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Biology subjects

Zinselmeyer, B.

Publications and source records attributed to Zinselmeyer, B..

3 recordsLinked to original sources

Immune Checkpoint Therapy Drives Maturation of a Cellular Neighborhood Nucleated by T Cell-APC Triads Enabling Spatially Compartmentalized Tumor Immunity

Spatially organized immune hubs of T cells and antigen-presenting cells (APCs) have been linked to immune checkpoint therapy (ICT) efficacy, yet the mechanisms underlying their function remain unclear. Using CODEX multiplex imaging, we longitudinally characterized the dynamic evolution of intratumoral cellular neighborhoods (CN) defined by "triad" interactions of CD4 and CD8 T cells with two distinct myeloid APC populations: cDC1s and IFN{gamma}-activated macrophages. We termed this CN the immunity-promoting CN (IP-CN) and tracked its progressive development during tumor rejection induced by -CTLA-4/-PD-1 therapy. A coordinated IFN{gamma} and TNF signaling signature accompanied the IP-CN assembly. Over time, the IP-CN underwent functional maturation, forming specialized sub-neighborhoods that compartmentalized proliferating T cells at the tumor periphery versus cytotoxic T effector cells interacting with tumor cell targets. Our findings reveal a spatiotemporal mechanism by which the IP-CN sustains and amplifies cytotoxic T cell responses, demonstrating how T cell-APC neighborhoods orchestrate tumor immunity.

immunology↗

Adipocytes are dispensable in shaping the ovarian cancer tumor microenvironment in the omentum

The omentum, a specialized adipose tissue within the peritoneum, is a primary niche for ovarian cancer (OC) dissemination during peritoneal carcinomatosis. Traditionally, omental adipocytes are thought to promote OC growth by supplying lipids, supported by evidence that global FABP4 deficiency reduces tumor progression. Here, we generated mice lacking mature adipocytes in the peritoneum, including the omentum. ID8p53-/-Brca2-/-, BPPNM, and KPCA OC cells retained a propensity to seed regions typically associated with adipocytes, even without mature adipocytes. However, the lack of mature adipocytes did not suppress peritoneal OC expansion, whereas removing the adipocyte-free omentum did. Murine and human single-cell RNA sequencing revealed that endothelial FABP4 was high in the omentum. Indeed, endothelial cell-selective deficiency of FABP4 reduced OC growth in the peritoneum. These findings prompt a reevaluation of adipocyte contributions to OC progression and suggest a key role of the omental vasculature in supporting OC metabolic growth.

cancer biology↗

Interleukin-1α and Leukemia Inhibitory Factor Promote Extramedullary Hematopoiesis

Extramedullary hematopoiesis (EMH) expands hematopoietic capacity outside of the bone marrow in response to inflammatory conditions, including infections and cancer. Because of its inducible nature, EMH offers a unique opportunity to study the interaction between hematopoietic stem and progenitor cells (HSPCs) and their niche. In cancer patients, the spleen frequently serves as an EMH organ and provides myeloid cells that may worsen pathology. Here, we examined the relationship between HSPCs and their splenic niche in EMH secondary to solid tumor. We identify an inflammatory gene signature characterized by TNF expression in HSPCs. We show a role for IL-1 in producing this gene signature and TNF expression in HSPCs in activating splenic niche activity. We also demonstrate that tumor-derived Leukemia Inhibitory Factor (LIF) induces proliferation of splenic niche cells. IL-1 and LIF display cooperative effects in activating EMH and are both upregulated in some human cancers. Together, these data expand avenues for developing niche-directed therapies and further exploring EMH accompanying inflammatory pathologies like cancer.

immunology↗