Binding Moieties Based On Shark IgNAR Domains

Abstract

The present invention relates to immunoglobulin new antigen receptors (IgNARs) from fish and uses thereof. In particular, the present invention relates to modified IgNAR variable domains and to domains from members of the immunoglobulin superfamily that have been modified to include structural features derived from IgNAR variable domains.

1 - 5 . (canceled) 
     
     
         6 . A method of altering a binding property of an I-set domain, said method comprising inserting a randomised loop into a region of said I-set domain wherein said region is equivalent to loop region 8 of an IgNAR variable domain. 
     
     
         7 . The method of  claim 6 , wherein said I-set domain is NCAM domain 1. 
     
     
         8 . The method of  claim 6 , in which amino acids of said I-set domain are equivalent to amino acids Lys32, Asp33, Thr34, Gly 35, Tyr55, Glu 57 and Thr58 of an IgNAR variable domain having SEQ ID NO:3 are modified. 
     
     
         9 . The method of  claim 6 , wherein said region equivalent to loop region 8 of said IgNAR variable domain comprises a portion of loop region 8 and a portion of a β-strand selected from the group consisting of β-strand F and β-strand G. 
     
     
         10 . The method of  claim 6 , wherein said randomised loop is selected from a library comprising a plurality of heterologous randomised loops. 
     
     
         11 . The method of  claim 6 , wherein said randomised loop comprises between approximately 5 to 50 amino acids. 
     
     
         12 . The method of  claim 10 , wherein said heterologous randomised loop ranges from between approximately 5 to 50 amino acids. 
     
     
         13 . The method of  claim 6 , wherein said randomised loop is a target molecule binding site. 
     
     
         14 . The method of  claim 6 , wherein said randomised loop is an antigen biding site.