Mineral-Doped Poly(L-lactide) Acid Scaffolds Enriched with Exosomes Improve Osteogenic Commitment of Human Adipose-Derived Mesenchymal Stem Cells

Maria Giovanna Gandolfi; Chiara Gardin; Fausto Zamparini; Letizia Ferroni; Micaela Degli Esposti; Greta Parchi; Batur Ercan; Lucia Manzoli; Fabio Fava; Paola Fabbri; Carlo Prati; Barbara Zavan

doi:10.3390/nano10030432

Mineral-Doped Poly(L-lactide) Acid Scaffolds Enriched with Exosomes Improve Osteogenic Commitment of Human Adipose-Derived Mesenchymal Stem Cells

Nanomaterials (Basel). 2020 Feb 29;10(3):432. doi: 10.3390/nano10030432.

Authors

Affiliations

¹ Laboratory of Biomaterials and Oral Pathology, School of Dentistry, Department of Biomedical and Neuromotor Sciences, University of Bologna, 40125 Bologna, Italy.
² Medical Sciences Department, University of Ferrara, 44100 Ferrara, Italy.
³ Department of Civil, Chemical, Environmental and Materials Engineering, University of Bologna, 40136 Bologna, Italy.
⁴ Department of Metallurgical and Materials Engineering, 06800 Ankara, Turkey.
⁵ Cellular Signaling Laboratory, Institute of Human Anatomy, Department of Biomedical and Neuromotor Sciences, University of Bologna, 40126 Bologna, Italy.
⁶ Endodontic Clinical Section, School of Dentistry, Department of Biomedical and Neuromotor Sciences, University of Bologna, 40125 Bologna, Italy.

Abstract

Exosomes derived from mesenchymal stem cells are extracellular vesicles released to facilitate cell communication and function. Recently, polylactic acid (PLA), calcium silicates (CaSi), and dicalcium phosphate dihydrate (DCPD) have been used to produce bioresorbable functional mineral-doped porous scaffolds-through thermally induced phase separation technique, as materials for bone regeneration. The aim of this study was to investigate the effect of mineral-doped PLA-based porous scaffolds enriched with exosome vesicles (EVs) on osteogenic commitment of human adipose mesenchymal stem cells (hAD-MSCs). Two different mineral-doped scaffolds were produced: PLA-10CaSi-10DCPD and PLA-5CaSi-5DCPD. Scaffolds surface micromorphology was investigated by ESEM-EDX before and after 28 days immersion in simulated body fluid (HBSS). Exosomes were deposited on the surface of the scaffolds and the effect of exosome-enriched scaffolds on osteogenic commitment of hAD-MSCs cultured in proximity of the scaffolds has been evaluated by real time PCR. In addition, the biocompatibility was evaluated by direct-contact seeding hAD-MSCs on scaffolds surface-using MTT viability test. In both formulations, ESEM showed pores similar in shape (circular and elliptic) and size (from 10-30 µm diameter). The porosity of the scaffolds decreased after 28 days immersion in simulated body fluid. Mineral-doped scaffolds showed a dynamic surface and created a suitable bone-forming microenvironment. The presence of the mineral fillers increased the osteogenic commitment of hAD-MSCs. Exosomes were easily entrapped on the surface of the scaffolds and their presence improved gene expression of major markers of osteogenesis such as collagen type I, osteopontin, osteonectin, osteocalcin. The experimental scaffolds enriched with exosomes, in particular PLA-10CaSi-10DCPD, increased the osteogenic commitment of MSCs. In conclusion, the enrichment of bioresorbable functional scaffolds with exosomes is confirmed as a potential strategy to improve bone regeneration procedures.

Keywords: bioresorbable scaffold; calcium silicates; exosome enriched scaffolds; exosomes; green bioplastics; human adipose mesenchymal stem cells (hAD-MSCs), polylactic acid scaffold; nanodelivery; natural nanovesicles; personalized regenerative medicine.; regenerative bone healing.