In this approach, researchers can simply transfect their preferred host cell—in most cases, human embryonic kidney (HEK) 293 cells—with all three plasmids in a stepwise procedure (see Figure 1).

Clonal colonies of transfected CHO, HEK293 or myeloma cells secreting a recombinant protein of interest are probed in situ with target protein–specific, fluorophore-conjugated antibody ...