FIG 1.

Association between activated NK cells and hepatoma cells and role of cytokines in augmenting C4 expression by HCV proteins. (A) NK3.3 cells were preincubated with or without 200 IU/ml rIL-2 for 24 h and cocultured for 24 h with Huh7.5 cells stably transfected with HCV core or NS5A. (B) Huh7.5 cells stably transfected with HCV core or NS5A were incubated with NK3.3 conditioned medium (NKCM) for 24 h. NKCM containing rIL-2 was collected after 24 h of culture. Cell lysates were analyzed for C4 protein by Western blotting. (C) Huh7.5 cells stably transfected with HCV core or NS5A were cocultured separately with rIL-2-activated NK3.3 cells in a transwell chamber for 24 h. Hepatoma cells were lysed and C4 expression status analyzed by Western blotting.