Effects of IL-12 and IL-18 on HBcAg-specific cytokine production by CD4 T lymphocytes of children with chronic hepatitis B infection

The influence of IL-12 and IL-18 was evaluated on hepatitis B core antigen (HBcAg)-specific cytokine production (IFN-γ, IL-4, IL-5 and IL-10) by CD4 T lymphocytes isolated from peripheral blood of children with chronic hepatitis B. CD4 T cells were isolated from peripheral blood of 20 children with chronic active hepatitis B, cultured for 48 h in presence of rHBcAg and of co-stimulators, IL-12 or IL-18 or IL-12 + IL-18 or in their absence (control). Production of studied cytokines was examined using the ELISPOT assay. Co-stimulation with IL-12 or IL-18 was found to significantly augment the HBcAg-specific secretion of IFN-γ. However, the most pronounced stimulatory effect was observed in the presence of IL-12 + IL-18 and resulted in peak levels of IFN-γ production. The obtained results allowed concluding that the anti-HBV activity of Th1 lymphocytes is strongly induced by IL-12 + IL-18 and may contribute to viral clearance in children with chronic hepatitis B infection.