2022 Chinese expert consensus and guidelines on clinical management of toxicity in anti-CD19 chimeric antigen receptor T-cell therapy for B-cell non-Hodgkin lymphoma

Adoptive cellular immunotherapy with chimeric antigen receptor(CAR)T cells has emerged as a novel modality for treating relapsed and/or refractory B-cell non-Hodgkin lymphoma(B-NHL).With increasing approval of CAR T-cell products and advances in CAR T cell therapy,CAR T cells are expected to be used in a growing number of cases.However,CAR T-cell-associated toxicities can be severe or even fatal,thus compromising the survival benefit from this therapy.Standardizing and studying the clinical management of these toxicities are imperative.In contrast to other hematological malignancies,such as acute lymphoblastic leukemia and multiple myeloma,anti-CD19 CAR T-cell-associated toxicities in B-NHL have several distinctive features,most notably local cytokine-release syndrome(CRS).However,previously published guidelines have provided few specific recommendations for the grading and management of toxicities associated with CAR T-cell treatment for B-NHL.Consequently,we developed this consensus for the prevention,recognition,and management of these toxicities,on the basis of published literature regarding the management of anti-CD19 CAR T-cell-associated toxicities and the clinical experience of multiple Chinese institutions.This consensus refines a grading system and classification of CRS in B-NHL and corresponding measures for CRS management,and delineates comprehensive principles and exploratory recommendations for managing anti-CD19 CAR T-cell-associated toxicities in addition to CRS.

Reciprocal activation of antigen-presenting cells and CAR T cells triggers a widespread endogenous anti-tumor immune response through sustained high-level IFNγproduction

Adoptive cell transfer(ACT)using chimeric antigen receptor(CAR)modified T cells and T cell receptor(TCR)engineered T cells has shown therapeutic efficacy in cancer treatment1,2.CAR T cells are widely applicable to tumor patients because of their ability to directly identify tumor cells in an MHCindependent manner.

Cytokine-induced killer (ClK) cells:from basic research to clinical translation

The accumulation of basic researches and clinical studies related to cytokine-induced killer(CIK) cells has confirmed their safety and feasibility in treating malignant diseases.This review summarizes the available published literature related to the biological characteristics and clinical applications of CIK cells in recent years.A number of clinical trials with CIK cells have been implemented during the progressive phases of cancer,presenting potential widespread applications of CIK cells for the future.Furthermore,this review briefly compares clinical applications of CIK cells with those of other adoptive immunotherapeutic cells.However,at present,there are no uniform criteria or large-scale preparations of CIK cells.The overall clinical response is difficult to evaluate because of the use of autologous CIK cells.Based on these observations,several suggestions regarding uniform criteria and universal sources for CIK cell preparations and the use of CIK cells either combined with chemotherapy or alone as a primary strategy are briefly proposed in this review.Large-scale,controlled,grouped,and multi-center clinical trials on CIK cell-based immunotherapy should be conducted under strict supervision.These interventions might help to improve future clinical applications and increase the clinical curative effects of CIK cells for a broad range of malignancies in the future.

Inducing immunogenic cell death in immuno-oncological therapies

Immunotherapy has revolutionized cancer treatment and substantially improved patient outcomes with respect to multiple types of tumors.However,most patients cannot benefit from such therapies,mainly due to the intrinsic low immunogenicity of cancer cells(CCs)that allows them to escape recognition by immune cells of the body.Immunogenic cell death(ICD),which is a form of regulated cell death,engages in a complex dialogue between dying CCs and immune cells in the tumor microenvironment(TME),ultimately evoking the damage-associated molecular pattern(DAMP)signals to activate tumor-specific immunity.The ICD inducers mediate the death of CCs and improve both antigenicity and adjuvanticity.At the same time,they reprogram TME with a“cold-warmhot”immune status,ultimately amplifying and sustaining dendritic cell-and T cell-dependent innate sensing as well as the antitumor immune responses.In this review,we discuss how to stimulate ICD based upon the biological properties of CCs that have evolved under diverse stress conditions.Additionally,we highlight how this dynamic interaction contributes to priming tumor immunogenicity,thereby boosting anticancer immune responses.We believe that a deep understanding of these ICD processes will provide a framework for evaluating its vital role in cancer immunotherapy.

