Why natural killer cells in triple negative breast cancer?

The triple-negative subtype of breast cancer(TNBC)has the bleakest prognosis,owing to its lack of either hormone receptor as well as human epidermal growth factor receptor 2.Henceforth,immunotherapy has emerged as the front-runner for TNBC treatment,which avoids potentially damaging chemotherapeutics.However,despite its documented association with aggressive side effects and developed resistance,immune checkpoint blockade continues to dominate the TNBC immunotherapy scene.These immune checkpoint blockade drawbacks necessitate the exploration of other immunotherapeutic methods that would expand options for TNBC patients.One such method is the exploitation and recruitment of natural killer cells,which by harnessing the innate rather than adaptive immune system could potentially circumvent the downsides of immune checkpoint blockade.In this review,the authors will elucidate the advantageousness of natural killer cell-based immuno-oncology in TNBC as well as demonstrate the need to more extensively research such therapies in the future.

Microwave-induced Apoptosis and Cytotoxicity of NK Cells through ERK1/2 Signaling

Objective To investigate microwave-induced morphological and functional injury of natural killer（NK） cells and uncover their mechanisms. Methods NK-92 cells were exposed to 10, 30, and 50 m W/cm^2 microwaves for 5 min. Ultrastructural changes, cellular apoptosis and cell cycle regulation were detected at 1 h and 24 h after exposure. Cytotoxic activity was assayed at 1 h after exposure, while perforin and NKG2 D expression were detected at 1 h, 6 h, and 12 h after exposure. To clarify the mechanisms, phosphorylated ERK（p-ERK） was detected at 1 h after exposure. Moreover, microwave-induced cellular apoptosis and cell cycle regulation were analyzed after blockade of ERK signaling by using U0126. Results Microwave-induced morphological and ultrastructural injury, dose-dependent apoptosis（P 〈 0.001） and cell cycle arrest（P 〈 0.001） were detected at 1 h after microwave exposure. Moreover, significant apoptosis was still detected at 24 h after 50 m W/cm^2 microwave exposure（P 〈 0.01）. In the 30 m W/cm^2 microwave exposure model, microwaves impaired the cytotoxic activity of NK-92 cells at 1 h and down regulated perforin protein both at 1 h and 6 h after exposure（P 〈 0.05）. Furthermore, p-ERK was down regulated at 1 h after exposure（P 〈 0.05）, while ERK blockade significantly promoted microwave-induced apoptosis（P 〈 0.05） and downregulation of perforin（P 〈 0.01）. Conclusion Microwave dose-dependently induced morphological and functional injury in NK-92 cells, possibly through ERK-mediated regulation of apoptosis and perforin expression.

Feeder-free differentiation of human iPSCs into natural killer cells with cytotoxic potential against malignant brain rhabdoid tumor cells

Natural killer(NK)cells are cytotoxic immune cells that can eliminate target cells without prior stimulation.Human induced pluripotent stem cells(iPSCs)provide a robust source of NK cells for safe and effective cell-based immunotherapy against aggressive cancers.In this in vitro study,a feeder-free iPSC differentiation was performed to obtain iPSC-NK cells,and distinct maturational stages of iPSC-NK were characterized.Mature cells of CD56^(bright)CD16^(bright)phenotype showed upregulation of CD56,CD16,and NK cell activation markers NKG2D and NKp46 upon IL-15 exposure,while exposure to aggressive atypical teratoid/rhabdoid tumor(ATRT)cell lines enhanced NKG2D and NKp46 expression.Malignant cell exposure also increased CD107a degranulation markers and stimulated IFN-γsecretion in activated NK cells.CD56^(bright)CD16^(bright)iPSC-NK cells showed a ratio-dependent killing of ATRT cells,and the percentage lysis of CHLA-05-ATRT was higher than that of CHLA-02-ATRT.The iPSC-NK cells were also cytotoxic against other brain,kidney,and lung cancer cell lines.Further NK maturation yielded CD56^(-ve) CD16^(bright)cells,which lacked activation markers even after exposure to interleukins or ATRT cells-indicating diminished cytotoxicity.Generation and characterization of different NK phenotypes from iPSCs,coupled with their promising anti-tumor activity against ATRT in vitro,offer valuable insights into potential immunotherapeutic strategies for brain tumors.

