PROJECT SUMMARY The specific aim of the Immunopathology Core Program (IPC) is to provide pathology and immunology support to COBRE and other Oklahoma Center for Respiratory and Infectious Diseases (OCRID) investigators. Services provided by the IPC include a broad range of pathology support including gross necropsy and tissue collection, tissue processing, sectioning of either frozen or paraffin-embedded tissues, routine and special stains, immunohistochemistry (IHC), immunofluorescence (IFC), and coordination of ancillary services (clinical pathology, bacteriology, virology, toxicology). Immune responses important in the development of disease are characterized by evaluation of cell- mediated immunity (ELISPOT, flow cytometry for intracellular IFNγ) and phenotypic identification of inflammatory cells within lesions (IFC, IHC, flow cytometry). The IPC will also coordinate with the Animal Models Core (AMC) and Molecular Biology Core (MBC) to assist investigators with humoral immunity (serology, ELISA) and quantitation of cytokine gene expression (real-time PCR) respectively. To achieve this aim, the IPC is staffed by three board-certified pathologists with experience in animal models and respiratory/infectious disease research and an experienced, extensively cross-trained technician. The IPC has the resources in place to serve as the foundation and a strong institutional commitment to ensure development of the IPC into a self-sustaining facility integral to the research infrastructure of OCRID.