Establishment of a human cell line highly expressing endothelin in serum-free medium

Human preproendothelin-1 (prepro-ET-1) was transfected into an immortal human endothelial cell line that had been cultivated in a serum-free medium. Several transformants selected with Ecogpt selection were probed to have prepro-ET insert, express prepro-ET-1 mRNA, and secrete immunoreactive ET (ir-ET). One of the transformants, t-HUE2-1, secreted 30 times the amount of ET-1 and the ratio of mature ET-1 to big ET-1 was 11-fold higher compared with normal human endothelial cells. Thus, this transformant might be of use to study regulation of the posttranscriptional process of prepro-ET-1 in human cells.