New two chamber transfer switch for 6500 A commutation current

HVDC transfer switches are used in different locations in electrode lines of HVDC transmission systems for their reconfigurations. They have to carry and commutate currents to the overload currents of HVDC transmission systems, which increased to 6,400 A in the past years. Common designs of transfer switches use combinations of several switching units connected in series and parallel. This paper describes the design and development of a new DC commutation switch with two switching units only, but it is able to carry currents up to 10,000 A and has an actual tested commutation capability of 6,500 A.

Programming CAR T cells to enhance anti-tumor efficacy through remodeling of the immune system

Chimeric antigen receptor(CAR)T cells have been indicated effective in treating B cell acute lymphoblastic leukemia and non-Hodgkin lymphoma and have shown encouraging results in preclinical and clinical studies.However,CAR T cells have achieved minimal success against solid malignancies because of the additional obstacles of their insufficient migration into tumors and poor amplification and persistence,in addition to antigen-negative relapse and an immunosuppressive microenvironment.Various preclinical studies are exploring strategies to overcome the above challenges.Mobilization of endogenous immune cells is also necessary for CAR T cells to obtain their optimal therapeutic effect given the importance of the innate immune responses in the elimination of malignant tumors.In this review,we focus on the recent advances in the engineering of CAR T cell therapies to restore the immune response in solid malignancies,especially with CAR T cells acting as cellular carriers to deliver immunomodulators to tumors to mobilize the endogenous immune response.We also explored the sensitizing effects of conventional treatment approaches,such as chemotherapy and radiotherapy,on CAR T cell therapy.Finally,we discuss the combination of CAR T cells with biomaterials or oncolytic viruses to enhance the anti-tumor outcomes of CAR T cell therapies in solid tumors.

Tumor-suppressive function and mechanism of HOXB13 in right-sided colon cancer

Right-sided colon cancer(RCC)and left-sided colon cancer(LCC)differ in their clinical and molecular features.An investigation of differentially expressed genes(DEGs)between RCC and LCC could contribute to targeted therapy for colon cancer,especially RCC,which has a poor prognosis.Here,we identified HOXB13,which was significantly less expressed in RCC than in LCC and associated with prognosis in RCC,by using 5 datasets from the Gene Expression Omnibus(GEO).Tissue sample analysis showed that HOXB13 was differentially expressed between normal and only RCC tumor tissues.HOXB13 inhibited colon cancer cell proliferation and induced apoptosis both in vitro and in vivo.Furthermore,we found that HOXB13 might be regulated by DNMT3B and suppress C-myc expression to exert antitumor effects viaβ-catenin/TCF4 signals in RCC.In conclusion,the current study is the first to demonstrate that HOXB13 has a tumor-suppressive effect in RCC.High expression levels of HOXB13 are associated with prolonged overall survival in patients with RCC.The DNMT3B-HOXB13-C-myc signaling axis might be a molecular target for the treatment of RCC.

Challenges and optimal strategies of CAR T therapy for hematological malignancies

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.

Characteristics of premanufacture CD8^(+) T cells determine CAR-T efficacy in patients with diffuse large B-cell lymphoma

Although chimeric antigen receptor(CAR)T cells have become an important treatment option for patients with relapsed/refractory B-cell malignancies,more than 60%of patients with diffuse large B-cell lymphoma(DLBCL)treated with CAR-T cell therapies fail to achieve a durable response.To reveal changes in CAR-T cell therapy and identify response biomarkers,we conducted a retrospective analysis of pre-manufacture source T cells and CAR-T cell products and their association with outcome in 58 patients with r/rDLBCL who received tandem CD19/CD20 CAR-T cell therapy.We performed bulk RNA-Seq,single-cell RNA-Seq,and paired T cell receptor sequencing on CAR-T cell products and pre-manufacture T cells from DLBCL patients.We note that a CD8+stem cell-like memory T cell population with a higher proportion and enhanced activating capacity of the CAR-T cell products was key to achieving durable clinical response.By analysing autologously-derived,pre-manufacture T cells,our data suggest that heterogeneity in the cellular and molecular features of pre-manufacture T cells contribute to the variation in efficacy after CAR-T cell therapy in DLBCL.The differences in anti-tumour efficacy of CAR-T cells among patients with different clinical outcomes appear to be due to the loss of CCR7 gene expression,coupled with increased expression of activation-and inhibitor-related genes in the CD8+naïve-T cell populations among the apheresis T cells from patients with a poor molecular response.These findings significantly advance our understanding of the underlying molecular determinants of pre-manufacture T cell function.

