Novartis AG
Cell surface display of polypeptide isoforms by stop codon readthrough

Abstract:

A method for selecting mammalian host cells that express a polypeptide of interest with high yield is described. The host cells comprise an expression cassette comprising at least a first polynucleotide encoding the polypeptide of interest, at least one leaky stop codon downstream of the first polynucleotide, and a second polynucleotide downstream of the leaky stop codon encoding an immunoglobulin transmembrane anchor. The host cells are cultivated to allow expression of the polypeptide of interest such that at least a portion of the polypeptide of interest is expressed as a fusion polypeptide that is displayed on the cell surface. The cells are selected based upon the presence or amount of the displayed fusion polypeptide. Also provided are methods for producing a polypeptide that employ a respective selection to identify high expressing host cells.