Novelty in improvement of CAR T cell-based immunotherapy with the aid of CRISPR system

Abstract Introduction Chimeric Antigen Receptor (CAR) T cells have tremendous potentials for cancer treatment; however, various challenges impede their universal use. These restrictions include the poor function of T cells in tumor microenvironments, the shortage of tumor-specific antigens and, finally, the high cost and time-consuming process, as well as the poor scalability of the method. Creative gene-editing tools have addressed each of these limitations and introduced next generation products for cell therapy. The clustered regularly interspaced short palindromic repeats-associated endonuclease 9 (CRISPR/Cas9) system has triggered a revolution in biology fields, as it has a great capacity for genetic manipulation. Method In this review, we considered the latest development of CRISPR/Cas9 methods for the chimeric antigen receptor T cell (CAR T)-based immunotherapy. Results The ability of the CRISPR/Cas9 system to generate the universal CAR T cells and also potent T cells that are persistent against exhaustion and inhibition was explored. Conclusion: We explained CRISPR delivery methods, as well as addressing safety concerns related to the use of the CRISPR/Cas9 system and their potential solutions.

Current assessment and management of measurable residual disease in patients with acute lymphoblastic leukemia in the setting of CAR-T-cell therapy / 中华医学杂志(英文版)

Chimeric antigen receptor (CAR)-modified T-cell therapy has achieved remarkable success in the treatment of acute lymphoblastic leukemia (ALL). Measurable/minimal residual disease (MRD) monitoring plays a significant role in the prognostication and management of patients undergoing CAR-T-cell therapy. Common MRD detection methods include flow cytometry (FCM), polymerase chain reaction (PCR), and next-generation sequencing (NGS), and each method has advantages and limitations. It has been well documented that MRD positivity predicts a poor prognosis and even disease relapse. Thus, how to perform prognostic evaluations, stratify risk based on MRD status, and apply MRD monitoring to guide individual therapeutic decisions have important implications in clinical practice. This review assesses the common and novel MRD assessment methods. In addition, we emphasize the critical role of MRD as a prognostic biomarker and summarize the latest studies regarding MRD-directed combination therapy with CAR-T-cell therapy and allogeneic hematopoietic stem cell transplantation (allo-HSCT), as well as other therapeutic strategies to improve treatment effect. Furthermore, this review discusses current challenges and strategies for MRD detection in the setting of disease relapse after targeted therapy.

Study on construction of c-Met specific CAR-T cells and its killing effect on non-small cell lung carcinoma / 中华肿瘤杂志

Objective: To produce chimeric antigen receptor T cells (CAR-T) targeting human hepatocyte growth factor/c-Met (HGF/c-Met) protein and detect its cytotoxicity against non-small cell lung cancer (NSCLC) cells H1975 in vitro. Methods: The whole gene sequence of c-Met CAR containing c-Met single-chain fragment variable was synthesized and linked to lentiviral vector plasmid, plasmid electrophoresis was used to detect the correctness of target gene. HEK293 cells were transfected with plasmid and the concentrated solution of the virus particles was collected. c-Met CAR lentivirus was transfected into T cells to obtain second-generation c-Met CAR-T and the expression of CAR sequences was verified by reverse transcription-quantitative real-time polymerase chain reaction (RT-qPCR) and western blot, and the positive rate and cell subtypes of c-Met CAR-T cells were detected by flow cytometry. The positive expression of c-Met protein in NSCLC cell line H1975 was verified by flow cytometry, and the negative expression of c-Met protein in ovarian cancer cell line A2780 was selected as the control. The cytotoxicity of c-Met CAR-T to H1975 was detected by lactate dehydrogenase (LDH) cytotoxicity assay at 1∶1, 5∶1, 10∶1 and 20∶1 of effector: target cell ratio (E∶T). Enzyme-linked immunosorbent assay (ELISA) was used to detect the release of cytokines such as TNF-α, IL-2 and IFN-γ from c-Met CAR-T co-cultured with H1975. Results: The size of band was consistent with that of designed c-Met CAR, suggesting that the c-Met CAR plasmid was successfully constructed. The results of gene sequencing were consistent with the original design sequence and lentivirus was successfully constructed. CAR molecules expression in T cells infected with lentivirus was detected by western blot and RT-qPCR, which showed c-Met CAR-T were successfully constructed. Flow cytometry results showed that the infection efficiency of c-Met CAR in T cells was over 38.4%, and the proportion of CD8(+) T cells was increased after lentivirus infection. The NSCLC cell line H1975 highly expressed c-Met while ovarian cancer cell line A2780 negatively expressed c-Met. LDH cytotoxicity assay indicated that the killing efficiency was positively correlated with the E∶T, and higher than that of control group, and the killing rate reached 51.12% when the E∶T was 20∶1. ELISA results showed that c-Met CAR-T cells released more IL-2, TNF-α and IFN-γ in target cell stimulation, but there was no statistical difference between c-Met CAR-T and T cells in the non-target group. Conclusions: Human NSCLC cell H1975 expresses high level of c-Met which can be used as a target for immunotherapy. CAR-T cells targeting c-Met have been successfully produced and have high killing effect on c-Met positive NSCLC cells in vitro.

