Identification of Two Neutralizing Regions on the Severe Acute Respiratory Syndrome Coronavirus Spike Glycoprotein Produced from the Mammalian Expression System

Abstract

The Spike (S) protein of the severe acute respiratory syndrome-associated coronavirus (SARS-CoV) plays important roles in viral pathogenesis and potentially in the development of an effective vaccine against this virulent infectious disease. In this study, the codon-optimized S gene of SARS-CoV was synthesized to construct DNA vaccine plasmids expressing either the full-length or segments of the S protein. High titer S-specific immunoglobulin G antibody responses were elicited in rabbits immunized with DNA against various segments of the S protein. Two neutralizing domains were identified on the S protein, one at the N terminus (Ser12-Thr535) and the other near the C terminus (Arg797-Ile1192).