eprintid: 10204319 rev_number: 7 eprint_status: archive userid: 699 dir: disk0/10/20/43/19 datestamp: 2025-02-05 11:19:27 lastmod: 2025-02-05 11:19:27 status_changed: 2025-02-05 11:19:27 type: article metadata_visibility: show sword_depositor: 699 creators_name: Bove, Camilla creators_name: Arcangeli, Silvia creators_name: Falcone, Laura creators_name: Camisa, Barbara creators_name: El Khoury, Rita creators_name: Greco, Beatrice creators_name: De Lucia, Anna creators_name: Bergamini, Alice creators_name: Bondanza, Attilio creators_name: Ciceri, Fabio creators_name: Bonini, Chiara creators_name: Casucci, Monica title: CD4 CAR-T cells targeting CD19 play a key role in exacerbating cytokine release syndrome, while maintaining long-term responses ispublished: pub divisions: UCL divisions: B02 divisions: C10 divisions: D19 divisions: G98 note: This is an open access article distributed in accordance with the Creative Commons Attribution 4.0 Unported (CC BY 4.0) license, which permits others to copy, redistribute, remix, transform and build upon this work for any purpose, provided the original work is properly cited, a link to the licence is given, and indication of whether changes were made. See https://creativecommons.org/licenses/by/4.0/. abstract: Background To date, T cells redirected with CD19-specific chimeric antigen receptors (CAR) have gained impressive success in B-cell malignancies. However, treatment failures are common and the occurrence of severe toxicities, such as cytokine release syndrome (CRS), still limits the full exploitation of this approach. Therefore, the development of cell products with improved therapeutic indexes is highly demanded. Methods In this project, we investigated how CD4 and CD8 populations cooperate during CD19 CAR-T cell responses and what is their specific role in CRS development. To this aim, we took advantage of immunodeficient mice reconstituted with a human immune system (HuSGM3) and engrafted with the B-cell acute lymphoblastic leukemia cell line NALM-6, a model that allows to thoroughly study efficacy and toxicity profiles of CD19 CAR-T cell products. Results CD4 CAR-T cells showed superior proliferation and activation potential, which translated into stronger stimulation of myeloid cells, the main triggers of adverse events. Accordingly, toxicity assessment in HuSGM3 mice identified CD4 CAR-T cells as key contributors to CRS development, revealing a safer profile when they harbor CARs embedded with 4-1BB, rather than CD28. By comparing differentially co-stimulated CD4:CD8 1:1 CAR-T cell formulations, we observed that CD4 cells shape the overall expansion kinetics of the infused product and are crucial for maintaining long-term responses. Interestingly, the combination of CD4.BBz with CD8.28z CAR-T cells resulted in the lowest toxicity, without impacting antitumor efficacy. Conclusions Taken together, these data point out that the rational design of improved adoptive T-cell therapies should consider the biological features of CD4 CAR-T cells, which emerged as crucial for maintaining long-term responses but also endowed by a higher toxic potential. date: 2023-01 date_type: published publisher: BMJ official_url: https://doi.org/10.1136/jitc-2022-005878 oa_status: green full_text_type: pub language: eng primo: open primo_central: open_green verified: verified_manual elements_id: 2358036 doi: 10.1136/jitc-2022-005878 lyricists_name: Bove, Camilla lyricists_id: CBOVE38 actors_name: Bove, Camilla actors_id: CBOVE38 actors_role: owner full_text_status: public publication: Journal for ImmunoTherapy of Cancer volume: 11 number: 1 article_number: e005878 issn: 2051-1426 citation: Bove, Camilla; Arcangeli, Silvia; Falcone, Laura; Camisa, Barbara; El Khoury, Rita; Greco, Beatrice; De Lucia, Anna; ... Casucci, Monica; + view all <#> Bove, Camilla; Arcangeli, Silvia; Falcone, Laura; Camisa, Barbara; El Khoury, Rita; Greco, Beatrice; De Lucia, Anna; Bergamini, Alice; Bondanza, Attilio; Ciceri, Fabio; Bonini, Chiara; Casucci, Monica; - view fewer <#> (2023) CD4 CAR-T cells targeting CD19 play a key role in exacerbating cytokine release syndrome, while maintaining long-term responses. Journal for ImmunoTherapy of Cancer , 11 (1) , Article e005878. 10.1136/jitc-2022-005878 <https://doi.org/10.1136/jitc-2022-005878>. Green open access document_url: https://discovery.ucl.ac.uk/id/eprint/10204319/1/2023%2C%20Bove%20C%20at%20al%2C%20JITC.pdf