scholarly journals Adoptive Immunotherapy beyond CAR T-Cells

Cancers ◽  
2021 ◽  
Vol 13 (4) ◽  
pp. 743
Author(s):  
Aleksei Titov ◽  
Ekaterina Zmievskaya ◽  
Irina Ganeeva ◽  
Aygul Valiullina ◽  
Alexey Petukhov ◽  
...  
Keyword(s):  
T Cells ◽  
T Cell ◽  
B Cell ◽  
Solid Tumors ◽  
Adoptive Immunotherapy ◽  
Γδ T Cells ◽  
Car T Cells ◽  
Car T Cell ◽  
Cell Immunotherapy ◽  
Car T

Adoptive cell immunotherapy (ACT) is a vibrant field of cancer treatment that began progressive development in the 1980s. One of the most prominent and promising examples is chimeric antigen receptor (CAR) T-cell immunotherapy for the treatment of B-cell hematologic malignancies. Despite success in the treatment of B-cell lymphomas and leukemia, CAR T-cell therapy remains mostly ineffective for solid tumors. This is due to several reasons, such as the heterogeneity of the cellular composition in solid tumors, the need for directed migration and penetration of CAR T-cells against the pressure gradient in the tumor stroma, and the immunosuppressive microenvironment. To substantially improve the clinical efficacy of ACT against solid tumors, researchers might need to look closer into recent developments in the other branches of adoptive immunotherapy, both traditional and innovative. In this review, we describe the variety of adoptive cell therapies beyond CAR T-cell technology, i.e., exploitation of alternative cell sources with a high therapeutic potential against solid tumors (e.g., CAR M-cells) or aiming to be universal allogeneic (e.g., CAR NK-cells, γδ T-cells), tumor-infiltrating lymphocytes (TILs), and transgenic T-cell receptor (TCR) T-cell immunotherapies. In addition, we discuss the strategies for selection and validation of neoantigens to achieve efficiency and safety. We provide an overview of non-conventional TCRs and CARs, and address the problem of mispairing between the cognate and transgenic TCRs. Finally, we summarize existing and emerging approaches for manufacturing of the therapeutic cell products in traditional, semi-automated and fully automated Point-of-Care (PoC) systems.

scholarly journals 221 CRISPR screen identifies loss of IFNγR signaling and downstream adhesion as a resistance mechanism to CAR T-cell cytotoxicity in solid but not liquid tumors

2021 ◽  
Vol 9 (Suppl 3) ◽  
pp. A234-A234
Author(s):  
Rebecca Larson ◽  
Michael Kann ◽  
Stefanie Bailey ◽  
Nicholas Haradhvala ◽  
Kai Stewart ◽  
...  
Keyword(s):  
T Cells ◽  
T Cell ◽  
B Cell ◽  
Solid Tumors ◽  
T Cell Therapy ◽  
Car T Cells ◽  
Car T Cell ◽  
Car T Cell Therapy ◽  
Car T

