Optimized dual assay for the transgenes selection and screening in CHO cell line development for recombinant protein production.

Objective: To develop a simple robust methodology of screening multiple CHO cell clones secreting recombinant proteins to assess their specific productivity.

Results: We developed a dual assay based on immunoassay measurements of a recombinant protein expression combined with staining of viable cells with resazurin. Following this approach, colonies can be simultaneously assessed for cell growth rate and for production of a recombinant protein.