体外培养的树突状细胞与细胞因子诱导的杀伤细胞相互作用的研究

目的 观察同源的树突状细胞（DC）与细胞因子诱导的杀伤（CIK）细胞于体外同一培养体系共同培养时的相互影响,为临床联合应用DC和CIK细胞进行肿瘤生物治疗提供依据.方法 用无血清培养基进行DC和CIK细胞的体外培养制作,共同培养1 w后,检测CIK细胞免疫表型、杀瘤活性的变化以及DC分泌IL-12的变化.结果 DC与CIK细胞的共培养会增加CIK细胞的CD3CD56双阳性细胞的比例和非特异性增强对K562细胞的杀伤活性;同时增强DC分泌IL-12的能力.结论 体外共培养DC与CIK细胞可相互增强抗肿瘤免疫活性.     

树突状细胞增强细胞因子诱导的杀伤细胞抗神经胶质瘤细胞作用及机制研究

目的探讨细胞因子诱导的杀伤细胞（CIK）与树突状细胞（DC）共培养后DC-CIK混合细胞抗神经胶质瘤细胞的免疫作用。方法分离健康人外周血单个核细胞,分别于体外诱导DC和CIK,然后共培养成DC-CIK细胞。实验分DC组、DC-CIK组、DC-T组和CIK组。Elisa试剂盒检测各组培养上清中IL-12和IFN．1的含量,流式细胞仪检测细胞表型,CCK一8法体外检测对神经胶质瘤细胞的杀伤活性。结果DC-CIK组培养上清中IL-12和IFN-1的含量分别为（110．24±2．22）mg／L和INF·Y／（913．46±20．64）mg／L,明显高于其它三组（P〈0．05）。DC—CIK组cDi细胞（61．34-1．31）％、CD3／CD56细胞（29．4±1．03）％也明显增加（P〈0．05）。对神经胶质瘤细胞的杀伤活性,DC—CIK组为（54．67±2．62）％,与DC组（19．44±1．07）％、DC—T组（21．27±1．85）％和CIK组（36．52±2．06）％比较,差异有统计学意义（P〈0．05）。结论DC—CIK细胞能诱导明显的神经胶质瘤细胞杀伤活性,为颅内肿瘤的免疫治疗提供了依据。     

NDV联合负载胃癌细胞抗原DC-CIK对胃癌细胞的杀伤效果及机制

目的探讨新城疫病毒（NDV）联合负载胃癌细胞抗原（Ag）的树突状细胞（DC）及细胞因子诱导的杀伤细胞（CIK）对胃癌细胞的杀伤效果及机制。方法用人外周血单个核细胞诱导培养DC及CIK,体外培养人胃癌细胞SGC-7901,反复冻融法制备胃癌细胞Ag悬液冲击致敏DC,CIK与负载胃癌细胞Ag的DC共培养。建立胃癌裸鼠模型,将其随机分为四组各6只。PBS组瘤内注射PBS100μl／只;NDV组瘤内注射NDV0．25ml／只;Ag-DC-CIK组瘤内注射负载抗原的DC诱导的CIK细胞0．2ml／只;NDV＋Ag-DC-CIK组先瘤内注射NDV0．25ml／只,1d后再注射负载抗原的DC诱导的CIK细胞0．2ml／只;各组均隔日注射1次,共3次。14d后测量肿瘤体积,计算抑瘤率。观察肿瘤坏死情况并评分。结果NDV＋AS—DC-CIK组肿瘤平均体积小于NDV组和Ag—DC-CIK组,抑瘤率、肿瘤坏死面积评分高于NDV组和Ag-DC—CIK组;P均〈0．05。结论NDV和负载胃癌细胞Ag的DC-CIK能协同杀伤胃癌细胞,杀伤效果强于二者单用效果;其机制为NDV可增加胃癌细胞的抗原性,为CIK细胞提供更多靶点。     