BackgroundChimeric Antigen Receptor (CAR) therapy has had a transformative impact on the treatment of hematologic malignancies1–6 but success in solid tumors remains elusive. We hypothesized solid tumors have cell-intrinsic resistance mechanisms to CAR T-cell cytotoxicity.MethodsTo systematically identify resistance pathways, we conducted a genome-wide CRISPR knockout screen in glioblastoma cells, a disease where CAR T-cells have had limited efficacy.7 8 We utilized the glioblastoma cell line U87 and targeted endogenously expressed EGFR with CAR T-cells generated from 6 normal donors for the screen. We validated findings in vitro and in vivo across a variety of human tumors and CAR T-cell antigens.ResultsLoss of genes in the interferon gamma receptor (IFNγR) signaling pathway (IFNγR1, JAK1, JAK2) rendered U87 cells resistant to CAR T-cell killing in vitro. IFNγR1 knockout tumors also showed resistance to CAR T cell treatment in vivo in a second glioblastoma line U251 in an orthotopic model. This phenomenon was irrespective of CAR target as we also observed resistance with IL13Ralpha2 CAR T-cells. In addition, resistance to CAR T-cell cytotoxicity through loss of IFNγR1 applied more broadly to solid tumors as pancreatic cell lines targeted with either Mesothelin or EGFR CAR T-cells also showed resistance. However, loss of IFNγR signaling did not impact sensitivity of liquid tumor lines (leukemia, lymphoma or multiple myeloma) to CAR T-cells in vitro or in an orthotopic model of leukemia treated with CD19 CAR. We isolated the effects of decreased cytotoxicity of IFNγR1 knockout glioblastoma tumors to be cancer-cell intrinsic because CAR T-cells had no observable differences in proliferation, activation (CD69 and LFA-1), or degranulation (CD107a) when exposed to wildtype versus knockout tumors. Using transcriptional profiling, we determined that glioblastoma cells lacking IFNγR1 had lower upregulation of cell adhesion pathways compared to wildtype glioblastoma cells after exposure to CAR T-cells. We found that loss of IFNγR1 reduced CAR T-cell binding avidity to glioblastoma.ConclusionsThe critical role of IFNγR signaling for susceptibility of solid tumors to CAR T-cells is surprising given that CAR T-cells do not require traditional antigen-presentation pathways. Instead, in glioblastoma tumors, IFNγR signaling was required for sufficient adhesion of CAR T-cells to mediate productive cytotoxicity. Our work demonstrates that liquid and solid tumors differ in their interactions with CAR T-cells and suggests that enhancing T-cell/tumor interactions may yield improved responses in solid tumors.AcknowledgementsRCL was supported by T32 GM007306, T32 AI007529, and the Richard N. Cross Fund. ML was supported by T32 2T32CA071345-21A1. SRB was supported by T32CA009216-38. NJH was supported by the Landry Cancer Biology Fellowship. JJ is supported by a NIH F31 fellowship (1F31-MH117886). GG was partially funded by the Paul C. Zamecnik Chair in Oncology at the Massachusetts General Hospital Cancer Center and NIH R01CA 252940. MVM and this work is supported by the Damon Runyon Cancer Research Foundation, Stand Up to Cancer, NIH R01CA 252940, R01CA238268, and R01CA249062.ReferencesMaude SL, et al. Tisagenlecleucel in children and young adults with B-cell lymphoblastic leukemia. N Engl J Med 2018;378:439–448.Neelapu SS, et al. Axicabtagene ciloleucel CAR T-cell therapy in refractory large B-cell lymphoma. N Engl J Med 2017;377:2531–2544.Locke FL, et al. Long-term safety and activity of axicabtagene ciloleucel in refractory large B-cell lymphoma (ZUMA-1): a single-arm, multicentre, phase 1–2 trial. The Lancet Oncology 2019;20:31–42.Schuster SJ, et al. Chimeric antigen receptor T cells in refractory B-cell lymphomas. N Engl J Med 2017;377:2545–2554.Wang M, et al. KTE-X19 CAR T-cell therapy in relapsed or refractory mantle-cell lymphoma. N Engl J Med 2020;382:1331–1342.Cohen AD, et al. B cell maturation antigen-specific CAR T cells are clinically active in multiple myeloma. J Clin Invest 2019;129:2210–2221.Bagley SJ, et al. CAR T-cell therapy for glioblastoma: recent clinical advances and future challenges. Neuro-oncology 2018;20:1429–1438.Choi BD, et al. Engineering chimeric antigen receptor T cells to treat glioblastoma. J Target Ther Cancer 2017;6:22–25.Ethics ApprovalAll human samples were obtained with informed consent and following institutional guidelines under protocols approved by the Institutional Review Boards (IRBs) at the Massachusetts General Hospital (2016P001219). Animal work was performed according to protocols approved by the Institutional Animal Care and Use Committee (IACUC) (2015N000218 and 2020N000114).

scholarly journals Obstacles and Coping Strategies of CAR-T Cell Immunotherapy in Solid Tumors

2021 ◽  
Vol 12 ◽  
Author(s):  
Lele Miao ◽  
Zhengchao Zhang ◽  
Zhijian Ren ◽  
Futian Tang ◽  
Yumin Li
Keyword(s):  
T Cells ◽  
T Cell ◽  
Solid Tumors ◽  
Hematologic Malignancies ◽  
Car T Cells ◽  
Car T Cell ◽  
Cell Immunotherapy ◽  
Car T ◽  
And Coping ◽  
T Cell Immunotherapy

