Towson University Glen Arm, Maryland, United States
Abstract Text: Phage display is a powerful protein engineering technique that utilizes the diversity of a bacteriophage library to select polypeptides with specific binding properties. The library is composed of phages that are engineered to display different polypeptide sequences on the surface of their coat proteins. Phage display involves several rounds of selection in which the phage library is incubated with a target protein immobilized on a solid surface. Phages that bind to the target protein undergo affinity purification and amplification. After several rounds of selection, the phage genome is sequenced to identify polypeptide sequences that bind with high affinity to the target. Phage display has many applications, including developing therapeutics, studying protein-protein interactions, and discovering antibody epitopes. We are using a phage display library expressing dodecamer polypeptides to discover a polypeptide sequence that binds to the CD8 alpha protein, found primarily on the surface of cytotoxic T-cells. This sequence could be used to recruit CD8+ T-cells for targeted cell killing, such as for killing cancer cells. We predict that phage display can also be utilized to discover the epitope bound by OKT8, a unique anti-CD8 antibody that stimulates T-cell activation. This information will be useful in developing immunotherapeutics by employing a CD8-targeted polypeptide to identify and recruit T cells and elucidating a stimulatory T-cell epitope on CD8.
