Preparation and Testing of Monoclonal Antibodies to Recombinant Proteins

Monoclonal antibodies (MAbs) are essential reagents for the isolation, identification, and cellular localization of specific gene products and for aiding in the determination of their macromolecular structure. They can also help in identifying the function of the protein. Although the ability to clone and sequence specific genes has revolutionized our understanding of cellular structure and function, the preparation of recombinant proteins and the synthesis of peptides based on protein sequences derived from cDNA clones have provided sufficient material for generating specific antibodies. The proteins may be isolated and purified directly from cells, or recombinant proteins may be derived from prokaryotic systems, such as Escherichia coli , or from eukaryotic expression systems, such as Chinese hamster ovary (CHO) cells, or insect cells expressing constructs in baculovirus . The eukaryotic systems are being used increasingly for expression of glycoproteins, because the recombinant material is glycosylated. It should be remembered, however, that glycosylation may be species-specific and if one of the functions of the protein depends on carbohydrate, then the function of a recombinant glycoprotein may be altered depending on the species used for expression.