树突状细胞肿瘤疫苗的研究现状

本文综述了树突状肿瘤疫苗的研究及应用现状,其中主要包括树突状细胞的生物学特性、体外培养、肿瘤疫苗的制备、临床应用、存在的问题及展望等。     

树突状细胞疫苗的研究进展

树突状细胞（dendritic cell,DC）是一类强大的抗原提呈细胞,也是适应性免疫应答的关键步骤,对于诱导T、B细胞介导的细胞免疫和体液免疫是必需的。由于其特殊的免疫学功能,在DC疫苗的研究中备受关注。目前已有一种基于DC的疫苗Sipuleucel-T获批上市,还有多项DC疫苗正在临床试验阶段。本文对DC的生物学特征和功能、DC疫苗的类型以及DC疫苗面临的挑战和前景作一综述。     

循环应用低剂量环磷酰胺对黑色素瘤荷瘤小鼠调节性T细胞的影响及抗瘤作用

目的观察循环应用低剂量环磷酰胺(CTX)对黑色素瘤荷瘤小鼠调节性T细胞(Treg)的影响及抗瘤作用。方法通过皮下接种黑色素瘤细胞B16制备黑色素瘤荷瘤小鼠模型;对荷瘤小鼠分别经腹腔单次或循环注射CTX,每隔7d给药1次,共3次,应用流式细胞术检测小鼠脾脏中CD4+CD25+Foxp3+Treg的含量;培养小鼠骨髓来源的树突状细胞(DC),将DC与脾T淋巴细胞混合培养,应用ELISA法检测脾T淋巴细胞干扰素γ(IFNγ)的分泌量;同时测量肿瘤的大小,绘制肿瘤生长曲线,并观察各组荷瘤小鼠自身免疫病的发生情况。结果CTX的最佳应用剂量为100mg/kg。随着荷瘤时间的延长,荷瘤小鼠脾脏CD4+CD25+Foxp3+/CD4+的比值呈逐渐升高趋势。单次应用CTX抑制Treg的时间较短,而循环应用CTX能够延长对Treg的抑制,使其维持在相对较低的水平;循环应用CTX显著提高了荷瘤小鼠脾T淋巴细胞IFNγ的分泌水平。单次和循环应用CTX均未能延缓肿瘤的生长,两组小鼠均未见免疫性白斑及明显的化疗毒副反应。结论循环应用CTX能更加有效地调控Treg,从而促进DC对T淋巴细胞的抗原特异性激活,这将会提高DC疫苗的抗瘤效果。     

转基因树突状细胞激活细胞毒性T细胞特异性杀伤淋巴瘤的体外实验

目的 探讨转基因树突状细胞激活细胞毒性T细胞产生抗淋巴瘤的特异性细胞免疫反应。方法 采用人骨髓来源的髓系前体细胞,在人细胞因子IL-4、GM-CSF和INF-α诱导下,在体外生成大量树突状细胞。将制备好的含有IgVH1核酸质粒,用脂质体法转染树突状细胞。转染成功的树突状细胞与外周血T淋巴细胞共培养,激活特异性CTL细胞,与阳性表达IgVH1的人淋巴瘤Namalwa细胞反应,用3H-TdR掺入法观察CLLs对瘤细胞的特异性杀伤效应。结果 树突状细胞能够用脂质体方法转染IgVH1核酸质粒,并且有效递呈给外周血T细胞,对表达IgVH1的人淋巴瘤Namalwa细胞产生特异性免疫杀伤活性,与对照组相比差异有显著意义（P<0.01）。结论 体外诱导扩增的 DC能够转染 IgVH1核酸质粒,体外激活T淋巴细胞,产生特异性细胞毒效应。     

树突状细胞疫苗与宫颈癌细胞免疫治疗的新进展

宫颈癌是妇科最常见的恶性肿瘤之一,其发病率在女性恶性肿瘤中居第2位。树突状细胞(DC)是机体免疫应答的始动者,以DC为基础的抗肿瘤免疫治疗已成为热点。本文就树突状细胞的抗肿瘤机制及其在宫颈癌免疫治疗中的应用作一综述。     

