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