BASIC IMMUNOLOGY Flashcards
cells, tissues, and molecules
that mediate resistance to infections
Immune system
study of structure and function of
the immune system, study of the reactions of a
host when foreign substances are introduced into
the body.
Immunology
resistance of a host to pathogens and
their toxic effects
Immunity
collective and coordinated
response to the introduction of foreign
substances in an individual mediated by the cells
and molecules of the immune system
Immune response:
Role of Immune System
Defense against microbes
Defense against the growth of tumor cells
- kills the growth of tumor cells
Homeostasis
- destruction of abnormal or dead cells
Immune System: Organs
Tonsils and adenoids
Thymus
Lymph nodes
Spleen
Payer’s patches
Appendix
Lymphatic vessels
Bone marrow
Immune System: Cells
Lymphocytes
☐ T-lymphocytes
☐ B-Lymphocytes, plasma cells
☐ natural killer lymphocytes
Monocytes, Macrophage
Granulocytes
☐ neutrophils
☐ eosinophils
☐ basophils
are proteins
produced by plasma cells that binds selectively to a specific
antigens (microorganisms) enabling our immune system to fight
them efficiently.
Antibodies (also known as immunoglobulins)
are proteins in our plasma that inhibits or kills
foreign cells
Complements
are secreted proteins and act as signaling molecules
Cytokines
2 VARIATIONS OF CYTOKINES
INTERLEUKINS & INTERFERONS
signaling molecules expressed by white blood cells
(mostly helper T cells) and are involved in production of more
immune cell (differentiation)
INTERLEUKINS
are a group of signaling proteins made and released
by host cells in response to the presence of several viruses
INTERFERON
Two types of Immunity
INNATE(NON-ADAPTIVE)
ACQUIRED (ADAPTIVE)
☐ first line of immune response
☐ relies on mechanisms that exist before
infection
Innate (non-adaptive)
Second line of response (if innate fails)
☐ relies on mechanisms that adapt after infection
Acquired (adaptive)
Acquired (adaptive) is handled by what cells?
T- and B- lymphocytes
one cell determines one antigenic determinant
Acquired (adaptive)
Based on genetic make-up; in born
Relies on already formed components
Innate Immunity
what is the rate of response of innate immunity
Rapid response: within minutes of infection
Non-specific
same molecules / cells respond to a range of
pathogens
Innate Immunity
immunity with no memory
Innate Immunity
Innate Immunity does not lead to?
Clonal expansion
Components of Innate immunity
Mechanical barriers / surface
secretion
Humoral mechanisms
Cellular defense mechanisms
Mechanical barriers / surface
secretion:
skin, acidic pH in
stomach, cilia
Humoral mechanisms:
lysozymes, basic proteins,
complement, interferons
Cellular defense mechanisms
natural killer cells,
neutrophils, macrophages,
mast cells, basophils,
eosinophils
dilates blood vessel and induces inflammation through release of histamine and heparin. Recruits macrophages and neutrophils. Involved in wound healing and defense against pathogens but can also be responsible for allergic reactions
Mast Cell
Mast Cell location
Connective tissue; Mucous membrane
phagocytic cell that consumes foreign pathogens and cancer cells. stimulates response of other immune cells.
Macrophage
Macrophage location?
Migrate from blood vessels to the tissues
Kills tumor cells and virus infected cells.
Natural killer cell
Natural killer cell location?
Circulates in blood and migrates into tissues
Presents antigens on its surface, thereby triggering adaptive immunity
Dendritic cell
Dendritic cell location?
Present in epithelial tissue, including skin, lung, and tissues of the digestive tract. Migrates to lymph nodes upon activation
Differentiates into macrophages and dendritic cells in response to inflammation
Monocyte
Monocyte location?
Stored in spleen, moves through blood vessels to infected tissues
First responders at the site of infection or trauma, the abundant phagocytic cell represents 50-60 percent all leukocytes.
