Human γδ T cells in diverse tissues exhibit site-specific maturation dynamics across the lifespan

During ontogeny, γδ T cells emerge from the thymus and directly seed peripheral tissues for in situ immunity, though their functional role in humans is largely defined from blood. Here, we analyzed the phenotype, transcriptome, function, and repertoire of human γδ T cells in blood, mucosal and lymphoid tissues from 176 donors across the lifespan, revealing distinct profiles in children compared to adults. In early life, clonally diverse Vd1 subsets predominate across blood and tissues, comprising naïve and differentiated effector and tissue repair functions, while cytolytic Vd2 subsets populate blood, spleen and lungs. Over age, both subsets exhibit clonal expansions disseminated across sites and express elevated cytolytic signatures. In adults, Vd2 cells predominate in blood, while Vd1 cells are enriched across tissues and express residency profiles. These results indicate that antigenic exposures over childhood drive the functional evolution and tissue compartmentalization of γδ T cells, leading to age-dependent roles in immunity. Adult and pediatric tissues were processed to a single cell suspension as described in the methods. Gd T cells were isolated by fluorescence-activated cellular sorting (FACS). DNA was isolated from sorted cell pellets using the DNA micro kit (Qiagen) and DNA concentrations were assessed using the NanoDrop (Thermo Scientific). TCRγ and TCRα/δ chains were amplified and sequenced to the survey-level by Adaptive Biotechnologies (Seattle, WA) using the ImmunoSEQ™ assay and their preprocessing pipeline which also removes PCR and sequencing errors. *************************************************************** Adaptive Biotechnologies does not release raw data. ***************************************************************