树突状细胞瘤苗对老年非小细胞肺癌自体癌细胞的杀伤作用

目的研究老年非小细胞肺癌（NSCLC）患者的树突状细胞（dendritic cell,DC）瘤苗对细胞因子诱导的杀伤细胞（cytokines-induced killers,CIK）的促生长作用,及CIK在体外对患者自身肿瘤细胞的杀伤作用。方法提取老年NSCLC患者外周血单个核细胞（peripheral blood mononuclear cells,PBMC）,分别培养成DC与CIK;将患者自身的肿瘤组织分离,培养出肿瘤细胞,制备肿瘤细胞冻融物作为抗原,用于负载DC,制备成Ag-DC,同时以单纯DC作为对照,各组DC经OK-432激活后,流式细胞仪检测DC表面分子的表达;将DC与CIK共培养,制备成DC-CIK、Ag-DC-CIK,同时以单纯CIK作为对照,四氮唑盐（MTT）法测定各组CIK对自身肿瘤细胞的杀伤力。结果负载肿瘤细胞冻融抗原的Ag-DC其表面CD1a、CD80、CD86、CD83、人类主要组织相容性抗原（HLA-DR）的表达上调,明显高于未负载肿瘤抗原的DC（P〈0.05）。各组DC与CIK共培养后,Ag-DC-CIK的增殖速度明显加快,其中CD3＋CD56＋细胞的含量增加,对自身肿瘤细胞的杀伤力亦明显加强,其作用均强于其他各组DC-CIK及CIK（P〈0.05）。结论老年NSCLC患者PBMC来源的DC在负载自身肿瘤细胞冻融抗原后,可分化为成熟DC,该DC可促进CIK的增殖,提高CIK对自身肿瘤细胞的杀伤力。     

DC与CIK或LAK联合对结肠癌细胞株SW480杀伤作用的研究

[目的]研究树突状细胞(DC)联合细胞因子诱导或未诱导的杀伤细胞(CIK)或淋巴因子激活的杀伤细胞(LAK)对结肠癌细胞株SW480的杀伤活性.提供DC联合CIK或LAK治疗结肠癌的实验依据.[方法]取人外周血分离出单个核细胞(PBMNC),诱导生成DC、CIK、LAK细胞;流式细胞仪检测DC经SW480肿瘤抗原冲击后的表型变化;以CIK+DC细胞、CIK细胞、LAK+DC细胞及LAK细胞作为效应细胞,SW480为靶细胞,以15∶1、30∶1、45∶1为效靶比,LDH释放法测定细胞杀伤试验活性;ELISA检测杀伤试验中干扰素γ(IFN-γ)、白细胞介素2(IL-2)、IL-12、IL-17的分泌水平.[结果]流式细胞仪检测DC经SW480肿瘤抗原冲击后,其表面分子HLA-DR、CD40、CD80和CD86表达分别平均为90.23％、73.68％、85.96％、57.55％,与未经肿瘤抗原冲击DC比较,DC成熟的表面标志分子表达明显增加(P＜0.01).相同效靶比下,CIK+DC细胞组对SW480的杀伤作用最强,明显高于其他细胞组(P＜0.01);CIK+ DC细胞组在效靶比为45∶1时,杀伤活性最强(P＜0.01);单独CIK细胞组的杀伤活性明显高于LAK+DC细胞组(P＜0.01);LAK+ DC细胞组的杀伤活性明显高于单独LAK细胞组(P＜0.01).效靶比为45∶1时,各杀伤试验细胞组上清液中IFN-γ、IL-2、IL-12、IL-17的分泌量,CIK+DC细胞组的IFN-γ、IL-12的分泌量显著高于其他细胞组(P＜0.05);LAK+DC、单独LAK细胞组IL-2的分泌量明显高于CIK+DC、单独CIK细胞组(P＜0.05);单独CIK细胞组IFN-γ的分泌量明显高于LAK+DC、单独LAK细胞组(P＜0.05).[结论]CIK+DC细胞组对SW480的杀伤活性明显强于单独CIK、LAK+ DC组、单独LAK细胞组.其机制可能是,SW480抗原致敏的DC分泌IFN-γ、IL-12等刺激、诱导CIK细胞的活化和增殖,明显增强CIK细胞杀伤SW480的活性.     

