Antitumor activity of CAR-T cells targeting the intracellular oncoprotein WT1 can be enhanced by vaccination

Key Points T cells expressing a CAR consisting of scFv #213 targeting WT1 peptide/HLA-A*2402 complex killed HLA-A*2402+ WT1+ tumor cell lines. The therapeutic efficacy of #213 scFv CAR-T cells was shown to be enhanced by DC vaccine in a murine xenograft model.

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Nanobody Armed T Cells Endow CAR-T Cells the Ability to Against Lymphoma Cells

10.21203/rs.3.rs-546282/v1 ◽

2021 ◽

Author(s):

Hongxia Wang ◽

Liyan Wang ◽

Yanning Li ◽

Guangqi Li ◽

Xiaochun Zhang ◽

...

Keyword(s):

T Cells ◽

Tumor Cell ◽

Tumor Cells ◽

Cell Lines ◽

Phage Display Library ◽

Target Cells ◽

Tumor Cell Lines ◽

Car T Cells ◽

Car T

Abstract BackgroundTaking advantages of nanobody (Nb) in immunotherapy, here we investigate the cytotoxicity of Nb based Chimeric antigen receptor T cells (Nb CAR-T) against Lymphoma cells.MethodsCD19 Nb CAR-T, CD20 Nb CAR-T, and Bispecific Nb CAR-T cells were generated by panning anti-human CD19, CD20 specific nanobodies sequences from naive phage display library, then integrating Nb genes with lentiviral cassette that included other CARs elements, and finally transducing T cells that were expanded under optimization system with above prepared CARs lentiviruses. Prepared Nb CAR-T cells were co-cultured with tumor cell lines or primary tumor cells for 24 hours or 5 days to evaluate the biological function. ResultsObtained several Nb sequences specific to CD19 and CD20. Optimized culture conditions of T cells that expand 87.5 folds after 7 days of activation. Generated Nb CAR-T cells that could recognize Burkitt lymphoma cell lines (Raji and Daudi), induce activation, proliferation, and therefore kill target cells specifically. Furthermore, same results were also obtained from patient samples with cytotoxicity about 60%. ConclusionsOur study demonstrated that nanobody based single and bispecific CAR-T cells have certain killing ability against both tumor cell lines and patient-derived tumor cells in vitro.

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Expression of MyD88/CD40 Drives In Vivo Activation and Proliferation of Chimeric Antigen Receptor-Modified T Cells That Can be Effectively Regulated By Inducible Caspase-9

Blood ◽

10.1182/blood.v126.23.851.851 ◽

2015 ◽

Vol 126 (23) ◽

pp. 851-851

Author(s):

Aaron Foster ◽

Peter Chang ◽

Pei-Yi Lin ◽

Jeannette Crisostomo ◽

Aruna Mahendravada ◽

...

Keyword(s):

