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Dienz, O.

Publications and source records attributed to Dienz, O..

2 recordsLinked to original sources

Mapping the developmental trajectories of SAP-dependent innate-like gamma delta (γδ) T cells

During thymic development, most {gamma}{delta} T cells acquire innate-like characteristics that are critical for their function in tumor surveillance, infectious disease, and tissue repair. The mechanisms, however, that regulate {gamma}{delta} T cell developmental programming remain unclear. Recently, we demonstrated that the SLAM-SAP signaling pathway regulates the development and function of multiple innate-like {gamma}{delta} T cell subsets. Here, we used a single-cell proteogenomics approach to identify SAP-dependent developmental checkpoints and to define the SAP-dependent {gamma}{delta} TCR repertoire. SAP deficiency resulted in both a significant loss of an immature Gzma+Blk+Etv5+Tox2+{gamma}{delta}T17 precursor population, and a significant increase in Cd4+Cd8+ Rorc+Ptcra+Rag1+ thymic {gamma}{delta} T cells. SAP-dependent diversion of embryonic day 17 thymic {gamma}{delta} T cell clonotypes into the {beta} T cell developmental pathway was associated with a decreased frequency of mature clonotypes in neonatal thymus, and an altered {gamma}{delta} TCR repertoire in the periphery. Finally, we identify TRGV4/TRAV13-4(DV7)-expressing T cells as a novel, SAP-dependent V{gamma}4 {gamma}{delta}T1 subset. Together, the data suggest that SAP-dependent {gamma}{delta}/{beta} T cell lineage commitment regulates {gamma}{delta} T cell developmental programming and shapes the {gamma}{delta} TCR repertoire. O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=142 SRC="FIGDIR/small/575073v3_ufig1.gif" ALT="Figure 1"> View larger version (43K): org.highwire.dtl.DTLVardef@1d8b5aeorg.highwire.dtl.DTLVardef@7fd02dorg.highwire.dtl.DTLVardef@13c5c76org.highwire.dtl.DTLVardef@1da72b1_HPS_FORMAT_FIGEXP M_FIG C_FIG

immunology↗

Critical role for Slam/SAP signaling in the thymic developmental programming of IL-17- and IFN-γ-producing γδ T cells

During thymic development, {gamma}{delta} T cells commit to either an IFN-{gamma}- or an IL-17-producing phenotype through mechanisms that remain unclear. Here, we investigated whether the SLAM/SAP signaling pathway played a role in the functional programming of thymic {gamma}{delta} T cells. Characterization of SLAM family receptor expression revealed that thymic {gamma}{delta} T cell subsets were each marked by distinct co-expression profiles of SLAMF1, SLAMF4, and SLAMF6. In the thymus, immature CD24hi V{gamma}1 and V{gamma}4 {gamma}{delta} T cells were largely contained within a SLAMF1+SLAMF6+ double positive (DP) population, while mature CD24low subsets were either SLAMF1+ or SLAMF6+ single positive (SP) cells. In the periphery, SLAMF1 and SLAMF6 expression on V{gamma}1, V{gamma}4, and V{gamma}6 T cells distinguished IL-17- and IFN-{gamma}-producing subsets, respectively. Disruption of SLAM family receptor signaling through deletion of SAP resulted in impaired thymic {gamma}{delta} T cell maturation at the CD24hiSLAMF1+SLAMF6+ DP stage that was associated with a decreased frequency of CD44+ROR{gamma}t+ {gamma}{delta} T cells. These defects were in turn associated with impaired {gamma}{delta} T cell IL-17 and IFN-{gamma} production in both the thymus as well as in peripheral tissues. The role for SAP was subset-specific, as V{gamma}1, V{gamma}4, V{gamma}5, but not V{gamma}6 subsets were SAP-dependent. Together, these data suggest that the SLAM/SAP signaling pathway regulates a critical checkpoint in the functional programming of IL-17 and IFN-{gamma}-producing {gamma}{delta} T cell subsets during thymic development.

immunology↗