Our bodies have enemies, which we are unable to see and may not even be aware to exist. We also have an army that expertly protects us against all forms of external threat and is constantly on guard: our “immune system!”
The immune system, which is made up of special cells, proteins, tissues, and organs, defends people against germs and microorganisms every day.
The immune system is a network of cells, tissues, and organs that work together to defend the body against attacks by “foreign” invaders.
Bone marrow, the soft tissue in the hollow center of bones, is the ultimate source of all blood cells, including lymphocytes. The thymus is a lymphoid organ that lies behind the breastbone.
Lymph nodes, which are located in many parts of the body, are lymphoid tissues that contain numerous specialized structures: T cells from the thymus concentrate in the paracortex; B cells develop in and around the germinal centers; Plasma cells occur in the medulla.