Antibodies and their derivatives are increasingly important as biotherapeutics, precision diagnostics, and essential tools for biological research. Techniques to screen and characterize large numbers of antibodies and provide confident selection of the best candidates for development are therefore essential. Biacore 4000 equipped with Biacore 4000 Antibody Extension Package has been used for efficient screening and characterization of antibody fragments for diagnostic purposes. Ten 96-well plates containing avian scFv fragments in crude cell lysates were screened and ranked in less than 20 h. A subset from this screen was selected for analysis with the 2-over-2 kinetics approach. This method provides rapid screening in combination with data-rich selection of fragments with high affinity and the desired kinetic behavior. Kinetic analysis at different temperatures provided additional information on the temperature stability of the selected fragments with respect to affinity. Chimeric chicken/human Fab fragments were screened and characterized using a preoptimized Human Fab Capture Kit to achieve accurate off-rate determination during initial screening of crude samples. These experiments demonstrate a new dimension for better-informed, more efficient selection of antibody fragments.
April 28, 2016