肿瘤基因工程纳米疫苗NL(MH)抗肿瘤复发的实验研究

目的：在小鼠体内观察纳米疫苗NL（MH）抗肿瘤复发作用。方法：以PBS、空白脂质体、MH、MH／NL、NL（MH）免疫C57BL／6小鼠3次后，IFN-γ ELISPOT和LDH杀伤实验检测纳米疫苗激活小鼠特异性细胞免疫反应的情况；以肿瘤攻击实验和肿瘤切除后复发实验来评价纳米疫苗预防肿瘤复发作用。结果：与对照组相比，NL（MH）组小鼠脾淋巴细胞中分泌IFN-γ的T细胞数量明显增多（P〈0．05），CTL对B16-MAGE3细胞具有显著的特异性杀伤作用；在肿瘤攻击实验中，NL（MH）组B16-MAGE3肿瘤成瘤时间长、成瘤率低；肿瘤切除后，NL（MH）组B16-MAGE3肿瘤复发时间延迟，复发率明显降低。结论：NL（MH）能够刺激机体产生强烈的MAGE3特异性的细胞免疫反应，对表达MAGE3的肿瘤细胞具有显著的杀伤作用，能有效预防B16-MAGE3切除后复发。     

小鼠肝癌 H-22 细胞膜相关抗原肽提取物的抑瘤作用及其免疫机制的研究

目的应用小鼠肝癌 H-22 细胞膜相关抗原肽(TAP)提取物免疫小鼠,观察其对小鼠自身移植肿瘤生长及免疫学参数的影响,为制备肿瘤疫苗提供实验依据.方法采用微酸洗脱法制备相对分子质量≤3×103的细胞膜 TAP 提取物,皮下免疫小鼠,检测胸腺细胞周期时相和T细胞亚组百分数的变化;并检测脾细胞 Con A 反应性、IL-2 和 IFN-γ分泌活性、CTL 杀伤活性的变化,以及脾脏 T 细胞 CD3、CD69 和 TCR 的表达和抑瘤效应.结果TAP 提取物免疫后,移植肿瘤的发生率降低,平均出现时间延迟,生长速度减慢;同时,脾细胞 CD69表达增加,Con A 反应性、IFN-γ和 IL-2 分泌活性和 CTL 杀伤活性不同程度增强;胸腺细胞 CD3 表达显著增高、CD+4 和 CD+8 T 细胞百分数也不同程度增高.结论小鼠肝癌 H-22 细胞膜 TAP 提取物具有免疫原性,能有效激发免疫系统功能,抑制自身移植肿瘤的生长.     

自体肿瘤瘤苗对荷瘤鼠Th1、Th2型细胞因子及细胞毒作用的影响

目的研究经处理的H22肝癌细胞肿瘤瘤苗作为全细胞瘤苗对H22荷瘤小鼠体内Th1/Th2细胞比例和细胞因子的影响以及CTL的杀伤活性.方法用加重组白细胞介素2、重组粒细胞单核细胞集落刺激因子及福氏不完全佐剂制成疫苗,建立荷瘤小鼠模型,用51Cr释放法测定瘤苗免疫组、荷瘤组、正常组小鼠脾细胞对亲本H22肝癌细胞的杀伤活性;流式细胞仪检测单个核细胞中的Th1和Th2细胞,并取血检测血清中IL-10、IFN-γ水平.结果效靶比为200:1时,免疫小鼠脾细胞体外杀伤亲本H22肝癌细胞的杀伤率为38.3%,显著高于荷瘤组的13.6%,正常组的7.5%,以及对S180细胞的9.1%(P均＜0.05).瘤苗免疫组Th1细胞及Th1/Th2细胞的比值显著升高(P＜0.01),血清IFN-γ较对照组明显升高(P＜0.01);血清IL-10较对照组明显降低(P＜0.01).结论肿瘤细胞加小剂量IL-2和GM-CSF及佐剂组成的肿瘤细胞瘤苗可激发特异性细胞介导的免疫反应,改善抗肿瘤免疫反应.     