Emergence of immunotherapy as a novel way to treat hepatocellular carcinoma

Tumor immunity proceeds through multiple processes, which consist of antigen presentation by antigen presenting cells(APCs) to educate effector cells and destruction by the effector cytotoxic cells. However, tumor immunity is frequently repressed at tumor sites. Malignantly transformed cells rarely survive the attack by the immune system, but cells that do survive change their phenotypes to reduce their immunogenicity. The resultant cells evade the attack by the immune system and form clinically discernible tumors. Tumor microenvironments simultaneously contain a wide variety of immune suppressive molecules and cells to dampen tumor immunity. Moreover, the liver microenvironment exhibits immune tolerance to reduce aberrant immune responses to massively-exposed antigens via the portal vein, and immune dysfunction is frequently associated with liver cirrhosis, which is widespread in hepatocellular carcinoma(HCC) patients. Immune therapy aims to reduce tumor burden, but it is also expected to prevent non-cancerous liver lesions from progressing to HCC, because HCC develops or recurs from noncancerous liver lesions with chronic inflammatory states and/or cirrhosis and these lesions cannot be cured and/or eradicated by local and/or systemic therapies. Nevertheless, cancer immune therapy should augment specific tumor immunity by using two distinct measures: enhancing the effector cell functions such as antigen presentation capacity of APCs and tumor cell killing capacity of cytotoxic cells, and reactivating the immune system in immune-suppressive tumor microenvironments. Here, we will summarize the current status and discuss the future perspective on immune therapy for HCC.

Gastric cancer-derived heat shock protein-gp96 peptide complex enhances dendritic cell activation

AIM To investigate the role of heat shock protein (HSP)glycoprotein (gp) 96 in dendritic cells (DCs) and lymphocytes induction in gastric cancer (GC). METHODS Human GC cell lines KATOIII, MKN-28 and SGC-7901 were infected with adenovirus gp96 at a multiplicity of infection of 100. gp96-GC antigen peptide complexes were purified. MTT (3-(4,5-dimethylthiazol-2-yl)2,5- diphenyltetrazolium bromide) assay, lactate dehydrogenase (LDH) release assay and enzyme-linked immunosorbent assay were used to determine allo-reactive T cell stimulation, natural killer (NK) cell activity and expression of cytokines (such as interleukin (IL)-10, IL-12, interferon (IFN)-gamma and tumor necrosis factor (TNF)-alpha), respectively. Effect of cytotoxic T lymphocyte (CTL) on DCs incubated with HSP-gp96 was also evaluated by LDH release. All assays were performed in triplicate and the average values were reported. Comparison between groups was conducted using Student's t test. RESULTS T cells incubated with HSP-gp96 exhibited a marked increase in proliferation in a dose-dependent manner (P < 0.05). NK cell activity after gp96-GC peptide complex treatment was significantly higher than that after antigen peptide treatment (P < 0.05). The activity of CTLs incubated with DCs from three GC cells lines was obviously higher than that stimulated by GC antigen at ratios of 50: 1, 25: 1, 10: 1, and 5: 1 (P < 0.05). Furthermore, the secretion of TNF-alpha, IL-10, IL-12 (P70) and IFN-alpha markedly increased after incubation with HSP-gp96 (P < 0.05). CONCLUSION HSP-gp96 promotes T cell response, enhances DC antigen presentation and induces cytokine secretion, as well. HSP-gp96 has potential as immunotherapy for elimination of residual GC cells.

Phenotypic Characteristics and Function of NK Cell Subsets in cART-Treated HIV-1-Infected Individuals

Natural killer (NK) cell plays an important role in an innate immune response against viral infection. The kinetics regulation and functional consequences of NK cells in the pathogeneses of diseases are uncertain. We analyzed NK cell distribution and function of successfully combination antiretroviral therapy (cART)-treated HIV-1 infected individuals in Khon Kaen Regional Hospital, Thailand. The results demonstrated that increased percentage and the total number of NK cell in cART-treated HIV-1 infected patients with preferential high levels of CD56dimCD16+ and CD56-CD16+ subsets when compared with a control group even in undetectable viral load (<40 copies per milliliter). Concomitantly, decreased cytotoxic activity measured by CD107asurface expression with maintained IFN-γ production implied the impairment of cytolytic activity was not recovered after cART treatment. Thus, altered NK cell frequency and function by HIV-1 infection are not completely recovered with cART, which may contribute to impaired cellular immune response and persistence of HIV-1.

