Fig. 1.

ALP expression in human skin cells and murine skin. A, Gene expression of ALPs in human epidermal keratinocytes and dermal fibroblasts analyzed by real-time qPCR. B, Values from analyses in A shown for MEP1A and MEP1B Kera, keratinocytes; Fibro, fibroblasts. C, Murine adult WT back skin analyzed for ALP gene expression by real-time qPCR. D, Staining of murine WT tail skin for meprin α and meprin β discloses similar distribution as previously reported for human skin [6], localization of meprin α primarily to basal and spinous layers and meprin β primarily to granular layers of keratinocytes. In addition meprin α is seen in the dermis (arrows), also similar to previous staining of healthy human skin [7]. Nuclei were counterstained with DAPI (blue). Rabbit pre-immune sera was used as isotype (Iso) control. Scale bar = 50 μm. A–C, individual values from different donor cells (n = 4–7), mean ± S.D. are shown, *P < 0.05; **P < 0.01; ***P < 0.001; ****P < 0.0001 as analyzed by one-way ANOVA with Tukey’s correction. (For interpretation of the references to colour in this figure legend, the reader is referred to the web version of this article.)