T Cells ◽

T Cell ◽

Tumor Cell ◽

Cell Lines ◽

Tumor Control ◽

Tumor Cell Lines ◽

Car T Cells ◽

Car T Cell ◽

Car T

Abstract Introduction: Efficacy of chimeric antigen receptor (CAR)-modified T cells is dependent on their in vivo survival and expansion following infusion. The addition of accessory molecules (e.g., costimulatory and cytokine genes) may improve CAR-T proliferation and potency, but may also increase toxicity of these next generation CAR-T cell therapies, suggesting that the incorporation of a built in "safety switch" would balance safety and efficacy in a single, controllable therapy. Here, we demonstrate that cytosolic coexpression of a MyD88/CD40-derived fusion protein dramatically enhances CAR-T activation, cytokine production, and proliferation in vivo, resulting in improved antitumor efficacy. Importantly, CAR-T cell numbers, elevated cytokine levels, and observed CAR-T-related toxicity could be controlled by titratable rimiducid administration to reduce or eliminate CAR-T cells by activating the inducible caspase-9 (iC9) suicide gene. Methods: Human T cells were activated with anti-CD3/CD28 and transduced with retrovirus encoding, iC9, a first generation CAR (with CD3ζ) targeting CD19, Her2 or PSCA, and a detached, fusion protein comprising signaling domains from MyD88 and CD40 (MC). For comparison, additional CARs were constructed without MC, with MyD88 or CD40 elements only, or with conventional CARs coexpressing CD28 within the CAR molecule (CAR.28.ζ). Transduced T cells were assessed in vitro for cytotoxicity, cytokine production and proliferation against tumor cell lines (CD19+: Daudi, Raji; Her2+: SK-BR-3; PSCA+: Capan-1, HPAC). In vivo antitumor efficacy of CAR-modified T cells was assessed using immunodeficient NSG mice engrafted with antigen-matched tumor cell lines (5x105 Raji, i.v.; 1x106 SK-BR-3, s.c; 2x106 HPAC, s.c.) followed by i.t. or i.v. injection of variable doses of T cells. Reduction or elimination of CAR-T cells was performed by i.p. injection of rimiducid (0 - 5 mg/kg). Tumor cell lines expressing luciferase or T cells co-transduced with luciferase-encoding vectors were used for bioluminescence imaging (BLI) to measure tumor growth or T cell expansion/elimination, respectively. Serum cytokine levels were assessed by blood draws and CAR-T cell frequency was measured by flow cytometry. Results: All CAR constructs were stably expressed in T cells (30-90%). CAR vectors coexpressing MC induced high IL-2 levels in vitro when exposed to target antigen+ tumor cells (CD19 = 4246 ± 52, Her2 = 2613 ± 1298, and PSCA = 3263 ± 1393 pg/ml per 1x105 T cells over 48 hrs) and corresponded to improved CAR-T cell proliferation and tumor elimination compared to control vectors. In NSG mice, MC costimulation resulted in >2,000-fold expansion of CD19-targeted CAR-T cells and complete tumor control for >100 days in 100% of mice engrafted with CD19+ Raji cells (p = 0.0002) following injection of 5x106 CAR-T cells, followed on day 7 with a single i.p. dose of rimiducid (5 mg/kg) to control toxicity. MC-enabled CAR-T cells were eliminated or partially reduced by rimiducid titrations, which corresponded to decreased cytokine (IL-6, IFN-γ, TNF-α) levels and restoration of health in animals showing signs of toxicity (e.g., ≥15% weight loss). For solid tumors, Her2-targeted, MC-enabled CAR-T cells showed a 150-fold in vivo expansion and compared favorably to first (Her2.ζ; p = 0.01) and second generation (Her2.28.ζ; p = 0.01) CARs, causing 100% elimination of SK-BR-3 tumors and enhanced survival for >60 days following i.t. injection (p = 0.0015). PSCA-targeted CARs expressing MC also drove complete and durable (>42 days) elimination of large (200 mm3) HPAC tumors in 100% of mice, after a single i.v. injection of 1x107 CAR-T cells followed on day 14 with a single 5 mg/kg i.p. rimiducid dose to reverse toxicity. Summary: Coexpression of MC, and the cell therapy safety switch "CaspaCIDe", in combination with a first generation CAR, together comprising the novel "CIDeCAR" platform technology, dramatically increases efficacy against a number of tumor targets by enhancing T cell engraftment and proliferation following infusion, while incorporating an effective, built-in safety mechanism. In three distinct tumor models, rimiducid administration promptly eliminated signs and symptoms of CAR toxicity without subsequent loss of tumor control. CIDeCAR technology may allow the development of safer and more effective CAR-T cell therapies for a range of difficult-to-treat liquid and solid tumors. Disclosures Foster: Bellicum Pharmaceuticals: Employment. Chang:Bellicum Pharmaceuticals: Employment. Lin:Bellicum Pharmaceuticals: Employment. Crisostomo:Bellicum Pharmaceuticals: Employment. Mahendravada:Bellicum Pharmaceuticals: Employment. Lu:Bellicum Pharmaceuticals: Employment. Khalil:Bellicum Pharmaceuticals: Employment. Saha:Bellicum Pharmaceuticals: Employment. Shaw:Bellicum Pharmaceuticals: Employment. Morschl:Bellicum Pharmaceuticals: Employment. Slawin:Bellicum Pharmaceuticals: Employment, Equity Ownership. Spencer:Bellicum Pharmaceuticals: Employment, Equity Ownership.