Evaluation of antibody-dependent cell-mediatedcy totoxicity activity and cetuximab response in KRAS wildtype metastatic colorectal cancer patients

AIM:To investigate the prognostic role of invariant natural killer T(iNKT) cells and antibody-dependent cell-mediated cytotoxicity(ADCC) in wild type KRAS metastatic colorectal cancer(mC RC) patients treated with cetuximab.METHODS: Forty-one KRAS wt mC RC patients,treated with cetuximab and irinotecan-based chemotherapy in Ⅱ and Ⅲ lines were analyzed. Genotyping of single nucleotide polymorphism(SNP)s in the FCGR2A,FCGR3A and in the 3' untranslated regions of KRAS and mutational analysis for KRAS,BRAF and NRAS genes was determined either by sequencing or allelic discrimination assays. Enriched NK cells were obtained from lymphoprepperipheral blood mononuclear cell and iN KT cells were defined by co-expression of CD3,TCRVα24,TCRVβ11. ADCC was evaluated as ex vivo NK-dependent activity,measuring lactate dehydrogenase release.RESULTS: At basal,mCRC patients performing ADCC activity above the median level(71%) showed an improved overall survival(OS) compared to patients with ADCC below(median 16 vs 8 mo;P=0.026). We did not find any significant correlation of iN KT cells with OS(P=0.19),albeit we observed a trend to a longer survival after 10 mo in patients with iN KT above median basal level(0.382 cells/microliter). Correlation of OS and progression-free survival(PFS) with interesting SNPs involved in ADCC ability revealed not to be significant. Patients carrying alleles both with A in FCGR2 A and TT in FCGR3A presented a trend of longer PFS(median 9 vs 5 mo;P=0.064). Chemotherapy impacted both iN KT cells and ADCC activity. Their prognostic values get lost when we analysed them after 2 and 4 mo of treatment.CONCLUSION: Our results suggest a link between iN KT cells,basal ADCC activity,genotypes in FCGR2A and FCGR3A,and efficacy of cetuximab in KRAS wt mC RC patients.

Granulysin and its clinical significance as a biomarker of immune response and NK cell related neoplasms

Granulysin is a cytotoxic granular protein that was identified from human T cells by using the gene subtraction method in 1987. Based on its amino acid homology, granulysin belongs to the saposin-like protein family. The bioactive 9-k Da form of granulysin is processed from the 15-k Da pro-product in the cytoplasmic granules. It is expressed in CD8-positive αβT cells 5 d after mitogenic stimulation and constitutively in natural killer(NK) cells and γδT cells, although regulation of its expression has not yet been precisely determined. The 9-k Da granulysin form has anti-microbial activity against microorganisms such as bacteria, fungi, mycobacteria and parasites, as well as tumoricidal activity against some tumors at 1-10 μmol/L concentrations. Granulysin is secreted in both Ca-dependent and-inde-pendent manners. In sera, only the 15-k Da form is detectable and is expected to be a biomarker for immune potency, acute viral infection, anti-tumor immune reaction, acute graft vs host disease, and NK cell associated neoplasm.

The Effect of Tremella Fuciformis Spores Polysaccharides (TSP) on Immune Cellular Function of Mice in Vitro

TSP could markedly enhance the proliferative response of the murine splenocyte to LPS and induce the mitogenesis of the spleen cells.Furthermore,it was able to augment the activity of natural killer cell and ADGG;at a dosage of 25-250μg/ml,the ability of splenocytes to produce IL-2 induced by onA had been improved; at the concentration of 250μg／ml or more,TSP could inhibit the proliferative response of the murine lymphocyte to GonA and the ~3-HTdR spontaneous incorporation rate of thymocytes,and the inhibitory action ran in paralell with the increase in concentration of TSP.

