Genetic Modifications And Target Genes In Porcine Organs For Xenotransplantation: A Systematic Review
DOI:
https://doi.org/10.62954/1ck0q355Keywords:
Xenotransplantation, Genetic editing, CRISPR-Cas9, Porcine organs, Immunogenic genes, TransgenesisAbstract
The growing demand for viable organs for transplantation has surpassed the available supply, leading to a global healthcare crisis. In this context, pig-to-human xenotransplantation has emerged as a promising alternative, although it still faces significant immunological barriers. This review aimed to identify the most relevant genetic modifications applied to porcine organs intended for xenotransplantation, with a focus on studies published between 2022 and 2025. A systematic review was conducted following the PRISMA 2020 guidelines. Searches were performed in databases such as PubMed, SpringerLink, and ScienceDirect. A total of 12 studies that met the inclusion criteria were selected. The most frequent genetic modifications involved the knockout of immunogenic genes such as GGTA1, CMAH, and B4GALNT2, and the insertion of human transgenes like CD46, CD55, hTBM, and CD47, using techniques such as CRISPR/Cas9 and somatic cell nuclear transfer. Successful kidney, heart, and liver xenotransplantations were reported in both deceased and living human recipients, with graft function durations ranging from 2 to 49 days and no evidence of hyperacute rejection. Nevertheless, challenges such as viral reactivation and chronic rejection remain. Genetic engineering of porcine organs has led to significant progress toward the clinical viability of xenotransplantation. However, long-term studies addressing immunological, ethical, and biosafety concerns are still needed.
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