MAGE-1与人HSP70融合基因真核表达载体的构建及在小鼠黑色素瘤细胞内的表达

目的:构建MAGE-1(melanomaantigen1)与人HSP70(heatshockprotein70)融合基因的真核表达载体PIRES2-EGFP-MAGE-1-HSP70,并观察在小鼠黑色素瘤细胞内的表达,为肿瘤DNA疫苗研究奠定基础。方法:HSP70基因经酶切后连入真核表达载体PIRES2-EGFP,再通过PCR方法扩增MAGE-1基因,测序后插入PIRES2-EGFP-HSP70中HSP70基因的5'端,构建了MAGE-1与人HSP70融合基因表达载体PIRES2-EGFP-MAGE-1-HSP70。结果:扩增了MAGE-1基因,测序结果表明与GenBank公布的序列一致,成功地构建了PIRES2-EGFP-MAGE-1-HSP70真核表达载体。结论:成功地构建MAGE-1与人HSP70融合基因的真核表达载体PIRES2-EGFP-MAGE-1-HSP70,并在小鼠黑色素瘤细胞系稳定表达,为进一步DNA肿瘤疫苗研究提供了实验基础。     

睾丸肿瘤抗原MAGE-C2基因cDNA的克隆、表达与纯化

目的　克隆人睾丸肿瘤抗原MAGE- C2基因的c DNA,并在大肠杆菌中进行表达与纯化,以便为研究其生物学功能及制备肿瘤疫苗奠定基础。方法　从人胶质瘤细胞系BT- 32 5中提取总RNA,用RT- PCR从中扩增出MAGE- C2的c DNA片段,将MAGE- C2的c DNA片段插入载体p GEM- T easy中,经全自动序列分析仪测序正确后,再克隆至表达载体p GEX- 4 T- 2中,构建重组表达载体p GEX- 4 T- 2 - MAGE- C2 ,并转化大肠杆菌,用IPTG进行诱导后,收集细菌,菌体裂解后,利用GST亲和层析柱对表达蛋白进行纯化,并进行SDS- PAGE及Western- blot检测。结果　从人胶质瘤细胞系BT- 32 5中克隆到长4 0 0 bp的MAGE- C2的c DNA,测序正确;经Xho I和Bam H I酶切鉴定证实,MAGE- C2 c DNA成功克隆到表达载体p GEX- 4 T- 2中;构建的表达载体p GEX- 4 T- 2 - MAGE- C2在大肠杆菌中表达出Mr4 10 0 0的融合蛋白,经谷胱甘肽(GST)亲和层析后的融合蛋白纯度达到90 % ,该融合蛋白具有MAGE- C2抗原特性。结论　成功地克隆并表达了MAGE- C2 c DNA,并对融合蛋白进行了初步纯化,为大规模获得MAGE- C2抗原创造了条件。     

异种EGFR胞外区重组DNA疫苗与蛋白质疫苗抗小鼠Lewis肺癌的作用研究

目的:构建异种表皮生长因子受体(epidermal growth factor receptor,EGFR)胞外区重组DNA和蛋白质疫苗,观察其对小鼠Lewis肺癌的抗肿瘤作用.方法:克隆鸡源性EGFR胞外Ⅱ-Ⅲ区与IgG-Fc融合基因,构建重组DNA疫苗质粒pVAX1-cEGFR-Fc和原核表达质粒pET28a(+)-S-cEGFR-Fc,后者转化大肠杆菌,将诱导表达的重组蛋白作为蛋白质疫苗.免疫小鼠4次后接种Lewis肺癌细胞,19 d后处死小鼠,剥离肿瘤称重并计算抑瘤率,检测小鼠血清中抗EGFR抗体效价,并检测特异性细胞毒性T淋巴细胞( cytotoxicity T lymphocyte,CTL)活性.结果:成功构建异种EGFR胞外区重组DNA和蛋白质疫苗.DNA疫苗组、蛋白质疫苗组和联合免疫组的抑瘤率分别为37%、49%和63%.3组小鼠均检测出抗EGFR抗体和CTL反应.结论:重组疫苗能打破机体对自身EGFR分子的免疫耐受,诱导特异性免疫反应,对小鼠Lewis肺癌有明显的抑制作用.2种疫苗的联合应用可进一步加强抑瘤作用.     

