Infection with the Human Immunodeficiency Virus type 1 (HIV-1) triggers a strong immune response in the body, which produces antibodies when it encounters the virus. However, the majority of antibodies naturally produced by the immune system are non-neutralizing, meaning they are unable to provide protection from the virus, or to prevent the eventual onset of AIDS. Alfredo Menendez is contributing to the search for an effective vaccine that would increase the body’s production of neutralizing antibodies. He has isolated unique peptides whose molecular structures closely mimic specific neutralizing sites on the surface of the virus. Alfredo is fine tuning these mimics to develop immunogens (substances that prompt a response from the immune system). He is investigating whether use of the peptides in a vaccine prompts a focused, strong and protective immune reaction that boosts the production of HIV-neutralizing antibodies.