肝癌H-22细胞膜抗原肽提取物对小鼠免疫功能的影响及其抑瘤作用

目的应用小鼠肝癌H-22细胞膜相关抗原肽(TAP)提取物免疫小鼠,观察其对小鼠自身移植肿瘤生长及免疫学参数的影响,为制备肿瘤疫苗提供实验依据.方法采用微酸洗脱法制备分子量≤3000 Da的细胞膜TAP提取物,皮下免疫小鼠,检测胸腺细胞增殖反应、T细胞亚组百分数的变化,脾细胞Con A反应性、IL-2和IFN-γ活性、CTL杀伤活性的变化及抑瘤效应.结果 TAP提取物免疫后,移植肿瘤的发生率降低(P＜0.01),平均出现时间延迟(P＜0.001),生长速度减慢;同时,脾细胞Con A反应性(P＜0.01)、IFN-γ(P＜0.05)和IL-2分泌活性和CTL杀伤活性(P＜0.05)不同程度增强;胸腺细胞3H-TdR自发掺入率(P＜0.05)及CD4 和CD8 T细胞百分数(P＜0.05)也有不同程度增高.结论小鼠肝癌H-22细胞膜TAP提取物具有免疫原性,能有效激发免疫系统功能,抑制自身移植肿瘤的生长.     

髓系抑制性细胞对神经母细胞瘤抗原特异性细胞毒性T淋巴细胞体外增殖和杀伤抑制作用北大核心CSCD

目的探讨髓系抑制性细胞(myeloid-derived suppressor cell,MDSC)对神经母细胞瘤抗原特异性细胞毒性T淋巴细胞(cytotoxic T lymphocyte,CTL)体外增殖和杀伤活性的影响。方法体外培养神经母细胞瘤SK-N-SH细胞、自BALB/c小鼠分离培养树突状细胞(dendritic cell,DC)和CD3+T细胞,制备DC诱导的神经母细胞瘤抗原特异性CTL。分离纯化小鼠MDSC,将CTL与MDSC混合培养,采用CFSE荧光染色和流式细胞学方法,检测MDSC对CTL增殖抑制情况。将CTL与SK-N-SH、MDSC混合培养,ELISA法检测不同组CTL对SK-N-SH杀伤率及上清液中IL-2和IFN-γ分泌情况。结果磁珠分选纯化后Gr-1+CD11b+MDSC细胞比例为84.6%。负载抗原的CTL细胞上清液中IL-2和IFN-γ含量较单纯培养T细胞上清液中IL-2和IFN-γ含量明显增高(P<0.05)。与MDSC共培养的CTL细胞增殖明显受抑;而单独培养CTL随时间延长细胞增殖明显。MDSC+CTL+SK-N-SH组杀伤率较CTL+SK-N-SH组明显降低(t=6.506,P<0.001);两组上清液中IL-2和IFN-γ分泌量差异亦有统计学意义(均P<0.01)。结论 MDSC可抑制神经母细胞瘤抗原特异性CTL的体外增殖和活性而产生免疫耐受,抑制CTL对神经母细胞瘤细胞的杀伤作用。     

ehCGβ肿瘤基因疫苗诱生的效应脾细胞过继免疫抗肿瘤作用的研究

目的:探讨ehCGβ肿瘤基因疫苗诱生的效应脾细胞过继免疫在抗肿瘤中的作用.方法:通过转染建立稳定表达ehCGβ和HBV-preS2/S的细胞株Sp2/0-ehCGβ和Sp2/0-preS2/S.以TR421-hCGβ质粒实施基因免疫,免疫后检测小鼠脾细胞,特异性细胞毒活性;同期将脾细胞过继免疫给正常小鼠,以过继TR421-hCGβ质粒免疫小鼠脾细胞为实验组、过继TR421质粒免疫小鼠脾细胞为对照组,检测脾细胞杀伤效应.结果:效应脾细胞对SP2/0-ehCGβ的杀伤率明显高于Sp2/0-preS2/S(P＜0.05).Sp2/0-ehCGβ在实验组小鼠仅2只形成实体瘤,TR421-hcGβ质粒基因免疫抗肿瘤任用有肿瘤特异性,两组有显著性差异(P＜0.05),而在对照组小鼠均形成实体瘤.Sp2/0-preS2/S在所有的小鼠均形成了实体瘤,其瘤重无显著性差异.结论:ehCGβ肿瘤基因疫苗诱生的效应细胞可特异性杀伤肿瘤,过继免疫效应细胞能使正常小鼠获得明显的特异性抗肿瘤能力.     

