Project description:Chimeric antigen receptor (CAR) and T-cell receptor (TCR) T-cell therapies are effective in a subset of patients with solid tumors, but new approaches are needed to enhance efficacy and universally improve patient outcomes. IL-15 and IL-21 are common cytokine-receptor gamma chain family members with distinct, pleiotropic effects on T-cells and other lymphocytes. We found that self-delivery of these cytokines by CAR or TCR T-cells prevents functional exhaustion by repeated stimulation and limits the emergence of dysfunctional natural killer (NK)-like T-cells. Across different preclinical murine solid tumor models, we observe enhanced regression with each individual cytokine but the greatest anti-tumor efficacy when T-cells are armored with both. Thus, the co-expression of membrane-tethered IL-15 and IL-21 represents a technology to enhance the resilience and function of engineered T-cells against solid tumors and could be applicable to multiple therapy platforms and diseases.
Project description:Chimeric antigen receptor (CAR)-T cell therapies have shown great success in treating hematologic malignancies. Nonetheless, their therapeutic effect on solid tumors remains to be improved. Recently, macrophages have attracted great attention, given their ability to infiltrate solid tumors, phagocytize tumor cells as well as their immunomodulatory capacities. The first generation of CD3ζ-based CAR-macrophages demonstrated that the CAR could stimulate macrophage phagocytosis in a tumor antigen-dependent way. Here, we genetically engineered induced pluripotent stem cell (iPSC)-derived macrophages (iMACs) with TLR4 intracellular TIR domain-containing CARs against EGFRvIII and GPC3, which yielded markedly enhanced antitumor effect in two different solid tumor models including glioblastoma, and hepatocellular carcinoma in which complete remission was achieved with CAR-iMACs alone or in combination with CD47 antibody. Moreover, the tandem CD3ζ-TIR-CAR, or the “second-generation” design of TIR-based dual signaling CAR, endowed iMACs with both target engulfment/efferocytosis capacity against antigen-expressing solid tumor cells, and potency of antigen-dependent M1 state polarization and M2 state resistance in an NF-κB dependent manner. We also illustrated a surprising mechanism of tumor cell elimination by CAR-induced efferocytosis against tumor cell apoptotic bodies. Taken together, we established the next generation CAR-iMACs equipped with orthogonal phagocytosis and polarization capacity for better antitumor functions in treating solid tumors.
Project description:We previously developed human CAR macrophages (CAR-M) and demonstrated redirection of macrophage anti-tumor function leading to tumor control in immunodeficient xenograft models. Here, we developed clinically relevant fully immunocompetent syngeneic models to evaluate the potential for CAR-M to remodel the tumor microenvironment (TME), induce T cell anti-tumor immunity, and sensitize solid tumors to PD1/PDL1 checkpoint inhibition. In vivo, anti-HER2 CAR-M significantly reduced tumor burden, prolonged survival, remodeled the TME, increased intratumoral T cell and natural killer (NK) cell infiltration, and induced epitope spreading. CAR-M therapy protected against antigen-negative relapse in a T cell dependent fashion, confirming long-term anti-tumor immunity. In HER2+ solid tumors resistant to anti-PD1(aPD1) monotherapy, the combination of CAR-M and aPD1 significantly improved tumor growth control, survival, and remodeling of the TME. These results demonstrate synergy between CAR-M and T cell checkpoint blockade and provide a strategy to enhance response to aPD1 therapy for patients with non-responsive tumors.
Project description:Vδ1T cells, a rare subset of γδT cells, hold promise for treating solid tumors. Unlike conventional T cells, they recognize tumor antigens independently of the MHC antigen-presentation pathway, making them a potential “off-the-shelf” cell therapy product. However, isolation and activation of Vδ1T cells is challenging, which has limited their clinical investigation. Here, we developed a large-scale clinical-grade manufacturing process for Vδ1T cells and validated the therapeutic potential of B7-H3-CAR-modified Vδ1T cells in treating solid tumors. Co-expression of interleukin-2 with the B7-H3-CAR led to durable anti-tumor activity of Vδ1T cells in vitro and in vivo. In multiple subcutaneous and orthotopic mouse xenograft tumor models, a single intravenous administration of the CAR-Vδ1T cells resulted in complete tumor regression. These modified cells demonstrated significant in vivo expansion and robust homing ability to tumors, akin to natural tissue-resident immune cells.Additionally, the B7-H3-CAR-Vδ1T cells exhibited a favorable safety profile. In conclusion, B7-H3-CAR-modified Vδ1T cells represent a promising strategy for treating solid tumors.