Neutrophil
Neutrophil location?
Migrates from the blood vessel into tissues.
Responsible for defense against parasites. releases histamines that cause inflammation and may be responsible for allergic reactions.
Basophil
Basophil location?
Circulates in blood and migrates into tissues.
Releases toxins that kill bacteria and parasites but also causes tissue damage.
Eosinophil
Eosinophil location?
Circulates in blood and migrates in tissues.
Second line of defense
Adaptive Immunity
Based upon resistance acquired throughout life
§ Relies on genetic events and cellular growth
Adaptive Immunity
rate of response of Adaptive Immunity
Responds more slowly, over few days
Is specific
§ Each cell responds to a single epitope on an
antigen
Adaptive Immunity
Adaptive Immunity lead to
clonal expansion
Natural active immunity:
Clinical, Sub-clinical
Infection
Artificial Active immunity
Vaccination:
Live, killed, purified
antigen vaccine
Natural passive immunity:
Via Breast milk,
Placenta; Vertically
transmitted
Artificial passive immunity:
Immune serum,
Immune cells
(Immunoglobulins)
Adaptive Immune Mechanisms
Cell-mediated immune response (CMIR)
Humoral immune response (HIR)
cell of Cell-mediated immune response (CMIR)
T-lymphocytes
Cell-mediated immune response (CMIR) eliminate _____microbes that survive
within phagocytes or other infected cells
intracellular
cells of Humoral immune response (HIR)
B-lymphocytes
Humoral immune response (HIR) is mediated by?
antibodies
Humoral immune response (HIR) eliminates
extra-cellular
microbes and their toxins
B lymphocytes recognize
specific antigens
☐ proliferate and
differentiate into
antibody-secreting
plasma cells
Humoral Response
Antibodies bind to specific
antigens on microbes;
destroy microbes via specific
mechanisms
Humoral Response
Some B lymphocytes evolve
into the resting state
memory cell
T-cell
☐ recognizes peptide antigen
on macrophage in
association with major histo
compatibility complex
(MHC) class
☐ identifies molecules on cell
surfaces
☐ helps body distinguish non
self materials
Cell Mediated Immune Response
T-cell goes into_____ cells
stage that is able to kill infected
cells
effectors
T- lympocytes 2 types
Helper T- lymphocytes (CD4+).
Cytolytic T-lymphocyte (CD8+)
activate phagocytes to kill
Helper T- lymphocytes (CD4+)
destroy infected cells
containing microbes or microbial proteins
Cytolytic T-lymphocyte (CD8+)
Primary response
☐ production of specific clones of ___ and ___
effector T
cells and memory clones
Primary response develops in
several days
Primary response does what in the infection?
Limits
more pronounced, faster
☐ more effective at limiting the infection
Secondary response
Secondary response examples
cytotoxic reactions against intracellular parasites, delayed
hypersensitivity (e.g., Tuberculin test) and allograft rejection
Antibodies (immunoglobulins)
§ Belong to the_____of serum proteins
gamma-globulin
fraction
shapes of antibodies
T and Y-shaped polypeptides
Antibodies is composed of:
2 identical heavy chains
§ 2 identical light chains
Five kinds of antibodies
IgG, IgM, IgA, IgD, IgE
Antibodies are
secreted into the
blood and mucosa,
where they bind to
and inactivate
foreign substances
such as pathogens
and toxins
Neutralization
Antibodies
facilitate
phagocytosis of
foreign
substances by
phagocytic cells
opsonization
Refers to the
clumping of
particles together,
is an antigen
antibody reaction
Agglutination
IgG: Monomer ; ______
IgM: ___________; ______
IgA: ______;______
IgD: ______;______
IgE:______;______
Gamma Heavy chain
Pentamer; Mu Heavy chain
Monomeric; Alpha Heavy Chain
Monomeric; Delta Heavy Chain
Monomeric; Epsilon Heavy Chain
