HLA G-modified cells and methods
Disclosed herein are genetically modified cells expressing HLA-G (e.g., cell surface HLA-G) persistently, and nucleic acid compositions useful for generating such genetically modified cells. Also disclosed are cell therapy methods that utilize genetically modified cells that express HLA-G persistently. The HLA-G genetic modifications described herein provide the cells with characteristics of reduced immunogenicity and/or improved immunosuppression, such that these cells have the promise of being universal or improved donor cells for transplants, cellular and tissue regeneration or reconstruction, and other therapies.
1. A genetically modified mammalian cell that has reduced immunogenicity and/or improved immunosuppression as compared to the mammalian cell without said genetic modification, wherein
the genetically modified mammalian cell comprises in its genome an exogenous nucleic acid comprising: (a) a nucleic acid sequence encoding a Human leukocyte antigen-G (HLA-G) protein comprising a full length amino acid sequence of SEQ ID NO:2 operably linked to an Elongation Factor-1 alpha (EF-1α) promoter comprising the sequence of SEQ ID NO:6; and (b) a 3′ untranslated region (UTR) comprising a full length nucleotide sequence of SEQ ID NO:3; wherein
the genetically modified mammalian cell is selected from the group consisting of embryonic stem cell, embryonic epidermal progenitors and human dermal fibroblast cells, and wherein the encoded HLA-G protein is expressed by the genetically modified mammalian cell for at least seven weeks.
2. The genetically modified mammalian cell of claim 1 , wherein the HLA-G protein is expressed for at least 20 weeks.
3. The genetically modified mammalian cell of claim 2 , wherein the HLA-G protein is expressed for at least 50 weeks.
4. The genetically modified mammalian cell of claim 1 , wherein the expressed HLA-G is present on the cell surface of the genetically modified mammalian cell.
5. The genetically modified mammalian cell of claim 1 , wherein the modified mammalian cell is a human cell.
6. The genetically modified mammalian cell of claim 1 , wherein the genetically modified cell is selected from the group consisting of a human embryonic stem cell, a human mesenchymal stem cell, a human embryonic epidermal progenitor cell, and a human dermal fibroblast.
7. The genetically modified mammalian cell of claim 1 , wherein the reduced immunogenicity and/or improved immunosuppression of the genetically modified cell as compared to the mammalian cell without said genetic modification is determined by either: (1) a reduction of natural killer cell, NK-92 cytotoxicity of the genetically modified cell as compared to the mammalian cell without said genetic modification, (2) a reduction of in vitro peripheral blood mononuclear cell proliferation of the genetically modified cell as compared to the mammalian cell without said genetic modification, and (3) an increase in the size and weight of tumor formation by the genetically modified cell as compared to the mammalian cell without said genetic modification in humanized NOD scid gamma, NSG mice.
8. An artificial tissue comprising the genetically modified mammalian cell of claim 1 .
9. A skin graft, skin-repair, or skin-regeneration composition comprising the genetically modified mammalian cell of claim 6 .
10. The genetically modified mammalian cell of claim 1 , wherein the exogenous nucleic acid is an expression vector.
11. The genetically modified mammalian cell of claim 10 , wherein the expression vector is a transposon vector.
12. The genetically modified mammalian cell of claim 10 , wherein the vector further comprises a nucleic acid sequence encoding a reporter protein.