Response of human liver tissue to innate immune stimuli

Precision-cut human liver slice cultures (PCLS) has become an important alternative immunological platform in preclinical testing. To further evaluate the capacity of PCLS, we investigated the innate immune response to TLR3 agonist (poly-I:C) and TLR4 agonist (LPS) with the normal and pathological liver tissue. Pathological liver tissue was obtained from patients with active chronic HCV infection, and patients with former chronic HCV infection cured by recent Direct-Acting Antiviral (DAA) drug therapy. We found that hepatic innate immunity was not suppressed but enhanced in the HCV-infected tissue, compared with the healthy controls. Furthermore, despite recent HCV elimination, DAA-cured liver tissue manifested ongoing abnormalities in liver immunity. Sustained abnormal immune gene expression in DAA-cured samples were identified from direct ex vivo measurements and with TLR3 and TLR4 stimulation assays. Those genes that were up-regulated in chronic HCV-infected liver tissue were enriched in expression in the liver non-parenchymal cell compartment. These results demonstrated the utility of PCLS in studying the liver pathology and innate immunity.