Ⅰ-A^k基因克隆转导及对肿瘤细胞成瘤的影响

MHC class Ⅱ ⅠAkαβ Gene Transfer and the Influence on Tumor Growth

采用ＲＴＰＣＲ方法合成小鼠ＭＨＣⅡ类分子ⅠＡｋ基因α和β链ｃＤＮＡ，插入逆转录病毒载体ｐＬＳＸＮ，构建ⅠＡｋα和ⅠＡｋβ表达载体，采用脂质体介导的重组质粒转移方法将ⅠＡｋα和ⅠＡｋβ基因导入ＥＬ４小鼠淋巴瘤细胞和Ｐ８１５小鼠肥大细胞瘤细胞，经流式细胞仪检测在细胞表面有ⅠＡｋ表达．将以上两种细胞注射到同源小鼠Ｃ５７ＢＬ／６（Ｈ２ｄ）皮下，观察到肿瘤产生后又消退，证明在肿瘤细胞中单独导入同种异型ＭＨＣⅡ类分子基因也能激活肿瘤的细胞免疫，为进一步开展肿瘤的基因治疗奠定了基础．

In order to search the influence of ⅠAkαβ gene transfer on the growth of the transferred mouse tumor cells in vivo, the α and β chain cDNA were synthesized, and inserted into a retroviral vector, to construct two ⅠAk expressing recombinant plasmids pLSXNAkα and pLSXNAkβ. By means of a liposomemediated gene transfer procedure, these two recombinant plasmids together were introduced into mouse lymphoma EL4 cells and mastocytoma P815 cells. The expression of the ⅠAkαβ protein on the surface of the transconducted tumor cells was tested by FACS using AntiAkFITC. Afterwards these tumor cells were injected subcutaneously into autologous mice C57BL/6(H2b) and DBA/2(H2d) respectively. It was observed that tumors developed at the beginning within the mouse bodies, and disappeared after a few weeks with injection. While the nontransferred tumor cells grew continuously. These results show that the tumor immune response can be stimulated by the tumor cells transferred with allogenic MHC class Ⅱ gene, in the absence of B7 costimulatory signals.