HepaRG™ is an immortalised cell line with four main features:
→ 1. HepaRG™ is a highly stable cell line
1. HepaRG™ is a highly stable cell line
HepaRG™ karyotype at passage 12.
2. HepaRG™ is infinitely proliferating HepaRG™ proliferating progenitors
Asub-diploid karyotype showing only few alterations. This karyotype is highly stable for up to 20 passages.
An homogenous population of undifferentiated hepatic progenitors with morphological and functional characteristics of early hepatoblasts.
Note: The master and working banks set by BIOPREDIC allow to ensure a very high reproducibility of cell batches provided to customers.
An active proliferation rate with a doubling time of around 24h. At a seeding density of 2.7x104 cells/cm², new passages can be performed with high reproducibility every 2 weeks, up to 20 passages.
Above chart displays the representative growth kinetic of HepaRG™ cells at passage 16; progenitors were seeded at 26000/sqcm in wells of 12 well-plates in William's E medium enriched with 10%FCS
3. HepaRG™ cells can undergo a complete programme of hepatocyte differentiation
Complete differentiation programme
One week after seeding, confluent HepaRG™ cells start to commit into either hepatocyte (coloured in red in the picture above) or biliary differentiation pathways (coloured in grey).
Enriched HepaRG™ heptocytes population,
After 2 weeks, a mixed population of 2 types of cells, namely hepatocyte-like colonies surrounded by clear epithelial cells corresponding to primitive biliary cells, form a confluent monolayer which can be maintained in this stable form for several weeks in the presence of 1.7% DMSO.
Fig.A: Undifferentiated HepaRG™ cells
F-actin is represented in red
Hepatocytes colonies are recognized thanks to the formation of numerous bile canaliculi (Fig B in red), characteristic of highly polarized, mature hepatocytes.
Fig.B: Differentiated HepaRG™ cells
DNA labeling is represented in blue
However, because of the difficulty represented by selectively counting the hepatocyte competent cells and quantifying their peculiar activities with high efficiency, a specific protocol has been designed in order to increase hepatocyte selection in culture from confluent mixed HepaRG™ cell populations, thus allowing the scientists to reproduce adult human hepatocyte primary culture.
HepaRG™ cells express all main hepatic functions characterizing mature normal hepatocytes, including:
- detoxication function linked to hydrolyis and conjugation [Kanebratt KP 2008; Aninat C,2005], nitrate elimination [Hoechstra R, 2013, 2011], bile salt conjugation [Hoekstra R, 2013; Caron S. 2013]
- plasma protein production (albumin, transferrin, haptoglobin..) [Gripon P, 2002; Parent R., 2008; Klein S., 2013]
- energetic pathways linked to glucose (neoglycogenesis, glycolysis) and lipids (fatty acid) metabolism [Madec S 2011; Samanez CH., 2012; Plée-Gautier E. 2012]
- iron metabolism [Do Th., 2013].
Transferrin (in green)
CYP3A4 (green), F-actin (red)
Albumin (in green and nuclei in blue)
Asialoglycoprotein Receptor 1
Glycogen accumulation in HepaRG hepatocyte colonies after 1 week confluence with 1.7% DMSO
4. HepaRG™ expresses stem cell properties including transdifferentiation
HepaRG™ cells show a unique property of transdifferentiation through reversion to bipotent progenitor status [Cerec et al., 2007]
Both hepatocyte-like and biliary-like cells can transdifferentiate through transient bipotent hepatic progenitor status.
Transdifferentiation is presumably associated to stemness of progenitor cells.
Pure HepaRG™ hepatocytes seeded at low density
5.Bipotent progenitors transiently express stem cell properties:
0 TGF-b, 5 days
Softness and plasticity
Plasticity is also preserved in differentiated cells.
HepaRG™ cells, P16: 2 weeks differentiated cells maintained for 5 days with 2.5 ng/ml TGF-b, loose their epithelio differentiated status and undergo transition to mesenchymal cells (EMT).
Cytoskeleton reorganization is observed as well as disappearance of biliary poles.
2,5ng/ml TGF-b, 5 days
When HepaRG™ cells display bipotent proliferating progenitor phenotype, they share:
- with embryonic stem cells expression of OCT3/4,
- with oval cells expression of NCAM, ABCG2, CK18, and CK19,
- with hematopoietic stem cells expression of CD34, Thy1, Flt-3, c-Kit, IL-3R and LIF-R.
Self renewal / Senescence
Protocol of cell line maintenance
Every 2 weeks, confluent HepaRG® progenitor monolayers are detached by 3-5min incubation with trypsin solution 0.05%. Cells are collected in William’S E medium containing insulin (4µg/ml) and hydrocortisone hemysuccinate (50µM) and added with 10%FCS.
After cell counting, they are seeded in the same medium at 20x103/cm2 and placed in a CO2 incubator at 37°. Medium is renewed every 2 or 3 days thereafter. Progenitors actively grow up to 5-6 days and are highly confluent after 2 weeks.
At this stage, they can be used either for a new trypsin treatment and a new passage in order to maintain the cell line, or incubated in the same medium added with 1.7%DMSO which favours the cells undergoing complete hepatocyte differentiation programme.
Within 3-4 days, two cell types are easily recognized: the one corresponding to hepatocyte colonies and the other one corresponding to primitive biliary cells.