Novel Strategies for Redirecting NK Cells in Cancer Immunotherapy

Natural killer(NK)cells act as a first line of defense in innate immune system against new malignant transformed cells without prior exposure to tumor antigens.The activity of NK cells is tightly controlled by a balance between inhibitory receptors and activating receptors,and when activation signals outweigh inhibitory signals,NK cells can mediate a response to eliminate the targeted cells.As a bridge between the innate and adaptive immune responses to enhance destruction of tumors,NK cells kill their tumor targets through a variety of mechanisms,including receptor-mediated cytotoxicity,antibody-dependent cell-mediated cytotoxicity(ADCC),death receptor Fas/FasL signaling pathway-mediated cancer apoptosis.However,the efficacy of using NK cells for tumor immunotherapy has been limited by a lack of antigen specificity.To overcome this limitation,Vallera and colleagues developed a bispecific killer cell engager(BiKE),which is comprised of a first ScFv that recognizes a tumor antigen and a second ScFv against CD16(expressed on NK cells)to trigger ADCC.To overcome the poor expansion of NK cells in vivo,a novel trispecific killer cell engager(TriKE)was evolved from the BiKE by the same team.In this molecule,IL-15 was integrated to promote NK cell expansion,thereby eliciting superior NK cytotoxicity and NK cell persistence in vivo compared to BiKE.In order to simultaneously target drug-refractory cancer stem cells(CSC)and cancer cells,a novel tetraspecific killer engager(TetraKE)comprising anti-CD133,EpCAM,CD16 ScFvs and a sustaining IL-15 signal cross-linker was recently developed.Compared to BiKE or TriKE,TetraKE1615EpCAM133 was highly specific against EpCAM-and CD133-bearing cells,leading to enhanced NK cell proliferation,prolonged survival and a limited cytokine response.This TetraKE represents a promising new modality for immunotherapy.

颗粒酶B在自身免疫性疾病中的作用概述

自身免疫性疾病(AID)是一类由自身免疫失衡引起的,累及多系统的慢性炎症性疾病。人群广泛发病,病因未明,且对患者本身和全民健康水平有较大影响。颗粒酶B是一类丝氨酸蛋白酶,可以广泛切割细胞内外的各种底物,可能是影响AID发生发展的重要因素。目前颗粒酶B在AID中的作用仍然有待探究,本文概述了颗粒酶B的基因结构、表达调控、进入靶细胞的机制以及在细胞内和细胞外的功能,总结了颗粒酶B在系统性红斑狼疮、类风湿关节炎、系统性硬化症、血管炎和特发性炎性肌病等多种AID中的作用。旨在对AID的病因学研究进行总结,为进一步深入展开诊断、防治和预后的研究提供思路。

NK细胞数及Th1/Th2与再生障碍性贫血的相关性研究

目的探究自然杀伤细胞(NK)数及Th1/Th2与再生障碍性贫血(AA)的相关性。方法选取2020年2月-2022年12月医院诊治的AA患者112例作为研究对象,其中重型患者52例,非重型患者60例,选择医院健康志愿者65例作为对照组,观察基本资料、NK细胞功能、Th1、Th2水平,分析NK细胞、Th1/Th2与再生障碍性贫血的相关性。结果AA组、重型AA组及非重型AA组的NK细胞数、IL-2、IL-4、TNF-α均低于对照组,IL-6高于对照组(P<0.05);重型AA组IL-10低于对照组,IFN-γ高于非重型AA组(P<0.05);AA组IFN-γ高于对照组(P<0.05)。重型AA组NK细胞数与CD4+呈正相关;IL-2与IFN-γ、IL-4呈正相关;IL-6和IFN-γ与Ret、ARC呈负相关;IL-10与CD8+呈正相关,与Β呈负相关。非重型AA组NK细胞数与CD3+、CD8+、CD4+/CD8+、Β呈正相关;IL-2与IL-4呈正相关;IL-4与Β呈负相关,与CD8+呈正相关;IL-6与WBC、Β呈负相关,与IL-10、IFN-γ呈正相关。结论AA患者NK细胞数减少,Th1/Th2细胞比例失衡,两者均与多项血液指标具有明显相关性,可能在AA免疫发病机制中发挥重要作用。

Repeated cupping manipulation temporary decreases natural killer lymphocyte frequency, activity and cytotoxicity

