Wnt3a-Loaded Extracellular Vesicles Promote Alveolar Epithelial Regeneration after Lung Injury

Area of Science:

• Regenerative Medicine
• Pulmonary Medicine
• Cell Biology

Background:

• Wnt/β-catenin signaling is crucial for tissue regeneration but is compromised in chronic obstructive pulmonary disease (COPD).
• The hydrophobic nature of Wnt proteins hinders their therapeutic application for COPD.
• Extracellular vesicles (EVs) offer a potential delivery vehicle for therapeutic proteins.

Purpose of the Study:

• To develop an extracellular vesicle (EV)-based delivery system for Wnt3a to enhance lung regeneration.
• To investigate the therapeutic potential of engineered Wnt3a-loaded EVs in an emphysema model.

Main Methods:

• Engineered EVs (Wnt3aWG EVs) by co-expressing Wnt3a, WLS, and GPC6ΔGPI-C1C2.
• Validated Wnt3aWG EV bioactivity using TOPFlash assay and human pluripotent stem cell differentiation.
• Administered Wnt3aWG EVs intravenously in an elastase-induced emphysema mouse model.
• Analyzed therapeutic effects using pulmonary function tests, airspace measurements, and single-cell RNA sequencing.

Main Results:

• Wnt3aWG EVs successfully activated Wnt signaling and promoted cell growth in injured alveolar epithelial cells.
• Intravenous delivery of Wnt3aWG EVs significantly improved pulmonary function and reduced airspace enlargement in emphysema models.
• Single-cell RNA sequencing revealed that Wnt3aWG EVs activate regenerative programs in the lung.

Conclusions:

• Engineered EVs provide an effective method for delivering Wnt3a over long distances.
• EV-based Wnt3a delivery demonstrates significant therapeutic potential for lung repair and regeneration in COPD and emphysema.
• This approach represents a novel therapeutic strategy for treating lung injury and disease.