Optimized collaboration of the first and third signals endows robust activity to T cells within the immunocompetent tumor microenvironment

CAR T-cell therapy has shown remarkable potential in the treatment of hematologic malignancies,and these successes have greatly motivated research on treatment of solid tumors.Although numerous clinical trials have been actively carried out,exciting clinical responses are still sporadic and may be are transient for patients with solid tumors[1].

Chimeric antigen receptor-modified T cells for the immunotherapy of patients with EGFR-expressing advanced relapsed/refractory non-small cell lung cancer

The successes achieved by chimeric antigen receptor-modified T （CAR-T） cells in hematological malignancies raised the pos- sibility of their use in non-small lung cancer （NSCLC）. In this phase I clinical study （NCT01869166）, patients with epidermal growth factor receptor （EGFR）-positive （〉50% expression）, relapsed/refractory NSCLC received escalating doses of EGFR-targeted CAR-T cell infusions. The EGFR-targeted CAR-T cells were generated from peripheral blood after a 10 to 13-day in vitro expansion. Serum cytokines in peripheral blood and copy numbers of CAR-EGFR transgene in peripheral blood and in tissue biopsy were monitored periodically. Clinical responses were evaluated with RECISTI.1 and im- mune-related response criteria, and adverse events were graded with CTCAE 4.0. The EGFR-targeted CAR-T cell infusions were well-tolerated without severe toxicity. Of 11 evaluable patients, two patients obtained partial response and five had stable disease for two to eight months. The median dose of transfused CAR＋ T cells was 0.97x 10^7 cells kg J （interquar- tile range （IQR）, 0.45 to 1.09x 10^7 cells kg 1）. Pathological eradication of EGFR positive tumor cells after EGFR-targeted CAR-T cell treatment can be observed in tumor biopsies, along with the CAR-EGFR gene detected in tumor-infiltrating T cells in all four biopsied patients. The EGFR-targeted CAR-T cell therapy is safe and feasible for EGFR-positive advanced re- lapsed/refractory NSCLC.

Mesenchymal stem cells-derived exosomal microRNAs contribute to wound inflammation

Clinical and experimental studies have highlighted the significance of inflammation in coordinating wound repair and regeneration.However,it remains challenging to control the inflammatory response and tolerance at systemic levels without causing toxicity to injured tissues.Mesenchymal stem cells(MSCs) possess potent immunomodulatory properties and facilitate tissue repair by releasing exosomes,which generate a suitable microenvironment for inflammatory resolution.Exosomes contain several effective bioactive molecules and act as a cell-cell communication vehicle to influence cellular activities in recipient cells.During this process,the horizontal transfer of exosomal microRNAs(miRNAs) to acceptor cells,where they regulate target gene expression,is of particular interest for understanding the basic biology of inflammation ablation,tissue homeostasis,and development of therapeutic approaches.In this review,we describe a signature of three specific miRNAs(miR-21,miR-146 a,and miR-181) present in human umbilical cord MSC-derived exosomes(MSC-EXO) identified microarray chip analysis and focus on the inflammatory regulatory functions of these immune-related miRNAs.We also discuss the potential mechanisms contributing to the resolution of wound inflammation and tissue healing.

Current status and perspectives of chimeric antigen receptor modified T cells for cancer treatment

Chimeric antigen receptor （CAR） is a recombinant immunoreceptor combining an antibody-derived target- ing fragment with signaling domains capable of acti- vating cells, which endows T cells with the ability to recognize tumor-associated surface antigens indepen- dent of the expression of major histocompatibiiity complex （MHC） molecules. Recent early-phase clinical trials of CAR-modified T （CAR-T） cells for relapsed or refractory B cell malignancies have demonstrated promising results （that is, anti-CD19 CAR-T in B cell acute lymphoblastic leukemia （B-ALL））. Given this suc- cess, broadening the clinical experience of CAR-T cell therapy beyond hematological malignancies has been actively investigated. Here we discuss the basic design of CAR and review the clinical results from the studies of CAR-T cells in B cell leukemia and lymphoma, and several solid tumors. We additionally discuss the major challenges in the further development and strategies for increasing anti-tumor activity and safety, as well as for successful commercial translation.