Chimeric antigen receptor (CAR) T-cell immunotherapy refers to an adoptive immunotherapy that has rapidly developed in recent years. It is a novel type of treatment that enables T cells to express specific CARs on their surface, then returns these T cells to tumor patients to kill the corresponding tumor cells. Significant strides in CAR-T cell immunotherapy against hematologic malignancies have elicited research interest among scholars in the treatment of solid tumors. Nonetheless, in contrast with the efficacy of CAR-T cell immunotherapy in the treatment of hematologic malignancies, its general efficacy against solid tumors is insignificant. This has been attributed to the complex biological characteristics of solid tumors. CAR-T cells play a better role in solid tumors, for instance by addressing obstacles including the lack of specific targets, inhibition of tumor microenvironment (TME), homing barriers of CAR-T cells, differentiation and depletion of CAR-T cells, inhibition of immune checkpoints, trogocytosis of CAR-T cells, tumor antigen heterogeneity, etc. This paper reviews the obstacles influencing the efficacy of CAR-T cell immunotherapy in solid tumors, their mechanism, and coping strategies, as well as economic restriction of CAR-T cell immunotherapy and its solutions. It aims to provide some references for researchers to better overcome the obstacles that affect the efficacy of CAR-T cells in solid tumors.

scholarly journals Engineering Metabolism of Chimeric Antigen Receptor (CAR) Cells for Developing Efficient Immunotherapies

Cancers ◽  
2021 ◽  
Vol 13 (5) ◽  
pp. 1123
Author(s):  
Joslyn L. Mangal ◽  
Jamie L. Handlos ◽  
Arezoo Esrafili ◽  
Sahil Inamdar ◽  
Sidnee Mcmillian ◽  
...  
Keyword(s):  
T Cells ◽  
T Cell ◽  
B Cell ◽  
Solid Tumors ◽  
Chimeric Antigen Receptor ◽  
Immune Cells ◽  
Hematological Malignancies ◽  
Car T Cells ◽  
Car T Cell ◽  
Car T

Chimeric antigen receptor (CAR) T cell-based therapies have shown tremendous advancement in clinical and pre-clinical studies for the treatment of hematological malignancies, such as the refractory of pre-B cell acute lymphoblastic leukemia (B-ALL), chronic lymphocytic leukemia (CLL), and large B cell lymphoma (LBCL). However, CAR T cell therapy for solid tumors has not been successful clinically. Although, some research efforts, such as combining CARs with immune checkpoint inhibitor-based therapy, have been used to expand the application of CAR T cells for the treatment of solid tumors. Importantly, further understanding of the coordination of nutrient and energy supplies needed for CAR T cell expansion and function, especially in the tumor microenvironment (TME), is greatly needed. In addition to CAR T cells, there is great interest in utilizing other types of CAR immune cells, such as CAR NK and CAR macrophages that can infiltrate solid tumors. However, the metabolic competition in the TME between cancer cells and immune cells remains a challenge. Bioengineering technologies, such as metabolic engineering, can make a substantial contribution when developing CAR cells to have an ability to overcome nutrient-paucity in the solid TME. This review introduces technologies that have been used to generate metabolically fit CAR-immune cells as a treatment for hematological malignancies and solid tumors, and briefly discusses the challenges to treat solid tumors with CAR-immune cells.

scholarly journals CARTmath—A Mathematical Model of CAR-T Immunotherapy in Preclinical Studies of Hematological Cancers

Cancers ◽  
2021 ◽  
Vol 13 (12) ◽  
pp. 2941
Author(s):  
Luciana R. C. Barros ◽  
Emanuelle A. Paixão ◽  
Andrea M. P. Valli ◽  
Gustavo T. Naozuka ◽  
Artur C. Fassoni ◽  
...  
Keyword(s):  
Mathematical Model ◽  
T Cells ◽  
T Cell ◽  
Mouse Models ◽  
In Silico ◽  
Car T Cells ◽  
Car T Cell ◽  
Cell Immunotherapy ◽  
Car T ◽  
T Cell Immunotherapy

