Chimeric Antigen Receptor T-cell Therapy Research Articles

Evaluation of Anti-CAR Linker mAbs for CAR T Monitoring after BiTEs/bsAbs and CAR T-Cell Pretreatment.

For the monitoring of chimeric antigen receptor (CAR) T-cell therapies, antigen-based CAR detection methods are usually applied. However, for each target-antigen, a separate detection system is required. Furthermore, when monitored CAR T-cells in the blood of patients treated with bispecific antibodies or T-cell engagers (bsAbs/BiTEs) recognize the same antigen, these methods produce false-positive results in clinical diagnostics. Anti-CAR-linker monoclonal antibodies (mAbs) targeting the linker sequence between the variable domains of the antigen binding CAR fragment promise a universal and unbiased CAR detection. To test this, we analyzed clinical specimens of all BCMA- and CD19-targeting CAR T-cell products currently approved for clinical use. We found a highly specific and sensitive CAR detection using anti-CAR-linker mAb in blood cells from patients treated with Ide-cel, Tisa-cel, Axi-cel, Brexu-cel, and Liso-cel. For Ide-cel and Tisa-cel, the sensitivity was significantly lower compared to that for antigen-based CAR detection assays. Strikingly, the specificity of anti-CAR linker mAb was not affected by the simultaneous presence of bispecific blinatumomab or teclistamab for Axi-cel, Brexu-cel, Liso-cel, or Ide-cel, respectively. Cilta-cel (containing a monomeric G4S-CAR linker) could not be detected by anti-CAR linker mAb. In conclusion, anti-CAR-linker mAbs are highly specific and useful for CAR T-cell monitoring but are not universally applicable.

Improved outcome of COVID-19 over time in patients treated with CAR T-cell therapy: Update of the European COVID-19 multicenter study on behalf of the European Society for Blood and Marrow Transplantation (EBMT) Infectious Diseases Working Party (IDWP) and the European Hematology Association (EHA) Lymphoma Group

COVID-19 has been associated with high mortality in patients treated with Chimeric Antigen Receptor (CAR) T-cell therapy for hematologic malignancies. Here, we investigated whether the outcome has improved over time with the primary objective of assessing COVID-19-attributable mortality in the Omicron period of 2022 compared to previous years. Data for this multicenter study were collected using the MED-A and COVID-19 report forms developed by the EBMT. One-hundred-eighty patients were included in the analysis, 39 diagnosed in 2020, 35 in 2021 and 106 in 2022. The median age was 58.9 years (min-max: 5.2–78.4). There was a successive decrease in COVID-19-related mortality over time (2020: 43.6%, 2021: 22.9%, 2022: 7.5%) and in multivariate analysis year of infection was the strongest predictor of survival (p = 0.0001). Comparing 2022 with 2020–2021, significantly fewer patients had lower respiratory symptoms (21.7% vs 37.8%, p = 0.01), needed oxygen support (25.5% vs 43.2%, p = 0.01), or were admitted to ICU (5.7% vs 33.8%, p = 0.0001). Although COVID-19-related mortality has decreased over time, CAR T-cell recipients remain at higher risk for complications than the general population. Consequently, vigilant monitoring for COVID-19 in patients undergoing B-cell-targeting CAR T-cell treatment is continuously recommended ensuring optimal prevention of infection and advanced state-of-the art treatment when needed.

Anti-BCMA/GPRC5D bispecific CAR T cells in patients with relapsed or refractory multiple myeloma: a single-arm, single-centre, phase 1 trial

