[Clinical analysis of 18 children with aggressive mature B-cell lymphoma after liver transplantation].

Objective: To summarize the clinical characteristics, prognostic factors and treatment outcomes of childhood aggressive mature B-cell lymphoma after liver transplantation. Methods: This retrospective study included 18 children with newly diagnosed aggressive mature B-cell lymphoma after liver transplantation and treated from June 2018 to June 2022 in the Department of Hematology and Oncology of Shanghai Children's Medical Center, Shanghai Jiao Tong University School of Medicine. Clinical characteristics, treatment and outcomes of patients at last evaluation were analyzed. Overall survival (OS) and event free survival (EFS) rates were calculated by Kaplan-Meier method and Log-Rank analysis was performed to find factors of poor prognosis. Results: Among all 18 patients, there were 6 males and 12 females, and the age of onset was 40 (35, 54) months. The interval from transplant to tumor diagnosis was 21 (17, 35) months and 5 patients had early onset disease (<1 year since transplant). Seventeen patients had abdominal lesions. Diarrhea, vomiting and abdominal masses were the main clinical manifestations. All patients were Epstein-Barr virus (EBV) related posttransplant lymphoproliferative disorders (PTLD). One patient received individualized therapy due to critical sick at diagnosis, and the remaining 17 patients received CP (cyclophosphamide, methylprednisolone plus rituximab) and (or) modified EPOCH (prednisone, etoposide, doxorubicin, vincristine, cyclophosphamide plus rituximab) regimens. Of all 18 patients, 15 cases got complete response, 2 cases got partial response, 1 patient died of severe infection. The 2-year OS and EFS rates of 18 patients were (94±5)% and (83±8)%, respectively. None of age, gender or early onset disease had effect on OS and EFS rates in univariate analysis (all P>0.05). Conclusions: The symptoms of PTLD were atypical. Close surveillance of EBV-DNA for patients after liver transplantation was crucial to early stage PTLD diagnosis. CP or modified EPOCH regimen was efficient for pediatric patients with aggressive mature B cell lymphoma after liver transplantation.

Efficacy and side effects of anti-CD19 CAR T-cell therapy in patients with relapsed/refractory gastrointestinal lymphoma.

INTRODUCTION: Although anti-CD19 chimeric antigen receptor (CAR) T cell therapy was approved as a very effective salvage strategy in relapsed/refractory (R/R) B cell lymphoma, the experience in R/R gastrointestinal (GI) lymphoma is still insufficient. METHODS: We summarized the efficacy and side effects of anti-CD19 CAR T-cell therapy in 12 patients with R/R GI lymphoma. Based on literature, the R/R GI lymphoma patients were divided into subgroups with different characteristics: Bulky/No bulky disease, Gastric/Gastrointestinal involvement, Gastrointestinal/Combined extra-gastrointestinal lesions, Ulcer/Lumps or nodules type, With/without gastrointestinal bleeding. RESULTS: The objective response rate (ORR) was 66.67% in these 12 patients. The ORR was 83.33% in no bulky disease group, 80.00% in gastric involvement group, 100.00% in ulcer type group, and 80.00% in no gastrointestinal bleeding group. The CR rate was 33.33% in these 12 patients. The CR was 50.0% in no bulky disease group, 60.00% in gastric involvement group, and 80.00% in ulcer type group. The PFS and OS rate of the 12 patients at 6 months after infusion were 54.55% and 58.33%, respectively. The overall survival (OS) at 6 months was higher in no bulky disease group. There was no difference of the OS or the progression free survival (PFS) at 6 months between the other groups. The mean peak of CAR-T cells and Cytokine Release Syndrome (CRS) grade were higher in gastrointestinal lesions group. The mean peak of IFN-γ and CRS grade were higher in gastrointestinal bleeding group. Four out of six patients in group of gastrointestinal lesions group were patient with high tumor burden. Patients with gastrointestinal involvement only were at higher risk for gastrointestinal bleeding. CONCLUSIONS: The ORR and CR of high tumor load, gastrointestinal involvement, lumps or nodules type and gastrointestinal bleeding group were lower. The CRS grade was higher in gastrointestinal lesions group and in gastrointestinal bleeding group. Patients with gastrointestinal involvement only were at higher risk for gastrointestinal bleeding.

