Figure 2

CAIX expression in the placenta, skin, squamous mucosa and skeletal system. The mesenchymal cells of the chorionic plate and umbilical cord retained their CAIX expression until birth (A1, A2). In the epidermis, CAIX expression was limited to the basal layer (B1, F), hair buds (B1) and sebaceous units, hair follicles and the bulges (B2, arrow and inserts). Between 18 to 24 months after birth, CAIX expression was restricted to the hair follicles, sebaceous units, and the infundibulum (C). In the skeletal system, persistent high levels of CAIX immunoreactivity was seen in the chondrocytes, mesenchymal condense (E, F, G) and tendoligamental tissues (G, H). The basal layer of squamous mucosa of the nose (D) and oral cavity (G) also expressed CAIX. W = gestational age in weeks; M = postnatal age in months. Original magnifications: A1, A2, B, C and H (20×); D and G (4×); E (10×) and F (40×).