Fig. 6. AEC-2 cell marker gene expression in SP-C/G6en mice. In situ hybridization using specific probes for TTF-1 (A-D) and SP-C (E-H) was performed on wild-type (A,C,E,G) and SP-C/G6en (B,D,F,H,I) sections from E17.5 (A,B,E-I) and E19.5 (C,D) embryos. Non-radioactive in situ hybridization was utilized for the SP-C probe to better analyze the specific expression pattern, whereas radioactive in situ hybridization was used for TTF-1. TTF-1 expression is observed throughout the airway epithelium in both wild-type (A,C) and SP-C/G6en embryos (B,D). SP-C expression, however, was reduced in SP-C/G6en mice and in some regions almost completely absent from the distal airway epithelium expressing the transgene as demarcated by the SV40 probe (compare adjacent sections in H and I). However, SP-C expression was observed in regions outside the area of transgene expression (F,H, arrowheads). There was no detectable hybridization with the sense probes for TTF-1 and SP-C (data not shown). Asterisks denote proximal airways in A-D. Scale bar: 250 µm (A-D), 125 µm (E,F), 67.5 µm (G,H,I).
