Long term cultivation of functionally active normal human adult hepatocytes.

Monolayer cultures were obtained from human liver explants. The cells, which extend in all directions, are trypsinized then collected by differential centrifugation and incubated at 38 degrees 5. The oldest culture is 12 month-old. Albumin and alpha 1-antitrypsin are constantly detected and measured in the supernatant by radioimmunoassay. The liver specific protein is always characterized by immunofluorescent staining on the surfaces of the cultivated cells.