CLDN5 and infection: Infection of a lung airway-on-a-chip lined by human lung microvascular ECs (HMVEC-L) and normal human bronchial epithelial (NHBE) cells suggested that the decrease of Claudin-5 (CLDN5) expression caused by SARS-CoV-2 leads to the disruption of vascular barrier in the lung and fluvastatin is a potential therapeutic drug to upregulate the CLDN5 expression [22].