response. It has a great positive guiding significance for the clinical prognosis of tumor patients, the prevention of cancer and anti-aging. The clinical detection strategies of NK cell activity in circulation mainly grouped into five types: methyl thiazolyl tetrazolium colorimetric, lactate dehydrogenase release, radionuclide labeling, flow cytometry and NK Vue cytokine release method. It has played an important role in different stages of clinical application development. This paper will make a comparative review of the above-mentioned detection strategies for the NK cell activity.

The Cell Biology of Systemic Hyperinflammation Resulting from Failed Cytolytic Target Cell Killing

Mutations in genes encoding a key component of cytotoxic granules, or the machinery for their release, underlie the systemic hyperiflammatory symptoms of familial hemophagocytic lymphohistiocytosis (FHL), a typically pediatric onset autosomal recessive disorder with five known genetic subtypes (FHL1 - 5). FHL1 mutations have been mapped to chromosome 9, while the respective genes mutated in FHL2 (PRF1), FHL3 (UNC13D/Munc13-4), FHL4 (STX11) and FHL5 (STXBP2/ Munc18b/Munc18-2) have been identified. Perforin gene mutation directly affected the cytolytic activity of the cytotoxic granules. All the other FHL mutations appear to affect some aspect of cytotoxic granule exocytosis, resulting in impaired target cell killing by cytolytic T lymphocytes (CTLs) and/or natural killer (NK) cells. Recent findings suggest that failure to kill and detach from target cells, and prolonged synapse connection time, promote cytokine hypersecretion by the defective CTLs and NKs, which in turn result in systemic inflammation. Deciphering the genetics of FHL has contributed towards our understanding of the cell biology of hyperinflammatory responses and hemophagocytic lymphohistiocytosis accompanying pathological conditions such as cancer and viral infections.

自然杀伤(NK)细胞与2019冠状病毒病(COVID-19)发生发展的研究进展

自然杀伤(NK)细胞在清除病毒,执行免疫调节方面发挥着重要的作用,它通过分泌趋化因子以及与其他天然免疫细胞协同作用,被赋予天然免疫调节功能和获得性免疫反应。随着对严重急性呼吸综合征冠状病毒2(SARS-CoV-2)感染的2019冠状病毒病(COVID-19)的研究深入,发现NK细胞在其中发挥着重要作用。SARS-CoV-2感染会影响NK细胞的分布和效应功能,NK细胞的免疫应答或可影响新冠肺炎患者的预后。本文总结了近年来NK细胞在COVID-19感染中作用的研究现状,并且讨论了以NK细胞作为治疗剂的可能性,以期为防治SARS-CoV-2的免疫损害提供潜在思路。

基于自然杀伤(NK)细胞的肝癌免疫疗法研究进展

肝细胞肝癌(HCC)异质性高,晚期诊断和化疗耐药使其成为我国难治性肿瘤之一。自然杀伤(NK)细胞在机体的免疫监视过程中充当重要角色。但在肝癌的进展过程中,NK细胞的功能受损致肿瘤免疫逃逸。该文总结了HCC中基于NK细胞的不同免疫治疗策略,包括直接输注过继性NK细胞免疫疗法、基因工程NK细胞免疫疗法、靶向NK细胞受体免疫疗法、改变免疫抑制微环境免疫疗法、细胞因子增强NK细胞肿瘤毒性免疫疗法以及中医药增强NK细胞肿瘤毒性免疫疗法,这些基于NK细胞的免疫治疗策略已显示出巨大的治疗潜力。

Case Report: Feasibility and Safety of Autologous NK Cell Therapy in Patients with Cancer

This study reported two cases of Thai cancer patients, including a 36-year-old female with thyroid cancer of more than 5 years and a 64-year-old male with lung and colon cancers of more than 10 years. The written informed consent was provided for autologous natural killer (NK) cell infusion at the anti-ageing and regenerative medicines clinic. Briefly, the blood was taken from the patient for NK cell count and their cytotoxic activity. Then, the patient’s NK cells were expanded in vitro, characterized and then counted before being delivered to the same patient by a single intravenous infusion. The vital signs and general physical examinations were observed for 2 - 6 hours after the infusion. The patients were discharged if there were no adverse effects. The data showed the increasing number of NK cells and level of cytotoxic activity after the NK cell treatment, compared to the pre-treatment. In addition, the increasing total live cell concentration, as identified by the high percentage of CD56dim/CD16bright cytotoxic NK cells, at day 21 of the NK cell expansion was consistent with the increasing cytotoxic activity of the patients after the treatment. Here, we demonstrated that this autologous NK cell therapy might be feasible;however, the study did not aim to evaluate the anti-cancer effect.

