The GM-CSF Released by Airway Epithelial Cells Orchestrates the Mucosal Adjuvant Activity of Flagellin.

In this study, we looked at how the airway epithelial cells (AECs) regulate the flagellin-dependent stimulation of Ag-specific CD4+ T cells and the Ab response in mice. Our results demonstrate that after sensing flagellin, AECs trigger the release of GM-CSF in a TLR5-dependent fashion and the doubling of the number of activated type 2 conventional dendritic cells (cDC2s) in draining lymph nodes. Furthermore, the neutralization of GM-CSF reduced cDC2s activation. This resulted in lower of Ag-specific CD4+ T cell count and Ab titers in mice. Our data indicate that during pulmonary immunization, the GM-CSF released by AECs orchestrates the cross-talk between cDC2s and CD4+ T cells and thus drives flagellin's adjuvant effect. PMID: 33008952 [PubMed - as supplied by publisher]
Source: Journal of Immunology - Category: Allergy & Immunology Authors: Tags: J Immunol Source Type: research