'The last bridge'- How patients experience the CAR T-cell therapy. A qualitative study.

PURPOSE: CAR T-cell therapy gives patients new hope, who are diagnosed with relapsed or refractory B-cell lymphoma or B-cell leukaemia. To date, there is no scientific knowledge about the experiences of patients with CAR T-cell therapy, their process of treatment decision making or how they handle potential side effects. The study aims at deepening the understanding of the patient's experiences, indicating how to improve nursing care for this patient population. METHOD: A qualitative study was carried out. Episodic guideline-based interviews were conducted with 14 patients who had received CAR T-cell therapy. The data analysis was performed according to the Grounded Theory. The study took place at a German university hospital. RESULTS: Data analysis showed five sequential phases including the following concepts: 'living with cancer recurrence', 'deciding on CAR T-cell therapy', 'waiting for the reinfusion of the CAR T-cells', 'experiencing CAR T-cell therapy' and 'recovering and staying healthy'. The decision for CAR T-cell therapy was characterised by the lack of alternatives and uncertainty about the outcome and side effects. CONCLUSIONS: Before, during and after CAR T-cell therapy, patients are faced with major challenges for which they need nursing support and guidance. These include preparation for CAR T-cell therapy, handling of side effects and preparation for discharge home.

Digital PCR Improves Sensitivity and Quantification in Monitoring CAR-T Cells in B Cell Lymphoma Patients.

Chimeric antigen receptor T cells (CAR-T) has emerged as a promising therapy, over 60% of patients fail to sustain a long-term response. The underlying factors that leads to the effectiveness of this therapy are not completely understood, CAR-T cell persistence and monitoring seems to be pivotal for ensuring a successful response. Various monitoring methods such as multiparametric flow cytometry (MFC) or quantitative PCR (qPCR) have been applied. Our objective is to develop digital PCR (dPCR) assays for detection and quantification of CAR-T cells, comparing them with MFC and qPCR. Samples taken at different follow-up times from 45 patients treated with CAR-T therapy were analyzed to assess the correlation between the different methodologies. dPCR presented a high correlation with MFC and qPCR (r = 0.97 and r = 0.87, respectively), while offering a higher sensitivity (0.01%) compared to MFC (0.1%) and qPCR (1%). dPCR emerged as an alternative and highly sensitivity method for monitoring CAR-T cell dynamics. This technique is well-suited for implementation in clinical practice as a complementary technique to MFC.

Ex Vivo Expanded Cord Blood Natural Killer Cells Combined with Rituximab and High-Dose Chemotherapy and Autologous Stem Cell Transplantation for B Cell Non-Hodgkin Lymphoma.

Relapse is the major cause of failure of high-dose chemotherapy (HDC) with autologous stem cell transplantation (ASCT) for B cell non-Hodgkin lymphomas (B-NHL). Improvement strategies include use in combination with effective immunotherapies. We hypothesized that the combination of rituximab/HDC/ASCT with expanded cord blood (CB)-derived natural killer (NK) cells is safe and active in B-NHL. Patients with B-NHL age 15 to 70 years and appropriate ASCT candidates were eligible for the study. The CB units were selected without considering HLA match with the recipient. The CB NK cells were expanded from day -19 to day -5. Treatment included rituximab on days -13 and -7, BEAM (carmustine/etoposide/cytarabine/melphalan) on days -13 to -7, lenalidomide on days -7 to -2, CB NK infusion (108/kg) on day -5, and ASCT (day 0). The primary endpoint was 30-day treatment-related mortality (TRM); secondary endpoints included relapse-free survival (RFS), overall survival (OS), and persistence of CB NK cells. We enrolled 20 patients. CB NK cells were expanded a median of 1552-fold with >98% purity and >96% viability. We saw no adverse events attributable to the CB NK cells and 0% 30-day TRM. At median follow-up of 47 months, the RFS and OS rates were 53% and 74%, respectively. CB NK cells were detectable in blood for 2 weeks, independent of HLA-mismatch status. CD16 expression in donor NK cells was correlated favorably with outcome, and homozygosity for the high-affinity CD16 variant (158 V/V) in CB, but not recipient, NK cells was correlated with better outcomes. Our data indicate that the combination of expanded and highly purified CB-derived NK cells with HDC/ASCT for B-NHL is safe. CD16 expression in donor NK cells, particularly if homozygous for the high-affinity CD16 variant, was correlated with better outcomes.

