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.

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.

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.

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.

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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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.

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.

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.

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.

Effects of sodium iodide symporter co-expression on proliferation and cytotoxic activity of chimeric antigen receptor T cells in vitro / 南方医科大学学报

OBJECTIVE@#To investigate the effects of co-expression of sodium iodide symporter (NIS) reporter gene on the proliferation and cytotoxic activity of chimeric antigen receptor (CAR)-T cells in vitro.@*METHODS@#T cells expressing CD19 CAR (CAR-T cells), NIS reporter gene (NIS-T cells), and both (NIS-CAR-T cells) were prepared by lentiviral infection. The transfection rates of NIS and CAR were determined by flow cytometry, and the cell proliferation rate was assessed using CCK-8 assay at 24, 48 and 72 h of routine cell culture. The T cells were co-cultured with Nalm6 tumor cells at the effector-target ratios of 1∶2, 1∶1, 2∶1 and 4∶1 for 24, 48 and 72 h, and the cytotoxicity of CAR-T cells to the tumor cells was evaluated using lactate dehydrogenase (LDH) assay. ELISA was used to detect the release of IFN-γ and TNF-β in the co-culture supernatant, and the function of NIS was detected with iodine uptake test.@*RESULTS@#The CAR transfection rate was 91.91% in CAR-T cells and 99.41% in NIS-CAR-T cells; the NIS transfection rate was 47.83% in NIS-T cells and 50.24% in NIS- CAR-T cells. No significant difference in the proliferation rate was observed between CAR-T and NIS-CAR-T cells cultured for 24, 48 or 72 h (P> 0.05). In the co-cultures with different effector-target ratios, the tumor cell killing rate was significantly higher in CAR-T group than in NIS-CAR-T group at 24 h (P < 0.05), but no significant difference was observed between the two groups at 48 h or 72 h (P>0.05). Higher IFN-γ and TNF-β release levels were detected in both CAR-T and NIS-CAR-T groups than in the control group (P < 0.05). NIS-T cells and NIS-CAR-T cells showed similar capacity of specific iodine uptake (P>0.05), which was significantly higher than that in the control T cells (P < 0.05).@*CONCLUSION@#The co-expression of the NIS reporter gene does not affect CAR expression, proliferation or tumor cell-killing ability of CAR-T cells.

CAR T cells redirected against tumor-specific antigen glycoforms: can low-sugar antigens guarantee a sweet success? / 医学前沿

Immune-based therapies have experienced a pronounced breakthrough in the past decades as they acquired multiple US Food and Drug Administration (FDA) approvals for various indications. To date, six chimeric antigen receptor T cell (CAR-T) therapies have been permitted for the treatment of certain patients with relapsed/refractory hematologic malignancies. However, several clinical trials of solid tumor CAR-T therapies were prematurely terminated, or they reported life-threatening treatment-related damages to healthy tissues. The simultaneous expression of target antigens by healthy organs and tumor cells is partly responsible for such toxicities. Alongside targeting tumor-specific antigens, targeting the aberrantly glycosylated glycoforms of tumor-associated antigens can also minimize the off-tumor effects of CAR-T therapies. Tn, T, and sialyl-Tn antigens have been reported to be involved in tumor progression and metastasis, and their expression results from the dysregulation of a series of glycosyltransferases and the endoplasmic reticulum protein chaperone, Cosmc. Moreover, these glycoforms have been associated with various types of cancers, including prostate, breast, colon, gastric, and lung cancers. Here, we discuss how underglycosylated antigens emerge and then detail the latest advances in the development of CAR-T-based immunotherapies that target some of such antigens.

