IFN-γ surmounts PD-L1/PD1 inhibition to CAR-T cell therapy by upregulating ICAM-1 on tumor cells

CAR-T cell therapy is the most advanced way to treat therapy resistant hematologic cancers, in particular B cell lymphomas and leukemias, with high efficiency. Donor T cells equipped ex vivo with chimeric receptor recognize target tumor cells and kill them using lytic granules. CAR-T cells that recognize CD19 marker of B cells (CD19 CAR-T) are considered the gold standard of CAR-T therapy and are approved by FDA. But in some cases, CD19 CAR-T cell therapy fails due to immune suppressive microenvironment. It is shown that tumor cells upregulate expression of PD-L1 surface molecule that binds and increases level and signal provided by PD-1 receptor on the surface of therapeutic CAR-T cells. Induction of this negative signaling results in functional impairment of cytotoxic program in CAR-T cells. Multiple attempts were made to block PD-1 signaling by reducing binding or surface level of PD-1 in CAR-T cells by various means. In this study we co-expressed CD19-CAR with PD-1-specific VHH domain of anti-PD-1 nanobody to block PD-1/PD-L1 signaling in CD19 CAR-T cells. Unexpectedly, despite increased activation of CAR-T cells with low level of PD-1, these T cells had reduced survival and diminished cytotoxicity. Functional impairment caused by disrupted PD-1 signaling was accompanied by faster maturation and upregulation of exhaustion marker TIGIT in CAR-T cells. We conclude that PD-1 in addition to its direct negative effect on CAR-induced signaling is required for attenuation of strong stimulation leading to cell death and functional exhaustion. These observations suggest that PD-1 downregulation should not be considered as the way to improve the quality of therapeutic CAR-T cells.

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Overview of the pre-clinical and clinical studies about the use of CAR-T cell therapy of cancer combined with oncolytic viruses

World Journal of Surgical Oncology ◽

10.1186/s12957-021-02486-x ◽

2022 ◽

Vol 20 (1) ◽

Author(s):

Ali Zarezadeh Mehrabadi ◽

Fatemeh Roozbahani ◽

Reza Ranjbar ◽

Mahdieh Farzanehpour ◽

Alireza Shahriary ◽

...

Keyword(s):

T Cells ◽

T Cell ◽

Cell Therapy ◽

Tumor Cells ◽

Oncolytic Viruses ◽

Therapeutic Approaches ◽

T Cell Therapy ◽

Car T Cell ◽

Car T Cell Therapy ◽

Car T

Abstract Background Cancer is one of the critical issues of the global health system with a high mortality rate even with the available therapies, so using novel therapeutic approaches to reduce the mortality rate and increase the quality of life is sensed more than ever. Main body CAR-T cell therapy and oncolytic viruses are innovative cancer therapeutic approaches with fewer complications than common treatments such as chemotherapy and radiotherapy and significantly improve the quality of life. Oncolytic viruses can selectively proliferate in the cancer cells and destroy them. The specificity of oncolytic viruses potentially maintains the normal cells and tissues intact. T-cells are genetically manipulated and armed against the specific antigens of the tumor cells in CAR-T cell therapy. Eventually, they are returned to the body and act against the tumor cells. Nowadays, virology and oncology researchers intend to improve the efficacy of immunotherapy by utilizing CAR-T cells in combination with oncolytic viruses. Conclusion Using CAR-T cells along with oncolytic viruses can enhance the efficacy of CAR-T cell therapy in destroying the solid tumors, increasing the permeability of the tumor cells for T-cells, reducing the disturbing effects of the immune system, and increasing the success chance in the treatment of this hazardous disease. In recent years, significant progress has been achieved in using oncolytic viruses alone and in combination with other therapeutic approaches such as CAR-T cell therapy in pre-clinical and clinical investigations. This principle necessitates a deeper consideration of these treatment strategies. This review intends to curtly investigate each of these therapeutic methods, lonely and in combination form. We will also point to the pre-clinical and clinical studies about the use of CAR-T cell therapy combined with oncolytic viruses.

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Destabilization of CAR T-cell treatment efficacy in the presence of dexamethasone

10.1101/2021.10.01.462697 ◽

2021 ◽

Author(s):

Alexander B. Brummer ◽

Xin Yang ◽

Eric Ma ◽

Margarita Gutova ◽

Christine E. Brown ◽

...

