Journal Article

Osteogenic human MSC-derived extracellular vesicles regulate MSC activity and osteogenic differentiation and promote bone regeneration in a rat calvarial defect model

Gruber, Reinhard, Mustafa, Kamal, Al-Sharabi, Niyaz, Mohamed-Ahmed, Samih, Shanbhag, Siddharth, Tangl, Stefan, Elnour, Rammah, Yamada, Shuntaro, Rana, Neha, Kampleitner, Carina, Birkeland, Even

2024

Overview

Background There is growing evidence that extracellular vesicles (EVs) play a crucial role in the paracrine mechanisms of transplanted human mesenchymal stem cells (hMSCs). Little is known, however, about the influence of microenvironmental stimuli on the osteogenic effects of EVs. This study aimed to investigate the properties and functions of EVs derived from undifferentiated hMSC (Naïve-EVs) and hMSC during the early stage of osteogenesis (Osteo-EVs). A further aim was to assess the osteoinductive potential of Osteo-EVs for bone regeneration in rat calvarial defects. Methods EVs from both groups were isolated using size-exclusion chromatography and characterized by size distribution, morphology, flow cytometry analysis and proteome profiling. The effects of EVs (10 µg/ml) on the proliferation, migration, and osteogenic differentiation of cultured hMSC were evaluated. Osteo-EVs (50 µg) or serum-free medium (SFM, control) were combined with collagen membrane scaffold (MEM) to repair critical-sized calvarial bone defects in male Lewis rats and the efficacy was assessed using µCT, histology and histomorphometry. Results Although Osteo- and Naïve-EVs have similar characteristics, proteomic analysis revealed an enrichment of bone-related proteins in Osteo-EVs. Both groups enhance cultured hMSC proliferation and migration, but Osteo-EVs demonstrate greater efficacy in promoting in vitro osteogenic differentiation, as evidenced by increased expression of osteogenesis-related genes, and higher calcium deposition. In rat calvarial defects, MEM with Osteo-EVs led to greater and more consistent bone regeneration than MEM loaded with SFM. Conclusions This study discloses differences in the protein profile and functional effects of EVs obtained from naïve hMSC and hMSC during the early stage of osteogenesis, using different methods. The significant protein profile and cellular function of EVs derived from hMSC during the early stage of osteogenesis were further verified by a calvarial bone defect model, emphasizing the importance of using differentiated MSC to produce EVs for bone therapeutics.

• Publisher: BioMed Central,BioMed Central Ltd,Springer Nature B.V,BMC
• Subject: Animals / Antigens / Biomedical and Life Sciences / Biomedical Engineering and Bioengineering / Biomedical materials / Bone growth / Bone regeneration / Bone Regeneration - physiology / Cell Biology / Cell Differentiation / Chromatography / Collagen / Cytokines / Extracellular vesicles / Extracellular Vesicles - metabolism / Flow cytometry / Genes / Growth factors / Humans / Life Sciences / Male / Membranes / Mesenchymal stem cells / Mesenchymal Stem Cells - metabolism / MicroRNAs / Naïve-EVs / Osteo-EVs / Osteogenesis / Osteogenesis - genetics / Paracrine signalling / Proteomes / Proteomics / Rat calvarial defects / Rats / Rats, Inbred Lew / Regeneration / Regenerative Medicine/Tissue Engineering / Scientific equipment and supplies industry / Serum-free medium / Size distribution / Stem cell transplantation / Stem Cells / Transplantation