Transdifferentiation into biliary ductular cells of hepatocytes transplanted into the spleen.
OBJECTIVE
Transplantation of rat hepatocytes into the syngeneic rat spleen results in the appearance of cytokeratin (CK)7 and CK19 positive biliary cells that form ductules. We examined whether hepatocytes are the origin of these biliary ductular cells.


METHODS
We transplanted rat dipeptidyl peptidase IV (DPPIV) positive hepatocytes into the liver of retrorsine-treated and partially hepatectomised DPPIV negative rats, which resulted in proliferation of DPPIV positive hepatocytes in the liver. Two months later, hepatocytes were prepared from chimaeric livers of these rats and transplanted into the spleen of DPPIV negative rats. Four weeks later, the expression of DPPIV in CK7 positive ductules in the spleen was examined by immunofluorescent double-staining.


RESULTS
In the spleen of DPPIV negative rats transplanted with hepatocytes prepared from the chimaeric livers, DPPIV was found to be expressed in some CK7 positive biliary ductules where only a fraction of cells expressed DPPIV, whereas in the spleen of DPPIV negative rats transplanted with hepatocytes from livers of DPPIV positive rats, DPPIV was expressed in all CK7 positive biliary ductules.


CONCLUSIONS
The present study indicates that hepatocytes transplanted into the spleen could transdifferentiate into biliary cells that aggregate to form ductular structures.
Watanabe
Hirofumi
H
Department of Pathology, Hyogo College of Medicine, Hyogo, Japan.
Hata
Masaki
M
Terada
Nobuyuki
N
Ueda
Haruyasu
H
Yamada
Naoko
N
Yamanegi
Koji
K
Ohyama
Hideki
H
Kakihana
Michiko
M
Okamura
Haruki
H
Nakasho
Keiji
K
D000818:Animals; D001652:Bile Ducts / Q000166:cytology*; D054338:Cell Transdifferentiation / Q000502:physiology*; D018819:Dipeptidyl Peptidase 4 / Q000378:metabolism; D005260:Female; D005455:Fluorescent Antibody Technique; D022781:Hepatocytes / Q000166:cytology* / Q000637:transplantation*; D053552:Keratin-7 / Q000378:metabolism; D051381:Rats; D011916:Rats, Inbred F344; D013154:Spleen / Q000166:cytology
D053552:Keratin-7; D018819:Dipeptidyl Peptidase 4