Project description:Chimeric antigen receptor T (CAR-T) cell therapies for B cell malignancies demonstrate high response rate and durable disease control. However, in the case of solid tumors, CAR-T cells have shown dysfunction ascribed to some intrinsic defects in CAR signaling. Here, we construct a multi-chain chimeric receptor, termed as Synthetic T Cell Receptor and Antigen Receptor (STAR), which incorporates antigen-recognition domain of antibody and engages entire CD3 signaling machinery of T cell receptor (TCR). In multiple solid tumor models, STAR-T cells prominently outperform CAR-T cells without notable toxicity. STAR triggers strong and sensitive TCR-like signaling upon antigen stimulation. We compared the transcriptional profiles of STAR/CAR/TCR-T cells after stimulation for different time points (0, 6, 24, 72 hours), in order to figure out whether signaling difference of these receptors led to distinct gene expression. Our results showd that STAR activation phencopied TCR, while CAR drove a different program, displayed as various pathways related to effector function, cytokine response and cell survival were altered.
Project description:The efficacy of Chimeric Antigen Receptor (CAR) T cells against solid tumors is limited by immunosuppressive factors in the tumor microenvironment (TME) including adenosine, which suppresses CAR T cells through activation of the A2A receptor (A2AR). To overcome this, CAR T cells were engineered to express A1 receptor (A1R), a receptor that signals inversely to A2AR. Using murine and human CAR T cells, constitutive A1R overexpression was demonstrated to significantly enhance CAR T cell effector function albeit at the expense of CAR T cell persistence. Through a novel CRISPR/Cas9 “knock-in” approach we demonstrated that CAR T cells engineered to express A1R in a tumor-localized manner, led to enhanced anti-tumor efficacy dependent on the transcription factor IRF8 and was transcriptionally unique when compared to A2AR deletion. This data provides a novel approach for enhancing CAR T cell efficacy in solid tumors and provides proof of principle for site-directed expression of factors that promote effector T cell differentiation.
Project description:The efficacy of Chimeric Antigen Receptor (CAR) T cells against solid tumors is limited by immunosuppressive factors in the tumor microenvironment (TME) including adenosine, which suppresses CAR T cells through activation of the A2A receptor (A2AR). To overcome this, CAR T cells were engineered to express A1 receptor (A1R), a receptor that signals inversely to A2AR. Using murine and human CAR T cells, constitutive A1R overexpression was demonstrated to significantly enhance CAR T cell effector function albeit at the expense of CAR T cell persistence. Through a novel CRISPR/Cas9 “knock-in” approach we demonstrated that CAR T cells engineered to express A1R in a tumor-localized manner, led to enhanced anti-tumor efficacy dependent on the transcription factor IRF8 and was transcriptionally unique when compared to A2AR deletion. This data provides a novel approach for enhancing CAR T cell efficacy in solid tumors and provides proof of principle for site-directed expression of factors that promote effector T cell differentiation.
Project description:The efficacy of Chimeric Antigen Receptor (CAR) T cells against solid tumors is limited by immunosuppressive factors in the tumor microenvironment (TME) including adenosine, which suppresses CAR T cells through activation of the A2A receptor (A2AR). To overcome this, CAR T cells were engineered to express A1 receptor (A1R), a receptor that signals inversely to A2AR. Using murine and human CAR T cells, constitutive A1R overexpression was demonstrated to significantly enhance CAR T cell effector function albeit at the expense of CAR T cell persistence. Through a novel CRISPR/Cas9 “knock-in” approach we demonstrated that CAR T cells engineered to express A1R in a tumor-localized manner, led to enhanced anti-tumor efficacy dependent on the transcription factor IRF8 and was transcriptionally unique when compared to A2AR deletion. This data provides a novel approach for enhancing CAR T cell efficacy in solid tumors and provides proof of principle for site-directed expression of factors that promote effector T cell differentiation.
Project description:The efficacy of Chimeric Antigen Receptor (CAR) T cells against solid tumors is limited by immunosuppressive factors in the tumor microenvironment (TME) including adenosine, which suppresses CAR T cells through activation of the A2A receptor (A2AR). To overcome this, CAR T cells were engineered to express A1 receptor (A1R), a receptor that signals inversely to A2AR. Using murine and human CAR T cells, constitutive A1R overexpression was demonstrated to significantly enhance CAR T cell effector function albeit at the expense of CAR T cell persistence. Through a novel CRISPR/Cas9 “knock-in” approach we demonstrated that CAR T cells engineered to express A1R in a tumor-localized manner, led to enhanced anti-tumor efficacy dependent on the transcription factor IRF8 and was transcriptionally unique when compared to A2AR deletion. This data provides a novel approach for enhancing CAR T cell efficacy in solid tumors and provides proof of principle for site-directed expression of factors that promote effector T cell differentiation.