Characterization of recombinant glycosylated human interleukin 2 produced by a recombinant plasmid transformed CHO cell line

Autor: Ferrara, P., Pecceu, F., Marchese, E., Vita, N., Roskam, W., Lupker, J.
Zdroj: FEBS Letters; January 1987, Vol. 226 Issue: 1 p47-52, 6p
Abstrakt: A recombinant plasmid containing expression units for human pre-interleukin 2 (pre-IL-2) and the selectable marker mouse DHFR, was constructed and used to transform DHFR −CHO cells to the DHFR +phenotype. Selected colonies were isolated and tested for IL-2 production. Twelve highly IL-2-producing clones were amplified in stepwise increasing concentrations of methotrexate. The IL-2 secreted into the culture medium by one of these clones was purified to homogeneity and partially characterized. N-terminal sequence analysis showed that pre-IL-2 was correctly processed during secretion. SDS gel electrophoresis and chromatofocusing experiments in conjunction with neuraminidase treatment indicated a posttranslational glycosylation of the secreted mature protein similar to that described for the tetrasaccharide structure of the N2 form of natural IL-2. This recombinant IL-2 has a specific activity of 2.5 × 10 7U/mg.
Databáze: Supplemental Index