Apoptosis of biliary epithelial cells in primary biliary cirrhosis and primary sclerosing cholangitis.
OBJECTIVE
Primary biliary cirrhosis (PBC) is an autoimmune disease characterized by inflammatory destruction of small bile ducts. Primary sclerosing cholangitis (PSC) is a different, presumed autoimmune cholestatic liver disease where the bile ducts are also destroyed. In this study, apoptosis and portal triad inflammation in liver tissue from patients with PBC is examined and compared to that from patients with PSC and patients with normal liver.


METHODS
Explanted liver tissue from patients with PBC and PSC and normal liver from patients with metastases to liver were examined. The liver samples were stained for apoptosis using the terminal deoxynucleotidyl triphosphate (TdT)-mediated deoxyuridine triphosphate nick end labelling (TUNEL) assay. The biliary epithelial cells (BEC) were then scored on the basis of their TUNEL stain and the degree of periductal inflammation.


RESULTS
In PBC, apoptosis of BEC, as detected by the TUNEL assay, was significantly increased in the presence of inflammation. Regardless of the presence or absence of inflammation, the small bile ducts in PBC liver tissue exhibited greater evidence of apoptosis than did similar ducts from PSC or control livers.


CONCLUSIONS
These findings suggest that in PBC, unlike PSC, the apoptosis of BEC in PBC is secondary to the invasion of inflammatory cells.
Tinmouth
Jill
J
Department of Medicine, University Health Network, Toronto, Ontario, Canada.
Lee
Mary
M
Wanless
Ian R
IR
Tsui
Florence W L
FW
Inman
Robert
R
Heathcote
E Jenny
EJ
D000328:Adult; D017209:Apoptosis; D001653:Bile Ducts, Intrahepatic / Q000473:pathology*; D015209:Cholangitis, Sclerosing / Q000473:pathology*; D004247:DNA / Q000032:analysis; D004847:Epithelial Cells / Q000473:pathology; D005260:Female; D006801:Humans; D020287:In Situ Nick-End Labeling; D008105:Liver Cirrhosis, Biliary / Q000473:pathology*; D008297:Male; D008875:Middle Aged
D004247:DNA