Alpha (1,3) galactosyl transferase negative swine

Abstract

Transgenic swine in which the normal expression of α(1,3) galactosyltransferase is prevented in at least one organ of tissue type. The absence or inactivation of this enzyme prevents the production of carbohydrate moieties having the distinctive terminal Galα1-3Galβ1-4GlcNAc epitope that is a significant factor in xenogeneic, particularly human, transplant rejection of swine grafts.

What is claimed is:  
     
         1 . A transgenic swine is which the normal expression of the α(1,3) galactosyltransferase is prevented in at least one organ or tissue type.  
     
     
         2 . The transgenic swine of  claim 1  which has been made to produce a nucleic acid sequence that binds to and prevents the translation of mRNA coding for α(1,3) galactosyltransferase in said swine.  
     
     
         3 . The transgenic swine of  claim 2  whose genome had been modified to include a construct comprising a DNA encoding an antisense RNA to that portion of the α(1,3) galactosyltransferase coding region necessary to prevent or express a functional enzyme operably linked to a promoter therefore.  
     
     
         4 . The transgenic swine of  claim 3  wherein the promoter is a strong non-tissue specifiic constitutive or regulatable promoter.  
     
     
         5 . The transgenic swine of  claim 3  wherein the promoter is a strong tissue specific constitutive or regulatable promoter.  
     
     
         6 . The transgenic swine of  claim 1  which has been made to produce ribozyme.  
     
     
         7 . The transgenic swine of  claim 6  which has been modified to include a construct comprising DNA coding for at least that portion of a ribozyme necessary to inactivate α(1,3) galactosyltransferase operably linked to promoter therefor.  
     
     
         8 . The transgenic swine of  claim 7  wherein the promoter is a strong non-tissue specific constitutive or regulatable promoter.  
     
     
         9 . The transgenic swine of  claim 7  wherein the promoter is a strong tissue specific constitutive or regulatable promoter.  
     
     
         10 . An α(1,3) galactosyltransferase negative swine grown from a porcine oocyte whose pronuclear material has been removed and into which has been introduced a pluripotent porcine embryonic stemcell that is negative for the expression of α(1,3) galactosyltransferase  
     
     
         11 . A nucleic acid having a sequence selected from the group consisting of SEQ. ID. NOS. 1 and 13 through 24.  
     
     
         12 . The nucleic acid of  claim 11  having the sequence set forth in SEQ. ID. NO. 1.  
     
     
         13 . The nucleic acid of  claim 11  wherein the SEQ. ID. NOS. are selected from the group consisting of SEQ. ID. NOS. 13 through 15.  
     
     
         14 . The nucleic acid of  claim 11  wherein the SEQ. ID. NOS. are selected from the group consisting of SEQ. ID. NOS. 16 through 21.  
     
     
         15 . The nucleic acid of  claim 11  wherein the SEQ. ID. NOS. are selected from the group consisting of SEQ. ID. NOS. 22 through 24.  
     
     
         16 . The transgenic swine of  claim 1  in which the normal expression of the β (1,3) galactosyltransferese gene is prevented by introduction to said swine of an isogenic DNA-containing targeting vector.  
     
     
         17 . The α(1,3) galactosyltransferese negative swine of  claim 16  grown from a porcine zygote which has been modified by homologous recombination with an isogenic DNA targeting vector at the α(1,3) galactosyltransferese chromosomal locus.  
     
     
         18 . The α(1,3) galactosyltransferese negative swine of  claim 17  wherein the isogenic DNA targeting vector comprises at least about 6 kb of isogenic DNA and a promoterless selectable marker gene.