Pathology Week 3: Quiz 2: Diseases of the Immune System-Adaptive Immunity Flashcards
Content from "Week 3" PowerPoint
Involves a complex series of interaction between components of the immune system and the antigens (non-self) of a foreign pathogen.
The adaptation immune response (Adaptive Immunity)
What are antigens recognized by?
receptors on immune cells and secreted proteins
Cells then pass through the circulation to find homes in lymph nodes, mucosa-associated lymphoid tissue or the spleen.
Mature T cells
These cells migrate through the circulation to take up residence in an organ or they are “searching” for foreign antigen.
Small lymphocytes
The immunocompetent B cells respond to antigen presentation by doing what?
differentiation of B cells into active antibody-producing cells (plasma cells)
An example of immune cells being strategically located where they can serve as the first lines of defense against invading microorganisms, viruses and parasites.
The small intestine- they are perfectly positioned to interact with invading foreign substances and they recognize these substances as non-self or foreign. Upon such “recognition” lymphocytes are activated and function to neutralize or destroy the invading foreign substance.
What do the larger MALT components contain?
- B and T cell zones
2. Antigen processing cells
Distribution of MALT in the digestive system: Wall of Small Intestine
Aggregate lymphoid nodules
Main Lymphiod organs
Bone marrow and thymus
Examples of some types of T lymphocytes.
- T helper cells
- Cytotoxic T cells
- Suppressor T cells
Steps of the movement of lymph through the lymph nodes.
- Afferent lymphatic vessels branch outside the organ
- Penetrate the capsule
- Empty into the subcapsular sinus
- Lymph flows through cortical sinuses
- Contacts cells in the node cortex
- Flows through medullary sinuses> hilum> efferent lymphatic vessels
- Thoracic duct or right lymphatic duct
- Bloodstream
__________ move from the bone marrow into the thymus, take up residence and become thymus-dependent or _______.
Immature T lymphocytes, mature T lymphocytes
Is it possible by routine histological methods to differentiate the various types of small lymphocytes found in blood?
No
Steps of the movement of fluid through the spleen.
- Splenic artery carries blood
- Hilus (visceral surface)
- Into spleen
- Splenic vein takes blood-Leaves spleen through Hepatic portal system
- Lymphatics drain lymph from the spleen
Why do Lymph nodes occur in groups?
They group together where lymphatic vessels come together to form larger vessels.
Which Immunoglobulin: posses antiviral
IgG
What occurs to the thymus during involution?
Connective tissue fibers and fat cells replace the previously functional tissue.
Distribution of MALT in the digestive system: Wall of appendix
appendix
Where are groups of lymph nodes located?
- Groins
- Neck
- Axilla
Immunity that is transferred from another source.
Passive Immunity
Process of vaccines in humoral immunity
- Vaccine stimulates immune system to recognize antigen as foreign
- Destroy it
- Remember it
- Future memory response
Sites of B cell and T cell differentiation/storage.
Lymphoid Tissues
What do APCs present to in order to help to facilitate immune responses?
Helper T cells
Distribution of MALT in the digestive system: Wall of colon
Aggregate lymphoid nodules
Process of humoral immunity
- Antigen binds to B-cell receptors
- Antigen then ingested by B-cell
- B-cell presents antigen to T-cell
- B-cell produces antibody
These cells mature then move through the circulation to various sites throughout the body.
B lymphocytes
What type of cells dose the Adaptive Immune Response produce?
Antibodies (immunity) and lymphocytes
Which cells of the Adaptive Immune Response mature in the thymus?
T cells (Think-Thymus T)
The thymus is involved in this degenerative process by which it is very large in the first year or two of life, reaches maximum size at puberty, then becomes smaller.
Involution
What is the result of the process of involution in the thymus?
- A few pieces of functional tissue remain
2. These continue to supply sufficient number mature lymphocytes
Filters and purifies lymph.
Lymph nodes
Which Immunoglobulin: antibacterial and antitoxin properties
IgG
What does the type of T lymphocyte depend on?
Their specific role in the immune response.
Are there many types of T lymphocytes?
Yes
Mature antibody secreting cells.
Plasma cells
Which Immunoglobulin: the first antibodies made in acute infection
IgM
Ability of the Adaptive Immune System to identify to identify from non-self.
Tolerance
Adaptive or Innate Immunity? Passive
Adaptive
Which Immunoglobulin: helps differentiate B cells
IgD
These cells are mostly activated B lymphocytes.
