Maintenance of primary murine hepatocyte functions in multicomponent polymer capsules - in vitro cryopreservation studies

Background/Aims: The potential of a new encapsulation system has been evalu ated as an artificial housing for liver cells. Methods: Murine hepatocytes were encapsulated in specially designed multico mponent capsules formed by polyelectrolyte complexation of sodium alginate, cellulose sulphate and poly(methylene-co-guanidine) hydrochloride, the per meability of which has previously been characterised. Results: We demonstrate here the absence of cytotoxicity and the excellent biocompatibility of these capsules towards primary culture of murine hepato cytes. Experimental results demonstrated that the encapsulated hepatocytes retained their specific functions - transaminase activity, urea synthesis a nd protein secretion - over the first 4 days of culture in minimum medium. The cryopreservation of encapsulated hepatocytes, for periods of up to 4 mo nths, did not alter their functional capacities, as no major differences we re observed between unfrozen and frozen encapsulated cells for the function s tested, Conclusions: Because of the absence of cytotoxicity, and the ease of handli ng and cryopreservation, while maintaining liver specific functions, the de scribed system appears to be valuable for murine liver cell encapsulation, It is also a promising tool for fundamental research into drug metabolism, intercellular regulation, metabolic pathways, and the establishment of bank s for the supply and storage of murine hepatocytes. (C) 2001 European Association for the Study of the Liver. Published by Else vier Science B.V. All rights reserved.