Cryopreserved human hepatocyte lots from TRL are of very high quality as compared to other vendors. They attach to collagen-coated tissue culture surfaces within a few hours, form beautiful confluent monolayers, have bile canaliculi and are contamination free. Furthermore, customer service from TRL is the best I have seen in a while as compared to other vendors. We use their hepatocytes for drug metabolism, drug-induced liver toxicity and other applications. Their prices are unbeatable as well.