Factor VIII‐related antigen detects transformation of liver sinusoidal to vascular endothelium in hepatic fibrosis of elderly cadavers (916.2)

Abstract

Morphological transformation of liver sinusoidal endothelium (SE) to vascular endothelium (VE) is a significant histopathological lesion associated with severe liver fibrosis. In the process, the SE expresses a VE phenotypic marker FVIIIRAg. Because liver fibrosis is inherent to human aging and is also prevalent in elderly cadavers, this study examined FVIIIRAg expression in the aged liver of cadavers. Immunohistochemically staining revealed that the VE of portal tracts and central veins stained uniformly for FVIIIRAg, providing an internal positive control. The incidence of FVIIIRAg expression in SE was low in livers with minimal fibrosis or perisinusoidal fibrosis, but was increased in livers with advanced septal fibrosis and cirrhosis. FVIIIRAg positive endothelial cells occurred in loose aggregates or singly in the periportal, periseptal, mid‐lobular and centrilobular areas, as well as in foci of the parenchyma showing severe fibrotic change. The immune deposits of FVIIIRAg were patchy and discontinuous along the sinusoidal lining, probably representing focal transformation of SE to VE. Thus, FVIIIRAg detects transformation of SE to VE phenotype in advanced liver fibrosis of aged cadavers. Formation of VE may impair the exchange of materials between the sinusoidal blood and liver parenchyma, causing hepatic dysfunction and disease susceptibility associated with fibrosis in the aging liver.