?dT cell Interactions within the Tissue Ecosystem Network [bulk RNAseq]

Numerous lymphocytes seed the body surfaces of metazoans promoting tissue protection and integrity. These tissue-resident populations differ substantially from circulating lymphocytes, as they adopt a unique phenotype and do not recirculate. They span the innate-adaptive continuum, ranging from innate lymphoid cells (ILCs) to unconventional T cells (NKT, MAIT, ?dT cells and IELs) and tissue-resident memory (TRM) T cells, and while differ in the particulars of their biology, all contribute to barrier immunity, tissue homeostasis, and immune regulation. Although they share the same microenvironment, little is known about how these tissue-resident lymphocyte populations interact with each other and with the non-lymphoid cellular environment. As such, there is an emerging view of tissues as varied '' ecosystems '', whereby protection against inflammatory challenges is orchestrated through the interplay between tissue-resident and infiltrating-lymphocyte subtypes. In mice, barrier tissues are populated during early life by innate-like ?dT lymphocytes. These cells provide tissue protection, including limiting conventional T cell-driven inflammation. Therefore, elucidating the contributions of tissue-resident T cells, particularly ?dT cells, to the basic pathophysiology of tissue function and protection against infection, inflammation, and cancer is a priority. To this aim, we have induced allergic contact dermatitis in the back skin of different strains and we analyzed the behavior of ?dT cells Overall design: Examination of ?dT cells in challenged and unchallanged mice in WT and IFNgRIKO