The bacteria Enteropathogenic E. coli (EPEC) is a major cause of infantile diarrhea, killing an estimated 100,000 children every year. (The bacteria is also closely related to enterohemorrhagic E. coli 0157:H7, which causes hamburger disease.) Most bacteria attach to existing proteins on host cells to cause disease. EPEC inserts its own protein into host cells and then attaches itself to the protein. Annick Gauthier is studying a specialized transport system—called a type III secretion system—that is believed to deliver this necessary protein from the EPEC bacteria into host cells. Her goal is to understand this fundamental mechanism, which is found only in disease-causing bacteria. Learning how this system works could provide targets for both vaccine and antibiotic development that would harm only the disease causing E. coli, and not the healthy bacteria that normally reside in the intestine.
Year: 2002
Peptide epitopes for the HIV-1 neutralizing antibodies 2F5 and 2G12 as anti HIV-1 vaccine candidates
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.
AMPR receptor trafficking and membrane surface expression in models of cerebral ischemia (stroke)
A common consequence of stroke or heart attack is brain cell death. Studies indicate that an increase in AMPA, a type of neurotransmitter receptor on the surface of brain cells, may be one of the critical causes leading to brain cell death during a stroke. Yitao Liu is investigating the mechanisms that lead to an increase of AMPA receptors on the surface of brain cells. He hopes his work contributes to a better understanding of how brain cells die following a stroke and suggest ways to limit the activity of AMPA receptors and decrease brain cell death.