Project Summary/Abstract: We are requesting funds to purchase a Hitachi 7800 transmission electron microscope (TEM) for the Electron Microscopy Core Facility (EMCF) at CU Anschutz Medical Campus in Denver (Aurora), Colorado. The EMCF, managed by the Department of Cell and Developmental Biology, is a campus-wide, institutionally supported fee for service facility that provides electron microscopy services for basic and clinical science investigators at CU Anschutz as well as several investigators from neighboring institutions. Currently, the core has only one TEM, a twenty-year-old Thermo Fisher Tecnai T12, which is no longer state of the art, is frequently out of service due to failing components, is difficult to maintain and whose service contract will end December 2025. We need to replace this aged TEM with a Hitachi 7800, which is also a 120 kV TEM, with a high contrast optic design ideal for biological samples. The Hitachi 7800 has a proven robust hardware system and is especially designed for easy and fast sample exchange. It has user-friendly software with unique features such as image rotation, montaging, and pre-irradiation without the need to install secondary software. Acquisition of the new microscope will greatly facilitate the health-related research of the laboratories listed in this application, as well as many other laboratories who use the EMCF in support of their NIH funded research. Among other projects, the requested microscope will be used to study important questions in diseases such as: early steps of HIV-1 infection, Epidermolysis Bullosa disease, kidney disease, regulation of Staphylococcus aureus colonization and disease, demyelination and remyelination, formation and function of meninges, and barriers to drug delivery.