Differences in efficacy and safety among CAR-Ts anti-CD19/CD22, anti-CD19, and anti-CD22, in adult patients with relapse/refractory B-cell acute lymphoblastic leukemia: a meta-analysis and systematic review.

Relapsed/refractory B-cell acute lymphoblastic leukemia (R/R B-ALL) is a challenging disease with low rates of remission and survival in adult patients. Anti-CD19 Chimeric Antigen Receptor T-cells (CAR-Ts) therapies have been approved for these patients. Dual-target CAR-Ts against CD19 and CD22 have recently been developed to improve the efficacy of the single-target therapy; however, extent of the improvement using this dual-target therapy has yet to be determined. We performed a meta-analysis of the outcome and safety of CAR-Ts, comparing anti-CD19 vs anti-CD22 vs dual-target anti-CD19/CD22 CAR-Ts, to elucidate the differences and limitations of these therapies in adult patients with R/R B-ALL. Although the limitations of our study derived from heterogeneity in the included publications, our results suggest that anti-CD19/CD22 CAR-Ts generate lower incidence of relapse and neurotoxicity, but similar results were obtained regarding complete remission, minimal residual disease, overall survival, and cytokine release syndrome compared with single-target anti-CD19 and anti-CD22 CAR-Ts.

Obinutuzumab plus bendamustine for relapsed/refractory chronic lymphocytic leukemia and predictive and prognostic impact of genetic alterations: the phase II GABRIELL study.

GABRIELL was a phase II single-arm study to evaluate the efficacy and safety of obinutuzumab plus bendamustine for relapsed/refractory (R/R) chronic lymphocytic leukemia (CLL). Seventy-two patients with active disease received treatment for up to six 28-day cycles. Overall response rate was 78.6% with a median progression-free survival (PFS) of 26 months, and overall survival (OS) not reached at the end of follow-up (36 months). Undetectable measurable residual disease (≤0.01%; 36.4% in bone marrow and 53.4% in peripheral blood) correlated with a significantly longer PFS and OS (vs. >0.01). Common grade ≥3 adverse events (76.4%) were neutropenia (58.3%), thrombocytopenia (26.4%) and febrile neutropenia (11.1%). TP53 disruption was the only independent predictive factor for response (Hazard ratio; HR: 0.228). Unmutated immunoglobulin heavy chain variable region (HR: 16.061) was a negative prognostic factor for PFS. In conclusion, the combination of obinutuzumab plus bendamustine is an active and generally adequately-tolerated treatment for R/R CLL.

CAR T-Cell Persistence Correlates with Improved Outcome in Patients with B-Cell Lymphoma.

Chimeric antigen receptor (CAR) T-cell therapy has led to profound and durable tumor responses in a relevant subset of patients with relapsed/refractory (r/r) B-cell lymphomas. Still, some patients show insufficient benefit or relapse after CAR T-cell therapy. We performed a retrospective study to investigate the correlation between CAR T-cell persistence in the peripheral blood (PB) at 6 months, assessed by droplet digital PCR (ddPCR), with CAR T-cell treatment outcome. 92 patients with r/r B-cell lymphomas were treated with CD19-targeting CAR T-cell therapies at our institution between 01/2019-08/2022. Six months post-treatment, 15 (16%) patients had no detectable circulating CAR-T constructs by ddPCR. Patients with CAR T-cell persistence had a significantly higher CAR T-cell peak (5432 vs. 620 copies/ug cfDNA, p = 0.0096), as well as higher incidence of immune effector cell-associated neurotoxicity syndrome (37% vs. 7%, p = 0.0182). After a median follow-up of 8.5 months, 31 (34%) patients relapsed. Lymphoma relapses were less frequent among patients with CAR T-cell persistence (29% vs. 60%, p = 0.0336), and CAR T-cell persistence in the PB at 6 months was associated with longer progression-free survival (PFS) (HR 2.79, 95% CI: 1.09-7.11, p = 0.0319). Moreover, we observed a trend towards improved overall survival (OS) (HR 1.99, 95% CI: 0.68-5.82, p = 0.2092) for these patients. In our cohort of 92 B-cell lymphomas, CAR T-cell persistence at 6 months was associated with lower relapse rates and longer PFS. Moreover, our data confirm that 4-1BB-CAR T-cells have a longer persistence as compared to CD-28-based CAR T-cells.

