Preliminary study on the cooperation of IL-6 and mB7-1 in the induction of effective antitumor immunityin vitro

Summary To find a new way for gene therapy against tumors with weak immunogenicity, the effect of mB7-1 costimulation alone, or combined with IL-6, in inducing antitumor immunityin vitro was investigated. It was found that mB7-1 cD-NA transfected B16 cells (B16-mB7-1) induced the expansion of effector lymphocytes and the generation of specific lytic activity more effectively than wild type B16 melanoma cells (B16-wt) or mock-transfected B16 cells (B16-neo) did. (P < 0. 01), IL-6 could effectively stimulate lymphocytes proliferation, but failed to enhance its cytotoxicity, while the combination of mB7-1 and IL-6 increased both lymphocyte proliferative response and T-cell-mediated cytotoxicity more significantly than B7-1 or IL-6 did alone (P<0. 01). It was inferred that the costimulatory molecule B7-1 is required for the activation and proliferation of T lymphocytes; the expression of mB7-1 in tumor cells could increase their immunogenicity and induce effective antitumor immune response, and the combination of B7-1 and IL-6 could induce more effective antitumor immunity, indicating that cooperation of IL-6 and mB7-1 plays a role in T lymphocyte activation. This project was supported by a grant from National Educational Committee Foundation of China (No. JW 9312).     

Experimental study on the antitumor effect of mouse B7-1 gene

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小鼠B7-1和B7-2基因转染EL4细胞瘤苗抗肿瘤免疫作用的比较研究

目的：研究冠状动脉分流（CABG）术后冠状动脉竞争血流对左乳房内动脉（LIMA）桥血流中内皮素（ET）、一氧化氮（NO）含量的影响，探讨动脉桥血管早期衰坏的分子机制。方法：建立猪CABG术后桥血管竞争血流动物模型，利用血流闭塞器造成冠状动脉不同程度狭窄，测量桥血管血流量及方向变化，并采用放射免疫分析法及硝酸还原酶法分别检测LIMA桥血流中ET、NO含量并进行对比分析。结果：冠状动脉左前降支（LAD）近端狭窄程度越轻，LIMA桥血流量越少；LAD近端未完全闭塞时，LIMA桥均出现双向血流。CABG术后LIMA桥血流ET含量明显高于移植前(P＜0.05)，NO含量明显低于移植前(P＜0.05)。LAD近端冠脉竞争血流越大，LIMA桥血流NO含量越低。LIMA桥血流NO含量与LIMA桥血流量呈正相关（r=0.957,P＜0.05）。LAD近端30％狭窄时，NO含量明显低于LAD近端90％狭窄及全部闭塞时(P＜0.05)，LAD近端50％狭窄时，NO含量明显低于LAD近端全部闭塞时(P＜0.05)。LIMA桥血流ET含量有随LAD近端冠脉竞争血流增加而升高的趋势，但差异无统计学意义（P＞0.05）。结论：来自未完全闭塞冠状动脉的竞争血流可引起LIMA桥血流量下降，产生双向血流，并导致桥血流中NO含量显著下降。     

双表达B7-1、B7-2基因肿瘤疫苗治疗小鼠肝癌优于单表达疫苗的研究

目的:研究B7-1、B7-2基因对肿瘤的免疫治疗作用。方法:应用转染有B7-1、B7-2基因的肝癌细胞株H22/B7-1、H22/B7-2,建立小鼠肝癌模型,观察小鼠成瘤期、荷瘤小鼠存活期及肿瘤结节大小。结果:各实验组动物都发生肿瘤,接种H22/B7-1 H22/B7-2组成瘤率低,对照组动物肿瘤呈进行性生长;组间成瘤潜伏期不同,与对照组相比,凡接种有H22/B7-2的小鼠肿瘤形成有迟发性;接种转B7基因细胞的小鼠肿瘤生长都较对照组慢;同时接种H22/B7-1和H22/B7-的小鼠能负载大于107的肿瘤细胞。转基因细胞在体外刺激淋巴细胞增殖和诱导CTLs的能力明显增强。结论:B7-1、B7-2都能增强肝癌细胞的免疫原性。B7-2在抗肿瘤早期发挥作用,B7-1随后起放大和调节作用。B7-1与B7-2联用效果优于单一应用。     

