Developing selection strategy for CHO-K1 cell line that secretes scfv-Fc fusion antibodies using ClonePix2

Abstract

In the pharmaceutical industry, biopharmaceuticals (biologics) are gaining market share. There has been a dramatic increase in the sale and market penetration of monoclonal antibodies in particular. Typically, therapeutic antibodies are produced using high-expression, clonal, or recombinant CHO cell lines. CHO cells dominate the market as a commercial production host due to their ease of use, built-in regulatory records, and security profiles. While traditional limiting-dilution and cloning-ring regulations are frequently used to select mammalian cell lines that produce high levels of proteins, they have a number of drawbacks. ClonePix2 is a fully automated, single cell-based clone selector that significantly increases the likelihood of rapidly selecting high-production clones with high monoclonality. Scfv-Fc recombinant antibody structures with a variety of therapeutic advantages have gained prominence in recent years. Single cell cloning of CHO cells expressing the scfv-Fc fusion protein, which differs from the classical immunoglobulin structure, was performed in situ using the ClonePix2 device using FITC-tagged anti-Fc and anti-H+L antibodies. The fluorescent intensity parameters of the resulting cell clones were analyzed. Additionally, ELISA was used to determine the production capacities of the best clones. As a result, it was established that anti-Fc antibody recognizes the scfv-Fc fusion protein in a semi-solid environment, enabling the identification of higher production clones.