BioPharma_02_Cells and Organs of the IS_Stu Ver
Content
Biotechnology and Pharmacology Course – Topic 02
CELLS AND ORGANS
OF THE IMMUNE SYSTEMS
A/Prof. Le Van Dong MD., PhD
Former Deputy Head, Department of Immunology
Vietnam Military Medical University
Tel: 0989058710; Email: [email protected]
EDUCATION
RESEARCH
INDUSTRY/ TREATMENT
Aims
Know origins and places of
maturation, differentiation process,
specific surface markers and
functions of each immune cells.
Understand
components
and
functions of the two types of
lymphoid organs.
Haematopoiesis
Haematopoiesis
Blood forming process
Take place in bone marrow
Strictly controlled process
To give rise to all blood and immune cells
All blood cell types originate from a single
hematopoietic stem cell (hSC)
hSC transplantation is common practice to cure
diseases related to blood forming disorders
2. IMMUNE CELLS
EDUCATION
RESEARCH
INDUSTRY/ TREATMENT
2.1. B lymphocyte
Origin: Bone marrow
Maturation: Bone marrow
B cell surface markers
Surface immunoglobulin (SIg) to
serve as B cell receptor (BCR) for
antigen.
Each
cell has thousands of SIg
molecules on the surface. All of them
have the same specificity, they can bind
to ONLY ONE structure called antigenic
determinant or epitope.
The specificity is defined by gene
arrangement.
CD19: to define it is B cell.
CD molecule
CD: Cluster of Differentiation.
CD is unique structure, usually at a cell’s surface,
to which specific antibodies bind.
By knowing the CDs we can distinguish among
cell types (“who is who”).
CD = Cell Determining molecule.
CD was first applied for human leukocyte antigen,
then extended to other cells.
B lymphocyte differentiation
Stem cell
Pro-B
Pre-B
Immature B
Mature B
Peripheral lymphoid organs (lymph nodes, spleen etc.)
Abbas A. K and Lichtman A. H
Basic Immunology 3rd Ed © Saunders 2011
B lymphocyte differentiation
During differentiation (maturation) process, genes are
rearranged to form molecules that contribute to the
functions of the cell.
B cell function:
produce antibody
2.2. T lymphocyte
Origin: Bone marrow
Maturation: Thymus
Kuby Immunology 5th Ed ©Freeman and Company 2003
T cell markers
CD2:
Involve
in cell signaling
Natural
receptor for sheep
red blood cell
E
rosette assay for
determination of T
lymphocyte
T cell Surface markers
CD3:
Specific
Part
for T lymphocyte
of T cell receptor (signaling)
T cell receptor for antigen (TCR):
Many molecules, same specificity
Some cells has, either:
CD4
molecule, helper T cell (TH)
(target of HIV)
CD8,
cytotoxic T cell (TC)
Abbas A. K and Lichtman A. H
Basic Immunology 3rd Ed © Saunders 2011
B cell and T cell receptors
Abbas A. K and Lichtman A. H
Basic Immunology 3rd Ed ©
Saunders 2011
Similar in structures
Unique specificity - both formed by gene arrangement
Abbas A. K and Lichtman A. H
Basic Immunology 3rd Ed © Saunders 2011
T cell differentiation
Bone marrow
Thymus
T cell differentiation
•During differentiation
(maturation) process,
genes are rearranged to
form molecules that
contribute to the
functions of the cell.
•Some molecules
appear, some disappear
during the maturation of
the cell
T cell functions
3 types with distinct functions:
TH
helps B lymphocyte to produce
antibody; macrophage to kill
bacteria.
TC
kills (by cytotoxicity)
virusinfected cell and cancer cell.
Note:
some TH cell regulate
immune response and called
regulate T cell (Treg)
TH helps B lymphocyte to produce antibodies
Without T helper, B cell
can not produce (or very
little) antibody.
With T helper, B cell can
produce more antibodies
(types and quantity of
antibodies).
TH helps macrophage to kill bacteria
Without T helper,
macrophage can eat the
bacteria but can not kill
them.
With T helper,
macrophage can kill the
bacteria which have been
eaten but survive inside
the cell).
OK,
macrophage
kill them!
