Table 1 Tissue distribution and function of claudin-5
Tissue | Function | Pathology | Observations |
|---|---|---|---|
Endothelial tissue e.g. brain capillary, lung endothelium | BBB—decrease paracellular permeability | Downregulated in schizophrenia, glioblastoma, Alzheimer’s disease Hemizygous in 22q11DS | Mouse KO—post natal lethality, increased permeability < 800 Da [29] |
Peripheral lymph node | Decrease permeability | – | Claudin-5 ± mice – increased leakage and inflammation following UV exposure [32] |
Cardiomyocytes | Unknown | Downregulated in heart failure [33] | Dystrophin KO – overexpression of claudin-5 prevents cardiomyopathy [34] |
Pancreatic ductal and acinar cells | Unknown | – | – |
Retinal pigment epithelium | Changes in permeability in developing RPE | – | – |
Small/large intestine | Unknown | – | – |
Stomach epithelium | Unknown | – | – |
Seminiferous epithelium | Blood-testis barrier | – | Claudin-5 downregulation and biotin tracer leakage in Etv5 KO mice [35] |
Ovarian epithelium | Theca vascular development | Overexpression associated with aggressive, high-grade ovarian adenocarcinoma [36] | – |
Prostate | Unknown | Overexpressed in prostate adenocarcinoma [37] | – |