Histological analysis of epidermis structure at E18.5 dpc and P0.

<p><b>(A)</b> Hematoxylin and eosin stained skin sections from newborn mice showed a reduced granular layer and acanthosis in epidermis of Sp5^A135X/A135X pups; no obvious defects were observed in the other groups, Scale bar, 100 μm. <b>(B)</b> Analysis of epidermal differentiation in the skin from E18.5 dpc embryos. Sections were stained with antibodies against keratin14 (Krt14), keratin6 (Krt6) and fillagrin (Flg). Increased expression of Krt14 was observed in Sp5^A135X/A135X embryos, which also strongly express the stress marker Krt6. Expression of both Krt6 and Krt14 was not altered in Klk5^-/-Sp5^A135X/A135X, Klk7^-/-Sp5^A135X/A135X and Klk5^-/-Klk7^-/-Sp5^A135X/A135X. Flg staining revealed absence of profilaggrin granules in Sp5^A135X/A135X and Klk7^-/-Sp5^A135X/A135X embryos whereas these granules were present in wt, Klk5^-/-Sp5^A135X/A135X and Klk5^-/-Klk7^-/-Sp5^A135X/A135X mice (white arrowheads). Scale bar, 50 μm.