TGF-β1 vaccination accelerates hepatocyte proliferation in the fibrotic liver.

<p>Cell proliferation was determined by PCNA immunostaining (A). PCNA-positive nuclei were counted and expressed as a percentage of the total number of hepatocyte nuclei (PCNA labeling index, PCNA LI) (B). Repeated CCl₄ injections induced elevated hepatocyte proliferation with PCNA-positive hepatocytes predominantly distributed around the fibrous septa, whereas vaccination with the TGF-β1 kinoids led to further increases in the percentages of the PCNA-expressing hepatocytes in mouse livers. Scale bars = 100 μm. The error bars indicate SEM.