9.29 Immunity 3 Flashcards
What is an antigen?
- foreign substance that enters the body
- bacteria, virus, parasite, etc.
What is an epitope?
a subunit of an antigen
- immunologically active site on the antigen that binds to a t-cell receptor
- creates an antigen response with antibody
How do immune cells recognize self?
- cell markers are unique to individual antigen
- cell markers determine which antigen to respond to and how strong
- cell markers allow communication between immune cells
What are antigens?
Y-shaped molecules with 2 antigen binding sites
Antibodies are produced by:
B cells
Antibodies consist of
2 identical heavy (H) and light (L) chains
The H chain includes
4-5 immunoglobulin domains
L chains are bound to
H chains
What are the other regions that do not contain antigen binding sites known as?
constant regions
What are immunoglobulins?
globulins with antibody activity
major functions of immunoglobulins?
- directly attack antigens by destroying and neutralizing
- activate complement system
- activate anaphylaxis by releasing histamines
- stimulate antibody-mediated hypersensitivity
Generation of diversity occurs through _______, resulting in _______ different types of immunoglobulins.
- gene rearrangement
- 10^9 to 10^11
MHC =
major histocompatibility complex
MHCs are how the body does this:
seeks out invaders and initiate a response
What is an MHC?
- a group of protein markers found on cell membranes
- promotes the immune system to recognize its own cells and distinguish them from foreign pathogens
Types of MHCs
- Class I: endogenous/cytosolic
- Class II: exogenous/endocytic
Where are Class I MHCs found? What are they used for?
- found on membranes of almost all of our cells
- used to differentiate between healthy and infected cells?
Where are Class II MHCs found? What are they used for?
- found on specific immune cells such as B cells, macrophages, and T cells
- help immune cells communicate with each other via the extracellular environment
T-cells recognize when:
something isn’t supposed to be there
What are the categories of adaptive immune response?
- cell-mediated (T-cell immunity)
- humoral (B-cell immunity)
T cells and B cells both originate in
bone marrow
Cell mediated immunity (t-cell)
T lymphocytes travel from bone marrow to thymus to learn how to differentiate self from non-self
humoral immunity (b-cell)
B lymphocytes produce 5 Ig molecules
What are the Ig molecules produced by B lymphocytes?
- IgG
- IgM
- IgA
- IgD
- IgE
