Tunable Microfibers Suppress Fibrotic Encapsulation via Inhibition of TGFβ Signaling

Autor: Julia R. Greer, Alessandro Maggi, Jubin Ryu, Jessica L. Allen, Bianca Flores, Tejal A. Desai
Rok vydání: 2016
Předmět:
Zdroj: Tissue Engineering Part A. 22:142-150
ISSN: 1937-335X
1937-3341
DOI: 10.1089/ten.tea.2015.0087
Popis: Fibrotic encapsulation limits the efficacy and lifetime of implantable biomedical devices. Microtopography has shown promise in the regulation of myofibroblast differentiation, a key driver of fibrotic encapsulation. However, existing studies have not systematically isolated the requisite geometric parameters for suppression of myofibroblast differentiation via microtopography, and there has not been in vivo validation of this technology to date. To address these issues, a novel lamination method was developed to afford more control over topography dimensions. Specifically, in this study we focus on fiber length and its effect on myofibroblast differentiation. Fibroblasts cultured on films with microfibers exceeding 16 μm in length lost the characteristic morphology associated with myofibroblast differentiation, while shorter microfibers of 6 μm length failed to produce this phenotype. This increase in length corresponded to a 50% decrease in fiber stiffness, which acts as a mechanical cue to influence myofibroblast differentiation. Longer microfiber films suppressed expression of myofibroblast specific genes (αSMA, Col1α2, and Col3α1) and TGFβ signaling components (TGFβ1 ligand, TGFβ receptor II, and Smad3). 16 μm long microfiber films implanted subcutaneously in a mouse wound-healing model generated a substantially thinner fibrotic capsule and less deposition of collagen in the wound bed. Together, these results identify a critical feature length threshold for microscale topography-mediated repression of fibrotic encapsulation. This study also demonstrates a simple and powerful strategy to improve surface biocompatibility and reduce fibrotic encapsulation around implanted materials.
Databáze: OpenAIRE