Risk of a second cancer and infection in patients with indolent B-cell lymphoma exposed to first-line bendamustine plus rituximab: A retrospective analysis of an administrative claims database.

Bendamustine has a potent immunosuppressive effect because it causes T-cell lymphopenia, which might lead to a second primary malignancy (SPM) and would increase the risk of infection. Using the Medical Data Vision administrative claims database, we compared the cumulative incidence of SPM, infections within 6 months, and overall survival (OS) among untreated patients with indolent B-cell lymphomas (iBCL) who received rituximab-based chemotherapy between 2009 and 2020. Patients with grade 3b follicular lymphoma or a previous history of malignancy were excluded. Eligible 5234 patients were assigned to three cohorts: rituximab monotherapy (N = 780), RCHOP/RCVP/RTHPCOP (doxorubicin replaced with pirarubicin) (N = 2298), or bendamustine/rituximab (BR) (N = 2156). There were 589 recorded SPMs, of which myelodysplastic syndromes were the most common (1.7%). The cumulative incidence of SPM was significantly higher in patients treated with BR than in those treated with rituximab monotherapy (p < 0.01) or RCHOP/RCVP/RTHPCOP (p < 0.0001): the 5-year cumulative incidence function was 18.1%, 12.5%, and 12.9%, respectively. In the Fine-Gray subdistribution hazards model, BR showed a significantly higher cumulative incidence of SPM than RCHOP/RCVP/RTHPCOP (subhazard ratio, 1.33; 95% confidence interval [CI], 1.10-1.61). Furthermore, in sensitivity analysis, a nested case-control study using an entire cohort showed consistent results: the SPM odds ratios (95% CI) of first-line bendamustine, bendamustine after first-line, and any-line bendamustine were 1.43 (1.14-1.78), 1.26 (0.96-1.64), and 1.33 (1.09-1.62), respectively. Regarding infections, adjusted odds ratios (95% CI) of BR compared to RCHOP/RCVP/RTHPCOP were as follows: cytomegalovirus infection, 13.7 (4.88-38.4); bacterial pneumonia, 0.63 (0.50-0.78); and pneumocystis pneumonia, 0.24 (0.11-0.53). There was no significant difference in OS between RCHOP/RCVP/RTHPCOP and BR in patients with follicular, mantle cell, marginal zone, or lymphoplasmacytic lymphomas. In conclusion, treatment strategies that consider the risk of SPM and infections after chemotherapy are warranted in patients with iBCL.

Phase I Study: Safety and Efficacy of an Ex Vivo-Expanded Allogeneic Natural Killer Cell (MG4101) with Rituximab for Relapsed/Refractory B Cell Non-Hodgkin Lymphoma.

The prognosis of non-Hodgkin lymphoma (NHL) remains poor, with an unmet need for novel therapies. MG4101, an ex vivo-expanded allogeneic natural killer (NK) cell, can enhance rituximab antibody-dependent cytotoxicity in relapsed/refractory (r/r) B cell non-Hodgkin lymphoma. This study assessed the safety and efficacy of MG4101 plus rituximab for patients with r/r NHL. Patients received escalating doses of i.v. MG4101 plus rituximab every 2 weeks. IL-2 was administered s.c. after MG4101 treatment. Fludarabine plus cyclophosphamide was administered i.v. before rituximab treatment in cycles 1, 3, and 5. A 3+3 design was used to determine the maximum tolerated dose (MTD) and maximum feasible dose. Assessments were performed over a 6-cycle period, with an extended maintenance period of up to 8 cycles. Nine patients received 3 different doses of MG4101 and rituximab. MTD could not be determined because of the absence of dose-limiting toxicity. Treatment-related adverse events, mostly grade 1 or 2, occurred in 89% of patients. Only 1 patient experienced grade 1 cytokine release syndrome. MG4101 persisted for at least 7 days in 7 patients. Four patients achieved a partial response and 1 patient attained a complete response, for an overall response rate of 55.6%. Two patients showed prolonged responses and low exhaustion marker levels in T cells. For allogeneic NK cell therapy, strategies including the use of the high-affinity hFcγRIIIaV158 variant of the KIR B/x haplotype with lymphodepleting chemotherapy may be promising options for improving clinical efficacy in the antibody combination therapeutic setting as an off-the-shelf product. MG4101 plus rituximab presented a favorable safety profile and overall response rate in patients with r/r NHL.

