VRC 900: Evaluation of Tissue-Specific Immune Responses in Adults 18 Years of Age and Older

Background: \- The Vaccine Research Center (VRC) is dedicated to understanding immune responses associated with prevention and treatment of infectious diseases. To study these immune responses, researchers need to collect specimens and images from individuals who have recently had a vaccination or recovered from an infection. These specimens and images are used to study different diseases and immune responses, and can be used to investigate ways to prevent or treat different medical conditions. Objectives: \- To evaluate blood and other tissue samples for immune responses to vaccines and natural infections. Eligibility: \- Healthy volunteers at least 18 years of age who agree to donate specimens for research purposes. Design: * Participants will have clinical evaluations and will be asked to provide some of the following samples, depending on the research question being addressed. All procedures and sample donations are optional and voluntary: * Blood samples through regular blood draws (for whole blood) and apheresis (to collect specific parts of the blood such as plasma or white blood cells) * Urine, semen, saliva, or vaginal swab samples * Tissue samples or biopsy specimens * Undergo procedures such as bronchoscopy (lung and respiratory tract), gastrointestinal endoscopy (stomach and upper intestinal tract), or colonoscopy (lower intestinal tract) to obtain tissue samples * Undergo imaging studies such as positron emission tomography (PET) or computed tomography (CT) scans Duration of participation is variable depending on the research question but will usually last up to 1 year. * Participants will be compensated for participation.

* INCLUSION CRITERIA: 1. 18 years of age or older. 2. Able to provide proof of identity to the satisfaction of the study clinician completing the enrollment process. 3. Able and willing to complete the informed consent process. 4. Willing to donate specimens for storage to be used for research. EXCLUSION CRITERIA: 1. Any medical, psychiatric, occupational condition or other condition that, in the judgment of the investigator, is a contraindication to protocol participation or impairs a participant s ability to give informed consent. 2. Bleeding disorder diagnosed by a doctor (e.g., factor deficiency, coagulopathy, or platelet disorder requiring special precautions), use of anticoagulant medications for an ongoing medical condition, significant bruising or bleeding difficulties with intramuscular injections or blood draws. \[Note: Participants taking anticoagulants, such as aspirin, prophylactically may be considered on a case to case basis.\]