Diagram_of_Immune_systems_.pdf@123456778

This description outlines the basic elements and functions depicted in a diagram of the immune system, which helps in visualizing how different components work together to protect the body from infections.

1. DIAGRAMS OF THE
IMMUNE SYSTEM

3. Components of Human Immune
System

4. Branches of the Immune
System
BranchDefinitionDefense
against
Cells
involved
ExamplesCellularCell
Mediated
Viruses,
Fungi,
mycobacter
ia, other
intracellular
pathogens,
tumor cells
T
lymphocyte
s
Graft
rejection,
hypersensit
ivity
reaction,
elimination
of tumor
cells
HumoralAntibody
mediated
Bacteria
(extracellul
ar)
B
lymphocyte
s, plasma
cells
Antibody
production

5. Types of Immunity
TypeExplanationComponentsMemoryNatural or InnateNonspecific
defenses with
which one is born
Intact skin,
mucous
membranes,
stomach acidity,
cilia, mucus, skin
secretions,
lysozyme, IgA,
phagocytes,
complement,
Interferon,
Inflammation
No
Acquired or
Adaptive
Specific
responses to
eliminate a
microorganism
T cells, B cells,
plasma cells,
antibodies,
cytokines
Yes

6. Types of Acquired Immunity
I. Naturally Acquired Immunity:
Obtained in the course of daily life.
A. Naturally Acquired Active Immunity:
• Antigens or pathogens enter body naturally
•An individual infected with a microorganism produces an
antibody.
•Body generates an immune response to antigens.
•Immunity may be lifelong (chickenpox or mumps) or
temporary (influenza or intestinal infections).

7. B.Naturally Acquired Passive Immunity:
_An individual is protected by antibodies produced in
another individual.
•Antibodies pass from mother to fetus via placenta or
breast feeding (colostrum).
•No immune response to antigens.
•Immunity is usually short-lived (weeks to months).
•Protection until child’s immune system develops.

8. Types of Acquired Immunity (Continued)
II. Artificially Acquired Immunity: Obtained by
receiving a vaccine or immune serum.
1. Artificially Acquired Active Immunity:
•Antigens are introduced in vaccines
(immunization).
•Body generates an immune response to antigens.
•Immunity can be lifelong (oral polio vaccine) or
temporary (tetanus toxoid).
2. Artificially Acquired Passive Immunity:
• Preformed antibodies (antiserum) are
introduced into body by injection.
•Snake antivenom injection from horses or rabbits.
•Immunity is short lived (half life three weeks).
•Host immune system does not respond to
antigens.

11. Cells of the Immune System
CellFunctionCommentsEosinophilsSuppress inflammatory
reaction. Kill some
parasites.
Some phagocytic ability
BasophilsGranules contain
histamine and heparin.
Role in hypersensitivity
reactions
Some phagocytic ability.
Precursor of mast cell.
NeutrophilsPrincipal leukocyte
associated with
phagocytosis and
localized inflammatory
response. Granules
contain bactericidal
enzymes. Respond to
Chemotaxins
MonocytesPhagocytes. Respond to
Chemotaxins. Process
antigens and present to
lymphocytes.
Precursor of
macrophage.

12. Immunoglobulin Structure
Basic
structur
e
A four-chain polypeptide until that consists of two heavy chains
and two light chains held together by disulfide bonds.
Heavy
chains
The two heavy chains in the immunoglobulin molecule are always of
the same type. They determine the immunoglobulin class ( IgG, IgA,
IgM, IgD, IgE)
Light
Chains
K or L, Both kappa and lambda chains are found in all classes of
immunoglobulins, but only one type is present in a given molecule.
Fab
fragment
Fragment antigen-binding. Consists of one light chain and one-half of
a heavy chain. The intact immunoglobulin has two Fab fragments,
each representing one antigen-binding site.
Fc
fragment
Fragment crystalline. The carboxy-terminal halves of the two heavy
chains. This portion of the molecule has no antigen binding ability.

13. Constant regionThe carboxy-terminal end of the immunoglobulin
molecule, where the amino acid sequence is the same
for all chains of that type.
Variable regionThe amino-terminal end of the immunoglobulin molecule,
where the amino acid sequence varies. This part of the
molecule is responsible for the specificity of a particular
immunoglobulin. Also known as the antigen-recognition unit.
Hypervariable
region
Regions within the variable region that actually form the
antigen-binding site. Through changes in the hypervariable
region, an immense diversity of antigen-binding sites can
be created.
Hinge regionThe flexible portion of the heavy chain, located between
the first and second constant regions. This allows the
molecule to bend to let the two antigen-binding sites
operate independently.
Joining chainA glycoprotein that serves to link immunoglobulin
monomers together. Only found in IgM and secretory IgA
molecules.

