FIG. 5.

Transient α9 expression in the primordial thoracic duct and adjacent aorta of E14 mouse embryo. Frozen sections fixed with acetone were stained with affinity-purified anti-α9 polyclonal antiserum (brown staining). (A) Section of an α9^+/+ E19 embryo (original magnification, ×200), demonstrating staining of the aorta but not of the adjacent thoracic duct (Td). (B) Section of an α9^+/+ E14 embryo at the same magnification, demonstrating staining of both the aorta and the adjacent tissue that will ultimately form the thoracic duct. Airway smooth muscle (ASM) also demonstrates α9 immunoreactivity. (C) Enlargement of the same section shown in panel B.