Human Immune system (HIS)

1. Human Immune system (HIS)

2. Immunology

• Immunology is
the study of the
strategies and
mechanisms that
the body uses to
rid itself of
foreign
substances

3. Organs of the immune system

The organs are:
- Spleen
- Lymph nodes
- Mucosal nodes
- Reticulo-endothelial
system
• - Thymus

4. Spleen

• The spleen is
involved in:
• degradation of old
and dead
erythrocytes.
• storage of blood as a
reserve
• production of
lymphocytes
• production of fetal
blood until birth

5. Lymph nodes

• Lymph nodes are
involved in both
blood production
and body defense
by capturing
microbes
• In the event of
major infection,
the lymph nodes
can become
enlarged

6. Reticulo-endothelial System

• The reticuloendothelial system is
made up of Kuppfer
cells of the liver and
reticular cells of red
bone marrow
• This system defends
the body against
hazardous
substances by
phagocytosis

7. Thymus

• Defends the body against infection by producing
lymphocytes

8. Immunity

• Immunity is the recognition and removal of
molecules foreign to the body

9.

• Antigen – foreign substance
• Antibody is produced against antigen, and destroys
antigen

10. Acquisition of Immunity

• Active immunity: the
individual alone produces
antibodies against an
antigen
• Passive immunity: the
individual is given prepared
antibodies

11. Vaccines

• Vaccines function as a
precaution before
exposure to the illness
• They are composed of a
physiological fluid and a
weakened or dead
microbe
• Properties:
• - they should have little
or no side effects
• - any vaccination should
not be given during
illness or after surgery
• - they have allergic
functions.

12. Types of Immunity

• Immunity is
maintained
by two
pathways:
• non-specific
immunity
• specific
immunity

13. Non-specific Immunity

• Barriers nonspecifically
prevent microbes from
entering the body
• It is maintained by
interferon (inactivate
viruses and degrades
cancer cells),
phagocytosis, skin,
tears and sweat,
gastric juices, hair and
mucus in the
respiratory tract

14.

15. Specific immunity

• It is based on
production of a
different type of
antibody against each
different type of
microorganism
antigen

16. AIDS

• AIDS is caused by a
virus called HIV
(Human
Immunodeficiency
Virus)
• This can damage the
body's immune
system so that it
cannot fight certain
infections