eprintid: 10204062 rev_number: 11 eprint_status: archive userid: 699 dir: disk0/10/20/40/62 datestamp: 2025-01-29 10:43:16 lastmod: 2025-06-06 16:07:48 status_changed: 2025-01-29 10:43:16 type: article metadata_visibility: show sword_depositor: 699 creators_name: Ward, Alexander creators_name: Jose, des Las Heras creators_name: Eric, Schirmer creators_name: Fassati, Ariberto title: Memory CD4+ T Cells Sequentially Restructure Their 3D Genome During Stepwise Activation ispublished: pub divisions: UCL divisions: B02 divisions: C10 divisions: D15 keywords: 3D-genome organization, memory CD4+ T cells, sequential immune activation, gene expression regulation, Hi-C, IL-2, enhancer–promoter interactions, primed/de-primed genes note: © 2025 Ward, de las Heras, Schirmer and Fassati. This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY). The use, distribution or reproduction in other forums is permitted, provided the original author(s) and the copyright owner(s) are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. No use, distribution or reproduction is permitted which does not comply with these terms. abstract: BACKGROUND: CD4+ T cells are a highly differentiated cell type that maintain enough transcriptomic plasticity to cycle between activated and memory statuses. How the 1D chromatin state and 3D chromatin architecture support this plasticity is under intensive investigation. METHODS: Here, we wished to test a commercially available in situ Hi-C kit (Arima Genomics Inc.) to establish whether published performance on limiting cell numbers from clonal cell lines copies across to a primary immune cell type. We achieved comparable contact matrices from 50,000, 250,000, and 1,000,000 memory CD4+ T-cell inputs. We generated multiple Hi-C and RNA-seq libraries from the same biological blood donors under three separate conditions: unstimulated fresh ex vivo, IL-2-only stimulated, and T cell receptor (TCR)+CD28+IL-2-stimulated, conferring increasingly stronger activation signals. We wished to capture the magnitude and progression of 3D chromatin shifts and correlate these to expression changes under the two stimulations. RESULTS: Although some genome organization changes occurred concomitantly with changes in gene expression, at least as many changes occurred without corresponding changes in expression. Counter to the hypothesis that topologically associated domains (TADs) are largely invariant structures providing a scaffold for dynamic looping contacts between enhancers and promotors, we found that there were at least as many dynamic TAD changes. Stimulation with IL-2 alone triggered many changes in genome organization, and many of these changes were strengthened by additional TCR and CD28 co-receptor stimulation. CONCLUSIONS: This suggests a stepwise process whereby mCD4+ T cells undergo sequential buildup of 3D architecture induced by distinct or combined stimuli likely to “prime” or “deprime” them for expression responses to subsequent TCR-antigen ligation or additional cytokine stimulation. date: 2025-02-13 date_type: published publisher: Frontiers Media S.A. official_url: https://doi.org/10.3389/fcell.2025.1514627 oa_status: green full_text_type: pub language: eng primo: open primo_central: open_green verified: verified_manual elements_id: 2356542 doi: 10.3389/fcell.2025.1514627 lyricists_name: Fassati, Ariberto lyricists_id: AFASS84 actors_name: Fassati, Ariberto actors_id: AFASS84 actors_role: owner funding_acknowledgements: MR/W001241/1 [Medical Research Council]; 226791 [Wellcome Trust] full_text_status: public publication: Frontiers in Cell and Developmental Biology volume: 13 article_number: 1514627 citation: Ward, Alexander; Jose, des Las Heras; Eric, Schirmer; Fassati, Ariberto; (2025) Memory CD4+ T Cells Sequentially Restructure Their 3D Genome During Stepwise Activation. Frontiers in Cell and Developmental Biology , 13 , Article 1514627. 10.3389/fcell.2025.1514627 <https://doi.org/10.3389/fcell.2025.1514627>. Green open access document_url: https://discovery.ucl.ac.uk/id/eprint/10204062/1/Fassati_fcell-2-1514627.pdf