Adaptive Immunity Flashcards
____ allows the body to recognize, remember, and respond to a specific stimulus, an antigen.
Adaptive Immunity
Adaptive Immunity allows the body to ____ to a specific stimulus, an antigen.
- Recognize
- Remember
- Respond
____ can result in the elimination of microorganisms and recover from disease and the host often acquires immunologic memory.
Adaptive Immunity
Adaptive immunity can result in the elimination of microorganisms and recover from disease and the host often acquires ____.
immunologic memory
____ allows the host to respond more effectively if reinfection with the same microorganism occurs.
Adaptive Immunity
Components of the Adaptive Immune System
- Cellular
- Humoral
Cellular Adaptive Immune System Components
- T lymphocytes
- B lymphocytes
- Plasma cells
Humoral Adaptive Immune System Components
- Antibodies
- Cytokines
____ are the key cells involved in the adaptive immune response.
Lymphocytes
____ represent between 20-40% of the circulating WBCs.
Lymphocytes
Lymphocytes represent between ____ of the circulating WBCs.
20-40%
____ are 7-10 um in diameter, and are almost the same size as the RBCs.
Lymphocytes
Lymphocytes are ____ in diameter, and are almost the same size as the RBCs.
7-10 um
Lymphocytes are almost the same size as ____.
RBCs
3 Major Populations of Lymphocytes
- T lymphocytes
- B lymphocytes
- NK cells
____ are the maturation site for lymphocytes.
Primary Lymphoid Organs: Bone marrow and Thymus
____ are the activation site for the lymphocytes.
Secondary Lymphoid Organs: Spleen, Lymph Nodes, Appendix, Tonsils, MALT
Lymphocytes arise from the ____.
- Yolk sac
- Liver
Mature lymphocytes will only be activated with the presence of ____.
antigens
The ____ is considered the largest tissue of the body.
Bone marrow
The bone marrow has a total weight of ____.
1300 - 1500 g
The ____ is the main source of hematopoietic stem cells.
Bone marrow
B cells received their name because they were originally found to mature in birds in an organ called the ____.
Bursa of Fabricius
Bursa of Fabricius is similar to the ____ in humans.
appendix
The bone marrow is the main source of ____.
Hematopoietic Stem Cells
The ____ is the maturation site of the B-cells.
Bone marrow
The ____ functions as the center for antigen-independent lymphophoiesis.
Bone marrow
The bone marrow functions as the center for ____.
antigen-independent lymphophoiesis
The ____ is considered as an endocrine gland.
Thymus
Thymus secretes ____, which stimulates T-cell maturation.
Thymosin
What does Thymosin do?
Stimulate T-cell maturation
The ____ is a small, flat, and bilobed organ.
Thymus
The thymus weighs an average of ____ at birth.
30 g
The thymus weighs an average of ____ during puberty.
35 g
TRUE OR FALSE.
As we grow old, the thymus also gets bigger in size.
False
Reason: It gradually atrophies (lose cellularity)
Main parts of the Thymus
- Cortex
- Medulla
Which part of the Thymus contains thymocytes?
Cortex
The thymic cortex is where the ____ are found.
Thymocytes (immature T-cells)
Which part of the Thymus contains mature T-cells?
Medulla
The thymic medulla is where the ____ are found.
Mature T-cells
The ____ is the maturation site of the T-cells.
Thymus
Approximately ____ of the cortical cells die in the thymus before becoming a mature T-cell.
97%
____ is the process of lymphocyte production.
Lymphopoiesis
____ occurs in the secondary tissue.
Lymphopoiesis
Lymphopoiesis occurs in the ____.
secondary tissue
How does lymphopoiesis in the primary lymphoid organs differ from that of the secondary lymphoid organs?
- PLOs = antigen-independent
- SLOs = antigen-dependent
The ____ is the largest secondary lymphoid organ.
Spleen
The ____ acts as a lymphatic filter within the blood.
Spleen
The spleen has a size of ____ and weighs ____ in adults.
- 12 cm
- 150 g
The ____ is a large discriminating filter, as it removes old and damaged cells and foreign antigens from the blood.
Spleen
Two Main Types of Splenic Tissue
- Red pulp
- White pulp
Which Splenic Tissue?
