The invention features a liver cell culture comprising hepatocytes that have increased detoxification enzyme activity when isolated from a liver of a donor that had been administered at least one induction agent prior isolation of hepatocyte cells. The induced hepatocytes are used in a bioreactor and cultured to produce hepatocyte cell products or metabolize toxins added to the culture. The bioreactor is, or is an integral part of, a liver assist device used to treat a patient in need of liver assist.