A Dense Fibrillar Collagen Scaffold Differentially Modulates Secretory Function of iPSC-Derived Vascular Smooth Muscle Cells to Promote Wound Healing

Abstract

The application of human-induced pluripotent stem cells (hiPSCs) to generate vascular smooth muscle cells (hiPSC-VSMCs) in abundance is a promising strategy for vascular regeneration. While hiPSC-VSMCs have already been utilized for tissue-engineered vascular grafts and disease modeling, there is a lack of investigations exploring their therapeutic secretory factors. The objective of this manuscript was to understand how the biophysical property of a collagen-based scaffold dictates changes in the secretory function of hiPSC-VSMCs while developing hiPSC-VSMC-based therapy for durable regenerative wound healing. We investigated the effect of collagen fibrillar density (CFD) on hiPSC-VSMC’s paracrine secretion and cytokines via the construction of varying density of collagen scaffolds. Our study demonstrated that CFD is a key scaffold property that modulates the secretory function of hiPSC-VSMCs. This study lays the foundation for developing collagen-based scaffold materials for the delivery of hiPSC-VSMCs to promote regenerative healing through guiding paracrine signaling pathways.

An In situ Collagen-HA Hydrogel System Promotes Survival and Preserves the Proangiogenic Secretion of hiPSC-derived Vascular Smooth Muscle Cells

“…However, collagen concentration had a greater impact on cell viability. This is consistent with our earlier report and can be attributed to the collagen fibrillar density (CFD) (Dash et al, 2020). The CFD increases with increasing concentration of collagen and impacts cell viability and proliferation.…”

“…C. Dash, Z. Jiang, C. Suh, & Y. Qyang, 2015a; Gorecka et al, 2019). Most recently, our studies revealed the proangiogenic and anti-inflammatory potential of these cells and their use in the treatment of acute and chronic wounds (Dash et al, 2020; Gorecka et al, 2020). While these reports further confirm the future translational implications of hiPSC-VSMCs, we see an unmet need for a suitable delivery system for hiPSC-VSMCs.…”

“…The hiPSC-VSMCs in pure population have been generated in abundance (Cheung, Bernardo, Trotter, Pedersen, & Sinha, 2012; Dash et al, 2015b; Dash et al, 2016; Patsch et al, 2015) and their ability to carry the disease mutations and to secrete collagen has been used to develop robust disease models (Atchison et al, 2020; Atchison, Zhang, Cao, & Truskey, 2017; Dash et al, 2016; Ge et al, 2012; Liu et al, 2011; Zhang et al, 2011) and vascular grafts (Gui et al, 2016; Karamariti et al, 2013; Luo et al, 2020), respectively. In addition, we recently reported the secretion of various growth factors and cytokines from these cells (Dash et al, 2020; Gorecka et al, 2020). Specifically, hiPSC-VSMCs, when embedded in a dense collagen scaffold, experienced a microenvironment attributable to a combination of mechanical forces and hypoxia that induced secretion of growth factors and cytokines including vascular endothelial growth factor (VEGF), basic fibroblast growth factor (bFGF), angiopoietin-1 (ANG-1), transforming growth factor (TGF)-β, platelet-derived growth factor (PDGF), matrix metalloproteinase (MMP)-2, stromal cell-derived factor (SDF)-1α, interleukin (IL)-10 and IL-8 (Dash et al, 2020).…”

“…In addition, we recently reported the secretion of various growth factors and cytokines from these cells (Dash et al, 2020; Gorecka et al, 2020). Specifically, hiPSC-VSMCs, when embedded in a dense collagen scaffold, experienced a microenvironment attributable to a combination of mechanical forces and hypoxia that induced secretion of growth factors and cytokines including vascular endothelial growth factor (VEGF), basic fibroblast growth factor (bFGF), angiopoietin-1 (ANG-1), transforming growth factor (TGF)-β, platelet-derived growth factor (PDGF), matrix metalloproteinase (MMP)-2, stromal cell-derived factor (SDF)-1α, interleukin (IL)-10 and IL-8 (Dash et al, 2020). Moreover, hiPSC-VSMCs in vivo exhibited proangiogenic and anti-inflammatory activities and were shown to promote regenerative healing in both acute and diabetic wound models in nude mice (Dash et al, 2020; Gorecka et al, 2020).…”

“…Extracellular matrix (ECM)-based biomaterials such as collagen have been designed for the delivery of stem cells’ beneficial properties (Dash et al, 2018; Hinderer, Layland, & Schenke-Layland, 2016). While collagen and its biophysical properties have been shown to have significant impact on stem cells’ therapeutic function, cross-linked in situ collagen-based hydrogels have been developed to enhance their stability and ease of application (Ahmed & Ffrench-Constant, 2016; Dash et al, 2020; Hou, Coller, Natu, Hastie, & Huang, 2016; Watt & Huck, 2013). Widely used chemical cross-linking methods have impact on collagen matrix architecture, stability, porosity, morphology, and function of stem cells (Depalle, Qin, Shefelbine, & Buehler, 2015; Gu, Shan, Ma, Tay, & Niu, 2019).…”