Tc kills virus-infected cell and
cancer cell
Figure 1-25
TH and TC work together: TH calls more TC
come to kill microbe
Treg controls (regulates) the immune response
(stop the immune response, do not harm to body)
T cell’s markers and functions
CD2:
signaling
CD3:
signaling, part of TCR
T
cell receptor: to recognize antigen
Either:
CD4 (TH): helper T cell
CD8 (TC): cytotoxicity T cell
2.3. Natural killer
(NK) cell
NK cell kills virusinfected
cells
and
cancer cells. Person
who lack of NK cells
has higher risk of
cancer
and
viral
infection.
NK produces IFN-γ to
activate macrophage
to kills more bacteria.
Abbas A. K and Lichtman A. H
Basic Immunology 3rd Ed © Saunders 2011
NK cell kills virus-infected cell and cancer cell
Notes
B and T lymphocytes are “professional” cells
of the immune system. They not only react
wisely (specifically) to different microbes
which they encounter but also memorize
them, as such they can react faster and more
effectively when meeting them again.
Vaccination is the way to “train” by “exercise”
(practicing to fight against vaccine) for
memorizing the pathogen, that provide the
body protection when the real pathogen enter
the body.
NK cell has no immunological memory, they
just kill the body’s modified cells.
2.4. Phagocytes
Phagocyte “eats” microbe and provide signals
to initiate an immune response
2.5. Basophil and Mast cell
Mast cells
membrane.
are
under
skin
and
mucous
Basophils are in the blood.
Both have receptor for IgE antibody on the
surface of the cell.
Involve in allergic reaction.
Mast cell
Basophil
2.6. Eosinophil
2.7. Antigen presenting cell - APC
APCs include:
Macrophage
Dendritic
cell
B lymphocyte
All have ability to capture antigen, process them
into small peptide and presenting those
fragments to surface of the cell for T cell to
recognize them.
There are MHC class II molecule on the surface
as tool for antigen presentation.
APCs
3. LYMPHOID ORGANS
Two type of lymphoid organs:
–
Central/primary lymphoid organs
–
Peripheral/secondary lymphoid organs
EDUCATION
RESEARCH
INDUSTRY/ TREATMENT
Lymphoid organs/tisue
Central/primary
lymphoid organs:
Peripheral/secondary
lymphoid organs:
where the lymphocyte
growth without the
stimulation by antigen
Where lymphocyte
encounter antigen and
growth strongly after
stimulation by antigen.
3.1. Central lymphoid organs
Thymus and Bone marrow
Thymus “educates” pre-T lymphocyte
to mature T lymphocyte
Maturation process of lymphocytes
Maturation/differentiation process of
lymphocytes in central lymphoid organs
Bone marrow and thymus stromal cells “educate” prelymphocyte to mature lymphocyte.
The lymphocyte undergo selection processes:
Positive selection: keep the functioning ones
Negative selection: remove the “betrayer”
The lymphocyte learn to differentiate which is belong to
the body own (self) and which is not (non-self). The cell
does not allow to react with self ones.
Only GOOD cells are allowed to mature.
3.2. Peripheral lymphoid organs
3.2.1. Lymph node
To capture antigens which enter body through skin and
mucous membrane
3.2.2. Spleen
To capture antigens which enter
blood stream
3.2.3. Lymphoid tissue in the mouth
To capture antigens which enter mouth area
3.2.4. Lymphoid tissue in the gut
To capture antigens which enter through the gut
4. Circulation of lymphocytes
Abbas A. K and Lichtman A. H
Basic Immunology 3rd Ed © Saunders 2011
Circulation of lymphocytes
Block of lymphatic vein
caused by parasite
Wuchereria bancrofti
SUMMARY
Lymphocytes
B
(bone marrow), produce antibodies
T (thymus)
TCD4+: helper T cell (TH)
TCD8+: cytotoxicity T cell (TC)
Other cells: phagocytes, APCs, basophil and
mast cell, eosinophil
Lymphoid organs
Central:
Bone marrow, thymus
Peripheral: lymph nodes, spleen, GALT
Review Questions
1.
Origin, surface markers, differentiation
process and functions of B lymphocyte?
2.
Origin, surface markers, differentiation
process and functions of T lymphocyte?
3.
Functions of neutrophil, macrophage,
eosinophil, basophil, and mast cell.
4.
What are
properties.
5.