Some challenges still exist with single-target B-cell maturation antigen (BCMA) chimeric antigen receptor (CAR) T-cell therapies due to variable or negative BCMA expression, although they have yielded remarkable efficacy in relapsed or refractory multiple myeloma. We developed anti-BCMA/GPRC5D bispecific CARs to mitigate the limitations and potentiate the functions of CAR T cells. This single-arm, phase 1 trial was conducted at the Affiliated Hospital of Xuzhou Medical University (Xuzhou, China). The trial enrolled patients aged 18-75 years with relapsed or refractory multiple myeloma and an Eastern Cooperative Oncology Group performance status of 0-3. Anti-BCMA/GPRC5D bispecific CAR T cells were administered at 0·5 × 106, 1·0 × 106, 2·0 × 106, and 4·0 × 106 CAR T cells per kg in the dose-escalation phase, with additional patients included at the dose selected for the dose-expansion phase. The primary endpoint was safety, which included dose-limiting toxicity and maximum tolerated dose. Activity was also evaluated as a secondary endpoint. The maximum tolerated dose was chosen for the dose-expansion phase. Safety and activity analyses were done in all patients who received anti-BCMA/GPRC5D bispecific CAR T cells as defined in the protocol. This trial is registered with ClinicalTrials.gov (NCT05509530) and is complete. Between Sept 1, 2022, and Nov 3, 2023, 24 patients were enrolled and underwent apheresis. Three patients were excluded after apheresis (two patients discontinued due to rapid disease progression and one patient was withdrawn because of failed manufacture of CAR T cells), so 21 patients were infused with anti-BCMA/GPRC5D bispecific CAR T cells. Median follow-up was 5·8 months (IQR 5·2-6·7). Median age was 62 years (IQR 56-67). Eight (38%) patients were male, and 13 (62%) female. All patients were Chinese. At the 4·0 × 106 CAR T cells per kg dose, two patients had dose-limiting toxicities, of whom one died of subarachnoid haemorrhage (which was not considered to be related to the study treatment). The maximum tolerated dose was identified as 2·0 × 106 CAR T cells per kg. The most common grade 3 or worse adverse events were haematological toxicities in 19 (90%) patients (except lymphopenia). 15 (71%) patients had cytokine release syndrome, of which all cases were grade 1 or 2. One case of grade 1 immune effector cell-associated neurotoxicity syndrome (ICANS) was observed in a patient who received 4·0 × 106 CAR T cells per kg. No ICANS or grade 3 or worse organ toxicities were observed in patients who received 0·5-2·0 × 106 CAR T cells per kg. The overall response rate was 86% (18 of 21 patients), with 13 (62%) patients having a complete response or better, and 17 (81%) patients having measurable residual disease negativity. Of the 12 patients who received 2·0 × 106 CAR T cells per kg (three in the dose-escalation phase and an addition nine in the dose-expansion phase), the overall response rate was 92% (11 of 12 patients) with nine (75%) patients having a complete response or better. Anti-BCMA/GPRC5D bispecific CAR T cells show a good safety profile and encouraging activity in patients with relapsed or refractory multiple myeloma. National Natural Science Foundation of China. For the Chinese translation of the abstract see Supplementary Materials section.

CAR T-cells targeting FGFR4 and CD276 simultaneously show potent antitumor effect against childhood rhabdomyosarcoma

Chimeric antigen receptor (CAR) T-cells targeting Fibroblast Growth Factor Receptor 4 (FGFR4), a highly expressed surface tyrosine receptor in rhabdomyosarcoma (RMS), are already in the clinical phase of development, but tumour heterogeneity and suboptimal activation might hamper their potency. Here we report an optimization strategy of the co-stimulatory and targeting properties of a FGFR4 CAR. We replace the CD8 hinge and transmembrane domain and the 4-1BB co-stimulatory domain with those of CD28. The resulting CARs display enhanced anti-tumor activity in several RMS xenograft models except for an aggressive tumour cell line, RMS559. By searching for a direct target of the RMS core-regulatory transcription factor MYOD1, we identify another surface protein, CD276, as a potential target. Bicistronic CARs (BiCisCAR) targeting both FGFR4 and CD276, containing two distinct co-stimulatory domains, have superior prolonged persistent and invigorated anti-tumor activities compared to the optimized FGFR4-specific CAR and the other BiCisCAR with the same 4-1BB co-stimulatory domain. Our study thus lays down the proof-of-principle for a CAR T-cell therapy targeting both FGFR4 and CD276 in RMS.

