The Patheon process for high density cell culture (Patheon XD® Upstream Processing (USP) technology) can result in up to a 25 fold increase in bioreactor output (cell density). CHO cell lines can be engineered to deliver maximal performance and productivity. The proprietary Patheon XD® USP bioprocess may be improved for suitability to high density culture, by engineering CHO cell lines with acquired properties that favour high density. In this project, development of a cell line(s) optimised for high density cell culture, utilising CRISPR and other cell line engineering techniques, will be investigated.