Effective and persistent antitumor activity of HER2-directed CAR-T cells against gastric cancer cells in vitro and xenotransplanted tumors in vivo

Human epidermal growth factor receptor 2 （HER2） pro- teins are overexpressed in a high proportion of gastric cancer （GC） cases and affect the maintenance of cancer stem cell （CSC） subpopulations, which are used as tar- gets for the clinical treatment of patients with HER2- positive GC. Despite improvements in survival, numer- ous HER2-positive patients fail treatment with trastuzu- mab, highlighting the need for more effective therapies. In this study, we generated a novel type of genetically modified human T cells, expressing a chimeric antigen receptor （CAR）, and targeting the GC cell antigen HER2, which harbors the CD137 and CD3/; moieties. Our findings show that the expanded CART cells, expressing an increased central memory phenotype, were activated by the specific recognition of HER2 antigens in an MHC-in- dependent manner, and effectively killed patient-derived HER2-positive GC cells. In HER2-positive xenograft tumors, CART cells exhibited considerably enhanced tumor inhibition ability, long-term survival, and homing totargets, compared with those of non-transduced T cells. The sphere-forming ability and in vivo tumorigenicity of patient-derived gastric cancer stem-like cells, expressing HER2 and the CD44 protein, were also inhibited. Our results support the future development and clinical application of this adoptive immunotherapy in patients with HER2-positive advanced GC.

Genetic engineering of T cells with chimeric antigen receptors for hematological malignancy immunotherapy

The host immune system plays an instrumental role in the surveillance and elimination of tumors by recognizing and destroying cancer cells. In recent decades, studies have mainly focused on adoptive immunotherapy using engineered T cells for the treatment of malignant diseases. Through gene engraftment of the patient's own T cells with chimeric antigen receptor(CAR),they can recognize tumor specific antigens effectively and eradicate selectively targeted cells in an MHC-independent fashion.To date, CAR-T cell therapy has shown great clinical utility in patients with B-cell leukemias. Owing to different CAR designs and tumor complex microenvironments, genetically redirected T cells may generate diverse biological properties and thereby impact their long-term clinical performance and outcome. Meanwhile some unexpected toxicities that result from CAR-T cell application have been examined and limited the curative effects. Diverse important parameters are closely related with adoptively transferred cell behaviors, including CAR-T cells homing, CAR constitutive signaling, T cell differentiation and exhaustion. Thus, understanding CARs molecular design to improve infused cell efficacy and safety is crucial to clinicians and patients who are considering this novel cancer therapeutics. In this review, the developments in CAR-T cell therapy and the limitations and perspectives in optimizing this technology towards clinical application are discussed.

Chimeric antigen receptor （CAR）-modified natural killer cell-based immunotherapy and immunological synapse formation in cancer and HIV

Cytotoxic T lymphocytes （CTLs） and natural killer （NK） cells contribute to the body＇s immune defenses. Current chimeric antigen receptor （CAR）-modified T cell immunotherapy shows strong promise for treating var- ious cancers and infectious diseases. Although CAR- modified NK cell immunotherapy is rapidly gaining attention, its clinical applications are mainly focused on preclinical investigations using the NK92 cell line. Despite recent advances in CAR-modified T cell immunotherapy, cost and severe toxicity have hindered its widespread use. To alleviate these disadvantages of CAR-modified T cell immunotherapy, additional cyto- toxic cell-mediated immunotherapies are urgently nee- ded. The unique biology of NK cells allows them to serve as a safe, effective, alternative immunotherapeutic strategy to CAR-modified T cells in the clinic. While the fundamental mechanisms underlying the cytotoxicity and side effects of CAR-modified T and NK cell immunotherapies remain poorly understood, the for- mation of the immunological synapse （IS） between CAR- modified T or NK cells and their susceptible target cells is known to be essential. The role of the IS in CAR T and NK cell immunotherapies will allow scientists to harness the power of CAR-modified T and NK cells to treat can- cer and infectious diseases. In this review, we highlight the potential applications of CAR-modified NK cells to treat cancer and human immunodeficiency virus （HIV）, and discuss the challenges and possible future directions of CAR-modified NK cell immunotherapy, as well as the importance of understanding the molecular mechanisms of CAR-modified T cell- or NK cell-medi- ated cytotoxicity and side effects, with a focus on the CAR-modified NK cell IS.

