The immune function of dermal fibroblasts in skin defence against pathogens

Increased splicing of CXCR3 isoform B (CXCR3B) by impaired NRF2 signaling leads to melanocyte apoptosis in active vitiligo

Apoptotic melanocytes (MCs) may release neoantigenic epitopes preceding epidermal infiltration by autoreactive CD8+ T cells in early vitiligo. However, the mechanism by which vitiligo MCs are prone to apoptosis under oxidative stress remains elusive. Pro-apoptotic receptor C-X-C motif chemokine receptor 3 isoform B (CXCR3B) is critical for inducing MC apoptosis in the inflammatory microenvironment of lesional vitiligo skin. Here, we show that C-X-C motif chemokine ligand 10 (CXCL10), a functional ligand for CXCR3B, is upregulated in primary dermal fibroblasts and in CD90+ reticular fibroblasts of vitiligo skin. The number of CXCR3B+ MCs was increased in active vitiligo skin compared with healthy skin and stable vitiligo skin. Mechanistically, impaired nuclear factor erythroid 2-related factor 2 (NRF2) signaling in oxidatively stressed MCs leads to the elevated expression of CXCR3B and increased apoptosis. The overexpression of NRF2 prevents MCs from CXCL10-induced apoptosis through upregulation of pro-survival receptor CXCR3 isoform A (CXCR3A). Overall, MCs expressing CXCR3B are more susceptible to apoptosis. Suppressing CXCR3B could be a promising therapeutic approach to extinguish inflammation in vitiligo skin.

A versatile LTF-GO/gel hydrogel with antibacterial and antioxidative attributes for skin wound healing

Skin wound healing will become a pressing and difficult problem following injury to the skin structure. Persistent wounds, in particular, become more vulnerable to bacterial infections, which can contribute to persistent skin inflammation. Therefore, it is critical to create a wound dressing that promotes wound healing while also being antimicrobial. In the present work, a multifunctional biological activity hydrogel formed by enzymatic cross-linking was developed by introducing graphene oxide (GO) and lactoferrin to gelatin hydrogel. Furthermore, by incorporating lactoferrin, the composite hydrogels exhibit excellent in vitro antibacterial and biocompatibility. According to cell experiments, the LTF-GO/Gel hydrogel can improve wound healing by enhancing L929 cell migration. Interestingly, under near-infrared light, LTF-GO/Gel hydrogel increases the generation of singlet oxygen (1O2) and hydroxyl radical (-OH), making the hydrogel system excellent antioxidant and antibacterial capabilities, these results demonstrate that the LTF-GO/Gel hydrogel has clinical promise as a wound dressing for wound healing. In vivo experiments unequivocally establish the capacity of the LTF-GO/Gel hydrogel to expedite wound healing and mitigate inflammation. This hydrogel, therefore, harbors immense potential for applications in wound healing.

Modeling of solar UV-induced photodamage on the hair follicles in human skin organoids

Solar ultraviolet (sUV) exposure is known to cause skin damage. However, the pathological mechanisms of sUV on hair follicles have not been extensively explored. Here, we established a model of sUV-exposed skin and its appendages using human induced pluripotent stem cell-derived skin organoids with planar morphology containing hair follicles. Our model closely recapitulated several symptoms of photodamage, including skin barrier disruption, extracellular matrix degradation, and inflammatory response. Specifically, sUV induced structural damage and catagenic transition in hair follicles. As a potential therapeutic agent for hair follicles, we applied exosomes isolated from human umbilical cord blood-derived mesenchymal stem cells to sUV-exposed organoids. As a result, exosomes effectively alleviated inflammatory responses by inhibiting NF-κB activation, thereby suppressing structural damage and promoting hair follicle regeneration. Ultimately, our model provided a valuable platform to mimic skin diseases, particularly those involving hair follicles, and to evaluate the efficacy and underlying mechanisms of potential therapeutics.

Piezoelectric and Triboelectric Nanogenerators for Enhanced Wound Healing

Wound healing is a highly orchestrated biological process characterized by sequential phases involving inflammation, proliferation, and tissue remodeling, and the role of endogenous electrical signals in regulating these phases has been highlighted. Recently, external electrostimulation has been shown to enhance these processes by promoting cell migration, extracellular matrix formation, and growth factor release while suppressing pro-inflammatory signals and reducing the risk of infection. Among the innovative approaches, piezoelectric and triboelectric nanogenerators have emerged as the next generation of flexible and wireless electronics designed for energy harvesting and efficiently converting mechanical energy into electrical power. In this review, we discuss recent advances in the emerging field of nanogenerators for harnessing electrical stimulation to accelerate wound healing. We elucidate the fundamental mechanisms of wound healing and relevant bioelectric physiology, as well as the principles underlying each nanogenerator technology, and review their preclinical applications. In addition, we address the prominent challenges and outline the future prospects for this emerging era of electrical wound-healing devices.