携带SEA和CD80双基因的重组腺病毒转染B16细胞体外诱导T淋巴细胞活化的研究

目的:观察恶性黑色素瘤B16细胞经重组腺病毒感染后,表达在B16细胞膜上的SEA和CD80体外能否诱导免疫学反应。方法:B16细胞分别经空载体腺病毒Ad(空)和重组腺病毒Ad-MMRE-mTERT-B7、Ad-MMRE-mTERT-SEA、Ad-MMRE-mTERT-BIS感染后,和小鼠脾淋巴细胞共培养,然后,采用Brdu 酶联免疫法（ELISA）检测淋巴细胞增殖;流式细胞术检测T淋巴细胞亚群增殖;ELISA法检测细胞因子IL-2、TNF-α和IFN-γ的产生。结果:与感染空载体腺病毒Ad(空)和未感染B16细胞相比,经重组腺病毒感染的B16细胞体外能够显著诱导脾淋巴细胞的增殖,其中CD3⁺CD4⁺和CD3⁺CD8⁺T淋巴细胞增殖显著;细胞因子TNF-α、IFN-γ和IL-2的产生显著升高;CTLs对肿瘤细胞的杀伤活性显著增强;表达双基因的B16细胞体外诱导免疫应答的能力高于单基因过表达B16细胞。结论:B16细胞经重组腺病毒感染后,表达在细胞膜上的SEA和CD80具有免疫学活性,本研究为今后进一步采用所构建重组腺病毒进行恶性黑色素瘤的免疫基因治疗提供了实验依据。     

融合基因pEGFP-C3-B7.2-hTERT诱导小鼠免疫应答及抑制肝癌移植瘤

目的：构建融合DNA疫苗pEGFP-C3-B7．2-hTERT，观察其诱导小鼠免疫应答的能力和抗小鼠肝癌H22细胞移植成瘤的作用。方法：通过RT-PCR扩增B7．2和hTERT cDNA，以pEGFP-C3为载体构建pEGFP-C3-B7．2-hTERT融合基因质粒，肌肉注射接种C57BL／6小鼠，间隔7d，共3次，以注射接种pEGFP-C3-B7．2、pEGFP-C3-hTERT、pEGFP-C3和PBS为对照。检测免疫小鼠脾淋巴细胞CTL杀伤活性、脾细胞培养上清IL-2和IFN-γ水平、外周血淋巴细胞亚群变化及血清中抗hTERT抗体水平。将融合基因pEGFP-C3-B7．2-hTERT免疫已负荷肝癌细胞H22／hTERT或H22／B7．2的小鼠，观察小鼠成瘤时间、生存时间。结果：琼脂糖凝胶电泳、酶切及序列测定证实，成功构建了融合基因质粒pEGFP-C3-B7．2-hTERT。融合基因免疫小鼠的脾淋巴细胞对B7．2-hTERT阳性靶细胞的杀伤活性明显高于各对照组（P〈0．01），每只pEGFP-C3-B7．2-hTERT免疫小鼠都产生了抗体，免疫鼠外周血CD4^＋、CD8^＋ T细胞和脾细胞培养上清中Th1类细胞因子IFN-γ、IL-2水平较各对照组明显升高（均P〈0．01）。pEGFP-C3-B7．2．hTERT融合基因质粒免疫已负荷肝癌细胞H22／hTERT或H22／B7．2的小鼠后，小鼠60d未成瘤，其他各组22d时所有小鼠均已成瘤，60d时均死亡。结论：DNA疫苗pEGFP-C3-B7．2-hTERT在体内能诱导出明显的B7．2-hTERT特异性的抗肿瘤免疫应答，且能抑制体内已经存在的少量肿瘤细胞的成瘤。     