Generating universal chimeric antigen receptor expressing cell products from induced pluripotent stem cells: beyond the autologous CAR-T cells / 中华医学杂志(英文版)

Adoptive therapeutic immune cells, such as chimeric antigen receptor (CAR)-T cells and natural killer cells, have established a new generation of precision medicine based on which dramatic breakthroughs have been achieved in intractable lymphoma treatments. Currently, well-explored approaches focus on autologous cells due to their low immunogenicity, but they are highly restricted by the high costs, time consumption of processing, and the insufficiency of primary cells in some patients. Induced pluripotent stem cells (iPSCs) are cell sources that can theoretically produce indefinite well-differentiated immune cells. Based on the above facts, it may be reasonable to combine the iPSC technology and the CAR design to produce a series of highly controllable and economical "live" drugs. Manufacturing hypoimmunogenic iPSCs by inactivation or over-expression at the genetic level and then arming the derived cells with CAR have emerged as a form of "off-the-shelf" strategy to eliminate tumor cells efficiently and safely in a broader range of patients. This review describes the reasonability, feasibility, superiority, and drawbacks of such approaches, summarizes the current practices and relevant research progress, and provides insights into the possible new paths for personalized cell-based therapies.

Challenges and optimal strategies of CAR T therapy for hematological malignancies / 中华医学杂志(英文版)

Remarkable improvement relative to traditional approaches in the treatment of hematological malignancies by chimeric antigen receptor (CAR) T-cell therapy has promoted sequential approvals of eight commercial CAR T products within last 5 years. Although CAR T cells' productization is now rapidly boosting their extensive clinical application in real-world patients, the limitation of their clinical efficacy and related toxicities inspire further optimization of CAR structure and substantial development of innovative trials in various scenarios. Herein, we first summarized the current status and major progress in CAR T therapy for hematological malignancies, then described crucial factors which possibly compromise the clinical efficacies of CAR T cells, such as CAR T cell exhaustion and loss of antigen, and finally, we discussed the potential optimization strategies to tackle the challenges in the field of CAR T therapy.

Progress in Chimeric Antigen Receptor-Modified Natural Killer Cells for Multiple Myeloma / 中国医学科学院学报

Although the development of novel drugs has significantly improved the survival of patients with multiple myeloma (MM) over the past decades,the lack of effective therapeutic options for relapsed and refractory MM results in poor prognosis.The chimeric antigen receptor (CAR) T-cell therapy has achieved considerable progress in relapsed and refractory MM.Nevertheless,this therapy still has limitations such as cytokine release syndrome,neurotoxicity,and off-target effects.Natural killer (NK) cells,as a critical component of the innate immune system,play an essential role in tumor immunosurveillance.Therefore,CAR-modified NK (CAR-NK) cells are put forward as a therapeutic option for MM.The available studies have suggested that multiple targets can be used as specific therapeutic targets for CAR-NK cell therapy and confirmed their antitumor effects in MM cell lines and animal models.This review summarizes the anti-tumor mechanisms,biological characteristics,and dysfunction of NK cells in the MM tumor microenvironment,as well as the basic and clinical research progress of CAR-NK cells in treating MM.