Outcomes of patients with R/R B-cell NHL and limited (

AbstractUnirradiated patients with relapsed/refractory (R/R) B-cell non-Hodgkin lymphoma (NHL) who undergo anti-CD19 chimeric antigen receptor T-cell therapy (CART) have a predominant localized pattern of relapse, the significance of which is heightened in individuals with limited/localized disease before CART. This study reports on the outcomes of patients with R/R NHL and limited (<5 involved sites) disease bridged with or without radiotherapy. A multicenter retrospective review of 150 patients with R/R NHL who received CART with <5 disease sites before leukapheresis was performed. Bridging treatment, if any, was administered between leukapheresis and CART infusion. Study end points included relapse-free survival (RFS), event-free survival (EFS), and overall survival. Before CART infusion, 48 patients (32%) received bridging radiotherapy (BRT), and 102 (68%) did not. The median follow-up was 21 months. After CART infusion, BRT patients had higher objective response (92% vs 78%; P = .046) and sustained complete response rates (54% vs 33%; P = .015). Local relapse in sites present before CART was lower in the BRT group (21% vs 46%; P = .003). BRT patients had improved 2-year RFS (53% vs 44%; P = .023) and 2-year EFS (37% vs 34%; P = .039) compared with patients who did not receive BRT. The impact of BRT was most prominent in patients who had ≤2 pre-CART involved disease sites, with 2-year RFS of 62% in patients who received BRT compared with 42% in those who did not (P = .002). BRT before CART for patients with limited (<5 involved disease sites) R/R NHL improves response rate, local control, RFS, and EFS without causing significant toxicities.

Persistent cytopenias after anti-BCMA CAR T-cell therapy are associated with reduced hematopoietic activity in posttreatment bone marrows.

We attempt to analyze bone marrow findings and correlation with cytopenia(s) after anti-B-cell maturation antigen (BCMA) chimeric antigen receptor (CAR) T-cell infusion in this study. Relevant clinicopathologic data, including complete blood counts, neutrophil counts, relevant therapy history, and pre- and posttherapy bone marrow evaluations, were studied in 12 patients who received anti-BCMA CAR T-cell therapy. Bone marrow findings after CAR T-cell therapy were available in 6 of 12 cases, 3 of which showed markedly hypocellular marrow with either markedly reduced or essentially absent hematopoiesis. One case showed a hypocellular marrow with trilineage hematopoiesis, while the remaining 2 cases showed persistent involvement by plasma cell myeloma. Reticulin stains did not reveal significant fibrosis. Ten patients had anemia, and 8 patients had leukopenia and thrombocytopenia at day 90 posttherapy. Long-term follow-up showed persistent disease in 10 of 12 cases. Prolonged cytopenias occur in most patients after BCMA CAR T-cell therapy with bone marrow evaluations demonstrating associated marked hypocellularity with minimal or no hematopoiesis without an increase in fibrosis.

An agent-based method to estimate 3D cell migration trajectories from 2D measurements: Quantifying and comparing T vs CAR-T 3D cell migration

Background and objective:Immune cell migration is one of the key features that enable immune cells to find invading pathogens, control tissue damage, and eliminate primary developing tumors. Chimeric antigen receptor (CAR) T-cell therapy is a novel strategy in the battle against various cancers. It has been successful in treating hematological tumors, yet it still faces many challenges in the case of solid tumors. In this work, we evaluate the three-dimensional (3D) migration capacity of T and CAR-T cells within dense collagen-based hydrogels. Quantifying three-dimensional (3D) cell migration requires microscopy techniques that may not be readily accessible. Thus, we introduce a straightforward mathematical model designed to infer 3D trajectories of cells from two-dimensional (2D) cell trajectories. Methods:We develop a 3D agent-based model (ABM) that simulates the temporal changes in the direction of migration with an inverse transform sampling method. Then, we propose an optimization procedure to accurately orient cell migration over time to reproduce cell migration from 2D experimental cell trajectories. With this model, we simulate cell migration assays of T and CAR-T cells in microfluidic devices conducted under hydrogels with different concentrations of type I collagen and validate our 3D cell migration predictions with light-sheet microscopy. Results:Our findings indicate that CAR-T cell migration is more sensitive to collagen concentration increases than T cells, resulting in a more pronounced reduction in their invasiveness. Moreover, our computational model reveals significant differences in 3D movement patterns between T and CAR-T cells. T cells exhibit migratory behavior in 3D whereas that CAR-T cells predominantly move within the XY plane, with limited movement in the Z direction. However, upon the introduction of a CXCL12 chemical gradient, CAR-T cells present migration patterns that closely resemble those of T cells. Conclusions:This framework demonstrates that 2D projections of 3D trajectories may not accurately represent real migration patterns. Moreover, it offers a tool to estimate 3D migration patterns from 2D experimental data, which can be easily obtained with automatic quantification algorithms. This approach helps reduce the need for sophisticated and expensive microscopy equipment required in laboratories, as well as the computational burden involved in producing and analyzing 3D experimental data.

