Volume 281, October 2001
Volume 25, October 2001

Pages L1001-L1010, 2001: K. R. S. Brown, K. M. England, K. L. Goss, J. M. Snyder, and M. J. Acarregui. "VEGF induces airway epithelial cell proliferation in human fetal lung in vitro." On pages L1003-L1005 (Figs. 1, 2, 3, and 5), the figures should have appeared in color. The correct figures and their legends follow.

View larger version (132K): [in this window] [in a new window]   Fig. 1.   Photomicrographs of immunoreactivity for KDR (indicated by the brown staining) in midtrimester human fetal lung tissue and explants cultured for 4 days. A and B: immunoreactivity detected by the Santa Cruz antibody (A) and by the Sigma antibody (B) in human fetal lung tissue. C and D: immunoreactivity for KDR in lung explants detected by the Santa Cruz antibody (C) and by the Sigma antibody (D). E: KDR immunoreactivity in mesenchymal and arterial endothelial cells. F: control tissue incubated with nonimmune mouse IgG instead of primary monoclonal antibody against KDR demonstrates the specificity of the antibody. Examples of immunoreactive distal airway epithelial cells (filled arrowheads), mesenchymal cells (open arrowheads), and a small artery (*) are indicated. Bar = 50 µm.

View larger version (60K): [in this window] [in a new window]   Fig. 2.   Photomicrographs of human fetal lung explants incubated in the absence (A) and presence (B) of vascular endothelial growth factor (VEGF, 100 ng/ml) for 4 days. The connective tissue (CT) and the lumens of the distal airways (L) are indicated. Immunoreactivity for KDR is indicated by the brown color and is not noted to be different between control and VEGF-treated tissues. The lumens of the distal airways and the relative amount of epithelial cells are increased and the relative amount of connective tissue is decreased in the VEGF-treated explants (B) compared with control (A). Bar = 50 µm.

View larger version (65K): [in this window] [in a new window]   Fig. 3.   Photomicrograph of immunoreactivity for neuropilin-1 in human fetal lung tissue (A) and human fetal lung tissue explant (B) incubated for 4 days. Neuropilin-1 immunoreactivity is indicated by the brown staining and was observed primarily in the distal airway epithelial cells as indicated by the arrows. Bar = 50 µm.

View larger version (99K): [in this window] [in a new window]   Fig. 5.   Photomicrographs of bromodeoxyuridine (BrdU) immunoreactivity in human fetal lung explants incubated in the presence of BrdU and the absence or presence of VEGF. Human fetal lung explants were cultured in the absence or presence of VEGF (50 ng/ml) , with 2 mM BrdU added for the final 24 h. Tissue was harvested after 4 days of incubation, embedded, sectioned, and then immunostained for the presence of BrdU (indicated by the dark brown/black staining). Control explants (A) exhibit evidence of BrdU immunoreactivity; however, in the VEGF-treated explants (B), there is increased BrdU immunoreactivity, primarily in the epithelial cells lining the lumens of the prealveolar ducts (examples indicated by black arrows) but also in mesenchymal cells (examples indicated by red arrows).