Using Electrospun Scaffolds to Promote Macrophage Phenotypic Modulation and Support Wound Healing

Abstract

Abstract:The development of pressure ulcers in spinal cord injury patients is extremely common, often requiring extensive surgical procedures. Macrophages (MACs) play a crucial role in the innate immune system, contributing to wound healing and overall regeneration. MACs have been found to possess the potential to be activated by external factors from their M0 inactive state to an M1 proinflammatory or M2 regenerative state. This study conducted a comprehensive evaluation of MAC phenotype in response to electrospun scaffolds of varying material fiber/pore diameter, fiber stiffness, and +/− inclusion of platelet-rich plasma (PRP). Generally, it was found that the addition of PRP resulted in decreased pore size, where 5 silk fibroin (SF) had the stiffest fibers. Furthermore, PRP scaffolds demonstrated an increased production of VEGF and chemotaxis. The polycaprolactone (PCL) and SF scaffolds had the largest cell infiltration and proliferation. Overall, it was found that 5% SF had both ideal fiber and pore structure, allowing for cell infiltration further enhanced by the presence of PRP. Additionally, this scaffold led to a reasonable production of VEGF while still allowing fibroblast proliferation to occur. These results suggest that such a scaffold could provide an off-the-shelf product capable of modifying the local MAC response.

Precisely defined fiber scaffolds with 40 μm porosity induce elongation driven M2-like polarization of human macrophages

“…only with the surface of a single fiber. To allow for better comparison of our newly established, highly ordered scaffolds with previous studies using random scaffold geometries [52,53], the MEW procedure was additionally adjusted to produce randomly disordered scaffolds that mimic electrospun fiber constructs.…”

Advance in topical biomaterials and mechanisms for the intervention of pressure injury

“… 143 There was another interesting finding that increased biomaterial (electrospun scaffolds) fiber and pore size could induce M2 macrophage conversion which contributes to fibroblast proliferation. 144 However, the authors detected cellular infiltration and VEGF release, which is one of factors that M2 macrophages produce, rather than the specific markers of M2 phenotype to confirm their hypothesis. In addition, the additive of chondroitin sulfate at a concentration ranging from 100 to 1000 μg/mL induced the production of ROS and proinflammatory cytokines.…”

Anin vitroanalysis of injectable methacrylated alginate cryogels incorporated with PRP targeting minimally invasive treatment of bone nonunion

“…The resulting PRP solution was stored at −80 °C until use. To prepare powdered PRP for incorporation into the scaffolds, the PRP solution was thawed at 4 °C, mixed, frozen for 1 h at −80 °C, and then lyophilized to create powdered PRP [27,[34][35][36].…”

“…Platelet-rich plasma (PRP) has become increasingly popular as a clinical treatment for illnesses ranging from osteoarthritis and Achilles tendonitis to bone regeneration; with the 300+bioactive molecules aiding in the regeneration process of many tissues [21][22][23]. Other tissues, such as skin, have also been studied for the potential applications in healing dermal wounds [24][25][26][27]. In delayed fracture healing, the fracture lacks an appropriate blood supply that provides the injury with signaling molecules that dictate the body's inflammatory response.…”