Application of TARP luciferase reporter system in function identification of CAR-T cells / 细胞与分子免疫学杂志

Objective To investigate a convenient and quantitative solution to activation levels and functional characterization of CAR-T cells by inserting T cell activity-responsive promoter (TARP) nanoluciferase reporter gene system into a lentiviral plasmid containing the gene encoding the chimeric antigen receptor (CAR). Methods The recombinant plasmid was constructed by using whole gene synthesis and molecular cloning techniques. The lentivirus was packaged and was infected with human primary T lymphocytes. Flow cytometry was used to detected the positive rate of lentivirus-infected T cells. The functional characterization of CAR-T cells was identified by luciferase reporter gene system, Western blot, flow cytometry, and small animal live imaging techniques. Results The results of enzyme digestion identification and the plasmid sequencing showed that the recombinant plasmids were constructed, and flow cytometry displayed the normal preparation of CAR-T cells. This system could dynamically respond to the activation of CAR-T cells by luciferase reporter gene system. The functional assay in vitro confirmed that the system could reflect the exhaustion of CAR-T cells, and the small animal live imaging results demonstrated that the system can be used as a tracer of CAR-T cells in mice. Conclusion TARP nanoluciferase reporter gene system provides a more convenient, sensitive and quantitative method for evaluating CAR-T cells activation level, exhaustion phenotype and tracing.

Construction of NKG2D CAR-NK92 cells and its killing effect on multiple myeloma cells / 细胞与分子免疫学杂志

Objective This study aims to construct and identify the chimeric antigen receptor NK92 (CAR-NK92) cells targeting NKG2D ligand (NKG2DL) (secreting IL-15Ra-IL-15) and verify the killing activity of NKG2D CAR-NK92 cells against multiple myeloma cells. Methods The extracellular segment of NKG2D was employed to connect 4-1BB and CD3Z, as well as IL-15Ra-IL-15 sequence to obtain a CAR expression framework. The lentivirus was packaged and transduced into NK92 cells to obtain NKG2D CAR-NK92 cells. The proliferation of NKG2D CAR-NK92 cells was detected by CCK-8 assay, IL-15Ra secretion was detected by ELISA and killing efficiency was detected by lactate dehydrogenase (LDH) assay. The molecular markers of NKp30, NKp44, NKp46, the ratio of apoptotic cell population, CD107a, and the secretion level of granzyme B and perforin were detected using flow cytometry. In addition, the cytotoxic mechanism of NKG2D CAR-NK92 cells on the tumor was verified by measuring the degranulation ability. Moreover, after NKG2D antibody inhibited effector cells and histamine inhibited tumor cells, LDH assay was utilized to detect the effect on cell-killing efficiency. Finally, the multiple myeloma tumor xenograft model was constructed to verify its anti-tumor activity in vivo. Results Lentiviral transduction significantly increased NKG2D expression in NK92 cells. Compared with NK92 cells, the proliferation ability of NKG2D CAR-NK92 cells was weaker. The early apoptotic cell population of NKG2D CAR-NK92 cells was less, and NKG2D CAR-NK92 cells had stronger cytotoxicity to multiple myeloma cells. Additionally, IL-15Ra secretion could be detected in its culture supernatant. NKp44 protein expression in NKG2D CAR-NK92 cells was clearly increased, demonstrating an enhanced activation level. Inhibition test revealed that the cytotoxicity of CAR-NK92 cells to MHC-I chain-related protein A (MICA) and MICB-positive tumor cells was more dependent on the interaction between NKG2D CAR and NKG2DL. After stimulating NKG2D CAR-NK92 cells with tumor cells, granzyme B and perforin expression increased, and NK cells obviously upregulated CD107α. Furthermore, multiple myeloma tumor xenograft model revealed that the tumors of mice treated with NKG2D CAR-NK92 cells were significantly reduced, and the cell therapy did not sensibly affect the weight of the mice. Conclusion A type of CAR-NK92 cell targeting NKG2DL (secreting IL-15Ra-IL-15) is successfully constructed, indicating the effective killing of multiple myeloid cells.

