Regulation of C/EBPδ in human skin. Fixed samples of two representative human interfollicular skin sections were double stained with anti-p63 4A4 and the C/EBPδ antibodies. Analysis was performed by Immunofluorescence Confocal microscopy. Arrows in the merge Panel indicate nuclear staining of cells that are positive for both antibodies, in the basal layer. Yellow signals in the spinous layer refer to cells co-expressing the two factors. B, basal layer; S, spinous layer; G, granulous layer; C, corneum stratum. In the CTL Panels, we stained a skin section only with mouse and rabbit secondary antibodies used above.