Patent ID: 9701958
Date: 2017-07-11
CPC Classifications: C07K,C12N,C40B

Claim:
1. A method for selecting polynucleotides that encode an antigen-specific immunoglobulin heavy chain variable region or antigen-binding fragment thereof, comprising: (a) introducing a first library of polynucleotides, each polynucleotide comprising a nucleic acid molecule encoding a heavy chain fusion protein, into a population of host cells permissive for vaccinia virus infectivity, wherein the first library of polynucleotides is constructed in a vaccinia virus vector, and wherein each heavy chain fusion protein comprises: i. a first polypeptide segment comprising an immunoglobulin heavy chain variable region or fragment thereof; ii. a second polypeptide segment comprising an immunoglobulin heavy chain constant region or portion thereof situated downstream of the first polypeptide segment, and iii. a third polypeptide segment situated downstream of the second polypeptide segment comprising the stalk region, the transmembrane domain, and the intracellular domain of the vaccinia virus extracellular enveloped virus (EEV)-specific membrane protein A (b) introducing one or more polynucleotides, each encoding an immunoglobulin light chain, into the population of host cells; wherein a heavy chain fusion protein and an immunoglobulin light chain expressed in the population of host cells are capable of combining within a host cell to form an antigen-binding domain of an immunoglobulin molecule that can be expressed on the surface of an EEV; (c) permitting release of EEV from the host cells; (d) contacting the released EEV with an antigen; and (e) recovering the polynucleotides of the first library from EEV that bind to the antigen.