Keyword(s):

T Cells ◽

T Cell ◽

Cell Therapy ◽

Tumor Cells ◽

T Cell Therapy ◽

Car T Cells ◽

Car T Cell ◽

Car T Cell Therapy ◽

Car T

AbstractChimeric antigen receptor (CAR) T-cell therapy is potentially an effective targeted immunotherapy for glioblastoma, yet there is presently little known about the efficacy of CAR T-cell treatment when combined with the widely used anti-inflammatory and immunosuppressant glucocorticoid, Dexamethasone. Here we present a mathematical model-based analysis of three patient-derived glioblastoma cell lines treated in vitro with CAR T-cells and Dexamethasone. Advanced in vitro experimental cell killing assay technologies allow for highly resolved temporal dynamics of tumor cells treated with CAR T-cells and Dexamethone, making this a valuable model system for studying the rich dynamics of nonlinear biological processes with translational applications. We model the system as a non-autonomous, two-species predator-prey interaction of tumor cells and CAR T-cells, with explicit time-dependence in the clearance rate of Dexamethasone. Using time as a bifurcation parameter, we show that (1) the presence of Dexamethasone destabilizes coexistence equilibria between CAR T-cells and tumor cells and (2) as Dexamethasone is cleared from the system, a stable coexistence equilibrium returns in the form of a Hopf bifurcation. With the model fit to experimental data, we demonstrate that high concentrations of Dexamethasone antagonizes CAR T-cell efficacy by exhausting, or reducing the activity of CAR T-cells, and by promoting tumor cell growth. Finally, we identify a critical threshold in the ratio of CAR T-cell death to CAR T-cell proliferation rates that predicts eventual treatment success or failure that may be used to guide the dose and timing of CAR T-cell therapy in the presence of Dexamethasone in patients.Author summaryBioengineering and gene-editing technologies have paved the way for advance immunotherapies that can target patient-specific tumor cells. One of these therapies, chimeric antigen receptor (CAR) T-cell therapy has recently shown promise in treating glioblastoma, an aggressive brain cancer often with poor patient prognosis. Dexamethasone is a commonly prescribed anti-inflammatory medication due to the health complications of tumor associated swelling in the brain. However, the immunosuppressant effects of Dexamethasone on the immunotherapeutic CAR T-cells are not well understood. To address this issue, we use mathematical modeling to study in vitro dynamics of Dexamethasone and CAR T-cells in three patient-derived glioblastoma cell lines. We find that in each cell line studied there is a threshold of tolerable Dexamethasone concentration. Below this threshold, CAR T-cells are successful at eliminating the cancer cells, while above this threshold, Dexamethasone critically inhibits CAR T-cell efficacy. Our modeling suggests that in the presence of Dexamethasone reduced CAR T-cell efficacy, or increased exhaustion, can occur and result in CAR T-cell treatment failure.

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Blockade of CD95/CD95L Death Signaling Enhances CAR T Cell Persistence and Antitumor Efficacy

Blood ◽

10.1182/blood-2019-122833 ◽

2019 ◽

Vol 134 (Supplement_1) ◽

pp. 3226-3226 ◽

Cited By ~ 1

Author(s):

Bailin He ◽

Lei Wang ◽

Brigitte Neuber ◽

Anita Schmitt ◽

Niclas Kneisel ◽

...

Keyword(s):

T Cells ◽

Cell Death ◽

T Cell ◽

Cell Therapy ◽

Tumor Cells ◽

T Cell Therapy ◽

Car T Cells ◽

Car T Cell ◽

Car T Cell Therapy ◽

Car T

Introduction Despite the encouraging outcome of anti-CD19 chimeric antigen receptor T (CAR T) cell therapy in patients with B cell malignancies, CAR T cell persistence remains a major clinical challenge. Activation-induced cell death (AICD) is a programmed cell death caused by the interaction of CD95 and CD95L. Through specific blocking of the CD95-CD95L pathway, the CD95L inhibitor APG101 (Asunercept, Apogenix AG, Heidelberg) could prevent activated T cells from AICD. APG101 is a fully human fusion protein consisting of the extracellular domain of CD95 receptor and the Fc domain of an IgG antibody. Thus, we evaluated whether a blockade of the CD95L pathway through APG101 might improve CAR T cell persistence and enhance antitumor efficacy. Methods Human peripheral blood mononuclear cells (PBMCs) from healthy donors were stimulated by plate-bound CD3 and CD28 antibodies, and thereafter transduced with a 3rd generation CD19.CAR.CD28.CD137zeta retroviral vector. An in vitro co-culture stress test assay was employed to assess the functional status and viability of CD19.CAR T cells upon repetitive stimulation with CD19+ tumor cells, i.e. Daudi cells. CAR T cells (5.0 x 105 per well) were co-cultured with tumor cells at a 1:1 E:T ratio (round I) in the presence of APG101. Additional tumor cells were supplied to the co-culture every 24 hours. After 3 rounds (72 hr) of stimulation, tumor cells (CD3-CD19+) and CAR T cells (CD3+CD19-) were harvested for FACS analysis. To assess the antigen-induced CAR T cell proliferation, CAR T cells were preloaded with Cell Trace Violet cytosolic dye and cocultured with tumor cells for 72 hours. Results Activation-induced cell death of CAR T cells was observed after repeated antigenic stimulation, accompanied by increased CD95L expression. CD4+ CAR T cells were more susceptible to AICD compared to CD8+ CAR T cells. But, there was no difference in the expression of CD95L between CD4+ and CD8+ CAR T cells. Interestingly, addition of APG101 significantly inhibited CD95L expression and resulted in a lower level of CAR T cell death. Importantly, APG101 did not hamper the activation and proliferation of CAR T cells but was able to restore CAR T cell viability. The expression of PD1, TIM3 and LAG3 were also up-regulated after successive stimulation, however, their expression on CAR T cells were not influenced by APG101. After 3 days of co-culture, the number of CAR T cells increased in the presence of APG101 (7.9 x 105 vs6.0 x 105, P = 0.01) and residual tumor cells were diminished (1.7 x 105 vs2.7 x 105, P = 0.02). Of note, APG101 itself did not affect CAR T cells or tumor cells when cultured separately. Moreover, the central memory CAR T (TCM) cell subset showed higher CD95L expression after coculturing which could be inhibited by APG101. Therefore, the addition of APG101 to the coculture resulted in a significant accumulation of TCM subset after APG101 treatment. Conclusion Upregulation of CD95L after repeated antigen stimulation was reversed by APG101. CD95L blockade enhanced CAR T cell survival and promoted killing of tumor cells in vitro. Combining CAR T cell therapy with CD95L inhibitor might improve CAR T cell persistence in vivo and thus enhance the effect of CAR T cell therapy. Disclosures Schmitt: Therakos Mallinckrodt: Other: Financial Support . Kneisel:Apogenix AG: Employment. Hoeger:Apogenix AG: Employment, Membership on an entity's Board of Directors or advisory committees. Schmitt:MSD: Membership on an entity's Board of Directors or advisory committees, Other: Sponsoring of Symposia; Therakos Mallinckrodt: Other: Financial Support.