OBJECTIVE： Elevated natural killer lymphocyte cytotoxicity（NKc） has been linked with reproductive problems in women. Here we evaluate the potential benefit of cupping therapy（CT） in reproductionrelated immune responses.METHODS： This was a pilot clinical study. Participants were he althy fe male volunteers（n = 23） with elevated NKc, and received repeated CT 3 times over 5 d（inner pressure 40–50 kPa, 40 min; 12–1 5 cups）. Lymphocyte subsets, NKc and NK lymphocyte activity（NKa） were measured in blood on day 0（initial levels, before the first treatment） and days 3, 10 and 17 after the last CT treatment, using the K562-stimulated CD69 expression assay.RESULTS： As a result of CT manipulations NKa was reduced on days 3 and 10, and NK percentage was reduced on day 10. NKc was most sensitive to CT treatment, resulting in their decreased counts at 3, 10 and 17 d post CT. CT treatment decreased NKc in the majority of individuals（87%）, but the magnitude of the effect was variable. Out of 23 subjects 9（39.1%） had a 2–3 fold decrease of NKc on days 3, 10 and 17; 11（47.8%） started to show a decrease in NKc later, or more quickly returned to base levels; and only 3（13%） subjects displayed no effect of CT on NKc. Expectedly, no changes in T-cell subsets（CD3CD4, CD3CD8, HLADR, CD158a） were observed after CT.CONCLUSION： CT decreased NK cell numbers, their activity and cytotoxicity. Low cost, safety, noninvasive nature and ease of administration make CT a promising approach for NKc down-regulation.

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.

Multi‑omics integration identifies regulatory factors underlying bovine subclinical mastitis

Background Mastitis caused by multiple factors remains one of the most common and costly disease of the dairy industry.Multi-omics approaches enable the comprehensive investigation of the complex interactions between mul-tiple layers of information to provide a more holistic view of disease pathogenesis.Therefore,this study investigated the genomic and epigenomic signatures and the possible regulatory mechanisms underlying subclinical mastitis by integrating RNA sequencing data(mRNA and lncRNA),small RNA sequencing data(miRNA)and DNA methylation sequencing data of milk somatic cells from 10 healthy cows and 20 cows with naturally occurring subclinical mastitis caused by Staphylococcus aureus or Staphylococcus chromogenes.Results Functional investigation of the data sets through gene set analysis uncovered 3458 biological process GO terms and 170 KEGG pathways with altered activities during subclinical mastitis,provided further insights into subclin-ical mastitis and revealed the involvement of multi-omics signatures in the altered immune responses and impaired mammary gland productivity during subclinical mastitis.The abundant genomic and epigenomic signatures with sig-nificant alterations related to subclinical mastitis were observed,including 30,846,2552,1276 and 57 differential methylation haplotype blocks(dMHBs),differentially expressed genes(DEGs),lncRNAs(DELs)and miRNAs(DEMs),respectively.Next,5 factors presenting the principal variation of differential multi-omics signatures were identified.The important roles of Factor 1(DEG,DEM and DEL)and Factor 2(dMHB and DEM),in the regulation of immune defense and impaired mammary gland functions during subclinical mastitis were revealed.Each of the omics within Factors 1 and 2 explained about 20%of the source of variation in subclinical mastitis.Also,networks of impor-tant functional gene sets with the involvement of multi-omics signatures were demonstrated,which contributed to a comprehensive view of the possible regulatory mechanisms underlying subclinical mastitis.Furthermore,multi-omics integration enabled the association of the epigenomic regulatory factors(dMHBs,DELs and DEMs)of altered genes in important pathways,such as‘Staphylococcus aureus infection pathway’and‘natural killer cell mediated cyto-toxicity pathway’,etc.,which provides further insights into mastitis regulatory mechanisms.Moreover,few multi-omics signatures(14 dMHBs,25 DEGs,18 DELs and 5 DEMs)were identified as candidate discriminant signatures with capac-ity of distinguishing subclinical mastitis cows from healthy cows.Conclusion The integration of genomic and epigenomic data by multi-omics approaches in this study provided a better understanding of the molecular mechanisms underlying subclinical mastitis and identified multi-omics candidate discriminant signatures for subclinical mastitis,which may ultimately lead to the development of more effective mastitis control and management strategies.

