5 research outputs found
Encapsulation of Human Natural and Induced Regulatory T-Cells in IL-2 and CCL1 Supplemented Alginate-GelMA Hydrogel for 3D Bioprinting
2020 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim Regulatory T-cells (Tregs) are important modulators of the immune system through their intrinsic suppressive functions. Systemic adoptive transfer of ex vivo expanded Tregs has been extensively investigated for allogeneic transplantation. Due to the time-consuming and costly expansion protocols of Tregs, more targeted approaches could be beneficial. The encapsulation of human natural and induced Tregs for localized immunosuppression is described for the first time. Tregs encapsulated in alginate-gelatin methacryloyl hydrogel remain viable, phenotypically stable, functional, and confined in the structure. Supplementation of the hydrogel with the Treg-specific bioactive factors interleukin-2 and chemokine ligand 1 improves Treg viability, suppressive phenotype, and function, and attracts to the structure CCR8+ T-cells enriched with anti-inflammatory subpopulations, including Tregs, from human peripheral blood. Furthermore, these findings are applicable to 3D bioprinting. Co-axial printing of murine pancreatic islets with human natural and induced Tregs protects the islets from xenoresponse upon co-culture with human peripheral blood mononuclear cells. This establishes the co-encapsulation of Tregs by co-axial 3D bioprinting as a valid option for providing local immune protection to allogeneic cellular transplants such as pancreatic islets
Encapsulation of Human Natural and Induced Regulatory T-Cells in IL-2 and CCL1 Supplemented Alginate-GelMA Hydrogel for 3D Bioprinting
2020 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim Regulatory T-cells (Tregs) are important modulators of the immune system through their intrinsic suppressive functions. Systemic adoptive transfer of ex vivo expanded Tregs has been extensively investigated for allogeneic transplantation. Due to the time-consuming and costly expansion protocols of Tregs, more targeted approaches could be beneficial. The encapsulation of human natural and induced Tregs for localized immunosuppression is described for the first time. Tregs encapsulated in alginate-gelatin methacryloyl hydrogel remain viable, phenotypically stable, functional, and confined in the structure. Supplementation of the hydrogel with the Treg-specific bioactive factors interleukin-2 and chemokine ligand 1 improves Treg viability, suppressive phenotype, and function, and attracts to the structure CCR8+ T-cells enriched with anti-inflammatory subpopulations, including Tregs, from human peripheral blood. Furthermore, these findings are applicable to 3D bioprinting. Co-axial printing of murine pancreatic islets with human natural and induced Tregs protects the islets from xenoresponse upon co-culture with human peripheral blood mononuclear cells. This establishes the co-encapsulation of Tregs by co-axial 3D bioprinting as a valid option for providing local immune protection to allogeneic cellular transplants such as pancreatic islets
Murine and Non-Human Primate Dendritic Cell Targeting Nanoparticles for <i>in Vivo</i> Generation of Regulatory T‑Cells
Porous
silicon nanoparticles (pSiNP), modified to target dendritic
cells (DC), provide an alternate strategy for the delivery of immunosuppressive
drugs. Here, we aimed to develop a DC-targeting pSiNP displaying c-type
lectin, dendritic cell-specific intercellular adhesion molecule-3-grabbing
non-integrin (DC-SIGN), and CD11c monoclonal antibodies. The <i>in vivo</i> tracking of these fluorescent DC-targeting nanoparticles
was assessed in both C57BL/6 mice and common marmosets (<i>Callithrix
jacchus</i>) by intravenous injection (20 mg/kg). Rapamycin and
ovalbumin (OVA)<sub>323–339</sub> peptide loaded pSiNP were
employed to evaluate their ability to generate murine CD4<sup>+</sup>CD25<sup>+</sup>FoxP3<sup>+</sup> regulatory T-cells <i>in vivo</i> within OVA sensitized mice. <i>In vivo,</i> pSiNP migrated
to the liver, kidneys, lungs, and spleen in both mice and marmosets.
Flow cytometry confirmed pSiNP uptake by splenic and peripheral blood
DC when functionalized with targeting antibodies. C57BL/6 OVA sensitized
mice injected with CD11c-pSiNP loaded with rapamycin + OVA<sub>323–339</sub> produced a 5-fold higher number of splenic regulatory T-cells compared
to control mice, at 40 days post-pSiNP injection. These results demonstrate
the importance of the immobilized targeting antibodies to enhance
cellular uptake and enable the <i>in vivo</i> generation
of splenic regulatory T-cells