HCV is a member of the Flaviviridae family. Its 9.6-kb RNA genome carries a long open reading frame. This frame is co- and post-translationally cleaved by cellular and viral proteases [23] into structural

proteins (core, E1, and E2) and nonstructural proteins (p7, NS2, NS3, NS4A, NS4B, NS5A, and NS5B). Core, E1, and E2, the structural proteins, constitute the major viral components of the viral particles, while the nonstructural proteins are required at multiple levels of the virus life cycle, including viral RNA replication [24] and infectious-particle assembly [25]. The single open reading frame is located between two untranslated regions (UTRs), the 5’ UTR and the 3’ UTR, which contain RNA sequences essential for RNA translation and replication, respectively [26–28]. Falcon et al. observed the presence of AR-13324 chemical structure enveloped VLPs with an average diameter of

65 nm in the JIB04 purchase cytoplasm and inside cytoplasmic vesicles in HCV-infected patient liver tissue. Smaller enveloped VLPs with diameters ranging from 30 to 55 nm were also localized in the cytoplasm of hepatocytes. All of these VLPs were clearly composed of an inner electron-dense core-like particle surrounded by an envelope. In addition, large numbers of unenveloped BTK inhibitor VLPs resembling nucleocapsid-like structures of 30 nm in diameter were detected mainly in the cytoplasm and also in the ER membranes [29]. Similarly, Chua et al. constructed HCV virus-like particles using a recombinant adenovirus

containing encoding the Tau-protein kinase HCV structural proteins (core, E1, and E2) of HCV 77H, genotype 1a [30]. The baculovirus/insect cell system has been used extensively for the production of VLPs to study viral assembly processes in the absence of infectious viruses, produce antigens for immunization and proteins for diagnostic assays and for gene transfer [31–34]. In this study, various fusion proteins of HCV core, peptides RGD (Arg-Gly-Asp), and IFN-α2a fragments (His-H1, His-H2, His-H3, and His-H4) were successfully expressed via the baculovirus expression system and purified by Ni-NTA agarose. Transcriptional and translational analysis results show that transcriptional levels and expression levels of vAcH1 and vAcH2 are higher than the vAcH3 and vAcH4. His-H1, His-H2, His-H3, and His-H4 all can specifically bind with MDA-MB231. The binding activity of His-H1 and His-H2 is stronger than His-H3 and His-H4 (Figure 1E). The binding activity of His-H1 and His-H2 on MDA-MB231 increased with protein concentration (from 0.5 to 10 μM). At the same time, HCV core, peptide RGD, and IFN-α2a fragments were expressed by baculovirus expression system and assembled into VLPs.