Patent ID: 8445410
Filing Date: 2013-05-21
Classification: C07K,C12N,C40B,G01N

Abstract:
1. A method of screening nucleic acids, the method comprising: providing a first plurality of nucleic acid cassettes, each cassette encoding a first immunoglobulin or functional fragment thereof that is displayed on the surface of a prokaryotic cell, wherein each nucleic acid cassette comprises a first nucleic acid sequence encoding a first immunoglobulin variable domain, a second nucleic acid sequence encoding a second immunoglobulin variable domain, and a ribosomal binding site disposed between the first and second nucleic acid sequences, wherein the first and second nucleic acid sequences are in the same translational orientation and can be transcribed as a single transcript; selecting a subset of the first plurality by contacting the first immunoglobulin or functional fragment thereof encoded by the first plurality to a target and obtaining the subset encoding an immunoglobulin or functional fragment thereof that binds the target; reformatting in a vector for mammalian cell expression, each nucleic acid cassette of the subset such that each reformatted nucleic acid encodes a second immunoglobulin or functional fragment thereof that includes a first immunoglobulin variable domain, a second immunoglobulin variable domain, and an effector domain not encoded by the nucleic acids of the first plurality, wherein the first and second nucleic acid sequences are in the same translational orientation; introducing the reformatted nucleic acids into mammalian cells to form a plurality of expression cells that can produce the second immunoglobulin or functional fragment thereof that are encoded by the reformatted nucleic acids; and screening the expression cells to identify cells that produce at least a threshold amount of the second immunoglobulin or functional fragment thereof.