基因枪介导的neu基因DNA疫苗抗肿瘤作用的实验研究

目的 探讨DNA疫苗pWRG-neu的皮内免疫,对高表达neu基因的小鼠移植瘤生长和转移的抑制作用。方法 向小鼠黑色素瘤B16F10细胞系转染pcDNA-neu,用有限稀释法筛选一株高表达neu基因的细胞株B16F10-neu。在基因枪介导下,向C57BL／6小鼠导入DNA疫苗pWRG-neu,通过观察免疫动物的生存期,评价DNA疫苗的抗肿瘤作用。分离免疫动物脾细胞,经自体淋巴细胞混合培养实验,分析DNA疫苗体内免疫后机体的CTL应答。结果 筛选到一株高表达neu基因的B16F10-neu细胞株,转基因过程和外源基因的表达没有改变细胞系的增殖特性。用基因枪轰击,进行DNA疫苗pWRG-neu皮内免疫,对小鼠黑色素瘤B16F10-neu进行预防、治疗和抗转移的实验研究,结果表明,DNA疫苗的免疫能够明显推迟移植瘤的生长,延长小鼠生存期,获得明显的抗肿瘤效果。DNA疫苗免疫后可诱导小鼠脾淋巴细胞CTL活性。结论 基因枪介导的DNA疫苗pWRG-neu经皮内免疫,能够有效的诱导机体的细胞免疫应答,预防和治疗小鼠移植瘤的发生,并有一定的预防肿瘤肺转移的作用。     

MAGE-3 原核重组表达载体的构建和表达

 目的 构建原核重组表达载体pGEX-4T-1-MAGE-3并检测其在大肠杆菌（E.coli）BL21中的表达。方法 RT-PCR法制备MAGE-3目的基因,采用DNA重组技术将其克隆至pGEM-TEasy和亚克隆至pGEX-4T-1载体,转化E.coliBL21株,经IPTG诱导,12%SDS-PAGE电泳分离和Western Blot表达鉴定。结果 扩增出349bp的MAGE-3目的基因并构建了原核重组表达载体pGEX-4T-1-MAGE-3;测序结果与Gen Bank收录序列相一致;在E.coli BL21中检测到含该重组表达载体的转化菌表达出分子量约35kD的融合蛋白并证实其为目的蛋白。结论 成功构建的原核重组表达载体pGEX-4T-1-MAGE-3及其所表达的融合蛋白,为以MAGE-3为基础的肽疫苗及特异诊断试剂的研制提供抗原打下了基础,为后续实验提供了依据。     

人生存素基因的克隆、表达与抗血清制备

目的克隆表达重组人生存素,制备其抗血清并检测其免疫识别活性。方法用RT-PCR方法从培养的人白血病细胞株HL-60中克隆人生存素cDNA,克隆到原核表达载体pET32a(+),重组质粒转化大肠杆菌BL21(DE3)进行表达,目的蛋白经Ni-NTA树脂亲和纯化后免疫小鼠制备抗血清,ELISA检测抗血清的效价,Western blot和免疫细胞化学法鉴定抗血清的特异性。结果所克隆生存素cDNA序列与Genbank中序列完全一致,将其读码框插入原核表达载体pET32a(+)诱导表达后,SDS-PAGE电泳分析证实重组蛋白为分子量约37KD的融合蛋白,表达量占总菌体的30%,纯化后融合蛋白的纯度为95%,所制备的鼠抗血清的效价达1:1600,Western blotting证实其有较好的特异性,可以检测肿瘤细胞生存素的表达。结论我们已克隆并表达了人生存素基因,所制备的抗人生存素血清可用于相关肿瘤检测。     