Efficacy of Chimeric Antigen Receptor T Cell in the Treatment of Refractory/Recurrent B Acute Lymphocytic Leukemia in Children / 中国实验血液学杂志

OBJECTIVE@#To observe the efficacy of chimeric antigen receptor T cell (CAR-T) in the treatment of children with refractory/recurrent B acute lymphocytic leukemia (B-ALL).@*METHODS@#Thirty-two patients with r/r B-ALL were treated by CAR-T, the recurrence and death respectively were the end point events to evaluate the efficacy and safety of CAR-T.@*RESULTS@#The median age of the patients was 7.5 (2-17.5) years old; 40 times CAR-T were received in all patients and the median number of CAR-T was 0.9×107/kg; efficacy evaluation showed that 2 cases died before the first evaluation. Thirty patients showed that 3, 6, and 9-moth RFS was (96.3±3.6)%, (81.4±8.6)% and (65.3±12.5)%, respectively, while 3, 6, and 9-month OS was all 100%, and 12, 24-month OS was (94.7±5.1)% and (76±12.8)%. BM blasts≥36% before reinfusion and ferritin peak≥2 500 ng/ml within two weeks of CAR-T cell reinfusion were associated with recurrence. Adverse reactions mainly included cytokine release syndrome (CRS) and CART-cell-related encephalopathy syndrome (CRES), CRS appeared in 26 patients within a week of CAR-T cell reinfusion. CRES reaction was detected in 12 patients. Eighteen patients received intravenous drip of tocilizumab, among them, 12 combined with glucocorticoid. CRS and CRES reactions were relieved within one week after treatment. Hormone dosage was related to the duration of remission in patients, and the cumulative dose of methylprednisolone≥8 mg/kg showed a poor prognosis.@*CONCLUSION@#CAR-T is a safe and effective treatment for r/r B-ALL, most CRS and CRES reactions are reversible. BM blasts ≥36% before reinfusion and cumulative dose of methylprednisolone ≥8 mg/kg after reinfusion both affect the therapeutic effect. Ferritin≥2 500 ng/ml within two weeks after reinfusion is related to disease recurrence and is an independent prognostic risk factor.

Toxicity Management and Efficacy Evaluation of BCMA-CART in the Treatment of Relapsed and Refractory Multiple Myeloma / 中国实验血液学杂志

OBJECTIVE@#To investigate the toxicity management and efficacy evaluation of BCMA-chimeric antigen receptor T cells(CART) in the treatment of relapsed and refractory multiple myeloma (MM).@*METHODS@#The efficacy and adverse reactions of 21 patients with MM who received BCMA-CART treatment at the First Affiliated Hospital of Wenzhou Medical University from December 2017 to September 2020 were evaluated, and the efficacy assessment and survival analysis for high-risk patients and non-high-risk patients were evaluated.@*RESULTS@#After infusion of BCMA-CART cells in 21 MM patients, the number of effective cases was 17, of which the complete remission (sCR/CR) was 10, and the partial remission (VGPR/PR) was 7. The median OS time for all patients was 19.4 months, and the median PFS time was 7.9 months. The number of patients with extramedullary disease(EMD), high-risk genetics, and ISS stage Ⅲ were 5, 15 and 8, and the effective number was 3, 11 and 6, respectively. The treatment of 3 patients without high-risk factors was effective. The median OS and median PFS of patients with EMD were 14.2 and 2.5 months, respectively, which were shorter than those of patients without EMD (19.4 months and 8.9 months, respectively). The median OS and median PFS of patients with high-risk cytogenetic factors and ISS Ⅲ were not significantly different from those of non-high-risk patients. Cytokine release syndrane (CRS) occurred in 20 patients, of which 14 cases were Grade 1 CRS, while 6 were Grade 2, no CRS of Grade 3 or above occurred. IL-6 receptor inhibitors were used in 9 patients. All CRS were controlled effectively, and no patients had neurological toxicity.@*CONCLUSION@#BCMA-CART is a certain curative effect in the treatment of relapsed and refractory multiple myeloma, and the adverse reactions can be well controlled through close monitoring and timely treatment.

