细胞粘附分子P-selectin功能片段在CHO细胞表面的锚定表达

Eukaryotic Expression of P-selectin Functional Segment on the Membrane of CHO

摘要:

为了筛选出针对细胞粘附分子P-selectin的特异性抗体, 克隆了P-selectin功能性基因片段, 使其通过糖基化磷脂酰肌醇(GPI)锚定表达于真核细胞的细胞膜上, 以用作筛选的抗原。提取人血小板的总RNA, RT-PCR扩增出P-selectin目的基因片段, 同时用重叠延伸PCR的方法合成细胞膜锚定信号肽GPI基因; 将二者按上下游顺序插入含有弱化neo基因的真核表达载体pMCEw2中; 并将构建的重组质粒pMCEw2-GPI-P-selectin转染CHOdhfr-细胞, G418筛选获得阳性细胞株, 利用ELISA、免疫印迹和免疫荧光法检测P-selectin的表达。实验证实了P-selectin在细胞膜上获得稳定表达。为进一步进行抗P-selectin的特异性抗体的筛选提供了必要前提。

Abstract:

Cell adhesive molecular P-selectin was cloned, expressed and anchored on CHO cell membrane through GPI for selection specific antibodies. Total human platelet RNA was extracted and the functional segment of P-selectin gene was cloned by RT-PCR. The P-selectin functional segment gene was cloned into a eukaryotic expression vector pMCEw2-GPI containing an attenuated neo gene together with a downstream GPI, which was synthesized by overlapping PCR. The recombinant plasmid pMCEw2-GPI-P- selectin was then transfected to CHOdhfr- cells and screened with G418. ELISA, western-blot and immunofluorescence were carried out to detect the stability of P-selection expression on cell membrane. These results provided a necessary basis for the following study of selection the antibodies targeting P-selectin.