A Normal Range of KL-6/MUC1 Independent of Elevated SP-D Indicates a Better Prognosis in the Patients with Honeycombing on High-Resolution Computed Tomography
Figure 3
Immunohistochemical distribution of SP-D and KL-6/MUC1 in control and IPF lungs. ((a) and (b)) In control lungs, alveolar type II epithelial cells show cytoplasmic staining for SP-D (in red). In contrast, KL-6/MUC1 (in green, (b)) distributes extracellular surface facing alveolar space without cytoplasmic or basal-lateral side expression. The dotted square in (a) is the same section with (b) observed by fluorescence (scale bar = 10 μm). (c) Double immunohistochemistry of SP-D (in brown) and CD34-positive alveolar capillary endothelial cells (in red) in IPF lung tissues. The alveolar type II epithelial cells with SP-D expression are always in close contact with alveolar capillaries (indicated by arrows). Counter staining by elastic-Goldner staining (scale bar = 10 μm). (d) In IPF lung tissues, regenerated type II epithelial cells are increased with more intense expression of SP-D (in red) than control lungs. These increased type II epithelial are also in close contact with alveolar capillaries (in green). Nuclei are stained in blue (scale bar = 10 μm). ((e), (f)) In honeycomb cysts in IPF lings, thick mucus with immunoreactive for KL-6/MUC1 (in brown, (e)) were accumulated in contrast to SP-D (in brown, (f)). Counterstained by elastica-Goldner staining (scale bars = 100 μm).