ULBP3胞外段基因的克隆与表达

目的 为了研究ULBP3刺激NK细胞增殖分化的功能，首先需构建、表达ULBP3胞外段重组蛋白。方法 用RT-PCR方法从人结肠癌组织中钓取ULBP3胞外段基因，构建pET32a原核表达载体，转化大肠杆菌BL21，以IPTG诱导表达，Western blot鉴定。结果 经测序证实，所获得的cDNA克隆为ULBP3胞外段基因，其序列与genebank中已经发表的序列完全一致，pET32a原核表达载体转化大肠杆菌BL21后，经筛选获得的阳性重组菌稳定表达ULBP3胞外段重组蛋白。结论 成功表达了ULBP3胞外段重组蛋白，可用于进一步研究ULBP3刺激NK细胞增殖分化的功能。     

人MAGE-3真核表达载体的构建与表达

目的 克隆人黑色素瘤特异性抗原MAGE-3基因，构建真核表达载体，建立MAGE-3阳性细胞株，制备肿瘤核酸疫苗。方法 用RT—PCR方法扩增MAGE-3cDNA，以pcDNA3．1 为载体，构建重组表达质粒pcDNA3．1／MAGE-3。重组质粒用脂质体转染鼠B16细胞，经RT—PCR、细胞免疫染色及免疫印迹法鉴定转化细胞中MAGE-3的表达。结果 正确构建了pcDNA3．1／MAGE-3重组质粒，并且在转化细胞中检测到了MAGE-3的表达。结论 成功构建了pcDNA3．1／MAGE-3真核表达质粒，建立了稳定表达人MAGE-3的鼠B16细胞株。     

cEGFR-rFc融合DNA疫苗抗小鼠黑素移植瘤的效果

目的:构建cEGFR-rFc融合DNA疫苗, 观察其对小鼠黑素移植瘤的抑制作用.方法:以异种同源鸡EGFR(chicken EGFR,cEGFR)膜外部分与兔疫球蛋白IgG的Fc段(rabbit IgG Fc,rFc)为基础构建真核表达载体pVAX1/cEGFR-rFc,脂质体法转染黑素瘤B16 细胞,免疫荧光法检测融合蛋白在B16细胞中的表达;以融合DNA疫苗免疫C57BL/6J小鼠,Western blotting法检测融合蛋白在小鼠体内的稳定表达.疫苗免疫小鼠接种B16黑素瘤细胞,14 d后处死部分小鼠,取出瘤体称重,计算抑瘤率;同时观察小鼠荷瘤后的生存率;ELASIA法检测DNA疫苗免疫小鼠血清抗EGFR抗体滴度,流式细胞仪测定小鼠脾细胞淋巴细胞亚群.结果:成功构建融合DNA疫苗pVAX1/ cEGFR-rFc,重组载体转染B16细胞后能检测到融合蛋白显著表达,疫苗免疫小鼠后能检测融合蛋白体内稳定表达.融合DNA疫苗能够延缓小鼠黑素移植瘤的生长,抑瘤率为54%(P<0.01);能延长荷瘤小鼠的生存期(疫苗组小鼠接种瘤细胞后30 d的生存率为40%);融合DNA疫苗诱发小鼠产生高滴度抗EGFR抗体(效价1∶1 000)和T细胞免疫(疫苗组小鼠脾脏CD8 T淋巴细胞数目显著增加, P<0.01).结论:cEGFR-rFc融合DNA疫苗能产生有效对抗黑素瘤B16细胞的免疫效应.     

