title: Galactosyl-knock-out engineered pig as a xenogenic donor source of adipose MSCs for bone regeneration.
abstract: Pig adipose mesenchymal stem cells (AMSCs) could be proposed for the improvement of bone substitute. However, these xenogenic cells retain a galactosyl (Gal) epitope that elicits xenorejection. Our work aims to use Gal-Knock-Out (Gal-KO) pig AMSCs to associate cellular immunomodulation, humoral down-elicitation of Gal-KO cells and osteogenic capacity of AMSCs. Human and pig AMSCs were compared for proliferation/differentiation kinetics and bone neoformation in vivo. Humoral reaction against pig Gal+ vs. Gal-KO AMSCs and immunomodulation properties of Gal+ vs. Gal-KO AMSCs were assessed in vitro. Humoral/cellular reactions against Gal+ vs. Gal-KO osteogenic differentiated pig AMSC xenografts were assessed in an immunocompetent rodent model. Expansion/differentiation/bone neoformation was significantly improved with differentiated pig AMSCs compared with human cells. Based on immunohistochemistry and cell-based ELISA, Gal+ AMSCs had higher sensitivity to preformed/induced anti-pig antibodies than Gal-KO AMSCs. In vitro cellular immunomodulation was similar between Gal+ and Gal-KO AMSCs. In vivo, a significant reduction of anti-pig IgG was found at 1 month in rats implanted with Gal-KO AMSCs compared with those implanted with Gal+ AMSCs. Lymphocyte/macrophage infiltration of osteogenic differentiated pig AMSC xenografts was significantly lower at post-operative day (POD) 7 in recipients of Gal-KO vs. Gal+ pig cells. No significant difference was found at POD 28. The combination of the cellular immunomodulation with the Gal-KO phenotype of AMSCs can significantly improve the cellular engraftment of pig osteogenic cells by delaying xenorejection.
authors: Endocrine Cell Therapy Unit, Center of Tissue and Cell Therapy, Cliniques Universitaires Saint-Luc, Université catholique de Louvain, 1200 Brussels, Belgium.
authors: Thomas
authors: T
authors: Schubert
authors: Hervé
authors: H
authors: Poilvache
authors: Cesare
authors: C
authors: Galli
authors: Pierre
authors: P
authors: Gianello
authors: Denis
authors: D
authors: Dufrane
mesh_terms: D000273:Adipose Tissue / Q000166:cytology*; D000818:Animals; D000941:Antigens / Q000276:immunology; D001861:Bone Regeneration; D002454:Cell Differentiation; D049109:Cell Proliferation; D004797:Enzyme-Linked Immunosorbent Assay; D000939:Epitopes / Q000378:metabolism; D005690:Galactose / Q000276:immunology / Q000378:metabolism*; D055786:Gene Knockout Techniques; D006801:Humans; D056724:Immunity, Humoral / Q000276:immunology; D007114:Immunization; D007150:Immunohistochemistry; D056747:Immunomodulation / Q000276:immunology; D007700:Kinetics; D007959:Lymphocyte Culture Test, Mixed; D059630:Mesenchymal Stem Cells / Q000166:cytology* / Q000378:metabolism; D023421:Models, Animal; D010012:Osteogenesis; D011323:Primates / Q000276:immunology; D051381:Rats; D017208:Rats, Wistar; D034421:Sus scrofa; D014183:Transplantation, Heterologous
chemical_list: D000941:Antigens; D000939:Epitopes; D005690:Galactose