Precision‐porous templated scaffolds of varying pore size drive dendritic cell activation

Abstract

Scaffold based systems have shown significant potential in modulating immune responses in vivo. While there has been much attention on macrophage interactions with tissue engineered scaffolds for tissue regeneration, fewer studies have looked at the effects of scaffold design on the response of immune cells−that is, dendritic cells (DCs). Here, we present the effects of varying pore size of poly (2-hydroxyethyl methacrylate) (pHEMA) and poly(dimethylsiloxane) (PDMS, silicone) scaffolds on the maturation and in vivo enrichment of DCs. We employ a precision templating method to make 3-D porous polymer scaffolds with uniformly defined and adjustable architecture. Hydrophilic pHEMA and hydrophobic PDMS scaffolds were fabricated in three pore sizes (20, 40, 90 μm) to quantify scaffold pore size effects on DCs activation/maturation in vitro and in vivo. In vitro results showed that both pHEMA and PDMS scaffolds could promote maturation in the DC cell line, JAWSII, that resembled lipopolysaccharide (LPS)-activated/matured DCs (mDCs). Scaffolds with smaller pore sizes correlate with higher DC maturation, regardless of the polymer used. In vivo, when implanted subcutaneously in C57BL/6J mice, scaffolds with smaller pore sizes also demonstrated more DCs recruitment and more sustained activation. Without the use of DC chemo-attractants or chemical adjuvants, our results suggested that DC maturation and scaffold infiltration profile can be modulated by simply altering the pore size of the scaffolds.

Injectable Biodegradable Chitosan‐Alginate 3D Porous Gel Scaffold for mRNA Vaccine Delivery

“…Based on our positive results, the chitosan‐alginate gel scaffold could be a suitable candidate for a subcutaneous delivery system of mRNA vaccines. Various scaffolds have been developed and widely used on for cell modification, tissue regeneration, and drug or gene delivery, but none of them considered nucleic acid vaccine loading and delivery.…”

The Overview of Porous, Bioactive Scaffolds as Instructive Biomaterials for Tissue Regeneration and Their Clinical Translation

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Biomaterials for vaccine-based cancer immunotherapy

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