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548 Phase 2 study of FLX475 in combination with ipilimumab in advanced melanoma

Journal for ImmunoTherapy of Cancer ◽

10.1136/jitc-2021-sitc2021.548 ◽

2021 ◽

Vol 9 (Suppl 3) ◽

pp. A578-A578

Author(s):

Rakesh Goyal ◽

Nicole Nasrah ◽

Dan Johnson ◽

William Ho

Keyword(s):

Clinical Trial ◽

T Cells ◽

Antitumor Activity ◽

Regulatory T Cells ◽

Response Rate ◽

Advanced Melanoma ◽

Phase 2 ◽

Car T Cells ◽

Phase 2 Study ◽

Car T

BackgroundRegulatory T cells (Treg) can dampen antitumor immune responses in the tumor microenvironment (TME) and have been shown to correlate with poor clinical outcome. Translational studies have demonstrated an accumulation of Treg in tumors after treatment with immunotherapies including CAR-T cells and anti-CTLA-4, which could potentially reflect a mechanism of adaptive immune resistance.1–2 CCR4, the receptor for the chemokines CCL17 and CCL22, is the predominant chemokine receptor on human Treg and is responsible for the migration and accumulation of Treg in the TME. Preclinical studies with orally available CCR4 antagonists have demonstrated potent inhibition of Treg migration into tumors, an increase in the intratumoral Teff/Treg ratio, and antitumor efficacy as a single agent and in combination with checkpoint inhibitors, including anti-CTLA-4.3 In a first-in-human trial conducted in healthy volunteers, the oral CCR4 antagonist FLX475 was demonstrated to be well tolerated with outstanding pharmacokinetic and pharmacodynamic properties.4 An ongoing Phase 1/2 clinical trial of FLX475 is examining the safety and preliminary antitumor activity of FLX475 as monotherapy and in combination with pembrolizumab in subjects with several types of advanced cancer.5 Given the preclinical data demonstrating a significant enhancement of the antitumor activity of anti-CTLA-4 when combined with FLX475, a Phase 2 study investigating the combination of FLX475 and ipilimumab is now being conducted in subjects with advanced melanoma.MethodsThis clinical trial is a Phase 2, multicenter, open-label, single-arm study to determine the antitumor activity of FLX475 in combination with ipilimumab in subjects with advanced melanoma previously treated with an anti-PD-1 or anti-PD-L1 agent. The primary objectives of the study are to evaluate objective response rate, and the safety and tolerability of this combination. The study will first examine the safety of the combination of the 100 mg PO QD recommended Phase 2 dose of FLX475 and the approved 3 mg/kg IV Q3W dose of ipilimumab as part of a safety run-in phase, prior to examining the degree of antitumor activity in approximately 20 subjects. Evidence of an overall response rate (ORR) notably greater than the expected ORR of ipilimumab monotherapy alone in such subjects, which has been shown to be approximately 14%,6 would provide preliminary clinical evidence in support of the clinical hypothesis that CCR4 blockade by FLX475 can significantly enhance the antitumor activity of an anti-CTLA-4 checkpoint inhibitor.Trial RegistrationClinicalTrials.gov Identifier: NCT04894994ReferencesO’Rourke D, Nasrallah M, Desai A, Melenhorst J, Mansfield K, Morrissette J, Martinez-Lage M, Brem S, Maloney E, Shen A, Isaacs R, Mohan S, Plesa G, Lacey S, Navenot J, Zheng Z, Levine B, Okada H, June C, Brogdon J, Maus M. A single dose of peripherally infused EGFRvIII-directed CAR T cells mediates antigen loss and induces adaptive resistance in patients with recurrent glioblastoma. Sci Transl Med 2017;9:eaaa0984. doi: 10.1126/scitranslmed.aaa0984.Sharma A, Subudhi S, Blando J, Vence L, Wargo J, Allison JP, Ribas A, Sharma P. Anti-CTLA-4 immunotherapy does not deplete FOXP3+ regulatory T cells (Tregs) in human cancers-Response. Clin Cancer Res 2019;25:1233–1238.Marshall L, Marubayashi S, Jorapur A, Jacobson S, Zibinsky M, Robles O, Hu D, Jackson J, Pookot D, Sanchez J, Brovarney M, Wadsworth A, Chian D, Wustrow D, Kassner P, Cutler G, Wong B, Brockstedt D, Talay O. Tumors establish resistance to immunotherapy by regulating Treg recruitment via CCR4. J Immunother Cancer 2020;8:e000764.van Marle S, van Hoogdalem E, Johnson D, Okal A, Kassner P, Wustrow D, Ho W, Smith S. Pharmacokinetics, pharmacodynamics, and safety of FLX475, an orally-available, potent, and selective small-molecule antagonist of CCR4, in healthy volunteers. J Immunother Cancer 2018; 6(Suppl 1):P484(SITC 2018).Powderly J, Chmielowski B, Brahmer J, Piha-Paul S, Bowyer S, LoRusso P, Catenacci D, Wu C, Barve M, Chisamore M, Nasrah N, Johnson D, Ho W. Phase I/II dose-escalation and expansion study of FLX475 alone and in combination with pembrolizumab in advanced cancer. Journal of Clinical Oncology 2020;38(15_suppl): TPS3163 (ASCO 2020).Long G, Mortier L, Schachter J, Middleton M, Neyns B, Sznol M, Zhou H, Ebbinghaus S, Ibrahim N, Arance A, Ribas A, Blank C and Robert C. Society for Melanoma Research 2016 Congress. Pigment Cell & Melanoma Research 2017;30:76–156.Ethics ApprovalThis study has been approved by the Institutional Review Board at each investigational site.

