Biology subjects

Virumbrales-Munoz, M.

Publications and source records attributed to Virumbrales-Munoz, M..

4 recordsLinked to original sources

bioRxiv2026

Serial intravascular labeling resolves dynamic decidual NK residency and gestational remodeling toward T-bet-Low states

Decidual natural killer (dNK) cells are the predominant immune population at the maternal-fetal interface during early pregnancy. However, how vascular trafficking, tissue residency, proliferation, and apoptosis-associated activity are coordinated to establish and maintain the dNK population throughout pregnancy remains unclear. We hypothesized that gestational remodeling of the dNK compartment reflects coordinated changes in these cellular processes in association with progressive T-bet downregulation. We combined serial intravascular labeling (SIVL), flow cytometry, BrdU incorporation, active caspase-3 detection, spatial imaging, and Tbx21 fate mapping to examine NK cells in virgin mice and across gestation. Pregnancy altered CD49a/CD49b-defined dNK-cell composition and redistributed dNK cells among SIVL-defined vascular-accessibility states, supporting a model of dynamic dNK-cell tissue residency. Trafficking-associated marker scores displayed continuous gradients of tissue retention, circulatory/egress potential, and chemokine responsiveness rather than defining a single resident state. Spatial imaging demonstrated greater dNK-cell density in the mesometrial decidua and preferential CD31 vessel contact by recently intravascular dNK cells during early and mid-gestation. BrdU incorporation and active caspase-3 positivity peaked during early pregnancy and varied across SIVL-defined states. Tbx21 fate mapping identified a progressive and selective shift from current T-bet expression toward ex-T-bet and non-fate-mapped Eomes dNK states. T-bet-low states preferentially maintained proliferation at mid-gestation, whereas current T-bet expression was associated with greater circulatory/egress potential. However, active caspase-3 was not selectively increased in current T-bet-expressing cells. Collectively, these findings identify pregnancy-induced dNK-cell remodeling as a coordinated process integrating dynamic tissue residency, vascular accessibility, local proliferation, and apoptosis-associated activity, alongside a progressive shift toward T-bet-low dNK states.

immunology↗

bioRxiv2026

Modeling the metabolic heterogeneity of high-grade serous ovarian cancer solid tumors in 3D Microphysiological systems

High-grade serous carcinoma (HGSOC) is the deadliest subtype of ovarian cancer, characterized by high metastatic rates. HGSOC is typically diagnosed at late stages, and treatment options are limited, resulting in a 60% recurrence rate. HGSOC cells exhibit metabolic plasticity, dynamically shifting between glycolysis and oxidative phosphorylation (OXPHOS) to meet energy demands for tumor progression. To evaluate therapeutic strategies that target metabolic vulnerabilities, we developed a microphysiological system (MPS) that recapitulates the heterogenous cell states and bioenergetic distribution of HGSOC solid tumors. Our platform utilized HGSOC spheroids embedded in a collagen hydrogel that mimics the extracellular matrix to capture tumor progression in the ovary. We used atovaquone (ATO), an FDA-approved OXPHOS inhibitor, to prototype the capabilities of our platform to investigate metabolic plasticity in HGSOC. Treatment with ATO decreased viability and invasion of HGSOC spheroids. Crucially, ATO exhibited no cytotoxicity toward biomimetic blood vessels, preserving their integrity and permeability. Metabolic imaging revealed that ATO induces an oxidative state in the outer region of the spheroids. At the invasive front, ATO disrupted mitochondrial organization, forcing collective cell migration and eventually inducing breakdown of mitochondrial networks. Furthermore, ATO decreased YAP/TAZ pathway activity in the outer region of the spheroid, providing a potential mechanism for hindered cell invasion. Collectively, our data demonstrates that a low-potency OXPHOS inhibitor like ATO can effectively target metabolic plasticity to suppress HGSOC spheroid progression. Overall, this platform successfully recapitulated metabolic heterogeneity and provided a workflow for safely testing other drugs that target cancer metabolism.

cancer biology↗

bioRxiv2025

Exosomes are specialized vehicles to induce fibronectin assembly

Fibronectin is a key stromal matrix molecule whose assembly into fibrils is thought to require cells. In contrast, we find that small exosome-type extracellular vesicles (EVs) are critical initiators of fibronectin assembly. Fibroblasts engineered to be deficient in exosome secretion showed greatly reduced assembly of fibronectin and other stromal matrix molecules in 2D, 3D, and in vivo environments, and led to reduced tumor growth and lung metastasis by breast cancer cells. Furthermore, transgenic mice with defects in exosome secretion had greatly reduced lung fibrosis after treatment with bleomycin. In a direct test of exosome function, we find that the addition of purified small EVs to purified soluble fibronectin in a cell-free system is sufficient to induce fibronectin assembly. The EV-induced fibronectin assembly requires the presence of fibronectin-binding integrins and Syndecan-1 in the EVs. We propose a new model in which secreted exosomes directly drive stromal matrix assembly and tissue fibrosis.

cell biology↗

bioRxiv2023

Immune Cells and Inflammatory mediators cause endothelial dysfunction in a vascular microphysiological system

Functional assessment of endothelium serves as an important indicator of vascular health and is compromised in vascular disorders including hypertension, atherosclerosis, and preeclampsia. Endothelial dysfunction in these cases is linked to dysregulation of the immune system involving both changes to immune cells and increased secretion of inflammatory cytokines. Herein, we utilize a well-established microfluidic device to generate a 3-dimensional vascular Microphysiological System (MPS) consisting of a tubular blood vessel lined with Human Umbilical Vein Endothelial Cells (HUVECs) to evaluate endothelial function measured via endothelial permeability and Ca2+ signaling. We evaluated the effect of a mixture of factors associated with inflammation and cardiovascular disease (TNF, VEGF-A, IL-6 at 10ng/ml each) on vascular MPS and inferred that inflammatory mediators contribute to endothelial dysfunction by disrupting the endothelial barrier over a 48-hour treatment and by diminishing coordinated Ca2+ activity over a 1-hour treatment. We also evaluated the effect of peripheral blood mononuclear cells (PBMCs) on endothelial permeability and Ca2+ signaling in the HUVEC MPS. HUVECs were co-cultured with PBMCs either directly wherein PBMCs passed through the lumen or embedded in the supporting collagen hydrogel. We revealed that Phytohemagglutinin (PHA)-M activated PBMCs cause endothelial dysfunction in MPS both through increased permeability and decreased coordinated Ca2+ activity compared to non-activated PBMCs. Our MPS has potential applications in modeling cardiovascular disorders and screening for potential treatments using measures of endothelial function.

bioengineering↗