Hepatitis C virus-like particles synthesized in insect cells as a potential vaccine candidate

Background & Aims: Hepatitis C virus (HCV) is a leading cause of chronic he patitis in the world. Successful vaccine development is crucial in controll ing global HCV infection. We have previously described the generation of HC V-like particles (HCV-LPs) in insect cells using a recombinant baculovirus containing the complementary DNA of the HCV structural proteins. These HCV- LPs had similar morphological and biophysical properties as the putative vi rions. In this study, we analyzed the structural features, antigenic compos ition, seroreactivity, and immunogenicity of purified HCV-LPs. Methods: HCV -LPs were analyzed by electron microscopy and antibody immunolabeling and p recipitation, An enzyme-linked immunosorbent assay (ELISA) using HCV-LPs wa s developed. The humoral response to HCV-LPs in mice was studies by core an d envelope ELISAs, Western immunoblotting, and immunofluorescence. Results: Structural and antigenic compositions of HCV-LPs were shown to be similar to those of putative HCV virions. Using the HCV-LP ELISA, high-titer anti-H CV antibodies were detected in individuals infected with various HCV genoty pes, In vivo, HCV-LPs elicited a humoral response broadly directed against HCV structural proteins, Conclusions: HCV-LPs resemble HCV virions and are capable of inducing a humoral response targeted against various regions of HCV structural proteins, suggesting that HCV-LPs may be promising as a pote ntial vaccine candidate.