腺病毒介导多基因对大鼠脾淋巴细胞毒作用的影响

目的 研究含多基因（p53、GM-GSF、B7-1、IL-2）的重组腺病毒载体Ad-multigenes,对大鼠脾脏淋巴细胞毒作用的影响及对淋巴细胞分泌IL-2的刺激作用。方法 应用人外周血淋巴细胞和肿瘤细胞混合培养,分析导入目的基因的肝癌细胞系体外刺激人T淋巴细胞分泌IL-2的作用;利用大鼠脾淋巴细胞杀伤活性试验,分析导入目的基因的大鼠癌肉瘤Walker256细胞,其名疫原性的变化。结果 导入Ad-multigenes的肝癌细胞系体外刺激人外周血T淋巴细胞分泌IL-2的水平增加,导入Ad-multigenes的大鼠Walker256细胞,能增加大鼠脾脏淋巴细胞的杀辛本瘤细胞活性。结论 腺病毒介导多基因Ad-multigenes、能增加大鼠癌肉瘤Walk-er256细胞的免疫原性,和T细胞分泌IL-2的水平增加。     

Therapeutic antitumor response to cervical cancer in mice immunized with U14 v accines transfected with costimulatory B7 gene

Objective To investigate the effect of U14 vaccine transfected with the B7 gene in inducin g antitumor immune response to murine cervical carcinoma in Chinese 615-strain mice.Methods A recombinant retroviral plasmid vector expressing mouse B7-1 gene (pLNSX-mB7) was transfected into 615-strain mouse cervical carcinoma cell line No. 14 (U1 4) by electroporation to set up a highly-expressed mB7-1 U14 cell clonal strai n (B7(+)U14). In vivo experiments: (1) B7(+)U14 vaccine was primed to protect t he 615-strain mice against U14 re-challenge. (2) B7(+)U14 vaccine was injecte d into tumor-bearing mice with different tumor sizes. Lifetimes and tumor s izes were recorded. In vitro cytotoxicity assay: Mice were immunized with B 7(+)U14 or U14 vaccine and 2 weeks later, spleen cells of those mice were cultur ed for 2 days. The cytotoxicity of these cells against U14 was detected by 5-d iphenyl tetrazolium bromide assay.Results We obtained several B7-1 high expression clonal U14 lines. In vivo experiment, we did not find tumor growing in 3 of the 6 mice primed by B7(+)U14 vaccine during their entire life after re-challenge with U14. The other 3 mice develo ped tumors and their average survival time was longer than that of the control g roup (P&lt;0.01). All 6 mice grew tumors in the control group. When the transplanted tumors became palpable, the mice were randomly divided into 3 group s to be injected with B7(+)U14 vaccine. It was effective for tumor-bearing mic e only when the tumor diameters were &lt;3 mm. When the diameters were ≥3 mm, it was not efficacious to inject B7(+)U14 vaccine (P&lt;0.05). In vitro cytotoxicity assay, cytotoxic T lymphocytes induced by B7(+)U14 vaccine h ad a high er cytotoxicity against U14 than that induced by U14 vaccine (F=310.8, P &lt;0.001).Conclusions Vaccines of cervical cancer cells transfected with the costimulatory molecule B7 gene can induce antitumor immune protection in host mice against U14 re-challe nge. This treatment may cure part of the tumor-bearing mice but be restricted by tumor size. The results suggest that transfecting the B7 gene into cervical cancer as a cell vaccine may be an efficient supplementary method to treat cervi cal cancer after operation.     