截短的食管癌相关基因ECRG4在大肠杆菌中的可溶性表达及纯化

目的本实验旨在构建ECRG4的原核表达载体，在大肠杆菌中表达并纯化ECRG4所编码的蛋白，为进一步研究奠定基础。方法将ECRG4基因序列前端编码疏水性跨膜区28个氨基酸的cDNA序列截去，再将截短的cDNA序列克隆到原核表达载体Pet30（＋）上，重组表达载体转化感受态表达菌株BL21（DE3），低浓度IPTG低温诱导融合蛋白的表达。采用Western blot鉴定目的蛋白的表达，使用Ni-NTA亲和层析柱进行纯化。结果构建了截短的ECRG4．pET30a（＋）基因的原核表达载体，IPTG低温诱导得到大量可溶性蛋白，并且通过亲和层析纯化了重组融合蛋白。结论成功获得了高效表达的、具有一定的生物学活性的ECRG4原核表达产物，并为进一步研究ECRG4的结构和功能打下基础。     

More efficient induction of HLA-A*0201-restricted and carcinoembryonic antigen (CEA)-specific CTL response by immunization with exosomes prepared from heat-stressed CEA-positive tumor cells.

PURPOSE: Tumor-derived exosomes are proposed as a new type of cancer vaccine. Heat shock proteins are potent Th1 adjuvant, and heat stress can induce heat shock protein and MHC-I expression in tumor cells, leading to the increased immunogenicity of tumor cells. To improve the immunogenicity of exosomes as cancer vaccine, we prepared exosomes from heat-stressed carcinoembryonic antigen (CEA)-positive tumor cells (CEA+/HS-Exo) and tested the efficacy of these exosomes in the induction of CEA-specific antitumor immunity. EXPERIMENTAL DESIGN: First, we identified the composition of CEA+/HS-Exo and observed their effects on human dendritic cell maturation. Then, we evaluated their ability to induce a CEA-specific immune response in vivo in HLA-A2.1/Kb transgenic mice and CEA-specific CTL response in vitro in HLA-A*0201+ healthy donors and HLA-A*0201+CEA+ cancer patients. RESULTS: CEA+/HS-Exo contained CEA and more heat shock protein 70 and MHC-I and significantly induced dendritic cell maturation. Immunization of HLA-A2.1/Kb transgenic mice with CEA+/HS-Exo was more efficient in priming a CEA-specific CTL, and the CTL showed antitumor effect when adoptively transferred to SW480-bearing nude mice. Moreover, in vitro incubation of lymphocytes from HLA-A*0201+ healthy donors and HLA-A*0201+CEA+ cancer patients with CEA+/HS-Exo-pulsed autologous dendritic cells induces HLA-A*0201-restricted and CEA-specific CTL response. CONCLUSIONS: Our results show that CEA+/HS-Exo has superior immunogenicity than CEA+/Exo in inducing CEA-specific CTL response and suggest that exosomes derived from heat-stressed tumor cells may be used as efficient vaccine for cancer immunotherapy.     

Analysis of MAGE-3 derived synthetic peptide as a human lung cancer antigen recognized by cytotoxic T lymphocytes

BACKGROUND: The human MAGE-3 gene was originally discovered in melanoma cells that encode tumor antigens, and has been reported to be expressed in various types of tumors, including lung cancer, but not in normal tissues other than testis or placenta. Our aim in this study was to clarify whether HLA-A2 restricted MAGE-3 peptide (FLWGPRALV) could be a lung cancer antigen recognized by cytotoxic T lymphocytes (CTL). METHODS: MAGE-3-derived peptide-specific CTL were induced from the peripheral blood mononuclear cells (PBMC) of HLA-A0201-positive healthy donors and the regional lymph node lymphocytes (RLNL) of HLA-A2-positive patients with lung cancer by multiple stimulations with peptide-pulsed HLA-A0201-positive antigen-presenting cells. RESULTS: Lymphocytes stimulated with MAGE-3 peptide exhibited specific lysis of Epstein-Barr virus-transformed B cells (EBV-B) pulsed with MAGE-3 peptide, but not with control peptide derived from influenza matrix protein, erbB-2, or wild type p53. Specific activity for MAGE-3-presenting targets was found after the second stimulation, and increased depending on the number of stimulations. The peptide-specific activity was inhibited by the addition of monoclonal antibodies against MHC class I and HLA-A2. Such CTL also recognized tumor cell lines expressing both HLA-A2 and MAGE-3 in an MHC class I-restricted manner, but did not recognize tumor cell lines that did not express HLA-A2 or MAGE-3. CONCLUSION: These results suggested the MAGE-3 peptide could be a potential target of specific immunotherapy for HLA-A2 patients with lung cancer.     

