In order to study the regulation of HBV-derived epitope presentation in a more controlled in vitro system, we established an infection system to mimic acute HBV infection (arbitrarily defined as events occurring 12 h to 7 days postinfection [p.i.]) using PHH and HepG2-hNTCP-A3 cells (Fig. 2a) The HLA class I compatibility between the target and our reagents (HLA-A*02:01-restricted HBc18-27 and HBs183-91-specific CD8+ T cell clones) and the two TCR-like antibodies (Ab-A2-HBc18 and Ab-A2-HBs183) was retained by using HLA-A*02:01+ PHH while HepG2-hNTCP-A3 cells are HLA-A*02:01+. The gene discussed is HLA-A; the disease is infection.