{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,12,6]],"date-time":"2025-12-06T21:49:29Z","timestamp":1765057769530,"version":"build-2065373602"},"reference-count":26,"publisher":"MDPI AG","issue":"14","license":[{"start":{"date-parts":[[2022,7,8]],"date-time":"2022-07-08T00:00:00Z","timestamp":1657238400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"NIHR GOSH BRC"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["IJMS"],"abstract":"<jats:p>Chimeric antigen receptor (CAR) T cell therapy is an innovative immunotherapy for treating cancers in both children and adults with proven utility in numerous clinical trials. Significantly, some CAR T cell therapies have now been approved by relevant national regulatory bodies across numerous countries for clinical therapeutic use outside of clinical trials. One such recently licensed product is tisagenlecleucel, a CAR T therapy approved for the treatment of B-cell acute lymphoblastic leukemia (B-ALL) using autologous T cells from the patient. The genetically engineered T cells target a protein called CD19, common to B cells, through a CAR incorporating a 4-1BB costimulatory domain to improve response. Since tisagenlecleucel is now a standard of care treatment for B-ALL, it is clinically essential to be able to accurately monitor these CAR T cells in patients. Assessment of the copy number variant (CNV) of the CAR T cell products allows this within a clinically acceptable timeframe for optimal patient benefit. However, no standardized method with high reproducibility and efficiency has been described within a routine clinical laboratory setting. Here, we demonstrated a novel digital droplet PCR (ddPCR)-based methodology for the study of CNV (ddPCR-CNV) in 4-1BB CD19-specific CAR T cells with universal applicability across clinical diagnostic laboratories.<\/jats:p>","DOI":"10.3390\/ijms23147573","type":"journal-article","created":{"date-parts":[[2022,7,8]],"date-time":"2022-07-08T11:37:08Z","timestamp":1657280228000},"page":"7573","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":6,"title":["Clinically Applicable Assessment of Tisagenlecleucel CAR T Cell Treatment by Digital Droplet PCR for Copy Number Variant Assessment"],"prefix":"10.3390","volume":"23","author":[{"given":"Soragia Athina","family":"Gkazi","sequence":"first","affiliation":[{"name":"SIHMDS-Haematology, Great Ormond Street Hospital for Children NHS Foundation Trust, London WC1N 3HJ, UK"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Emma","family":"Gravett","sequence":"additional","affiliation":[{"name":"SIHMDS-Haematology, Great Ormond Street Hospital for Children NHS Foundation Trust, London WC1N 3HJ, UK"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Carla","family":"Bautista","sequence":"additional","affiliation":[{"name":"SIHMDS-Haematology, Great Ormond Street Hospital for Children NHS Foundation Trust, London WC1N 3HJ, UK"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1573-2506","authenticated-orcid":false,"given":"Jack","family":"Bartram","sequence":"additional","affiliation":[{"name":"Department of Haematology, Great Ormond Street Hospital for Children NHS Foundation Trust, London WC1N 3HJ, UK"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Sara","family":"Ghorashian","sequence":"additional","affiliation":[{"name":"Department of Haematology, Great Ormond Street Hospital for Children NHS Foundation Trust, London WC1N 3HJ, UK"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2650-2848","authenticated-orcid":false,"given":"Stuart Paul","family":"Adams","sequence":"additional","affiliation":[{"name":"SIHMDS-Haematology, Great Ormond Street Hospital for Children NHS Foundation Trust, London WC1N 3HJ, UK"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2022,7,8]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1408","DOI":"10.1038\/s41591-019-0549-5","article-title":"Enhanced CAR T cell expansion and prolonged persistence in pediatric patients with ALL treated with a low-affinity CD19 CAR","volume":"25","author":"Ghorashian","year":"2019","journal-title":"Nat. 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