Destroys old red blood cells
Red pulp
Which Splenic Tissue?
Contains lymphoid tissue, which is arranged around arterioles in a periarteriolar lymphoid sheath.
White pulp
White pulp is arranged around arterioles in a ____.
Periarteriolar Lymphoid Sheath (PALS)
Determine which location in the spleen
Where T-cells are found
Central arteriole
____ are found in the central arteriole of the spleen.
T-cells
Determine which location in the spleen
Where Naive (unstimulated) B-cells
Primary follicles
____ are found in the primary follicles of the spleen.
Naive (unstimulated) B-cells
Determine which location in the spleen
Where active B-cells are found
Secondary follicles
____ are found in the secondary follicles of the spleen.
Activated B-cells
Determine which location in the spleen
Where macrophages are found
Marginal zone
____ are found in the marginal zone of the spleen.
Macrophages
The ____ acts as a lymphoid filter in the lymphatic system.
Lymph nodes
____ allows contact between lymphocytes and foreign antigens from the tissues to take place.
Lymph nodes
The ____ are located along lymphatic ducts and serve as central collecting points for lymph fluid.
Lymph nodes
Lymph nodes serve as ____ for lymph fluid.
central collecting points
Surface of the lymph nodes
- Cortex
- Paracortex
- Medulla
Which region of the lymph node?
B-cell area
Cortex
____ are found in the cortex of the lymph nodes.
B-cells
Which region of the lymph node?
T-cell area
Paracortex
____ are found in the paracortex of the lymph nodes.
T-cells
Which region of the lymph node?
Differentiated cells and APCs
Medulla
____ are found in the medulla of the lymph nodes.
Differentiated cells and APCs
The lymph fluid flows slowly through spaces called ____, which are lined with macrophages, creating an ideal location where phagocytosis can take place.
sinuses
Numerous lymphocytes also enter the nodes from the bloodstream by means of specialized venules called ____.
High endothelial venules
____ is usually found in the gastrointestinal, respiratory, and urogenital tracts.
Mucosal-Associated Lymphoid Tissue (MALT)
MALT is usually found in the ____.
- Gastrointestinal tract
- Respiratory tract
- Urogenital tract
____ is the lymphoid tissue in the lower respiratory tract and hilar lymph nodes.
Bronchus Associated Lymphoid Tissue (BALT)
____ is associated with IgA production in response to inhaled agents.
Bronchus Associated Lymphoid Tissue (BALT)
BALT is associated with the production of ____.
IgA
____ includes lymphoid tissue in the intestines (Peyer’s patches of the appendix) and liver.
Gut Associated Lymphoid Tissue (GALT)
____ is important for the development of tolerance to ingested antigens.
Gut Associated Lymphoid Tissue (GALT)
____ is usually found on the epidermal cells that interact with the lymphocytes in the skin.
Skin/Cutaneous Associated Lymphoid Tissue
____ interact with lymphocytes in the skin and in draining lymph nodes.
Blood
____ acts as a reference in standardizing names of membrane proteins found on all white blood cells.
Clusters of Differentiation (CD)
____ are used to identify the stage of lymphocytes.
CD markers
CD markers specific for T-cells
- CD 3
- CD 4
- CD 8
Which CD marker?
Found on all T-cells; associated with T-cell antigen receptor.
CD 3
Which CD marker?
Identifies T-helper cells; also found in most T regulatory cells.
CD 4
Which CD marker?
Identifies cytotoxic T-cells
CD 8
CD markers specific for B-cells
- CD 19
- CD 21
Which CD marker?
Part of B-cell coreceptor; regulates B-cell development and activation.
CD 19
Which CD marker?
Receptor for complement component C3d; part of B-cell coreceptor with CD19.
