Refolding Technology for scFv Using a New Detergent, N-Lauroyl-L-glutamate and Arginine

Monoclonal antibodies to the soluble antigens or cell surface markers hold great promise as effective human therapeutics. One of the major disadvantages is its large size, which prevents efficient penetration into the target tissues. Smaller version of antibodies, which has only antigen binding sites, is extensively investigated. It becomes increasingly apparent, however, that these smaller fragments of antibodies are rather difficult to produce, as the normally efficient mammalian secretion system does not work well for these fragments. Thus, refolding of insoluble proteins produced in Escherichia coli is a method of choice, although such refolding is mainly based on trial-and-error experiment. Here we describe a novel refolding system using a new amino acid-based detergent, N-lauroyl-L-glutamate, and arginine. This detergent appears to readily dissociate from proteins below critical micelle concentration (CMC), while remaining effective in protein solubilization above CMC. Arginine suppresses protein aggregation when the detergent concentration was reduced below CMC. The interaction of the detergent and arginine with proteins, which play an important role in protein refolding, will be discussed in great length.