高效分离人白细胞介素—2CDNA克隆的新技术

白细胞介素—2是免疫应答过程中由T细胞释放的一种淋巴因子,具有较广泛的生物学作用。本文报告采用负向选择增富法处理人外周血淋巴细胞cDNA文库,用一种新型非放射标记技术制成地高辛素-dUTP-鼠白细胞介素-2cDNA片段探针,从中筛选到2个阳性克隆,使阳性率提高33倍。经限制性内切酶谱分析,所获克隆与公布的人白细胞介素-2cDNA顺序相符。该cDNA转染CoS-7细胞后表达的重组人白细胞介素-2可维持小鼠白细胞介素-2依赖株FI-2生长。

A New Method for Isolating Human IL-2 cDNA Clone with High Efficiency

Interleukin-2(IL-2) has a very broad spectrum of activities and plays an important role in immune regulation. The cDNA clones encoding human IL-2 were gained from human PBL cDNA library with a nonradioactive digoxigenin-probe prepared from mouse IL-2 cDNA clone. In order to increase the screening efficiency, we pretreated the library with a serieys of restriction enzymes which were not present within human IL-2 cDNA and plasmid vector and made the positive rate of human IL-2 clone raise 33 times as high as that of the primary library.By this "reverse selecting method" , two cDNA clones were isolted and identified by restriction mapping-The COS-7 cells were transfec-ted with the isolated cDNA clone(in pcD plasmid vector) and the resulting supernatants could effectively maintain in vitro growth of mouse IL-2 dependent line FI-2.