CD 21
CD markers for NK cells
- CD 16
- CD 56
- CD 94
____ are cells that have not encountered their specific antigen.
Virgin or Naive Lymphocytes
____ are unstimulated cells.
Virgin or Naive Lymphocytes
____ are populations of long-lived T or B cells that have been stimulated by antigen.
Memory cells
____ can make a quick response to a previously encountered antigen.
Memory cells
____ carry surface IgG as antigen receptor.
Memory B cells
Memory B-cells carry ____ as antigen receptor.
surface IgG
____ have CD45RO, cell-adhesion molecules (CAMs), and chemical mediators.
Memory T cells
The ____ contained by memory T cells are involved during inflammatory process.
chemical mediators
____ have the capacity to produce harmful antibodies after differentiation into plasma cells.
B lymphocytes
____ have the capability to present antigen.
B lymphocytes
____ have the capability to expand clonally, which allows them to become dominant APCs.
B lymphocytes
____ produce a wide range of cytokines and chemokines that modulate maturation, migration, and function of other immune effector cells.
Activated B cells
Activated B cells produce a wide range of ____ that modulate maturation, migration, and function of other immune effector cells.
cytokines and chemokines
B lymphocyte subsets
- B1 cells
- B2 cells
____ is distinguished by the CD5 marker.
B1 cells
B1 cells are distinguished by the ____ marker.
CD 5
____ are a subset of B lymphocyte that generate autoantibodies.
B1 cells
____ account for most of the B-lymphocytes in adults.
B2 cells
____ generate a greater diversity of antigen receptors and responds effectively to T-dependent antigen.
B2 cells
The ____ is the first phase of B-cell development in the bone marrow.
Antigen-Independent Phase
Stages of Antigen-Independent Phase
- Pro-B cell
- Pre-B cell
- Immature B cell
- Mature B cell
____ require direct contact with the bone marrow stromal cells.
Progenitor B-cells
Progenitor B-cells require direct contact with ____.
Stromal cells
Which stage of B-cell differentiation?
A cytokine called Interleukin-7 (IL-7) is necessary at this stage.
Pro-B Cells
A cytokine called ____ is necessary at Pro-B cells.
Interleukin-7 (IL-7)
Which stage of B-cell differentiation?
Surface antigens: CD10, CD19, CD45R, CD43, CD24, c-Kit, Tdt, RAG-1 and RAG-2 genes
Pro-B Cells
Markers for Pro-B cells
- CD 10
- CD 19
- CD 45R
- CD 43
- CD 24
- c-Kit
- Tdt
- RAG-1
- RAG-2
Which stage of B-cell differentiation?
Rearrangement of genes that code for heavy and light chains of an antibody molecule occurs.
Pro-B cells
The rearrangement of genes in the Pro-B cells occur in ____.
Chromosome 14
Which stage of B-cell differentiation?
CD 19 appears early and remains on the B-cell until it differentiates into a plasma cell.
Pro-B cells
Which stage of B-cell differentiation?
The first heavy chains synthesized are the μ chains, which belong to the class of immunoglobulins called IgM.
Pre-B cells
Which stage of B-cell differentiation?
Surface antigens: CD10, CD19, CD20
Pre-B cells
Markers for Pre-B cells
- CD 10
- CD 19
- CD 21
In Pre-B cells, the first heavy chain synthesized are the ___.
μ chains
μ chains belong to which class of immunoglobulins?
IgM
Which stage of B-cell differentiation?
Contains pre-B cell receptor that is made up of 2 heavy chains and a surrogate light chain.
Pre-B cells
The ____ transmit signals to prevent rearrangement of any other heavy chain genes.
surrogate light chain
Which stage of B-cell differentiation?
B cell development is halted and cells are destroyed via apoptosis when gene rearrangement does not work.
Pre-B cells
What will happen when gene rearrangement does not work?
B-cell development is halted, and cells are destroyed by apoptosis
Which stage of B-cell differentiation?
Complete appearance of IgM molecules on the cell surface.
Immature B-cells
Which stage of B-cell differentiation?
Surface proteins: CD10, CD19, CD20, CD21, CD40, MHC class II molecules
Immature B-cells
Markers for Immature-B cells
- CD 10
- CD 19
- CD 20
- CD 21
- CD 40
- MHC Class II molecules
____ acts as a receptor for a breakdown product of the complement C3.
CD21
____ are important in the interaction of B cells with T cells.
CD40 and MHC Class II molecules
Which stage of B-cell differentiation?
B cells capable of producing antibody to self-antigens are deleted from the marrow via apoptosis.
Immature B-cells
____ refers to a programmed cell death.
Apoptosis
____ lead to autoimmunity.
Self-antigens
Which stage of B-cell differentiation?
