Inhibiting scar formation via wearable multilayer stacked electret patch:Self-creation of persistent and customizable DC electric field for fibrogenic activity restriction

Electrical stimulation has recently received attention as noninvasive treatment in skin wound healing with its outstanding biological property for clinical setting.However,the complexity of equipment for applying appropriate electrical stimulation remains an ongoing challenge.Here,we proposed a strategy for skin scar inhibition by providing electrical stimulation via a multilayer stacked electret(MS-electret),which can generate direct current(DC)electric field(EF)without any power supply equipment.In addition,the MS-electret can easily control the intensity of EFs by simply stacking electret layers and maintain stable EF with the surface potential of 3400 V over 5 days owing to the injected charges on the electret surface.We confirmed inhibition of type 1 collagen andα-SMA expression of human dermal fibroblasts(hDFs)by 90%and 44%in vitro,indicating that the transition of hDFs to myofibroblasts was restricted by applying stable electrical stimulation.We further revealed a 20%significant decrease in the ratio of myofibroblasts caused by the MS-electret in vivo.These findings present that the MS-electret is an outstanding candidate for effective skin scar inhibition with a battery-free,physiological electrical microenvironment,and noninvasive treatment that allows it to prevent external infection.

Versatile effects of galectin-1 protein-containing lipid bilayer coating for cardiovascular applications

Modulating inflammatory cells in an implantation site leads to severe complications and still unsolved challenges for blood-contacting medical devices.Inspired by the role of galectin-1(Gal-1)in selective functions on multiple cells and immunomodulatory processes,we prepared a biologically target-specific surface coated with the lipid bilayer containing Gal-1(Gal-1-SLB)and investigate the proof of the biological effects.First,lipoamido-dPEG-acid was deposited on a gold-coated substrate to form a self-assembled monolayer and then conjugated dioleoylphosphatidylethanolamine(DOPE)onto that to produce a lower leaflet of the supported lipid bilayer(SLB)before fusing membrane-derived vesicles extracted from B16-F10 cells.The Gal-1-SLB showed the expected anti-fouling activity by revealing the resistance to protein adsorption and bacterial adhesion.In vitro studies showed that the Gal-1-SLB can promote endothelial function and inhibit smooth muscle cell proliferation.Moreover,Gal-1-SLB presents potential function for endothelial cell migration and angiogenic activities.In vitro macrophage culture studies showed that the Gal-1-SLB attenuated the LPS-induced inflammation and the production of macrophage-secreted inflammatory cytokines.Finally,the implanted Gal-1-SLB reduced the infiltration of immune cells at the tissue-implant interface and increased markers for M2 polarization and blood vessel formation in vivo.This straightforward surface coating with Gal-1 can be a useful strategy for modulating the vascular and immune cells around a blood-contacting device.