融合基因mGM-CSF/hIL-2在肝癌细胞瘤苗特异性免疫治疗中的作用

背景与目的:手术切除是治疗肝癌的主要方法,但对其术后的复发转移却无更好的办法。近年来,免疫学的发展使肝癌的治疗有了更好的治疗方法。本研究旨在通过制备人白细胞介素2(hIL-2)与鼠粒-单核细胞集落刺激因子(mGM-CSF)融合基因修饰的H22肝癌瘤苗,观察其特异性抗肿瘤免疫作用。方法:用含hIL-2与mGM-CSF融合基因的真核表达载体,在体外转染H22细胞,制成疫苗,皮下接种小鼠,同时建立荷瘤小鼠模型。用51Cr释放法测定瘤苗免疫组、空载组、未转染组小鼠脾细胞对亲本H22细胞的杀伤活性。取血检测血清中IL-10、IFN-γ水平,观察小鼠存活期。结果:成功制备了含有hIL-2与mGM-CSF融合基因的H22肝癌瘤苗。免疫小鼠脾细胞体外对H22细胞的杀伤率为38.3%,显著高于对S180细胞的9.1%,以及空载组和未转染组的13.6%和7.5%(P<0.05)。转基因瘤苗免疫组血清IFN-γ为(12.83±0.75)pg/mL,较空载瘤苗组的(7.83±0.65)pg/mL明显升高(P<0.01),血清IL-10[(4.58±0.34)pg/mL]较空载瘤苗组的(8.15±0.28)pg/mL明显降低(P<0.01)。同时,转基因瘤苗免疫组小鼠存活期为(40±6)d,较对照组[空载瘤苗组(30±3)d,未转染组(19±4)d]明显延长。结论:转染hIL-2与mGM-CSF融合基因的同系肿瘤细胞瘤苗可激发特异性细胞介导的免疫反应,改善抗肿瘤免疫反应,延长荷瘤小鼠存活期。     

腺病毒介导IL-2基因转染的瘤苗体内抗肿瘤作用

目的 :探讨重组腺病毒介导的 IL- 2基因转染的瘤苗的体内抗肿瘤作用及其免疫学机制。方法 :应用腺病毒介导的鼠 IL- 2基因转染 CT2 6小鼠结肠癌细胞 ,灭活后用作瘤苗治疗荷瘤小鼠 ,观察皮下肿瘤生长及其存活期。采用乳酸脱氢酶释放法检测荷瘤小鼠脾细胞 CTL、L AK、NK细胞的杀伤活性。结果 :鼠 IL- 2基因转染瘤苗治疗能显著抑制荷瘤小鼠皮下肿瘤生长并明显延长其存活期 (P<0 .0 1)。体内免疫功能检测表明 ,鼠 IL- 2基因转染疫苗治疗组小鼠脾细胞 CTL 活性、L AK活性和 NK活性显著高于对照组 (P<0 .0 1)。结论 :腺病毒介导鼠 IL- 2基因转染的瘤苗体内具有较强的抗肿瘤效应 ,其机制可能是提高了荷瘤小鼠特异性和非特异性抗肿瘤免疫反应     

THE BIOLOGICAL CHARACTERISTICS OF ADENOVIRUS-MEDIATED IL-18 GENE-MODIFIED MURINE COLORECTAL ADENOCARCINOMA CELL IN VIVO AND IN VITRO

Interleukin 18 (IL-18) has multiple biological activities, such as promoting the generation of Th1 cytokines and GM-CSF, activating NK cells and CTL, which contributes to its anti-tumor activity.[1(5] So IL-18 might have promising application in the immunotherapy and gene therapy of cancer. To confirm the anti-tumor activity of IL-18, we constructed the recombinant adenovirus encoding IL-18 gene, observed preliminarily the biological characteristics of IL-18-modified murine colorectal …     

Direct Activation of Human CD8+ Cytotoxic T Lymphocytes by Interleukin-18

Direct activation of human cytotoxic T lymphocytes (CTL) by interleukin (IL)-18 was observed in a system in which CTL effective against autologous tumor cells were generated. Peripheral blood mononuclear cells (PBMC) from tumor-bearing patients, after removal of natural killer (NK) cells, were cultured in a medium containing IL-1, -2, -4, and -6, with or without IL-18, and stimulated with autologous tumor cells. IL-18 increased the activity of the CTL and the proportion of autologous CD8⁺ T cells present after 28 days in the induction culture. When purified CD8⁺ T cells were cultured in the presence of IL-18 and IL-2 for 7 days, the CTL showed enhanced cytotoxic activity against autologous tumor cells. Moreover, a purified CD8⁺ T cell population, which did not exhibit any apparent cytotoxic activity against autologous tumor cells, displayed cytotoxic activity after 7-day incubation with IL-18. These results suggest that IL-18 may be useful to generate autologous CTL in humans and may thereby contribute to adoptive immunotherapy for tumors.     