In addition to IgM, the cells exhibit IgD.
Mature B-cells
Which stage of B-cell differentiation?
Surface proteins: CD19, CD20, CD21, CD40, CD81, CD225
Mature B-cells
Markers for Mature-B cells
- CD 19
- CD 20
- CD 21
- CD 40
- CD 81
- CD 225
Which stage of B-cell differentiation?
Presence of marginal and follicular B-cells.
Mature B-cells
____ remain in the spleen in order to respond quickly to any blood borne pathogens they may come into contact with.
Marginal B cells
____ migrate to the lymph nodes and other secondary organs.
Follicular B cells
Which stage of B-cell differentiation?
Central tolerance, or the elimination of B-cells that bear self-reactive receptors.
Immature B-cells
____ is the elimination of B-cells that bear self-reactive receptors.
Central Tolerance
____ exhibit identifying markers that include CD25.
Activated B-cells
____ acts as a receptor for IL-2, which is a growth factor produced by T-cells.
CD25
____ represents the most fully differentiated lymphocyte.
Plasma cells
The main function of plasma cells is to ____.
produce antibodies
____ represent 60-80% of the circulating lymphocyte.
T-lymphocytes
T-lymphocytes represent ____ of the circulating lymphocyte.
60-80%
____ are responsible for cellular immune responses and are involved in the regulating of antibody reactions in conjunction with B-lymphocytes.
T-lymphocytes
T-cell maturation is a complicated process that lasts for a period of ____.
3 weeks
Double Negative Stage
Early thymocytes lack ____.
CD 4 and CD 8 markers
Large DN thymocytes actively proliferate in the outer cortex under the influence of ____.
Interleukin-7 (IL-)
Large DN thymocytes actively proliferate in the ____ under the influence of interleukin-7.
outer cortex
Which stage of T-lymphocyte differentiation?
Large DN thymocytes actively proliferate in the outer cortex under the influence of interleukin-7.
Double Negative
Surface markers of DN thymocytes
- CD 2
- CD 5
- CD 7
- CD 45R
Rearrangement of the genes that code for the antigen receptor known as the T-cell receptor (TCR) begins at ____ stage.
Double Negative
Rearrangement of the genes that code for the antigen receptor known as the ____ begins at the double-negative stage.
T-cell receptor (TCR)
Which stage of T-lymphocyte differentiation?
Rearrangement of the genes that code for the antigen receptor known as the T-cell receptor (TCR) begins at this stage.
Double Negative
Which stage of T-lymphocyte differentiation?
Alpha and Beta chains which are seen on the variable region of the antibody.
Double Negative
The ____ is a combination of 8 chains.
CD3/TCR Complex
Which stage of T-lymphocyte differentiation?
____ is the main part of T-cell antigen receptor.
CD 3
The first chain to rearrange in the double negative stage is ____.
Beta chain
Six chains of the non-specific CD 3 portion
- Delta-epsilon
- Gamma-epsilon
- Tau-tau
____ have a different developmental pathway.
Gamma and Delta receptor
Which stage of T-lymphocyte differentiation?
Thymocytes express both CD 4 and CD 8 antigens
Double Positive
Which stage of T-lymphocyte differentiation?
A positive selection that allows only ____ with functional TCR receptors to survive.
Double Positive
Which stage of T-lymphocyte differentiation?
Any thymocyte that has either very low or very high affinity for self-antigen will die through a process called apoptosis.
Double Positive
Any thymocyte that has either very low or very high affinity for self-antigen will die through a process called ____.
apoptosis
Which stage of T-lymphocyte differentiation?
A negative selection takes place among the surviving double positive T-cells.
Double Positive
A ____ takes place among the surviving double positive T-cells.
negative selection
Survivors of selection exhibit only one type of marker, either ____.
CD 4 or CD 8
Mature T-cells will then migrate to the ____.
medulla
Approximately ____ of peripheral T-cells express CD 4 antigen.
2/3
Approximately ____ of peripheral T-cells express CD 8 antigen.
1/3
CD4+ subset
Helper-inducer T-cell
CD8+ subset
Suppressor-cytotoxic T-cell
T-Cell Subpopulation
Produce interferon gamma, interleukin-2, and tumor necrosis factor.