脐血DC与CIK共培养对白血病K562细胞杀伤活性的影响

目的观察细胞因子诱导的杀伤细胞（CIK）与同源树突状细胞（DC）共培养后DC—CIK细胞的增殖活性、表型的变化及其对白血病K562细胞杀伤活性的影响。方法采集健康产妇分娩正常足月胎儿脐血50ml,密度梯度离心法分离出脐血单个核细胞培养。收集非贴壁细胞用于诱导培养CIK,贴壁细胞诱导分化出成熟DC;将成熟DC和CIK按1：5的比例混合培养3d,用MTT法检测Dc—CIK共培养细胞对白血病K562细胞杀伤活性。结果DC与CIK共培养后,DC—CIK细胞群的增殖活性和杀伤活性明显高于单纯CIK。结论DC—CIK共培养可明显提高CIK增殖活性和细胞毒作用。     

树突细胞-细胞因子诱导的杀伤细胞在抗肿瘤生长免疫治疗中的应用

目的研究树突细胞(DC)与细胞因子诱导的杀伤细胞(CIK)在抗肿瘤生长免疫治疗中的应用情况。方法采集26例恶性肿瘤患者外周血进行细胞培养与回输,随机分为观察组(PC、CIK回输)和对照组(CIK回输)。采用流式细胞仪检测细胞免疫表型、采用酶联免疫吸附试验(ELISA)双抗体夹心法检测干扰素(IFN)-γ、白细胞介素(IL)-12、肿瘤坏死因子(TNF)-α细胞因子水平,记录患者不良反应与疗效。结果观察组CD3~+/CD8~+细胞、CD3~+/CD56~+细胞双阳性细胞比例显著高于对照组(P<0.05);CIK细胞的IFN-γ、IL-12、TNF-α细胞因子均显著低于DC-CIK细胞(P<0.05);观察组不良反应率显著低于对照组、治疗效果显著优于对照组(P<0.05)。结论肿瘤患者免疫结构受损,DC-CIK免疫功能优于单纯CIK;DC-CIK生成IFN-γ、IL-12、TNF-α细胞因子能力强、杀伤肿瘤细胞效果优;DC-CIK免疫治疗可有效缓解治疗中发热、发量减少、白细胞数量降低等副作用。     

树突状细胞与细胞因子诱导的杀伤细胞共培养对白血病耐药细胞杀伤作用的实验研究

目的探讨负载P-糖蛋白(P-gp)高表达的多药耐药(MDR)白血病K562/A02细胞冻融抗原的树突状细胞(DC)与同源细胞因子诱导的杀伤细胞(CIK)共培养对MDRK562/A02杀伤作用的影响。方法提取健康人骨髓单个核细胞,常规诱导出DC及CIK,将K562/A02细胞冻融物作为抗原冲击的DC,与CIK共培养作为实验组,抗原不冲击的DC与CIK共培养作为对照组,以CIK及DC单独培养分别作为空白对照组1和空白对照组2。光镜下观察细胞形态,流式细胞术分析细胞表型,MTT法检测杀伤活性。结果实验组、对照组细胞增殖活性均大于CIK组(P<0.05)。实验组对K562/A02、K562的杀伤活性在效靶比5∶1、10∶1、20∶1时分别为(42.90±0.67)%、(49.85±0.28)%、(63.36±0.46)%和(23.56±0.43)%、(26.11±0.34)%、(34.46±0.35)%,均高于对照组及空白对照组1(P<0.05);实验组对K562/A02的杀伤活性高于K562和MCF7(P<0.05)。结论DC与CIK共培养物是一种增殖活性和细胞毒活性高于CIK的免疫活性细胞,而经冻融抗原冲击的DC与CIK共培养能明显提高对MDRK562/A02的杀伤活性。     

DC-CIK共培养在AL化疗后免疫治疗中的应用及其对NKG2D表达的影响

目的观察树突状细胞(DC)—细胞因子诱导的杀伤细胞(CIK)共培养用于急性白血病(AL)化疗后免疫治疗的疗效,及其对自然杀伤(NK)细胞表面活化受体NKG2D表达的影响。方法 31例AL患者经诱导治疗骨髓达完全缓解后,给予DC-CIK共培养治疗。治疗前后检测外周血中T细胞亚群表达、血清IL-2、IL-12、TNF-α、IFN-γ水平及外周血中NKG2D的表达。结果所有患者治疗结束后骨髓均处于完全缓解状态;DC-CIK共培养治疗后,CD3+、CD3+CD8+、CD3+CD5+6/CD1+6高于治疗前(P均<0.05);血清IL-2、IL-12、TNF-α、IFN-γ水平高于治疗前(P均<0.05);外周血单个核细胞中NKG2D阳性表达率为25.41%±8.47%,高于治疗前的8.07%±2.02%(P<0.05)。结论 DC-CIK共培养用于AL化疗后的免疫治疗效果较好,能更有效地清除微小残留病灶,提高外周血中NKG2D的表达,纠正AL细胞对自体NK细胞的免疫编辑作用。     

