Long-term cultures of human fetal liver cells: a three-dimensional experimental model for monitoring liver tissue development.
OBJECTIVE
The present study describes an embryonic-fetal liver culture system which allows morphogenetic interactions consistent with the development of the hepatocellular function.


METHODS
Intact livers from 8-12-week embryos were soaked in an extracellular matrix at 4 degrees C and gently dissociated without any enzymatic treatment. The resulting spherical hepatic units were cultured in a chemically defined serum-free medium and seeded into an extracellular matrix layer. Adherent three-dimensional tissue specimens were examined at various times by light and electron microscopy to evaluate the maintenance of hepatocyte morphology.


RESULTS
The liver cells were viable for over 4 months; erythropoietic burst colonies were detected for longer than 6 weeks. Parallel detection of bile salt production in the medium by high performance liquid chromatography proved liver tissue functionality. Bile salt composition revealed predominance of taurine-conjugates rather than glycine. Maximum bile salt concentration (approximately 3 months) coincided with structural and ultrastructural observations indicating a marked decline in hematopoiesis, well-defined biliary canaliculi and formation of an organ-like structure.


CONCLUSIONS
This three-dimensional culture system recapitulates fetal liver development with: (i) initial proliferation of both fetal erythropoietic and hepatic cells and (ii) subsequent shut-off of erythropoiesis and a shift to a more advanced stage of hepatocyte function, such as bile salt secretion.
Sargiacomo
M
M
Department of Hematology, Istituto Superiore di Sanita', Rome, Italy.
Onori
P
P
Bravo
E
E
Franchitto
A
A
Cantafora
A
A
Barca
S
S
Peschle
C
C
Gaudio
E
E
D001647:Bile Acids and Salts / Q000378:metabolism; D002478:Cells, Cultured; D005314:Embryonic and Fetal Development / Q000502:physiology; D005333:Fetus / Q000166:cytology / Q000378:metabolism / Q000502:physiology*; D006801:Humans; D008099:Liver / Q000166:cytology / Q000196:embryology* / Q000378:metabolism; D008854:Microscopy, Electron; D008855:Microscopy, Electron, Scanning; D013997:Time Factors
D001647:Bile Acids and Salts