Effect of Hemoglobin on Efficacy of CAR-T Therapy in Patients with Multiple Myeloma / 中国实验血液学杂志

OBJECTIVE@#To investigate the effect of hemoglobin (Hb) on the efficacy of chimeric antigen receptor T cell therapy (CAR-T) in patients with multiple myeloma (MM).@*METHODS@#From June 2017 to December 2020, 76 MM patients who received CAR-T therapy in the Department of Hematology, The Affiliated Hospital of Xuzhou Medical University, with complete clinical data and evaluable efficacy, were selected as the research objects. According to the receiver operating characteristic (ROC) curve, the best cut-off value was obtained. The patients were divided into groups on the basis of Hb 105.5 g/L as the cut-off value. The age, sex, serum calcium, β2-microglobulin, serum creatinine, lactate dehydrogenase (LDH), and the influencing factors of CAR-T treatment efficacy in MM patients were analyzed.@*RESULTS@#Hb was an influencing factor of efficacy. Univariate analysis showed that Hb, LDH, and albumin affected the efficacy of CAR-T therapy. Multivariate analysis showed that Hb ( OR=1.039, 95% CI: 1.002-1.078) and LDH ( OR=1.014, 95% CI: 1.000-1.027) were the influencing factors for the efficacy of CAR-T therapy.@*CONCLUSION@#The efficacy of CAR-T therapy in MM patients with low Hb is poor, and Hb is a factor affecting the efficacy of CAR-T therapy.

Recent research on chimeric antigen receptor T cells in children with refractory/relapsed acute lymphoblastic leukemia / 中国当代儿科杂志

At present, the treatment of refractory/relapsed acute lymphoblastic leukemia is still in a difficult situation, and even if the intensity of chemotherapy is increased or it is combined with hematopoietic stem cell transplantation, some children may have a poor prognosis and a short survival time. Chimeric antigen receptor T-cell (CAR-T) immunotherapy uses genetically engineered T cells and does not rely on the human leukocyte antigen pathway to recognize tumor-specific antigens, and then CAR-T cells bind to target antigen cells to trigger immune response, thereby exerting a sustained anti-leukemia effect. As the most rapidly developed tumor immunotherapy, major breakthroughs have been made for CAR-T cells in the treatment of various hematological tumors, but there still lacks a comprehensive system for the research, development, and production of CAR-T cells and standardized diagnosis and treatment protocols in China. This article reviews the recent research on CAR-T cells in children with refractory/relapsed acute lymphoblastic leukemia.

Recent Progress of Nano-drug Combined with Chimeric Antigen Receptor T Cell Therapy in the Treatment of Soild Tumors / 中国肺癌杂志

Chimeric antigen receptor T cell (CAR-T) therapy has shown remarkable success in treating hematological malignancies. However, CAR-T therapy for solid tumors is still limited due to the unique solid-tumor microenvironment and heterogeneous target antigen expression, which leads to an urgent need of combining other therapies. At present, nano delivery system has become one of the most promising directions for the development of anti-tumor drugs. Based on the background of CAR-T and tumor treatment, we focus on the research progress of nanomedicine combined with CAR-T therapy, and systematically review the strategies and examples in recent years in the aspects of in vivo delivery of mRNA, regulation of tumor microenvironment, combination with photothermal therapy. And we also look forward to the future direction of this filed.
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Clinical development of chimeric antigen receptor-T cell therapy for hematological malignancies / 中华医学杂志(英文版)

Cellular therapies have revolutionized the treatment of hematological malignancies since their conception and rapid development. Chimeric antigen receptor (CAR)-T cell therapy is the most widely applied cellular therapy. Since the Food and Drug Administration approved two CD19-CAR-T products for clinical treatment of relapsed/refractory acute lymphoblastic leukemia and diffuse large B cell lymphoma in 2017, five more CAR-T cell products were subsequently approved for treating multiple myeloma or B cell malignancies. Moreover, clinical trials of CAR-T cell therapy for treating other hematological malignancies are ongoing. Both China and the United States have contributed significantly to the development of clinical trials. However, CAR-T cell therapy has many limitations such as a high relapse rate, adverse side effects, and restricted availability. Various methods are being implemented in clinical trials to address these issues, some of which have demonstrated promising breakthroughs. This review summarizes developments in CAR-T cell trials and advances in CAR-T cell therapy.