米托蒽醌处理B16F10-ESAT-6-gpi/IL-21瘤苗特征及其诱导的抗肿瘤免疫反应初探

背景与目的:蒽环类药物处理可使肿瘤细胞免疫原性增加。本文旨在分析米托蒽醌(mitoxantrone,MIT)处理的B16F10-ESAT-6-gpi/IL-21瘤苗特征,初步探讨该瘤苗诱导的抗肿瘤免疫反应。方法:MIT处理B16F10-ESAT-6-gpi/IL-21瘤苗后,用吖啶橙/嗅化乙啶(AO/EB)染色法观察瘤苗细胞形态,流式细胞仪(FCM)检测其粒度及凋亡比例,荧光显微镜观察瘤苗凋亡后细胞膜表面结核杆菌早期分泌靶抗原6KD(ESAT-6)的表达情况,蛋白质印迹法(Western blot)检测瘤苗经MIT处理后IL-21的表达。瘤苗免疫小鼠后,FCM检测了补体依赖的细胞毒性(complement dependent cytotoxicity,CDC)及细胞毒T细胞(cytotoxicT lymphocyte,CTL)活性。结果:经MIT处理后,瘤苗停止分裂,细胞逐渐增大,数日内可保持生物活力,并表达IL-21。瘤苗细胞凋亡后,ESAT-6成点簇状分布于胞膜表面。MIT处理的瘤苗能诱导小鼠产生抗肿瘤免疫应答,免疫鼠血清和CD8+T细胞可分别通过CDC和CTL杀伤野生型B16F10细胞。结论:MIT处理的B16F10-ESAT-6-gpi/IL-21瘤苗失去增殖能力,但仍能表达IL-21且具有免疫原性,能诱导小鼠产生抗肿瘤免疫反应。     

肿瘤疫苗与白介素-12联合免疫治疗小鼠肉瘤的研究

目的:探讨混合热休克蛋白(HSP)/肽与白介素-12(IL-12)和环磷酰胺(CTX)联合治疗小鼠肉瘤的作用及机制。方法:以S-180肉瘤为模型,将瘤组织剪碎,裂解,离心,取上清经Sephacryl S-200层析,截取相对分子质量(50～200)×103段,经SDS-PAGE电泳及Western-blot法鉴定。用提取的HSP/肽免疫小鼠后,再用低剂量CTX及IL-12治疗(强化疫苗),观察无瘤生存率、抑瘤生长率、抑制转移率和存活期。用流式细胞仪,ELISPOT及乳酸脱氢酶等方法检测免疫功能的变化。结果:HSP疫苗与IL-12和CTX联合治疗小鼠S-180肉瘤,80.0%肿瘤完全消退,且100.0%抑制了肺部转移,达长期生存,而对照组全部在40d内死亡。检测表明HSP/肽疫苗形成了免疫预存,从而使IL-12和CTX发挥了抗瘤作用。结论:HSP/肽与IL-12和CTX联合治疗诱发了机体细胞免疫功能,产生强大的抗瘤作用,可能具有临床应用前景。     

Interleukin-7 Enhances the in Vivo Anti-tumor Activity of Tumor-reactive CD8+ T cells with Induction of IFN-gamma in a Murine Breast Cancer Model

