Lay summary
Dendritic cells (DC) are rare immune cells necessary for the initiation of all immune responses. DC vary in phenotype depending on the tissue of origin, but it is presently unknow whether this variability may affect their capacity to initiate different types of immune responses.
We have discovered that the Th2 cytokine IL-13 is produced in skin but not in other tissues at steady-state, and is required for the full development of skin DC. In this application we propose to build on our initial observations that DC exposed to IL-13 become less efficient at initiating anti-microbial inflammatory responses while their capacity to initiate allergic responses is increased. We will use cellular, molecular and whole animal models to test the hypothesis that steady-state IL-13 in skin suppresses potentially damaging Th17 inflammation driven by commensal microorganisms, and that the consequence of such anti-inflammatory function is an increased vulnerability to allergic sensitisation.