Tight junctions form a barrier in human epidermis.
Tight junctions (TJ) are cell-cell junctions that have proved to form a paracellular barrier for solutes and water between cells of epithelia, including the stratum granulosum of the stratified epithelium of the epidermis of newborn mice. In mice lacking claudin-1, a major barrier-forming TJ component, this barrier was abolished. However, the role of TJ in human skin is controversially discussed as unambiguous data were missing so far. Here, we investigated TJ barrier function in healthy human skin as well as in skin samples from psoriatic lesions which are characterized by an altered localization of TJ proteins. We demonstrate for human skin that occludin- and claudin-1-positive sites in the stratum granulosum form a barrier for extracellular biotin-SH (557Da) and that in psoriatic skin the localization of the barrier and the TJ proteins are altered in parallel.
Kirschner
Nina
N
Department of Dermatology and Venerology, University Hospital Hamburg-Eppendorf, Martinistrasse 52, 20246 Hamburg, Germany.
Houdek
Pia
P
Fromm
Michael
M
Moll
Ingrid
I
Brandner
Johanna M
JM
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002478:Cells, Cultured; D062445:Claudin-1; D000078404:Epidermal Cells; D004817:Epidermis / Q000378:metabolism* / Q000473:pathology; D005260:Female; D006801:Humans; D008297:Male; D008565:Membrane Proteins / Q000378:metabolism*; D008875:Middle Aged; D062793:Occludin; D011565:Psoriasis / Q000378:metabolism; D019108:Tight Junctions / Q000378:metabolism*
C568108:CLDN1 protein, human; D062445:Claudin-1; C568113:Cldn1 protein, mouse; D008565:Membrane Proteins; C568985:OCLN protein, human; D062793:Occludin; C568986:Ocln protein, mouse