Cytomegaloviral Infections in Recipients of Chimeric Antigen Receptor T-Cell Therapy: An Observational Study With Focus on Oncologic Outcomes.

Patients with B-cell lymphoma and acute lymphoblastic leukemia (ALL) who receive chimeric antigen receptor T-cell (CAR-T) therapy may experience clinically significant cytomegalovirus infection (CS-CMVi). However, risk factors for CS-CMVi are not well defined. The aims of our study were to identify risk factors for CS-CMVi and the association between CS-CMVi and nonrelapse mortality (NRM) in lymphoma and ALL patients after CAR-T therapy. We performed a retrospective single-center cohort analysis of CAR-T recipients between January 2018 and February 2021 for treatment of lymphoma and ALL. We collected data on demographics, oncologic history, CAR-T therapy-related complications, and infectious complications within 1 year of therapy. Of 230 patients identified, 22 (10%) had CS-CMVi. At 1 year following CAR-T therapy, 75 patients (33%) developed relapsed disease and 95 (41%) died; NRM at 1 year was 37%. On Cox regression analysis, Asian or Middle Eastern race (adjusted hazard ratio [aHR], 13.71 [95% confidence interval {CI}, 5.41-34.74]), treatment of cytokine release syndrome/immune effector cell-associated neurotoxicity syndrome with steroids (aHR, 6.25 [95% CI, 1.82-21.47]), lactate dehydrogenase at time of CAR-T therapy (aHR, 1.09 [95% CI, 1.02-1.16]), and CMV surveillance (aHR, 6.91 [95% CI, 2.77-17.25]) were independently associated with CS-CMVi. CS-CMVi was independently associated with NRM at 1 year after CAR-T therapy (odds ratio, 2.49 [95% CI, 1.29-4.82]). Further studies of immunologic correlatives and clinical trials to determine the efficacy of prophylactic strategies are needed to understand the role of CS-CMVi and post-CAR-T mortality.

The Role of Chimeric Antigen Receptor T-Cell Therapy in Immune-Mediated Neurological Diseases.

Despite the use of 'high efficacy' disease-modifying therapies, disease activity and clinical progression of different immune-mediated neurological diseases continue for some patients, resulting in accumulating disability, deteriorating social and mental health, and high economic cost to patients and society. Although autologous hematopoietic stem cell transplant is an effective treatment modality, it is an intensive chemotherapy-based therapy with a range of short- and long-term side-effects. Chimeric antigen receptor T-cell therapy (CAR-T) has revolutionized the treatment of B-cell and other hematological malignancies, conferring long-term remission for otherwise refractory diseases. However, the toxicity of this treatment, particularly cytokine release syndrome and immune effector cell-associated neurotoxicity syndrome, and the complexity of production necessitate the need for a high level of specialization at treating centers. Early-phase trials of CAR-T therapies in immune-mediated B cell driven conditions, such as systemic lupus erythematosus, neuromyelitis optica spectrum disorder and myasthenia gravis, have shown dramatic clinical response with few adverse events. Based on the common physiopathology, CAR-T therapy in other immune-mediated neurological disease, including multiple sclerosis, chronic inflammatory polyradiculopathy, autoimmune encephalitis, and stiff person syndrome, might be an effective option for patients, avoiding the need for long-term immunosuppressant medications. It may prove to be a more selective immunoablative approach than autologous hematopoietic stem cell transplant, with potentially increased efficacy and lower adverse events. In this review, we present the state of the art and future directions of the use of CAR-T in such conditions. ANN NEUROL 2024;96:441-452.

The Evolving Role of Bridging Therapy during CAR-T Therapy.

