Two
cell lines, PICM-19H and PICM-19B, were derived from the bipotent ARS-PICM-19
pig liver stem cell line and assessed for their potential application in
artificial liver devices. The study included assessments of growth rate and
cell density in culture, morphological features, and
hepatocyte detoxification functions, i.e., inducible CYP450 activity,
ammonia clearance, and
urea production. The PICM-19H cells contain numerous mitochondria,
Golgi apparatus, smooth and rough
endoplasmic reticulum, vesicular bodies and occasional lipid vacuoles. PICM-19H cells display inducible CYP450 activity, clear
ammonia, and produce
urea in a
glutamine-
free medium. Ultrastructural analysis of the PICM-19B monolayers show that the roughly cuboidal cells display basal-apical polarization and are joined by
tight junction-like complexes. Other
ultrastructure features are similar to those of PICM-19H cells except that they possess numerous
cell bodies resembling
mucus vacuoles. The PICM-19B cells possess relatively high levels of GGT activity, but retain some inducible CYP450 activity, and some
ammonia clearance and
urea synthesis ability. These data indicate that both cell lines, either together or alone, may be useful as the cellular substrate for an
artificial liver device.
In vitro models of the liver are needed to replace animal models for the
rapid assessment of
drug biotransformation and
toxicity. A unipotent porcine
stem cell line PICM-19H differentiates exclusively into hepatocytes and can be induced to express CYP450 enzymes. These cells have many activities associated with
xenobiotic phase I and phase II
metabolism lacking in other liver cell lines. The PICM-19H cell line was also compared to the tumor-derived human HepG2 C3A cell line and to primary cultures of adult porcine hepatocytes. The results demonstrate the potential for the use of PICM-19H cells in
drug biotransformation and
toxicity testing and further support their use in
artificial liver device technology.