Tight junctions (TJs) are complex cell-cell junctions that form a barrier in the stratum granulosum of mammalian skin. Besides forming a barrier themselves, TJs influence other skin barriers, e.g. the stratum corneum barrier, and are influenced by other skin barriers, e.g. by the chemical, the microbiome, or the immunological barrier and likely by the basement membrane. This review summarizes the dynamic interaction of the TJ barrier with other barriers in the skin and the central role of TJs in skin barrier function.
