AAV-mediated MUC5AC siRNA delivery to prevent mucociliary dysfunction in asthma

Area of Science:

• Pulmonary Medicine
• Gene Therapy
• Respiratory Cell Biology

Background:

• Mucus in the lungs is primarily composed of mucin 5B (MUC5B) and mucin 5AC (MUC5AC).
• Asthma is characterized by increased MUC5AC production, impairing mucociliary clearance (MCC) and causing mucus plugs.
• MUC5AC is a potential therapeutic target for managing asthma-related airway obstruction.

Purpose of the Study:

• To investigate adeno-associated virus serotype 6 (AAV6) as a gene delivery vector for reducing MUC5AC expression in airway epithelial cells.
• To evaluate the efficacy of AAV6-mediated siRNA delivery in suppressing MUC5AC and restoring MCC in asthma models.

Main Methods:

• Adeno-associated virus serotype 6 (AAV6) was used to deliver siRNA targeting MUC5AC to airway epithelial cells in vitro and in vivo.
• Transduction efficiency and transgene expression in mucus-secreting goblet cells were assessed.
• Multiple particle tracking analysis was employed to evaluate AAV6's ability to penetrate mucus barriers.
• Human airway epithelial (HAE) cell cultures were treated with AAV6-MUC5AC siRNA before IL-13 challenge to assess MUC5AC expression and MCC.

Main Results:

• AAV6 effectively transduced airway epithelial cells in vitro and in vivo, with high expression in goblet cells.
• AAV6 demonstrated the ability to penetrate both normal and MUC5AC-enriched mucus.
• Treatment with AAV6-MUC5AC siRNA significantly reduced MUC5AC mRNA and protein levels in IL-13-stimulated HAE cultures.
• AAV6-MUC5AC siRNA treatment maintained normal mucociliary transport in IL-13-stimulated HAE cultures.

Conclusions:

• AAV6 serves as an effective viral vector for gene delivery to airway epithelial cells, including mucus-producing goblet cells.
• Inhaled AAV6-based gene therapy can suppress MUC5AC overexpression in asthma models.
• This approach holds promise for restoring normal airway clearance function in asthma by targeting MUC5AC.