利妥昔单抗对多发性硬化症复发期患者外周血NK细胞 功能

目的观察利妥昔单抗对多发性硬化症(MS)复发期患者外周血NK细胞活化及ADCC功能的影响及机制。方法选取MS复发期病例(n=28),并将无自身免疫疾病及重大感染疾病的受试者作为健康对照组(n=25),提取两组被检者外周血单个核细胞(PBMCs),检测利妥昔单抗处理前后B细胞、自然杀伤细胞(NK)细胞比例及NK细胞活化水平;建立PBMCs与人慢性髓源白血病细胞系K562细胞直接接触共培养体系,检测利妥昔单抗处理后NK细胞抗体依赖细胞介导细胞毒性作用(ADCC)的效应因子释放。结果利妥昔单抗能诱导MS复发期组和健康对照组外周血中B细胞和NK细胞比例显著下调,且能诱导健康对照组的NK细胞活化及ADCC功能的显著上调,但对MS复发期患者NK细胞的活化及ADCC功无明显影响。结论利妥昔单抗可诱导MS复发期患者B细胞及NK细胞比例下调,但对NK细胞的活化及其ADCC功能无明显影响。

NKG2D配体在13种肿瘤细胞系中的表达及意义

背景与目的:NKG2D及其配体的相互作用在肿瘤免疫监视中起着非常重要的作用。本研究探讨NKG2D配体在13种肿瘤细胞系中的表达及其意义。方法:采用半定量RT-PCR法检测肿瘤细胞系中NKG2D配体的mRNA表达。应用MTT法检测人NK细胞对肿瘤细胞的杀伤活性,免疫组织化学技术和Western blot法检测肿瘤细胞中MHCⅠ类相关蛋白A(MHC classⅠchain-related A)蛋白表达情况。结果:13种肿瘤细胞系表达不同水平的NKG2D配体mRNA。其中Hep2细胞中MICA强阳性表达,HeLa、HepG2、MDA231、HT29、SGC7901、M21、K562、Jurkat细胞MICA表达阳性,而Caski、PG、HL-60和Raji细胞中MICA mRNA阴性。MICA和MICB的表达水平与NK细胞杀伤活性具有高度相关性(r=0.851,P<0.001;r=0.652,P<0.05)。除ULBP3外,其余ULBP成员的表达水平与NK细胞杀伤均无相关性。结论:在6种人NKG2D配体中,MICA的表达水平与肿瘤细胞对NK细胞杀伤的敏感性关系最为密切,肿瘤细胞MICA的表达水平可能决定着机体NK细胞抗肿瘤免疫应答的强弱。

多抗甲素的药理研究进展

对近 6、7年来有关多抗甲素药理的研究进展进行综述 ,主要包括 :①调整巨噬细胞功能 ;②对人天然杀伤细胞的作用机制 ;③对人淋巴细胞免疫功能的影响 ;④对淋巴因子活化的杀伤细胞增殖及杀伤活性的影响 ;⑤增强特异性细胞毒T细胞活性 ;⑥对于动物红细胞变形能力和免疫功能的影响。

IL-2、IL-15对NK细胞亚群表型和功能的调节作用

目的 探讨IL 2和IL 15对NK细胞亚群表型和功能的调节作用。方法 采用双色免疫荧光染色和流式细胞仪分析 ,比较IL 2和IL 15对新鲜分离外周血单个核细胞 (PBMC)中NK细胞及经混合淋巴细胞培养 (MLC)活化的NK细胞表型的调节作用 ;用 4h51 Cr释放实验检测IL 2和IL 15对NK细胞杀伤水平的影响。结果 在PBMC培养中 ,当IL 2或IL 15最终为5 0U mL时 ,能明显上调PBMC中CD5 6 +NK细胞的比例 ,且IL 15对CD5 6 bright亚群增殖的促进作用强于IL 2 ;在MLC中 ,当IL 2或IL 15为 5 0U mL时 ,能够促进MLC活化的NK细胞比率的增加 ,NK细胞亚群由CD5 6 dim为主转变成CD5 6 bright为主 ,此诱导作用IL 2强于IL 15。IL 2和IL 15都能上调PBMC和MLC中NK细胞杀伤水平 ,并呈剂量依赖关系 ,在PBMC中 ,当IL 15为5 0U mL时 ,IL 15对NK细胞杀伤水平的促进作用强于IL 2 ;而在MLC中当IL 2为 5 0U mL时 ,对NK细胞杀伤水平的促进作用高于IL 15。在PBMC中 ,同时加入 5 0U mL的IL 15和IL 2 ,NK细胞杀伤率高于单独加入IL 15或IL 2。结论 IL 15促进PBMC中NK细胞向CD5 6 bright亚群分化和杀伤水平强于IL 2 ,而IL 2促进同种异体抗原诱导的活化NK细胞向CD5 6 bright亚群分化和杀伤水平则高于IL 15。这种反应格局的差别 。

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。