A clone screening method using mRNA levels to determine specific productivity and product quality for monoclonal...

To meet increasing demands for efficient and streamlined production processes of therapeutic antibodies, improved methods of screening clones are required. In this article, we examined the potential of using antibody transcript levels as criteria for clone screening. We evaluated the QuantiGene Plex, a commercially available, high-throughput assay for simultaneously measuring multiple transcripts from cell lysate. Using the development of stable Chinese hamster ovary cell lines as examples, we investigated the relationship between transcript and antibody levels through several rounds of screening. First, we observed that measured heavy chain transcript levels are generally correlated with specific productivity, enabling the identification of high-producing clones from mRNA. Second, we observed that low ratios (< 1.5) of light to heavy chain transcript levels may be indicative of high antibody aggregation levels, allowing for the rapid identification and elimination of clones of questionable product quality. Therefore, an efficient process of identifying high-producing clones of desirable product quality is possible by using QuantiGene Plex assay to measure antibody transcript levels.