Prior to testing in humans, vaccine candidates are developed and tested extensively by researchers in the laboratory and then in different animal models. Researchers fully characterize the engineered vaccine in the laboratory: whether it is a viral vector, protein subunit, or DNA-based vaccine that will be used to present HIV protein to the immune system. To try to gauge the safety and immunogenicity of a vaccine candidate, research is then done in animal models. Usually the vaccine candidate will first be tested in mice and then in non-human primates.
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