Chimeric antigen receptor (CAR) T-cell therapy has gained wide used across an array of hematologic malignancies. Though CAR T therapy has changed outcomes in the treatment of many malignancies its administration can be complicated by delays related to patient-related factors, social barriers, or insurance issues. Because of the lengthy process required to treat a patient with CAR T-cells, bridging therapy (BT), administered after leukapheresis but prior to CAR T infusion, has become an important component of safely administering CAR T therapy. Here we review data supporting the use of BT, factors to consider in patient selection, and types of available BT and rationale for choosing amongst them.

MRNA-Engineered CD5-CAR-γδTCD5- Cells for the Immunotherapy of T-Cell Acute Lymphoblastic Leukemia.

Clinical trials of Chimeric Antigen Receptor T-cell (CAR-T) therapy have demonstrated remarkable success in treating both solid tumors and hematological malignancies. Nanobodies (Nbs) have emerged as promising antigen-targeting domains for CARs, owing to their high specificity, robust stability, and strong affinity, leading to significant advancements in the field of Nb-CAR-T. In the realm of T-cell acute lymphoblastic leukemia (T-ALL) targets, CD5 stands out as a potentially excellent candidate for T-cell-based CAR therapy, due to its distinct expression on the surface of malignant T-ALL cells. To mitigate graft-versus-host disease associated with allogeneic CAR-T, γδT cells are selected and stimulated from peripheral blood mononuclear cells, and γδT cells are engineered via CRISPR/Cas9 to eliminate fratricide, enabling the creation of fratricide-resistant CAR-γδTCD5- cells. In vitro transcribed (IVT) mRNA is used to construct CAR-T, presenting a safer, faster, and cost-effective method compared to traditional viral vector approaches. In this study, a CD5-VHH library is constructed, and specific CD5-nanobodies are screened for subsequent use in CD5-CAR-γδTCD5- therapy. IVT-mRNA-CD5-CAR-γδTCD5- cells exhibited favorable functional characteristics and demonstrated antitumor efficacy against malignant T cell lines, underlining the potential for advancing mRNA-CD5-CAR-γδTCD5- therapy.

Advancements in Personalized CAR-T Therapy: Comprehensive Overview of Biomarkers and Therapeutic Targets in Hematological Malignancies.

Chimeric antigen receptor T-cell (CAR-T) therapy is a novel anticancer therapy using autologous or allogeneic T-cells. To date, six CAR-T therapies for specific B-cell acute lymphoblastic leukemia (B-ALL), non-Hodgkin lymphomas (NHL), and multiple myeloma (MM) have been approved by the Food and Drug Administration (FDA). Significant barriers to the effectiveness of CAR-T therapy include cytokine release syndrome (CRS), neurotoxicity in the case of Allogeneic Stem Cell Transplantation (Allo-SCT) graft-versus-host-disease (GVHD), antigen escape, modest antitumor activity, restricted trafficking, limited persistence, the immunosuppressive microenvironment, and senescence and exhaustion of CAR-Ts. Furthermore, cancer drug resistance remains a major problem in clinical practice. CAR-T therapy, in combination with checkpoint blockades and bispecific T-cell engagers (BiTEs) or other drugs, appears to be an appealing anticancer strategy. Many of these agents have shown impressive results, combining efficacy with tolerability. Biomarkers like extracellular vesicles (EVs), cell-free DNA (cfDNA), circulating tumor (ctDNA) and miRNAs may play an important role in toxicity, relapse assessment, and efficacy prediction, and can be implicated in clinical applications of CAR-T therapy and in establishing safe and efficacious personalized medicine. However, further research is required to fully comprehend the particular side effects of immunomodulation, to ascertain the best order and combination of this medication with conventional chemotherapy and targeted therapies, and to find reliable predictive biomarkers.

