Vaccines and Immunization

Biography

Biography: Ming-Fu Chang

Abstract

Middle East respiratory syndrome (MERS), an atypical variant of pneumonia, emerged in 2012 and spread to 27 countries. Until 2019, the MERS epidemic is still considered as a significant threat to human beings as its mortality rate is around 36%. MERS coronavirus (MERS-CoV), a novel lineage C betacoronavirus classified as a member of the Coronaviridae family was identified as the causative pathogen of MERS. The structural proteins comprise a spike glycoprotein (S), a membrane glycoprotein (M), a small envelope protein (E), and a nucleocapsid protein. hDPP4 was identified to be the functional receptor for MERS-CoV. To date, no drugs and vaccines have been clinically approved to control MERS-CoV infection. One of the most promising tools in vaccine development is the use of recombinant-based virus-like particles (VLPs). VLPs are multiprotein structures closely resembling natural virions and lack viral genetic materials. In addition, VLPs display intact and biochemically active antigens on their surface and thus, show high immunogenicity and antigenicity. Importantly, VLPs interact with the host immune system inducing humoral and cellular responses similarly to the native pathogen. In this study, MERS-CoV VLPs containing S, M, and E proteins were produced by baculovirus expression system. Results showed that MERS-CoV VLPs with diameters approximately 100 nm were detected by electron microscopy, and spike protein appeared around the spherical particles. Immunofluorescence assay demonstrated that colocalization of the spike protein-incorporated VLPs with hDPP4. In addition, BALB/c mice were vaccinated with MERS-CoV VLPs that could induce neutralizing antibodies. The protection assay is ongoing.