Engineered high-affinity human t cell receptors

Abstract

T cell receptors (TCRs) that have higher affinity for the Survivin antigen are provided. The high affinity TCRs were engineered through the generation of mutational libraries of TCRs in a single-chain format, followed by selection for improved stability and affinity on the surface of yeast (i.e. directed evolution). In embodiments, the engineered TCRs can be used in soluble form for targeted delivery in vivo, or as genes introduced into T cells in an adoptive T cell setting.

1 . A modified T cell receptor, or antigen-binding fragment thereof, comprising a Vα and a Vβ derived from a wild type T cell receptor, wherein the Vα or the Vβ, or both, comprise a mutation in one or more complementarity determining regions (CDRs) relative to the wild type T cell receptor, wherein the modified T cell receptor binds to a complex of the peptide Survivin and the HLA-A2 molecule with a nanomolar or higher affinity (K D  value of less than 10 −6 M). 
     
     
         2 . The modified T cell receptor of  claim 1 , wherein the modified T cell receptor comprises the Vα amino acid sequence set forth in SEQ ID NO:1. 
     
     
         3 . The modified T cell receptor of  claim 1 , wherein the modified T cell receptor comprises the Vα amino acid sequence set forth in SEQ ID NO:2. 
     
     
         4 . The modified T cell receptor of  claim 1 , wherein the modified T cell receptor comprises the single-chain T cell receptor with the amino acid sequence set forth in SEQ ID NO:3. 
     
     
         5 . The modified T cell receptor of  claim 1 , wherein the modified T cell receptor comprises the single-chain T cell receptor with the amino acid sequence set forth in SEQ ID NO:4. 
     
     
         6 . The modified T cell receptor of  claim 1 , comprising a modified Vα comprising an amino acid sequence having at least 80% identity to the Vα amino acid sequence set forth in SEQ ID NO:1. 
     
     
         7 . The modified T cell receptor of  claim 1 , comprising a modified Vα comprising an amino acid sequence having at least 80% identity to the Vα amino acid sequence set forth in SEQ ID NO:2. 
     
     
         8 . The modified T cell receptor of  claim 2 , wherein the modified T cell receptor comprises an amino acid substitution at one or more of CDR3α 92, CDR3α 100, CDR3α 101, CDR3α 102, and CDR3α 103. 
     
     
         9 . The modified T cell receptor of  claim 2 , wherein the modified T cell receptor comprises one or more of the following amino acid mutations: TCR Vα chain mutations N92S, N100K, A101G, R102Y, and L103K. 
     
     
         10 . The modified T cell receptor of  claim 3 , wherein the modified T cell receptor comprises one or more of the following amino acid mutations: TCR Vα chain mutations N92H, N100G, A101W, R102Y, and L103T. 
     
     
         11 . The modified T cell receptor of  claim 2  that is in soluble form. 
     
     
         12 . A therapeutic agent that targets cancer cells that express the survivin antigen, wherein the therapeutic agent comprises the modified T cell receptor of  claim 11 . 
     
     
         13 . A therapeutic agent that targets cancer cells that express the survivin antigen, wherein the therapeutic agent comprises a human T cell that expresses the modified T cell receptor of  claim 2 . 
     
     
         14 . The modified T cell receptor of  claim 3  that is in soluble form. 
     
     
         15 . A therapeutic agent that targets cancer cells that express the survivin antigen, wherein the therapeutic agent comprises the modified T cell receptor of  claim 14 . 
     
     
         16 . A therapeutic agent that targets cancer cells that express the survivin antigen, wherein the therapeutic agent comprises a human T cell that expresses the modified T cell receptor of  claim 3 . 
     
     
         17 . A method of treating a subject having a cancer that expresses the survivin antigen comprising administering the therapeutic agent of  claim 12 .