人PSCA真核表达质粒的构建及稳定转染B16细胞系的建立

目的:构建真核表达质粒pcDNA3.1-PSCA,通过稳定转染建立高效表达人前列腺干细胞抗原(PSCA)的小鼠黑色素瘤B16细胞系。方法:利用PCR扩增出人PSCA全长基因的cDNA编码区序列,使用基因重组技术将其克隆到真核表达载体pcDNA3.1中,得到重组表达质粒pcDNA3.1-PSCA。双酶切及测序鉴定后,利用脂质体法将其转染入小鼠黑色素瘤B16细胞,G418加压筛选后得到阳性克隆。通过流式细胞术、免疫荧光及Western blot检测PSCA在细胞系中的表达情况。结果:经测序及双酶切鉴定,pcDNA3.1-PSCA重组质粒构建正确;稳定转染人PSCA的B16细胞系表达率接近100%。结论:建立的稳定转染人PSCA的B16细胞系能够高效表达PSCA基因,为抗前列腺癌疫苗的功能研究奠定了基础。     

人hCGβ真核表达载体的构建及稳定转染B16细胞系的建立

目的:构建人hCGβ真核表达载体,稳定转染入小鼠黑色素瘤B16细胞,建立稳定表达人hCGβ的小鼠黑色素瘤细胞系。方法:采用PCR方法扩增出人hCGβ全长基因的cDNA编码区序列,利用DNA重组技术将其定向插入到真核表达载体pIRES-neo中,并加入酶切位点和6×His标签,得到重组表达质粒pIRES-neo-hCGβ-(His)6。利用阳离子脂质体介导法将其稳定转染入小鼠黑色素瘤B16细胞,经G418加压筛选出阳性克隆。RT-PCR、Westernblot及免疫荧光检测人hCGβ在B16细胞中的表达。结果:经限制性内切酶鉴定及序列分析,pIRES-neo-hCGβ-(His)6重组体构建正确,最终建立的表达人hCGβ基因的B16细胞系阳性率高于90%。结论:成功构建了真核表达载体pIRES-neo-hCGβ-(His)6,建立的稳定转染人hCGβ小鼠黑色素瘤细胞系能够高效表达hCGβ基因。该稳定转染细胞系的建立为进一步研究人hCGβ抗肿瘤基因疫苗的功能提供了良好的实验基础,为hCGβ在肿瘤免疫治疗中的应用奠定了研究基础。     

人DRR1真核表达载体和稳定转染HEK293细胞株的建立及鉴定

目的:构建人DRR1基因的真核表达载体,通过转染HEK293细胞建立稳定的DRR1表达细胞株.方法:通过改造质粒pIRES,在其MCS1和MCS2中分别引入串联亲和纯化标签和绿色荧光蛋白基因,形成一个新的表达质粒pFSIG.将PCR扩增的DRRl1基因插入pFSIG中进行酶切和测序验证.用重组质粒pFSIG-DRR1转染HEK293细胞,通过G418和绿色荧光检测筛选DRR1稳定表达细胞株.通过Westernblot鉴定FS-DRR1蛋白的表达.结果:酶切、PCR和测序证实成功构建了pFSIG-DRR1表达质粒;建立了稳定转染的HEK293细胞系,Western blot检测证明重组DRR1在该细胞系中成功表达.结论:融合有串联亲和纯化标签的DRR1真核表达载体的构建和稳定表达细胞HEK293株的建立为在生理条件下研究DRR1的相互作用蛋白奠定了基础.     

