A Novel Humanized Immune Stroma PDX Model for Therapeutic Studies
Ontology highlight
ABSTRACT: Standard preclinical human tumor models lack a human tumor stroma. However, as stroma contributes to therapeutic resistance, the lack of human stroma may make current models less stringent for testing new therapies. To address this, we created a human in mouse model of cancer with a human tumor stroma. This humanized immune stroma patient derived xenograft (HIS-PDX) uses patient-derived tumor cells, cancer-associated mesenchymal stem cells and human endothelial cells transplanted into BLT (bone marrow, liver, thymus) humanized mice. The model contains human connective tissues, vascular and immune cell infiltrates. RNA sequencing analysis demonstrated a 94-96% correlation with primary human tumor. Using this model, we demonstrate the impact of human tumor stroma on response to both small molecule and immune therapies. Combined our data confirm a critical role for human stoma plays an important role in therapeutic response and that this model can be an important tool for preclinical drug testing.
Project description:Metastasized colorectal cancer (CRC) is associated with a poor prognosis and rapid disease progression. Besides hepatic metastasis, peritoneal carcinomatosis is the major cause of death in UICC stage IV CRC patients. Insights into differential site-specific reconstitution of tumor cells and the corresponding tumor microenvironment are still missing. Here, we analysed the transcriptome of single cells derived from murine multivisceral CRC and gave insight into the inter-metastatic cellular heterogeneity regarding tumor epithelium, stroma and immune cells. Interestingly, we found an intercellular site-specific network of cancer associated fibroblasts and tumor epithelium during peritoneal metastasis as well as an autologous feed-forward loop in cancer stem cells. We furthermore deciphered a metastatic dysfunctional adaptive immunity by a loss of B cell dependent antigen presentation and consecutive effector cell exhaustion. Consequently, we demonstrate the high human-mimicking potential of this murine metastatic CRC model and provide a valid tool for future site-specific preclinical drug testing.
Project description:Metastasized colorectal cancer (CRC) is associated with a poor prognosis and rapid disease progression. Besides hepatic metastasis, peritoneal carcinomatosis is the major cause of death in UICC stage IV CRC patients. Insights into differential site-specific reconstitution of tumor cells and the corresponding tumor microenvironment are still missing. Here, we analysed the transcriptome of single cells derived from murine multivisceral CRC and gave insight into the inter-metastatic cellular heterogeneity regarding tumor epithelium, stroma and immune cells. Interestingly, we found an intercellular site-specific network of cancer associated fibroblasts and tumor epithelium during peritoneal metastasis as well as an autologous feed-forward loop in cancer stem cells. We furthermore deciphered a metastatic dysfunctional adaptive immunity by a loss of B cell dependent antigen presentation and consecutive effector cell exhaustion. Consequently, we demonstrate the high human-mimicking potential of this murine metastatic CRC model and provide a valid tool for future site-specific preclinical drug testing.
Project description:We adapted a spontaneously-arising, genetically-heterogeneous, thymic transplantation-based murine model of T-ALL, recapitulating key histopathological and genetic features of the human disease, to the preclinical testing of targeted and immune-directed therapies.
Project description:We adapted a spontaneously-arising, genetically-heterogeneous, thymic transplantation-based murine model of T-ALL, recapitulating key histopathological and genetic features of the human disease, to the preclinical testing of targeted and immune-directed therapies.
Project description:Recent studies highlight the critical role of microglia in neurodegenerative disorders and emphasize the need for humanized models to accurately study microglial responses. Human-mouse microglia xenotransplantation models are a valuable platform for functional studies and for testing therapeutic approaches, yet currently those models are only available for academic research. This hampers their implementation for the development and testing of medication that targets human microglia. We developed the hCSF1Bdes mouse line, which is suitable as a new transplantation model and available to be crossed to any disease model of interest. The hCSF1Bdes model created by CRISPR gene editing is RAG2 deficient and expresses human CSF1. Additionally, we crossed this model with two humanized App KI mice, the AppHu and the AppSAA. Flow cytometry, immunohistochemistry and bulk sequencing was used to study the response of microglia in the context of Alzheimer’s disease. Our results demonstrate the successful transplantation of iPSC-derived human microglia into the brains of hCSF1Bdes mice without triggering a NK-driven immune response. Furthermore, we confirmed the multipronged response of microglia in the context of Alzheimer’s disease. The hCSF1Bdes and the crosses with the Alzheimer’s disease knock-in model AppSAA and the humanized App knock-in control mice, AppHu are deposited with EMMA and fully accessible to the research community. The hCSF1Bdes mouse is available for both non-profit and for-profit organisations, facilitating the use of the xenotransplantation paradigm for human microglia to study complex human disease.
Project description:CD200R is an immune checkpoint receptor of the IgG family that is primarily expressed on cells of the myeloid lineage. In vivo studies with knockout mice of either the receptor or its ligand, CD200, have demonstrated that it is an inhibitory receptor capable of negatively regulating immune responses. Previous work using agonistic antibodies to mouse CD200R showed inhibition of mast cell activation in multiple preclinical models of autoimmune diseases. We developed an agonistic antibody to the human CD200 receptor to downregulate the immune system human inflammatory conditions. Ucenprubart, is a humanized IgG4 monoclonal antibody that binds and agonizes human CD200R to suppress cellular activity in CD200R-expressing cells.The antibody was engineered to have desired properties for agonism and cross-reactivity to cyno CD200R. In vivo the antibody demonstrated efficacy in a humanized mouse model of contact hypersensitivity as well as passive cutaneous anaphylaxis in cynomolgus monkeys.
Project description:Tumor-associated macrophages (TAMs) represent abundantly in the tumor microenvironment (TME) and are thought to be novel targets for cancer immunotherapy. To elucidate the antitumor effects of therapeutics targeting human TAMs in vivo, we have here established a preclinical tumor xenograft model using immunodeficient mice expressing multiple human cytokines (MITRG mice) and examined the anti-tumor effect of anti–human SIRPα antibodies SE12C3, which inhibit the interaction of CD47 on tumor cells and enhance Fcγ receptor-mediated phagocytosis of tumor cells by human macrophages. Humanized immune system (HIS)–MITRG mice particularly facilitate human macrophage differentiation following transplantation of human CD34+ hematopoietic stem and progenitor cells. HIS–MITRG mice promoted the growth of both cell line– and patient–derived B cell lymphoma and infiltration of human TAMs into the tumor. Treatment of rituximab with SE12C3 markedly inhibited B–cell lymphoma growth in HIS-MITRG mice. The inhibition of B–cell lymphoma growth depended on human macrophages and was attributable to the promotion of rituximab–mediated lymphoma cell phagocytosis by human macrophages. In addition, the treatment of rituximab with SE12C3 induced reprogramming of human TAMs towards the pro-inflammatory phenotype in the TME. Furthermore, we demonstrated that the treatment of rituximab with SE12C3 significantly inhibited diffuse large B–cell lymphoma patient–derived tumor growth in HIS–MITRG mice. Together, HIS–MITRG mice provide an excellent mouse model for in vivo preclinical evaluation of the anti-tumor effect of therapeutics targeting human TAMs in the TME, such as anti–human SIRPα antibodies.