Immunotherapy has gained great momentum with chimeric antigen receptor T cell (CAR-T) therapy, in which patient’s T lymphocytes are genetically manipulated to recognize tumor-specific antigens, increasing tumor elimination efficiency. In recent years, CAR-T cell immunotherapy for hematological malignancies achieved a great response rate in patients and is a very promising therapy for several other malignancies. Each new CAR design requires a preclinical proof-of-concept experiment using immunodeficient mouse models. The absence of a functional immune system in these mice makes them simple and suitable for use as mathematical models. In this work, we develop a three-population mathematical model to describe tumor response to CAR-T cell immunotherapy in immunodeficient mouse models, encompassing interactions between a non-solid tumor and CAR-T cells (effector and long-term memory). We account for several phenomena, such as tumor-induced immunosuppression, memory pool formation, and conversion of memory into effector CAR-T cells in the presence of new tumor cells. Individual donor and tumor specificities are considered uncertainties in the model parameters. Our model is able to reproduce several CAR-T cell immunotherapy scenarios, with different CAR receptors and tumor targets reported in the literature. We found that therapy effectiveness mostly depends on specific parameters such as the differentiation of effector to memory CAR-T cells, CAR-T cytotoxic capacity, tumor growth rate, and tumor-induced immunosuppression. In summary, our model can contribute to reducing and optimizing the number of in vivo experiments with in silico tests to select specific scenarios that could be tested in experimental research. Such an in silico laboratory is an easy-to-run open-source simulator, built on a Shiny R-based platform called CARTmath. It contains the results of this manuscript as examples and documentation. The developed model together with the CARTmath platform have potential use in assessing different CAR-T cell immunotherapy protocols and its associated efficacy, becoming an accessory for in silico trials.

scholarly journals Innovative CAR-T Cell Therapy for Solid Tumor; Current Duel between CAR-T Spear and Tumor Shield

Cancers ◽  
2020 ◽  
Vol 12 (8) ◽  
pp. 2087
Author(s):  
Yuna Jo ◽  
Laraib Amir Ali ◽  
Ju A Shim ◽  
Byung Ha Lee ◽  
Changwan Hong
Keyword(s):  
T Cells ◽  
T Cell ◽  
Tumor Microenvironment ◽  
Solid Tumors ◽  
T Cell Therapy ◽  
Car T Cell ◽  
Cell Immunotherapy ◽  
Car T Cell Therapy ◽  
Car T ◽  
T Cell Immunotherapy

Novel engineered T cells containing chimeric antigen receptors (CAR-T cells) that combine the benefits of antigen recognition and T cell response have been developed, and their effect in the anti-tumor immunotherapy of patients with relapsed/refractory leukemia has been dramatic. Thus, CAR-T cell immunotherapy is rapidly emerging as a new therapy. However, it has limitations that prevent consistency in therapeutic effects in solid tumors, which accounts for over 90% of all cancer patients. Here, we review the literature regarding various obstacles to CAR-T cell immunotherapy for solid tumors, including those that cause CAR-T cell dysfunction in the immunosuppressive tumor microenvironment, such as reactive oxygen species, pH, O2, immunosuppressive cells, cytokines, and metabolites, as well as those that impair cell trafficking into the tumor microenvironment. Next-generation CAR-T cell therapy is currently undergoing clinical trials to overcome these challenges. Therefore, novel approaches to address the challenges faced by CAR-T cell immunotherapy in solid tumors are also discussed here.

scholarly journals Absolute lymphocyte count proliferation kinetics after CAR T-cell infusion impact response and relapse

2021 ◽  
Vol 5 (8) ◽  
pp. 2128-2136
Author(s):  
Sophia Faude ◽  
Jane Wei ◽  
Kavitha Muralidharan ◽  
Xiaoming Xu ◽  
Gerald Wertheim ◽  
...  
Keyword(s):  
T Cells ◽  
T Cell ◽  
B Cell ◽  
Lymphocyte Count ◽  
Absolute Lymphocyte Count ◽  
Rapid Expansion ◽  
Proliferation Kinetics ◽  
Car T Cells ◽  
Car T Cell ◽  
Car T

Abstract CD19-directed chimeric antigen receptor (CAR) T cells show characteristic proliferation kinetics after infusion that correlate with response. Clearance of circulating disease, B-cell aplasia (BCA), and cytokine release syndrome (CRS) are used to observe CAR T-cell function, given the lack of commercial CAR T-cell measurement assays. We investigated the utility of common hematology laboratory parameters in 166 patients with B-cell acute lymphoblastic leukemia (B-ALL) who were treated with CAR T-cell therapy targeting CD19. CAR T-cell infusion was followed by disappearance of circulating blasts in 86% of patients at a median of 6 days. After a lag phase, there was a rapid expansion in absolute lymphocyte count (ALC) in the second week that coincided with the appearance of atypical lymphocytes. The expansion phase was followed by a contraction phase with a concomitant decrease in atypical lymphocytes. In vitro CAR T-cell studies showed similar kinetics and morphological changes. Peak ALC and overall expansion was greater in sustained responders compared with that in nonresponders. Patients with early loss of BCA and those with eventual CD19+ minimal residual disease/relapse showed lower overall lymphocyte expansion compared with the controls. Pleomorphic lymphocytosis was noted in the cerebrospinal fluid at post-CAR time points. We conclude that lymphocyte counts and differential can also be used to evaluate CAR T-cell expansion after infusion, along with BCA and CRS. This is the first report to characterize the morphology of CAR T cells and determine the utility of lymphocyte kinetics.

