Physicochemical characteristics of hepatic stimulatory factor prepared from cell free supernatant of hepatocyte cultures.

We previously reported that the cell free supernatant of hepatocyte cultures contained a hepatic stimulatory factor, which increases survival time and stimulates liver regeneration in the galactosamine induced fulminant hepatic failure animal model. When hepatocytes were microencapsulated in an alginate matrix, the cell free supernatant outside the microcapsuled lacked the above stimulatory effects. However, the cell free content of microcapsules was able to increase both survival time and incorporation of 3H-thymidine in our animal model. This hepatic stimulatory factor has a molecular weight greater than albumin because alginate microcapsules allow the penetration of albumin but not the hepatic stimulatory factor. In this paper we report the molecular weight study and some other physiochemical characteristics of this factor. Using Sephacryl gel chromatography we showed that this factor has a molecular weight of over 110,000 D. This factor loses its hepatic stimulatory effect after heat or trypsin treatment. Although its elution profile on Sephacryl gel does not change after such treatments.