Fam60A plays a role for production stabilities of recombinant CHO cell lines

Abstract

Recombinant CHO (Chinese hamster ovary) cell lines producing therapeutic proteins often lose their production capability during long-term cultivation. To ensure that CHO production cell lines can be up-scaled to high-volume bioreactors, labor intensive stability studies of several months have to be performed to deselect clones that are losing productivity over time. The ability to predict whether clones will produce recombinant proteins at constant high levels, for example, through determination of biomarkers such as expression of specific genes, plasmid integration sites, or epigenetic patterns, or even to improve CHO host cell lines to increase the probability of the generation of stable clones would be highly beneficial. Previously, we reported that the lack of a telomeric region of chromosome 8 correlates with increased productivities and higher production stabilities of monoclonal antibody expressing CHO cell lines (Ritter A, Voedisch B, Wienberg J, Wilms B, Geisse S, Jostock T, Laux H. 2016a. Biotechnol Bioeng 113(5):1084-1093). Herein, we describe that the knock-out of the gene Fam60A, which is one of the genes located within the telomeric region of chromosome 8, in CHO-K1a cells leads to the isolation of significantly more clones with higher protein production stabilities of monoclonal antibodies during long-term cultivation. Biotechnol. Bioeng. 2017;114: 701-704. © 2016 Wiley Periodicals, Inc.

Enhanced CHO Clone Screening: Application of Targeted Locus Amplification and Next‐Generation Sequencing Technologies for Cell Line Development

“…The labor‐intensive clone screening phase is nowadays often performed by robotics and in small‐scale bioreactor systems that reduce the workload of screening for suitable clones. Clone screening and selection involve a number of analytical screens to ensure an assortment of the top clones, which should produce a recombinant protein with high titers, favorable product quality attributes and stability without losing productivity over time …”

Multiplex secretome engineering enhances recombinant protein production and purity

“…The dramatically lowered HCP ppm values during purification of a mAb will facilitate downstream processes. These HCP-reduced knockouts can be combined with additional advantageous genetic modifications, such as the production of glycoengineered proteins [15][16][17][18] , higher viability during long culture times 19 , viral resistance or elimination [20][21][22] , and/or clones with higher protein production stability of mAbs 23 , to create predictable upstream and downstream processes with full control over critical process parameters.…”

Loss of FAM60A attenuates cell proliferation in glioma via suppression of PI3K/Akt/mTOR signaling pathways

“…FAM60A is required for proper embryogenesis due to its regulation of DNA methylation at specific gene promoters [13] . FAM60A is crucial in the production stabilities of recombinant CHO cell lines [22] . However, FAM60A has an N-terminal conserved GATA-like zinc finger motif, showing that it may bind to DNA in transcriptional regulation.…”