A nature-derived, strong adhesive hydrogel microsphere for wet tissue repair: Multifunctional and clinical potential

In dynamic and fluid-rich environments, achieving stable bioscaffold adhesion to tissue surfaces while facilitating therapeutic delivery always presents significant challenges. Inspired by the nature adhesive mechanisms of skin section of Andrias davidianus (SSAD), we engineered SSAD@GelMA microspheres (SGM) as a novel multifunctional biomimetic platform, combining strong bioadhesion, cell/drug delivery capabilities, and extracellular matrix (ECM) remodeling. Preclinical evaluation in wound models demonstrated SGM exceptional adhesive strength, maintaining stable attachment even under continuous fluid shear stress. Unlike conventional hydrogel microspheres, the unique multifunctionality of SSAD enables SGM to serve dual roles as both an advanced biomimetic platform and an effective tissue-repairing agent for wet wound healing applications. Through efficient delivery of therapeutic agents or cells in wet environments and promotion of ECM remodeling, SGM significantly enhanced tissue repair across various in vivo wet tissue models, including bone tissue, cartilage tissue, soft tissue. These findings introduce a promising class of wet-adhesive microspheres with broad potential for adaptation to diverse fluid-rich tissue regeneration scenarios.