id	author	title	date	pages	extension	mime	words	sentences	flesch	summary	cache	txt
cord-348360-20eq5meh	Esposito, Dominic	Optimizing high-yield production of SARS-CoV-2 soluble spike trimers for serology assays	2020-06-04		.txt	text/plain	3438	158	49	To improve the yield of spike protein and support the high demand for antigens in serology assays, we investigated several recombinant protein expression variables by altering the incubation temperature, harvest time, chromatography strategy, and final protein manipulation. Thus, the work presented here is intended to provide a robust method for those wishing to reliably produce SARS CoV-2 spike protein in quantities sufficient for serology assays, structural biology, or simply to better understand some of the production variables affecting the yield. Nevertheless, the approaches outlined here allowed us to improve the production yield of spike protein significantly by modifying cell culture temperature and harvest time, as well as improving the purification process. To produce SARS-CoV-2 antigens for the development of serology assays, we initially followed standard procedures for secreted protein production: transfection using the manufacturer's protocols, expression at 37°C, harvest at three days post-transfection, tangential flow filtration of the culture supernatant, immobilized metal ion chromatography with linear gradient elution, and size exclusion chromatography.	./cache/cord-348360-20eq5meh.txt	./txt/cord-348360-20eq5meh.txt