Prolongation of graft survival via layer-by-layer assembly of collagen and immunosuppressive particles on pancreatic islets

Advances in the Use of Biologics and Biomaterials toward the Improvement of Pancreatic Islet Graft Survival in Type 1 Diabetes

“…Local delivery of immunosuppressants could circumvent systemic drug exposure and may allow for the use of lower doses to reduce β‐cell toxicity. [ 92 ] Recent examples of local immunomodulatory approaches include genetic modification of stem cell‐derived islets to produce IL‐10, TGF‐β, and IL‐2 cytokines in order to recruit regulatory T‐cells to the islet microenvironment. This resulted in improved islet graft survival and diabetes reversal up to 8‐weeks demonstrating the approach can promote immune tolerance of islets in vivo.…”

“…Furthermore, multilayer coatings can serve as a reservoir for controlled local delivery of immunosuppressant drugs, as demonstrated with the LbL deposition of collagen and microparticles containing tacrolimus (TAC) on rat islets. [ 92 ] Polydopamine‐coated PLGA microparticles loaded with tacrolimus (PD‐TAMP) and collagen were used for LbL coating of rat islets, which were later modified with an additional conformal alginate hydrogel layer to prevent premature particle detachment. Scanning electron microscopy images confirmed coating deposition (Figure 13B) and in vitro results indicated good viability and insulin secretion when compared to uncoated controls.…”

“…[146d] Copyright 2021, John Wiley and Sons Ltd. B) Scanning electron microscopy images of islets coated with collagen and PD-TAMP multilayers, C) histology image of coated islets 7 days post-transplantation with red arrows indicating coating, D) quantification and E) immunostaining images of CD3þ lymphocytes infiltration (red) at the site of coated islet implants with and without addition of TAC at day 28 and day 150 post-transplantation (green-insulin). Reproduced and adapted with permission [92]. Copyright 2022, Elsevier.…”

Recent Advances in Alginate-Based Hydrogels for Cell Transplantation Applications

“…Alginate/PD-TAMP/collagen Pancreatic islets Type 1 diabetes [282] Alginate/gelatin HFSCs and TGF-β2 Treating hair loss diseases [283] Alginate/gelatin hESC-RPE Treating retinal degenerative diseases [284] PDL: poly-d-lysine, PEI: polyethylenimine, PLL: poly(l-lysine), PEG: poly(ethylene glycol), PD-TAMP: polydopamine-coated TAC-loaded PLGA microparticles, HFSCs: hair follicle stem cells, NSCs: neural stem cells, MSCs: mesenchymal stem cells, VEGF: vascular endothelial growth factor, RBCs: red blood cells, hESC-RPE: human embryonic stem cell-derived retinal pigment epithelial, DPC: dermal papilla cell, FGF-2: fibroblast growth factor-2, TGF: transforming growth factor, hESC-RPE: human embryonic stem cell-derived retinal pigment epithelial, and PAMAM: poly(amino amide).…”