调节性树突状细胞在免疫相关性疾病中的研究进展

树突状细胞(Dendritic cell,DC)是机体免疫系统中一组形态和功能异质性的专职抗原提呈细胞,其既能启动初始免疫应答,也能负向调节免疫反应。具有负向调节免疫应答功能的树突状细胞称为调节性DC(Regulatory DC,DCreg)。DCreg在某些感染性疾病、自身免疫性疾病、肿瘤等的发生发展过程中起重要作用,也有望在临床中成为重要的治疗工具。DCreg的分化与细胞所处的微环境有关,结合微环境研究DCreg才能客观地反应机体免疫功能的真实状态。本文就DCreg分化的微环境、血管活性肠肽(Vasoactive intestinal peptide,VIP)诱导的DCreg(DCVIP)以及部分DCreg在免疫相关性疾病中的临床意义等方面的最新研究进展作一综述。     

肿瘤抗原MUC1抑制骨髓来源抑制细胞产生的机制

目的探讨肿瘤抗原MUC1抑制骨髓来源抑制细胞(myeloid-derived suppressor cell,MDSC)产生的机制。方法分离C57BL/6小鼠股骨骨髓细胞,分别与稳定表达含22个串联重复序列的全长人MUC1 cDNA片段的B16细胞(B16-MUC1)和空质粒对照B16细胞(B16-neo)培养上清共培养,流式细胞术分析MUC1对MDSC产生及MDSC表达MUC1蛋白的影响;瑞氏姬姆萨染色观察MUC1对骨髓细胞生长形态的影响;流式细胞术检测共培养的骨髓细胞中单核细胞和巨噬细胞标志物CD14和F4/80的表达及成熟单核-巨噬细胞标志物CD11b和CD68的表达。结果正常C57BL/6小鼠骨髓细胞分别与B16-neo和B16-MUC1细胞培养上清共培养24和48 h后,BM+B16-MUC1组骨髓细胞中CD11b+Gr-1+MDSC数量较BM+B16-neo组均明显减少(P<0.05),共培养48 h后,BM+B16-MUC1组的CD11b+Gr-1+MDSC中MUC1蛋白的表达较BM+B16-neo组明显增多(P<0.01);BM+B16-MUC1组骨髓细胞中单核-巨噬细胞数量增多;与BM+B16-neo组相比,BM+B16-MUC1组CD14+、F4/80+和CD68+细胞表达数量明显增高(分别为P<0.01、P<0.01、P<0.05),CD11b+平均荧光强度明显增高(P<0.01)。结论 MUC1通过诱导骨髓细胞向单核-巨噬细胞分化,从而抑制MDSC的产生。     

树突状细胞与化学品过敏原筛选的研究进展

皮肤致敏性检测(皮肤变态反应试验)是一项非常重要的化学品、新材料、新产品安全检测的指标之一,鉴于过敏性反应的危害严重性而备受重视。随着人们对动物福利的关注,各种替代方法的研究方兴未艾。其重点是探讨该过程中主要的关键作用机理和基因调控机制,方可为建立新型的体外过敏测试方法提供直接的科学依据。体外方法从in chemico(DPRA)到in silico(QSAR相关方法)、RHE(体外重组表皮),都取得了一定的进展。树突状细胞(DCs)在变态反应的调控中起到重要的启动和抗原呈递作用而得到日益关注。     

慢性粒细胞白血病树突状细胞对T细胞增殖作用的研究

目的　体外诱导慢性粒细胞白血病 (CML)患者外周血单个核细胞 (PBMCs)为树突状细胞 (DCs) ,并对其形态、表型及对T细胞刺激增殖作用进行研究。方法　利用GM CSF、IL 4、TNF α体外定向诱导生成树突状细胞 ,对所诱生的细胞进行细胞表型及形态检测 ,用D FISH方法检测所诱生DCs的白血病源性 ,应用MTT法检测所诱生的DCs刺激T细胞增殖的能力。结果　CML患者PBMCs在体外可诱导生成bcr/abl融合基因阳性的DCs(CMLDCs)。CMLDCs对自体T细胞有明显刺激增殖作用 ,而CML细胞无此作用。CMLDCs刺激同一异体T细胞增殖能力弱于正常DCs,但当培养体系中加入 30 0U/ml干扰素 α(IFN α)时可使其刺激能力接近正常DCs。结论　CMLDCs具有刺激自体及异体T细胞增殖的能力 ,但对异体T细胞的刺激作用弱于正常DCs,IFN α可提高CMLDCs刺激T细胞增殖能力     

