A Single-cell Transcriptomic Profiling Reveals the Effects of Chronic House Dust Mite Exposure on the Murine Lung Microenvironment

House dust mite (HDM) is a common environmental aeroallergen linked to the development of allergic airway inflammation and asthma. While the effects of acute HDM exposure on T helper 2 (Th2)-driven allergic responses and pulmonary eosinophilia are well established in murine models, the impact of chronic HDM exposure on other inflammatory responses, particularly those involving interleukin-1β (IL-1β) and neutrophilia, remains poorly defined. To address this gap, we performed single-cell RNA sequencing (scRNA-seq) to examine lung immune responses in wild-type and IL-1β-deficient mice following chronic HDM exposure. Our data reveal that HDM promotes the recruitment of diverse immune cell populations in the lungs, including neutrophils, alternatively activated (M2-polarized) macrophages, B-2 (follicular) B cells, and multiple CD4 regulatory and effector T cell subsets. IL-1β signaling was essential for supporting neutrophil and Th17 responses, whereas its absence enhanced Th2-skewed immune polarization in the lung. These immune populations differently contribute to the development or resolution of lung inflammation in an IL-1β-dependent or -independent manner. This study offers a detailed characterization of the cellular and molecular alterations induced by chronic HDM exposure and reveals previously unrecognized roles for IL-1β in orchestrating chronic lung inflammation.