Hong Kong Med J 2012;18(Suppl 2):S31-6
SARS CoV subunit vaccine: antibody- mediated neutralisation and enhancement
M Jaume, MS Yip, YW Kam, CY Cheung, F Kien, A Roberts, PH Li, I Dutry, N Escriou, M Daeron, R Bruzzone, K Subbarao, JSM Peiris, B Nal, R Altmeyer
HKU-Pasteur Research Centre, Hong Kong
1. A SARS vaccine was produced based on recombinant native full-length Spike-protein trimers (triSpike) and efficient establishment of a vaccination procedure in rodents.
2. Antibody-mediated enhancement of SARS-CoV infection with anti-SARS-CoV Spike immune-serum was observed in vitro.
3. Antibody-mediated infection of SARS-CoV triggers entry into human haematopoietic cells via an Fc_R-dependent and ACE2-, pH-, cysteine-protease-independent pathways.
4. The antibody-mediated enhancement phenomenon is not a mandatory component of the humoral immune response elicited by SARS vaccines, as pure neutralising antibody only could be obtained.
5. Occurrence of immune-mediated enhancement of SARS-CoV infection raises safety concerns regarding the use of SARS-CoV vaccine in humans and enables new ways to investigate SARS pathogenesis (tropism and immune response deregulation).