稳定表达人乳头瘤病毒(HPV)58型E6E7融合基因的B16细胞系的建立

目的:构建pIRES-neo-HPV58E6E7真核表达载体,稳定转染入小鼠黑色素瘤B16细胞,建立稳定表达HPV58E6E7基因的B16细胞系。方法:采用PCR方法扩增出HPV58E6E7融合基因的全长序列,利用DNA重组技术将其定向插入到真核表达载体pIRES-neo中,并加入酶切位点和6×his标签,构建重组真核表达质粒pIRES-neo-HPV58E6E7。利用阳离子脂质体介导法将其转染入小鼠黑色素瘤B16细胞,经G418加压筛选出稳定转染的阳性克隆。利用Western blot、流式细胞术、免疫荧光等检测方法验证HPV58E6E7融合基因在稳定转染的B16细胞株中的表达。结果:经PCR、限制性内切酶鉴定及测序分析,pIRES-neo-HPV58E6E7重组质粒构建正确,转染B16细胞株后,经过Western blot、流式细胞术和免疫荧光等检测显示B16细胞株能够稳定、高效表达HPV58E6E7融合基因,表明B16-HPV58E6E7稳定转染细胞系构建成功。结论:成功构建了pIRES-neo-HPV58E6E7真核表达载体,建立了可以高效、稳定表达HPV58E6E7融合基因的B16细胞系。该稳定转染细胞系的建立为进一步研究HPV58治疗性基因疫苗的功能提供了良好的靶细胞,为其在肿瘤免疫治疗中的应用奠定了研究基础。     

配对盒基因6/小鼠胚胎干细胞细胞系的建立及干细胞生物学特性分析

目的 建立配对盒基因6（Pax6）/小鼠胚胎干细胞（mESCs）细胞系并鉴定其干细胞生物学特性。 方法 体外培养mESCs,将重组载体pEF1α-Pax6-IRES-AcGFP和空载体pEF1α-IRES-AcGFP分别用脂质体法转染mESCs,经G418梯度及荧光蛋白双筛选后,使用细胞免疫荧光染色、免疫印迹法及RT-PCR技术检测Pax6的表达情况,流式细胞术检测Pax6/mESCs阳性细胞的比例。将获得正确的细胞系分别采用细胞免疫荧光染色对其干细胞标志物阶段特异性胚胎抗原1（SSEA1）、八聚体结合转录因子4（OCT4）进行检测,碱性磷酸酶（AP）染色法对其多能性进行检测,流式细胞术检测增殖指数Ki67。将Pax6/mESCs进行肾背囊下移植,移植物行HE染色观察其分化能力。 结果 Pax6成功在mESCs内表达,经G418筛选后,获得Pax6/mESCs细胞系,流式结果显示,Pax6阳性率为90%,免疫荧光显示,干细胞标志物SSEA1、OCT4表达阳性且AP染色阳性,并且在体内移植后能向3个胚层分化。 结论 Pax6成功在mESCs内表达,经G418筛选后,获得细胞系Pax6/mESCs并维持良好的干细胞特性。     

Up-regulation of human epidermal Langerhans' cell B7-1 and B7-2 co-stimulatory molecules in vivo by solar-simulating irradiation

Ultraviolet (UV) radiation impairs cutaneous immune functions and induces antigen-specific tolerance both locally at the irradiated skin site, as well as at distant skin sites and systemically. It has been postulated that in the local model, altered Langerhans' cells (LC) provide tolerogenic signals, and studies in vitro have indicated that UV radiation may down-regulate the expression of co-stimulatory molecules on the surface of these cells. To examine the effect of UV radiation on LC co-stimulatory molecules in vivo, we irradiated human volunteers with erythematogenic doses of solar-simulating UV radiation (SSR), and analyzed the expression of cell surface markers in dermatome skin samples obtained 1–72 h post-irradiation. For flow cytometric analysis, epidermal cell (EC) suspensions were prepared and double labeled with monoclonal antibodies against CD1a or HLA-DR, and B7-1 (CD80), B7-2 (CD86), ICAM-1 (CD54), ICAM-3 (CD50), LFA-3 (CD58), E-cadherin, or integrin-β₄ (CD104). In unirradiated control skin samples, keratinocytes (KC) expressed high levels of E-cadherin. LC expressed high levels of both E-cadherin and ICAM-3, and low levels of B7-2, LFA-3, ICAM-1, and integrin-β₄. Following SSR, a triphasic reaction pattern was seen: an immediate, down-regulatory phase prevailing 2–6 h post-irradiation, when the number of DR⁺ and CD1a⁺ cells were temporarily reduced; a delayed, up-regulatory phase in which the number of LC was increased and the expression intensities of CD1a, HLA-DR, B7-1, and B7-2 were strongly up-regulated, maximally evident 12–24 h after irradiation, but no more seen at 48 h; and a late phase at 72 h, in which an influx of monocytes and a concomitant rise in DR⁺ cells was recorded. We conclude that to understand real-life cutaneous UV immunology, studies in vitro need to be complemented with studies in vivo. In the case of LC, the effects of erythematogenic UV radiation in vivo on human LC B7 co-stimulatory molecules include an up-regulatory stage.     