Phase I study of CAR-T cells with PD-1 and TCR disruption in mesothelin-positive solid tumors

Programmed cell death protein-1(PD-1)-mediated immunosuppression has been proposed to contribute to the limited clinical efficacy of chimeric antigen receptor T(CAR-T)cells in solid tumors.We generated PD-1 and T cell receptor(TCR)deficient mesothelin-specific CAR-T(MPTK-CAR-T)cells using CRISPR-Cas9 technology and evaluated them in a dose-escalation study.A total of 15 patients received one or more infusions of MPTK-CAR-T cells without prior lymphodepletion.No dose-limiting toxicity or unexpected adverse events were observed in any of the 15 patients.The best overall response was stable disease(2/15 patients).Circulating MPTK-CAR-T cells peaked at days 7–14 and became undetectable beyond 1 month.TCR-positive CAR-T cells rather than TCR-negative CAR-T cells were predominantly detected in effusion or peripheral blood from three patients after infusion.We further confirmed the reduced persistence of TCR-deficient CAR-T cells in animal models.Our results establish the preliminary feasibility and safety of CRISPR-engineered CAR-T cells with PD-1 disruption and suggest that the natural TCR plays an important role in the persistence of CAR-T cells when treating solid tumors.

Clinical development of CAR T cell therapy in China:2020 update

Chimeric antigen receptor(CAR)T-cell therapy has achieved significant success in the treatment of hematological malignancies.In recent years,fast-growing CAR T clinical trials have actively explored their potential application scenarios.According to the data from the clinicaltrials.gov website,China became the country with the most registered CAR T trials in September 2017.As of June 30,2020,the number of registered CAR T trials in China has reached 357.In addition,as many as 150 other CAR T trials have been registered on ChiCTR.Although CAR T therapy is flourishing in China,there are still some problems that cannot be ignored.In this review,we aim to systematically summarize the clinical practice of CAR T-cell therapy in China.This review will provide an informative reference for colleagues in the field,and a better understanding of the history and current situation will help us more reasonably conduct research and promote cooperation.

The model of cytokine release syndrome in CAR T-cell treatment for B-cell non-Hodgkin lymphoma

Chimeric antigen receptor T(CAR T)cell therapy has demonstrated efficacy in the treatment of haematologic malignancies.However,the accompanying adverse events,the most common of which is cytokine release syndrome(CRS),substantially limit its wide application.Due to its unique physiological characteristics,CRS in CAR T-cell treatment for B-cell non-Hodgkin lymphoma(BNHL)may exhibit some special features.Although existing guidelines had greatly promoted the recognition and management of CRS,many recommendations are not fully applicable to B-NHL.Therefore,it is imperative to identify responses that are specific to CRS observed following CAR T treatment for B-NHL.Based on underlying biological processes and known pathophysiological mechanisms,we tentatively propose a new model to illustrate the occurrence and evolution of CAR T-cell-therapy-related CRS in BNHL.In this model,tumour burden and bone marrow suppression are considered determinants of CRS.Novel phenomena after CAR T-cell infusion(such as local inflammatory response)are further identified.The proposed model will help us better understand the basic biology of CRS and recognize and manage it more rationally.

Targeting cancer stem cells by using chimeric antigen receptor-modified T cells： a potential and curable approach for cancer treatment

Cancer stem cells （CSCs）, a subpopulation of tumor cells, have self-renewal and multi-lineage differentiation abilities that play an important role in cancer initiation, mainte- nance, and metastasis. An accumulation of evidence indicates that CSCs can cause conventional therapy fail- ure and cancer recurrence because of their treatment resistance and self-regeneration characteristics. There- fore, approaches that specifically and efficiently eliminate CSCs to achieve a durable clinical response are urgently needed. Currently, treatments with chimeric antigen receptor-modified T （CART） cells have shown successful clinical outcomes in patients with hematologic malignan- cies, and their safety and feasibility in solid tumors was confirmed. In this review, we will discuss in detail the possibility that CART cells inhibit CSCs by specifically targeting their cell surface markers, which will ultimately improve the clinical response for patients with various types of cancer. A number of viewpoints were summarized to promote the application of CSC-targeted CART cells in clinical cancer treatment. This review covers the key aspects of CSC-targeted CART cells against cancers in accordance with the premise of the model, from bench to bedside and back to bench.