CD19-directed CART therapy for T-cell/histiocyte–rich large B-cell lymphoma

AbstractT-cell/histiocyte–rich large B-cell lymphoma (THRLBCL) is a rare histologic variant of LBCL. Limited data regarding CD19–directed chimeric antigen receptor T-cell (CART) therapy in relapsed/refractory (R/R) THRLBCL suggest poor efficacy. We investigated CART outcomes for R/R THRLBCL through the Center for International Blood and Marrow Transplant Research registry. A total of 58 adult patients with R/R THRLBCL who received commercial CD19-CART therapy between 2018 and 2022 were identified. Most patients (67%) had early relapse of disease (45% primary refractory) with a median of 3 (range, 1-7) prior therapies and were treated with axicabtagene ciloleucel (69%). At median follow-up of 23 months after CART therapy, 2-year overall and progression-free survival were 42% (95% confidence interval [CI], 27-57) and 29% (95% CI, 17-43), respectively. In univariable analysis, poor performance status before CART therapy was associated with higher mortality (hazard ratio, 2.35; 95%CI, 1.02-5.5). The 2-year cumulative incidences of relapse/progression and nonrelapse mortality were 69% and 2%, respectively. Grade ≥3 cytokine release syndrome and immune effector cell–associated neurologic syndrome occurred in 7% and 15% of patients, respectively. In this largest analysis of CD19-CART therapy for R/R THRLBCL, ∼30% of patients were alive and progression free 2 years after CART therapy. Despite a high incidence of progression (69% at 2 years), these results suggest a subset of patients with R/R THRLBCL may have durable responses with CARTs.

Scalable intracellular delivery via microfluidic vortex shedding enhances the function of chimeric antigen receptor T-cells.

Adoptive chimeric antigen receptor T-cell (CAR-T) therapy is transformative and approved for hematologic malignancies. It is also being developed for the treatment of solid tumors, autoimmune disorders, heart disease, and aging. Despite unprecedented clinical outcomes, CAR-T and other engineered cell therapies face a variety of manufacturing and safety challenges. Traditional methods, such as lentivirus transduction and electroporation, result in random integration or cause significant cellular damage, which can limit the safety and efficacy of engineered cell therapies. We present hydroporation as a gentle and effective alternative for intracellular delivery. Hydroporation resulted in 1.7- to 2-fold higher CAR-T yields compared to electroporation with superior cell viability and recovery. Hydroporated cells exhibited rapid proliferation, robust target cell lysis, and increased pro-inflammatory and regulatory cytokine secretion in addition to improved CAR-T yield by day 5 post-transfection. We demonstrate that scaled-up hydroporation can process 5 x 108 cells in less than 10 s, showcasing the platform as a viable solution for high-yield CAR-T manufacturing with the potential for improved therapeutic outcomes.

Real-world outcomes with novel therapies in relapsed/refractory diffuse large B-cell lymphoma

This study used COTA de-identified data (2010–2021) of patients in the US to explore outcomes of novel therapies in relapsed/refractory (R/R) diffuse large B-cell lymphoma (DLBCL) in real-world settings. Demographics, clinical characteristics, and clinical outcomes of patients with R/R DLBCL who received novel treatments including chimeric antigen receptor T-cell (CAR T) therapy and tafasitamab- or polatuzumab-based therapies were evaluated. Overall, 175 patients with R/R DLBCL were analyzed; 73, 69, and 27 received CAR T therapy, polatuzumab-based regimens, and tafasitamab-based regimens, respectively. In patients who had ≥1 prior lines of therapy (i.e. starting second-line or later therapy; 2 L+), CAR T, polatuzumab-based regimens, and tafasitamab-based regimens achieved a median overall survival of 26.5, 7.8, and 6.3 months, respectively. Outcomes were particularly poor for patients with relapse following CAR T, indicating that polatuzumab- and tafasitamab-based regimens in 2 L + R/R DLBCL have suboptimal outcomes in the real world. Additional treatment options are needed.

Monitoring of toxicities induced by Chimeric Antigen Receptor T-cell therapy: Protocol for a phenomenological study on the experiences of nurses

Monitoring of toxicities induced by Chimeric Antigen Receptor T-cell therapy: Protocol for a phenomenological study on the experiences of nurses

Infectious Complications Following CD30 Chimeric Antigen Receptor T-Cell Therapy in Adults.

1) The incidence of infections within the first year after CD30.CAR T-cell therapy was equivalent to that following CD19.CAR T-cell therapy2) Viral infections were more common after CD30.CAR T-cell therapy but bacterial infections predominated after CD19.CAR T-cell therapy.

Umbilical cord blood T cells can be isolated and enriched by CD62L selection for use in 'off the shelf' chimeric antigen receptor T-cell therapies to widen transplant options.

