The human skin harbors a heterogenous pool of cytotoxic tissue-resident memory T (TRM) cells seeded during infections and inflammation. TRM cells are retained at the site of viral infections and provide local immunity. These cells persist for years in the skin after bone marrow transplantation but circulating ex-TRM cells indicate several potential fates. Here, we explored the clonal relationships between human T cells in different skin compartments and circulation. 10x Genomics 5 prime immune profiling coupled with feature barcoding technology was employed to investigate the clonal relationship, transcriptomic and proteomic profiles of single T cells sorted from blood, subcutis, dermis, and epidermis. A few CD8+ TRM cell-clones dominate epidermis and cytotoxic CD8+CD103+ CD49a+ showed the least diverse T cell receptor (TCR) repertoire. Clonal overlap was found between all three compartments: circulating blood T cells, dermal and epidermal TRM cells. The highest degree of overlap was detected between epidermis and dermis. Clones overlapping was scarce between blood and highly abundant epidermal clones. Our results suggest that lowly abundant skin clonotypes have a circulatory counterpart, which can react to reinfection at secondary sides, whereas highly abundant epidermal clones might be skin specific.

ESDR015 - Clonal sharing of skin T cells within different skin compartments and blood

The scientific meeting of the European Society for Dermatological Research (ESDR) is held yearly, usually in September. With an international attendance of more than 1000 skin scientists from around the globe, the four-day event includes short oral presentations from peer-reviewed abstracts, keynote lectures from international experts, sponsored symposia, satellite programs, educational events as well as an important focus on posters, networking and building collaborations amongst scientists. For more information about this year’s meeting visit our website.