scholarly journals Efficacy and Safety of JWCAR029 in Adult Patients with Relapsed and Refractory B-Cell Non-Hodgkin Lymphoma

Blood ◽  
2018 ◽  
Vol 132 (Supplement 1) ◽  
pp. 4187-4187 ◽  
Author(s):  
Zixun Yan ◽  
Wen Wang ◽  
Zhong Zheng ◽  
Ming Hao ◽  
Su Yang ◽  
...  
Keyword(s):  
T Cells ◽  
T Cell ◽  
B Cell ◽  
Hodgkin Lymphoma ◽  
Dose Level ◽  
Car T Cells ◽  
Car T Cell ◽  
Non Hodgkin Lymphoma ◽  
Car T

Abstract Introduction JWCAR029 is a novel CD19-directed 4-1BB stimulated chimeric antigen receptor T (CAR-T) cell type, which is different from JWCAR017 with independent production of CD4 and CD8 T cells and transfusion in non-fixed ratio. We conducted a single arm, open-label, dose escalation Phase I trial of JWCAR029 in relapsed and refractory B-cell non-Hodgkin lymphoma (NCT03355859). Methods From January to July 2018, 10 patients have been enrolled in this trial, including eight diffused large B cell lymphoma (DLBCL) and two MALT lymphoma, with median age of 47 years (range 32 to 59 years). All the patients received immunochemotherapy as induction and more than two lines of salvage treatment. Two patients received bridging chemotherapy after T-cell collection due to rapid tumor progression, followed by re-evaluation before CAR-T cell infusion. Lymphodepletion preconditioning was accomplished by fludarabine 25mg/m2/d and cyclophosphamide 250mg/m2/d on Day-4 to D-2, followed by CAR-T cell infusion on Day0. JWCAR029 was administrated as a single infusion in escalation dose levels, from 2.5×107 CAR-T cells (dose level 1, DL1) to 5.0×107 CAR-T cells (dose level 2, DL2) and to 1.0×108 CAR-T cells (dose level 3, DL3) according to mTPI-2 algorithm. Circulating blood count, serum biochemistry, and coagulation status were follow-up after infusion. Cytokines were assessed on a Luminex platform. Tumor evaluation was performed on Day 29 by PET-CT. PK data were detected by flow cytometry and real-time quantitative polymerase chain reaction system. All the adverse events were recorded. The study was approved by the Shanghai Rui Jin Hospital Review Board with informed consent obtained in accordance with the Declaration of Helsinki. Results The demographic characteristics of the patients were demonstrated in Table 1. Among six evaluable patients (3 of DL1 and 3 of DL2), the ORR was 100% on Day 29, including four complete remission and 2 partial remission. Cytokine release syndrome (CRS) was 100% in Gr 1, with main symptoms as fever (<39.0 degrees), fatigue, and muscle soreness. No neurotoxicity was observed. Four of the six patients with fever >38.0 degrees used prophylactic IL-6 Inhibitor (8mg/kg, ACTEMRA, two patients administered twice). No patients received steroids. The CRS showed no difference between dose level groups (p>0.99). Adverse effects included leukopenia (Gr 3-4: 83.3%, Gr 1-2: 16.7%), hypofibrinogenemia (Gr 1: 16.7%, Gr 2-4: 0%), liver dysfunction (Gr 1: 33.3%, Gr 2-4: 0%), elevated CRP (Gr 1: 83.3%, Gr 2-4: 0%), ferritin (Gr 1-2: 83.3%, Gr 2-4: 0%), or IL-6 (Gr 1-2:100%, Gr 3-4: 0%, Table 2). Conclusion Although long-term follow-up was needed, the preliminary data of six patients in this trial have demonstrated high response rates and safety of JWCAR029 in treating relapsed and refractory B-cell non-Hodgkin lymphoma. Disclosures Hao: JW Therapeutics: Employment, Equity Ownership.