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SynNotch CAR circuits enhance solid tumor recognition and promote persistent antitumor activity in mouse models

Science Translational Medicine ◽

10.1126/scitranslmed.abd8836 ◽

2021 ◽

Vol 13 (591) ◽

pp. eabd8836

Author(s):

Axel Hyrenius-Wittsten ◽

Yang Su ◽

Minhee Park ◽

Julie M. Garcia ◽

Josef Alavi ◽

...

Keyword(s):

Ovarian Cancer ◽

T Cells ◽

T Cell ◽

Antitumor Activity ◽

Solid Tumors ◽

Mouse Models ◽

Solid Tumor ◽

Car T Cells ◽

Therapeutic Benefits ◽

Car T

The first clinically approved engineered chimeric antigen receptor (CAR) T cell therapies are remarkably effective in a subset of hematological malignancies with few therapeutic options. Although these clinical successes have been exciting, CAR T cells have hit roadblocks in solid tumors that include the lack of highly tumor-specific antigens to target, opening up the possibility of life-threatening “on-target/off-tumor” toxicities, and problems with T cell entry into solid tumor and persistent activity in suppressive tumor microenvironments. Here, we improve the specificity and persistent antitumor activity of therapeutic T cells with synthetic Notch (synNotch) CAR circuits. We identify alkaline phosphatase placental-like 2 (ALPPL2) as a tumor-specific antigen expressed in a spectrum of solid tumors, including mesothelioma and ovarian cancer. ALPPL2 can act as a sole target for CAR therapy or be combined with tumor-associated antigens such as melanoma cell adhesion molecule (MCAM), mesothelin, or human epidermal growth factor receptor 2 (HER2) in synNotch CAR combinatorial antigen circuits. SynNotch CAR T cells display superior control of tumor burden when compared to T cells constitutively expressing a CAR targeting the same antigens in mouse models of human mesothelioma and ovarian cancer. This was achieved by preventing CAR-mediated tonic signaling through synNotch-controlled expression, allowing T cells to maintain a long-lived memory and non-exhausted phenotype. Collectively, we establish ALPPL2 as a clinically viable cell therapy target for multiple solid tumors and demonstrate the multifaceted therapeutic benefits of synNotch CAR T cells.

