Pichinde virus induces microvascular endothelial cell permeability through the production of nitric oxide

Area of Science:

• Virology
• Immunology
• Cell Biology

Background:

• Pichinde virus (PIC) is an arenavirus known to infect various cell types.
• Endothelial cells form critical barriers in blood vessels, and their dysfunction is implicated in disease.
• Nitric oxide (NO) is a signaling molecule with diverse roles, including immune responses and vascular regulation.

Purpose of the Study:

• To investigate the interaction between Pichinde virus and human endothelial cells.
• To determine the role of nitric oxide (NO) in Pichinde virus infection of endothelial cells.
• To elucidate the pathogenic mechanisms of PIC infection in endothelial barrier function.

Main Methods:

• Infection of human endothelial cells with Pichinde virus (PIC).
• Measurement of inducible nitric oxide synthase (iNOS) gene expression and nitric oxide (NO) production.
• Assessment of endothelial cell monolayer permeability using an in vitro model.
• Inhibition of NO synthesis using a specific inhibitor.
• Quantification of viral titer and activated caspases.

Main Results:

• PIC successfully infected human endothelial cells, a novel finding.
• PIC infection led to increased iNOS gene expression and NO production.
• Enhanced endothelial cell permeability was observed, which was reversed by NO synthase inhibition.
• NO inhibition did not affect viral load or caspase activation, suggesting a pathogenic role for NO.

Conclusions:

• Pichinde virus infection induces NO production in human endothelial cells.
• The induced NO plays a pathogenic role in increasing endothelial barrier permeability.
• NO production during PIC infection does not appear to exert antiviral effects or modulate apoptosis in this context.