Universal stem cells

Abstract

The subject invention pertains to materials and methods for preparing multi-potential stem cells having a pre-selected expression of MHC antigens. Stem cells of the subject invention can be used to generate histocompatible tissues/organs for transplantation. The process of the subject invention comprises the use of targeting vectors capable of gene knockout, insertion of site-specific recombination cassettes, and the replacement of histocompatibility alleles in the stem cell. Novel knockout vectors are used to delete designated regions of one chromosome. Recombination cassette vectors are then used to delete the same region on the second chromosome and deposit a site-specific recombination cassette which can be utilized by replacement vectors for inserting the new MHC genes on the chromosome of the engineered cell. The subject invention also pertains to cells, tissues, and transgenic mammal prepared using the methods and materials of the invention.

1 . A method for treating a condition selected from the group consisting of malignancy, autoimmune disease, genetic defects, and tissue rejection, said method comprising preparing tissue from a cell expressing at least one heterologous bistocompatibility allele and at least one therapeutic gene, wherein the expression of said therapeutic gene provides a therapeutic effect on said condition; and transplanting said tissue produced from said cell into a patient in need of such treatment.  
   
   
       2 . A method for treating a condition benefiting from transplantation of xenographic cells, consisting of preparing a collection of human pluripotent stem cells expressing at least one heterologous histocompatibility allele and optionally at least one therapeutic gene, wherein expression of said therapeutic gene provides a therapeutic effect on said condition upon administration of said collection of stem cells to a subject in need thereof.  
   
   
       3 . A method for treating a tissue rejection in a human subject in need thereof, comprising providing to said subject a composition of pluripotent stem cells lacking display of homologous MHC gene products, wherein said cells have integrated into at least one chromosome of the cell a heterologous MHC human gene allele selected to confer an immune response in a human heterologous subject when said subject is exposed to an immunogen.  
   
   
       4 . The method of  claim 2  or  3  wherein the heterologous MHC human gene allele is a class II MHC allele selected from HLA-DR1, HLA-DR2, HLA-DR3, HLA-DR4, HLA-DR7, HLA-DR8, HLA-DR9, HLA-DR11, HLA-DR12, HLA-DR13, HLA-DR14, HLA-DR15, HLA-DRBL or combinations thereof.  
   
   
       5 . The method of  claim 2  or  claim 3  wherein the heterologous MHC human gene allele is an HLA allele selected from the group consisting of HLA-B7, HLA-B8, HLA-B35, HLA-B52, HLA-B60, HLA-B44, HLA-B39, HLA-B48 and combinations thereof.  
   
   
       6 . The method of  claim 3  wherein the tissue is liver, heart, lung or bone marrow.  
   
   
       7 . The method of  claim 2  wherein said therapeutic effect is antibacterial, antiviral or antitumorigenic.  
   
   
       8 . A composition comprising a collection of pluripotent stem cells that lack display of homologous MHC gene products wherein said cells have integrated into at least one chromosome of the cell a heterologous MHC human gene allele selected to confer an immune response in a human heterologous host when said host is exposed to an immunogen.  
   
   
       9 . The composition of  claim 8  wherein said stem cells further comprise a therapeutic gene that expresses a therapeutic product.  
   
   
       10 . The composition of  claim 9  wherein the therapeutic product is an antibacterial, an antiviral or an anticancer agent.