芦荟多糖对小鼠抗肿瘤作用的实验研究

目的研究中华芦荟多糖(AP)对小鼠的抗肿瘤作用。方法观察不同浓度中华芦荟多糖对移植性S180肿瘤小鼠和EAC荷瘤小鼠的抑瘤率,对EAC荷瘤小鼠肿瘤坏死因子(TNF)含量的影响,并以脾系数为指标,观察中华芦荟多糖对环磷酰胺(CTX)的增效减毒作用。结果不同浓度的中华芦荟多糖对S180荷瘤小鼠和EAC荷瘤小鼠的肿瘤均具有不同程度的抑制作用。结论中华芦荟多糖可显著改善CTX引起的机体生理机能紊乱,提高其抑瘤作用。     

Capability of Human Dendritic Cells Pulsed with Autologous Induced Pluripotent Stem Cell Lysate to Induce Cytotoxic T Lymphocytes against HLA-A33-Matched Cancer Cells

Irradiated murine induced-pluripotent stem cells (iPSCs) elicit the antitumor response in vivo. However, it is unclear whether human iPSCs would elicit antitumor effects. In the present study, we investigated the capability of human iPSC lysate (iPSL)-pulsed dendritic cells (DCs) (iPSL/DCs) to induce cancer-responsive cytotoxic T lymphocytes (CTLs) in vitro. iPSCs and DCs were induced from peripheral blood mononuclear cells isolated from a human leukocyte antigen (HLA)-A33 homozygous donor. The iPSL was pulsed with immature DCs, which were then stimulated to allow full maturation. The activated DCs were co-cultured with autologous CTLs and their responses to SW48 colorectal carcinoma cells (HLA-A32/A33), T47D breast cancer cells (HLA-A33/A33), and T98G glioblastoma cells (HLA-A02/A02) were tested with enzyme-linked immunospot (ELISPOT) assays. Comprehensive gene expression analysis revealed that the established iPSCs shared numerous tumor-associated antigens with the SW48 and T47D cells. Immunofluorescent analysis demonstrated that the fluorescent-labeled iPSL was captured by the immature DCs within 2 h. iPSL/DCs induced sufficient CTL numbers in 3 weeks for ELISPOT assays, which revealed that the induced CTLs responded to SW48 and T47D cells. Human iPSL/DCs induced cancer-responsive CTLs on HLA-A33-matched cancer cells in vitro and could be a promising universal cancer vaccine for treating and preventing cancer.     

Supplementation with Serum-Derived Extracellular Vesicles Reinforces Antitumor Immunity Induced by Cryo-Thermal Therapy

Effective cancer therapies should reshape immunosuppression and trigger antitumor immunity. Previously, we developed a novel cryo-thermal therapy through applying local rapid cooling followed by rapid heating of tumor tissue. It could not only ablate local tumors, but also, subsequently, induce systemic long-term antitumor immunity. Hyperthermia can induce the release of extracellular vesicles (EVs) to stimulate antitumor immunity. We examine whether EVs are released after cryo-thermal therapy and whether they could improve the efficacy of cryo-thermal therapy in the 4T1 model. In this study, serum extracellular vesicles (sEVs) are isolated and characterized 3 h after cryo-thermal therapy of subcutaneous tumors. sEV phagocytosis is observed in vitro and in vivo by using laser confocal microscopy and flow cytometry. After cryo-thermal therapy, sEVs are administered to mice via the tail vein, and changes in immune cells are investigated by using flow cytometry. After cryo-thermal therapy, a large number of sEVs are released to the periphery carrying danger signals and tumor antigens, and these sEVs could be phagocytosed by peripheral blood monocytes and differentiated macrophages. After cryo-thermal therapy, supplementation with sEVs released after treatment promotes the differentiation of myeloid-derived suppressor cells (MDSCs), monocytes into macrophages and CD4⁺ T cells into the Th1 subtype, as well as prolonging the long-term survival of the 4T1 subcutaneous tumor-bearing mice. sEVs released after cryo-thermal tumor treatment could clinically serve as an adjuvant in subsequent cryo-thermal therapy to improve the therapeutic effects on malignant tumors.     