Long-term follow-up of humanized and murine CD19 CAR-T-cell therapy for B-cell acute lymphoblastic leukemia / 中华血液学杂志

Objective: Murine CD19 chimeric antigen receptor T-cell (CAR-T) products have been approved for the treatment of refractory/relapsed (R/R) B-cell acute lymphocytic leukemia (B-ALL) ; moreover, humanized products are also undergoing clinical trials. This study aimed to explore the differences in safety and short- and long-term follow-up efficacy between humanized and murine CD19 CAR-T-cells for treating relapsed and refractory B-ALL. Methods: Clinical data of 80 patients with R/R B-ALL treated with CD19-targeted CAR-T-cells at the Union Hospital of Tongji Medical College of Huazhong University of Science and Technology between May 2016 and March 2023 were analyzed, which included 31 patients with murine CAR-T and 49 with humanized products. Results: The proportion of patients with cytokine-release syndrome (CRS) in the murine and humanized groups was 63.1% and 65.3%, respectively. Moreover, a higher proportion of patients suffered from severe CRS in the murine group than in the humanized CAR-T group (19.4% vs 8.2%, P=0.174). Furthermore, one patient per group died of grade 5 CRS. The incidence of grade 1-2 immune effector cell-associated neurotoxicity syndrome (ICANS) was 12.9% and 6.1%, respectively; severe ICANS were not observed. Among patients receiving murine CAR-T-cells, an overall response (OR) was observed in 74.2%. Conversely, the OR rate of patients receiving humanized CAR-T-cells was 87.8%. During the median follow-up time of 10.5 months, the median recurrence-free survival (RFS) of patients with murine CAR-T-cells was 12 months, which was as long as that of patients with humanized CAR-T-cells. The median overall survival (OS) were not reached in both groups. Of the 45 patients with a bone marrow burden over 20% at baseline, humanized CAR-T therapy was associated with a significantly improved RFS (43.25% vs 33.33%, P=0.027). Bridging transplantation was an independent factor in prolonging OS (χ(2)=8.017, P=0.005) and PFS (χ(2)=6.584, P=0.010). Common risk factors, such as age, high proportion of bone marrow blasts, and BCR-ABL fusion gene expression, had no significant effect on patients' long-term follow-up outcomes. Three patients reached complete remission after reinfusion of humanized CAR-T-cells. However, one patient relapsed one month after his second infusion of murine CAR-T-cells. Conclusions: The results indicate that humanized CAR-T therapy showed durable efficacy in patients with a higher tumor burden in the bone marrow without any influence on safety. Moreover, it could overcome immunogenicity-induced CAR-T resistance, providing treatment options for patients who were not treated successfully with CAR-T therapies.

Clinical analysis of long-term survival and influencing factors of chimeric antigen receptor T-cell therapy in relapsed/refractory acute B-cell lymphoblastic leukemia / 中华血液学杂志

Objective: To analyze the survival and influencing factors of chimeric antigen receptor (CAR) T-cell therapy in relapsed/refractory acute B-cell lymphoblastic leukemia (R/R B-ALL) . Methods: Clinical information of patients who received CAR-T-cell therapy and achieved complete remission of R/R B-ALL between May 2015 and June 2018 at the Shaanxi Provincial People's Hospital was obtained. Kaplan-Meier analysis was used to evaluate the overall survival (OS) and leukemia-free survival (LFS) times of patients, and Cox regression analysis was performed to analyze the prognostic factors that affect patient survival after CAR-T therapy. Results: Among the 38 patients with R/R B-ALL, 21 were men, with a median age of 25 (6-59) years and a median OS time of 18 (95% CI 3-33) months. Multivariate Cox regression analysis showed that positive MLL-AF4 fusion gene expression was an independent risk factor for OS and LFS (OS: HR=4.888, 95% CI 1.375-17.374, P=0.014; LFS: HR=6.683, 95% CI 1.815-24.608, P=0.004). Maintenance therapy was a protective factor for OS and LFS (OS: HR=0.153, 95% CI 0.054-0.432, P<0.001; LFS: HR=0.138, 95% CI 0.050-0.382, P<0.001). In patients with MRD negative conversion, LFS benefit (HR=0.209, 95% CI 0.055-0.797, P=0.022) and OS difference was statistically insignificant (P=0.111). Moreover, patients with high tumor burden were risk factors for OS and LFS at the level of 0.1 (OS: HR=2.662, 95% CI 0.987-7.184, P=0.053; LFS: HR=2.452, 95% CI 0.949-6.339, P=0.064) . Conclusion: High tumor burden and high-risk genetics may affect the long-term survival rate of patients with R/R B-ALL receiving CAR-T, and lenalidomide-based maintenance therapy may improve their prognosis.