The Skin Whitening Effect of Co-Cultured Conditioned Medium: Involvement of Synergy between Stem Cells and Immune Cells

Many researchers have described that mesenchymal stem cells conditioned medium and immune cells conditioned medium have a clear whitening effect when they are used as cosmetic ingredients. In this study, we confirmed the whitening efficacy of various concentrations of immune cells and stem cell conditioned media. The author tried to study a conditioned medium that has a strong whitening effect even with a composition of less than 20% (the most used concentration in cosmetics). Because of the fact that the conditioned medium contains various cytokines and growth factors secreted by stem cells or immune cells, it is known to have effects such as wound healing, antioxidant, and whitening effect. Recently, stem cells have been used not only in the development of cosmetic raw materials but also in skincare procedures, and there are reports being released of cosmetics using immune cells conditioned medium. The concentration-dependent whitening effect equivalently increased as the concentration of the mono-cultured conditioned medium was obtained through the stem cells or immune cells culture. In the case of co-culture, whitening results are like the effect of positive control such as arbutin in the medium carrying only 10% of the co-cultured conditioned medium. It is possible that enhanced whitening efficiency in co-cultured conditioned medium leads to a major innovation in the global cosmetic market.

NKG2A-HLA-E轴介导NK细胞应答在病毒感染性疾病中的作用及机制研究进展

自然杀伤(NK)细胞主要通过迅速释放细胞毒性介质以及细胞因子直接杀伤病毒感染的靶细胞。NK细胞表面抑制性和活化性受体的平衡以及靶细胞上相应配体的表达均参与调控NK细胞的杀伤功能。其中NK细胞2组成员A(NKG2A)是NK细胞上备受关注的抑制性受体之一,通过与其配体人类白细胞抗原E(HLA-E)的相互作用,可抑制NK细胞对自身正常组织细胞的杀伤活性。研究发现病毒感染细胞表面HLA-E表达上调,并且可与病毒蛋白来源的多肽结合形成复合物,通过与NKG2A的相互作用调控NK细胞功能,从而参与病毒感染性疾病发病过程。本文总结了NKG2A与HLA-E分子互作特点,以及NKG2A-HLA-E轴参与调控NK细胞的功能机制,有助于了解NK细胞在病毒感染性疾病中的重要作用。

Avian influenza virus directly infects human natural killer cells and inhibits cell activity

Natural killer （NK） cell is a key component of innate immunity and plays an important role in host defense against virus infection by directly destroying infected cells. Influenza is a respiratory disease transmitted in the early phase of virus infection. Evasion of host innate immunity including NK cells is critical for the virus to expand and establish a successful acute infection. Previously, we showed that human influenza HIN1 virus infects NK cells and induces cell apoptosis, as well as inhibits NK cell activity. In this study, we further demonstrated that avian influenza virus also directly targeted NK cells as an immunoevasion strategy. The avian virus infected human NK cells and induced cell apoptosis. In addition, avian influenza virion and HA protein inhibited NK cell cytotoxicity. This novel strategy has obvious advantages for avian influenza virus, allowing the virus sufficient time to expand and subsequent spread before the onset of the specific immune response. Our findings provide an important clue for the immunopathogenesis of avian influenza, and also suggest that direct targeting NK cells may be a common strategy used by both human and avian influenza viruses to evade NK cell immunity.

慢性HBV感染者外周血T淋巴细胞亚群和NK细胞活性变化

探讨慢性HBV感染者外周血T淋巴细胞亚群及NK细胞活性变化情况。应用流式细胞法检测所有研T淋巴细胞亚群和NK细胞。慢性乙肝、肝炎肝硬化和慢性重型乙肝组患者CD3+、CD4+百分率及CD4+／CD8+比值与正常组比较均有所下降,且慢性重型乙肝组患者CD4+百分率和CD4+／CD8+比值与正常组比较差异有显著性。各临床类型慢性HBV感染者NK细胞百分率均降低,与正常对照组比较有统计学意义。慢性HBV感染者细胞免疫功能低下。检测T淋巴细胞亚群及NK细胞活性变化对判断病变程度、指导临床治疗具有一定参考价值。

糖萜素对小鼠NK细胞活性影响的研究

目的 :探讨糖萜素对机体 NK细胞活性的影响。方法 :1体外试验 ,不同浓度糖萜素体外直接作用小鼠脾细胞和 YAC-1细胞 ,用 MTT法测定细胞生长代谢和 NK细胞活性 ;2体内试验 ,以糖萜素饲料和普通饲料分别喂养正常和免疫抑制 (环磷酰胺抑制 )小鼠 ,在不同时间段检测 NK细胞活性。结果 :1体外 <5μg/ ml的糖萜素浓度 ,对小鼠脾细胞生长和 NK细胞活性无明显影响 ( P>0 .0 5) ;2以糖萜素饲料喂养的正常小鼠和免疫抑制小鼠 ,各时间段 NK细胞活性明显高于喂养普通饲料的对照小鼠 ( P<0 .0 5)。结论 :口服糖萜素能明显增强小鼠 NK细胞活性 ,且使其稳定维持在高水平。