14. Antibodies are Produced by B
Lymphocytes

15. Antibodies are Proteins that Recognize Specific
Antigens

16. https://www.youtube.com/watch?
v=OI_PqO2RW8g

17. Immunoglobulin Classes
I. IgG
uStructure: Monomer
uPercentage serum antibodies: 80%
uLocation: Blood, lymph, intestine
uHalf-life in serum: 23 days
uComplement Fixation: Yes
uPlacental Transfer: Yes
uKnown Functions: Enhances phagocytosis,
neutralizes toxins and viruses, protects fetus
and newborn.

18. Immunoglobulin Classes
II. IgM
uStructure: Pentamer
uPercentage serum antibodies: 5-10%
uLocation: Blood, lymph, B cell surface
(monomer)
uHalf-life in serum: 5 days
uComplement Fixation: Yes
uPlacental Transfer: No
uKnown Functions: First antibodies produced
during an infection. Effective against microbes
and agglutinating antigens.

19. Immunoglobulin Classes
III. IgA
uStructure: Dimer
uPercentage serum antibodies: 10-15%
uLocation: Secretions (tears, saliva, intestine,
milk), blood and lymph.
uHalf-life in serum: 6 days
uComplement Fixation: No
uPlacental Transfer: No
uKnown Functions: Localized protection of
mucosal surfaces. Provides immunity to
infant digestive tract.

20. Immunoglobulin Classes
IV. IgD
uStructure: Monomer
uPercentage serum antibodies: 0.2%
uLocation: B-cell surface, blood, and lymph
uHalf-life in serum: 3 days
uComplement Fixation: No
uPlacental Transfer: No
uKnown Functions: In serum function is
unknown. On B cell surface, initiate immune
response.

21. Immunoglobulin Classes
V. IgE
uStructure: Monomer
uPercentage serum antibodies: 0.002%
uLocation: Bound to mast cells and basophils
throughout body. Blood.
uHalf-life in serum: 2 days
uComplement Fixation: No
uPlacental Transfer: No
uKnown Functions: Allergic reactions.
Possibly lysis of worms.

22. Antigens
uMost are proteins or large polysaccharides
from a foreign organism.
•Microbes: Capsules, cell walls, toxins, viral
capsids, flagella, etc.
•Nonmicrobes: Pollen, egg white , red blood cell
surface molecules, serum proteins, and surface
molecules from transplanted tissue.
uLipids and nucleic acids are only antigenic
when combined with proteins or
polysaccharides.
uMolecular weight of 10,000 or higher.
•Hapten: Small foreign molecule that is not antigenic. Must
be coupled to a carrier molecule to be antigenic. Once
antibodies are formed they will recognize hapten.

23. Antigens
Epitope:
uSmall part of an antigen that
interacts with an antibody.
uAny given antigen may have several
epitopes.
uEach epitope is recognized by a
different antibody.

24. Epitopes: Antigen Regions that
Interact with Antibodies

27. Phagocytosis
•Process of engulfing foreign particle.
•Stages of Phagocytosis
•1. Initiation
•> initiated by cell injury e.g. by cell trauma,
microorganism multiplication.
•ACtivated phagocytes- exhibit cell receptors
( Enhance of Adherence of foreign Particle)

28. •Basic Antibody Structure
https://www.youtube.com/watch?v=NHtl8HnhsqE
•Fab, Fc structure of antibody
•https://www.youtube.com/watch?v=8CbjogONFog
•Ag-Ab reactions
•https://www.youtube.com/watch?v=N3L4kQqsGPQ
Phagocytosis
•https://www.youtube.com/watch?v=sJ8Sz0CcNKo
•Inflammation and Fever
•https://www.youtube.com/watch?v=hQyz_YGX5Fs
•Cytokines
•https://www.youtube.com/watch?v=9wdZLvNKyQY
•Interferons
•https://www.youtube.com/watch?v=92Kjr-w2ZRc

29. •MHC
•https://www.youtube.com/watch?v=t9TvTmddanE
•MHC1
•https://www.youtube.com/watch?v=qyt-yTy-EEM
•MHCII
•https://www.youtube.com/watch?v=-gHgp6EBWJc
•Complement System
•https://www.youtube.com/watch?v=d6qFPegEYV0

30. •Complement Nomenclature
•https://www.youtube.com/watch?v=zbf27pCTjRQ
•Alternative Pathway
•https://www.youtube.com/watch?v=1Cho6NPtsVw
•Lectin Pathway
•https://www.youtube.com/watch?v=utQdPPeeTLQ
•Classical Pathway
•https://www.youtube.com/watch?v=Y7Xo-5WiwGg
•MAC (common pathway)
•https://www.youtube.com/watch?v=XFFd0eGgRFU