Clinical Cohort Core Summary An efficient, reliable and comprehensive source of clinical data and biological specimens is essential to the design and implementation of the Tulane University COVID Antibody and Immunity Network (TUCAIN). U54 Center. The Clinical Cohort Core will fill this need by bringing together outstanding investigators who are currently leading a diversity of patient cohorts from across the lifespan that are highly relevant to this proposal. The overall goal of this Core is to develop and maintain a diverse set of cohorts made up of human subjects from childhood to the elderly and to longitudinally collect clinical data and biological specimens required to complete both TUCAIN and SeroNet activities. The Core will support the Immunoassay Core as well as both Projects 1 & 2 by providing a centralized team for patient recruitment, demographic and clinical data collection and serial sample collection and processing. In this role, the Core will also be responsible for maintaining all ethics approvals as well as maintaining electronic sample logs and providing samples and clinical data to Projects 1 & 2 as needed. The Clinical Cohort Core will be responsible for the following Specific Aims: (1) Coordinate the safe and efficient collection of serial samples from enrolled subjects. By centralizing sample collection and processing as well as data collection, we will enhance the rigor and reproducibility of all work done by this Center. (2) Leverage existing COVID-19 cohorts. Several TUCAIN investigators have already established cohorts of COVID-19 patients recruited during hospitalization for their acute infection. Samples and clinical collected as part of these studies will be made available to TUCAIN and SeroNet. (3) Build on existing cohorts of COVID-19 survivors recruited from the community. TUCAIN investigators have been at the forefront of the COVID-19 response and have well established cohorts of subjects with laboratory-confirmed or perceived infection. Data and biological samples from these cohorts will be available to TUCAIN and SeroNet. (4) Leverage existing funds supporting a pediatric asthma cohort to perform syndromic surveillance. We will utilize samples collected as part of an existing cohort of children. By following them for at least three years, we will be able to identify changes in the serological response over time. (5) Establish a large cohort of patients with solid and hematologic tumors. This cohort will serve as a critical resource for understanding the impact of malignancies and chemotherapy on the serological response to SARS-CoV-2 infection. These valuable resources will allow investigators at Tulane and the wider scientific community to pursue a multitude of studies on the serological response to SARS-CoV-2. Successful development and management of these cohorts will significantly enhance the research potential of the Immunoassay Core and Projects 1 & 2 as well as the larger goals of SeroNet.