Core C: Clinical Core ABSTRACT The Penn CFAR Clinical Core (Core C) forms the central nexus for patient-oriented interdisciplinary research conducted by CFAR investigators to advance knowledge that will improve the lives of people living with HIV (PWH) and those at risk of HIV acquisition, including adults, adolescents (behaviorally-acquired), and children (perinatally-acquired). Core C's overarching objectives are to: 1) catalyze basic, translational, clinical, epidemiologic, behavioral, and implementation science research by providing investigators with a broad range of data and clinical materials from PWH and those at risk, including biomedical and behavioral data, and stored and freshly-acquired specimens; 2) support recruitment of PWH or individuals at-risk into clinical studies; 3) provide advice, consultation, and expertise in utilization of Core services and study development; and 4) provide clinical research education, training, and mentorship. Core C is led by Drs. Vincent Lo Re (Director), William Short and Sarah Wood (Co-Directors), and Ian Frank (Core Investigator). Over the current funding period, Core C has contributed to >175 research projects with important discoveries in HIV reservoirs, clinical trials, comorbidities and other HIV/AIDS research priority areas. Core C achieves its mission through essential services including: 1) participant recruitment and data acquisition via an Adult/Adolescent Database comprised of 3,394 PWH cared for at one adolescent and four adult HIV practices, a Pediatric Database with longitudinal data on over 100 perinatally-infected children, and a Prevention Database containing over 100 individuals at risk of HIV who underwent screening for HIV prevention clinical trials; 2) Patient material via the CFAR Adult/Adolescent & Pediatric Specimen Repositories linked to the Databases, and by procurement of fresh material, including blood, apheresis products, genital secretions, gastrointestinal tissue, and lymph via cannulation of the thoracic duct; 3) Consultation on study design and execution of studies; and 4) Educational activities and mentorship for trainees and junior faculty to advance their research and enhance success in clinical/translational HIV research. The Clinical Core's services, leadership, and expertise have continued to evolve over the current funding cycle in response to emerging opportunities and priorities identified through proactive strategic planning, user feedback, and input from internal and external advisors. The Core fosters research aligned with NIH and Penn CFAR research priorities as well as those of the Penn CFAR Scientific Working Groups, which in the upcoming cycle will be “HIV Single Cell Reservoirs and Immunology” and “HIV Communication and Policy” SWGs. Looking ahead, several innovations will be featured and expanded in the coming funding cycle, including access to lymphoid tissues relevant to understanding HIV reservoirs and virus persistence, immunologic control, and ...