TNF and steatosis: In one study, mature human hepatocytes and adipocytes differentiated from primary human preadipocytes were cultured as monolayers.[124] Despite the rapid decline in phenotypes in monolayer culture, this model successfully recapitulated in vivo cytokine‐driven lipotoxicity evidenced by the observation that TNFα did not induce steatosis in hepatocyte monocultures but did so robustly in the presence of adipocytes.