Figure 4.

Alterations of EfnB2 reverse signaling disrupted distal lung morphometry. Hematoxylin-and-eosin–stained sections from EfnB2^LacZ/6YFΔV adult inflation-fixed lungs (at age 8 wk) indicated that alterations of reverse Efnb2 signaling exhibited a significant (P < 0.001) reduction in secondary alveolar crests at age 8 weeks (B and D, arrows identify alveolar crests) compared with wild-type control mice (A and C, arrows identify alveolar crests; see also E). Furthermore, the mean linear intercept was significantly (P = 0.01) increased at age 8 weeks in EfnB2^LacZ/6YFΔV mice (B and D, double-headed arrow; see also F), consistent with alveolar hypoplasia, compared with WT control mice (A and C, double-headed arrow; see also F). An asterisk denotes that statistical significance was reached. Magnification in A and B, scale bar = 50 μm; and in C and D, scale bar = 25 μm.