Analysis of the feasibility and prognostic value of circulating tumor DNA monitoring in detecting gene mutations in patients with diffuse large B-cell lymphoma receiving chimeric antigen receptor T-cell therapy / 中华血液学杂志

Objective: To explore the prognostic value of circulating tumor DNA (ctDNA) testing in patients with refractory/relapsed diffuse large B-cell lymphoma (R/R DLBCL) undergoing chimeric antigen receptor T-cell (CAR-T) therapy, and to guide the prevention and subsequent treatment of CAR-T-cell therapy failure. Methods: In this study, 48 patients with R/R DLBCL who received CAR-T-cell therapy at the First Affiliated Hospital of Zhejiang University School of Medicine between December 2017 and March 2022 were included. Furthermore, ctDNA testing of 187 lymphoma-related gene sets was performed on peripheral blood samples obtained before treatment. The patients were divided into complete remission and noncomplete remission groups. The chi-square test and t-test were used to compare group differences, and the Log-rank test was used to compare the differences in survival. Results: Among the patients who did not achieve complete remission after CAR-T-cell therapy for R/R DLBCL, the top ten genes with the highest mutation frequencies were TP53 (41%), TTN (36%), BCR (27%), KMT2D (27%), IGLL5 (23%), KMT2C (23%), MYD88 (23%), BTG2 (18%), MUC16 (18%), and SGK1 (18%). Kaplan-Meier survival analysis revealed that patients with ctDNA mutation genes >10 had poorer overall survival (OS) rate (1-year OS rate: 0 vs 73.8%, P<0.001) and progression-free survival (PFS) rate (1-year PFS rate: 0 vs 51.8%, P=0.011) compared with patients with ctDNA mutation genes ≤10. Moreover, patients with MUC16 mutation positivity before treatment had better OS (2-year OS rate: 56.8% vs 26.7%, P=0.046), whereas patients with BTG2 mutation positivity had poorer OS (1-year OS rate: 0 vs 72.5%, P=0.005) . Conclusion: ctDNA detection can serve as a tool for evaluating the efficacy of CAR-T-cell therapy in patients with R/R DLBCL. The pretreatment gene mutation burden, mutations in MUC16 and BTG2 have potential prognostic value.

Efficacy and safety analysis of the zanubrutinib-based bridging regimen in chimeric antigen receptor T-cell therapy for relapsed/refractory diffuse large B-cell lymphoma / 中华血液学杂志

Objective: To further elucidate the clinical efficacy and safety of a combination regimen based on the BTK inhibitor zebutanil bridging CD19 Chimeric antigen receptor T cells (CAR-T cells) in the treatment of relapsed/refractory diffuse large B-cell lymphoma (r/r DLBCL) . Methods: Twenty-one patients with high-risk r/r DLBCL were treated with a zanubrutinib-based regimen bridging CAR-T between June 2020 and June 2023 at the Department of Hematology, Tongji Hospital, Tongji University and the Second Affiliated Hospital of Zhejiang University, and the efficacy and safety were retrospectively analyzed. Results: All 21 patients were enrolled, and the median age was 57 years (range: 38-76). Fourteen patients (66.7%) had an eastern cooperative oncology group performance status score (ECOG score) of ≥2. Eighteen patients (85.7%) had an international prognostic index (IPI) score of ≥3. Three patients (14.3%) had an IPI score of 2 but had extranodal infiltration. Fourteen patients (66.7%) had double-expression of DLBCL and seven (33.3%) had TP53 mutations. With a median follow-up of 24.8 (95% CI 17.0-31.6) months, the objective response rate was 81.0%, and 11 patients (52.4%) achieved complete remission. The median progression-free survival (PFS) was 12.8 months, and the median overall survival (OS) was not reached. The 1-year PFS rate was 52.4% (95% CI 29.8% -74.3%), and the 1-year OS rate was 80.1% (95% CI 58.1% -94.6%). Moreover, 18 patients (85.7%) had grade 1-2 cytokine-release syndrome, and two patients (9.5%) had grade 1 immune effector cell-associated neurotoxicity syndrome. Conclusion: Zanubrutinib-based combination bridging regimen of CAR-T therapy for r/r DLBCL has high efficacy and demonstrated a good safety profile.

