Technology
CAR-T cell therapy
Autologous CAR-T cell therapy
Hybrid CAR
New Adoptive T Cell Transfer Approach
Chimeric Antigen Receptor (CAR) T cells use antibodies to recognize antigen proteins on the cancer and oftenly normal cell surface. Inside T cell there is a molecule called intracellular signaling domain, enhancing its activity.
Approved CAR-T cells` breakthrough efficacy against hematological B cell tumors is accompanied with high on-target/ off-tumor toxicity because target antigens are expressed on both cancer and normal B cells. Basically, current CAR-T cells indiscriminately attack cancer and normal B cells marked by targeted antigen.
TCR-T cell receptors recognize cancer-specific antigen derived peptides expressed in complex with HLA on cancer cell surface and attack them. Initially naive cancer-specific receptors were transferred to T cells with some modest results. Nowadays cancer-specific receptors with enhanced affinity are mostly used in TCR-T cells clinical studies. So TCR-T cell approach is more cancer-specific, but yet to demonstrate comparable results for solid tumors.
Our exceedingly powerful and precise Hybrid CAR-T cell therapy combines CAR-T cell power with TCR-T cell precision.
Adapted from Cell Immunotherapy (Layout), by BioRender.com (2022). Retrieved from https://app.biorender.com/biorender-templates
Problem and solution
Currently several effective CAR-T cells have been approved for hematological tumors. However, none of CAR-T cells have proven to be sufficiently effective against solid tumors, including ones in the development stage. It is because of the low receptor specificity and declining activity of T cells in immunosuppressive tumor microenvironment.
Affinity enhanced TCR approach is widely used against solid tumors, though it is limited only to modification of the receptor outside the cell without modifying the inner cell.
So we designed next generation Hybrid CAR-T cell with uniquely cancer-specific CAR and novel intracellular signaling domain for strong and persistent anti-tumor activity. Our approach demonstrates promising results in preclinical studies and is being clinically tested now.
Adapted from Cell Immunotherapy (Layout), by BioRender.com (2022). Retrieved from https://app.biorender.com/biorender-templates
Hybrid CAR-T Cell Features
Original Hybrid CAR Targeting Intracellular Antigen Peptides
We apply TCR like gene transfer technology to enhance the recognition of intracellular cancer-specific antigen molecules expressed on the cancer cell surface in HLA/MHC areas.
Our partner laboratory in Mie University discovered an antibody and designed a CAR with enhanced antigen specificity of the scFv (anti-pMHC) part to recognize the complex (pMHC) of HLA-A*0201 and MAGA-A4 antigen derived peptide, frequently expressed on solid cancer cells.
Similarly, for the PRAME antigen, we increased the HLA-A*2402 complex (pMHC) antigen specificity. As a result, it exhibits a high specificity for solid cancer intracellular antigen, and is expected to increase the therapeutic effect.
Adapted from Cell Immunotherapy (Layout), by BioRender.com (2022). Retrieved from https://app.biorender.com/biorender-templates
Discovery of GITR co-stimulation signal molecule improving cell activity
The first-generation CAR structure consists of a single-chain antibody (scFv) that recognizes the surface antigens of tumor cells, a transmembrane domain, and an intracellular domain of the TCR complex that activates T cells.
In the second generation, the intracellular domain of the T cell co-stimulator molecule was added to enhance T cell activation.
The third generation linked the intracellular domain derived from the tumor necrosis factor receptor.
Consequently CARs targeting various tumor antigens have been researched and developed. However, the co-stimulation signal molecules used as the intracellular domain in CAR are limited, and rare ones have cytotoxic activity and effective co-stimulation signal.
T Cell Nouveau CAR-T has the intracellular domain of glucocorticoid-induced tumor necrosis factor receptor (GITR), which is one of the costimulatory signal molecules with high cytotoxic activity against targeted cancer cells.
T cells proliferation rate increased by including GITR intracellular domain. In addition, inhibition of regulatory T cells immunosupressive function helps maintain persistent in vivo anti-tumor activity, resistance to the tumor microenvironment immunosuppression, resulting in excellent tumor growth-suppressing action.
Automatic Cell Processing
Automatic cell manufacturing and benefits
T Cell Nouveau commits to delivering Hybrid CAR-T cells to medical institutions faster at reduced manufacturing costs. To achieve this, we are developing an automatic cell processing All-In-One Cell Processing Unit (CPU).
Standard equipment is used for the automatic cell processing, enabling a simple design at smaller space with fewer manpower operation, eventually, shortening the manufacturing time and reducing costs.