Prognostic value of baseline and early response FDG-PET/CT in patients with refractory and relapsed aggressive B-cell lymphoma undergoing CAR-T cell therapy.

PURPOSE: Chimeric antigen receptor (CAR)-T cells are a viable treatment option for patients with relapsed or refractory (r/r) aggressive B-cell lymphomas. The prognosis of patients who relapse after CAR-T cell treatment is dismal and factors predicting outcomes need to be identified. Our aim was to assess the value of FDG-PET/CT in terms of predicting patient outcomes. METHODS: Twenty-two patients with r/r B-cell lymphoma who received CAR-T cell treatment with tisagenlecleucel (n = 17) or axicabtagene ciloleucel (n = 5) underwent quantitative FDG-PET/CT before (PET-0) and 1 month after infusion of CAR-T cells (PET-1). PET-1 was classified as complete metabolic response (CMR, Deauville score 1-3) or non-CMR (Deauville score 4-5). RESULTS: At the time of PET-1, 12/22 (55%) patients showed CMR, ten (45%) patients non-CMR. 7/12 (58%) CMR patients relapsed after a median of 223 days, three of them (25%) died. 9/10 (90%) non-CMR patients developed relapse or progressive disease after a median of 91 days, eight of them (80%) died. CMR patients demonstrated a significantly lower median total metabolic tumor volume (TMTV) in PET-0 (1 ml) than non-CMR patients (225 ml). CONCLUSION: Our results confirm the prognostic value of PET-1. 42% of all CMR patients are still in remission 1 year after CAR T-cell treatment. 90% of the non-CMR patients relapsed, indicating the need for early intervention. Higher TMTV before CAR-T cell infusion was associated with lower chances of CMR.

Infection with Neoehrlichia mikurensis promotes the development of malignant B-cell lymphomas.

The tick-borne pathogen Neoehrlichia (N.) mikurensis is implicated in persistent infection of the vascular endothelium. B cells are crucial for the host defence to this infection. Chronic stimulation of B cells may result in B-cell transformation and lymphoma. Five patients with malignant B-cell lymphoma and concomitant N. mikurensis infection were investigated regarding clinical picture, lymphoma subtype, B-cell lymphoma immunophenotype and IGHV (variable region of the immunoglobulin heavy) gene repertoire. Three of the five patients improved markedly and ceased lymphoma treatment after doxycycline treatment to eliminate N. mikurensis. Sequencing the B-cell lymphoma IGHV genes revealed preferred usage of the IGHV1 (IGHV1-2, and -69) and IGHV3 (IGHV3-15, -21, -23) families. In conclusion, N. mikurensis infection may drive the development of malignant B-cell lymphomas. Eradication of the pathogen appears to induce remission with apparent curing of the lymphoma in some cases.

Correspondence in reference to the previously published manuscript: Reduction of cycles of bendamustine plus rituximab therapy in the cases with good response for indolent B-cell lymphomas.

