This Shared Instrumentation Grant requests a Biacore3000 instrument to perform real-time surface plasmon resonance (SPR) analyses of receptor ligand binding interactions. The core user group consists of five full-time faculty members from the Departments of Medicine (Lehrer, Ganz, Cole), Pathology (Baum, Ganz), Microbiology, Immunology and Molecular Genetics (Lee), and Molecular Biology Institute (Baum, Lehrer). Biamolecular binding interactions are central to the research efforts of all of these investigators, and all will benefit from the exceptional sensitivity and high throughput capacity of the requested instrument. Because three of the users (Baum, Lee and Lehrer) study the interactions of peptides and proteins with carbohydrates and sugars, only the Biacore3000 instrument combines a) the sensitivity necessary to detect oligosaccharide binding, with b) high throughput capacity, and c) the ability to recover analyte samples with minimal dilution. The investigators are committed to sharing the instrument and will be proactive in making it available for other users. This will include providing access to the services of two highly skilled operators for occasional or new users of the instrument. The benefits and health relatedness of the proposal are that it will facilitate accomplishing the research goals of the ten NIH grants or proposals listed in Table 1 within. These include the development of new agents and approaches to prevent and treat infections caused by HIV-1 and other viral pathogens, and fundamental issues related to cell targeting and survival.