Benefits of automation
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Quick delivery time
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High reproducibility and low cost
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Easy technology transfer and scale up
Novel CAR-T cells with novel signaling domain
GITRL secreting co-stimulatory signal molecules
to enhance therapeutic effects
In order to further enhance the effects of the GITR intracellular domain, we created a new GITR Ligand-releasing CAR-T. Along with the release of GITRL due to stimulation of CAR, it not only promotes its own activation via GITR receptor (autocrine), but also activates surrounding immune cells due to paracrine effects.
This time, we applied this new domain to the design of GD2 CAR-T, which uses our proprietary GD2 antibody as the receptor. GD2 is a glycolipid mainly expressed on the surface of nerve cells, and overexpression has been confirmed in neuroblastoma, a type of childhood cancer, triple-negative breast cancer, melanoma, etc. Additionally, our antibody portion specifically recognizes GD2 and has been confirmed to have low reactivity to related glycosphingolipids.
Adapted from Cell Immunotherapy (Layout), by BioRender.com (2022). Retrieved from https://app.biorender.com/biorender-templates
Publications
Ishihara M, Kitano S, Kageyama S, et al. NY-ESO-1- specific redirected T cells with endogenous TCR knockdown mediate tumor response and cytokine release syndrome. J. Immunother. Cancer. 2022;10:e003811. doi:10.1136/jitc-2021-003811
Sandra P. D’Angelo, MD, et al.Identification of Response Stratification Factors from Pooled Efficacy Analyses of Afamitresgene Autoleucel (“Afami-cel” [Formerly ADP-A2M4]) in Metastatic Synovial Sarcoma and Myxoid/Round Cell Liposarcoma Phase 1 and Phase 2 Trials. J. Clin. Oncol. 2022 40:16_suppl, 11562-11562
Shafer P, Kelly LM and Hoyos V (2022) Cancer Therapy With TCR-Engineered T Cells: Current Strategies, Challenges, and Prospects. Front. Immunol. 13:835762. doi: 10.3389/fimmu.2022.83576
Kageyama S, Ikeda H, Miyahara Y, Imai N, Ishihara M, Saito K, et al. Adoptive Transfer of MAGE-A4 T-Cell Receptor Gene-Transduced Lymphocytes in Patients With Recurrent Esophageal Cancer. Clin Cancer Res (2015) 21:2268–77. doi: 10.1158/1078-0432.CCR-14-1559
Hiroyoshi Hattori, et al. A Novel Affinity-Enhanced NY-ESO-1-Targeting TCR-Redirected T cell Transfer Exhibiting Early-Onset Cytokine Release Syndrome and Subsequent Tumour Responses in Synovial Sarcoma Patients. EMJ Oncol.. 2019;7[1]:38-40. Abstract No AR01.
Akahori Y, Wang L, Yoneyama M, Seo N, Okumura S, Miyahara Y, Amaishi Y, Okamoto S, Mineno J, Ikeda H, Maki T, Fujiwara H, Akatsuka Y, Kato T, Shiku H. Antitumor activity of CAR-T cells targeting the intracellular oncoprotein WT1 can be enhanced by vaccination. Blood. 2018 Sep 13;132(11):1134-1145. doi: .1182/blood-2017-08-802926. Epub 2018 Jul 25. PMID: 30045840 Free PMC Article
Mitsui J, Nishikawa H, Muraoka D, Wang L, Noguchi T, Sato E, Kondo S, Allison JP, Sakaguchi S, Old LJ, Kato T, Shiku H. Two distinct mechanisms of augmented antitumor activity by modulation of immunostimulatory/inhibitory signals. Clin Cancer Res. 2010 May 15;16(10):2781-91. doi: 10.1158/1078-0432.CCR-09-3243. Epub 2010 May 11. PMID: 20460483.
Imai N, Ikeda H, Tawara I, Wang L, Wang L, Nishikawa H, Kato T, Shiku H. Glucocorticoid-induced tumor necrosis factor receptor stimulation enhances the multifunctionality of adoptively transferred tumor antigen-specific CD8+ T cells with tumor regression. Cancer Sci. 2009 Jul;100(7):1317-25. Doi: 10.1111/j.1349-7006.2009.01179.x. Epub 2009 Apr 29. PMID: 19432889.
Nishikawa H, Kato T, Hirayama M, Orito Y, Sato E, Harada N, Gnjatic S, Old LJ, Shiku H. Regulatory T cell-resistant CD8+ T cells induced by glucocorticoid-induced tumor necrosis factor receptor signaling. Cancer Res. 2008 Jul 15;68(14):5948-54. doi: 10.1158/0008-5472.CAN-07-5839. PMID: 18632650.