(7-17) Adaptive Immunity -i- Flashcards
1. Differentiate between the primary response and the memory response. 2. Differentiate between humoral immunity and cellular immunity. 3. Identify the following types of cells: B lymphocytes, Plasma cells, Memory cells, T lymphocytes 4. Define: Antigen, Immunogen, Epitopes (antigenic determinants), Antibody 5. Describe the general structure of an antibody molecule and the functions of specific regions of the molecule. 6. List and describe six protective outcomes of antibody-antigen binding
What is adaptive immunity?
Each time the body is exposed to foreign material, the immune system learns to recognize and later remembers the most effective response for invaders.
What are the 2 basic strategies utilized in adaptive immunity?
- Humoral Immunity
~ B-cells & antibodies - Cellular immunity
~ T-cells
Which cell types are involved with Humoral Immunity and what do they eliminate?
- B-lymphocytes and antibodies
~ T-lymphocytes help out - They eliminate extracellular pathogens
What cell type is involved with cellular immunity and what does it eliminate?
- T-lymphocytes
2. Eliminate infra cellular pathogens
What were antigens considered initially and what does the term refer to today?
~ Originally, compounds that elicit antibody production (ANTIbody GENerator)
~ Today, it’s used to describe any compound that elicits an immune response
Which materials can constitute antigens, and what strength of responses do they induce?
Proteins and polysaccharides: strong response
Lipids & nucleic acids: weak
What is recognition of antigen directed at?
Antigenic determinant or epitope
How long does a primary response take?
A week or more (7-10 days)
What are antibodies, and how many regions do they have?
Y-shaped proteins with 2 regions.
Describe the 2 regions of an antibody.
- Constant region: the stem of the Y (Fc)
2. Two identical Variable regions: the arms of the Y
Which area if the antibody binds to an antigen, thus explaining the specificity of immunity?
Variable regions
What 6 things do antibodies do?
[C.A.N. I? O.K.]
- Complement activation
- Agglutination & Precipitation
- Neutralization
- Immobilization & prevention of adherence
- Opsinization
- directly Kill bacteria
What is neutralization (with respect to antibody action)?
Prevents toxin from interacting with cell
What is immobilization and prevention of adherence?
Antibody bonding to cellular structures to interfere with function.
What is agglutination and precipitation?
Clumping of bacteria with antibody to enhance phagocytosis
What is opsonization?
Coating of bacteria with antibody to enhance phagocytosis.
What is complement activation?
Antibody bonding triggers complement activation.
How do antibodies directly kill?
Antibody-dependent cellular toxicity (ADCC)
~ multiple antibodies bind a cell, which then becomes a target for Natural Killer (NK) cells
What type of cell do antibodies come from?
B-cells
How many B-cells does the human body have, and how many epitopes can each recognize?
- Human body has one billion B-cells
2. Each B-cell makes surface Ab that recognizes a single epitope
What happens when an antigen is introduced into the body?
The B-cell that makes the Ab to that particular antigen multiplies.
What is clonal selection and expansion?
Only the B-cell that makes the Ab to a particular antigen multiplies, so that the progeny of that B-cell all make identical Ab.
What 2 types of cells do B-cells differentiate into upon meeting an antigen?
- Plasma Cells
2. Memory Cells
What are Plasma Cells?
B-Cells that are specialized for massive Ab production
What are Memory Cells?
Long-lived B-cells that can respond to the same antigen quicker in the future
What are the 5 classes of antibodies?
- Immunoglobulin M (IgM)
- Immunoglobulin G (IgG)
- Immunoglobulin A (IgA)
- Immunoglobulin D (IgD)
- Immunoglobulin E (IgE)
What are the 4 characteristics of Immunoglobulin M?
- First Ab to respond to infection
- Secreted by plasma cells as a pentamer
- Very good at agglutination
- Initiates complement cascade well
What are the 4 characteristics of Immunoglobulin G?
- Plasma cells switch to making IgG after IgM
- Dominant Ab in circulation
- Only Ab that can cross the placenta
- The antibody of memory
What are the 2 characteristics of Immunoglobulin A?
- Found in secretions
~ ex. Breast milk, mucous, tears and saliva - Dimer
What is Immunoglobulin D?
IgD is a B-cell receptor
Which immunoglobulin is first to respond to infection?
IgM
What are the 2 cells that Immunoglobulin E attaches to, and in which 2 types of infection is it active?
- Found attached to basophils and mast cells
2. Active in parasitic infections and allergic
