利用RT-PCR克隆出共刺激分子人B7(CD80)的全部编码cDNA,将其插入E1区替代的腺病毒载体pAxlcw,选择左向转录的CD80重组腺病毒载体pAxlcw.CIhCD80,与经EcoT221酶切的Ad5腺病毒DNA-末端肽复合物共转染293细胞,通过同源重组获得人CD80的复制缺陷性重组腺病毒,扩增到的病毒滴度为4×10~9pfu/ml;重组腺病毒感染Hela细胞,48小时后经流式细胞仪检测表达高水平的CD80,表明所制备的复制缺陷性重组腺病毒能有效表达人CD80.

In this study, we demonstrated that immobilized fibronectin (FN) enhanced LAK activity, and that the enhanced LAK activity was completely abrogated by an anti-VLA-5 monoclonal antibody and RGD peptide. Fresh -spleen cells expressed VLA-4, VLA-6 and vitronectin receptor, whereas VLA-5 was expressed only on the spleen cells activated with IL-2. LAK cells showed increased adhesion to immobilized FN compared with that to control BSA, and the increased adhesion of LAK cells to immobilized FN was inhibited by anti-VLA-5 monoclonal antibody. Conjugate-formation assay showed that the LAK cells cultured on immobilized FN bound to target cells more efficiently than the control LAK cells, and that anti-LFA-1 monoclonal antibody inhibited the LAK-target cell binding. Immobilized type IV collagen and laminin, as well as FN, enhanced LAK activity. All these results suggest that the interaction of inte-grins expressed on LAK cells with extracellular matrix proteins act as co-stimulator for the enhancement of LAK activity , and that anchorage is necessary for full activation of LAK cells.

R730.3

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