TY - JOUR N1 - © The Author(s), 2024. This is an Open Access article distributed under the terms of the Creative Commons Attribution Licence (CC BY 4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. https://creativecommons.org/licenses/by/4.0/ TI - Enhanced CD95 and interleukin 18 signalling accompany T cell receptor V?21.3+ activation in multi-inflammatory syndrome in children AV - public VL - 15 Y1 - 2024/05/18/ JF - Nature Communications A1 - Zhang, Zhenguang A1 - Kean, Iain RL A1 - Dratva, Lisa M A1 - Clark, John A A1 - Syrimi, Eleni A1 - Khan, Naeem A1 - Daubney, Esther A1 - White, Deborah A1 - O'Neill, Lauran A1 - Chisholm, Catherine A1 - Payne, Caroline A1 - Benkenstein, Sarah A1 - Kupiec, Klaudia A1 - Galassini, Rachel A1 - Wright, Victoria A1 - Winmill, Helen A1 - Robbins, Ceri A1 - Brown, Katherine A1 - Ramnarayan, Padmanabhan A1 - Scholefield, Barnaby A1 - Peters, Mark A1 - Klein, Nigel A1 - Montgomery, Hugh A1 - Meyer, Kerstin B A1 - Teichmann, Sarah A A1 - Bryant, Clare A1 - Taylor, Graham A1 - Pathan, Nazima KW - Adaptive immunity KW - Inflammatory diseases KW - SARS-CoV-2 KW - Viral infection N2 - Multisystem inflammatory syndrome in children is a post-infectious presentation SARS-CoV-2 associated with expansion of the T cell receptor V?21.3+ T-cell subgroup. Here we apply muti-single cell omics to compare the inflammatory process in children with acute respiratory COVID-19 and those presenting with non SARS-CoV-2 infections in children. Here we show that in Multi-Inflammatory Syndrome in Children (MIS-C), the natural killer cell and monocyte population demonstrate heightened CD95 (Fas) and Interleuking 18 receptor expression. Additionally, TCR V?21.3+ CD4+ T-cells exhibit skewed differentiation towards T helper 1, 17 and regulatory T cells, with increased expression of the co-stimulation receptors ICOS, CD28 and interleukin 18 receptor. We observe no functional evidence for NLRP3 inflammasome pathway overactivation, though MIS-C monocytes show elevated active caspase 8. This, coupled with raised IL18 mRNA expression in CD16- NK cells on single cell RNA sequencing analysis, suggests interleukin 18 and CD95 signalling may trigger activation of TCR V?21.3+ T-cells in MIS-C, driven by increased IL-18 production from activated monocytes and CD16- Natural Killer cells. ID - discovery10192583 UR - https://doi.org/10.1038/s41467-024-48699-y PB - Springer Science and Business Media LLC SN - 2041-1723 ER -