Quantitative and qualitative analysis of immune response to vaccination is a critical component for testing new vaccines in preparation for a bioterrorist attack. In addition, early detection and diagnosis of an infectious agent is crucial for treatment and crisis management in the event of a bioterrorist attack by a new/unknown pathogen. Similarly, identification of new proteins involved in pathogen infection and host-cell responses to infection are also needed for biodefense preparedness. Recent advances in mass spectrometry-based proteomic methods can be applied to achieve these goals, and is a major focus of this proposal. A strong translational research and clinical team has been assembled to combine new proteomic and bioinformatics tools with existing immunological assays, both influenza vaccine platforms, and archived infected serum samples. Our central hypothesis is that immune responses to vaccination can be quantified by proteomic profiling of serum (or other clinical fluids), and that the host response to different infectious agents are unique and can be 'fingerprinted' by proteomics. We propose to use influenza virus, a Category C bioterrorism pathogen, as a model agent to develop a SELDI mass spectrometry proteomic profiling system for monitoring vaccine response and early detection/diagnosis of infection. The ultimate goal of our study is to reduce the morbidity and mortality of influenza from natural and potential bioterrorism infections by improving vaccine efficacy and early diagnosis. Two experimental approaches will be taken. One is to use proteomic profiling of pre- and post influenza vaccination serum obtained from young and elderly patient cohorts to identify surrogate biomarkers reflective of the immune response. For comparison, a similar young adult cohort will receive the live-virus intranasal FluMist vaccine. These protein profile differences will be correlated with T cell activation and antibody responses to vaccination. The second approach will compare proteomic profiles from serum and nasal swabs of acutely infected influenza patients with control and RSV-infected patients. Potential biomarker proteins identified in all analyzed samples will be isolated and sequenced by mass spectrometry. These studies could lead to the development of crucial new paradigms for detection, diagnosis and vaccination strategies necessary to increase our national biodefense preparedness against viral pathogens. ? ?