BIOL 421 Immunology
Review Sheet
Ch. 1
Give a brief overview of the historical progression of the field of immunology as
described in class. Be able to briefly describe (in about 1-2 sentences) the
contributions of the following scientists:
Edward Jenner(developed the vaccine against smallpox in 1798),
Louis Pasteur(developed the vaccine against anthrax in 1881 and against rabies in
1885),
Elie Metchnikoff(he disovered phagocytes in 1883),
Emil von Behring & Shibasaburo Kitasato(they discovered that serum from animals
that’s immunized with diphtheria would be able to transfer immunity to
unimmunized animals, that is known as passive immunity in 1890),
Elvin Kabat(he identified the components of the serum that are antibodies that are
responsible for immune activities in the serum in 1930s),
Merrill Chase(through transferring white blood cells between guinea pigs he was
able to discover immunity against tuberculosis in 1940s),
Bruce Glick(he explained that T cells mature in the thymus and that B cells develop
and mature in the bone marrow in 1956),
Jules Bordet(proved that nonpathogenic substances can be antigens in 1900),
Karl Landsteiner(he showed that animals are able to produce antibodies against
almost any nonself-organic chemical),
Paul Ehrlich(suggested the Selective theory in 1900 and that indicates that
certain blood cells have a variety of receptors. Once an antigen binds to one of
those receptors, the blood cell will produce more of that specific type of
receptor, considering that an antigen selects the receptors),
Macfarlane Burnet&Niels Jerne&David Talmadge(they suggested the clonal
selection theory that says that A single B lymphocyte or T lymphocyte (out of
many B and T lymphocytes) specifically recognizes one specific antigen
through its membrane receptors, in which before the recognition of antigen,
the cell has its receptors specific to a certain antigen. This is known as
specificity. So, once the antigen binds to the receptor, the cell is activated and
therefore proliferates into a clone of daughter cells, all having the same
receptor specificity)
, Susumu Tonegawa(he discovered the genetic mechanism for the generation of
antibody diversity in 1976). &
Peter Medawar(in 1960 he received a noble price for his discovery of acquired
immunological tolerance)
Compare and contrast the Selective Theory versus the Instructional Theory.
The Selective Theory indicates that certain blood cells have a variety of
receptors. Once an antigen binds to one of those receptors, the blood cell will
produce more of that specific type of receptor, considering that an antigen
selects the receptors. This theory is almost proven correct, except for the part
that says that a variety of receptors are produced by the same cell, where
actually each cell has a specific receptor.
,The Instructional Theory states that the antigen that binds to the receptor on
a blood cell would teach the antibody how to fold into the correct
conformation around the antigen.
Describe the Clonal Selection Theory.
A single B lymphocyte or T lymphocyte (out of many B and T lymphocytes)
specifically recognizes one specific antigen through its membrane receptors,
in which before the recognition of antigen, the cell has its receptors specific to
a certain antigen. This is known as specificity. So, once the antigen binds to the
receptor, the cell is activated and therefore proliferates into a clone of
daughter cells, all having the same receptor specificity.
What are the four major classes of human pathogens?
Virus, bacterium, fungus, and parasite.
How is the immune response tailored?
The immune response is tailored, as the cells and molecules of the immune
system are activated under several conditions, depending on the chemical
structures that are present on the pathogen, whether the pathogen is
intracellular or extracellular, and depending on the location of the response.
Compare and contrast the innate and adaptive immune systems.
Innate:
1) Responds quickly.
2)It has limited specificity
3)It responds the same way to infections whether it is primary response or a
repeated one.
4)It is composed of barriers like the skin and tears, pattern recognition
receptors & phagocytes.
Adaptive:
1)Slowly responds
2)it becomes highly specific after infection
3) It responds more quickly and effectively upon a repeated response
4) It is composed of B & T cells, antibodies, and antigen specific receptors.
Briefly describe immunologic memory.
Immunologic memory is characterized by specifically and quickly recognizing
an antigen that has previously invaded the body. So, it is a characteristic of
adaptive immune system, in which during a secondary or repeated response
to the same antigen, memory cells get activated allowing the response to be
quicker and more effective than the primary response.
,BIOL 421 Immunology
Review Sheet
Ch. 2
Describe hematopoietic stem cells (HSCs).
HSCs are cells that are able to develop into all functionally specialized mature blood
cells in the body. There is less than 1 HSC in 50,000 cells in the bone marrow. HSCs
are able to regenerate themselves. They are quiescent as they aren’t mitotically
active. But few could divide into daughter cells, some of which continue to have the
same characteristics as stem cells, and others that differentiate into progenitor cells.
