RESOURCES

Abstract
Repair of skin injuries is often hindered by the challenge of neovascularization, particularly in severely damaged wounds that struggle to self-heal, potentially leading to organ dysfunction or even death. Thus, promoting vascularization is crucial for effective skin repair. This study employed electrostatic spraying to fabricate methacrylated hyaluronic acid (HAMA) hydrogel microspheres for encapsulation of ectodermal mesenchymal stem cells (EMSCs), and optimization of the process parameters to assess their biocompatibility. Under in vitro conditions, EMSCs microspheres were successfully induced to differentiate into structures with vascular networks. Additionally, the optimal modification ratio of dopamine-modified hyaluronic acid (HADA) was determined to enhance the adhesive and mechanical properties of the dressing. Based on these findings, a dressing incorporating cell microspheres and adhesive hydrogels was developed. This dressing demonstrated formation of microvascular structures in vitro. Upon in vivo transplantation, it integrated tightly with surrounding tissues, modulated the inflammatory response, and accelerated wound healing in mouse model. This composite dressing, integrating cell-laden microspheres within a hydrogel’s framework, offers a simple and effective approach to promote skin microvascular.
Statement of significance
This study describes a hydrogel dressing that uses electrostatically sprayed methacrylated hyaluronic acid (HAMA) microspheres to encapsulate ectodermal mesenchymal stem cells (EMSCs). The hydrogel composition was optimized using dopamine-modified hyaluronic acid (HADA), which improved adhesion, while methacrylated polyvinyl alcohol (PVAMA) enhanced mechanical strength. This highly effective, low-risk hydrogel dressing promoted angiogenesis and accelerated wound healing. The results of this study highlight the potential of hydrogel dressing for clinical applications in tissue engineering and regenerative medicine, thus providing a promising strategy for the treatment of severe skin injuries.

Abstract
Abstract Plant-derived exosomes (PEs) possess an array of therapeutic properties, including antitumor, antiviral, and anti-inflammatory capabilities. They are also implicated in defensive responses to pathogenic attacks. Spinal cord injuries (SCIs) regeneration represents a global medical challenge, with appropriate research concentration on three pivotal domains: neural regeneration promotion, inflammation inhibition, and innovation and application of regenerative scaffolds. Unfortunately, the utilization of PE in SCI therapy remains unexplored. Herein, we isolated PE from the traditional Chinese medicinal herb, Lycium barbarum L. and discovered their inflammatory inhibition and neuronal differentiation promotion capabilities. Compared with exosomes derived from ectomesenchymal stem cells (EMSCs), PE demonstrated a substantial enhancement in neural differentiation. We encapsulated isoliquiritigenin (ISL)-loaded plant-derived exosomes (ISL@PE) from L. barbarum L. within a 3D-printed bionic scaffold. The intricate construct modulated the inflammatory response following SCI, facilitating the restoration of damaged axons and culminating in ameliorated neurological function. This pioneering investigation proposes a novel potential route for insoluble drug delivery via plant exosomes, as well as SCI repair. The institutional animal care and use committee number is UJS-IACUC-2020121602.