IL-6和B7双基因转染的小鼠EL-4肿瘤细胞诱导抗肿瘤免疫作用

目的:探讨IL-6和B7双基因转染的小鼠肿瘤疫苗是否具有协同的抗肿瘤效应.方法:利用含小鼠B7分子和人IL-6分子cDNA的逆转录病毒载体pLmB7SN和pLhIL-6SN分别转染包装细胞株CRIP,经G418抗性筛选后以含有B7或IL-6外源基因的病毒颗粒感染小鼠EL-4胸腺瘤细胞,观察EL-4-IL-6、EL-4-B7、EL-4-IL-6+B7细胞在同基因宿主体内的致瘤性及作为抗肿瘤疫苗的能力.结果:相对亲本肿瘤细胞EL-4而言,单基因和双基因转染的EL-4细胞在小鼠体内的生长速度均明显减慢,小鼠存活时间均有一定延长,3种转基因的EL-4细胞经X-射线灭活后免疫小鼠,虽均未能阻止随后接种的EL-4细胞的生长,但小鼠存活时间都明显延长,IL-6和B7双基因转染的EL-4肿瘤细胞在抗肿瘤活性方面与IL-6或B7单基因转染的EL-4细胞差异无显著性.结论:与单基因表达疫苗比较,双基因表达疫苗没有表现出协同的抗肿瘤效应.     

共刺激分子B7-2对小鼠肝癌治疗作用的实验研究

目的 :应用转染有小鼠B7- 2基因片段的肝癌细胞 ,建立小鼠肝癌模型 ,观察小鼠肿瘤生长和消退情况 ,研究共刺激分子B7- 2对肿瘤的免疫治疗作用。方法 :建立BALB/c小鼠转B7- 2基因肝癌细胞株H2 2 /B7- 2 ,细胞计数法测定肿瘤细胞体外增殖能力 ;BALB/c鼠皮下接种H2 2 /B7- 2及野生型H2 2细胞H2 2 /Wt,以空载体转染细胞H2 2 /neo为对照 ,建立小鼠肝癌模型 ,观察小鼠成瘤期、荷瘤小鼠存活期及肿瘤结节大小 ;同源淋巴细胞肿瘤细胞混合培养 (MTLCs)后测定淋巴细胞增殖指数和CTLs活性 ,同时测定培养上清IL -2、IFNγ ,研究B7- 2分子的抗肿瘤免疫效果。结果 :细胞在体外增殖能力一致 (P =0 .782 ) ;当接种不同肿瘤细胞后 ,三组动物都发生肿瘤 ,接种H2 2 /B7- 2组肿瘤形成有迟发性 ,并在接种 18d后肿瘤都开始缩小 ,但最终不会完全消失 ;接种H2 2 /Wt和H2 2 /neo组动物肿瘤呈进行性生长。H2 2 /B7- 2在体外刺激淋巴细胞增殖和诱导CTLs的能力明显强于对照细胞 (P <0 .0 5 )。结论 :共刺激分子B7- 2能增强肝癌细胞的免疫原性 ,它在抗肿瘤早期发挥作用。用其治疗肝癌是有效的 ,但不能介导完全和长期的抗肿瘤效应。     

B7特异性siRNA对树突状细胞功能的影响

目的探讨体外合成的B7特异性小干扰RNA（siRNA）对树突状细胞（DC）功能的影响。方法设计并合成B7特异性siRNA,在脂质体的介导下转染树突状细胞,转染后72h收集细胞,用蛋白印迹法检测B7-1、B7-2蛋白的表达,用ELISPOT检测DC与淋巴细胞共培养后T细胞分泌IFN-γ,用MTT法检测混合淋巴细胞增殖反应和CTL特异性杀伤率。结果Western Blot结果显示转染72h后,siRNA1对B7-1蛋白表达的抑制率为（80．9±5．23）％;siRNA2对B7-2蛋白表达的抑制率为（74．7±4．63）％。经转染B7-1、B7-2分子特异性siRNA的DC激活后,T淋巴细胞分泌IFN-γ分别为（84．6±23．1）10^3／L和（76．7±19．7）10．3U／L明显低于对照组（204．5±46．2）10^3U／L;各组DC刺激淋巴细胞增殖指数（PI）分别为1．73±0．32和1．53士0．25,也低于对照组4．23±0．74。CTL杀伤实验结果表明：对照组的特异性杀伤率为（76．4±7．6）％,siRNA1和siRNA2组的特异性杀伤率分别为（14．4±3。6）％和（18．6士4．7）％,低于对照组。结论B7特异性siRNA可明显抑制树突细胞B7基因的表达,并可降低DC激活T淋巴细胞增殖和CTL的细胞毒性,为进一步研究siRNA诱导免疫耐受和治疗自身免疫性疾病提供了新思路和方法。     

