Immunology Flashcards
The cells and molecules responsible for immunity, and their collective and coordinated response to the presence of foreign substances.
Immune System
The overall actions of the immune system to provide immunity through a sequence of integrated host defense events when a host encounters a “foreign” substance and leading to cellular and chemical defensive actions.
Immune Response
The body’s resistance to disease-causing microorganisms and damage by foreign substances.
Immunity
Natural/native immunity. Non-specific, general recognition & response to “foreign” substances, including inflammatory response.
Innate Host Response
The route of transmission & microbe type determine nature of response.
Innate Host Response
This is the acquired/induced response
Adaptive immunity
Adaptive Response is _____ to “foreign” substances.
Specific
Pre-committed lymphocytes in the lymph nodes and spleen respond against the “foreign” substance
Adaptive immunity
A foreign substance, such as a microorganism, foreign blood cell, cells of transplanted organs, or toxins.
Antigen (Ag)
What triggers an immune response when introduced into the body?
Antigen (Ag)
What is the basic molecule of an antibody?
Y shaped
Antibody portion that is antigen-specific, and binds to a specific site on antigen molecules and assists in inactivating the antigen by attaching to it.
Fragment Antigen-Binding (Fab)
Part of the antibody that can bind to a phagocytic cell.
Fc portion
What is categorized into classes: Ig A, Ig D, Ig E, Ig G, Ig M?
Antibody (Ab) [immunoglobulin Ig]
Antigen specific proteins
Antibody (Ab) [immunoglobulin Ig]
What do phagocytes do?
ingest and digest invading microbes
- Ingestion
- Digestion
- Waste
Phagocytes are certain _____ blood cells
white
Specialized cells located in various tissues that help initiate the immune response by recognizing, “processing”, and presenting Ag to other cells of the immune system
Dendritic cell
Where do stem cells originate?
Bone marrow
About how many erythrocytes are there per mcL?
4-6 million
About how many leukocytes are there per mcL?
4,500-11,000
Which white blood cells are involved in the inflammatory process?
Basophiles (0.5-1%)
Which white blood cells increase in allergic responses?
Eosinophils (1-5%)
What are the primary phagocytic cells that ingest/kill foreign material?
Neutrophils (45-75%)
About how many hours do neutrophils circulate for?
6-10 hours
What do neutrophils do after they circulate in the blood?
adhere to the endothelium of the blood vessels and wait to respond to inflammation; short lived.
What matures into macrophages & dendritic cells and responds to inflammation signals?
Monocyte (2-8%)
What are precommitted during maturation to respond to specific antigens?
Lymphocytes (25-40%)
What are the types of lymphocytes?
T-cell, B-cell, and Natural Killer Cell
Approximately, how many lymphocytes are produced per day?
10^9
The average lymphocyte completes a cycles of circulation through the blood and lymphatic system in about how many days?
1 to 2 days
What percentage of total body lymphocytes are present in the circulating blood?
About 1%
Where are the lymphocytes that are not circulating in the blood (the other 1 %)?
adhered to the inside of blood and lymphatic vessels until needed during infection.
What are the large phagocytic cells that mature from monocytes?
Macrophages
These are about 10 times the size of monocytes
Macrophages
These are a major phagocytic cell but not as numerous as neutrophils
Macrophages
Possess many broad-specificity receptors enabling it to capture a wide range of pathogens and can serve as Antigen-Presenting Cells (APC).
Macrophages
What is a major line of defense against invading microbes and abnormal or defective host cells?
Macrophages
Tissues where antigens interact with cells of the immune system
Lymphoid Tissues
Where are pieces of the antigen processed through in a “percolating/meandering” manner?
lymph nodes or spleen
A site containing lymphatic fluid that responds to local or regional infection?
Lymph Nodes
Blood-borne antigens and Antigen-Presenting Cells meander through which organ where they encounter and activate precommitted lymphocytes?
Spleen
Site that responds to systemic infections?
Spleen
MALT
Mucosal-Associated Lymphoid Tissue
GALT
Gut-Associated Lymphoid Tissue
Appendix and Peyer’s patches, lymphoid nodules on outer wall of intestines
GALT
Bronchus-Associated Lymphoid Tissue
BALT
What are some other Non-thymic Lymphoid Tissue?
MALT, GALT, BALT, Tonsils
What stimulates an immune response and reacts/binds with antibodies or T-cell receptors?
Antigen (Ag)
What are the characteristics of an antigen?
- Substance appears foreign to the host’s immune system
- Size- relatively large molecule
- Chemical nature- usually protein with complex 3-D configuration
- Antigenic determinant
What is the usual molecular weight of an antigen?
more than 10,000
What are some factors that affect the ability or quality of a molecule to be a good immunogen?
Route, quantity, timing, and ability to degrade
The specific part of the immunogen that specifies or determines the exact antibody to be produced
Epitope
The epitope is the portion of the antigen that combines with?
A specific antibody or T-call receptor
What will induce the production of slightly different antibodies?
Different epitopes (even on the same antigen)
The quality of the epitope is based on what?
The exposure to the immune system and the 3-dimenstional shape of the molecule.
What are the Major Histocompatibility Complex proteins (MHC)?
proteins on the surface of tissue and blood cells which identify cells belonging to a specific individual.