不同肿瘤细胞表面MICA的表达及NK细胞杀伤活性的研究

目的观察不同肿瘤细胞表面MICA的表达及其对NK细胞杀伤活性的影响。方法以体外培养的K562(人慢性髓原白血病细胞株)、MCF-7(乳腺癌细胞株)、HR-8348(直肠腺癌细胞株)、CNE-2(人鼻咽癌细胞株)、Hela(人宫颈癌细胞株)为靶细胞,流式细胞仪检测细胞表面MICA的表达,以K562细胞作为对照,应用LDH释放法检测不同效靶比情况下体外培养的NK细胞对靶细胞的杀伤活性。结果K562、MCF-7、HR-8348、CNE-2、Hela细胞表面均表达MICA,体外杀伤试验表明NK细胞对上述肿瘤细胞均有杀伤活性,anti-MICA单抗可部分封闭NK细胞对靶细胞的杀伤活性。结论NK细胞对K562、MCF-7、HR-8348、CNE-2、Hela细胞具有较高的杀伤活性,可作为一种生物治疗手段。

MICA分子在NK细胞杀伤乳腺癌中的作用

目的观察乳腺肿瘤细胞膜MHCⅠ链相关分子A(MHC class I chain-related gene A,MICA)及血清中可溶性MICA表达,探讨MICA在NK细胞杀伤乳腺癌中的作用。方法流式细胞术检测膜型MICA(mMICA)及NK细胞表面NKG2D表达,观察膜型MICA、可溶性MICA(sMICA)对NKG2D表达的影响;免疫组织化学检测膜型MICA及可溶性MICA的表达及分布;抗体封闭法观察膜型MICA与NKG2D相互作用。结果乳腺细胞膜型MICA在正常组织不表达,在良性肿瘤表达量为(38.5±7.5)%,恶性肿瘤表达量为(53.2±5.6)%。可溶性MICA含量在健康成年人为阴性,在乳腺良性肿瘤患者血清中含量(76.8±22.3)pg/mL,在恶性肿瘤患者中含量(205.36±71.27)pg/mL。经NKG2D或MICA抗体封闭后,NK细胞的杀瘤活性显著减弱。含可溶性MICA的血清可明显下调NKG2D的表达。结论大部分乳腺肿瘤细胞膜都有MICA的表达,可作为乳腺肿瘤相关性抗原。膜型MICA与NKG2D的相互识别在介导NK细胞抗乳腺癌中起重要作用,而可溶性MICA通过下调NKG2D表达介导肿瘤免疫逃逸。

板蓝根多糖促进NKG2D配体表达增强NK细胞对食管癌细胞的杀伤作用及机制研究

目的:研究板蓝根多糖(RIP)影响NK细胞对食管癌细胞杀伤作用的分子机制。方法:MTT法检测细胞增殖率,Western blot检测增殖相关蛋白CyclinD1、p21和p27的表达,ELISA法检测培养上清中IFN-γ和TNF-α的表达,流式细胞术检测NKG2D配体MICA、MICB、ULBP1和ULBP2的表达,钙黄绿素释放法(CARE-LASS)检测NK细胞对食管癌细胞的杀伤率。结果:RIP可促进NK-92细胞增殖,抑制食管癌Eca-109细胞增殖,且具有显著剂量依赖性。食管癌可促进NK细胞中TNF-α和IFN-γ的表达。RIP可促进食管癌细胞Eca-109中NKG2D配体MICA、MICB、ULBP1和ULBP2的表达,促进与食管癌细胞联合作用后NK细胞中TNF-α和IFN-γ表达,提高NK-92细胞对食管癌Eca-109细胞的杀伤活性。结论:RIP通过提高食管癌Eca-109细胞中NKG2D配体表达,促进NK-92细胞中TNF-α和IFN-γ表达,增强NK-92细胞对食管癌细胞的杀伤作用。

