“…These platforms include optimized vector systems, selection and amplification protocols, sophisticated and partly automated screening procedures as well as media and process platforms tailor-made for the individual needs of the CHO host cell clone. Moreover, transcriptomics (Nissom et al, 2006;Birzele et al, 2010;Kantardjieff et al, 2010), proteomics (Meleady, 2007;Pascoe et al, 2007) and metabolomics approaches (Nolan and Lee, 2011;Chong et al, 2010) have been used to elucidate the regulatory mechanisms within this host cell and genetic modifications might have been introduced to enhance viability, cellular productivity or other beneficial properties (for review, see also Kuystermans et al, 2007;Mohan et al, 2008). Thus, high titers achieved through effec- tive gene amplification as well as the know-how built around them made DHFR-deficient CHO cells very successful production host cells for the biopharmaceutical industry.…”