Stains & CD markers

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PubMed Search: claudins

Nat Pernick, M.D.
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Cite this page: Pernick N. Claudins. website. Accessed June 8th, 2023.
Claudins - general
  • Multigene family of integral membrane proteins active in tight junction formation and function
  • Claudins were first named in 1998 by Japanese researchers Mikio Furuse and Shoichiro Tsukita at Kyoto University, based on the Latin claudere ("to close"), suggesting the barrier role of these proteins (J Cell Biol 1998 Jun 29;141:1539)
  • Most claudin genes appear decreased in cancer, while CLDN3, CLDN4 and CLDN7 are elevated in several malignancies (BMC Cancer 2006;6:186)
  • Pathophysiology:
    • Tight junctions (zonula occludens) form continuous barrier to fluids across epithelium and endothelium; regulate paracellular permeability and maintain cell polarity by blocking movement of transmembrane proteins between apical and basolateral cell surfaces (Annu Rev Cell Dev Biol 2006;22:207)
    • Tight junctions are composed of claudin and occludin proteins, which join the junctions to the cytoskeleton
    • Claudin family has > 20 integral membrane proteins, expressed in tissue specific pattern that may determine strength and properties of epithelial barrier; usually cells from a specific organ express multiple claudin proteins
  • Positive staining - normal: epithelial and endothelial cells
Microscopic (histologic) images

Images hosted on other servers:

Claudin5: normal and malignant (breast)

Claudin5: serous papillary adenocarcinoma (ovary)

Claudin7: synovial sarcoma

Claudin18: normal lung and stomach (splice variant 2)

Claudin18: PanIN (left), infiltrating ductal carcinoma (right)

Claudin18: carcinomas
of stomach, esophagus,
ovary (splice variant 2)

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