Transcript cells

Innate vs adaptive immunity
Mike Kemeny
Professor of Immunology,
GKT School of Medicine and Dentistry,
King’s College, London, UK
Textbooks
Janeway & Travers
Immunobiology
Abbas Lichtman Pober
Cellular & Molecular Immunology
Peakman & Vergani
Basic and Clinical Immunology
Various Roitt textbooks
Useful web sites and reading
1. Immunologic Diseases
http://www.mic.ki.se/Diseases/c20.html excellent resource
A comprehensive list of links to websites related to immune diseases.
2. The PathoPlus Page
http://pathoplus.com/newpage7.htm
Good introductory lectures on cells of the immune system and inflammation.
3. The Macrophage Home Page
http://www.path.ox.ac.uk/sg
A recently updated introduction to the cells of the mononuclear phagocyte family.
4. Antigen Presentation
http://www.ultranet.com/~jkimball/BiologyPages/A/AntigenPresentation.html
A nice introduction to antigen presentation, part of Kimball's Biology Pages.
5. Clinical and basic Immunology tutorials
http://www.ozemail.com.au/~davidful/Net_Path_Immunology/tutes.html
What is the immune system for
1.
Protect against pathogens
2.
Eliminate damaged or malignant
cells
Virus
Role of the immune system is
Parasites
to protect from:
Tapeworms
Influenza
Polio mellitus
Malaria
Helminths
Fungi
Bacteria
Candida albicans
Tubercule bacillus
Staphylococci
Innate immunity

Immediate protection

Low specificity broad reactivity

Important for first exposure
The innate immune system

Physicochemical barriers: Skin, mucus, cilia
 Secreted agents:
Lysozyme, acidic pH, saliva,
urine

Protective organisms:
Commensal bacteria

Phagocytic cells:
Macrophages, Neutrophils
secrete free radicals
(superoxide and cationic
proteins)
 Natural Killer (NK) cells
Cell wall proteins
Bacterial DNA
DANGER!
Bacteria
Activated
dendritic cell
(DC)
Features of pattern recognition:
• Conserved receptors and ligands
• Invokes same response in immune system
• You are born with it (innate)
Comparison of Innate and Adaptive
immune system
Innate
Adaptive
Receptors/
ligands
Conserved
Diverse
Grade of
response
Invariant
Modulated
(ie memory)
Age
Fully mature at birth
Immature at birth
The innate immune system
 Ligands that bind pathogens:
Pattern recognition
receptors (Toll like
receptors, mannose
receptors)

Secreted agents:
 Complement activation:
Interferon (IFN) a, b, g
Alternative pathway secretion of
anaphylatoxins C3a and
C5a
The adaptive immune system

Later protection

High specificity

Important for lasting protection
Components of the adaptive immune
system

Molecules: Antibody
Complement
Cytokines

Cells:
Lymphocytes (T & B cells)
Natural Killer cells
Monocytes/Macrophages
Dendritic cells
Neutrophils & Eosinophils
Basophils/Mast cells
Cells of the immune system
• B cells
• T cells
• NK cells
• Monocytes/macrophages
• Neutrophils
• Eosinophils
• Basophils/Mast cells
Origin of cells involved in the
immune response
Myeloid progenitor
Haemopoietic stem cell
Monocyte
Lymphocyte
progenitor
Macrophage
Basophil
Dendritic cell
Neutrophil
B cell
NK cell
Thymus
Mast cell
CD8
T cell
CD4
T cell
Plasma
cell
Eosinophil
What is the immune system
A collection of cells and molecules that protect the
body against infection, malignancy and damaged
cells
Antigen
1.
A molecule that can be recognised by
the immune system
2.
Usually foreign to the body although our
own molecules can serve as antigens
3.
Proteins eg: Grass pollen, egg
albumin. bacterial endotoxin,
4.
Haptens eg:
proteins
Nickel salts which bind to
Antibody
1.
Specialised molecules that recognise
and bind to antigens
2.
All antibodies are immunoglobulins
B Lymphocytes
Qui ck Ti me™and a
GIF dec om pres sor
are needed to s ee th i s pi c tu re.
BBcell
cell

10% of blood mononuclear cells

Make immunoglobulin (antibody)

Each B cell only makes antibody of
one specificity

B cells that make antibody are called
plasma cells
Plasma
cell
Immunoglobulin
Epitope
Combining site
Antigen
Light chain
Hinge
Heavy chain