Inducible Hsp70 as target of anticancer immunotherapy: Identification of HLA-A*0201-restricted epitopes

The design of a broad application tumor vaccine requires the identification of tumor antigens expressed in a majority of tumors of various origins. We questioned whether the major stress-inducible heat shock protein Hsp70 (also known as Hsp72), a protein frequently overexpressed in human tumors of various histological origins, but not in most physiological normal tissues, constitutes a tumor antigen. We selected the p391 and p393 peptides from the sequence of the human inducible Hsp70 that had a high affinity for HLA-A*0201. These peptides were able to trigger a CTL response in vivo in HLA-A*0201-transgenic HHD mice and in vitro in HLA-A*0201+ healthy donors. p391- and p393-specific human and murine CTL recognized human tumor cells overexpressing Hsp70 in a HLA-A*0201-restricted manner. Tetramer analysis of TILs showed that these Hsp70 epitopes are targets of an immune response in many HLA-A*0201+ breast cancer patients. Hsp70 is a tumor antigen and the Hsp70-derived peptides p391 and p393 could be used to raise a cytotoxic response against tumors of various origins.     

Identification of an HLA-A*0201 restricted Bcl2-derived epitope expressed on tumors

A large number of human tumor-associated antigen-derived peptides have been identified that are recognized by CTLs in a MHC-I restricted fashion. The apoptosis inhibitory protein Bcl2 is overexpressed in many human cancers as part of their neoplastic phenotype. Since inhibition or loss of Bcl2 expression might impair tumor growth and survival, this protein may serve as a rational target for vaccine-induced CTL responses. By Western blot technique, we screened a panel of established human tumor cell lines for proteins involved in the apoptotic process. Two of eight tumor cell lines, a B lymphoma (Loukes) and a colon carcinoma (CCL220) cell line showed increased Bcl2 protein expression whereas the majority of tumor cell lines expressed proapoptotic proteins. Neither fibroblasts nor peripheral blood mononuclear cells showed Bcl2 expression. An HLA-A*0201 restricted CTL epitope was deduced in silica from the amino acid sequence of the Bcl2 protein and its binding affinity for HLA-A*0201 was confirmed using a biochemical binding assay. We here demonstrate that the 9-mer peptide Bcl2(85-93) induces specific CTL reactivity in immunized C57-A2K(b) or -A2D(b) tg mice. These Bcl2(85-93) specific CTLs react with and lyse Bcl2-expressing human colon carcinoma CCL220 cells which have been transfected with a chimeric HLA-A*0201/H2-K(b) DNA construct similar to that expressed in the transgenic mice. Based on these observations, we suggest that Bcl2(85-93) may be a target for immune therapy.     

A newly identified MAGE-3-derived epitope recognized by HLA-A24-restricted cytotoxic T lymphocytes

