Immunoglobulins devoid of light chains

Abstract

There is provided an isolated immunoglobulin comprising two heavy polypeptide chains sufficient for the formation of a complete antigen binding site or several antigen binding sites, wherein the immunoglobulin is further devoid of light polypeptide chains.

1 . A ligand comprising a single variable domain, wherein the single variable domain specifically binds to an antigen, and the variable domain comprises an affinity of an immunoglobulin that has undergone affinity maturation in vivo. 
     
     
         2 . The ligand of  claim 1 , wherein the antigen is selected from the group consisting of human protein, animal protein, determined antigens, antigens of pathological agents, bacteria, viruses, parasites, envelope glycoproteins of viruses, protein, hapten, carbohydrate, nucleic acid, galactosyl β-1-3-galactose epitope, myeloma immunoglobulin epitope, insect gut antigen, CD4 cells. 
     
     
         3 . A dual specific ligand comprising a first single variable domain and a second a single variable domain where at least one of the first single variable domain and the second single variable domain comprises an affinity of an immunoglobulin that has undergone affinity maturation in vivo. 
     
     
         4 . The dual specific ligand of  claim 3 , wherein said first single variable domain specifically binds to an antigen selected from the group consisting of, human, protein, animal protein, determined antigens, antigens of pathological agents, bacteria, viruses, parasites, envelope glycoproteins of viruses, protein, hapten, carbohydrate, nucleic acid, galactosyl α-1-3-galactose epitope, myeloma immunoglobulin epitope, insect gut antigen, CD4 cells; and wherein said second single variable domain specifically binds to an antigen selected from the group consisting of, human, protein, animal protein, determined antigens, antigens of pathological agents, bacteria, viruses, parasites, envelope glycoproteins of viruses, protein, hapten, carbohydrate, nucleic acid, galactosyl α-1-3-galactose epitope, myeloma immunoglobulin epitope, insect gut antigen, CD4 cells. 
     
     
         5 . A dual specific ligand comprising a first single variable domain and a second single variable domain, wherein the first single variable domain specifically binds to an antigen and the second single variable domain specifically binds to an antigen, wherein at least one of the first single variable domain and the second single variable domain comprises an affinity of an immunoglobulin that has undergone affinity maturation in vivo. 
     
     
         6 . The dual specific ligand of  claim 5 , wherein said first single variable domain specifically binds to an antigen selected from the group consisting of human protein, animal protein, determined antigens, antigens of pathological agents, bacteria, viruses, parasites, envelope glycoproteins of viruses, protein, hapten, carbohydrate, nucleic acid, galactosyl α-1-3-galactose epitope, myeloma immunoglobulin epitope, insect gut antigen, CD4 cells; and wherein said second single variable domain specifically binds to an antigen selected from the group consisting of human protein, animal protein, determined antigens, antigens of pathological agents, bacteria, viruses, parasites, envelope glycoproteins of viruses, protein, hapten, carbohydrate, nucleic acid, galactosyl α-1-3-galactose epitope, myeloma immunoglobulin epitope, insect gut antigen, CD4 cells.