What are two primary characteristics of stem cells?
Stems cells are able to regenerate themselves and they are able to develop into
specialized cell types that are specific for a certain tissue.
Describe how HSCs are isolated
In vitro and in vivo colony formation assays could be performed. And, through a
process called panning, addition of bone marrow suspension to plastic plates coated
with lineage specific antibodies takes place. After culturing for about 1-2 hours, the
lineage negative or immature cells that didn’t bind to the antibodies are kept to find
out whether they express the markers specific for HSCs, through a technique known
as flow cytometry. The cells isolated should have the ability to proliferate and
differentiate into all blood cell types.
Which cell types are in the myeloid lineage?
Granulocytes (eosinophils, basophils, neutrophils)
Erythrocytes
Megakaryocytes
Myeloid antigen presenting cells (macrophages, monocytes, dendritic cells)
Which cell types are in the lymphoid lineage?
B lymphocytes(plasma cells), T lymphocytes (TH (helper) cells, TC (cytotoxic) cells),
natural killer cells, and NKT cells. Among those there are the naïve cells, effector
cells, and memory cells.
Briefly describe the various cell types
neutrophils : make up 50 to 70% of circulating leukocytes and they travel in the
blood for 7 to 10 hours before migrating to the tissues where they live only for few
days. They are the first line of immune defense to infection, where they sense a site
of infection by chemokines, and they phagocytose bacteria so efficiently.
, eosinophils :make up 1 to 3% of circulating leukocytes, phagocytic, motile, protect
against parasitic worms, as the eosinophilic granules release proteins that attack the
membrane of the worm, and secrete cytokines that regulate B & T lymphocytes.
Also, they could cause allergic symptoms.
, basophils : are relatively rare, nonphagocytic, release histamine from the granules
and thus causing allergic symptoms. Also, basophils protect against parasites.
, mast cells : mature after leaving the blood and they are found in a many tissues.
Also, they release histamine from the granules and cause allergic symptoms.
, megakaryocytes: live in the bone marrow, give rise to platelets,
, , erythrocytes : are responsible for delivering oxygen to the tissues and have a high
concentration of hemoglobin. Also, the mature erythrocytes are anuclear and an
innate immune response can be triggered through damaged RBCs.
,
dendritic cells :are most effective activators of naïve T cells and can arise from
myeloid and lymphoid lineages. Also, they’re responsible for antigen capture and
presentation. There are three ways that are used by those cells in their immature
forms to capture foreign antigen as they are outside the lymph nodes, that are:
phagocytosis, receptor-mediated endocytosis, and pinocytosis. Once dendritic cells
capture an antigen, they migrate to lymph nodes and become in antigen
presentation mode. So, the dendritic cells will no longer be involved in phagocytosis
and pinocytosis and naïve T cells become activated.
monocytes : make up 5 to 10% of leukocytes, travel to tissues, and differentiate into
macrophages and dendritic cells.
Macrophages : some participate in regeneration and repair of tissues while others
in an innate immune response. They’re professional phagocytes and antigen
presenting cells that have the ability to activate T cells. Some also have receptors for
antibodies such that they are able to more effectively phagocytose antigens coated
with the antibody.
natural killer cells: involved in innate immune system, have cytotoxic granules and
NK1.1 surface marker. Also, they make up 5 to 10% of the lymphocytes in peripheral
blood. They are professional cell killers as they have receptors for MHC 1 and
receptors for antibodies which allows them to recognize antigens the bound
antibodies recognize. When they recognize a pathogen, they release granules and
kill it.
TH cells : display CD4 and recognize antigen with MHC 2
TC cells: display CD8 and recognize antigen with MHC 1, and they mainly fight
intracellular pathogens.
B cells : mature in the bone marrow and have a B cell receptor. Each B cell has a
single surface antibody of a unique specificity and upon an infection those cells
improve their binding ability through somatic hypermutation. Also, B cells
differentiate into plasma cells that secrete antibodies.
What is opsonization? It’s when antibody-coated-antigens are engulfed by a
phagocyte.
What are the primary lymphoid organs? Bone marrow and thymus Briefly
describe their functions. The bone marrow is the primary site for HSCs. It’s the
site of development of T cells and development & maturation of B cells. The
thymus is the site of maturation of T cells into functional T cells.
Which cells in the bone marrow coordinate HSC development?
Endothelial cells, reticular cells, osteoblasts, sympathetic neurons.
Describe the movement of HSCs through bone marrow as they mature? As they
mature, they migrate toward vascular niche.
