W151 - Identifying Distinct Subsets of Vγ5⁺ Epidermal Gamma Delta T Cells in Psoriasis Using Single-cell RNA Sequencing

Abstract Text: The prevalence of autoimmune skin disorders is increasing in the U.S., with 3.0% suffering from psoriasis in 2024. Human skin contains resident T cells, including epidermal gd and ab T cells and dermal gd and ab T cells. Dermal gd T cells are well known IL-17 producers that contribute to psoriasis however, less is known about the epidermal subset. Using murine models of IMQ-induced psoriasis, we examined the role of distinct subsets of gd T cells in the epidermis. We analyzed publicly available scRNA-seq data to assess whether epidermal γδ T cell populations have distinct roles in psoriasis. We identified five distinct epidermal γδ T cell clusters in murine control and imiquimod-treated skin samples. The genes that define each cluster represent functional groups as such: cluster 1 Th1 responses (CD27, CD96, and IL12RB2), cluster 2 neuronal communication (INSR, NRCAM, and NPY1R), cluster 3 T regulatory function (KDM5D, Kat5, CD24a, and Itgae) cluster 4 T cell proliferation (Dcaf6, CD7, CD94, and CD247), and cluster 5 Th17 responses (IL17F, Rora). We are validating each epidermal γδ T cell cluster in vivo in an IMQ-induced psoriasis mouse model of disease using immunofluorescence and flow cytometry, Understanding the functions of epidermal γδ T cell clusters in psoriasis may reveal novel ways to control psoriasis.