Page 76 - The Miracle of the Immune System

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THE MIRACLE OF THE IMMUNE SYSTEM

The T cell Pathway
In comparison to B cells, T cells must go through a much
more complicated course to be ready to commence their mis-
sion. Just like B cells, they, too, are simple cells in the be-
Lymphoid ginning. These simple cells go through a series of dif-
progenitor
ficult tests to become a T cell.
cell
In the first test, it is checked whether
the cell can recognize the enemy or not.
The cells recognizes the enemy with the
Lymphoblast assistance of "MHC"(Major Histo-
compatibility Complex) located on
Monoblast
the surface of the enemy,
Lymphocyte which is a molecule that
subjects the antigen to a se-
In lymph tissue
ries of chemical process-
B cell es and presents it to
Promonocyte
lymphocyte the T cells.
In blood
Eventually, only those
T- cell
cells that are able to identify the en-
lymphocyte
emy can survive. The others are not
tolerated and they are immediately de-
Monocyte
stroyed.
The recognition of enemy cells alone does
The white cells made in the
not ensure the survival of T cells. These cells
lymph system tissue develop
into lymphocytes (B cells and must also have a very good knowledge of the
T cells) or monocytes. harmless substances and the regular tissues of
Lymphocytes are key players
the human body so to as prevent unnecessary
in immune responses.
Mmonocytes can transform conflict, which will eventually harm the body.
into large phagocytic (engulf-
ing) cells called
macrophages.