Switching from Apoptosis to Pyroptosis: Gasdermin-Elicited Inflammation and Antitumor Immunity

Pyroptosis is a necrotic form of regulated cell death. Gasdermines (GSDMs) are a family of intracellular proteins that execute pyroptosis. While GSDMs are expressed as inactive forms, certain proteases proteolytically activate them. The N-terminal fragments of GSDMs form pores in the plasma membrane, leading to osmotic cell lysis. Pyroptotic cells release pro-inflammatory molecules into the extracellular milieu, thereby eliciting inflammation and immune responses. Recent studies have significantly advanced our knowledge of the mechanisms and physiological roles of pyroptosis. GSDMs are activated by caspases and granzymes, most of which can also induce apoptosis in different situations, for example where the expression of GSDMs is too low to cause pyroptosis; that is, caspase/granzyme-induced apoptosis can be switched to pyroptosis by the expression of GSDMs. Pyroptosis appears to facilitate the killing of tumor cells by cytotoxic lymphocytes, and it may also reprogram the tumor microenvironment to an immunostimulatory state. Understanding pyroptosis may help the development of cancer immunotherapy. In this review article, recent findings on the mechanisms and roles of pyroptosis are introduced. The effectiveness and limitations of pyroptosis in inducing antitumor immunity are also discussed.     

人乳头状瘤病毒16亚型E6E7基因重组腺病毒的构建及其在小鼠骨髓源树突状细胞中的表达

目的 构建人乳头状瘤病毒16亚型(Human papillomavirus 16,HPV16)E6E7基因重组腺病毒,并在小鼠骨髓源树突状细胞(Dendritic cell,DC)中表达。方法双酶切质粒pET-32a(+)-E6E7获得E6E7,基因片段,插入腺病毒穿梭质粒pAd-Track-CMV中,转染HEK293细胞,扩增病毒,经同源重组、包装后获得重组腺病毒pAd-E6E7,转染体外培养的小鼠骨髓源DC,激光共聚焦显微镜观察转染的小鼠DC的形态,流式细胞术检测转染前后小鼠DC表面标志物(CD40、CD86、MHCⅡ和CD11C),Western blot检测E6蛋白的表达。结果双酶切及测序证实,重组腺病毒质粒pAd-E6E7构建正确,插入的E6E7基因片段序列正确;转染HEK293细胞48 h,倒置荧光显微镜下可见绿色荧光蛋白的表达,重组腺病毒的滴度为3×107 CCID50/ml;重组腺病毒pAd-E6E7感染后DC的状态与成熟DC表面标志物(CD40、CD86、MHCⅡ和CD11C)相符合,感染后的DC表面有许多树枝状、刺状突起,符合成熟DC的表面形态;感染后的DC中存在E6蛋白的表达。结论已成功构建了HPV16 E6E7基因重组腺病毒表达质粒,其能在小鼠骨髓源DC中表达。     

特异性抗原致敏的DC-CIK细胞对肿瘤细胞的杀伤效应

目的检测特异性抗原致敏的DC-CIK细胞对恶性肿瘤细胞的杀伤效应。方法采用肿瘤抗原致敏的DC与CIK细胞共培养,分析其免疫表型,并用MTT染色法检测其对肿瘤细胞的杀伤力。结果所获得DC-CIK细胞的CD3异质性T细胞群,对肾透明细胞癌786-0和前列腺癌PC-3细胞的杀伤率分别为70.64%和65.65%。结论DC-CIK细胞对肾透明细胞癌786-0细胞和前列腺癌PC-3细胞具有较强的杀伤效应。     

Chemically Induced Cardiomyogenesis of Mouse Embryonic Stem Cells

A transgenic murine embryonic stem (ES) cell lineage expressing enhanced green fluorescent protein (EGFP) under the control of α‐myosine heavy chain (α‐MHC) promoter (pα‐MHC‐EGFP) was used to investigate the effects of (thio)urea and cinchona alkaloid derivatives on cardiomyogenesis. The screening of the compounds yielded cardiomyogenesis inducing substances with good ( IV‐5 , V‐4 ) to very good activities ( II‐16 , IV‐8 ), as determined by a 50 to 80 % increase in the EGFP fluorescence compared to untreated cells. Time‐dependent screening approaches in which compounds were added at different developmental stages of the ES cells appeared to be of limited suitability for the identification of potential cellular targets.     

