Enhanced Auricular Cartilage Regeneration via 3D-Printed Hydrogel With miR-92a-3p-Enriched Platelet-Rich...

Area of Science:

• Regenerative Medicine
• Biomaterials Science
• Tissue Engineering

Background:

• Auricular cartilage reconstruction for microtia is challenging due to chondrocyte quiescence.
• Current cartilage tissue engineering methods struggle with efficient chondrogenesis.

Purpose of the Study:

• To develop an effective strategy for auricular cartilage regeneration using engineered extracellular vesicles and 3D bioprinting.
• To investigate the role of platelet-derived extracellular vesicles (PEVs) and miRNA-92a-3p in enhancing chondrogenesis.

Main Methods:

• Engineered PEVs carrying miRNA-92a-3p (miR@PEVs) were developed.
• A double-network hydrogel scaffold (ElaMA/GelMA) was fabricated using 3D bioprinting.
• In vitro and in vivo studies assessed chondrogenesis, biocompatibility, and mechanical properties.

Main Results:

• miR@PEV-laden scaffolds demonstrated superior chondrogenesis compared to controls in vivo.
• Scaffold's Young's modulus approached native cartilage after one month.
• In vitro, miR@PEVs promoted chondrocyte proliferation, migration, and M2 macrophage polarization via miR-92a-3p.
• miR-92a-3p suppressed SMAD7, activating TGFβ/Smad signaling.

Conclusions:

• Engineered miR@PEVs integrated into 3D-printed scaffolds offer a promising solution for auricular reconstruction.
• This approach overcomes limitations in chondrogenesis and ear regeneration.
• The strategy holds potential for total ear reconstruction in microtia patients.