Bioengineered\ua0braided micro-nano (multiscale) fibrous scaffolds for tendon reconstruction

A braided multiscale fibrous scaffold consisting of aligned PCL micro/collagen-bFGFnano fibers was fabricated (mPCL-nCol-bFGF) to mimic native tendon tissue architecture which was further coated with alginate to aid in prevention of peritendinous adhesion. The bFGF release kinetics showed a sustained release of growth factors for a period of 20 days. Further, in vitro cell viability, attachment, and proliferation were performed using rabbit tenocytes under static and dynamic conditions. mPCL-nCol-bFGF showed a higher cell proliferation and enhanced expression of tenogenic markers compared to mPCL-nCol (braided scaffold without bFGF). When subjected to dynamic stimulation in a bioreactor, mPCL-nCol-bFGF-DS (braided scaffold with bFGF after dynamic stimulation) showed enhanced cellular proliferation and tenogenic marker expression, compared to mPCL-nCol-bFGF. The in vivo studies of the cell seeded scaffold after dynamic stimulation in Achilles tendon defect model showed tendon tissue regeneration with aligned collagen morphology within 12 weeks of implantation

Paintable Decellularized‐ECM Hydrogel for Preventing Cardiac Tissue Damage

Abstract The tissue‐specific heart decellularized extracellular matrix (hdECM) demonstrates a variety of therapeutic advantages, including fibrosis reduction and angiogenesis. Consequently, recent research for myocardial infarction (MI) therapy has utilized hdECM with various delivery techniques, such as injection or patch implantation. In this study, a novel approach for hdECM delivery using a wet adhesive paintable hydrogel is proposed. The hdECM‐containing paintable hydrogel (pdHA_t) is simply applied, with no theoretical limit to the size or shape, making it highly beneficial for scale‐up. Additionally, pdHA_t exhibits robust adhesion to the epicardium, with a minimal swelling ratio and sufficient adhesion strength for MI treatment when applied to the rat MI model. Moreover, the adhesiveness of pdHA_t can be easily washed off to prevent undesired adhesion with nearby organs, such as the rib cages and lungs, which can result in stenosis. During the 28 days of in vivo analysis, the pdHA_t not only facilitates functional regeneration by reducing ventricular wall thinning but also promotes neo‐vascularization in the MI region. In conclusion, the pdHA_t presents a promising strategy for MI treatment and cardiac tissue regeneration, offering the potential for improved patient outcomes and enhanced cardiac function post‐MI