What are central/ primary and peripheral/
secondary lymphoid organs.
APCs
and
their
common
CELLS AND ORGANS
OF THE IMMUNE SYSTEMS
A/Prof. Le Van Dong MD., PhD
Former Deputy Head, Department of Immunology
Vietnam Military Medical University
Tel: 0989058710; Email: [email protected]
EDUCATION
RESEARCH
INDUSTRY/ TREATMENT
Aims
Know origins and places of
maturation, differentiation process,
specific surface markers and
functions of each immune cells.
Understand
components
and
functions of the two types of
lymphoid organs.
Haematopoiesis
Haematopoiesis
Blood forming process
Take place in bone marrow
Strictly controlled process
To give rise to all blood and immune cells
All blood cell types originate from a single
hematopoietic stem cell (hSC)
hSC transplantation is common practice to cure
diseases related to blood forming disorders
2. IMMUNE CELLS
EDUCATION
RESEARCH
INDUSTRY/ TREATMENT
2.1. B lymphocyte
Origin: Bone marrow
Maturation: Bone marrow
B cell surface markers
Surface immunoglobulin (SIg) to
serve as B cell receptor (BCR) for
antigen.
Each
cell has thousands of SIg
molecules on the surface. All of them
have the same specificity, they can bind
to ONLY ONE structure called antigenic
determinant or epitope.
The specificity is defined by gene
arrangement.
CD19: to define it is B cell.
CD molecule
CD: Cluster of Differentiation.
CD is unique structure, usually at a cell’s surface,
to which specific antibodies bind.
By knowing the CDs we can distinguish among
cell types (“who is who”).
CD = Cell Determining molecule.
CD was first applied for human leukocyte antigen,
then extended to other cells.
B lymphocyte differentiation
Stem cell
Pro-B
Pre-B
Immature B
Mature B
Peripheral lymphoid organs (lymph nodes, spleen etc.)
Abbas A. K and Lichtman A. H
Basic Immunology 3rd Ed © Saunders 2011
B lymphocyte differentiation
During differentiation (maturation) process, genes are
rearranged to form molecules that contribute to the
functions of the cell.
B cell function:
produce antibody
2.2. T lymphocyte
Origin: Bone marrow
Maturation: Thymus
Kuby Immunology 5th Ed ©Freeman and Company 2003
T cell markers
CD2:
Involve
in cell signaling
Natural
receptor for sheep
red blood cell
E
rosette assay for
determination of T
lymphocyte
T cell Surface markers
CD3:
Specific
Part
for T lymphocyte
of T cell receptor (signaling)
T cell receptor for antigen (TCR):
Many molecules, same specificity
Some cells has, either:
CD4
molecule, helper T cell (TH)
(target of HIV)
CD8,
cytotoxic T cell (TC)
Abbas A. K and Lichtman A. H
Basic Immunology 3rd Ed © Saunders 2011
B cell and T cell receptors
Abbas A. K and Lichtman A. H
Basic Immunology 3rd Ed ©
Saunders 2011
Similar in structures
Unique specificity - both formed by gene arrangement
Abbas A. K and Lichtman A. H
Basic Immunology 3rd Ed © Saunders 2011
T cell differentiation
Bone marrow
Thymus
T cell differentiation
•During differentiation
(maturation) process,
genes are rearranged to
form molecules that
contribute to the
functions of the cell.
•Some molecules
appear, some disappear
during the maturation of
the cell
T cell functions
3 types with distinct functions:
TH
helps B lymphocyte to produce
antibody; macrophage to kill
bacteria.
TC
kills (by cytotoxicity)
virusinfected cell and cancer cell.
Note:
some TH cell regulate
immune response and called
regulate T cell (Treg)
TH helps B lymphocyte to produce antibodies
Without T helper, B cell
can not produce (or very
little) antibody.
With T helper, B cell can
produce more antibodies
(types and quantity of
antibodies).
TH helps macrophage to kill bacteria
Without T helper,
macrophage can eat the
bacteria but can not kill
them.
With T helper,
macrophage can kill the
bacteria which have been
eaten but survive inside
the cell).
OK,
macrophage
kill them!