Five MAGE-3-derived peptides carrying an HLA-A24-binding motif were synthesized. Binding capacity of these peptides was analyzed by an HLA-class-I stabilization assay. Two of the 5 peptides bound to HLA-A*2402 molecule with high affinity, and 3 peptides with low affinity. Peripheral-blood mononuclear cells (PBMC) depleted of CD4+T cells were stimulated with the peptides to determine whether these peptides would induce cytotoxic T lymphocytes (CTL) from PBMCs obtained from 7 healthy HLA-A*2402+ donors. Peptide M3-p97 (TFPDLESEF; corresponding to amino-acid residues 97-105 of MAGE-3), with high binding capacity to the HLA-A*2402 molecule, elicited the peptide-specific and HLA-A24-restricted CD8+CTL lines in 2 of the 7 donors, while none of the 4 other peptides induced CTL specific for the corresponding peptide in any of the donors. CTL lines induced by stimulation with peptide M3-p97 exhibited cytolytic activities against HLA-A*2402 transfectant cell lines (C1R-A*2402) in the presence of peptide M3-p97, but not in unloaded or irrelevant peptide-pulsed C1R-A*2402 cells. The CTL lines and a cloned CD8+CTL isolated from one of the bulk populations by limiting dilution could lyse MAGE-3+/HLA-A*2402+ squamous-cell-carcinoma(SCC) lines but neither MAGE-3-/HLA-A*2402+ nor MAGE-3+/HLA-A*2402- SCC lines, indicating that M3-p97 can be naturally processed and presented on the tumor-cell surface in association with HLA-A*2402 molecules. Combined with the 4 currently reported CTL epitopes derived from MAGE-3 and presented by HLA-A1, HLA-A2, HLA-A24 or HLA-B44, identification of this CTL epitope presented by the HLA-A*2402 molecule will extend the application of MAGE-3-derived peptides for immunotherapy for cancer patients.     

Generation of RAGE-1 and MAGE-9 peptide-specific cytotoxic T-lymphocyte lines for transfer in patients with renal cell carcinoma

Renal cell carcinomas (RCCs) are supposed to be immunogenic, and several clinical trials of immunotherapy using tumor lysate-pulsed dendritic cells (DCs) have been performed. We report on the generation of RAGE-1 and MAGE-9 peptide-specific CTL lines. RAGE-1 and MAGE-9 are expressed in 56% and 38% of RCCs. Seven MAGE-9- and 13 RAGE-1-derived peptides were found to be immunogenic in the context of the HLA-A*0201 MHC. CTLs were generated by coculture with peptide-pulsed, activated B cells, which were easily generated in great quantities and displayed functional activity for a prolonged period of time. MAGE-9 and RAGE-1 peptide-specific CTL lines were strictly peptide-specific and displayed high cytotoxic activity not only against peptide-loaded T2 cells but also against HLA-A*0201-positive RCC lines, which naturally express MAGE-9, RAGE-1 or both. Thus, B cells are well suited as APCs for the generation of large numbers of tumor peptide-specific CTLs for adoptive transfer. MAGE-9 as well as RAGE-1 may well provide suitable targets for immunotherapy of RCC.     

Inhibition of tumor growth with antiangiogenic cancer vaccine using epitope peptides derived from human vascular endothelial growth factor receptor 1.

PURPOSE: Antiangiogenic therapy is now considered to be one of promising approaches to treat various types of cancer. In this study, we examined the possibility of developing antiangiogenic cancer vaccine targeting vascular endothelial growth factor receptor 1 (VEGFR1) overexpressed on endothelial cells of newly formed vessels in the tumor. EXPERIMENTAL DESIGN: Epitope-candidate peptides were predicted from the amino acid sequence of VEGFR1 based on their theoretical binding affinities to the corresponding HLAs. The A2/Kb transgenic mice, which express the alpha1 and alpha2 domains of human HLA-A*0201, were immunized with the epitope candidates to examine their effects. We also examined whether these peptides could induce human CTLs specific to the target cells in vitro. RESULTS: The CTL responses in A2/Kb transgenic mice were induced with vaccination using identified epitope peptides restricted to HLA-A*0201. Peptide-specific CTL clones were also induced in vitro with these identified epitope peptides from peripheral blood mononuclear cells donated by healthy volunteers with HLA-A*0201. We established CTL clones in vitro from human peripheral blood mononuclear cells with HLA-A*2402 as well. These CTL clones were shown to have potent cytotoxicities in a HLA class I-restricted manner not only against peptide-pulsed target cells but also against target cells endogenously expressing VEGFR1. Furthermore, immunization of A2/Kb transgenic mice with identified epitope peptides restricted to HLA-A*0201 was associated with significant suppression of tumor-induced angiogenesis and tumor growth without showing apparent adverse effects. CONCLUSIONS: These results strongly suggest that VEGFR1 is a promising target for antiangiogenic cancer vaccine and warrants further clinical development of this strategy.     