转移性乳腺癌单纯化疗与化疗联合DC-CIK细胞免疫治疗的疗效

目的对比分析树突细胞(DC)-细胞因子诱导杀伤(CIK)细胞免疫治疗晚期转移性乳腺癌的临床疗效。方法采用DC-CIK与常规化疗间隔进行的方案,选择41例转移性乳腺癌患者进行研究,分为单纯化疗组(应用TA方案)与联合治疗组(DC-CIK联合TA方案)。对两组的缓解率(RR)、化疗毒副反应、免疫功能及生活质量进行比较。DC及CIK细胞由自体外周血单个核细胞诱导产生,同时应用流式细胞术检测两组患者生物治疗前后外周血T细胞亚群及NKT细胞。结果 DC-CIK细胞免疫治疗回输后除个别患者出现低热外,未观察到患者出现严重不良反应。与单纯化疗组相比,联合治疗组病人的免疫力与生活质量显著提高,疾病控制率(DCR)有所提高,近期疗效好。结论 DC-CIK细胞免疫治疗副作用小,与化疗相结合,可提高疾病控制率及患者的生活质量,改善患者的免疫状况。     

Effect of DC-CIK cell on the proliferation,apoptosis and differentiation of leukemia cells

Objective:To observe the effect of co-culture cytokine-induced killer cells(CIK) and homologous dendritic cells(DC) on the proliferative activity and phenotype change of the DCCIK cell and the cell killing activity of leukemia HL-60.Methods:50 mL cord blood sample was obtained from infants delivered by full term healthy woman and the cord blood mononuclear cells were isolated by density gradient centrifugal ion.Non-adherent cells were collectedfor the induction culture of CIK.adherent cells were differentiated into mature DC;cultured mature DC was mixed with and CIK in the proportion of 1:5 for 12 d.killing activity of DC-CIK co-cultured cell on leukemia HL-60 was detected by MTT assay.Results:Compared with CIKs.the cocultured DC-CIKs presented a markedly higher proliferation and killing activity.Conclusions:Co-culture of DC-CIK cells led to a significant increase of the proliferation and cytotoxicity of CIK.     

Antitumor activities of human autologous cytokine—induced killer（CIK）cells against hepatocellular carcinoma cells in vitro and in vivo

AIM：To characterize the anticancer function of cytokine induced killer cells(CIK) and develop an adoptive immunotherapy for the patients with primary hepatocellular carcinoma(HCC),we evaluated the proliferation rate phenotype and the antitumor activity of human CIK cells from healthy donors and HCC patients in vitro and in vivo.METHODS:Peipheral bolld mononuclear cells(PBMC) form healthy donors and patients with primary HCC were incubated in vitro and induced into CIK cells in the presence of various cytokines such as interferon-gamma(IFN-γ),interleukin-1(IL-1),IL-2,and monoclonal antibody(mAb) against CD3.The phenotype and characterization of CIK cells were identified by folw cytometric analysis.The cytotoxicity of CIK cells was detemined by ^51Cr release assay.RESULTS:The CIK cells were shown to be a heterogeneous population with different cellular phenotypes.The percentage of CD3^+/CD56^+ positive cells,the dominant effector cells,in total CIK cells from healthy donors and HCC patients,significantly increased form 0.1-0.13% at day 0 to 19.0-20.5% at day 21 incubation,which suggested that the CD^3+ CD56^+positive cells proliferated faster than other cell populations of CIK cells in the protocol used in this study.After 28 day in vitro incubation,the CIK cells from patients with HCC and healthy donors increased by more than 300-fold and 500-fold in proliferation cell number respectively,CIK cells originated from HCC patients possessed a higher in vitro antitumor cytotoxic activity on autologous HCC cells than the autologous lymphokine-activated killer(LAK) cells and PBMC cells,In in vivo animal experiment.CIK cells had stonger effects on the inhibition of tumor growth in Balb/c nude mice bearing BEL-7402-producing tumor than LAK cells(mean inhibitory rate 84.7%VS52.8%,P&lt;0.05) or PBMC(mean inhibitory rate 84.7%VS 37.1%,P&lt;0.01).CONCLUSION:Autologous CIK cells are of highly efficient cytotoxic effcetor cells against primary hepatocellular carcinoma cells and might serve as an alternative adoptive therapeutic strategy for HCC patrents.     

