A hydrogel platform delivering mesenchymal stem cell lysate for potential myocardial tissue repair

Study on the physicochemical properties of MSCs exosome-loaded viscous hydrogels and their mechanism of regulating angiogenesis

Gelatin Methacrylate as a Mesenchymal Stem Cell Delivery Vehicle: Experimental and Semi-Quantitative Evaluation Under Metabolic Stress.

Stem cell-based therapies derived from various sources hold significant potential in regenerative medicine due to their unique properties, particularly their ability to differentiate, self-renew, and modulate the immune system. A polymer-encapsulated Mesenchymal stem cell (MSC) approach can create protective environments for stem cells, enhancing overall therapeutic efficacy. Gelatin Methacrylate (GelMA) is used as a model extracellular matrix to encapsulate MSCs for potential applications in cell-based therapy and bioprinting. This study aims to understand the limitations of GelMA-encapsulation-based cell therapy for an injured tissue. Due to the harsh microenvironment at the implantation site, directly injected stem cells for treatment are affected by factors such as nutrient and oxygen deprivation, immune rejection, reduced cell retention, and inflammatory cytokines. In the current study, we tried to mimic this system. We optimized the GelMA hydrogel cell-encapsulation composition from synthesis through physicochemical characterization, and then tested its cytocompatibility with MSCs. We have further performed numerical modeling to understand and control the behavior of MSCs within the 3D GelMA hydrogel construct under varying metabolic and immunological stress microenvironmental conditions, thereby optimizing the boundary conditions of GelMA-based cell delivery systems.

Bioactive adipose-derived ECM hydrogel loaded with cytokine-releasing microspheres promotes spinal cord repair by suppressing inflammation, apoptosis, oxidative stress, and ferroptosis

An Intracellular Lysate Sustained-Release Nanohydrogel Promotes Osteogenesis and Angiogenesis

Introduction and aims Nanomaterials hold great promise for applications in bone tissue engineering. Dental pulp stem cell (DPSC) lysate, as a kind of intracellular lysate, has attracted increasing attention as a bioactive, cell-free therapeutic component in bone tissue engineering. Zeolitic imidazolate framework-8 (ZIF-8), a zinc-based MOF with sodalite topology, features high surface area, porosity and stability under physiological conditions. Its excellent biocompatibility, pH-responsive degradability and drug-loading capacity make it widely applicable in drug delivery. Methods In this study, we developed a strategy for delivering DPSC lysate by encapsulating it within Poloxamer hydrogel and ZIF-8 nanoparticles, successfully synthesising IV@ZIF-8@Poloxamer Hydrogel (INZG). Results The resulting INZG exhibited excellent biocompatibility and supported cell viability. In vitro and vivo experiments demonstrated that INZG possessed outstanding osteogenic and angiogenic properties, promoting bone and blood vessel formation via activation of the P38/MAPK and PDGFRβ/PI3K/AKT signalling pathways, respectively. Conclusion In summary, this study is the first to propose that INZG possess excellent biocompatibility and bioactive functions that promote both osteogenic and angiogenic differentiation. Clinical relevance This study provides a safe and effective new strategy for the treatment of various bone defects and lays a theoretical foundation for the development of vascularised bone scaffolds.

Mesenchymal Stromal Cell-Derived Extracellular Vesicles in Tissue Repair: Applications and Mechanisms

Mesenchymal stromal/stem cell-derived extracellular vesicles (MSC-EVs), including preparations frequently described as exosomes, are being investigated as cell-free candidates for tissue repair. These lipid-bilayer-delimited particles carry proteins, lipids, and nucleic acids that may modulate immune responses, cell survival, angiogenesis, proliferation, migration, and extracellular-matrix remodeling in experimental systems. This review summarizes the biological characteristics of MSC-EVs, commonly used separation methods, proposed mechanisms of action, and preclinical applications in peripheral nerve repair, bone regeneration, and cutaneous wound healing. It also considers major barriers to translation, including inconsistent nomenclature and characterization, variable yield, purity, composition, and potency, limited tissue retention and targeting, and the absence of broadly standardized, scalable manufacturing processes. Future studies should use rigorous EV characterization, mechanism-linked potency assays, reproducible production protocols, and appropriately designed preclinical and clinical studies to establish the safety and efficacy of MSC-EV-based interventions.

Biomaterial-Assisted Stem Cell Therapy and Exosome Delivery in Myocardial Infarction: A Narrative Review

Current evidence demonstrates that injectable hydrogels, extracellular matrix-derived scaffolds, cardiac patches, conductive biomaterials, and multifunctional delivery platforms improve therapeutic retention, prolong paracrine signaling, and actively modulate inflammation, angiogenesis, fibrosis, and extracellular matrix remodeling, resulting in superior functional recovery compared with conventional delivery approaches in preclinical models.