Antigen binding domains

Abstract

A process for the production of an antigen specific antigen binding domain using a transformed host containing an expressible DNA sequence encoding the antigen specific antigen binding domain, wherein the antigen specific antigen binding domain is derived from a variable region of the immunoglobulin isotype NAR found in fish.

1 . A process for the production of an antigen specific antigen binding domain using a transformed host containing an expressible DNA sequence encoding the antigen specific antigen binding domain, wherein the antigen specific antigen binding domain is derived from a variable region of the immunoglobulin isotype NAR found in a species of Elasmobranchii subclass.  
     
     
         2 . A process according to  claim 1  wherein the transformed host is a prokaryote or a lower eukaryote.  
     
     
         3 . A process according to  claim 2  wherein the prokaryote host is  Escherichia coli.    
     
     
         4 . A process according to  claim 1  wherein the expressible DNA sequence is in the form of a phagemid vector.  
     
     
         5 . A process according to  claim 1  wherein the species of Elasmobranchii subclass is a shark or a dog fish.  
     
     
         6 . A process according to  claim 5  wherein the shark is a nurse shark.  
     
     
         7 . A process according to  claim 1  wherein the antigen specific antigen binding domain has a specific specificity.  
     
     
         8 . A process according to  claim 1  wherein the antigen specific antigen binding domain is monoclonal.  
     
     
         9 . A process according to  claim 7  wherein the specificity of the antigen specific antigen binding domain is determined by an antigen which is introduced into the chosen fish.  
     
     
         10 . A process for the production of an antigen specific antigen binding domain comprising the steps of: 
 a) immunising a member of the Elasmobranchii subclass with an antigen;    b) isolating lymphocytes from the member;    c) isolating RNA from the lymphocytes;    d) amplifying DNA sequences encoding the antigen specific antigen binding domain by PCR;    e) cloning the amplified DNA into a display vector;    f) transforming a host to produce a library;    g) selecting the desired clones from the library;    h) isolating and purifying the antigen specific antigen binding domain from these clones;    i) cloning the DNA sequences encoding the antigen specific antigen binding domain into an expression vector;    j) transforming a host to allow expression of the expression vector.    
     
     
         11 . A process according to  claim 10  wherein before step d) the cDNA of the antigen specific antigen binding domain is generated.  
     
     
         12 . A process according to  claim 10  wherein restriction enzymes are used to digest the amplified DNA sequences encoding the antigen specific antigen binding domain.  
     
     
         13 . A process according to  claim 12  wherein the restriction enzymes are NcoI and NotI.  
     
     
         14 . A process according to  claim 10  wherein the display vector is any phagemid vector.  
     
     
         15 . A process according to  claim 14  wherein the display vector is pHEN2.  
     
     
         16 . A process according to  claim 10  wherein the expression vector is a soluble expression vector.  
     
     
         17 . A process according to  claim 16  wherein the soluble expression vector is pIMS100.  
     
     
         18 . An antigen specific antigen binding domain produced by the process in  claim 1 .  
     
     
         19 . A composition for the inhibition of protein activity comprising antigen specific antigen binding domains derived from a variable region of the immunoglobulin isotype NAR found in a species of Elasmobranchii subclass.  
     
     
         20 . A composition according to  claim 19 , wherein the antigen specific antigen binding domain is produced by the process in  claim 1 .  
     
     
         21 . A composition according to  claim 19  whereby inhibition of protein activity is in a concentration dependent manner.  
     
     
         22 . A composition according to  claim 19 , contained in a pharmaceutical carrier or diluent therefor.  
     
     
         23 . An antigen specific antigen binding domain produced from a variable region of NAR.