DC-CIK联合化疗治疗晚期非小细胞肺癌的近期疗效观察

目的探讨DC-CIK联合化疗及常规化疗治疗晚期NSCLC患者的近期疗效。方法 64例临床确诊的晚期NSCLC患者随机分为两组,治疗组给予DC-CIK联合化疗,对照组给予常规化疗。观察治疗前后细胞免疫指标变化、KPS和疗效,及不良反应。结果治疗组CD 3＋、CD 4＋免疫学指标治疗前后比较,具有显著性差异（P值分别为0.018,0.047）,而CD 8＋、CD 4＋/CD 8＋无显著性差异;对照组CD 3＋、CD 4＋、CD 8＋、CD 4＋/CD 8＋免疫学指标治疗前后比较,无显著性差异。治疗组有效率43.75%,对照组有效率34.38%（P〉0.05）。治疗组KPS有效率84.4%,对照组KPS有效率62.5%（P〈0.05）。结论 DC-CIK联合化疗可明显改善晚期NSCLC患者外周血淋巴细胞亚群水平,能增加患者的临床疗效,提高患者的生活质量。     

脐血DC-CIK共培养体外抗肿瘤效应及趋化性的实验研究

目的探讨细胞因子诱导的杀伤细胞（CIK）与同源树突状细胞（DC）共培养后对人白血病K562细胞、人淋巴瘤raji细胞、人乳腺癌MCF-7细胞的杀伤作用及CIK细胞的趋化性。方法采集健康产妇分娩的正常足月胎儿脐血,分离单个核细胞,诱导培养CIK、DC细胞。将成熟DC和CIK混合培养3d,用MTT法检测CIK、DC-CIK对K562、raji、MCF-7细胞的杀伤活性;趋化试验检测CIK细胞的趋化性。结果 CIK、DC-CIK细胞对K562、raji、MCF-7细胞均具有较强的杀伤作用,DC-CIK杀伤活性明显高于CIK。趋化试验显示,IL-8、MCP-1作用后穿过微孔滤膜的细胞数明显高于阴性对照。结论 DC-CIK共培养可明显提高CIK对K562、raji、MCF-7细胞的杀伤作用,IL-8、MCP-1对CIK细胞存在趋化性。     

脐血树突状细胞介导的食管癌疫苗实验研究

目的　用杂交瘤技术制备脐血树突状细胞 (DC)和食管癌细胞融合疫苗 ,分析其生物学特征及体外诱导特异性免疫应答的能力。方法　 2 0 0 2 - 0 12 0 0 3- 0 3汕头大学医院第一附属医院分离脐血CD3 4 干细胞并诱导扩增为成熟DC ,并与EC10 9细胞融合 ,免疫磁珠法筛选EC10 9 DC ;流式细胞术鉴定疫苗表型 ;绘制疫苗生长曲线 ;MTT法测定瘤苗诱导淋巴细胞增殖能力及体外特异性免疫应答能力。结果　疫苗可体外生长 ,高表达CD80 、CD83 和CD86,并能有效刺激淋巴细胞增殖反应 ,体外诱导细胞毒T细胞 (CTL)对EC10 9的杀伤活性显著高于对照组 (P <0 0 5 )。结论　EC10 9 DC具备了刺激免疫细胞活化的分子表型 ,能在体外刺激淋巴细胞增殖和诱导特异性CTL杀伤作用     

Effects of dendritic cells from cord blood CD34^＋ cells on human hepatocarcinoma cell line BEL-7402 in vitro and in SCID mice