Takezaki et al. analyzed the outcome of 57 patients with indolent lymphomas treated with Bendamustine plus Rituximab (BR) according to the number of cycles received, showing that patients who discontinued BR after four cycles had similar outcomes compared to patients who received five or six cycles. Considering the similarities but also the differences between indolent lymphomas and chronic lymphocytic leukemia (CLL), we enriched the results obtained with a cohort of CLL patients treated with BR starting from the experience of the Lazio region group on CLL. Out of 115 patients, 97 (84%) received 4-6 cycles of BR, while 18 (16%) received 1-3 cycles. The outcome of the group of patients who received at least 4 cycles was superior in terms of response rate (ORR 96% vs. ORR 83%, p = 0.041; CR 58% vs. CR 28%, p = 0.052 respectively) and PFS [median PFS 52.6 (40.3-64.9) versus 26.2 (19.3-33.0) months, p < 0.001]. The number of patients undergoing 4 cycles of BR (4-cycles group) and 5-6 cycles (over-4-cycles group) was 9 and 88, respectively. Compared to analysis conducted by the Japanese group in indolent lymphomas, in CLL we did not observe any difference between the outcome of the 4-cycles group and the over-4-cycles group in terms of ORR (89% vs. 97%, p = 0.268) and in survival [median PFS 40.8 (13.7-67.8) versus 52.6 (38.7-66.5) months, p = 0.117]. Moreover, we observed that patients who achieved a clinical CR showed overlapping outcomes with patients who received more than 4 cycles [CR vs. non-CR median PFS not reached vs. 11.0 months; over-4-cycles group median PFS 52.6 months (40.3-64.9); p < 0.001]. Nowadays chemoimmunotherapy with BR is reserved to fit elderly CLL patients, and there are many chemo-free treatment options available; therefore, discontinuation after 4 cycles may be permissible in patients who obtained a CR in order to limit toxicity as much as possible.

A novel antibody-TCR (AbTCR) T-cell therapy is safe and effective against CD19-positive relapsed/refractory B-cell lymphoma.

PURPOSE: A barrier to widespread adoption of chimeric antigen receptor (CAR) T-cell therapy is toxicity. To address this, we recently developed a novel antibody-T-cell receptor (AbTCR) platform (trademarked as ARTEMIS®) which was designed to leverage natural immune receptor signaling and regulation. The AbTCR platform includes a gamma/delta (γδ) TCR-based AbTCR construct and a separate co-stimulatory molecule, both engineered to be tumor-specific. Here, we aim to assess the safety and preliminary efficacy of a CD19-directed AbTCR T-cell therapy. METHODS: We generated ET019003 T cells, which are autologous CD19-directed AbTCR T cells. We then conducted an early phase I study to evaluate the safety and preliminary efficacy of ET019003 T cells for the treatment of CD19-positive relapsed/refractory (r/r) B-cell lymphoma. RESULTS: Sixteen patients enrolled in this study and 12 patients were treated. Of the 12 patients treated, 6 patients (50%) achieved a complete response (CR), and 4 (33%) achieved a partial response (PR) (best objective response rate [ORR] of 83%). CRs were durable, including 2 patients with ongoing CRs for 22.7 months and 23.2 months. ET019003 was well-tolerated with an attractive safety profile. No patients experienced severe (grade ≥ 3) cytokine release syndrome (CRS) and only 1 patient experienced immune effector cell-associated neurotoxicity syndrome (ICANS) of any grade. Significant elevations of cytokine levels were not seen, even in patients with marked expansion of ET019003 T cells. CONCLUSION: This study provides initial clinical validation of the AbTCR platform as a novel cancer treatment with the potential to provide durable clinical benefit with low toxicity. TRIAL REGISTRATION: NCT03642496; Date of registration: August 22, 2018.

Efficacy and safety of universal (TCRKO) ARI-0001 CAR-T cells for the treatment of B-cell lymphoma.

Autologous T cells expressing the Chimeric Antigen Receptor (CAR) have been approved as advanced therapy medicinal products (ATMPs) against several hematological malignancies. However, the generation of patient-specific CAR-T products delays treatment and precludes standardization. Allogeneic off-the-shelf CAR-T cells are an alternative to simplify this complex and time-consuming process. Here we investigated safety and efficacy of knocking out the TCR molecule in ARI-0001 CAR-T cells, a second generation αCD19 CAR approved by the Spanish Agency of Medicines and Medical Devices (AEMPS) under the Hospital Exemption for treatment of patients older than 25 years with Relapsed/Refractory acute B cell lymphoblastic leukemia (B-ALL). We first analyzed the efficacy and safety issues that arise during disruption of the TCR gene using CRISPR/Cas9. We have shown that edition of TRAC locus in T cells using CRISPR as ribonuleorproteins allows a highly efficient TCR disruption (over 80%) without significant alterations on T cells phenotype and with an increased percentage of energetic mitochondria. However, we also found that efficient TCRKO can lead to on-target large and medium size deletions, indicating a potential safety risk of this procedure that needs monitoring. Importantly, TCR edition of ARI-0001 efficiently prevented allogeneic responses and did not detectably alter their phenotype, while maintaining a similar anti-tumor activity ex vivo and in vivo compared to unedited ARI-0001 CAR-T cells. In summary, we showed here that, although there are still some risks of genotoxicity due to genome editing, disruption of the TCR is a feasible strategy for the generation of functional allogeneic ARI-0001 CAR-T cells. We propose to further validate this protocol for the treatment of patients that do not fit the requirements for standard autologous CAR-T cells administration.

