García García, PatriciaÉvora, CarmenDelgado, AraceliDíaz Rodríguez, Patricia2025-10-132025-10-132025-05-15García-García P, Évora C, Delgado A, Diaz-Rodriguez P. Chitosan-aloe vera scaffolds with tuned extracellular vesicles and histatin-5 display osteogenic and anti-biofilm activities. Int J Pharm. 2025 May 15;676:125592. doi: 10.1016/j.ijpharm.2025.125592. Epub 2025 Apr 12. PMID: 40228611.0378-5173https://hdl.handle.net/10347/43066The use of extracellular vesicles (EVs) has garnered significant attention as an alternative to cell-based therapies due to their stability and biocompatibility. In this study, we stimulated mesenchymal stem cells (MSCs) with therapeutic agents affecting the bone regenerative cascade, including bone morphogenetic protein 2 (BMP-2), stromal-derived factor (SDF-1), interleukin 4 (IL-4), alendronate (ALD) and osteogenic differentiation media to obtain osteogenic EVs. The tuned EVs were tested on MSCs and fibroblasts, selecting EVs-BMP-2 as suitable systems. Chitosan-aloe vera (AV) scaffolds were designed to allow for the loading and release of these EVs while leveraging the antibacterial and anti-inflammatory properties of AV. To enhance the dual effect on regeneration and antibacterial activity, poly(lactic-co-glycolic acid) (PLGA) microspheres encapsulating Histatin 5 (Hist-5) were incorporated to the scaffolds. Hist-5 encapsulation was successful, and effectively prevented Staphylococcus aureus biofilm formation on the scaffolds surface. The optimized chitosan-AV scaffolds loaded with EVs-BMP-2 promoted MSCs adhesion and proliferation and exhibited a 2-fold increase in osteogenic differentiation compared to chitosan scaffolds. This study demonstrates the successful combination of bioengineered EVs and Hist-5-loaded microspheres within a chitosan-AV scaffold, providing a promising dual approach for enhancing bone regeneration while reducing the risk of infection. These systems show potential as effective implants for bone fractures, offering both antibacterial and regenerative capabilities.eng© 2025 The Authors. Published by Elsevier B.V. This is an open access article under the CC BY-NC license (http://creativecommons.org/licenses/bync/4.0/).http://creativecommons.org/licenses/by/4.0/Aloe veraBacteria biofilmChitosan scaffoldsExtracellular vesiclesHistatin 5journal article10.1016/j.ijpharm.2025.125592open access