title: The prevalence and purification of hepatoproliferin: a liver regeneration factor from rat hepatocytes.
abstract: Hepatoproliferin (HPF), a liver regeneration factor that was able to augment the growth of hepatocytes in the presence of EGF, was produced by young rat livers and hepatectomized adult livers (70%), but not by adult intact livers. Therefore only growing and regenerating livers produce HPF. This growth factor was purified into two homogeneous bioactive species having different single SDS-PAGE bands at 18.5 and 14 kDa, and different single pI-bands at pH 4.3 and 8.7, respectively. HPF was synthesized de novo by hepatocytes in the liver as shown by the in vivo incorporation of radiolabeled 35S-sulfate and 14C/3H-glucosamine. This radioactive HPF was secreted ex vivo by hepatocytes, probably to act as an autocrinal hepatomitogen since 90% was found in the growth medium. HPF was neither a classical peptido-mitogen nor a heparin binding growth factor, but a liver-originated non-proteinaceous factor, which probably contains sulfonated saccharides such as glucosamine sulfate. HPF was neither a polyglycan nor a glycopeptide nor a peptidoglycan.
authors.affiliation: MRF Biochemistry Laboratory, Department of Surgery, University of the Witwatersrand, 7 York Road, Johannesburg, Parktown ZA 2193, South Africa. oosthuizenmmj@medicine.wits.ac.za
authors.forename: Mathys M J
authors.initials: MM
authors.lastname: Oosthuizen
authors.forename: Hugo
authors.initials: H
authors.lastname: Lambrechts
mesh_terms: D000596:Amino Acids / Q000378:metabolism; D000818:Animals; D002478:Cells, Cultured; D002845:Chromatography; D006023:Glycoproteins / Q000378:metabolism*; D006133:Growth Substances / Q000302:isolation & purification* / Q000378:metabolism*; D006498:Hepatectomy; D022781:Hepatocytes / Q000166:cytology / Q000378:metabolism*; D006595:Hexosamines; D006801:Humans; D008099:Liver / Q000166:cytology / Q000502:physiology*; D008115:Liver Regeneration / Q000502:physiology*; D008297:Male; D011868:Radioisotopes / Q000378:metabolism; D011869:Radioligand Assay; D051381:Rats; D017207:Rats, Sprague-Dawley
chemical_list: D000596:Amino Acids; D006023:Glycoproteins; D006133:Growth Substances; D006595:Hexosamines; D011868:Radioisotopes; C492881:hepatoproliferin, rat