Human hepatic cell line 5: In-vitro model for hepatic immunobiology

Background: Hepatocellular carcinoma (HCC) remains a major global health burden, partly due to the lack of physiologically relevant in vitro models that accurately recapitulate early host-virus interactions and immune responses. Human Hepatocyte Line 5 (HHL-5) is an immortalized hepatocyte cell line that retains key liver-specific functions. This study aimed to characterize the phenotypic, genetic, and metabolic features of HHL-5 cells and evaluate their suitability as a non-cancerous hepatic model, in comparison with the HCC cell line HepG2. Methods and results: Morphological and phenotypic assessment of cells showed smaller cell and nuclear areas and slower proliferation with markedly longer doubling time of HHL-5 cells than HepG2 cells. Genomic analyses using whole-exome sequencing revealed enrichment of immune-related pathways in HHL-5 cells, including antigen processing and presentation, whereas HepG2 cells showed predominance of DNA replication pathways. Metabolomic profiling of cells by nuclear magnetic resonance spectroscopy showed hepatocyte-like oxidative profiles of HHL-5 cells, in contrast to the glycolytic phenotypes of HepG2 cells. Moreover, Western blotting for selected proteins showed reduced expression of oncogenic and stress-response markers, including c-Myc, pSTAT3, pNrf2, and select cytochrome P450 enzymes. Conclusion: Our findings support HHL-5 cells as a robust non-cancerous in vitro model for investigating liver diseases, viral infection, and early events in hepatocarcinogenesis. Clinical Trial Registration: Not applicable.