Efficacy and safety of fourth-generation CD19 CAR-T expressing IL7 and CCL19 along with PD-1 monoclonal antibody for relapsed or refractory large B-cell lymphoma / 中华血液学杂志

Objective: This study systematically explore the efficacy and safety of fourth-generation chimeric antigen receptor T-cells (CAR-T), which express interleukin 7 (IL7) and chemokine C-C motif ligand 19 (CCL19) and target CD19, in relapsed or refractory large B-cell lymphoma. Methods: Our center applied autologous 7×19 CAR-T combined with tirelizumab to treat 11 patients with relapsed or refractory large B-cell lymphoma. The efficacy and adverse effects were explored. Results: All 11 enrolled patients completed autologous 7×19 CAR-T preparation and infusion. Nine patients completed the scheduled six sessions of tirolizumab treatment, one completed four sessions, and one completed one session. Furthermore, five cases (45.5%) achieved complete remission, and three cases (27.3%) achieved partial remission with an objective remission rate of 72.7%. Two cases were evaluated for disease progression, and one died two months after reinfusion because of uncontrollable disease. The median follow-up time was 31 (2-34) months, with a median overall survival not achieved and a median progression-free survival of 28 (1-34) months. Two patients with partial remission achieved complete remission at the 9th and 12th months of follow-up. Therefore, the best complete remission rate was 63.6%. Cytokine-release syndrome and immune effector cell-associated neurotoxicity syndrome were controllable, and no immune-related adverse reactions occurred. Conclusion: Autologous 7×19 CAR-T combined with tirelizumab for treating relapsed or refractory large B-cell lymphoma achieved good efficacy with controllable adverse reactions.

Characteristics and impact factors of SARS-CoV-2 infection in adult patients with relapsed/refractory B-cell non-Hodgkin lymphoma receiving chimeric antigen receptor T-cell therapy / 中华血液学杂志

Objective: To explore the clinical characteristics and treatment of COVID-19 infection in patients with relapsed/refractory B-cell non-Hodgkin lymphoma before and after receiving chimeric antigen receptor T-cell therapy, and study the influencing factors of severe COVID-19 infection in these patients. Methods: The data of 59 patients with relapsed/refractory B-cell non-Hodgkin lymphoma who received chimeric antigen receptor T-cell therapy at the Department of Hematology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology and Department of Hematology, the Second Affiliated Hospital, College of Medicine, Zhejiang University between December 2017 and February 2023, and who were infected with novel coronavirus between December 2022 and February 2023 were retrospectively studied. Patients were divided into light, medium, severe, and critical groups, and the differences between the groups were analyzed using the chi-square test. A univariate logistic regression model was used to evaluate the contribution of each variable and its relationship with severe infection. The chi-square and Fisher's exact tests were used to analyze the differences between the B-cell aplasia and B-cell recovery (BCR) groups. Results: Of the 59 pre- and post-infusion infections, 39 (66.1%) led to mild COVID-19, 9 (15.3%) resulted in moderate COVID-19, 10 (16.9%) resulted in severe COVID-19, and 1 (1.7%) led to critical COVID-19. Moroever, age greater than 55 years, having received autologous hematopoietic stem cell transplantation, progressive disease status, and B-cell aplasia at the time of diagnosis of COVID-19 infection are factors affecting severe infection. Patients with B-cell aplasia had a more severe infection with COVID-19 (P<0.001), a longer duration (P=0.015), a longer antiviral therapy course (P<0.001), and a higher hospitalization rate (P<0.001) than the BCR group. Conclusion: Active prevention and treatment of COVID-19 infection remains a crucial issue requiring urgent attention in managing patients with relapsed/refractory B-cell non-Hodgkin lymphoma treated with chimeric antigen receptor T-cell therapy.