Preparation of CD52-targeted chimeric antigen receptor-modified T cells and their anti-leukemia effects / 中华血液学杂志

Objective: To construct chimeric antigen receptor (CAR) T cells targeting CD52 (CD52 CAR-T) and validate the effect of CD52 CAR-T cells on CD52-positive leukemia. Methods: A second-generation CD52-targeting CAR bearing 4-1BB costimulatory domain was ligated into a lentiviral vector through molecular cloning. Lentivirus was prepared and packaged by 293 T cells with a four-plasmid system. Fluorescein was used to label cell surface antigens to evaluate the phenotype of CD52 CAR-T cells after infection. Flow cytometry and ELISA were used to evaluate the specific cytotoxicity of CD52 CAR-T cells to CD52-positive cell lines in vitro. Results: ①A pCDH-CD52scFv-CD8α-4-1BB-CD3ζ-GFP expressing plasmid was successfully constructed and used to transduce T cells expressing a novel CD52-targeting CAR. ②On day 6, CD52-positive T cells were almost killed by CD52-targeted CAR-T post lentivirus transduction [CD52 CAR-T (4.48 ± 4.99) %, vs Vector-T (56.58±19.8) %, P=0.011]. ③T cells transduced with the CAR targeting CD52 showed low levels of apoptosis and could be expanded long-term ex vivo. ④The CD52 CAR could promote T cell differentiation into central and effector memory T cells, whereas the proportion of T cells with a CD45RA(+) effector memory phenotype were reduced. ⑤CD52 CAR-T cells could specifically kill CD52-positive HuT78-19t cells but had no killing effect on CD52-negative MOLT4-19t cells. For CD52 CAR-T cells, the percentage of residual of HuT78-19t cells was (2.66±1.60) % at an the E:T ratio of 1∶1 for 24 h, while (56.66±5.74) % of MOLT4-19t cells survived (P<0.001) . ⑥The results of a degranulation experiment confirmed that HuT78-19t cells significantly activated CD52 CAR-T cells but not MOLT4-19t cells[ (57.34±11.25) % vs (13.06± 4.23) %, P<0.001]. ⑦CD52 CAR-T cells released more cytokines when co-cultured with HuT78-19t cells than that of vector-T cells [IFN-γ: (3706±226) pg/ml, P<0.001; TNF-α: (1732±560) pg/ml, P<0.01]. Conclusions: We successfully prepared CD52 CAR-T cells with anti-leukemia effects, which might provide the foundation for further immunotherapy.

Functional investigation of chimeric antigen receptor T cells targeting LMP1 antigen / 中华血液学杂志

Objective: This study aimed to create a type of CAR-T cells that targets LMP1 antigen and study its immunotherapeutic effect on LMP1-positive hematological malignancies. Methods: To generate LMP1 CAR-T cells, a plasmid expressing LMP1 CAR was created using molecular cloning technology, and T cells were infected with LMP1 CAR lentivirus. The effects of LMP1 CAR-T cells on specific cytotoxicity against LMP1-positive tumor cell lines infected with the EB virus had been confirmed. Results: ① LMP1 protein expressing on EB virus-positive lymphoma cells surface was verified. ② The LMP1 CAR-expressing plasmid was created, and LMP1 CAR-T cells were obtained by infecting T cells with a lentivirus packaging system, with an infection efficiency of more than 80% . ③LMP1 CAR-T cells have a 4∶1 effect-to-target ratio in killing LMP1-positive lymphoma cells. The killing effect of LMP1 CAR-T cells on Raji cells was enhanced after 48 h of coculture, but there was no significant killing effect on Ramos, which are LMP1-negative lymphoma cells. ④After coculture with LMP1-positive lymphoma cells at a ratio of 1∶1 for 5 h, the degranulation effect was enhanced. The proportion of CD107a(+) T cells in the LMP1 CAR-T cell treatment group was significantly higher than that in the vector-T cell group [ (13.25±2.94) % vs (1.55±0.05) % , t=3.972, P=0.017]. ⑤After coculture with LMP1-positive lymphoma cells, the proportion of CD69(+) and CD25(+) T cells in the LMP1 CAR-T cell group was significantly higher than that in vector-T cell group [ (7.40±0.41) % vs (3.48±0.47) % , t=6.268, P=0.003; (73.00±4.73) % vs (57.67±2.60) % , t=2.842, P=0.047]. ⑥After coculture with LMP1-positive lymphoma cells, cytokine secretion in the LMP1 CAR-T cell group was higher than that in the vector-T cell group [interferon-gamma: (703±73) ng/L vs (422±87) ng/L, t=2.478, P=0.068; tumor necrosis factor-alpha: (215±35) ng/L vs (125±2) ng/L, t=2.536, P=0.064]. Conclusion: In this study, we found that the LMP1 protein is only found on the surface of the EBV-positive tumor cell. Simultaneously, we created an LMP1 CAR-expressing plasmid and obtained LMP1 CAR-T cells by infecting T cells with a lentivirus packaging system. Furthermore, we demonstrated that LMP1 CAR-T cells could specifically kill LMP1-positive tumor cells in vitro. The degranulation and activation effects of LMP1 CAR-T cells were enhanced after coculture with LMP1-positive tumor cells, indicating a potential clinical application.