Review Sheet
Ch. 1
Give a brief overview of the historical progression of the field of immunology as
described in class. Be able to briefly describe (in about 1-2 sentences) the
contributions of the following scientists:
Edward Jenner(developed the vaccine against smallpox in 1798),
Louis Pasteur(developed the vaccine against anthrax in 1881 and against rabies in
1885),
Elie Metchnikoff(he disovered phagocytes in 1883),
Emil von Behring & Shibasaburo Kitasato(they discovered that serum from animals
that’s immunized with diphtheria would be able to transfer immunity to
unimmunized animals, that is known as passive immunity in 1890),
Elvin Kabat(he identified the components of the serum that are antibodies that are
responsible for immune activities in the serum in 1930s),
Merrill Chase(through transferring white blood cells between guinea pigs he was
able to discover immunity against tuberculosis in 1940s),
Bruce Glick(he explained that T cells mature in the thymus and that B cells develop
and mature in the bone marrow in 1956),
Jules Bordet(proved that nonpathogenic substances can be antigens in 1900),
Karl Landsteiner(he showed that animals are able to produce antibodies against
almost any nonself-organic chemical),
Paul Ehrlich(suggested the Selective theory in 1900 and that indicates that
certain blood cells have a variety of receptors. Once an antigen binds to one of
those receptors, the blood cell will produce more of that specific type of
receptor, considering that an antigen selects the receptors),
Macfarlane Burnet&Niels Jerne&David Talmadge(they suggested the clonal
selection theory that says that A single B lymphocyte or T lymphocyte (out of
many B and T lymphocytes) specifically recognizes one specific antigen
through its membrane receptors, in which before the recognition of antigen,
the cell has its receptors specific to a certain antigen. This is known as
specificity. So, once the antigen binds to the receptor, the cell is activated and
therefore proliferates into a clone of daughter cells, all having the same
receptor specificity)
, Susumu Tonegawa(he discovered the genetic mechanism for the generation of
antibody diversity in 1976). &
Peter Medawar(in 1960 he received a noble price for his discovery of acquired
immunological tolerance)
Compare and contrast the Selective Theory versus the Instructional Theory.
The Selective Theory indicates that certain blood cells have a variety of
receptors. Once an antigen binds to one of those receptors, the blood cell will
produce more of that specific type of receptor, considering that an antigen
selects the receptors. This theory is almost proven correct, except for the part
that says that a variety of receptors are produced by the same cell, where
actually each cell has a specific receptor.
,The Instructional Theory states that the antigen that binds to the receptor on
a blood cell would teach the antibody how to fold into the correct
conformation around the antigen.
Describe the Clonal Selection Theory.
A single B lymphocyte or T lymphocyte (out of many B and T lymphocytes)
specifically recognizes one specific antigen through its membrane receptors,
in which before the recognition of antigen, the cell has its receptors specific to
a certain antigen. This is known as specificity. So, once the antigen binds to the
receptor, the cell is activated and therefore proliferates into a clone of
daughter cells, all having the same receptor specificity.
What are the four major classes of human pathogens?
Virus, bacterium, fungus, and parasite.
How is the immune response tailored?
The immune response is tailored, as the cells and molecules of the immune
system are activated under several conditions, depending on the chemical
structures that are present on the pathogen, whether the pathogen is
intracellular or extracellular, and depending on the location of the response.
Compare and contrast the innate and adaptive immune systems.
Innate:
1) Responds quickly.
2)It has limited specificity
3)It responds the same way to infections whether it is primary response or a
repeated one.
4)It is composed of barriers like the skin and tears, pattern recognition
receptors & phagocytes.
Adaptive:
1)Slowly responds
2)it becomes highly specific after infection
3) It responds more quickly and effectively upon a repeated response
4) It is composed of B & T cells, antibodies, and antigen specific receptors.
Briefly describe immunologic memory.
Immunologic memory is characterized by specifically and quickly recognizing
an antigen that has previously invaded the body. So, it is a characteristic of
adaptive immune system, in which during a secondary or repeated response
to the same antigen, memory cells get activated allowing the response to be
quicker and more effective than the primary response.
,BIOL 421 Immunology
Review Sheet
Ch. 2
Describe hematopoietic stem cells (HSCs).
HSCs are cells that are able to develop into all functionally specialized mature blood
cells in the body. There is less than 1 HSC in 50,000 cells in the bone marrow. HSCs
are able to regenerate themselves. They are quiescent as they aren’t mitotically
active. But few could divide into daughter cells, some of which continue to have the
same characteristics as stem cells, and others that differentiate into progenitor cells.