克菌丹诱导人支气管上皮细胞转化

[方法]16HBE细胞经0.0625～1.0 mg/L剂量的克菌丹染毒,通过观察染毒细胞形态及恶性表型鉴定,检测克菌丹诱导16HBE细胞的转化.[结果]克菌丹转化第30代细胞生长速度增快,对conA凝集敏感性增强,失去贴壁生长依赖性,电镜下可见明显的形态学改变,裸鼠体内形成肿块为鳞状上皮细胞癌.[结论]克菌丹可直接诱导16HBE细胞发生恶性转化,该模型的建立为克菌丹对健康损伤效应研究及其评价奠定了基础.     

6Ckine修饰的树突状细胞促进T淋巴细胞增殖和分化的作用

目的研究次级淋巴组织趋化因子(6Ckine)修饰的树突状细胞(DC)对T淋巴细胞增殖和分化的影响。方法用携带人6Ckine基因的重组复制缺陷型腺病毒(Ad-6Ckine)感染人外周血单个核细胞来源的DC,检测Ad-6Ckine-DC对6Ckine的表达及细胞因子分泌的影响,并观察其吞噬功能和表型的变化及对自身T淋巴细胞的趋化作用。用结肠癌LoVo细胞抗原致敏Ad-6Ckine-DC,将该DC与自身T淋巴细胞共同培养,分别用3H掺入法、RT-PCR和ELISA检测Ad-6Ckine-DC对T淋巴细胞增殖和分化的影响。结果在Ad-6Ckine转染后24h内,DC的吞噬功能几乎不受影响。转染的6Ckine基因能在DC中表达,表达的6Ckine能促进其表达CD83和CCR7,上调RANTES的表达。Ad-6Ckine-DC对自身T淋巴细胞有明显的趋化作用,抗原致敏的Ad-6Ckine-DC能显著促进T淋巴细胞的增殖,并增强其表达T-bet和IL-2的能力。结论6Ckine基因的修饰能在一定程度上促进DC的成熟,并募集T淋巴细胞于DC周围,有利于DC向T淋巴细胞传递抗原和第二信息,增强DC促进T淋巴细胞增殖的作用并使其向Th1分化,诱导细胞免疫,将成为制备肿瘤疫苗的一种良好选择。     

黄芪多糖对胃癌细胞上清液中培养的树突状细胞分化成熟及功能的影响

目的探讨黄芪多糖对胃癌细胞SCG-7901上清液中培养的树突状细胞(Dendritic cells,DC)分化成熟及功能的影响,分析黄芪多糖抗癌的作用机制。方法将人外周血分离的单核细胞加入含重组人粒细胞-巨噬细胞集落刺激因子(rhGMCSF)和重组人白细胞介素的培养液中,随机分为空白组(以RPMI1640培养液培养)、干预组(以黄芪多糖干预后的胃癌细胞上清液培养)、对照组(以胃癌细胞上清液培养)。混合培养48h后,显微镜下观察DC成熟过程中的形态学变化,流式细胞术检测DC的表型(CD40、CD80),混合同种淋巴细胞增殖反应(Mixed lymphocyte reaction,MLR)检测DC的增殖效应。结果与对照组比较,空白组和干预组DC的CD40和CD80的表达均明显增加(P<0.05),刺激同种淋巴细胞增殖效应明显增强(P<0.05);干预组DC CD40和CD80的表达阳性率及刺激同种淋巴细胞增殖效应均明显低于空白组(P<0.05)。结论在体外,黄芪多糖可有效对抗胃癌细胞上清液引起的对DC分化成熟和功能的抑制。