A local drug delivery system prolongs graft survival by dampening T cell infiltration and neutrophil extracellular trap formation in vascularized composite allografts

作者：Isabel Arenas Hoyos, Anja Helmer, Anaïs Yerly, Ioana Leşe, Stefanie Hirsiger, Lei Zhang, Daniela Casoni, Luisana Garcia, Mariafrancesca Petrucci, Sabine E. Hammer, Tereza Duckova, Yara Banz, Matteo Montani, Mihai A. Constantinescu, Esther Vögelin, Gregor Bordon, Simone Aleandri, Jean‐Christophe Prost, Adriano Taddeo, Paola Luciani, Robert Rieben, Nicoletta Sorvillo, Radu Olariu · 发表于：Frontiers in Immunology · 年份：2024 · DOI：10.3389/fimmu.2024.1387945 · 被引用次数：9 · 研究领域：Neutrophil, Myeloperoxidase and Oxidative Mechanisms、Organ and Tissue Transplantation Research、Transplantation: Methods and Outcomes

Introduction The standard treatment for preventing rejection in vascularized composite allotransplantation (VCA) currently relies on systemic immunosuppression, which exposes the host to well-known side effects. Locally administered immunosuppression strategies have shown promising results to bypass this hurdle. Nevertheless, their progress has been slow, partially attributed to a limited understanding of the essential mechanisms underlying graft rejection. Recent discoveries highlight the crucial involvement of innate immune components, such as neutrophil extracellular traps (NETs), in organ transplantation. Here we aimed to prolong graft survival through a tacrolimus-based drug delivery system and to understand the role of NETs in VCA graft rejection. Methods To prevent off-target toxicity and promote graft survival, we tested a locally administered tacrolimus-loaded on-demand drug delivery system (TGMS-TAC) in a multiple MHC-mismatched porcine VCA model. Off-target toxicity was assessed in tissue and blood. Graft rejection was evaluated macroscopically while the complement system, T cells, neutrophils and NETs were analyzed in graft tissues by immunofluorescence and/or western blot. Plasmatic levels of inflammatory cytokines were measured using a Luminex magnetic-bead porcine panel, and NETs were measured in plasma and tissue using DNA-MPO ELISA. Lastly, to evaluate the effect of tacrolimus on NET formation, NETs were induced in-vitro in porcine and human peripheral neutro...