To cite this article: Shin T-S, Kim JH, Kim Y-S, Jeon SG, Zhu Z, Gho YS, Kim Y-K. Extracellular vesicles are key intercellular mediators in the development of immune dysfunction to allergens in the airways. Allergy 2010; 65: 1256–1265.
Background: Previous evidence indicates that inhalation of lipopolysaccharide (LPS)-containing with allergens induced mixed Th1 and Th17 cell responses in the airways. Extracellular vesicles (EVs) are nanometer-sized spherical, lipid-bilayered structures and are recently in the public eye as an intercellular communicator in immune responses.
Objective: To evaluate the role of EVs secreted by LPS inhalation in the development of airway immune dysfunction in response to allergens.
Methods: Extracellular vesicles in bronchoalveolar lavage fluids of BALB/c mice were isolated and characterized 24 h after applications to the airway of 10 μg of LPS for 3 days. To evaluate the role of LPS-induced EVs on the development of airway immune dysfunction, in vivo and in vitro experiments were performed using the isolated LPS-induced EVs.
Results: The inhalation of LPS enhanced EVs release into the BAL fluid, when compared to the application of PBS. Airway sensitization with allergens and LPS-induced EVs resulted in a mixed Th1 and Th17 cell responses, although that with allergens and PBS-induced EVs induced immune tolerance. In addition, LPS-induced EVs enhanced the production of Th1- and Th17-polarizing cytokines (IL-12p70 and IL-6, respectively) by lung dendritic cells. Moreover, the immune responses induced by the LPS-induced EVs were blocked by denaturation of the EV-bearing proteins.
Conclusion: These data suggest that EVs (especially, the protein components) secreted by LPS inhalation are a key intercellular communicator in the development of airway immune dysfunction to inhaled LPS-containing allergens.