AIM: To develop a cancer vaccine of dendritic cells derived from human cord blood CD34+ cells and to investigate its cytotoxicity on human hepatocarcinoma cells in vitro and in sever combined immunodeficiency (SCID) mice. METHODS: Lymphocytes from cord blood or peripheral blood were primed by DCs, which were derived from cord blood and pulsed with whole tumor cell lysates. Nonradiative neutral red uptake assay was adopted to detect the cytotoxicity of primed lymphocytes on human hepatocartinoma cell line BEL-7402 in vitro. The anti-tumor effect of primed lymphocytes in vivo was detected in SCID mice, including therapeutic effect and vaccination effect. RESULTS: The cytotoxicity of DC vaccine primed lymphocytes from cord blood or peripheral blood on human hepatocarcinoma cell line BEL-7402 was significantly higher than that of unprimed lymphocytes in vitro (44.09% vs 14.69%, 47.92% vs 19.44%, P<0.01). There was no significant difference between the cytotoxicity of primed lymphocytes from cord blood and peripheral blood (P>0.05). The tumor growth rate and tumor size were smaller in SCID mice treated or vaccinated with primed lymphocytes than those with unprimed lymphocytes. SCID mice vaccinated with primed lymphocytes had a lower tumor incidence (80% vs 100%, P<0.05) and delayed tumor latent period compared with mice vaccinated with unprimed lymphocytes (11d vs 7 d,P<0.01). CONCLUSION: Vaccine of cord blood derived-DCs has an inhibitory activity on growth of human hepatocarcinoma cells in vitro and in SCID mice. The results also implicate the potential role of cord blood derived-DC vaccine in clinical tumor immunotherapy.     

Enhanced lytic activity of cytokine-induced killer cells against multiple myeloma cells after co-culture with idiotype-pulsed dendritic cells

BACKGROUND AND OBJECTIVES: There are numerous reports of in vitro and in vivo usage of dendritic cells (DC) pulsed with idiotype, the tumor-specific antigen of multiple myeloma (MM), for immunotherapy of MM. Data suggest that not only T-cells, but also the innate immune system reacts against MM. Here, we examined the cytotoxic activity of cytokine-induced killer (CIK) cells against myeloma cells. This heterogeneous effector population consists of T-, NK- and NKT-cells. DESIGN AND METHODS: CIK cells generated from buffy coats or blood from patients with MM were co-cultured with autologous idiotype-pulsed DC. The cytotoxic activity was investigated in lactate dehydrogenase release assays against cell lines or autologous CD138 positive cells from bone marrow. RESULTS: CIK cells were able to lyse MM cells at low effector to target ratios. This effect was significantly enhanced by co-culturing with specifically pulsed DC (83.8% lysis at an effector to target ratio of 16:1). Using an interferon-g secreting MACS separation assay, the cytotoxic activity of CIK cells was enhanced to maximal lysis at the lower effector to target ratio of 5:1. High cytotoxic activity was also shown in a completely autologous setting against enriched CD138+ cells from a patient with MM (54.4% lysis at an effector to target ratio of 6:1). Interestingly, there was no cytotoxic activity against the CD138- fraction of the bone-marrow. INTERPRETATION AND CONCLUSIONS: Using a heterogeneous population of effector cells, we were able to activate the innate and the adoptive immune-system against myeloma cells. CIK cells showed high lytic activity against MM cells, which could be enhanced by co-culturing with antigen-specific pulsed DC.     

Bone marrow mesenchymal stem cells reduce the antitumor activity of cytokine-induced killer/natural killer cells in K562 NOD/SCID mice

Adoptive cellular immunotherapy is an important treatment to eliminate residual tumor cells after hematopoietic stem-cell transplantation. Bone marrow mesenchymal stem cells (MSC) have previously been shown to exert immunoregulation functions, including inhibition of proliferation and killing activities of T cells and natural killer (NK) cells in vitro and reduction of the graft-versus-host disease. MSC can survive in vivo for a long period of time, the influence of MSC on the antitumor activity of subsequently infused immune killer cells is not clear. The aim of this study was to investigate the influences of MSC infused via different paths and at different times on the antitumor activities of cytokine-induced killer (CIK)/NK cells derived from umbilical cord blood in K562 NOD/SCID mice. The potential interaction mechanisms of MSC and CIK/NK cells infused through different paths using different intervals in vivo were subsequently explored. The results show that the antitumor activities of CIK/NK cells was inhibited by MSC when injected via the same path (tail vein), and the suppressive effect of MSC on CIK/NK cells were less pronounced when they were injected separately through different paths. There were no effects of MSC on the antitumor activities of CIK/NK cells if the MSC and CIK/NK cells were injected with a 48-h interval. Moreover, the suppressive effect continuous, even if MSC were infused 48 h earlier than CIK/NK cells. It suggests that pre-injected MSC can reduce the antitumor activities of CIK/NK cells in vivo. The probable mechanisms are that MSC and CIK/NK cells might have a greater opportunity to meet and interact if they are injected simultaneously via the same path. The suppression of MSC on CIK/NK cells in vivo mainly takes place in the reticuloendothelial system, including the lung and the liver.