A human Lymphocyte cell. These natural killer Lymphocyte cells are a part of the immune system and play a major role in defending the host from both tumors and virally-infected cells. Photograph by David Scharf.
Infinite Delight - An electron microscope catches the immune system blooming into action. A white blood cell (red) wraps itself around a mycobacterium tuberculosis, the causative agent of most cases of tuberculosis.
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