Table I.

Antigenic profiles of hHpSC and hepatoblasts

MarkershHpSCs on plastic
 and in KM1hHpSCs on STO feeders
 and in KM1Hepatoblasts
AFP2+++ in those from fetal liver; ± in those from
 postnatal livers
Albumin2− or ±++
P450-3A42
P450-A72+
CK 8/18, CD29, CAM 5.2++++++
CK192++++ particulate staining in cytoplasm
+++
EpCAM2Cytoplasm and membrane++ at membrane surface but not cytoplasm
NCAM2+++
Indian Hedgehog+++; in center of cells++
Sonic Hedgehog+++ at periphery of cells++
ICAM-12+ (Fig. 6)
Claudin 32+++
CD44H 4++++++
CD133/12++++++
Telomerase5+++ +++
CD1172Debatable9
Mesenchymal6 cell markers
Endothelial cell markers7
Hemopoietic markers8
  • +, weakly expressed; ++, expressed strongly; +++, expressed very strongly.

  • 1 Description of KM development (9) and a review for its details of its preparation have been previously provided (56).

  • 2 Phenotypic characterization of >20 genes by RT-PCR and Western blot analyses was done on hHpSCs, hepatoblasts, and hepatocytes from livers from donors of varying age (16).

  • 3 More extensive studies on hedgehog signaling are presented elsewhere (39).

  • 4 More extensive studies on hyaluronan receptors and their relevance to use of hyaluronan hydrogels for ex vivo maintenance of hHpSCs are given elsewhere (57).

  • 5 Telomerase activity has been measured in hHpSCs, hepatoblasts versus in mature liver cells (unpublished data).

  • 6 Mesenchymal markers: CD146, desmin, and α-smooth muscle actin.

  • 7 Endothelial cell markers: VEGFr (also called KDR), Von Willebrand factor, and CD31.

  • 8 Hemopoietic cell markers: CD45, CD34, CD14, CD38, Thy 1 (CD90), and Glycophorin A.

  • 9 It is not detected on freshly isolated EpCAM+ cells from fetal or postnatal livers. RNA for it is enriched in EpCAM+ cells (16). It is variably found in hHpSC colonies from fetal but not adult livers and, when found, it is always near or overlapping with the companion cells. Immunoselection for it does not yield hHpSCs. We suspect it is on angioblasts, but not the hHpSCs (and for certain is not on hepatoblasts).