561. Recombinant Adenovirus Carrying Spike Gene Induces Effective Humoral and Cellular Immunity Against SARS-CoV in Rats

Abstract

Severe acute respiratory syndrome (SARS) is life threatening contagious disease caused by a novel coronavirus, named SARS-associated coronavirus (SARS-CoV). Now there still aren't specific effective medicine and remedy to prevent or cure SARS. The patients suffering SARS are always administered heteropathy or conservative therapeutics. In order to prevent SARS, it may be necessary to develop vaccines against SARS-CoV. Inactivated SARS-CoV by irradiating is the most facile and convenient vaccine, but inactivated vaccine presumably possess a potential risk which results in the infection of the vaccinated, e.g. inactivated measles virus vaccine. Therefore, it could be a promising strategy to develop DNA vaccine. S protein is responsible for recognizing and binding its receptor of host cells, and directing the fusion between viral and cell membranes. We constructed recombinant adenoviruses carrying S1 fragment (Ad-S1) or S1 and S2 fragment(Ad-S12) of spike gene of SARS-CoV strain BJ01. We have investigated the ability of these recombinant adenoviruses to induce SARS-CoV virus-specific immunity in Wistar rats. Rats were immunized subcutaneously or through airway with the two recombinant adenoviruses respectively at day 0, 7 and 21. Preliminary results showed that all of vaccinated animals generated the antibodies and T-cell responses against SARS-CoV spike protein, and showed strong neutralizing antibody responses to SARS-CoV infection in vitro. These results indicate that adenoviral-based vaccine carrying spike gene fragment is able to induce strong SARS-CoV-specific immune responses in rats, and promising for development of a protective vaccine against the infection of SARS-CoV.