A genetically reprogrammed, biologically active and metabolically active cell, tissue, and/or an organ comprising live cells that vascularize after xenotransplantation, wherein the genetically reprogrammed, biologically active and metabolically active cell, tissue, and/or an organ has been obtained from a non-wild type, biologically engineered porcine comprising a nuclear genome that has been reprogrammed to replace a plurality of nucleotides in a plurality of exon regions of a major histocompatibility complex of a wild-type porcine with a plurality of synthesized nucleotides from a human captured reference sequence, and
- wherein cells of said genetically reprogrammed porcine do not present one or more surface glycan epitopes selected from alpha-Gal, Neu5Gc, and SDa,
- wherein genes encoding alpha-1,3 galactosyltransferase, cytidine monophosphate-N-acetylneuraminic acid hydroxylase (CMAH), and β1,4-N-acetylgalactosaminyltransferase are altered such that the genetically reprogrammed porcine lacks functional expression of surface glycan epitopes encoded by said genes,
- wherein the genetically reprogrammed porcine's genome comprises endogenous exon and/or intron regions of the wild-type porcine's Major Histocompatibility Complex corresponding to exon regions of SLA-1, SLA-2, SLA-3, SLA-6, SLA-7, SLA-8, SLA-DRA, SLA-DRB, SLA-DQA, and/or SLA-DQB, and any combination thereof, that have been substituted with nucleotides from orthologous exons of a known human HLA-A, HLA-B, HLA-C, HLA-E, HLA-F, HLA-G, HLA-DRA, HLA-DRB, HLA-DQA, and/or HLA-DQB sequence of the human captured reference sequence,
- wherein intron regions of the wild-type porcine's genome are not reprogrammed, and
- wherein the reprogrammed genome comprises at least one of A-D:
- A) wherein the reprogrammed porcine nuclear genome comprises site-directed mutagenic substitutions of nucleotides at exon regions of the wild-type porcine's β2-microglobulin with nucleotides from orthologous exons of a known human β2-microglobulin from the human captured reference sequence;
- B) wherein the reprogrammed porcine nuclear genome comprises a polynucleotide that encodes a polypeptide that is a humanized beta 2 microglobulin (hB2M) polypeptide sequence that is at least 95% identical to the amino acid sequence of beta 2 microglobulin glycoprotein expressed by the human captured reference genome;
- C) wherein the reprogrammed porcine nuclear genome has been reprogrammed such that, at the porcine's endogenous β2-microglobulin locus, the nuclear genome has been reprogrammed to comprise a nucleotide sequence encoding β2-microglobulin polypeptide of the human recipient;
- D) wherein the genetically reprogrammed porcine's genome comprises endogenous exon and/or intron regions of the wild-type porcine's B2M, PD-L1, CTLA-4, EPCR, TBM, TFPI, and/or MIC-2, and any combination thereof, that have been substituted with nucleotides from orthologous exons of a known human B2M, PD-L1, CTLA-4, EPCR, TBM, TFPI, and MIC-2 sequence,
- wherein the reprogrammed porcine nuclear genome has been reprogrammed such that the genetically reprogrammed porcine lacks functional expression of the wild-type porcine's endogenous β2-microglobulin polypeptides, and
- wherein said genetically reprogrammed porcine is free of at least the following pathogens:
- (i) Ascaris species, cryptosporidium species, Echinococcus, Strongyloids sterocolis, and Toxoplasma gondii in fecal matter;
- (ii) Leptospira species, Mycoplasma hyopneumoniae, porcine reproductive and respiratory syndrome virus (PRRSV), pseudorabies, transmissible gastroenteritis virus (TGE)/Porcine Respiratory Coronavirus, and Toxoplasma Gondii by determining antibody titers;
- (iii) Porcine Influenza;
- (iv) the following bacterial pathogens as determined by bacterial culture:
- Bordetella bronchisceptica, Coagulase-positive staphylococci, Coagulase-negative staphylococci, Livestock-associated methicillin resistant Staphylococcus aureus (LA MRSA), Microphyton and Trichophyton spp.;
- (v) Porcine cytomegalovirus;
- and
- (vi) Brucella suis.