Human glyco-engineered CHO cells

Human Glyco engineered CHO Cells Abstract Glycosylation is well known to modulate the activity of therapeutic proteinsRecentlysialylation of the N linked glycan chains has been shown to significantly affect recombinant glycoprotein stability and activityFor examplethe degree of sialylation directly correlates with serum half lifeSialic acids are also important modulators of immunogenicitya major problem with protein based therapeuticsImmunogenicity inversely correlates with the degree of sialylationNegatively charged sialic acids influence protein specific parameters like thermal stabilityresistance to proteolysisand solubilityDespite the importance of sialylationsialic acid incorporation by the production platforms in wide use todayincluding Chinese hamster ovaryCHOcellsis inefficient and highly variablea product consistency issueVariable sialylation is due largely to the activity of sialidasesas is the incorporation of the non human sialic acid Neu Gcto which most humans possess antibodiesThereforeit is of great interest to develop methods or platforms to yield uniformly sialylated proteins with a fully human sialylation profileWhile several methods have been described to address sialic acid incorporationnone has yet been widely adopted due to inefficiencies or the increased cost of productionIn phasewe utilized the CRISPR Cas system for genome engineering to develop a proprietary method for rapidefficient generation of homozygous negative cell linesDouble allele KnockoutDAKOtechnologyDAKO was used for successful deletion of two sialidases in CHO cellsDuring this Phase II projectwe will utilize these cells to produce an improved alphaantitrypsinA ATwith human like sialyation glycosylation and will investigate the role of glycosylation in A AT activity using animal modelsIn addition to A ATantibodies and other glycoproteins produced in these cells will have a high degree of sialic acid incorporation