scholarly journals CAR T-cell therapy of solid tumors: promising approaches to modulating antitumor activity of CAR T cells

2019 ◽  
pp. 5-12 ◽  
Author(s):  
Ya.Yu. Kiseleva ◽  
A.M. Shishkin ◽  
A.V. Ivanov ◽  
T.M. Kulinich ◽  
V.K. Bozhenko
Keyword(s):  
T Cells ◽  
T Cell ◽  
Cell Therapy ◽  
Solid Tumors ◽  
Functional Activity ◽  
T Cell Therapy ◽  
Car T Cells ◽  
Car T Cell ◽  
Car T Cell Therapy ◽  
Car T

Adoptive immunotherapy that makes use of genetically modified autologous T cells carrying a chimeric antigen receptor (CAR) with desired specificity is a promising approach to the treatment of advanced or relapsed solid tumors. However, there are a number of challenges facing the CAR T-cell therapy, including the ability of the tumor to silence the expression of target antigens in response to the selective pressure exerted by therapy and the dampening of the functional activity of CAR T cells by the immunosuppressive tumor microenvironment. This review discusses the existing gene-engineering approaches to the modification of CAR T-cell design for 1) creating universal “switchable” synthetic receptors capable of attacking a variety of target antigens; 2) enhancing the functional activity of CAR T cells in the immunosuppressive microenvironment of the tumor by silencing the expression of inhibiting receptors or by stimulating production of cytokines.

Modeling and simulation of the “IL-36 cytokine” and CAR-T cells interplay in cancer onset

2021 ◽  
Author(s):  
Khaled A. Al-Utaibi ◽  
Alessandro Nutini ◽  
Ayesha Sohail ◽  
Robia Arif ◽  
Sümeyye Tunc ◽  
...  
Keyword(s):  
T Cells ◽  
T Cell ◽  
Adoptive Immunotherapy ◽  
Checkpoint Inhibitors ◽  
Antitumor Action ◽  
Adoptive Therapy ◽  
T Cell Therapy ◽  
Car T Cells ◽  
Car T Cell ◽  
Car T

Background: CAR-T cells are chimeric antigen receptor (CAR)-T cells; they are target-specific engineered cells on tumor cells and produce T cell-mediated antitumor responses. CAR-T cell therapy is the “first-line” therapy in immunotherapy for the treatment of highly clonal neoplasms such as lymphoma and leukemia. This adoptive therapy is currently being studied and tested even in the case of solid tumors such as osteosarcoma since, precisely for this type of tumor, the use of immune checkpoint inhibitors remained disappointing. Although CAR-T is a promising therapeutic technique, there are therapeutic limits linked to the persistence of these cells and to the tumor’s immune escape. CAR-T cell engineering techniques are allowed to express interleukin IL-36, and seem to be much more efficient in antitumoral action. IL-36 is involved in the long-term antitumor action, allowing CAR-T cells to be more efficient in their antitumor action due to a “cross-talk” action between the “IL-36/dendritic cells” axis and the adaptive immunity. Methods: This analysis makes the model useful for evaluating cell dynamics in the case of tumor relapses or specific understanding of the action of CAR-T cells in certain types of tumor. The model proposed here seeks to quantify the action and interaction between the three fundamental elements of this antitumor activity induced by this type of adoptive immunotherapy: IL-36, “armored” CAR-T cells (i.e., engineered to produce IL-36) and the tumor cell population, focusing exclusively on the action of this interleukin and on the antitumor consequences of the so modified CAR-T cells. Mathematical model was developed and numerical simulations were carried out during this research. The development of the model with stability analysis by conditions of Routh–Hurwitz shows how IL-36 makes CAR-T cells more efficient and persistent over time and more effective in the antitumoral treatment, making therapy more effective against the “solid tumor”. Findings: Primary malignant bone tumors are quite rare (about 3% of all tumors) and the vast majority consist of osteosarcomas and Ewing’s sarcoma and, approximately, the 20% of patients undergo metastasis situations that is the most likely cause of death. Interpretation: In bone tumor like osteosarcoma, there is a variation of the cellular mechanical characteristics that can influence the efficacy of chemotherapy and increase the metastatic capacity; an approach related to adoptive immunotherapy with CAR-T cells may be a possible solution because this type of therapy is not influenced by the biomechanics of cancer cells which show peculiar characteristics.