Phase I study of CBM.CD19 chimeric antigen receptor T cell in the treatment of refractory diffuse large B-cell lymphoma in Chinese patients / 医学前沿

Anti-CD19 chimeric antigen receptor (CAR) T cell therapy has shown impressive efficacy in treating B-cell malignancies. A single-center phase I dose-escalation study was conducted to evaluate the safety and efficacy of T cells transduced with CBM.CD19 CAR, a second-generation anti-CD19 CAR bearing 4-1BB costimulatory molecule, for the treatment of patients with refractory diffuse large B-cell lymphoma (DLBCL). Ten heavily treated patients with refractory DLBCL were given CBM.CD19 CAR-T cell (C-CAR011) treatment. The overall response rate was 20% and 50% at 4 and 12 weeks after the infusion of C-CAR011, respectively, and the disease control rate was 60% at 12 weeks after infusion. Treatment-emergent adverse events occurred in all patients. The incidence of cytokine release syndrome in all grades and grade ⩾ 3 was 90% and 0, respectively, which is consistent with the safety profile of axicabtagene ciloleucel and tisagenlecleucel. Neurotoxicity or other dose-limiting toxicities was not observed in any dose cohort of C-CAR011 therapy. Antitumor efficacy was apparent across dose cohorts. Therefore, C-CAR011 is a safe and effective therapeutic option for Chinese patients with refractory DLBCL, and further large-scale clinical trials are warranted.

Imunoterapia com células CAR-T como nova perspectiva de tratamento da leucemia linfoblástica aguda recidivada/refratária / Immunotherapy with CAR-T cells as a new treatment perspective for relapsed/refractory acute lymphoblastic leukemia

Introdução: O tratamento da leucemia linfoblástica aguda (LLA) atualmente baseia-se em quimioterapia e/ou transplante de células tronco hematopoiéticas; entretanto, uma nova terapia vem se tornando promissora: a imunoterapia com células T modificadas geneticamente que expressam um receptor de antígeno quimérico (CAR-T) visando antígenos específicos presente em blastos de LLA, gerando resultados promissores em crianças e adultos com doença recidivada e refratária (r/r). Objetivo: Discorrer sobre a LLA e descrever a imunoterapia com CAR-T, como inovação terapêutica no tratamento da LLA de linhagem B. Método: Foi realizada uma revisão bibliográfica por meio de publicações indexadas nas bases de dados Scielo e Pubmed, utilizando os descritores: leucemia linfoblástica aguda de células B; células CAR-T; receptores de antígeno quimérico, recidivados/refratários; imunoterapia. Resultados: As altas taxas de remissão completa (42% até 100%) e parcial (28,5%) da LLA (r/r) tratadas com CAR-T, possibilitam um aumento considerável da sobrevida geral comparado a outros tratamentos convencionais. Efeitos desfavoráveis, tais como síndrome da liberação de citocinas (CRS) (0 até 90%) e neurotoxicidade (NT) (0 até 29%) podem ser vistos, sendo manejáveis, não prejudicando o desfecho do tratamento. Conclusão: A LLA é uma doença grave, de difícil tratamento e prognóstico reservado. A imunoterapia vêm se mostrando promissora à essa enfermidade, principalmente em casos de doença r/r se mostrado uma ferramenta poderosa que permite o foco específico de células malignas por meio de engenharia de células T