Large lymphocytes
60% to 70% of the lymphocytes in peripheral blood
T cells
How is MALT similar to lymph nodes?
Pale-staining germinal center containing actively dividing lymphocytes
Upon interaction with foreign antigen (and often the help of T helper cells) B lymphocytes become what type of cells?
Plasma cells
Which Immunoglobulin: crosses the placenta and provides mother’s immunity to fetus
IgG
Example of naturally acquired humoral immunity
infection
After B lymphocytes move through the circulation to various sites throughout the body, they await interaction with what?
Foreign antigen and usually the assistance of T helper cells.
Consists of protection provided by cytotoxic T-lymphocytes that protect against virus infected or cancer cells.
Cell-mediated Immunity
Why is the exact extent of MALT aggregations of lymphocytes not easy to discern?
They have no distinct capsule (like lymph nodes)
What do all lymphatic vessels draining back to the venous circulation from the tissues have to pass through?
A lymph node
The product of long term specific protection (immunity) from particular invading microorganisms.
Specificity (has memory)
Example of Passive Immunity
Maternal IgG for first few months of life
Antigens must be “processed and presented” to the immune cells by what type of cell?
Antigen-processing cells (APCs)
What are the secreted proteins that recognize antigens
antibodies or immunoglobulins
Two different types of lymphocytes.
T lymphocytes (T cells) and B lymphocytes (B cells)
Where do some examples of MALT occur?
- Respiratory tracts
- Gastrointestinal tracts
- Urinary tracts
- Reproductive tracts
The functions of the spleen are similar to what other organs?
lymph nodes
Immune cells are strategically located where?
In areas that come in close contact with foreign substances.
Drain fluid (lymph) from peripheral tissues and bring it to the venous system.
Lymphatic Vessels
“replication” of an immune response to natural infection
Live attenuated vaccines
Example of artificially acquired humoral immunity
Vaccines
How is the large numbers of plasma cells needed to mount a good antibody (humoral immune) response provided?
Clones of plasma cells making specific immunoglobulins are produced.
Considered primary immune/lymphoid components because they contain the stem cells that will develop into T cells, B cells and natural killer cells of the functioning immune and lymphatic systems.
The bone marrow and thymus
Where is the spleen located?
B/w the stomach, left kidney and diaphragm
Which Immunoglobulin: Tags antigens for recognition
enters all tissues, see levels after the IgM, but then are present for subsequent exposures
Antibodies are also known as
Immunoglobulins
Consists of interstitial fluid that is similar to blood plasma but with a lower protein concentration, lymphocytes and macrophages
Lymph
Result of lack of self regulation by excessive immune response of the Adaptive Immune System.
Autoimmune
A temporary type of immunity that is transferred from another source.
Passive Immunity
Size of large lymphocytes.
9-15 µm
First lines of defense against invading microorganisms, viruses and parasites.
Immune cells
Immunocompetent T cells leave the thymus, go into the circulation and eventually find their way to where?
- lymph nodes
- mucosa-associated lymphoid tissue
- Spleen
Protective immune response that involves the activation of phagocytes, antigen-sensitized cytotoxic T cells and the release of cytokines and chemokines in response to an antigen.
Cellular Immunity
These cells function as antigen-presenting cells in the Adaptive Immune Response.
Macrophages and dendritic cells
Connective tissue located beneath mucous membranes in which the lymphocyte is the predominant cell type.
Mucosa-associated lymphoid tissue (MALT)
Functions of the Spleen
- Removes of abnormal blood cells and particulate matter (phagocytosis)
- Stores iron from recycled RBCs
- Initiates immune responses by B/T cells in response to antigens circulating in the blood
- Hematopoiesis in fetus (sometimes adult)
What do the smaller MALT components contain?
Mostly T lymphocytes
Which Immunoglobulin: enters all tissues
IgG
Protection provided by B lymphocyte derived plasma cells that produce antibodies that travel in the blood and interact with circulating and cell surface antigens.
Humoral Immunity
Which cells of the Adaptive Immune Response mature in bone marrow?
B cells (Think-Bone B)
Peripheral Lymphoid Organs
- Spleen
- Nodes
- Tonsils
- MALT
- Appendix
- Adenoids
Lima-bean shaped organs that are spread throughout the body but occur in groups.