帕金森病患者NK细胞亚群及T淋巴细胞亚群变化的临床意义

目的:探讨帕金森病(PD)不同年龄、不同病期、伴随症状患者外周血NK细胞亚群及T淋巴细胞亚群的变化及其临床意义。方法:应用先进的流式细胞仪(FCM)直接免疫荧光染色法检测47例PD患者外周血NK细胞亚群及T淋巴细胞亚群,并与健康人组进行对照与相关分析。结果:PD组CD3+、CD4+、CD8+、CD4+/CD8+水平较对照组均明显降低(P<0.05),而CD16+56水平则较对照组明显增高(P<0.05)。高龄、病情重及伴痴呆和抑郁的PD患者CD3+、CD4+、CD8+、CD4+/CD8+水平降低更显著(P<0.05)。结论:PD发病过程中存在T细胞免疫功能低下及NK细胞免疫平衡失调,高龄、病情重及伴痴呆和抑郁的患者NK、T细胞免疫功能异常降低更明显,此为PD病理生理基础赋予新的内涵,亦为PD的免疫干预性治疗提供新的途径。

重度子痫前期患者血清对外周血NK细胞杀伤活性的影响

目的研究重度子痫前期患者血清对NK细胞杀伤活性影响。方法重度子痫前期患者组(病例组)、正常妊娠妇女组(对照组)各15例,采用1∶1配比的病历对照研究。采用Percoll不连续密度梯度方法分离健康非孕妇女NK细胞,用10%、20%、40%浓度重度子痫前期患者血清及20%正常妊娠妇女血清孵育NK细胞20 h,。采用MTT法检测不同血清对NK细胞杀伤活性影响。结果在用20%重度子痫前期患者血清及正常妊娠血清孵育20 h后,重度子痫前期组NK细胞杀伤活性为(48.68±8.47)%,正常妊娠组为(35.21±8.24)%。与正常妊娠组相比,重度子痫前期组NK细胞杀伤活性增强,差异有统计学意义(P<0.01)。在重度子痫前期组,用10%浓度血清孵育20 h后,NK细胞杀伤活性为(39.98±7.65)%,40%浓度血清组为(58.33±7.45)%,重度子痫前期组中10%、20%、40%浓度血清组间两两相比,差异有统计学意义(F=24.326,P<0.01)。结论子痫前期患者血清中某些因子可使NK细胞杀伤活性增强。

肺气虚证和肺阴虚证患者外周血NK细胞表达分析

目的:观察肺气虚证患者和肺阴虚证患者外周血自然杀伤细胞(NK 细胞)表达状况。方法:应用流式细胞仪分别对58例肺气虚证患者、12例肺阴虚证患者和20例健康查体者 CD_(16)/CD_(56)进行测定。结果:肺气虚证患者和肺阴虚证患者 NK 细胞活性下降;肺气虚证各组间 NK 细胞活性也存在明显的差异。结论:肺气虚证患者免疫功能由早期的活跃状态逐步发展到不同程度的免疫抑制,然后发展至肺阴虚证,最终导致免疫系统内环境稳定失调。

血管内皮细胞(ECV304)表达的HLA-G1对NK细胞杀伤活性的抑制作用

目的:证实HLA-G1分子能够抑制NK细胞对同种血管内皮细胞系的杀伤作用。方法:采用脂质体介导的DNA转染技术,以构建的真核表达质粒pcDNA3-HLA-G1转染人脐静脉内皮细胞系ECV304,再用免疫荧光法检测表达的HLA-G1分子。并用MTT比色法检测HLA-G1对NK细胞杀伤活性的影响。结果:ECV304细胞上可稳定表达HLA-G1。NK细胞对空质粒pcDNA3转染的ECV304细胞的杀伤率为(50.6±18.1)%;而对pcDNA3-HLA-G1转染的ECV304细胞的杀伤率为(29.7±11.4)%,两者差异具有显著意义(P<0.01)。结论:HLA-G1分子可明显抑制NK细胞对同种血管内皮细胞的杀伤效应。

Harnessing natural killer cells to develop next-generation cellular immunotherapy

Cellular immunotherapy harnesses the body’’s own immune system to fight cancer by using engineered T cells,macrophages,or natural killer(NK)cells.Compared to chimeric antigen receptor T(CAR-T)cells that are commonly used to treat hematological malignancies,CAR-NK cells have shown remarkable therapeutic effectiveness while exhibiting enhanced safety,reduced risk of graft-versus-host disease,fewer side effects,and amplified antitumor efficacy.Preclinical trials have unveiled the high potential of adoptive CAR-NK cell therapy to curtail or even eliminate both hematological malignancies and solid tumors in animal models.We brought forth herein the design principle of CAR-NK cells,highlighted the latest progress in the preclinical testing and clinical trials of CAR-NK cells,briefly delved into discussed major roadblocks in CAR-NK therapy,and discussed potential solutions to surmount these challenges.Given the accelerated progress in both basic and translational studies on immune cell engineering,CAR-NK cell therapy promises to become a serious contender and important addition to the next-generation cell-based immunotherapy.