Porcine circovirus 2 (PCV2) induces a procoagulant state in naturally infected swine and in cultured endothelial cells.
Porcine circovirus 2 (PCV2) is the primary causative agent of porcine circovirus disease (PCVD). PCVD is an emerging disease that has been reported worldwide, associated with wasting, lymphoid depletion, enteritis, pneumonia, vasculitis, ischemic lesions, and necrotizing dermatitis. Although PCVD causes considerable economic losses, the pathogenesis of PCV2 has not been fully understood. The aim of the present work was to study the participation of hemostatic system and of vascular endothelium in PCV2 infection, as well as their possible role in PCVD pathogenesis. Our results showed that naturally PCV2-infected swine displayed a prothrombotic state in vivo, since a diminished coagulation time (recalcification time, activated partial thromboplastin time and prothrombin time), a higher platelet aggregation ability (despite a diminished platelet blood count), and an increased thrombin plasma activity (associated with a reduced fibrinogen level) were observed. The PCV2-infected animals showed vasculitis and positive staining for PCV2 antigen in capillary vessels. Furthermore, PCV2-infected endothelial cells displayed an activated phenotype, characterized by an increase in cell surface procoagulant activity. Moreover, the PCV2-infected endothelial cells pre-treated with exogenous thrombin displayed an increased viral load. This work reports, for the first time, the role of the hemostatic system and of endothelium in the pathogenesis and infectivity of PCV2. The study reinforces the importance of the phenomena which occur during PCV2 infection, and affords a better knowledge of the mechanisms behind the pathophysiology of PCVD.
Marks
Fernanda S
FS
Laboratório de Virologia, Faculdade de Veterinária, Universidade Federal do Rio Grande do Sul, Av. Bento Gonçalves, 9090, 91540-000 Porto Alegre, RS, Brazil.
Reck
José
J
Almeida
Laura L
LL
Berger
Markus
M
Corrêa
André M R
AM
Driemeier
David
D
Barcellos
David E S N
DE
Guimarães
Jorge A
JA
Termignoni
Carlos
C
Canal
Cláudio W
CW
D000818:Animals; D002460:Cell Line; D002478:Cells, Cultured; D018173:Circoviridae Infections / Q000503:physiopathology* / Q000821:virology; D017925:Circovirus / Q000502:physiology*; D042783:Endothelial Cells / Q000821:virology*; D005340:Fibrinogen / Q000378:metabolism; D006490:Hemostatics / Q000494:pharmacology; D006801:Humans; D007150:Immunohistochemistry; D010974:Platelet Aggregation / Q000187:drug effects; D016133:Polymerase Chain Reaction; D013552:Swine; D013553:Swine Diseases / Q000378:metabolism / Q000503:physiopathology* / Q000821:virology; D013917:Thrombin / Q000494:pharmacology; D014779:Virus Replication / Q000187:drug effects
D006490:Hemostatics; D005340:Fibrinogen; D013917:Thrombin