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Mechanisms of Antigen Escape: Discovery of a Novel CD19 Point Mutation That Renders Leukemic Tumor Cells Resistant to Anti-CD19 Chimeric Antigen Receptor (CAR) T Cell Therapy

Transplantation and Cellular Therapy ◽

10.1016/s2666-6367(21)00436-x ◽

2021 ◽

Vol 27 (3) ◽

pp. S339

Author(s):

Armin Ghobadi ◽

Matthew Cooper ◽

Matthew L. Baker ◽

Christopher A. Miller ◽

Francesca Ferraro ◽

...

Keyword(s):

T Cell ◽

Cell Therapy ◽

Tumor Cells ◽

Point Mutation ◽

Chimeric Antigen Receptor ◽

Antigen Receptor ◽

T Cell Therapy ◽

Car T Cell ◽

Car T Cell Therapy ◽

Car T

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IMMU-30. DISSECTING THE DYNAMIC RESPONSES OF GLIOBLASTOMA TO CAR T CELL THERAPY USING PATIENT-DERIVED TUMOR ORGANOIDS AND SINGLE-CELL MULTI-OMICS ANALYSES

Neuro-Oncology ◽

10.1093/neuonc/noaa215.460 ◽

2020 ◽

Vol 22 (Supplement_2) ◽

pp. ii111-ii111

Author(s):

Daniel Zhang ◽

Ryan Salinas ◽

Donald O’Rourke ◽

Guo-Li Ming ◽

Hongjun Song

Keyword(s):

T Cells ◽

T Cell ◽

Tumor Microenvironment ◽

Cell Surface ◽

Cell Therapy ◽

Tumor Cells ◽

T Cell Therapy ◽

Car T Cell ◽

Car T Cell Therapy ◽

Car T

Abstract Immunotherapy, including chimeric antigen receptor (CAR) T cell therapy, has yielded major advancements for a number of hard-to-treat cancers; however, its transformative potential has yet to be realized in glioblastoma (GBM). Clinical studies of EGFRvIII targeted CAR T cell therapy have indicated that tumor heterogeneity, immune microenvironment, and adaptive responses to treatment may play important roles in limiting overall efficacy. We sought to examine comprehensively the dynamic molecular landscape of CAR T cell therapy in GBM using patient-derived GBM organoids (GBOs), a newly established laboratory model of inter- and intra- tumoral heterogeneity. Especially advantageous in these studies, GBOs preserve the intrinsic composition of somatic mutations, transcriptomic states, and non-neoplastic cells that contribute to the tumor microenvironment. Complementing the complexity of this biological system, we constructed an integrated single-cell multi-omics platform to interrogate gene expression, cell surface protein expression, somatic variants, and TCR sequences all from the same cell. Co-culture of GBOs and EGFRvIII targeted CAR T cells led to rapid T cell activation with concomitant upregulation of cytokine response gene programs in both antigen-positive and antigen-negative tumor cells. The adaptive tumor response also included expression of immune checkpoint receptor (ICR) ligands, such as PD-L1. At later time points, T cells transitioned into a dysfunctional or exhausted state, as characterized by increased cell surface expression of inhibitory receptors, such as PD-1, and decreased markers of effector activity despite the presence of antigen. Interestingly, CAR T cell therapy not only led to changes in immune-related pathways and tumor microenvironment, but it also induced shifts in tumor cell states with the depletion of an oligodendrocyte precursor cell-like state and corresponding enrichment in an astrocyte-like state. This finding suggests that EGFRvIII targeted CAR T cell therapy may leverage intrinsic cellular plasticity to induce differentiation-like effects in the surviving tumor cells.

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