Identification and display of peptide ligands

Abstract

A carrier to which is attached a peptide and DNA encoding the peptide, wherein the peptide includes at least one non-natural amino acid and/or wherein the peptide has a constrained secondary structure; or a carrier to which is attached β2 microglobulin, a peptide, and DNA encoding the peptide, said carrier not bearing an MHC or MHC-like molecule.

1 . A carrier to which is attached a peptide and DNA encoding the peptide, wherein the peptide includes at least one non-natural amino acid and/or wherein the peptide has a constrained secondary structure. 
     
     
         2 . The carrier of  claim 1  wherein the peptide's secondary structure is constrained by at least one internal linkage between at least two amino acids of the peptide or wherein the peptide's secondary structure is constrained by binding to a scaffold molecule. 
     
     
         3 . (canceled) 
     
     
         4 . The carrier of  claim 1 , wherein β2 microglobulin is attached to the peptide. 
     
     
         5 . A carrier to which is attached β2 microglobulin, a peptide, and DNA encoding the peptide, said carrier not bearing an MHC or MHC-like molecule. 
     
     
         6 . The carrier of  claim 5 , further comprising a flexible linker attached to the peptide. 
     
     
         7 . The carrier of  claim 6  wherein the flexible linker is selected from the group consisting of β2 microglobulin, a His tag, a hapten, an epitope, a binding fragment of an antibody or a member of a binding pair. 
     
     
         8 . The carrier of  claim 5 , wherein the β2 microglobulin is attached to the peptide as part of a β2 microglobulin-peptide fusion, and the DNA encodes the β2 microglobulin-peptide fusion. 
     
     
         9 . The carrier of  claim 8  wherein the peptide is fused to the N-terminus, C-terminus, or an internal site of the β2 microglobulin. 
     
     
         10 . (canceled) 
     
     
         11 . (canceled) 
     
     
         12 . The carrier of  claim 8 , wherein the peptide is fused at a position between about amino acids 10 and 20, and/or 70 and 78, and/or 30 and 35, and/or 83 and 91 of the β2 microglobulin. 
     
     
         13 . The carrier of  claim 8 , wherein said peptide or β2 microglobulin-peptide fusion is attached to the carrier via an interaction between members of a binding pair of molecules, one of the members of the binding pair being attached to the peptide or fusion, and the second member of the binding pair being attached directly or indirectly to the carrier. 
     
     
         14 . (canceled) 
     
     
         15 . The carrier of  claim 13 , wherein the binding pair of molecules is streptavidin and a streptavidin binding protein. 
     
     
         16 . The carrier of  claim 15 , wherein the streptavidin binding protein is attached to the peptide or β2 microglobulin-peptide fusion, and the streptavidin is attached to the carrier. 
     
     
         17 . (canceled) 
     
     
         18 . The carrier of  claim 13 , wherein the binding pair of molecules is an antibody or binding fragment thereof, and its antigen or hapten. 
     
     
         19 . The carrier of  claim 18 , wherein the antigen or hapten is attached to the peptide, β2 microglobulin-peptide fusion, or the carrier; and
 wherein the antibody or binding fragment thereof is attached to the carrier, peptide, or β2 microglobulin-peptide fusion. 
 
     
     
         20 . (canceled) 
     
     
         21 . (canceled) 
     
     
         22 . (canceled) 
     
     
         23 . The carrier of  claim 5 , wherein the carrier is multivalent. 
     
     
         24 . The carrier of  claim 5 , wherein the peptide is between about 4 and about 50 amino acids. 
     
     
         25 . The carrier of  claim 5 , the carrier being a solid support. 
     
     
         26 . The carrier of  claim 25 , wherein the solid support is a bead. 
     
     
         27 . A library containing a plurality of carriers of  claim 5 , wherein the library contains at least two different peptides borne on separate carriers. 
     
     
         28 . The library of  claim 27 , wherein the at least two different peptides includes a set of peptides in which at least one amino acid position is variable. 
     
     
         29 . The library of  claim 28 , wherein at least one non-natural amino acid or all natural amino acids are represented at the at least one variable amino acid position. 
     
     
         30 . (canceled) 
     
     
         31 . The library of  claim 28 , wherein at least 2, 3, 4, 5, 6, 7, 8, 9 or 10 amino acid positions of the peptide are variable. 
     
     
         32 . The library of  claim 28 , wherein all positions of the peptide are variable. 
     
     
         33 . (canceled) 
     
     
         34 . A method to identify a peptide ligand for a molecule, and/or the peptide ligand's encoding DNA, the method comprising providing the library of  claim 27 , and exposing the library to the molecule. 
     
     
         35 . The method of  claim 34  further comprising the step of recovering the peptide ligand and/or its encoding DNA, from a carrier which bound to the molecule. 
     
     
         36 . (canceled) 
     
     
         37 . (canceled) 
     
     
         38 . The method of  claim 34 , wherein a carrier which binds to the molecule is selected by binding to a solid support membrane, cell or lipid bilayer carrying the molecule.