Table 3.

Product quality assessment during clone selection

Quality attribute	Analytical assay	Quality assessment criteria
Molecule integrity	cDNA sequence, Peptide mapping, CE-SDS or SDS-PAGE	Avoid amino acid sequence mutation or truncated antibodies
Aggregation	Size Exclusion Chromatography (SEC)	Avoid high level of aggregation, which could be immunogenic.
Glycosylation	HPLC or CE based glycan assay	Avoid high levels of unusually glycosylation forms
Charge heterogeneity	IEF or iCIEF, Ion Exchange Chromatography HPLC	Avoid usually high levels of acidic or basic variant, or extra acidic or basic peaks

CE, capillary electrophoresis; IEF, Isoelectric focusing; iCIEF, Imaged capillary isoelectric focusing.