Umbilical cord blood (UCB) T cells exhibit distinct naive ontogenetic profiles and may be an attractive source of starting cells for the production of chimeric antigen receptor (CAR) T cells. Pre-selection of UCB-T cells on the basis of CD62L expression was investigated as part of a machine-based manufacturing process, incorporating lentiviral transduction, CRISPR-Cas9 editing, T-cell expansion and depletion of residual TCReeeT cells. This provided stringent mitigation against the risk of graft versus host disease (GVHD), and was combined with simultaneous knockout of CD52 to enable persistence of edited T cells in combination with preparative lymphodepletion using Alemtuzumab. Under compliant manufacturing conditions, two cell banks were generated with high levels of CAR19 expression and minimal carriage of TCReeeT cells. Sufficient cells were cryopreserved in dose-banded aliquots at the end of each campaign to treat dozens of potential recipients. Molecular characterisation captured vector integration sites and CRISPR editing signatures and functional studies, including in vivo potency studies in humanised mice, confirmed antileukaemic activity comparable to peripheral blood-derived universal CAR19 T cells. Machine manufactured UCB derived T cells banks offer an alternative to autologous cell therapies and could help widen access to CAR T cells.

Genetic and clinical characteristics of acute B-cell lymphoblastic leukemia with MEF2D fusions and report of two novel MEF2D rearrangements.

The MEF2D rearrangement is a recurrent chromosomal abnormality detected in approximately 2.4-5.3% of patients with acute B-cell lymphoblastic leukemia (B-ALL). Currently, MEF2D-rearranged B-ALL is not classified as an independent subtype in the WHO classification. Consequently, the clinical significance of MEF2D rearrangement in B-ALL remains largely unexplored. In this study, we retrospectively screened 260 B-ALL patients with RNA sequencing data collected between November 2018 and December 2022. Among these, 10 patients were identified with MEF2D rearrangements (4 with MEF2D::HNRNPUL1, 3 with MEF2D::BCL9, 1 with MEF2D::ARID1B, 1 with MEF2D::DAZAP1 and 1 with MEF2D::HNRNPM). Notably, HNRNPM and ARID1B are reported as MEF2D fusion partners for the first time. The patient with the MEF2D::HNRNPM fusion was resistant to chemotherapy and chimeric antigen receptor T-cell therapy and relapsed early after allogenic stem cell transplantation. The patient with MEF2D::ARID1B experienced early extramedullary relapse after diagnosis. All 10 patients achieved complete remission after induction chemotherapy. However, 9/10 (90%) of whom experienced relapse. Three of the 9 patients relapsed with aberrant expression of myeloid antigens. The median overall survival of these patients was only 11 months. This small cohort showed a high incidence of early relapse and short survival in patients with MEF2D rearrangements.

Chimeric antigen receptor adoptive immunotherapy in central nervous system tumors: state of the art on clinical trials, challenges, and emerging strategies to addressing them.

Central nervous system (CNS) tumors represent a significant unmet medical need due to their enduring burden of high mortality and morbidity. Chimeric antigen receptor (CAR) T-cell therapy emerges as a groundbreaking approach, offering hope for improved treatment outcomes. However, despite its successes in hematological malignancies, its efficacy in solid tumors, including CNS tumors, remains limited. Challenges such as the intricate tumor microenvironment (TME), antigenic heterogeneity, and CAR T-cell exhaustion hinder its effectiveness. This review aims to explore the current landscape of CAR T-cell therapy for CNS tumors, highlighting recent advancements and addressing challenges in achieving therapeutic efficacy. Innovative strategies aim to overcome the barriers posed by the TME and antigen diversity, prevent CAR T-cell exhaustion through engineering approaches and combination therapies with immune checkpoint inhibitors to improving treatment outcomes. Researchers have been actively working to address these challenges. Moreover, addressing the unique challenges associated with neurotoxicity in CNS tumors requires specialized management strategies. These may include the development of grading systems, monitoring devices, alternative cell platforms and incorporation of suicide genes. Continued research efforts and clinical advancements are paramount to overcoming the existing challenges and realizing the full potential of CAR T-cell therapy in treating CNS tumors.