The Nikon MicroscopyU confocal microscopy image gallery was created with a PCM-2000 confocal scanning system interfaced to a Nikon Eclipse E600 upright microscope. Images were recorded in successive z-axis serial sections with C-Imaging Systems software with excitation illumination provided by an argon-ion and/or a helium-neon laser.

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The lymphatic system is comprised of a series of interconnected vessels, ducts, various organs, and structures that constantly circulate a clear and watery fluid that nourishes and protects tissues throughout the body. This precious fluid and its constituents are a major component of the body's immune system and the term lymph is derived form the Latin word lympha, meaning water goddess. Generally comprised of diluted plasma and white blood cells, lymph fluid serves as a defense mechanism against viruses, bacteria, fungi, parasitic microbes, and other foreign material such as cancer cells. Unlike the primary circulatory system, the lymphatic system has no pump. Instead, the serum-like fluid flows through channels and tissues in the body during voluntary and involuntary muscle movement, which is greatly facilitated by exercise.

Lymph nodes are small soft bundles of lymphatic tissue shaped in nodules and are not usually visible or easily felt. Approximately 600 of these minute structures are located in clusters at various parts of the body such as under the armpits, behind the ears, in the groin, behind the knees and in other areas. Varying in size from microscopic to about one inch in diameter, these structures are responsible for filtering lymph fluid, producing plasma cells, and evacuating foreign material such as bacteria. Along with bone marrow, lymph nodes produce the white blood cells that form lymphocytes. One of the most studied varieties of antibody producing white blood cells are the T lymphocytes also referred to as T-cells.