A polyepitope DNA vaccine targeted to Her-2/ErbB-2 elicits a broad range of human and murine CTL effectors to protect against tumor challenge

A cDNA vaccine (pVax1/pet-neu) was designed to encode 12 different Her-2/ErbB-2-derived, HLA-A*0201-restricted dominant and high-affinity heteroclitic cryptic epitopes. Vaccination with pVax1/pet-neu triggered multiple and ErbB-2-specific CTL responses in HLA-A*0201 transgenic HHD mice and in HLA-A*0201 healthy donors in vitro. Human and murine CTL specific for each one of the 12 ErbB-2 peptides recognized in vitro both human and murine tumor cells overexpressing endogenous ErbB-2. Furthermore, vaccination of HHD mice with pVax1/pet-neu significantly delayed the in vivo growth of challenged ErbB-2-expressing tumor (EL4/HHD/neu murine thymoma) more actively when compared with vaccination with the empty vector (pVax1) or vehicle alone. These data indicate that the pVax1/pet-neu cDNA vaccine coding for a poly-ErbB-2 epitope is able to generate simultaneous ErbB-2-specific antitumor responses against dominant and cryptic multiple epitopes.     

食管癌高表达抗原HLA-A2/A3 限制性细胞毒性T 淋巴细胞表位预测

 目的 预测食管癌普遍高表达蛋白COX-2和MAGE-4的HLA-A2/A3限制性CTL表位。方法运用生物信息学的方法,SYFPEITHI初步预测,结合三维构效定量关系和蛋白酶体酶切位点分析。结果 对SYFPEITHI预测〉20的九肽用MHCPred和NetChop3.0作进一步分析,并与已报道抗原肽进行比对,初步筛选出了42个潜在的CTL表位。结论 这42个九肽均未见文献报道,进一步鉴定将为CTL表位疫苗的研究提供更多的线索。其中,MAGE-422-30、202-210、286-294及COX-2479-4874个九肽具有与HLA-A2和HLA-A3超型潜在的交叉免疫活性,将为研制简约的高效广谱食管癌疫苗提供候选肽。     

HER-2, gp100, and MAGE-1 are expressed in human glioblastoma and recognized by cytotoxic T cells

It has recently been demonstrated that malignant glioma cells express certain known tumor-associated antigens, such as HER-2, gp100, and MAGE-1. To further determine the possible utilization of these antigens for glioma immunotherapy and as surrogate markers for specific tumor antigen cytotoxicity, we characterized the presence of mRNA and protein expression in 43 primary glioblastoma multiforme (GBM) cell lines and 7 established human GBM cell lines. HER-2, gp100, and MAGE-1 mRNA expression was detected in 81.4%, 46.5%, and 39.5% of the GBM primary cell lines, respectively. Using immunoreactive staining analysis by flow cytometry, HER-2, gp100, and MAGE-1 protein expression was detected in 76%, 45%, and 38% of the GBM primary cell lines, respectively. HLA-A1-restricted epitope specific for MAGE-1 peptide (EADPTGHSY) CTL clone B07 and HLA-A2-restricted epitope specific for HER-2 peptide (KIFGSLAFL) CTL clone A05 and gp100 peptide (ITDQVPFSV) CTL clone CK3H6 were used in this study. The specificity of CTL clone was verified by HLA/peptide tetramer staining. Three CTL clones could efficiently recognize GBM tumor cells in an antigen-specific and MHC class I-restricted manner. IFN-gamma treatment can dramatically increase MHC class I expression of GBM tumor cells and significantly increase CTL recognition of tumor cells. Treatment with the DNA hypomethylating agent 5-aza-2'-deoxycytidine induced and up-regulated the mRNA expression of MAGE-1 and epitope presentation by autologous MHC. These data indicate that HER-2, gp100, and MAGE-1 could be used as tumor antigen targets for surrogate assays for antigen-specific CTLs or to develop antigen-specific active immunotherapy strategies for glioma patients.