小鼠B7-H4重组腺病毒的构建及鉴定

目的:利用AdEasyTM XL system构建携带小鼠B 7-H4基因的重组腺病毒,并鉴定其生物学活性.方法:以RT-PCR方法从C5 7小鼠肺组织中扩增B7-H4全长基因并克隆到T载体,然后测序鉴定.经Xhol Ⅰ和EcoR Ⅴ双 酶切后接入pshuttle-CMV穿梭载体(简称PSC),构建重组腺病毒的穿梭质粒PSC-mB7-H4 ,并电转化至BJ5183-AD-1感受态细菌,经筛选获得携带mB7-H4的重组腺病毒的质粒pmB7 -H4/Ad.将此质粒转化人胚肾细胞(AD-293)产生复制缺陷的重组腺病毒mB7-H4/Ad .以RT-PCR及Western blot方法检测被mB7-H4/Ad感染的AD-293细胞中B7-H4 mRNA和蛋 白的表达,并观察重组腺病毒感染的小鼠成纤维细胞(L929)对T细胞增殖和细胞因子表达的影响. 结果:获得序列准确的mB7-H4基因并成功构建重组腺病毒表达质 粒,转化AD-293细胞获得重组腺病毒;细胞生物学实验证实,该重组腺病毒具有抑制CD3单抗诱导的T淋巴细胞的增殖和细胞因子的分泌. 结论:成功构建具有免疫抑制功能的mB7-H4重组腺病毒.     

黏蛋白1(MUC1)致敏的树突状细胞疫苗体外抗肿瘤实验研究

目的 研究以CpG作为免疫佐剂,应用黏蛋白1（MUC1）致敏树突状细胞（DC）制备疫苗在体外诱导的特异性抗肿瘤作用。方法 健康人外周血采用密度梯度离心法,分离外周血单核细胞（PBMC）,应用GM-CSF、IL-4、TNF-α等细胞因子体外培养诱导DC,观察细胞形态,并通过流式细胞术检测成熟DC细胞标志物CD80、CD86。再应用CpG作为免疫佐剂,MUC1作为抗原致敏DC制备疫苗,致敏的DC与T细胞混合培养,观察其诱导T淋巴细胞增殖能力。诱导产生的细胞毒性T淋巴细胞（CTL）与肿瘤靶细胞以5：1、10：1、20：1的效靶比共孵育,MTT法检测CTL杀伤活性。结果 DC表型检测结果为CD80+细胞占70.4％,CD86⁺细胞占72.0％,呈现成熟DC表型。MUC1致敏的DC疫苗与淋巴细胞混合培养显示,DC疫苗具有刺激T细胞增殖活化的作用,其中DC+CpG+MUC1组明显高于MUC1+DC或CpG+DC组,差异有统计学意义（P<0.01）。DC疫苗诱导产生的特异性CTL对肿瘤细胞的杀伤作用较单独T细胞组或DC组明显增强,差异有统计学意义（P<0.01）。并随着效靶比增大,其杀伤作用呈逐渐增强。结论 经CpG和MUC1致敏的DC疫苗在体外可诱导产生特异性抗肿瘤免疫效应。     

腺病毒介导CTLA4Ig基因修饰的骨髓基质细胞诱导特异性免疫耐受的实验研究

目的　通过腺病毒介导CTLA4Ig在骨髓基质细胞 (bonemarrowstromalcells ,BMSCs)中的表达 ,探讨CTLA4Ig体外诱导特异性免疫耐受的机制 ,为该基因修饰的BMSCs联合造血干细胞移植 (hematopoieticstemcelltransplantation ,HSCT) ,达到预防移植物抗宿主病 (graft versus hostdisease ,GVHD)和纠正预处理损伤的造血微环境 (hematopoieticinductivemicroenvironment,HIM)积累实验依据。方法　以CTLA4Ig 重组腺病毒按感染复数 (mutiplicityofinfection ,MOI) 5 0转染BMSCs,利用亲和层析的方法纯化培养上清中的目的蛋白CTLA4Ig ,加入到混合淋巴细胞反应 (mixedlymphocytereaction ,MLR)体系中 ,通过MTT显色观察其抑制淋巴细胞增殖的生物学效应 ,以ELISA检测体系中IL 2的水平。结果　纯化的CTLA4Ig对MLR反应体系中淋巴细胞的增殖有明显的抑制作用 ,且在一定范围内与CTLA4Ig的浓度呈依赖性关系 ;体系中IL 2水平与淋巴细胞数有相似的变化趋势 ,且成正相关 (γ =0 85 2 2 ) ;CTLA4Ig组的淋巴细胞数与IL 2水平与对照组相差显著 (P <0 0 5 )。结论　转染后BMSCs表达的目的蛋白CTLA4Ig能有效阻断B7/CD2 8共刺激信号途径 ,从而抑制T细胞活化 ,抑制IL 2的产生     