Interleukin-7 (IL-7) is a potent anti-apoptotic cytokine that enhances immune effector cell functionsand is essential for lymphocyte survival. While it known to induce differentiation and proliferation in somehaematological malignancies, including certain types of leukaemias and lymphomas, little is known about itsrole in solid tumours, including breast cancer. In the current study, we investigated whether IL-7 could enhancethe in vivo antitumor activity of tumor-reactive CD8+ T cells with induction of IFN-γ in a murine breast cancermodel. Human IL-7 cDNA was constructed into the eukaryotic expression plasmid pcDNA3.1, and then therecombinational pcDNA3.1-IL-7 was intratumorally injected in the TM40D BALB/C mouse graft model. Serumand intracellular IFN-γ levels were measured by ELISA and flow cytometry, respectively. CD8+ T cell-mediatedcytotoxicity was analyzed using the MTT method. Our results showed that IL-7 administration significantlyinhibited tumor growth from day 15 after direct intratumoral injection of pcDNA3.1-IL-7. The anti-tumoreffect correlated with a marked increase in the level of IFN-γ and breast cancer cells-specific CTL cytotoxicity.In vitro cytotoxicity assays showed that IL-7-treatment could augment cytolytic activity of CD8+ T cells fromtumor bearing mice, while anti-IFN-γ blocked the function of CD8+ T cells, suggesting that IFN-γ mediated thecytolytic activity of CD8+ T cells. Furthermore, in vivo neutralization of CD8+ T lymphocytes by CD8 antibodiesreversed the antitumor benefit of IL-7. Thus, we demonstrated that IL-7 exerts anti-tumor activity mainly throughactivating CD8+ T cells and stimulating them to secrete IFN-γ in a murine breast tumor model. Based on theseresults, our study points to a potential novel way to treat breast cancer and may have important implicationsfor clinical immunotherapy.     

腺病毒转染黑色素瘤抗原基因3的树突状细胞疫苗抗胃癌的免疫效应

目的 研究趋化因子巨噬细胞炎症蛋白1α(MIP-1α)动员的树突状细胞(DC),经黑色素瘤抗原基因3(MAGE-3)腺病毒转染后对胃癌细胞的免疫效应.方法 615小鼠尾静脉注射MIP-1α,分选得到B220-CD11c+细胞,加入细胞因子连续培养,检测其细胞表面标志和混合淋巴细胞反应(MLR).收集培养后的B220-CD11c+细胞,加入编码MAGE-3的重组腺病毒进行转染,制备表达肿瘤抗原的DC疫苗,以荷载小鼠前胃癌(MFC)全肿瘤细胞抗原制备的DC疫苗作为阳性对照.采用二苯基溴化四氮唑蓝(MTT)法,榆测活化的T淋巴细胞在体外对MFC细胞的杀伤作用.采用酶联免疫吸附试验(ELISA),检测γ干扰素(INF-γ)的分泌情况.DC疫苗皮下注射MFC荷瘤小鼠,观察小鼠瘤体生长情况和存活时间.结果 MIP-1α注射后,外周血中B220-CD11c+细胞明显升高.新鲜分离的B220-CD11c+细胞在体外经过细胞因子诱导分化后具有典型的DC表面标志,并在MLR中具有极强的刺激T淋巴细胞增殖的能力.腺病毒转染MAGE-3的DC激活的T淋巴细胞表现出对MFC细胞的特异性杀伤作用,产牛高水平的INF-γ[(1460.00±16.82)ps/ml].实验组荷瘤小鼠接受DC疫苗治疗后,肿瘤牛长缓慢,观察至MFC细胞接种后的第27天,其肿瘤体积仅为(3.46±1.12)cm3;实验组小鼠的肿瘤体积与对照组之间的差异有统计学意义(P<0.01).实验组小鼠存活时间明显延长,与对照组之间的差异有统计学意义(P<0.01).结论 注射趋化因子MIP-1α可快速动员并诱导分化为成熟DC.肿瘤抗原基因MAGE-3经腺病毒转染制备的DC疫苗,在体外可以诱导出针对胃癌细胞的特异性杀伤作用,在体内对MFC荷瘤小鼠有明显的免疫治疗作用.     