体内稳定表达HER2多表位基因B16细胞系的建立

目的:建立体内稳定表达HER2多表位基因的小鼠黑色素瘤B16细胞系.方法:利用分子克隆技术构建真核表达载体peDNA3-GFP-HEK2,阳离子脂质体介导法将其稳定转染入B16细胞,G418克隆筛选及体内传代后,流式细胞术(FCM)分选出GFP-HER2表达阳性细胞群,对该群细胞进行无G418条件下的单克隆筛选并进行体内稳定性检测.结果:经限制性内切酶鉴定及序列分析,peDNA3-GFP-HER2构建正确;最终建立的表达HER2基因B16细胞系体内传代后GFPHER2阳性率高于90%.结论:成功建立了体内稳定表达HER2多表位基因的小鼠黑色素瘤细胞系,为其他体内稳定表达外源基因的转染细胞的建立提供了借鉴.     

GAM cDNA稳定转染的M1细胞系的建立与鉴定

目的为搞清 GAM在 gp130介导的信号传导中所起的作用。方法选择在 IL - 6刺激下出现分化和增殖抑制的M1细胞系 ,分别用正向和反向插入 GAM c DNA的真核表达载体 p EF- BOS与 p SV2 - neo质粒共转染 ,经 G418选择培养筛选得到稳定转染的细胞 ,并用半套式 PCR方法证实了 GAM基因与这两种细胞基因组 DNA的整合。结果流式细胞仪分析表明正向 GAM c DNA转染的 M1细胞中 GAM的表达水平明显升高 ,3H掺入实验表明 GAM表达水平升高使 M1细胞对 IL - 6的反应性下降。结论 GAM高表达 M1细胞的建立为深入研究 GAM在 gp130介导的信号传导中的作用提供了良好的实验模型     

表达特定免疫球蛋白可变区抗原的人B细胞系建立和其生物学特征

目的建立表达特定免疫球蛋白可变区抗原的人B细胞系。方法在29例EBV转化B淋巴细胞建立永生化淋巴母细胞系中,PCR-SSP方法检测HLA-A*0201表达的细胞系,将表达HLA-A*0201的细胞系通过有限稀释培养方法获得单克隆细胞系ZP-1。分别用PCR方法、流式细胞仪和染色体核型分析检测细胞IgHV家族、细胞表面免疫表型CD分子和染色体核型表达。结果 HLA-A*0201(+)的细胞,经单克隆化培养后获得3个细胞克隆,将其中之一命名为ZP-1。PCR检测显示ZP-1细胞表达IgHV3家族;流式细胞仪检测显示ZP-1细胞表达CD19、lambda链等B细胞免疫表型;核型分析结果显示,ZP-1细胞为正常女性染色体结构。结论成功获得表达特定免疫球蛋白可变区抗原的人B细胞系,为研发B细胞相关疾病的疫苗和分子靶向药物提供良好的实验基础。     

瘤源性IDO2对黑色素瘤形成及生长的影响

目的研究B16-BL6细胞内IDO2基因表达对小鼠黑色素瘤生长、发展及抗肿瘤免疫的影响。方法通过G418药物筛选建立稳定细胞系B16-BL6/IDO2^+及B16-BL6/IDO2^+,q PCR法检测IDO2的表达,MTT实验检测IDO2表达对细胞增殖的影响;然后以构建的稳定细胞在小鼠体内建立肿瘤模型,观察IDO2表达对黑色素瘤形成、生长的影响;最后在处死小鼠后通过流式细胞术检测引流淋巴结内Treg、CD4^+/CD8^+T细胞百分比及T淋巴细胞凋亡率,LDH法检测肿瘤特异性细胞毒反应来观察肿瘤组织内IDO2表达对引流淋巴结内肿瘤免疫的影响。结果成功建立B16-BL6/IDO2^+及B16-BL6/IDO2^-稳定细胞系:B16-BL6/IDO2^-细胞持续稳定低表达IDO2且不受LPS及IFN-γ的诱导;与B16-BL6/IDO2^+细胞相比,B16-BL6/IDO2^-细胞在体外增殖速度减慢,体内实验显示其肿瘤生长速度减慢、肿瘤质量减轻;进一步流式细胞术结果发现:引流淋巴结内Treg百分比下降、CD8^+T细胞数量增加、T淋巴细胞的凋亡率减少;LDH法检测CD8^+细胞特异性特异性杀伤肿瘤细胞反应增强。结论黑色素瘤细胞内IDO2的表达参与体内肿瘤的生长过程,且能影响其引流淋巴结内肿瘤免疫反应。     