What are two primary characteristics of stem cells?
Stems cells are able to regenerate themselves and they are able to develop into
specialized cell types that are specific for a certain tissue.
Describe how HSCs are isolated
In vitro and in vivo colony formation assays could be performed. And, through a
process called panning, addition of bone marrow suspension to plastic plates coated
with lineage specific antibodies takes place. After culturing for about 1-2 hours, the
lineage negative or immature cells that didn’t bind to the antibodies are kept to find
out whether they express the markers specific for HSCs, through a technique known
as flow cytometry. The cells isolated should have the ability to proliferate and
differentiate into all blood cell types.
Which cell types are in the myeloid lineage?
Granulocytes (eosinophils, basophils, neutrophils)
Erythrocytes
Megakaryocytes
Myeloid antigen presenting cells (macrophages, monocytes, dendritic cells)
Which cell types are in the lymphoid lineage?
B lymphocytes(plasma cells), T lymphocytes (TH (helper) cells, TC (cytotoxic) cells),
natural killer cells, and NKT cells. Among those there are the naïve cells, effector
cells, and memory cells.
Briefly describe the various cell types
neutrophils : make up 50 to 70% of circulating leukocytes and they travel in the
blood for 7 to 10 hours before migrating to the tissues where they live only for few
days. They are the first line of immune defense to infection, where they sense a site
of infection by chemokines, and they phagocytose bacteria so efficiently.
, eosinophils :make up 1 to 3% of circulating leukocytes, phagocytic, motile, protect
against parasitic worms, as the eosinophilic granules release proteins that attack the
membrane of the worm, and secrete cytokines that regulate B & T lymphocytes.
Also, they could cause allergic symptoms.
, basophils : are relatively rare, nonphagocytic, release histamine from the granules
and thus causing allergic symptoms. Also, basophils protect against parasites.
, mast cells : mature after leaving the blood and they are found in a many tissues.
Also, they release histamine from the granules and cause allergic symptoms.
, megakaryocytes: live in the bone marrow, give rise to platelets,
, , erythrocytes : are responsible for delivering oxygen to the tissues and have a high
concentration of hemoglobin. Also, the mature erythrocytes are anuclear and an
innate immune response can be triggered through damaged RBCs.
,
dendritic cells :are most effective activators of naïve T cells and can arise from
myeloid and lymphoid lineages. Also, they’re responsible for antigen capture and
presentation. There are three ways that are used by those cells in their immature
forms to capture foreign antigen as they are outside the lymph nodes, that are:
phagocytosis, receptor-mediated endocytosis, and pinocytosis. Once dendritic cells
capture an antigen, they migrate to lymph nodes and become in antigen
presentation mode. So, the dendritic cells will no longer be involved in phagocytosis
and pinocytosis and naïve T cells become activated.
monocytes : make up 5 to 10% of leukocytes, travel to tissues, and differentiate into
macrophages and dendritic cells.
Macrophages : some participate in regeneration and repair of tissues while others
in an innate immune response. They’re professional phagocytes and antigen
presenting cells that have the ability to activate T cells. Some also have receptors for
antibodies such that they are able to more effectively phagocytose antigens coated
with the antibody.
natural killer cells: involved in innate immune system, have cytotoxic granules and
NK1.1 surface marker. Also, they make up 5 to 10% of the lymphocytes in peripheral
blood. They are professional cell killers as they have receptors for MHC 1 and
receptors for antibodies which allows them to recognize antigens the bound
antibodies recognize. When they recognize a pathogen, they release granules and
kill it.
TH cells : display CD4 and recognize antigen with MHC 2
TC cells: display CD8 and recognize antigen with MHC 1, and they mainly fight
intracellular pathogens.
B cells : mature in the bone marrow and have a B cell receptor. Each B cell has a
single surface antibody of a unique specificity and upon an infection those cells
improve their binding ability through somatic hypermutation. Also, B cells
differentiate into plasma cells that secrete antibodies.
What is opsonization? It’s when antibody-coated-antigens are engulfed by a
phagocyte.
What are the primary lymphoid organs? Bone marrow and thymus Briefly
describe their functions. The bone marrow is the primary site for HSCs. It’s the
site of development of T cells and development & maturation of B cells. The
thymus is the site of maturation of T cells into functional T cells.
Which cells in the bone marrow coordinate HSC development?
Endothelial cells, reticular cells, osteoblasts, sympathetic neurons.
Describe the movement of HSCs through bone marrow as they mature? As they
mature, they migrate toward vascular niche.
