Figure 3.

Immunolocalization of insulinlike growth factor binding protein 4 (IGFBP-4), N-cadherin, and matrix metalloproteinase 1 (MMP-1) in IPF and normal lungs. (A) MMP-1 immunoreactive protein was found in alveolar epithelial cells. It can be noticed that the enzyme is virtually absent in fibroblastic foci (original magnification, 40×). (B) IGFBP-4 immunoreactive bronchiolar basal epithelial cells in IPF lungs (40×). (C) N-cadherin immunoreactive protein was observed in alveolar epithelial cells usually covering fibroblastic foci (40×). (D) Normal lungs were usually negative for the three molecules as exemplified for N-cadherin (40×). (E) A negative control omitting the primary (in this case, IGFBP-4) antibody (40×). Results illustrate the analysis of six IPF and five control lungs.