Engineering in vivo gradients of sphingosine-1-phosphate receptor ligands for localized microvascular remodeling and inflammatory cell positioning

Biomaterial-mediated controlled release of soluble signaling molecules is a tissue engineering approach to spatially control processes of inflammation, microvascular remodeling and host cell recruitment, and to generate biochemical gradients in vivo. Lipid mediators, such as sphingosine 1-phosphate (S1P), are recognized for their essential roles in spatial guidance, signaling and highly regulated endogenous gradients. S1P and pharmacological analogs such as FTY720 are therapeutically attractive targets for their critical roles in the trafficking of cells between blood and tissue spaces, both physiologically and pathophysiologically. However, the interaction of locally delivered sphingolipids with the complex metabolic networks controlling the flux of lipid species in inflamed tissue has yet to be elucidated. In this study, complementary in vitro and in vivo approaches are investigated to identify relationships between polymer composition, drug release kinetics, S1P metabolic activity, signaling gradients and spatial positioning of circulating cells around poly(lactic-co-glycolic acid) biomaterials. Results demonstrate that biomaterial-based gradients of S1P are short-lived in the tissue due to degradation by S1P lyase, an enzyme that irreversibly degrades intracellular S1P. On the other hand, in vivo gradients of the more stable compound, FTY720, enhance microvascular remodeling by selectively recruiting an anti-inflammatory subset of monocytes (S1P₃^high) to the biomaterial. Results highlight the need to better understand the endogenous balance of lipid import/export machinery and lipid kinase/phosphatase activity in order to design biomaterial products that spatially control the innate immune environment to maximize regenerative potential.     

转染小鼠CXCR3基因的B16-mCXCR3细胞在体内外迁移和致瘤作用研究

目的:建立稳定表达小鼠CXCR3基因的B16细胞株,研究CXCR3分子在肿瘤形成及转移过程中的作用。方法:采用PCR方法从pMD19-T/mCXCR3质粒中扩增CXCR3基因,插入到真核表达载体pIRES2-EGFP中,脂质体法转染小鼠黑色素瘤细胞B16;G418加压筛选阳性克隆,分别用RT-PCR方法与免疫荧光技术分析阳性克隆中CXCR3在mRNA和蛋白水平的表达。采用Transwell系统检测B16-mCXCR3细胞在其配体IP-10介导下的迁移能力。将B16-mCXCR3细胞分别通过皮下和眼静脉注射接种于BALB/c小鼠,观察在小鼠体内的成瘤率及肿瘤转移情况。结果:构建了表达小鼠CXCR3基因的真核表达载体pIRES2-EGFP/mCXCR3,转染该载体后获得了稳定表达CXCR3的B16-mCXCR3细胞。B16-mCXCR3细胞(1×105个),在20μg/L IP-10作用下迁移的细胞数为3 208个,与B16组和B16-mock组相比均具有统计学意义(P<0.01)。于小鼠皮下接种B16-mCXCR3细胞、B16细胞和B16-mock细胞,第20天成瘤率均为100%。于小鼠眼静脉注射B16-mCXCR3细胞,第21天时50%的小鼠在肺部出现肉眼可见的黑色肿瘤转移灶,B16细胞组和B16-mock细胞组肺部未见肿瘤转移灶,B16-mCXCR3组与B16组和B16-mock组相比均具有统计学意义(P<0.01)。结论:转染CXCR3基因的B16-mCXCR3细胞,在IP-10介导下可定向迁移,并可增加在小鼠体内的转移率。