scholarly journals P01.22 Extending CAR T cell therapy applications via drug inducible control of transgene expression

2020 ◽  
Vol 8 (Suppl 2) ◽  
pp. A18.2-A19
Author(s):  
B Kotter ◽  
N Werchau ◽  
W Krueger ◽  
A Roy ◽  
J Mittelstaet ◽  
...  
Keyword(s):  
T Cells ◽  
T Cell ◽  
B Cell ◽  
Transgene Expression ◽  
Car T Cells ◽  
Car T Cell ◽  
Car T ◽  
Part Time ◽  
Anti Cd20

BackgroundAdoptive transfer of chimeric antigen receptor (CAR)-modified T cells has emerged as a promising treatment modality for a broad range of cancers highlighted by the approval of Kymriah™ and Yescarta™ for the treatment of B cell malignancies. However, lack of control of CAR T cell function and consequent excessive inflammation in patients can result in severe side effects especially when targeting tumor-associated rather than tumor-specific antigens. Thus, temporal and tunable control of CAR activity is of major importance for the clinical translation of innovative CAR designs. While the activation of suicide switches results in the apoptotic elimination of the transferred cells, other strategies, e.g. anti-tag CARs or small molecule-gated CARs, enable the reversible control of CAR-mediated function at the protein level but are restricted to a particular CAR design. Focusing on the control of expression rather than CAR signaling, transcriptional regulators represent a versatile tool facilitating a wide range of CAR T cell applications.Materials and MethodsTo maintain control over the infused CAR T cell product and mitigate risks for the patient, we describe here the development of an inducible switch system for the transcriptional regulation of transgene expression in primary, human T cells. Chemically regulated synthetic transcription factors composed of a zinc finger DNA-binding domain, an inducible control domain and a transcription activation domain were designed, screened for functionality, and evaluated in T cells regarding their potential to control CAR expression both in vitro and in vivo.ResultsBy screening, we identified a synthetic transcription factor, which shows high transcriptional output in T cells in the presence of a clinically relevant inducer drug and absence of background activity in the non-induced state. Using this system we were able to control the expression of a CAR recognizing the CD20 antigen present on B cells and B cell leukemic blasts. The addition of the inducer drug resulted in rapid expression of the anti-CD20 CAR on the T cell surface. Moreover, inducible anti-CD20 CAR T cells executed cytolytic activity against CD20 positive target cells and secreted cytokines upon stimulation in vitro. Effectivity in co-cultures was thereby comparable to T cells expressing the anti-CD20 CAR under a conventional constitutive promoter. Furthermore, we could fine-tune CAR activity by titrating the inducer concentration. By defining the time-point of induction, modulation of the onset of therapy was achieved. Upon inducer drug discontinuation, inducible CD20 CAR T cells lost CAR expression and concurrently all CAR-related functions, indicating that the ‘on’ and ‘off’ status can be tightly controlled by the administration of the drug. After pausing of CAR T cell-mediated activity, we could re-induce CAR expression suggesting complete reversibility of effector function. Finally, we were able to show that inducible CD20 CAR T cells mediate a significant, strictly inducer-dependent antitumor activity in a well-established mouse model of B cell lymphoma.ConclusionsThe zinc-finger-based transcriptional control system investigated in this study provides small molecule-inducible control over a therapeutically relevant anti-CD20 CAR in primary T cells in a time- and dose-dependent manner. The tight regulation of CAR expression will pave the way for safer cellular therapies.Disclosure InformationB. Kotter: A. Employment (full or part-time); Significant; Miltenyi Biotec B.V. & Co. KG. N. Werchau: A. Employment (full or part-time); Significant; Miltenyi Biotec B.V. & Co. KG. W. Krueger: A. Employment (full or part-time); Significant; Lentigen Technology Inc. A. Roy: A. Employment (full or part-time); Significant; Lentigen Technology Inc. J. Mittelstaet: A. Employment (full or part-time); Significant; Miltenyi Biotec B.V. & Co. KG. A. Kaiser: A. Employment (full or part-time); Significant; Miltenyi Biotec B.V. & Co. KG.

Sign in / Sign up

Export Citation Format

Share Document