FIG. 7.

Isolation of virus-like particles from insect cells infected with recombinant baculovirus containing cDNA encoding the structural HCV proteins. (A) Western blot analysis of the production of core protein in Sf9 cells by using MAb ACAP27. Results for extracts from recombinant baculovirus-infected cells (lane 1) and extracts from uninfected cells (lane 2) are shown. (B) Purification of nucleocapsid-like particles from lysed cells on a CsCl gradient. HCV core antigen (Ag) was detected by ELISA, and virus particles from the core antigen peak were visualized by electron microscopy (Fig. 3G and H). O.D., optical density.