Th1 cells
T-Cell Subpopulation
Protect cells against intracellular pathogens by activating cytotoxic lymphocytes and macrophages (cell-mediated mechanisms).
Th1 cells
T-Cell Subpopulation
Including IL-4, IL-5, IL-6, IL-9, IL-10, and IL-13
Th2 cells
T-Cell Subpopulation
Help B-cells produce antibodies against extracellular pathogens and to generally regulate B-cell activity.
Th2 cells
T-Cell Subpopulation
Possess the CD4 antigen as well as CD25
T-regulatory (Treg) cells
T-Cell Subpopulation
Play an important role in suppressing the immune response to self-antigens.
T-regulatory (Treg) cells
T-Cell Subpopulation
Inhibit proliferation of other T-cell populations by secreting inhibitory cytokines.
T-regulatory (Treg) cells
T-Cell Subpopulation
The response of Treg cells are ____.
antigen specific
T-Cell Subpopulation
Produce IL-9 and appear to have proinflammatory effect
Th9 cells
T-Cell Subpopulation
Play a role at epithelial surfaces by warding off fungi and extracellular bacteria.
Th9 cells
T-Cell Subpopulation
Produce IL-17 and IL-22
Th17 cells
T-Cell Subpopulation
Both of its cytokines can increase inflammation and joint destruction
Th17 cells
T-Cell Subpopulation
Associated with autoimmune diseases
Th17 cells
____ are generally larger than T-cells and B-cells.
Natural Killer (NK) Cells
____ have the ability to mediate cytolytic reactions and kill target cells without prior exposure to them.
Natural Killer (NK) Cells
Surface markers of NK Cells
- CD 16
- CD 56
- CD 94
TRUE OR FALSE.
NK cells are part of the adaptive immunity.
False
Reason: They are part of the innate immunity.
____ represent the first line of defense against cells that are virally infected, cells infected with other intracellular pathogens, and tumor cells.
Natural Killer (NK) Cells
____ have the ability to recognize any damaged cell and to eliminate such target cells without prior exposure to them.
Natural Killer (NK) Cells
TRUE OR FALSE.
There is a balance between activating and inhibitory signals that enable NK cells to distinguish healthy cells from infected ones.
True
There is a balance between ____ that enable NK cells to distinguish healthy cells from infected ones.
activating and inhibitory signals
____ deliver inhibitory signals.
Inhibitory receptors
____ deliver signals to activate the cytotoxic mechanisms.
Activatory receptors
____ form channels (pores) in the target cell membrane.
Perforins
____ are packets of enzymes that may enter through the channels and mediate cell lysis.
Granzymes
Mechanism of Cytotoxicity
If there are no foreign substances, ____.
Inhibitory receptors will deliver inhibitory signal. Thus, there will be no killing of cells.
Mechanism of Cytotoxicity
If there are foreign substances, ____.
CD16 will immobilize the antibody and activate release of perforins and granzymes.
If there are foreign antigens encountered by NK cells, ____ will immobilize the antibody and activate release of perforins and granzymes.
CD 16
NK cells recognize and lyse antibody coated cells through a process called ____.
Antibody dependent cell cytotoxicity
Antibody Dependent Cell Cytotoxicity
Binding of antibody occurs through the ____ receptor for IgG.
CD 16
Antibody Dependent Cell Cytotoxicity
Binding of antibody occurs through the CD16 receptor for ____.
IgG
Laboratory Identification of Lymphocytes
- Density gradient centrifugation with Ficoll-Hypaque
- Flow Cytometry
- Fluorescence microscopy
- Rosette technique
Ficoll-Hypaque Specific Gravity
1.077 - 1.114
For Ficoll-Hypaque, ____ is used.
Diluted defibrinated or heparinized blood
____ is an automated system for identifying cells based on the scattering of light.
Flow Cytometry
In the ____, blood is incubated with the sheep’s red blood cells.
Rosette technique
In rosette technique, blood is incubated with the ____.
sheep’s RBC
In rosette technique, the sheep’s ebc will attach to the ____.
CD 2 antigen
CD 2 antigen is found only in ____.
T-cells
Which cell produces rosette?
T-lymphocytes
