title: Heterelogous expression of mutated HLA-G decreases immunogenicity of human embryonic stem cells and their epidermal derivatives.
abstract: Human embryonic stem cells (hESCs) are capable of extensive self-renewal and expansion and can differentiate into any somatic tissue, making them useful for regenerative medicine applications. Allogeneic transplantation of hESC-derived tissues from results in immunological rejection absent adjunctive immunosuppression. The goal of our study was to generate a universal pluripotent stem cell source by nucleofecting a mutated human leukocyte antigen G (mHLA-G) gene into hESCs using the PiggyBac transposon. We successfully generated stable mHLA-G(EF1α)-hESC lines using chEF1α promoter system that stably expressed mHLA-G protein during prolonged undifferentiated proliferation andin differentiated embryoid bodies as well as teratomas. Morphology, karyotype, and telomerase activity of mHLA-G expressing hESC were normal. Immunofluorescence staining and flow cytometry analysis revealed persistent expression of pluripotent markers, OCT-3/4 and SSEA-4, in undifferentiated mHLA-G(EF1α)-hESC. Nucleofected hESC formed teratomas and when directed to differentiate into epidermal precursors, expressed high levels of mHLA-G and keratinocyte markers K14 and CD29. Natural killer cell cytotoxicity assays demonstrated a significant decrease in lysis of mHLA-G(EF1a)-hESC targets relative to control cells. Similar results were obtained with mHLA-G(EF1α)-hESC-derived epidermal progenitors (hEEP). One way mixed T lymphocyte reactions unveiled that mHLA-G(EF1a)-hESC and -hEEP restrained the proliferative activity of mixed T lymphocytes. We conclude that heterologous expression of mHLA-G decreases immunogenicity of hESCs and their epidermal differentiated derivatives.
authors.affiliation: Escape Therapeutics, Inc., San Jose, CA, USA.
authors.forename: Longmei
authors.initials: L
authors.lastname: Zhao
authors.affiliation: Escape Therapeutics, Inc., San Jose, CA, USA.
authors.forename: Takele
authors.initials: T
authors.lastname: Teklemariam
authors.affiliation: Escape Therapeutics, Inc., San Jose, CA, USA; Elixir Institute of Regenerative Medicine, Inc., San Jose, CA, USA. Electronic address: basil@escapetherapeutics.com.
authors.forename: Basil M
authors.initials: BM
authors.lastname: Hantash
mesh_terms: D000818:Animals; D015415:Biomarkers / Q000378:metabolism; D002454:Cell Differentiation; D049109:Cell Proliferation; D048430:Cell Shape; D002470:Cell Survival; D002478:Cells, Cultured; D003602:Cytotoxicity, Immunologic; D053595:Embryonic Stem Cells / Q000276:immunology* / Q000378:metabolism; D000078404:Epidermal Cells; D004817:Epidermis / Q000276:immunology* / Q000378:metabolism; D018507:Gene Expression Regulation, Developmental; D005838:Genotype; D059951:HLA-G Antigens / Q000235:genetics* / Q000276:immunology* / Q000378:metabolism; D006801:Humans; D007108:Immune Tolerance; D053631:Interleukin Receptor Common gamma Subunit / Q000172:deficiency / Q000235:genetics; D059785:Karyotype; D007694:Killer Cells, Natural / Q000276:immunology; D016688:Mice, Inbred NOD; D018345:Mice, Knockout; D016513:Mice, SCID; D009154:Mutation; D009419:Nerve Tissue Proteins / Q000235:genetics / Q000378:metabolism; D020648:Peptide Elongation Factor 1 / Q000235:genetics; D010641:Phenotype; D039904:Pluripotent Stem Cells / Q000276:immunology* / Q000378:metabolism; D011401:Promoter Regions, Genetic; D019098:Telomerase / Q000378:metabolism; D013724:Teratoma / Q000235:genetics / Q000276:immunology / Q000378:metabolism; D014162:Transfection
chemical_list: D015415:Biomarkers; D059951:HLA-G Antigens; C507942:Il2rg protein, mouse; D053631:Interleukin Receptor Common gamma Subunit; D009419:Nerve Tissue Proteins; C569369:PGBD1 protein, human; D020648:Peptide Elongation Factor 1; D019098:Telomerase