Background: The Laboratory of Immune System Biology (LISB) works with other labs at the National Institutes of Health. They study how parts of living things come together to make a whole. LISB designs and improves research tests on human samples like blood and cells. In order to do its work, LISB needs to have a lot of these samples available.

Objective: To collect biological specimens to use for designing and improving research tests. Specimens include blood, stool, saliva, and skin/mucosal swabs.

Eligibility: Healthy people ages 3-80

Design: Participants will be screened with an interview about their general health and their medical history. They will have a physical exam and blood tests. If the results of the screening are normal, participants will be asked to give one or more of these samples: Blood will be drawn from an arm vein with a needle and syringe. Mucus and skin will be collected by rubbing the area with a cotton swab. The areas may include the top of the tongue, inside the cheek, nostrils, behind the ear, elbow pit, or vagina. Participants will spit into a tube to collect saliva. Participants will pass stool into a plastic container that fits in the toilet under the seat. They will get sampling kits and instructions. Over the next 5 years, if more samples are needed, participants will be contacted to set up another visit to the NIH. These visits will each take about 1 hour. About every 2 years, when participants come to NIH for a visit, extra blood will be collected. It will be tested for HIV and hepatitis B and C.