Radiation prior to chimeric antigen receptor T-cell therapy is an optimizing bridging strategy in relapsed/refractory aggressive B-cell lymphoma.

PURPOSE: We aimed to analyze the safety and efficacy of a radiation bridging regimen with or without chemotherapy compared with chemotherapy alone prior to CAR T-cell treatment for relapsed/refractory aggressive B-cell lymphoma (r/r ABL). METHODS AND MATERIALS: In this study, 45 out of 105 patients enrolled in CD19/22 CAR T-cell "cocktail" clinical trial were excluded, including 34 patients without bridging treatment. Total 60 patients receiving CAR T-cell therapies with bridging regimens as chemotherapy alone (C-CAR-T group, n = 31), and radiotherapy with or without chemotherapy (R-CAR-T group, n = 29) between February 2017 and October 2020 were retrospectively analyzed. RESULTS: No significant toxicities were identified in the R-CAR-T group, and no patients in either group experienced CAR-T-related deaths. However, the R-CAR-T group showed a lower incidence of cytokine release syndrome (CRS) of grade ≥ 3 relative to the C-CAR-T group (0% vs 19.4%, P = 0.036). The incidence of neurological toxicity was 9.9% and 6.9% in the C-CAR-T group and R-CAR-T group, respectively (P = 0.697). The R-CAR-T group achieved a higher overall response rate (ORR) at the day 30 assessment (82.8% vs 45.2%, P = 0.0025). Further analyzing the outcomes, the R-CAR-T group presented a better 1-year progression-free survival (PFS) rate than the C-CAR-T group (46.9% vs 22.6%, P = 0.0356). Intriguingly, the bridging radiation regimen extremely improved the 6-month PFS (50.8% vs 16. 7%, P = 0.0369) and 1-year overall survival (OS) (56.3% vs 33.3%, P = 0.0236) rates in patients with bulky disease. The study also found that conducting radiotherapy as a bridging regimen was an independent factor that predicted better PFS (HR: 0.534, 95% CI: 0.289-0.987, P = 0.045). CONCLUSIONS: Our results provide and strengthen novel insights that the use of radiotherapy as a bridging strategy was demonstrated to reduce the incidence of severe CRS and improve the PFS of patients. In subgroup analysis, it was confirmed that radiotherapy can improve PFS and OS in patients with bulky disease. These findings open new avenues to improve the efficacy and safety of CAR T-cell therapy.

Bhlhe40 function in activated B and TFH cells restrains the GC reaction and prevents lymphomagenesis.

The generation of high-affinity antibodies against pathogens and vaccines requires the germinal center (GC) reaction, which relies on a complex interplay between specialized effector B and CD4 T lymphocytes, the GC B cells and T follicular helper (TFH) cells. Intriguingly, several positive key regulators of the GC reaction are common for both cell types. Here, we report that the transcription factor Bhlhe40 is a crucial cell-intrinsic negative regulator affecting both the B and T cell sides of the GC reaction. In activated CD4 T cells, Bhlhe40 was required to restrain proliferation, thus limiting the number of TFH cells. In B cells, Bhlhe40 executed its function in the first days after immunization by selectively restricting the generation of the earliest GC B cells but not of early memory B cells or plasmablasts. Bhlhe40-deficient mice with progressing age succumbed to a B cell lymphoma characterized by the accumulation of monoclonal GC B-like cells and polyclonal TFH cells in various tissues.