Figure 2

Indirect immunofluorescence labeling and CLSM analysis of developing human epidermis for NF1 protein. (a-f) Labeling with NF1GRP(D) antibody (dilution of 1:500 in fetal samples and dilution of 1:10 in neonatal (NB) sample). (a) At 8 weeks EGA, developing epidermis consists of basal and periderm cell layers. Both cell layers are intensely labeled and reveal a fibrillar labeling pattern. Insert: higher magnification of cytoplasmic compartment of a periderm cell. (b) At 11 weeks EGA, an intermediate cell layer is detectable between the basal and the periderm cell layers. The basal cells show a fibrillar labeling pattern, while labeling of periderm cells is diffuse. The intermediate layer shows less intense immunoreaction for NF1 protein. (c) At 13 weeks EGA, the suprabasal epidermis consists of multiple cell layers. The basal cells show fibrillar labeling pattern for NF1 protein while the periderm cells are characterized with a diffuse and faint immunoreaction. (d) A transverse section of basal cells at 13 weeks EGA. Cells have a perinuclear web of fibrils positive for NF1 protein (*). Some fibrils are directing towards desmosomes (arrows) (see also figure 5B, a and c). (e,f) In 21-week-old and in neonatal (NB) epidermis the basal cells show diffuse cytoplasmic labeling for NF1 protein. (g) NF1 specific antiserum NF1as159 labels all epidermal cell layers at 14 weeks EGA. The labeling is fibrillar in the basal cells. (h) Also NF1 specific antibody NF1ab67 labels all cell layers, but in a more punctuate manner. Scale bars 10 μm in a-c, g, h; 5 μm in d; 20 μm in e, f. Insert in (a) 30 μm.