共刺激分子B7.1和葡萄球菌肠毒素A膜表面共修饰瘤苗抗肿瘤作用的研究

目的 观察跨膜型葡萄球菌肠毒素A(SEA-TM)和糖基化磷脂酰肌醇锚定型mB7．1(mB7．1-GPI)二种免疫分子膜表面修饰瘤苗的抗肿瘤作用是否优于单种免疫分子膜表面修饰的瘤苗。方法构建pcDNA3．1( )／mB7．1-GPI真核表达载体,转染中国仓鼠卵巢上皮细胞(CHO)中,表达和纯化mB7．1-GPI。通过蛋白转染法将SEA-TM、mB7．1-GPI单独或共同锚定到EL-4肿瘤细胞膜上,制成瘤苗,观察这些瘤苗刺激小鼠脾细胞的增殖和分泌白细胞介素(IL)-2和γ干扰素(IFN)-γ的量及抗肿瘤作用。结果mB7．1-GPI。和SEA-TM能单独或共同锚定在肿瘤细胞膜上,具有相当的稳定性;在体外有刺激小鼠脾细胞增殖和分泌IL-2、IFN-γ的功能。mB7．1-GPI、SEA-TM、mB7,1-GPI SEA-TM锚定肿瘤细胞,制成的瘤苗,能抑制荷瘤小鼠的肿瘤生长和延长荷瘤小鼠的存活时间。mB7．1-GPI和SEA-TM双锚定瘤苗,显示出比单一蛋白锚定瘤苗更强的抗肿瘤作用。结论用蛋白转染法将SEA和mB7.1二种免疫分子同时锚定到肿瘤细胞膜上所制成的瘤苗,其抗肿瘤作用优于单种免疫分子锚定的瘤苗。     

Silencing the expression of Cbl-b enhances the immune activation of T lymphocytes against RM-1 prostate cancer cells in vitro

BackgroundThe ubiquitin ligase Cbl-b potently modulates T lymphocyte immune responses and is critical in modulating tumor-induced immunosuppression. The influence of Cbl-b in modulating T lymphocyte activity against prostate cancer remains ill defined. We have determined the effects of silencing Cbl-b expression in T lymphocytes and their subsequent cytotoxic activity against prostate cancer cells.MethodsT lymphocytes were isolated from the spleens of C57BL/6 mice. Lipofectamine-directed transfection of T lymphocytes with specific small interfering RNA (siRNA) silenced Cbl-b expression, which was confirmed by Western immunoblotting. The siRNA species were chosen that promoted the greatest transfection efficiency and dampened Cbl-b expression in T lymphocytes. The expression of CD69, CD25, and CD71 by the transfected T lymphocytes was determined by flow cytometry. T lymphocyte proliferation was assessed by CCK-8 assay. Enzyme-linked immunosorbent assay (ELISA) was used to measure the secretion of interleukin (IL)-2, interferon (IFN)-γ, and tumor necrosis factor (TNF)-β. The objective was to compare the cytotoxic activity of transfected T lymphocytes and nontransfected (i.e., negative control) T lymphocytes against the murine prostate cancer cell line target RM-1 in vitro.ResultsWe selected a specific siRNA that decreased T lymphocyte Cbl-b expression to 15%. The siRNA-transfected T lymphocytes showed higher proliferation; higher CD69, CD25, and CD71 expression (p < 0.001); and higher IL-2, IFN-γ, and TNF-β secretion (p < 0.05), compared to the nontransfected cells. Transfected T lymphocytes were also more potent at killing RM-1 prostate cancer cells, compared to the negative control in vitro.ConclusionSilencing Cbl-b significantly enhanced T lymphocyte function and T lymphocyte cytotoxicity activity against a model prostate cancer cell line in vitro. This study suggests a potentially novel immunotherapeutic strategy against prostate cancer.     

