Project description:Immune checkpoint inhibition treatment using aPD-1 monoclonal antibodies is a promising cancer immunotherapy approach. However, its effect on tumor immunity is narrow, as most patients do not respond to the treatment or suffer from recurrence. We show that the crosstalk between conventional type I dendritic cells (cDC1) and T cells is essential for an effective aPD-1-mediated anti-tumor response. Accordingly, we developed a Bispecific DC-T Cell Engager (BiCE), a reagent that facilitates physical interactions between PD-1+ T-cells and cDC1. BiCE treatment promoted the formation of active dendritic/T cell crosstalk in the tumor and tumor-draining lymph nodes. In vivo, single cell and physical interacting cell analysis demonstrated the distinct and superior immune reprogramming of the tumors and tumor-draining lymph nodes treated with BiCE, as compared to conventional aPD-1 treatment. BiCE introduces a new concept in immunotherapy, bridging of immune cells to potentiate cell circuits and communication pathways needed for effective anti-tumor immunity.
Project description:Therapeutic use of agonistic anti-CD40 antibodies is a potentially powerful approach for activating the immune response to eradicate tumors. However, the translation of this approach to clinical practice has been significantly restricted due to the severe dose-limiting toxicities observed in multiple clinical trials. Here, we demonstrate that conventional type-1 dendritic cells are essential for triggering antitumor immunity but not toxicity by CD40 agonists, while macrophages, platelets, and monocytes lead to the toxic events. Therefore, we designed bispecific antibodies that target CD40 activation preferentially to dendritic cells. These bispecific reagents demonstrate a superior safety profile compared to their parental CD40 monospecific antibody, while triggering potent anti-tumor activity. We suggest such cell-selective bispecific agonistic antibodies as a drug platform to bypass the dose-limiting toxicities of anti-CD40, and of additional types of agonistic antibodies used for cancer immunotherapy.
Project description:To date, bispecific antibodies designed to engage T cells have failed to show sustained responses in relapsed/refractory acute myeloid leukemia (R/R AML). Bispecific antibodies, including bispecific T-cell-engager (BiTE) molecules, predominantly recruit T cells from the local immune microenvironment. Because they are mainly applied in the R/R setting, understanding the fitness of T cells from bone marrow in AML progression, is fundamental for advancing this platform. Here, by flow cytometry analysis of bone marrow-derived T cells, we identified distinct differentiation stages and expression of inhibitory receptors at initial diagnosis (ID) and relapse (RL). Longitudinal transcriptional analyses of paired ID and RL T cells showed a senescent phenotype at ID, whereas an exhausted and memory phenotype was dominant at RL. In line with these observations, T cells at RL exhibited higher BiTE-mediated cytotoxicity than ID T cells. Finally, we provide evidence that T cells, both from ID and RL, exhibit limited functional capacity following continuous BiTE exposure compared to T cells from complete remission. Our study provides insights into the different stages of T-cell phenotype and function during AML evolution. Correlative biomarker studies in patients treated with T-cell-based immunotherapies are needed, to better understand resistance mechanisms and to advance the platform.
Project description:To date, bispecific antibodies designed to engage T cells have failed to show sustained responses in relapsed/refractory acute myeloid leukemia (R/R AML). Bispecific antibodies, including bispecific T-cell-engager (BiTE) molecules, predominantly recruit T cells from the local immune microenvironment. Because they are mainly applied in the R/R setting, understanding the fitness of T cells from bone marrow in AML progression, is fundamental for advancing this platform. Here, by flow cytometry analysis of bone marrow-derived T cells, we identified distinct differentiation stages and expression of inhibitory receptors at initial diagnosis (ID) and relapse (RL). Longitudinal transcriptional analyses of paired ID and RL T cells showed a senescent phenotype at ID, whereas an exhausted and memory phenotype was dominant at RL. In line with these observations, T cells at RL exhibited higher BiTE-mediated cytotoxicity than ID T cells. Finally, we provide evidence that T cells, both from ID and RL, exhibit limited functional capacity following continuous BiTE exposure compared to T cells from complete remission. Our study provides insights into the different stages of T-cell phenotype and function during AML evolution. Correlative biomarker studies in patients treated with T-cell-based immunotherapies are needed, to better understand resistance mechanisms and to advance the platform.
Project description:A novel affinity-tuned dual-checkpoint bispecific antibody with potent PD-L1 and moderate CD47 affinity was designed to improve the selectivity to TME and thus enhance antitumor immunity and efficacy. The gene expression analysis using Nanostring platform was performed to examine the immune cell modulation in TME following the CD47/PD-L1 bispecific treatment.
Project description:A novel affinity-tuned dual-checkpoint bispecific antibody with potent PD-L1 and moderate CD47 affinity was designed to improve the selectivity to TME and thus enhance antitumor immunity and efficacy. The scRNAseq analysis was performed to examine the immune cell modulation in TME following the CD47/PD-L1 bispecific treatment.
Project description:We report here the design of new antibody-based natural killer cell engager therapeutics (ANKET), single tetraspecific molecules engaging the NK cell activating receptors NKp46 and CD16, the β chain of the interleukin-2 receptor (IL-2R) and a tumor-associated antigen (TAA).
Project description:Bispecific T-cell engager (BiTE)-based cancer therapies that activate the cytotoxic T cells of a patient’s own immune system have gained momentum with the recent FDA approval of Blinatumomab for treating B cell malignancies. However, this approach has had limited success in targeting solid tumors. We have reported the development of BiTE-sialidase fusion proteins that enhance tumor cell susceptibility to BiTE-mediated cytolysis by T cells via targeted desialylation at the BiTE-induced T cell-tumor cell interface. Targeted desialylation results in better immunological synapse formation, T-cell activation and effector function. As a result, BiTE-sialidase fusion proteins show remarkably increased efficacy in inducing T-cell-dependent tumor cell cytolysis in response to target antigens compared to the parent BiTE molecules alone. This enhanced function is seen both in vitro and in in vivo xenograft and syngeneic solid tumor mouse models. Our findings highlight BiTE-sialidase fusion proteins as promising candidates for the development of next-generation bispecific T-cell engaging molecules for cancer immunotherapy. This transcriptomic dataset documents the effect of BiTE-sialidase vs uncojugated BiTE on T cells including the upregulation of effector associated genes.