Alteration and significance of serum lipid levels and nutritional status during BCMA-CAR-T-cell therapy in patients with refractory or relapsed multiple myeloma: a retrospective study based on LEGEND-2 / 中华血液学杂志

Objective: To explore the dynamic changes in serum lipid levels and nutritional status during BCMA-CAR-T-cell therapy in patients with refractory or relapsed multiple myeloma (R/R MM) based on LEGEND-2. Methods: The data of patients with R/R MM who underwent BCMA-CAR-T therapy at our hospital between March 30, 2016, and February 6, 2018, were retrospectively collected. Serum lipid levels, controlled nutritional status (CONUT) score, and other clinical indicators at different time points before and after CAR-T-cell infusion were compared and analyzed. The best cut-off value was determined by using the receiver operator characteristic (ROC) curve. The patients were divided into high-CONUT score (>6.5 points, malnutrition group) and low-CONUT score groups (≤6.5 points, good nutrition group), comparing the progression-free survival (PFS) and total survival (OS) of the two groups using Kaplan-Meier survival analysis. Results: Before the infusion of CAR-T-cells, excluding triglycerides (TG), patients' serum lipid levels were lower than normal on average. At 8-14 d after CAR-T-cell infusion, serum albumin (ALB), total cholesterol (TC), high-density lipoprotein (HDL), low-density lipoprotein (LDL), and apolipoprotein A1 (Apo A1) levels dropped to the minimum, whereas CONUT scores reached the maximum. In addition to TG, apolipoprotein B (Apo B) levels increased compared with baseline. After CAR-T-cell therapy, the patients' serum lipid levels significantly increased with well-improved nutritional status. Spearman's related analysis showed that TC, HDL, and ApoA1 levels after CAR-T-cell injection were significantly negatively correlated with the grade of cytokine-release syndrome (CRS) (r=-0.548, P=0.003; r=-0.444, P=0.020; r=-0.589, P=0.001). Furthermore, survival analysis indicated that the CONUT score was unrelated to PFS, and the median OS of patients with R/R MM in the high-CONUT score group was shorter than that in the low-CONUT score group (P=0.046) . Conclusions: During CAR-T-cell therapy, hypolipidemia and poor nutritional status were aggravated, which is possibly related to CRS. The patients' serum lipid levels and nutritional status were significantly improved after CAR-T-cell treatment. The CONUT score affected the median OS in patients treated with CAR-T-cells. Therefore, specific screening and intervention for nutritional status in patients receiving CAR-T-cell therapy are required.

Treatment response of a two-dose regimen of dose-adjusted inotuzumab ozogamicin in relapsed/refractory B-cell acute lymphoblastic leukemia / 中华血液学杂志

Objective: To observe the treatment response of a two-dose regimen of inotuzumab ozogamicin (inotuzumab), a monoclonal antibody targeting CD22, for patients with heavily treated relapsed/refractory B-cell acute lymphoblastic leukemia (R/R B-ALL), including those failed or relapsed after chimeric antigen receptor (CAR) -T-cell therapy. Methods: Pediatric and adult patients who received two doses of inotuzumab and who were evaluated after inotuzumab treatment were included. Antibody infusions were performed between March 2020 and September 2022. All patients expressed CD22 antigen as detected by flow cytometry (>80% leukemic cells displaying CD22) before treatment. For adults, the maximum dosage per administration was 1 mg (with a total of two administrations). For children, the maximum dosage per administration was 0.85 mg/m(2) (no more than 1 mg/dose; total of two administrations). The total dosage administered to each patient was less than the standard dosage of 1.8 mg/m(2). Results: Twenty-one patients with R/R B-ALL were included, including five children (<18 years old) and sixteen adults. Seventeen patients presented with 5.0% -99.0% leukemic blasts in the bone marrow/peripheral blood or with extramedullary disease, and four patients were minimal residual disease (MRD) -positive. Fourteen patients underwent both CD19 and CD22 CAR-T-cell therapy, four underwent CD19 CAR-T-cell therapy, and three underwent blinatumomab therapy. Eleven patients underwent allogeneic hematopoietic stem cell transplantation (allo-HSCT). After inotuzumab treatment, 14 of 21 patients (66.7% ) achieved a complete response (CR, one was MRD-positive CR), and all four MRD-positive patients turned MRD-negative. Four of six patients who failed recent CD22 CAR-T-cell therapy achieved a CR after subsequent inotuzumab treatment. Seven patients (33.3% ) demonstrated no response. Grade 1-3 hepatotoxicity occurred in five patients (23.8% ), one child with no response experienced hepatic veno-occlusive disease (HVOD) during salvage transplantation and recovered completely. Conclusion: For patients with heavily treated R/R B-ALL, including those who had undergone allo-HSCT and CD19/CD22 CAR-T-cell therapy, the two-dose regimen of inotuzumab resulted in a CR rate of 66.7%, and the frequency of hepatotoxicity and HVOD was low.