The document provides an introduction to the immune system, including: 1) The immune system defends the body against microorganisms and pathogens through non-specific and specific responses. 2) It is composed of molecules, cells, tissues and organs that provide both innate and adaptive protection. 3) The principal function of the immune system is to protect humans from pathogenic microorganisms like bacteria, viruses, fungi and parasites.

1. INTRODUCTION TO IMMUNE SYSTEMINTRODUCTION TO IMMUNE SYSTEM
PRESENTER
Shakira
Ghazanfar
PhDScholar
Shakira_sulehri@yahoo.com
‫الرحيم‬ ‫الرحمن‬ ‫اللة‬ ‫بسم‬‫الرحيم‬ ‫الرحمن‬ ‫اللة‬ ‫بسم‬

2. INTRODUCTION
Immunity : Defence capacity of the body to
combat diseases  counter infection.
Immune System: Molecules, cells, tissues and
organs which provide non-specific and specific
protection against, Microorganisms, Microbial
toxins, Tumor cells.

3. INTRODUCTION
Their collective and coordinative response to
introduction of foreign substance represent the
immune response.
Specific definition :
Immunity is a reaction to foreign substances
including microbes, as well as macromolecules
(proteins, polysacharides). The reactions
include cellular and molecular types (events).

4. Immunology lingo
* Antigen
* Any molecule that binds to immunoglobulin or T
cell receptor
* Pathogen
* Microorganism that can cause disease
* Antibody (Ab)
* Secreted immunoglobulin
* Immunoglobulin (Ig)
* Antigen binding molecules of B cells

5. NATURALLY ACQUIRED
IMMUNITY
* Active
* Antigens enter body naturally with response of
* Innate and adaptive immune systems
* Provides long term protection
* Passive
* Antibodies pass from mother to
* Fetus across placenta
* Infant in breast milk
* Provides immediate short term protection

6. ARTIFICIALLY ACQUIRED
IMMUNITY
* Active
* Antigens enter body through vaccination with response of
* Innate and adaptive immune systems
* Provides long term protection
* Passive
* Antibodies from immune individuals injected into body
* Referred to as
* Immune serum globulins (ISG)
* Immune globulins (IG)
* Gamma globulins
* Provides immediate short term protection

7. PRINCIPAL FUNCTION OF THE
IMMUNE SYSTEM
* To protect humans from pathogenic microorganisms
* Pathogenic microorganisms (Pathogens)
* Microorganisms capable of causing infection and/or disease
* Infection
* Ability of pathogen to enter host, multiply and stimulate an
immune response
* Disease
* Clinical manifestations associated with infection

8. BACTERIA, VIRUSES, FUNGI,
PARASITES—OH MY!
* Streptococcus pyogenes (Group A Streptococcus)
* Klebsiella pneumoniae
* Mycobacterium tuberculosis
* Ebola virus
* Human Immunodeficiency Virus (HIV)
* Aspergillus fumigatus
* Candida albicans
* Cryptococcus neoformans
* Cryptosporidium parvum
* Stronglyoides stercoralis
* Ascaris lumbricoides
* Plasmodium falciparum

9. DEFENSE MECHANISMS OF THE
HUMAN HOST
* Innate Mechanisms (Innate immunity)
* First line of defense
* Non-specific
* Adaptive Mechanisms (Adaptive immunity)
* Second line of defense
* Highly specific with memory
* Cooperation between mechanisms

10. ORIGIN OF CELLS OF THE IMMUNE
SYSTEM
* Derived from common progenitor cell in bone marrow
* Pluripotent hematopoietic stem cell
* Progenitor Stem Cells
* Erythroid lineage
* Erythrocytes and Megakaryocytes
* Myeloid lineage
* Monocyte/macrophage, dendritic cells, PMN’s, mast cells
* Lymphoid lineage
* Small and large lymphocytes

12. CELLS OF INNATE AND ADAPTIVE
IMMUNITY
* Myeloid Lineage
* Neutrophil
* Principal phagocytic cell of innate immunity
* Eosinophil
* Principal defender against parasites
* Basophil
* Functions similar to eosinophils and mast cells
* Referred to as
* Polymorphonuclear leukocytes (PMN’s)
* Nuclei are multilobed (2 to 5)
* Granulocytes
* Cytoplasmic granules

13. CELLS OF INNATE AND ADAPTIVE
IMMUNITY
* Myeloid lineage
* Monocytes
* Leukocytes with bean shaped or brain-like convoluted nuclei
* Circulate in blood with half life of 8 hours
* Precursors of tissue macrophages
* Macrophages
* Mononuclear phagocytic cells in tissue
* Derive from blood monocytes
* Participate in innate and adaptive immunity