Tc kills virus-infected cell and
cancer cell
Figure 1-25
TH and TC work together: TH calls more TC
come to kill microbe
Treg controls (regulates) the immune response
(stop the immune response, do not harm to body)
T cell’s markers and functions
CD2:
signaling
CD3:
signaling, part of TCR
T
cell receptor: to recognize antigen
Either:
CD4 (TH): helper T cell
CD8 (TC): cytotoxicity T cell
2.3. Natural killer
(NK) cell
NK cell kills virusinfected
cells
and
cancer cells. Person
who lack of NK cells
has higher risk of
cancer
and
viral
infection.
NK produces IFN-γ to
activate macrophage
to kills more bacteria.
Abbas A. K and Lichtman A. H
Basic Immunology 3rd Ed © Saunders 2011
NK cell kills virus-infected cell and cancer cell
Notes
B and T lymphocytes are “professional” cells
of the immune system. They not only react
wisely (specifically) to different microbes
which they encounter but also memorize
them, as such they can react faster and more
effectively when meeting them again.
Vaccination is the way to “train” by “exercise”
(practicing to fight against vaccine) for
memorizing the pathogen, that provide the
body protection when the real pathogen enter
the body.
NK cell has no immunological memory, they
just kill the body’s modified cells.
2.4. Phagocytes
Phagocyte “eats” microbe and provide signals
to initiate an immune response
2.5. Basophil and Mast cell
Mast cells
membrane.
are
under
skin
and
mucous
Basophils are in the blood.
Both have receptor for IgE antibody on the
surface of the cell.
Involve in allergic reaction.
Mast cell
Basophil
2.6. Eosinophil
2.7. Antigen presenting cell - APC
APCs include:
Macrophage
Dendritic
cell
B lymphocyte
All have ability to capture antigen, process them
into small peptide and presenting those
fragments to surface of the cell for T cell to
recognize them.
There are MHC class II molecule on the surface
as tool for antigen presentation.
APCs
3. LYMPHOID ORGANS
Two type of lymphoid organs:
–
Central/primary lymphoid organs
–
Peripheral/secondary lymphoid organs
EDUCATION
RESEARCH
INDUSTRY/ TREATMENT
Lymphoid organs/tisue
Central/primary
lymphoid organs:
Peripheral/secondary
lymphoid organs:
where the lymphocyte
growth without the
stimulation by antigen
Where lymphocyte
encounter antigen and
growth strongly after
stimulation by antigen.
3.1. Central lymphoid organs
Thymus and Bone marrow
Thymus “educates” pre-T lymphocyte
to mature T lymphocyte
Maturation process of lymphocytes
Maturation/differentiation process of
lymphocytes in central lymphoid organs
Bone marrow and thymus stromal cells “educate” prelymphocyte to mature lymphocyte.
The lymphocyte undergo selection processes:
Positive selection: keep the functioning ones
Negative selection: remove the “betrayer”
The lymphocyte learn to differentiate which is belong to
the body own (self) and which is not (non-self). The cell
does not allow to react with self ones.
Only GOOD cells are allowed to mature.
3.2. Peripheral lymphoid organs
3.2.1. Lymph node
To capture antigens which enter body through skin and
mucous membrane
3.2.2. Spleen
To capture antigens which enter
blood stream
3.2.3. Lymphoid tissue in the mouth
To capture antigens which enter mouth area
3.2.4. Lymphoid tissue in the gut
To capture antigens which enter through the gut
4. Circulation of lymphocytes
Abbas A. K and Lichtman A. H
Basic Immunology 3rd Ed © Saunders 2011
Circulation of lymphocytes
Block of lymphatic vein
caused by parasite
Wuchereria bancrofti
SUMMARY
Lymphocytes
B
(bone marrow), produce antibodies
T (thymus)
TCD4+: helper T cell (TH)
TCD8+: cytotoxicity T cell (TC)
Other cells: phagocytes, APCs, basophil and
mast cell, eosinophil
Lymphoid organs
Central:
Bone marrow, thymus
Peripheral: lymph nodes, spleen, GALT
Review Questions
1.
Origin, surface markers, differentiation
process and functions of B lymphocyte?
2.
Origin, surface markers, differentiation
process and functions of T lymphocyte?
3.
Functions of neutrophil, macrophage,
eosinophil, basophil, and mast cell.
4.
What are
properties.
5.
What are central/ primary and peripheral/
secondary lymphoid organs.
APCs
and
their
common
