Fig. 2. MTS24 and CD34 reactivity during hair follicle development. (A) Staining of MTS24-Cy3 (red) and keratin 17-FITC (green) in skin obtained from Balb/c mice at E20.5 during embryonic development and at day 2 and day 8 after birth. Keratin 17 was selectively expressed within the developing hair follicles. Note the interfollicular staining of MTS24 and its co-localisation with keratin 17 expression in 2-day-old Balb/c mice (arrowhead). (B,C) Expression of CD34-Cy3 (red), keratin 17-FITC (green) in dorsal skin from Balb/c mice at day 4 (B) and day 6 (C). Note that CD34 was expressed from day 6 after birth but not at day 4 after birth. Red staining of stratum corneum is caused by autofluorescence. (D,E) Frozen sections of dorsal epidermis from K14Nß-cateninER transgenic mice treated with 4OHT for 21 days were immunolabelled for MTS24 (green; D,E) and keratin 14 (red; D) or keratin 17 (red; E). MTS24-positive regions of ectopic follicles are demarcated with brackets (D,E). Nuclei were counterstained (blue) with DAPI (A-C) or ToPro3 (E). HF, hair follicle; IFE, interfollicular epidermis; BG, bulge. Scale bars: 25 µm (A, upper and second panel); 50 µm (A, third panel; B-E).