The study, which represents the first published work on the development of a SARS vaccine and comes only a few months after the SARS coronavirus was identified and its genome was sequenced, is reported in a fast track research letter in the Dec. 6 issue of The Lancet.
"It is our hope that this research will lead to a protective vaccine against SARS," stated project leader Andrea Gambotto, M.D., from the departments of surgery and medicine, division of infectious diseases and the Molecular Medicine Institute (MMI) at the University of Pittsburgh School of Medicine.
In the study, researchers immunized six rhesus macaques intramuscularly with a combination of three SARS-CoV vectors. Two additional macaques were immunized with the same amount of empty adenoviral vector and served as controls. After 28 days, the animals received a second vaccination. Six weeks after vaccination, T-cells and antibodies against SARS were detected in all six of the immunized animals, but not in either of the control animals. The intensity of the response varied among animals but was generally largest after the booster vaccination, according to the Pittsburgh researchers. Serum samples from the vaccinated animals, but not from the controls, showed strong neutralizing capacity against SARS-CoV.
"From a scientific perspective, several points are important. We obtained the recombinant vaccine by engineering a common cold virus to express the SARS coronavirus antigens. This is a successful strategy that we are exploring for other infectious diseases such as HIV," said
Contact: Frank Raczkiewicz
University of Pittsburgh Medical Center