Figure 1. Metabolic fingerprint of HCV infection in oxygenated cocultures of primary human hepatocytes.

(a) Schematic of the experimental design. Primary human hepatocytes were cocultured with lung endothelial cells under high-oxygen, serum-free conditions. Cultures were infected with cell culture variants of HCV (JFH-1 or JC1), and their metabolic function was tracked for 10 d in culture. Once metabolism had restabilized, we carried out metabolic flux analysis to identify differentially activated metabolic pathways. Transcriptional regulatory analysis was used to identify the upstream regulators by their differentially activated target genes in each metabolic pathway. (b) Phase images of naive and JFH-1-infected cultures on day 10 post-infection. Numerous droplets are seen in infected cells. (c) Fluorescent image of JC1-RFP-infected culture counterstained for neutral lipids on day 10 post-infection. (d) Top, production of HCV RNA and infectious virus titer as a function of time post-infection, normalized to a culture of Huh7.5.1 infected with JFH-1 (n = 3). Bottom, intracellular levels of HCV core protein, HCV RNA and triglycerides on day 10 post-infection (n = 3). (e) Changes in glucose uptake and in production of urea, albumin, lactate, ketone bodies and triglycerides in naive and HCV-infected primary hepatocytes. *P < 0.05; **P < 0.001; n refers to the number of experimental replicates.