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A Preclinical Embryonic Zebrafish Xenograft Model to Investigate CAR T Cells in Vivo

Cancers ◽

10.3390/cancers12030567 ◽

2020 ◽

Vol 12 (3) ◽

pp. 567 ◽

Cited By ~ 3

Author(s):

Susana Pascoal ◽

Benjamin Salzer ◽

Eva Scheuringer ◽

Andrea Wenninger-Weinzierl ◽

Caterina Sturtzel ◽

...

Keyword(s):

T Cells ◽

T Cell ◽

Cellular Therapy ◽

Xenograft Model ◽

Model Systems ◽

Preclinical Model ◽

Car T Cells ◽

Car T Cell ◽

Car T

Chimeric antigen receptor (CAR) T cells have proven to be a powerful cellular therapy for B cell malignancies. Massive efforts are now being undertaken to reproduce the high efficacy of CAR T cells in the treatment of other malignancies. Here, predictive preclinical model systems are important, and the current gold standard for preclinical evaluation of CAR T cells are mouse xenografts. However, mouse xenograft assays are expensive and slow. Therefore, an additional vertebrate in vivo assay would be beneficial to bridge the gap from in vitro to mouse xenografts. Here, we present a novel assay based on embryonic zebrafish xenografts to investigate CAR T cell-mediated killing of human cancer cells. Using a CD19-specific CAR and Nalm-6 leukemia cells, we show that live observation of killing of Nalm-6 cells by CAR T cells is possible in zebrafish embryos. Furthermore, we applied Fiji macros enabling automated quantification of Nalm-6 cells and CAR T cells over time. In conclusion, we provide a proof-of-principle study that embryonic zebrafish xenografts can be used to investigate CAR T cell-mediated killing of tumor cells. This assay is cost-effective, fast, and offers live imaging possibilities to directly investigate CAR T cell migration, engagement, and killing of effector cells.

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Photothermal Therapy Promotes Tumor Infiltration and Antitumor Activity of CAR T Cells

Advanced Materials ◽

10.1002/adma.201900192 ◽

2019 ◽

Vol 31 (23) ◽

pp. 1900192 ◽

Cited By ~ 71

Author(s):

Qian Chen ◽

Quanyin Hu ◽

Elena Dukhovlinova ◽

Guojun Chen ◽

Sarah Ahn ◽

...

Keyword(s):

T Cells ◽

Antitumor Activity ◽

Photothermal Therapy ◽

Tumor Infiltration ◽

Car T Cells ◽

Car T

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CD19-CAR-T Cells Bearing a KIR/PD-1-Based Inhibitory CAR Eradicate CD19+HLA-C1− Malignant B Cells While Sparing CD19+HLA-C1+ Healthy B Cells

Cancers ◽

10.3390/cancers12092612 ◽

2020 ◽

Vol 12 (9) ◽

pp. 2612

Author(s):

Lei Tao ◽

Muhammad Asad Farooq ◽

Yaoxin Gao ◽

Li Zhang ◽

Congyi Niu ◽

...

