Longitudinal Flow Cytometric Profiling of CAR-T and Endogenous T Cells Following CD19 CAR-T Therapy
4 affiliations
- 1Department of Laboratory Medicine, Seoul St. Mary’s Hospital, College of Medicine, The Catholic University of Korea, Seoul 06591, Republic of Korea
- 2Department of Medical and Biological Sciences, Songeui Campus, The Catholic University of Korea, Seoul 06591, Republic of Korea
- 3Department of Pediatrics, Seoul St. Mary’s Hospital, College of Medicine, The Catholic University of Korea, Seoul 06591, Republic of Korea
- 4Department of Hematology, Catholic Hematology Hospital and Leukemia Research Institute, Seoul St. Mary’s Hospital, College of Medicine, The Catholic University of Korea, Seoul 06591, Republic of Korea
Abstract
Background/Objectives: Longitudinal monitoring after CD19-directed chimeric antigen receptor (CAR) T-cell therapy primarily focuses on CAR-T-cell expansion. However, comprehensive immunophenotypic characterization of both CAR-T and endogenous T cells remains limited. We investigated longitudinal immune dynamics following tisagenlecleucel treatment using multiparameter flow cytometry. Methods: Nineteen patients with relapsed or refractory B-cell malignancies (11 diffuse large B-cell lymphoma and eight B-cell acute lymphoblastic leukemia) receiving tisagenlecleucel were prospectively enrolled. Serial peripheral blood samples collected during the first 28 days after infusion were analyzed for CAR-T-cell kinetics, differentiation status, activation and exhaustion marker expression, longitudinal phenotypic changes, as well as associations with treatment response and immune-related toxicities. Results: CAR-T-cell expansion predominantly peaked on day 7 after infusion. However, in several patients with B-cell acute lymphoblastic leukemia, delayed peak expansion was observed. At peak expansion, CAR-T-cells were enriched for a central memory phenotype and exhibited significantly higher HLA-DR and PD-1 expression than endogenous T cells. During follow-up, the proportion of central memory T-cells progressively declined, whereas the proportion of terminal effector T-cells increased, which was accompanied by reduced expression of HLA-DR, PD-1, and TIGIT. Despite the distinct activation profiles, CAR-T and endogenous T-cells displayed broadly similar differentiation patterns. Exploratory analyses further demonstrated higher absolute CAR-T-cell counts in patients who developed immune effector cell-associated neurotoxicity syndrome. Conclusions: This clinically applicable approach provides immunophenotypic information beyond CAR-T-cell enumeration alone and may facilitate biomarker discovery and longitudinal immune monitoring in patients receiving CAR-T-cell therapy.
Related
- Cancer type-specific profiling of chromatin regulator mutations identifies recurrent and co-occurring gene sets associated with improved survival following immune checkpoint therapy
- Longitudinal Multi-omics Reveals Persistent Gut Microbial and Metabolic Dysbiosis Following Anti-Tuberculosis Therapy
- In Vivo Dynamics of Immunoregulatory Lymphocyte Reconstitution: A Seven-year Longitudinal Study of Sustained Remission in Class IV Lupus Nephritis Following Rituximab Therapy
- PO117 | LONGITUDINAL THROMBIN GENERATION PROFILING IN A PATIENT WITH SEVERE HEMOPHILIA A DURING ANTITHROMBIN-LOWERING THERAPY, CANCER, AND MAJOR SURGERY
- Longitudinal CT-derived muscle-fat-bone remodeling following androgen deprivation therapy initiation in prostate cancer.
BibTeX
@article{jee2026longitudinal,
title = {{Longitudinal Flow Cytometric Profiling of CAR-T and Endogenous T Cells Following CD19 CAR-T Therapy}},
author = {Sungyu Jee and Taewon Kang and Hyunjoo Bae and Takho Kang and Jin Jung and Yonggoo Kim and Myungshin Kim and Jae Won Yoo and Gi-June Min and Dong Wook Jekarl and Jong-Mi Lee},
journal = {Cancers},
year = {2026},
month = oct,
doi = {10.3390/cancers18203374},
url = {https://www.mdpi.com/2072-6694/18/20/3374},
note = {CC BY 4.0},
}
RIS
TY - JOUR
TI - Longitudinal Flow Cytometric Profiling of CAR-T and Endogenous T Cells Following CD19 CAR-T Therapy
AU - Sungyu Jee
AU - Taewon Kang
AU - Hyunjoo Bae
AU - Takho Kang
AU - Jin Jung
AU - Yonggoo Kim
AU - Myungshin Kim
AU - Jae Won Yoo
AU - Gi-June Min
AU - Dong Wook Jekarl
AU - Jong-Mi Lee
PY - 2026
DA - 2026/10/01
JO - Cancers
DO - 10.3390/cancers18203374
UR - https://www.mdpi.com/2072-6694/18/20/3374
AB - Background/Objectives: Longitudinal monitoring after CD19-directed chimeric antigen receptor (CAR) T-cell therapy primarily focuses on CAR-T-cell expansion. However, comprehensive immunophenotypic characterization of both CAR-T and endogenous T cells remains limited. We investigated longitudinal immune dynamics following tisagenlecleucel treatment using multiparameter flow cytometry. Methods: Nineteen patients with relapsed or refractory B-cell malignancies (11 diffuse large B-cell lymphoma and eight B-cell acute lymphoblastic leukemia) receiving tisagenlecleucel were prospectively enrolled. Serial peripheral blood samples collected during the first 28 days after infusion were analyzed for CAR-T-cell kinetics, differentiation status, activation and exhaustion marker expression, longitudinal phenotypic changes, as well as associations with treatment response and immune-related toxicities. Results: CAR-T-cell expansion predominantly peaked on day 7 after infusion. However, in several patients with B-cell acute lymphoblastic leukemia, delayed peak expansion was observed. At peak expansion, CAR-T-cells were enriched for a central memory phenotype and exhibited significantly higher HLA-DR and PD-1 expression than endogenous T cells. During follow-up, the proportion of central memory T-cells progressively declined, whereas the proportion of terminal effector T-cells increased, which was accompanied by reduced expression of HLA-DR, PD-1, and TIGIT. Despite the distinct activation profiles, CAR-T and endogenous T-cells displayed broadly similar differentiation patterns. Exploratory analyses further demonstrated higher absolute CAR-T-cell counts in patients who developed immune effector cell-associated neurotoxicity syndrome. Conclusions: This clinically applicable approach provides immunophenotypic information beyond CAR-T-cell enumeration alone and may facilitate biomarker discovery and longitudinal immune monitoring in patients receiving CAR-T-cell therapy.
SN - 2072-6694
ER -