Lymph nodes
Large lymphocytes represent what percentage of circulating lymphocytes?
3%
Where does lymph flow after processes in the lymph nodes?
Into the venous system.
What is the previously functional tissue of the thymus after involution called?
Parenchyma
Size of small lymphocytes.
6-9 µm
These cells help B cells to produce antibodies against protein antigens.
T lymphocytes
Which Immunoglobulin: protects mucosal tissues
IgG
Where is the Thymus located?
- Posterior to the sternum
2. Anterior part of the mediastinum
Result of lack of self regulation by inadequate immune response of the Adaptive Immune System.
Immunodeficiency
Which Immunoglobulin: instrumental in lysis of microorganisms
IgD
A bi-lobed nodular organ.
Thymus
Functions of the Lymph Nodes
- Filter debris/microorganisms (phagocytosis by fixed macrophages)
- Facilitate interaction b/w antigen presenting cells and circulating lymphocytes (to initiate an immune response)
- B lymphocytes: activation and proliferation; plasma cell formation and antibody production in response to antigens
- T lymphocytes: activation to become T helper and T cytotoxic cells
Which five cells are involved in Adaptive Immunity?
- Lymphocytes
- Macrophages
- Dendritic Cells
- Cytotoxic T-Lymphs
- Other Leukocytes
Which Immunoglobulin: see levels after the IgM, but then are present for subsequent exposures
IgG
These cells develop into effector cells of cellular immunity.
T lymphocytes
Adaptive or Innate Immunity? Cell- Mediated
Adaptive
System that includes the lymphatic vessels, lymphoid tissue and lymphoid organs, and Lymph nodes.
Lymphatic system
These cells recognize and responds to foreign antigens in the Adaptive Immune Response.
Lymphocytes
Immunity acquired through immunizations that is long lasting and provide a quick reaction.
Active Immunity
Ability of the Adaptive Immune System to identify antigens quickly.
Memory
Lymphocytes involved in humoral immunity.
B lymphocytes (B cells)
Which Immunoglobulin: Bind to mast cells and basophils to trigger histamine release and other inflammatory mediators
IgE
________ move from the bone marrow into the thymus where they become ________.
Immature T lymphocytes, immunocompetent T cells
Which Immunoglobulin: found in saliva, tears, colostrum, bronchial, GI, prostatic and vaginal secretions
IgA
Which Immunoglobulin: all inflammation, allergies, parasitic infections
IgE
Distribution of MALT in the digestive system: Wall of pharynx
Tonsils (palatine, lingual, pharyngeal)
Can the adaptive immune response react to a large or small number of microbes and pathogens?
Large
Which Immunoglobulin: provides local immunity on mucosal surfaces
IgA
Which Immunoglobulin: first circulating Ig to appear in response to an antigen
IgM
Adaptive or Innate Immunity? Humoral
Adaptive
Which Immunoglobulin: present in all body fluids
IgG
Substance foreign to the host that stimulate an immune response.
Antigen
Secondary response of humoral immunity
boost or intensify response
Lymphocytes involved in cell-mediated immunity.
T lymphocytes (T cells)
Primary response of humoral immunity
immunity without disease
Why do Antigen-processing cells present the antigen?
So immune cells are able to react with them
Can the adaptive immune response distinguish between self and non-self?
Yes
These cells function as effector cells in the Adaptive Immune Response.
Cytotoxic T-lymphs, macrophages, and other leukocytes
Rarely found in the circulation but reside mostly in connective tissue (lamina propria) beneath epithelia, in the medullary cords of lymph nodes and in the white pulp of the spleen.
Plasma cells
Largest lymphoid organ in the body that is a soft organ, conforming to the contours of the organs and structures surrounding it.
Spleen
Where are the smaller, more scattered, MALT located?
Intestines and respiratory tract
Where do the two different types of lymphocytes originate from?
Stem cells in bone marrow
An essential property of the immune system.
Self regulation
Distribution of MALT in the reproductive system
In the wall of the vagina
How does Maternal IgG provide immunity to fetus?
Crosses placenta and provides mother’s immunity to fetus
Immunoglobulins
IgG, IgA, IgM, IgD, IgE
Which Immunoglobulin: prevents attachment to epithelial cells by invaders
IgA
The immunocompetent T cells respond to antigen presentation by doing what?
differentiation of T cells into effector cells (cytotoxic T cells)