Keyword(s):

T Cells ◽

B Cells ◽

B Cell ◽

Killer Cell ◽

Xenograft Model ◽

Sustained Remission ◽

T Cell Therapy ◽

Car T Cells ◽

Car T

B cell aplasia caused by “on-target off-tumor” toxicity is one of the clinical side effects during CD19-targeted chimeric antigen receptor (CAR) T (CD19-CAR-T) cells treatment for B cell malignancies. Persistent B cell aplasia was observed in all patients with sustained remission, which increased the patients’ risk of infection. Some patients even died due to infection. To overcome this challenge, the concept of incorporating an inhibitory CAR (iCAR) into CAR-T cells was introduced to constrain the T cells response once an “on-target off-tumor” event occurred. In this study, we engineered a novel KIR/PD-1-based inhibitory CAR (iKP CAR) by fusing the extracellular domain of killer cell immunoglobulin-like receptors (KIR) 2DL2 (KIR2DL2) and the intracellular domain of PD-1. We also confirmed that iKP CAR could inhibit the CD19 CAR activation signal via the PD-1 domain and CD19-CAR-T cells bearing an iKP CAR (iKP-19-CAR-T) exerted robust cytotoxicity in vitro and antitumor activity in the xenograft model of CD19+HLA-C1− Burkitt’s lymphoma parallel to CD19-CAR-T cells, whilst sparing CD19+HLA-C1+ healthy human B cells both in vitro and in the xenograft model. Meanwhile, iKP-19-CAR-T cells exhibited more naïve, less exhausted phenotypes and preserved a higher proportion of central memory T cells (TCM). Our data demonstrates that the KIR/PD-1-based inhibitory CAR can be a promising strategy for preventing B cell aplasia induced by CD19-CAR-T cell therapy.

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Photothermal Therapy: Photothermal Therapy Promotes Tumor Infiltration and Antitumor Activity of CAR T Cells (Adv. Mater. 23/2019)

Advanced Materials ◽

10.1002/adma.201970166 ◽

2019 ◽

Vol 31 (23) ◽

pp. 1970166 ◽

Cited By ~ 6

Author(s):

Qian Chen ◽

Quanyin Hu ◽

Elena Dukhovlinova ◽

Guojun Chen ◽

Sarah Ahn ◽

...

Keyword(s):

T Cells ◽

Antitumor Activity ◽

Photothermal Therapy ◽

Tumor Infiltration ◽

Car T Cells ◽

Car T

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Enhanced CAR-T activity against established tumors by polarizing human T cells to secrete interleukin-9

Nature Communications ◽

10.1038/s41467-020-19672-2 ◽

2020 ◽

Vol 11 (1) ◽

Author(s):

Lintao Liu ◽

Enguang Bi ◽

Xingzhe Ma ◽

Wei Xiong ◽

Jianfei Qian ◽

...

Keyword(s):

T Cells ◽

T Cell ◽

Antitumor Activity ◽

Effector Memory ◽

T Cell Therapy ◽

Car T Cells ◽

Car T Cell ◽

Car T ◽

Ifn Γ

AbstractCAR-T cell therapy is effective for hematologic malignancies. However, considerable numbers of patients relapse after the treatment, partially due to poor expansion and limited persistence of CAR-T cells in vivo. Here, we demonstrate that human CAR-T cells polarized and expanded under a Th9-culture condition (T9 CAR-T) have an enhanced antitumor activity against established tumors. Compared to IL2-polarized (T1) cells, T9 CAR-T cells secrete IL9 but little IFN-γ, express central memory phenotype and lower levels of exhaustion markers, and display robust proliferative capacity. Consequently, T9 CAR-T cells mediate a greater antitumor activity than T1 CAR-T cells against established hematologic and solid tumors in vivo. After transfer, T9 CAR-T cells migrate effectively to tumors, differentiate to IFN-γ and granzyme-B secreting effector memory T cells but remain as long-lived and hyperproliferative T cells. Our findings are important for the improvement of CAR-T cell-based immunotherapy for human cancers.

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