The Effect of a TLR3 Agonist on Airway Allergic Inflammation and Viral Infection in Immunoproteasome-Deficient Mice

Area of Science:

• Immunology
• Respiratory Medicine
• Molecular Biology

Background:

• Allergic asthma involves type 2 inflammation and is worsened by allergens like house dust mite (HDM) and rhinovirus infections.
• The immunoproteasome (IP) is induced by inflammation during viral infections, but its role in allergic airway inflammation is unclear.

Purpose of the Study:

• To investigate the role of the immunoproteasome (IP) in airway allergic inflammation and rhinovirus infection.
• To evaluate the therapeutic potential of TLR3 agonist (Poly I:C) in a mouse model of allergic asthma and rhinovirus infection.

Main Methods:

• Wild-type (WT) and IP knockout (KO) mice were challenged with HDM and subsequently infected with rhinovirus 1B (RV-A1B).
• Lung inflammatory cells, viral load, and IFN-beta expression were assessed.
• IP KO mice received Poly I:C treatment after RV-A1B infection.

Main Results:

• IP KO mice exhibited increased lung eosinophils and neutrophils, higher viral load, and reduced IFN-beta expression compared to WT mice.
• Poly I:C treatment in HDM-challenged IP KO mice significantly increased IFN-beta expression and reduced viral load.
• Poly I:C treatment had minimal impact on inflammatory cell counts in IP KO mice.

Conclusions:

• The immunoproteasome plays a crucial role in controlling excessive inflammation and viral infection in allergen-exposed mice.
• Poly I:C demonstrates therapeutic potential for enhancing antiviral responses and reducing viral burden in lungs with IP deficiency.