Altered gene expression in human brain microvascular endothelial cells in response to the infection of influenza H1N1 virus

Influenza viruses not only cause respiratory illness, but also have been reported to elicit neurological manifestations following acute viral infection.

The central nervous system (CNS) has a specific defense mechanism against pathogens structured by cerebral microvasculature lined with brain endothelial cells to form the blood–brain barrier (BBB).

To investigate the response of human brain microvascular endothelial cells (hBMECs) to the Influenza A virus (IAV), we inoculated the cells with the A/WSN/33 (H1N1) virus.

We then conducted an RNAseq experiment to determine the changes in gene expression levels and the activated disease pathways following infection.

The analysis revealed an effective activation of the innate immune defense by inducing the pattern recognition receptors (PRRs).

Along with the production of proinflammatory cytokines, we detected an upregulation of interferons and interferon-stimulated genes, such as IFN-β/λ, ISG15, CXCL11, CXCL3 and IL-6, etc.

Moreover, infected hBMECs exhibited a disruption in the cytoskeletal structure both on the transcriptomic and cytological levels.

The RNAseq analysis showed different pathways and candidate genes associated with the neuroactive ligand-receptor interaction, neuroinflammation, and neurodegenerative diseases, together with a predicted activation of the neuroglia.

Likewise, some genes linked with the mitochondrial structure and function displayed a significantly altered expression.

En masse, this data supports that hBMECs could be infected by the IAV, which induces the innate and inflammatory immune response.

The results suggest that the influenza virus infection could potentially induce a subsequent aggravation of neurological disorders.