Immunology Basics - Immunological Computation: Theory and Applications - page 2

Lymphatic
vessel
Blood
capillary

Adenoid
Tonsil
Lymph nodes
Thoracic duct
entering vein
Thymus

Tissue cells
Interstitial
fluid

Right lymphatic
duct entering
vein

Lymphatic
capillary

(b)

Thoracic
duct
Peyer's
patch (small
intestine)

Spleen

Masses of
lymphocytes and
macrophages

Appendix

Lymphatic
vessels

Bone
marrow

(a) (c)

Figure 1.1 Functional Components of the immune system.

1.1 Functional Elements of the Immune System
h e immune system is a collection of organs, cells, and molecules responsible for deal-
ing with potentially harmful invaders; it also has other functionalities in the body.

1.1.1 Organs

h e organs, which constitute the immune system, can be classifi ed into central
lymphoid organs and peripheral lymphoid organs. h e purpose of central lymphoid
organs is to generate and assist mature immune cells (lymphocytes). Such organs
include the bone marrow and the thymus. However, peripheral lymphoid organs
facilitate the interaction between lymphocytes and antigens, as the antigen concen-
tration increases in these organs. Peripheral lymphoid organs include lymph nodes,
the spleen, and mucosal and submucosal tissues of the alimentary and respiratory
tracts. Figure 1.1 shows the components of the biological immune system.

1.1.1.1 Bone Marrow

In an abstract sense, naive immune cells are initially generated in the bone marrow
and are derived through a process called hematopoiesis. During hematopoiesis,