Page 67 - The Miracle in the Immune System
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Cells On Duty In The System      65

          digest all of them, they expand in size. When distended
          by the antigens, the cells burst, causing a liquid sub-
          stance (pus) to overflow. This does not mean that the
          war is lost. So far, the eater cells have just met the mi-
          crobes, which have still many tougher barriers to pass.
          The formation of pus activates the lymphocytes, which
          have been delivered from the bone marrow, the lymph
          nodes, and above all, the thymus. In a second wave of
          defence, the newly arriving defence cells attack every-
          thing they find around, including cell debris, available an-
          tigens, and even old white blood cells. These defence
          cells are the real eater cells — the macrophages, a type
          of phagocyte.


            The First Aid Forces: The Macrophages
            When the war becomes intense, the macrophages
          swing into action. Macrophages operate in a specific
          manner exclusive to themselves. They do not become
          involved in a one-to-one combat like the antibodies.
          Unlike the antibodies, they do not work with a system
          similar to a bomb aimed at a single target. Just like a gun
          firing lead shot, or a bomb that can be aimed at many
          targets together, the macrophages can destroy a great
          number of enemies together, all at the same time.
            Like all other defence cells, the macrophages are al-
          so derived from the bone marrow. The macrophages,
          which have a very long life span, can live for months, and
          even years. Despite their small size (10-15 microme-
          ters), they are highly crucial for human life. They pos-
          sess the ability to absorb and digest big molecules in the
          cell through phagocytosis (ingestion).
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