Introduction: The treatment of acute lymphoblastic leukemia (ALL) is currently based on chemotherapy and/or hematopoietic stem cell transplantation; however, a new therapy is becoming promising: immunotherapy with genetically modified T cells that express a chimeric antigen receptor (CAR-T) targeting specific antigens present on ALL blasts, reaching promising results in children and adults with relapsed and refractory disease (r/r). Objective: To discuss ALL and describe immunotherapy with CAR-T as a therapeutic innovation in the treatment of B-lineage ALL. Method: A literature review was carried out through publications indexed in the Scielo and Pubmed databases, using the following descriptors: B-cell acute lymphoblastic leukemia; CAR-T cells; chimeric antigen receptors, relapsed/refractory; immunotherapy. Results: The high rates of complete (42% to 100%) and partial remission (28.5%) of ALL (r/r) treated with CAR-T allows a considerable increase in overall survival compared to other conventional treatments. Unfavorable effects such as cytokine release syndrome (CRS) (0 to 90%) and neurotoxicity (NT) (0 to 29%) can be seen, being manageable, not impairing the treatment outcome. Conclusion: ALL is a serious disease, with a difficult treatment and poor prognosis. Immunotherapy has shown benefits for this disease, especially in cases of r/r ALL, showing itself to be a powerful tool that allows the specific focus of malignant cells through T cell engineering.

Analysis of Related Early Warning Indexes of Cytokine Release Syndrome in Multiple Myeloma Patients after CAR-T Treatment / 中国实验血液学杂志

OBJECTIVE@#To investigate the relationship between the levels of ferritin, C-reactive protein (CRP), lactate dehydrogenase (LDH) and interleukin-6 (IL-6) in peripheral serum and cytokine release syndrome (CRS) in patients with relapse and/or refractory multiple myeloma (R/R MM) after receiving chimeric antigen receptor T cells (CAR-T) immunotherapy.@*METHODS@#Twenty-eight patients with R/R MM were treated with 1×10@*RESULTS@#Among the 28 patients, 27 cases (96.4%) developed CRS, 24 cases (85.7%) in 1-2 grade CRS and 3 cases (10.7%) in 3-5 grade. The severity grade of CRS of 27 patients was positively correlated with the peak values of ferritin, CRP, LDH, and IL-6 in peripheral blood (r@*CONCLUSION@#After receiving CAR-T cellular immunotherapy, the incidence of CRS in patients with R/R MM is higher, but most of them are in grade 1 or 2. The severity of CRS is positively correlated with the levels of ferritin, CRP, LDH and IL-6 in peripheral blood.

CAR T-cell immunotherapy: a powerful weapon for fighting hematological B-cell malignancies / 医学前沿

The current standard of care in hematological malignancies has brought considerable clinical benefits to patients. However, important bottlenecks still limit optimal achievements following a current medical practice. The genetic complexity of the diseases and the heterogeneity of tumor clones cause difficulty in ensuring long-term efficacy of conventional treatments for most hematological disorders. Consequently, new treatment strategies are necessary to improve clinical outcomes. Chimeric antigen receptor T-cell (CAR T) immunotherapy opens a new path for targeted therapy of hematological malignancies. In this review, through a representative case study, we summarize the current experience of CAR T-cell therapy, the management of common side effects, the causative mechanisms of therapy resistance, and new strategies to improve the efficacy of CAR T-cell therapy.

Emerging immunological strategies: recent advances and future directions / 医学前沿

Immunotherapy plays a compelling role in cancer treatment and has already made remarkable progress. However, many patients receiving immune checkpoint inhibitors fail to achieve clinical benefits, and the response rates vary among tumor types. New approaches that promote anti-tumor immunity have recently been developed, such as small molecules, bispecific antibodies, chimeric antigen receptor T cell products, and cancer vaccines. Small molecule drugs include agonists and inhibitors that can reach the intracellular or extracellular targets of immune cells participating in innate or adaptive immune pathways. Bispecific antibodies, which bind two different antigens or one antigen with two different epitopes, are of great interest. Chimeric antigen receptor T cell products and cancer vaccines have also been investigated. This review explores the recent progress and challenges of different forms of immunotherapy agents and provides an insight into future immunotherapeutic strategies.