Figure 7.

POSTN Is Expressed in Vascular Endothelium of the FL

(A) PSTN expression was examined in the E14.5 fetuses using immunohistochemistry on 10-μm formalin-fixed paraffin-embedded sections followed by confocal imaging. Specific antibodies were used to identify the cells expressing POSTN, nuclear counterstaining was done using Hoechst 33342. Regions with compelling levels of POSTN expression; namely, the developing ribs (yellow arrows), diaphragm (white arrows), and the tissue of interest, FL (blue round head arrows), are indicated (n = 4). Scale bar, 1 mm.

(B–D) Enlarged POSTN-expressing regions from the tiles were extracted. (B) Developing ribs showing marrow as well as the mesenchymal tissue (n = 3). Scale bar, 50 μm. (C) Muscular diaphragm (n = 3). Scale bar, 50 μm. (D) Vascular region in the FL tissue (n = 4). Scale bar, 20 μm.

(E) Immuno-staining of the FL sections with endothelial marker CD31 and ECM protein laminin, along with POSTN. The sections were counterstained with Hoechst 33342 (upper panel) (n = 4). Scale bar, 10 μm. The lower panel shows an enlarged part of the section shown in the upper panel. Scale bar, 5 μm).

See also Figure S6.