Effect of inactivated conditioned media from DENV-2-infected endothelial cells on epithelial cell healing: live cell imaging analysis

Dengue virus (DENV) infection presents a spectrum of clinical presentations, ranging from mild febrile illness to severe, life-threatening conditions such as dengue hemorrhagic fever (DHF) and dengue shock syndrome (DSS). These severe outcomes are primarily associated with microvascular dysfunction, which is characterized by the release of soluble factors such as cytokines and growth factors from infected endothelial cells, as well as extensive intracellular alterations at the cellular and molecular levels. The precise role of endothelial cells in the pathogenesis of dengue remains incompletely understood. Previous research has suggested that DENV can stimulate migratory responses in endothelial cells through the release of soluble factors and miRNAs linked to cell migration. This study investigated the impact of virus-free supernatants from DENV-infected endothelial cells on the migratory behavior of Vero cells using a wound healing assay facilitated by live cell imaging. Our findings revealed a significant induction of cell migration, wound closure, and enhanced filopodium formation in cells treated with supernatants from DENV-infected cells compared to those from uninfected cells, demonstrating a migratory phenotype. Importantly, upregulation of miRNAs associated with cell migration and remodeling, including miR-21-3p, miR-146a-5p, and miR-484, was observed, while the expression of miR-423-5p, a nononcogenic miRNA, remained unchanged. These results advance our understanding of DENV’s ability to stimulate migratory phenotypes in uninfected cells through intercellular signaling in response to extracellular factors produced during DENV infection, potentially influencing systemic alterations in DENV-infected individuals.