Kuby Immunology 6/e

Chapter 1
Dr. Capers
Kindt • Goldsby • Osborne
Sixth Edition
Chapter 1
Overview of the Immune System
Copyright © 2007 by W. H. Freeman and Company
Discipline of immunology grew out of observation
that individuals who recovered from infectious
diseases were protected from disease
15th Century
Chinese and Turks tried to prevent smallpox
 Dried crust from pustules were inhaled or inserted into small
Lady Montagu had that technique done in her children
Edward Jenner
 Noticed that milkmaids that contracted cowpox were
immune to smallpox
 Innoculated small boy with fluid from cowpox pustule
 He then intentionally infected the boy with smallpox – the
child did not develop smallpox
Louis Pasteur
 Vaccinated sheep with heat-attenuated anthrax
 Then infected sheep with virulent strain of anthrax – they
did not develop anthrax
Last known naturally acquired case of smallpox
Is it still a threat?
In industrialized nations, measles, mumps,
whooping cough, tetanus, polio, and diptheria
are extremely rare or nonexistent
 This is due to vaccines!
 Prevent death, paralysis, deafness, blindness, mental
Metchnikoff demonstrated that certain white blood
cells were able to phagocytize microorganisms
Von Behring and Kitasato
 Demonstrated that serum (noncellular component of
blood) from animals immunized to diptheria could
transfer that immunity to non-immunized animals
Immune system evolved to protect multicellular
organisms from pathogens
Does this by 2 related activites
Recognition and response
Innate Immunity
 1st line of defense
 Molecular and cellular mechanisms deployed before an
 Distinguishes between self and pathogens but not
specialized to distinguish small differences in the
foreign particles
Adaptive Immunity
 Develops in response to infection
 Adapts to recognize, eliminate, and remember
Less specific
1st line of defense
 Barriers that protect host
 Skin
 Acidity of stomach
 Lysozymes in fluids
 Phagocytic cells
 Antimicrobial peptides (interferons, complement)
 Temperature
Highly specific
Characteristic attributes
 Antigenic specificity
 Antibodies can distinguish between 2 proteins that differ
in only 1 amino acid
 Diversity
 Immunologic memory
 Self-nonself recognition
Effective Immune response involves 2 groups
of cells
 Lymphocytes
 B cells
 T cells
 Antigen-presenting cells
B cells
Mature in bone marrow
Antigen binding receptor – Antibody
 Glycoproteins
2 identical polypeptides – heavy chains
2 shorter identical polypeptides – light chains
Antigen coated by antibody is eliminated in
several ways
 Antibody can cross-link several antigens, making it easier
to be ingested by phagocytic cells
 Activate complement system resulting in lysis of
T cells
Arise in bone marrow but mature in thymus
2 well define subpopulations of T cells
 T helper cells
 T cytotoxic cells
T cells
 Can only recognize
antigen bound to cell
membrane proteins
called Major
Complex (MHC)
 MHC molecules are
expressed by antigenpresenting cells
 B cells
 Macrophages
 Dendritic cells
T cells
 Cytokines secreted by TH cells can activate phagocytic
 TC cells can kill altered self-cells
 Cells infected by viruses
 Tumor cells
Antigen presenting cell associating with T cell
Initial encounter with antigen causes primary
Later contact with antigen will result in more
rapid response
Allergies and Asthma
Graft rejection
Autoimmune Disease