Pancreatic islets of transgenic LEA29Y animals for treating diabetes

Abstract

The present invention relates to methods of treating diabetes in a human subject comprising the use of pancreatic islets or of embryonic pancreatic tissue of a transgenic animal, wherein said transgenic animal contains a polynucleotide sequence encoding a CTLA4 peptide-immunoglobulin fusion, preferably LEA29Y, and expresses said CTLA4 peptide-immunoglobulin fusion in a tissue-specific manner in pancreatic islets.

1 . A method of treating diabetes in a human subject, comprising the steps of:
 isolating pancreatic islets of a transgenic animal and administering said isolated pancreatic islets of the transgenic animal into a human subject in need thereof, wherein said transgenic animal is a transgenic animal whose genome comprises a recombinant nucleic acid comprising a polynucleotide sequence encoding a CTLA4 peptide fused to an immunoglobulin (“CTLA4 peptide-immunoglobulin fusion”) wherein said polynucleotide sequence is operably linked to an insulin promoter that results in expression of the CTLA4 peptide-immunoglobulin fusion, wherein said animal expresses the CTLA4 peptide-immunoglobulin fusion,   and wherein said animal exhibits, as a result of the expression of said CTLA4 peptide-immunoglobulin fusion, tissue-specific expression of the CTLA4 peptide-immunoglobulin fusion in pancreatic islets.   
     
     
         2 . The method of  claim 1 , wherein the transgenic animal does not exhibit an immunodeficient phenotype. 
     
     
         3 . The method of  claim 1 , wherein the recombinant nucleic acid is an expression construct, a plasmid or viral vector. 
     
     
         4 . The method of  claim 3 , wherein the insulin promoter is pig INS promoter, rat insulin 2 gene promoter (RIPII), or PDX1 promoter. 
     
     
         5 . The method of  claim 1 , wherein the recombinant nucleic acid encodes the CTLA4 peptide-immunoglobulin fusion that is LEA29Y. 
     
     
         6 . The method of  claim 1 , wherein the recombinant nucleic acid encodes a protein comprising the sequence of SEQ ID NO. 1. 
     
     
         7 . The method of  claim 1 , wherein the transgenic animal contains the recombinant nucleic acid in its germ cells and somatic cells. 
     
     
         8 . The method of  claim 1 , wherein LEA29Y is expressed in the pancreatic islets. 
     
     
         9 . The method of  claim 1 , wherein the transgenic pancreatic islets of said animal display the same potential to normalize glucose homeostasis as wild type cells. 
     
     
         10 . The method of  claim 1 , wherein the transgenic pancreatic islets are administered to the human subject by xenotransplantation. 
     
     
         11 . The method of  claim 1 , wherein after xenotransplantation of said transgenic pancreatic islets of said animal into a human subject, said transgenic pancreatic islets are protected from rejection by the host immune system. 
     
     
         12 . The method of  claim 1 , wherein the human subject requires less administration of immunosuppressive agents compared to standard therapy and/or compared to (xeno)transplantation of wild type pancreatic islets of an animal. 
     
     
         13 . The method of  claim 1 , wherein the transgenic animal is a pig, bovine, or small ruminant. 
     
     
         14 . The method of  claim 1 , wherein the diabetes treated is diabetes type 1 and/or diabetes type 2. 
     
     
         15 . The method of  claim 1 , wherein the transgenic pancreatic islets are encapsulated or micro-encapsulated before administration. 
     
     
         16 . The method of  claim 15 , wherein the encapsulated or micro-encapsulated transgenic pancreatic islets are administered by implementation. 
     
     
         17 . A method of treating diabetes in a human subject, comprising the steps of isolating transgenic embryonic pancreas or transgenic embryonic pancreatic tissue of a transgenic animal and administering said isolated transgenic embryonic pancreas or said isolated transgenic embryonic pancreatic tissue of the transgenic animal into a human subject in need thereof,
 wherein said transgenic animal is a transgenic animal whose genome comprises a recombinant nucleic acid comprising a polynucleotide sequence encoding a CTLA4 peptide fused to an immunoglobulin (“CTLA4 peptide-immunoglobulin fusion”) wherein said polynucleotide sequence is operably linked to an insulin promoter that results in expression of the CTLA4 peptide-immunoglobulin fusion, wherein said animal expresses the CTLA4 peptide-immunoglobulin fusion,   and wherein said animal exhibits, as a result of the expression of said CTLA4 peptide-immunoglobulin fusion, tissue-specific expression of the CTLA4 peptide-immunoglobulin fusion in the transgenic embryonic pancreas or transgenic embryonic pancreatic tissue.   
     
     
         18 . The method of  claim 17 , wherein tissue-specific expression of the CTLA4 peptide-immunoglobulin fusion occurs in pancreatic islets of xenogeneic tissue that is administered to the subject. 
     
     
         19 . The method of  claim 17 , wherein the transgenic animal does not exhibit an immunodeficient phenotype. 
     
     
         20 . The method of  claim 17 , wherein the recombinant nucleic acid is an expression construct, a plasmid or viral vector. 
     
     
         21 . The method of  claim 17 , wherein the insulin promoter is pig INS promoter, rat insulin 2 gene promoter (RIPII), or PDX1 promoter. 
     
     
         22 . The method of  claim 17 , wherein the recombinant nucleic acid encodes the CTLA4 peptide-immunoglobulin fusion that is LEA29Y. 
     
     
         23 . The method of  claim 22 , wherein the recombinant nucleic acid encodes a protein comprising the sequence of SEQ ID NO. 1. 
     
     
         24 . The method of  claim 17 , wherein the transgenic animal contains the recombinant nucleic acid in its germ cells and somatic cells. 
     
     
         25 . The method of  claim 17 , wherein LEA29Y is expressed in the embryonic pancreas or embryonic pancreatic tissue of the transgenic animal and in the pancreatic islets of the tissue administered to the subject. 
     
     
         26 . The method of  claim 17 , wherein the transgenic pancreatic islets of said animal display the same potential to normalize glucose homeostasis as wild type cells. 
     
     
         27 . The method of  claim 17 , wherein the isolated embryonic pancreas or embryonic pancreatic tissue are administered to the human subject by xenotransplantation. 
     
     
         28 . The method of  claim 17 , wherein the transgenic embryonic pancreas or embryonic pancreatic tissue grows at a transplantation site of the subject. 
     
     
         29 . The method of  claim 17 , wherein after administration of said transgenic embryonic pancreas or transgenic embryonic pancreatic tissue of said animal into a human subject or into a humanized animal model, said transgenic embryonic pancreas or transgenic embryonic pancreatic tissue is protected from rejection by the host immune system. 
     
     
         30 . The method of  claim 17 , wherein the subject requires less administration of immunosuppressive agents compared to standard therapy and/or compared to (xeno)transplantation of wild type pancreatic islets of an animal. 
     
     
         31 . The method of  claim 17 , wherein the transgenic animal is a pig, bovine, or small ruminant. 
     
     
         32 . The method of  claim 17 , wherein the diabetes treated is diabetes type 1 and/or diabetes type 2.