人白细胞介素-11基因在家蚕培养细胞和虫体内的表达

将缺少编码信号肽序列的人白细胞介素－11（hIL-11)546核苷酸cDNA，重组于质粒pBacPAK8构建重组转移载体pBacIL-11，与经线性化修饰的家蚕核型多角体病毒（BmBacPAK)DNA共转染家蚕培养细胞株BmN，获得了插入hIL-11基因的重组病毒。Southern杂交表明重组病毒基因组中含有hIL-11基因片段，RNA斑点杂交表明hIL-11基因得到了转录。重组病毒感BmN细胞株、家蚕幼虫和蛹，在细胞培养上清、细胞抽提物、幼虫和蛹的体液样品中，SDS－PAGE电泳分析都能检测得到表达产物的特异性条带；采用IL－11依赖细胞株B9－11和MTT法测定表达产物的生物活性，表明rIL-11基因分别在培养细胞和蚕体内得到了高效表达。

Expression of Human Interleukin-11 in Cell Culture and Larvae of Silkworm

A recombinant transfer vector, pBacIL-11, containing hIL-11 cDNA of 546 nucleotides lacking leader sequence was constructed and co-transfected into BmN cells with linearized BmBacPAK(modified BmNPV) DNA for construction of a recombinant baculovirus carrying the hIL-11 gene. Southern hybridization analysis suggested that the recombinant baculovirus DNA contained hIL-11 cDNA fragment.RNA dot blotting demonstrated that the hIL-11 gene was transcribed. The recombinant baculovirus has a strong infectivity to BmN cell line and to silkworm larvae and pupae. Specific hIL-11 bands were detected from all the samples of cell extract, culture supernatant, haemolymph of larvae and pupae by SDS-PAGE analysis. Biological activity of the expressed product was determined with IL-11 dependent B 9-11 cell line and by MTT colorimetric assay, which indicated that biolo gically active rhIL-11 protein was overexpressed in BmN cell line and in silkworm larvae and pupae.