Figure 6
A representative series of immunohistochemical results from normal human liver and liver tissues from patients with PBC, PSC and ALD showing expression of vimentin, MMP-2, αSMA, ALK5 and pSmad 2/3. (a) A vimentin expressing ductule (red) at the portal tract/hepatocyte interface (black arrow) lies in close proximity to vimentin-expressing fibroblast-like cells (grey arrow)—PBC Stage3. (b) The expression of MMP-2 (red) in a ductular reaction in Stage 4 PSC. (c) Shows the absence of αSMA (FITC: green) from epithelium within a small bile duct, which expresses S100A4 (TRITC: red); αSMA is present within myofibroblasts of the surrounding tissue (Stage 4 PSC). (d) Also in stage 4 PSC, a small bile duct confirms no coexpression of CK19 (TRITC: red) and αSMA (green: FITC-labelled primary antibody). By contrast the accompanying blood vessel is strongly αSMA-positive. (e) In a single-labelled section, a ductule in an infiltrated and fibrotic portal tract expresses S100A4, as do many of the infiltrating cells and hepatocytes (arrowed) at the interface with the parenchyma (end-stage ALD) (f) A single-labelled section from stage 3 PBC showing a bile duct-expressing ALK5 (TGFβRI—brown/black). Hepatocytes and a proportion of the infiltrating cells also express ALK5. (g) Coexpression of S100A4 and pSmad2/3; many of the S100A4 expressing cells (red) in a typical ductular reaction in end-stage alcoholic liver disease (ALD) also show nuclear localisation of the pSmad2/3 phosphoproteins (brown/black; no nuclear counterstain). (h) Negative method control—an ALD section in which primary antibody was replaced with rabbit IgG—counterstain, Mayer's haematoxylin.