CTLA4Ig基因转染猪皮异种移植的体外实验研究

目的 探索重组腺病毒载体（Recombinant adenovirus,rAdv）介导CTLA4Ig基因转染猪皮异种移植免疫耐受的分子机制。方法 构建CTLA4Ig重组腺病毒载体,转染猪树突状细胞（Dendritic Cell,DC）,以猪表皮细胞匀浆液为刺激原,观察DC递呈猪表皮抗原刺激人T细胞增殖、活化及信号转导的影响;同时,以CTLA4Ig转染小鼠DC细胞,观察该DC膜表面分子CD40、CD80表达。结果 CTLA4Ig转染DC能显著抑制人外周血T淋巴细胞增殖能力（P＜0.01）和T细胞肌醇磷脂信号系统转导活性,IL－2分泌亦受到明显抑制（P＜0.05）;转染CTLA4Ig的小鼠DC膜表面分子CD80表达降低（P＜0.05）。结论 腺病毒介导CTLA4Ig基因转染转皮能诱导人外周血T淋巴细胞免疫耐受。     

土槿乙酸C-18醇酯衍生物的合成及其体外免疫抑制活性研究

目的:将土瑾乙酸C-18位进行结构改造,筛选出具有高效、低毒、水溶性好等优点的新型免疫抑制化合物。方法:将C-18 位还原为醇羟基,通过缩合酰化反应引入苯环、呋喃环、吡啶环羧酸,得到土槿乙酸C-18醇酯衍生物。经 MTT 法对小鼠 T、B 淋巴细胞的免疫抑制活性和对小鼠正常脾细胞毒性体外细胞实验筛选。结果:合成得到10个未见文献报道的土瑾乙酸C-18醇酯衍生物B1-B10,所合成的目标化合物均经1H-NMR, 13C-NMR, HR-ESI进行结构确定,并测定了其体外免疫抑制活性,结果显示其中衍生物B2、B6、B7对 T 淋巴细胞增殖抑制活性强于土槿乙酸, 衍生物B6、B7 对 B 淋巴细胞抑制活性明显强于土槿乙酸。尤其是大多数化合物对正常细胞作用很弱,远低于阳性对照药,呈现高效低毒特性。结论:土槿乙酸C-18醇酯衍生物,引入呋喃环,抑制 T、B 淋巴细胞增殖活性明显增加,引入具有共轭体系的呋喃环时活性更佳,并且毒性降低。     

In Vitro Anti-tumor Immune Response Induced by Dendritic Cells Transfected with Recombinant Adenovirus Carrying Mutant K-ras Genes

Summary： The specific anti-tumor immune response induced by mouse bone marrow dendritic cells （DCs） lransfected with recombinant adenovirus carrying mutant k-ras genes was investighted. DCs were generated from mouse bone marrow in the presence of rmGM-CSF （3.3 ng/mL） and rmIL-4 （1.3 ng/mL） and detected by FACS, and then transfecled with the recombinant adenovirus encoding mutant k ras gene. The efficacy of transfection and T cell stimulating activity of DCs were detected. CTL activity of the mice vaccinated with DCs was observed. The resuhs showed thai DCs had dendritic veiled morphology. BmDCs highly expressed B7-1（80%）, B7-2（77%）, MHC Ⅱ （70%）, CDllc （65%）, CD40 （70%） and CD54 （96%） with FACS, and no significant difference in the expression was observed before and after the transfection （P〈0.05）. The DCs transfeeled by mutant k-ras gene could significantly stimulate lymphoeytes proliferation as compared with those transfeeted by Ad e or non-modified DCs （P〈0.05）. DC vaccine transfected by mutant k-ras gene could induce CTL activity against Lewis lung cancer, but not against B16. The specific eytotoxicity against Lewis lung cancer in Ad-k-ras/12-transdueed DC group was signifieantly higher than those in the control, vector and non transfeeted DCs groups （P〈0.05）. It was concluded that special antitumor response could be induced by DCs transfected with recombinant adenovirus carrying mutant k-ras genes.     