Anti-Tumor Efficacy of Gene Vaccine Expressing PSMA

OBJECTIVE To observe anti-tumor effects of PVAX-PSMA gene vaccine.METHODS The PSMA gene was inserted into a mammalian expression vector, PVAX-1, to construct the DNA vaccine candidate, and was then used to vaccinate C57BL/6 mice. Animals vaccinated with PVAX-1 and NaCl were used as controls.Anti-PSMA antibody was detected in sera of the animals. The proliferation and cytotoxicity of the spleen cells were observed. The immunized mice were inoculated with RM-1 cells. The mice were inoculated with RM-1 cells, and then the mice were immunized. The anti-tumor efficacy of the gene vaccine was evaluated by the ratio of tumor formation, tumor volume, tumor mass before and after gene vaccination and evaluated by survival rate of the immunized mice.RESULTS High level of anti-PSMA antibody was induced in the PVAX-PSMA group. The splenocytes from PVAX-PSMA group were stimulated to produce strong proliferation responses and significant cytotoxic T-cells (CTL) activity. After the mice were immunized with PVAX-PSMA gene, tumor occurrence was decreased, and the growth velocity of tumor was markedly reduced, resulting in prolonged tumor-free time (P < 0.05).CONCLUSION PVAX-PSMA gene vaccine has significant antitumor effects and provides an experimental basis for primary prevention and immunotherapy of prostate cancer.     

雷公藤内酯醇对人宫颈癌细胞的凋亡诱导效应

目的:探讨腺病毒介导AFP基因修饰的DC(AFP-DC)瘤苗经不同途径免疫后机体抗肿瘤免疫应答反应.方法:采用皮下注射、静脉注射和瘤体注射三种途径回输AFP-DC瘤苗,比较观察AFP-DC瘤苗对荷瘤小鼠免疫治疗作用,应用4h51cr释放杀伤实验、T细胞与NK体内剔除实验等方法,观察AFP-DC瘤苗对荷瘤小鼠免疫治疗作用及保护性免疫反应.结果:皮下注射AFP-DC瘤苗治疗效果在抑制肿瘤生长、延长小鼠存活期方面都明显优于瘤体内注射或尾静脉注射(P＜0.05),AFP-DC瘤苗体内能更有效地诱导特异CTL细胞毒活性,能使免疫动物产生一定的免疫保护作用,抵抗肿瘤细胞的再攻击.在AFP-DC瘤苗诱导抗肿瘤免疫排斥反应过程中,必需有CD4 T和CD8 T细胞的参与;而在其效应阶段,则依赖于CD8 T细胞的参与,CD4 T细胞为非必需;在免疫诱导及效应阶段剔除NK细胞对抗肿瘤免疫应答无明显影响.结论:皮下注射AFP-DC瘤苗能有效诱导机体产生抗肿瘤免疫反应,为DC介导的肝癌免疫治疗开辟了新的途径.     

黑色素瘤抗原与肺癌的免疫治疗

随着分子生物学及基因工程技术的出现及应用 ,肿瘤疫苗的研究已成为主动性免疫治疗的重要手段之一。黑色素瘤抗原 (MAGE)为肿瘤特异性CTL所能识别的抗原 ,该类抗原上特定的肽段可与相应的HLAⅠ类分子结合 ,引起强烈的CTL反应。由于大多数肺癌高表达MAGE ,因而应用MAGE抗原肽对肺癌患者进行免疫治疗 ,可能具有广阔的应用前景。     

Spleen-derived dendritic cells engineered to enhance interleukin-12 production elicit therapeutic antitumor immune responses

The major goal in cancer immunotherapy is the induction of tumor-specific T lymphocytes capable of killing tumor cells. As both dendritic cells (DCs) and interleukin-12 (IL-12) can play immunostimulatory roles in vivo, the use of a combination of these has become a promising approach. In the present study, we used a murine tumor model to examine whether spleen-derived DCs transduced with the IL-12 gene could elicit tumor-specific immune responses. BALB/c mice injected peritumorally with adenovirus-mediated IL-12 gene-transduced antigen-unpulsed DCs inhibited the growth of day 5-established subcutaneous CT26 tumors. Splenocytes from treated mice responded specifically to parental tumor cells and showed increased production of interferon gamma (IFN-gamma) and antitumor cytotoxic T-lymphocyte (CTL) activity. Increased numbers of both CD4(+) and CD8(+) T cells were detected in the treated tumors. The inhibition of tumor growth was significantly greater in mice injected with IL-12 gene-transduced DCs than in those injected with IL-12 gene-transduced fibroblasts or the IL-12 gene-encoding adenovirus itself. Taken together, these results indicate that DCs transduced with the IL-12 gene by a recombinant adenovirus are effective in inducing tumor-specific Th1 and CTL responses that inhibit the growth of established subcutaneous tumors.