Sections of immunohistochemically stained skin constructs cultivated <i>in vitro</i>.

<p>Skin constructs were cultivated <i>in vitro</i> at the air-liquid-interface with differentiation medium for 11 days. The indicated time points in A–C are valid for the whole respective column. E-cadherin expression is absent on day 0 but can be detected on days 5 and 11 (A–C) while cytokeratin 14 expression is clearly visible at all time points in the whole epidermis (D–F). While nearly all cells exhibit Ki67 staining on day 0, only few cells do so at days 5 and 11 (G–I). The corresponding negative controls of the stainings (skin constructs without first antibody) are shown below (K – e-cadherin, L – cytokeratin 14, M – Ki67). All scale bars depict 100 µm.