Toscana virus infects dendritic and endothelial cells opening the way for the central nervous system.
Toscana virus (TOSV) is a Phlebovirus responsible for human neurological infections in endemic Mediterranean areas. The main viral target is the central nervous system, with viremia as a way of dissemination throughout the host. This study was aimed at understanding the spread of TOSV in the host by identifying the cell population infected by the virus and the vehicle to the organs. In vivo studies provided evidence that endothelial cells are infected by TOSV, indicating their potential role in the diffusion of the virus following viremic spread. These results were further confirmed in vitro. Human peripheral mononuclear blood cells were infected with TOSV; only monocyte-derived dendritic cells were identified as susceptible to TOSV infection. Productive viral replication was then observed in human monocyte-derived dendritic cells (moDCs) and in human endothelial cells by recovery of the virus from a cell supernatant. Interleukin-6 was produced by both cell types upon TOSV infection, mostly by endothelial cells, while moDCs particularly expressed TNF-α, which is known to induce a long-lasting decrease in endothelial cell barrier function. These cells could therefore be implicated in the spread of the virus in the host and in the infection of tissues that are affected by the disease, such as the central nervous system. The identification of in vitro and in vivo TOSV cell targets is an important tool for understanding the pathogenesis of the infection, providing new insight into virus-cell interaction for improved knowledge and control of this viral disease.
Department of Medical Biotechnologies, University of Siena, V.le Bracci, 1, 53100, Siena, Italy. mariagrazia.cusi@unisi.it.
Maria Grazia
MG
Cusi
Department of Medical Biotechnologies, University of Siena, V.le Bracci, 1, 53100, Siena, Italy.
Claudia
C
Gandolfo
Department of Medical Biotechnologies, University of Siena, V.le Bracci, 1, 53100, Siena, Italy.
Chiara
C
Terrosi
Department of Medical Biotechnologies, University of Siena, V.le Bracci, 1, 53100, Siena, Italy.
Gianni
G
Gori Savellini
Department of Medicine, Surgery, and Neurosurgery, Pathological Anatomy Section, University of Siena, V.le Bracci 1, 53100, Siena, Italy.
Giuseppe
G
Belmonte
Department of Medicine, Surgery, and Neurosurgery, Pathological Anatomy Section, University of Siena, V.le Bracci 1, 53100, Siena, Italy.
Clelia
C
Miracco
D000818:Animals; D002044:Bunyaviridae Infections / Q000378:metabolism / Q000473:pathology / Q000821:virology*; D002454:Cell Differentiation; D002463:Cell Membrane Permeability; D002490:Central Nervous System / Q000378:metabolism / Q000821:virology; D002522:Chlorocebus aethiops; D003713:Dendritic Cells / Q000378:metabolism / Q000821:virology*; D042783:Endothelial Cells / Q000378:metabolism / Q000821:virology*; D005260:Female; D054884:Host-Pathogen Interactions; D006801:Humans; D015850:Interleukin-6 / Q000096:biosynthesis; D051379:Mice; D008807:Mice, Inbred BALB C; D009000:Monocytes / Q000378:metabolism / Q000821:virology; D061251:Primary Cell Culture; D029301:Sandfly fever Naples virus / Q000472:pathogenicity* / Q000502:physiology; D014409:Tumor Necrosis Factor-alpha / Q000096:biosynthesis; D014709:Vero Cells; D014779:Virus Replication / Q000235:genetics*
C508600:IL6 protein, human; D015850:Interleukin-6; D014409:Tumor Necrosis Factor-alpha
Infection; Target cells; Toscana virus