Bidirectional crosstalk between gut and lung immunity: Migration of gut IgA plasma cells during allergic asthma 9176

Abstract Description The gut plays a central role in systemic immunity, serving as a key interface with the immune system. Gut-derived immune cells significantly influence various diseases, but the mechanisms linking intestinal immune cells and lung responses within the gut-lung axis remain unclear. To address this, we used an allergic asthma model to investigate the interaction between airway inflammation and gut mucosal immunity. Allergic asthma induced a marked reduction of IgA plasma cells in the intestine, which coincided with their accumulation in the lungs. This reduction was attributed to the migration of IgA plasma cells from the gut to the lungs, evidenced by the presence of adoptively transferred IgA plasma cells and the detection of gut pathogen-specific IgA antibody-secreting cells (ASCs) in the lungs of asthmatic mice following gut pathogen infection. Inflammatory mediators, such as IL-5 and CCL20, induced by allergic airway inflammation, were identified as critical drivers of this migration. In the lungs, the migrated IgA plasma cells produced IL-10, exerting immune regulatory functions. However, their reduction in the gut impaired specific IgA responses, increasing susceptibility to gut inflammation. These findings reveal a novel mechanism illustrating the bidirectional impact of allergic airway inflammation on gut and lung immunity. This underscores the intricate interplay within the gut-lung axis and its profound implications for immune regulation and disease pathogenesis. Funding Sources Supported by Basic Science Research Program through the National Research Foundation of Korea (NRF) funded by the Korea government NRF-2022R1C1C100325614; NRF-2022R1C1C1009333 Topic Categories Mucosal and Regional Immunology (MUC)