| 1. | Tumor antigens of hepatocellular carcinoma and its specific cellular immunity
肝癌的肿瘤抗原与特异性细胞免疫 |
| 2. | Tumor cell - derived exosomes containing tumor antigens and mhc class i molecule could present tumor antigens to dcs and induce cd8 + t cell - dependent antitumor immune responses significantly
其含有mhc类分子和lamp - 1 ，能够将肿瘤抗原呈递给抗原递呈细胞，产生显著的cd8 ~ + t细胞依赖的抗肿瘤免疫反应。 |
| 3. | Objective from 1990s , the successful cloning of many tumor antigen genes of human kind has driven the development of tumor immunology enormously . and so does it to the application of tumor immunodiagno sties and immunotherapy
目的： 20世纪90年代以来，多种人类肿瘤抗原基因克隆的成功，大大推动了肿瘤免疫学理论的发展，也促进了肿瘤免疫诊断和免疫治疗的应用。 |
| 4. | Though with various advantages , these tumor vaccines are because of complicated to prepare , restricted availability of relevant tumor antigens , the lack of molecularly defined tumor antigen delivery or targeting systems and the effects are relatively not promising
这些肿瘤疫苗的制备机理均在于提高对肿瘤抗原的递呈作用。缺点是制备工艺复杂、效果相对不够理想。 exosomes是由多种细胞分泌的来源于多囊泡体的小的膜性囊泡。 |
| 5. | At present , in an attempt to stimulate specific antitumor immunity , experimental models and clinical studies are currently evaluating the potent antigen - presenting capacity of dc combined with single or multiple tumor antigen epitopes . however , there are several problems in utilizing pulsing dc with synthetic immunodominant peptides from identified antigens . 1 ) the potential induction of tolerance ; 2 ) the need to determine the patient ' s hla haplotype , the limitation of therapy to patients whose tumors express defined specific tumor antigens in the context of the correct hla phenotype , the unavailability of peptides for all hla haplotypes ; 3 ) the lack of cd4 help cell - related epitopes for most antigens ; and 4 ) the ctl resulting from such protocols have a good in vitro capacity to kill peptide - pulsed target cells but only a modest capacity to kill tumor cells
但是，学者们发现这一疗法存在着如下的缺陷：单一ctl表位抗原肽的应用其抗肿瘤作用弱于多种肿瘤抗原的联合应用，且有诱导免疫耐受的潜在危险，有时反而会促进肿瘤的生长；事先需对患者的hla单倍型进行鉴定，以确定ctl表位与hla单倍型是否匹配，目前尚缺乏能与所有hla单倍型相匹配的ctl表位，从而限制了这一疗法的应用；这一疗法所产生的ctl在体外能有效杀伤经肿瘤抗原肽共孵育过的靶细胞，但对肿瘤细胞的杀伤能力较弱：这种l表位抗原肽缺乏cd4汀h细胞相关的表位，因此，不能诱导有效的th细胞免疫应答。 |
| 6. | Methods employed to prepare vaccine include rumor cells genetically modified with cytokines , costimulatory molecules and tumor antigenic peptides , dendritic cells ( dc ) primed with tumor antigens in vitro or genetically modified with tumor antigens , or fusion of tumor cells with antigen presenting cells ( apc )
现有的比较受到关注的制备肿瘤疫苗的方法有各种细胞因子、共刺激分子、肿瘤抗原肽等基因修饰的肿瘤细胞疫苗；体外抗原致敏的或肿瘤抗原肽基因修饰的树突状细胞疫苗；肿瘤细胞与抗原递呈细胞融合疫苗等。 |
| 7. | Dcs play a pivotal role in the development of antitumor immunity . t lymphocytes immune response induced by direct antigen - pulsed dcs can not maintain longer for peptides - mhc department or mhc molecules degeneration . the method of dcs loading with tumor antigen gene is another potential approach to enhancing and maintaining immune response
在用抗原直接刺激dc时，由于抗原- mhc复合物解离或细胞mhc分子降解而不能维持所诱导的t细胞免疫应答，借助载体把肿瘤抗原基因导入dc后肿瘤抗原在dc内的持续表达能增强其抗原提呈能力并能维持所诱导的免疫效应。 |