转B7-1基因的人多发性骨髓瘤细胞XG-7在激发杀肿瘤细胞CTL中的作用

为调查B7－1分子在人多发性骨髓瘤细胞的表达是否可诱导出具有抗肿瘤作用的CD8 的CTL，我们用含B7－1基因逆转录病毒载体PTG5192的包装细胞293E的培养上清，感染人多发性骨髓瘤细胞系XG－7（不表达B7－1分子），用新霉素G418选择并经流式细胞仪筛选，获得了稳定高表达B7－1分子的XG－7细胞（命名为XG－7－B7细胞）。在体外增殖实验中，XG－7－B7细胞显示出比母系细胞XG-7对外周血淋巴细胞（PBL）具有更大的刺激活性。表型分析证实XG-7-B7细胞所刺激的PBL是一群T细胞，其表型特征为CD3，CD8阳性，CD25、CD28也高表达，而CD4和CD16几乎不表达。这群细胞可在体外长期培养扩增，并可用作效应细胞。细胞毒实验结果表明：CD8 T细胞可杀死XG－7－B7细胞、母系细胞XG－7和其它肿瘤细胞如K562与Daudi细胞。结果提示，这群肿瘤持异的CD8 CTL细胞对肿瘤的过继免疫治疗具有潜在的应用价值。     

中西医结合治疗膀胱肿瘤的基础研究

目的：探讨转基因肿瘤疫苗与大蒜素联合治疗膀胱肿瘤的效果与机理.方法：脂质体转染法将B7.1基因导入鼠膀胱肿瘤（MBT-2）细胞.免疫荧光染色测定B7.1分子的表达.混合淋巴细胞培养MTT法和LDH释放法观察对免疫系统的影响.MTT法测定大蒜素对肿瘤细胞生长的影响.动物实验测定联合治疗效果.结果：B7.1转基因肿瘤疫苗能有效刺激淋巴细胞增殖.与大蒜素能产生协同抗癌效果.这种协同抗癌效果与淋巴细胞的特异性杀伤活性有关.结论：转基因肿瘤疫苗与大蒜素合用有更好的抗肿瘤效果.     

HSA基因转染小鼠EL-4淋巴瘤细胞以提高其免疫原性的研究

目的探讨ＨＳＡ提供的协同刺激信号能否增强肿瘤细胞的免疫原性。方法将ＨＳＡｃＤＮＡ导入小鼠淋巴瘤细胞ＥＬ－４中,通过含Ｇ４１８的ＲＰＭＩ１６４０培养基将表达ＨＳＡ分子的ＥＬ－４细胞（ＨＳＡ＋ＥＬ－４）筛选出来。用混合淋巴细胞肿瘤细胞培养（ＭＬＴＣ）的方法观察ＨＳＡ＋ＥＬ－４细胞免疫小鼠脾细胞的增殖应答反应和ＣＴＬ杀伤活性。Ｃ５７ＢＬ／６小鼠接种野生型ＥＬ－４细胞后７ｄ,给予灭活的ＨＳＡ＋ＥＬ－４细胞瘤苗或联合低剂量ＩＬ－２治疗,观察荷瘤小鼠皮下肿瘤生长及存活期情况。结果ＨＳＡ＋ＥＬ－４细胞免疫小鼠的细胞对ＨＳＡ＋ＥＬ－４或ＥＬ－４瘤细胞刺激增殖反应及对亲本瘤细胞ＥＬ－４的杀瘤活性明显高于ＥＬ－４ｖ细胞（空载体转染的ＥＬ－４细胞）免疫小鼠脾细胞的。ＨＳＡ＋ＥＬ－４细胞作为瘤苗,早期治疗荷瘤小鼠,可延缓肿瘤的生长,延长荷瘤小鼠的存活期,尤其与低剂量ＩＬ－２联合应用时治疗效果更好。结论协同刺激分子ＨＳＡ在肿瘤细胞上的表达可增强瘤细胞的免疫原性;表达ＨＳＡ分子的肿瘤细胞可在小鼠体内诱导出有效的抗肿瘤免疫应答反应。