Immunology Flashcards
What are the three branches of immune response?
Innate, intrinsic, adaptive
What is unique about adaptive immunity?
Provides memory and specificity
What is superoxide?
O2-, incredibly reactive, destroys lipid
What does superoxide dismutase do?
Turns reactive material into water
Is respiratory burst an oxygen-dependent action?
Yes
What types of cells/materials carry out oxygen-independent killing?
Low molecular weight defensins, cathepsin G, lysozyme, lactoferrin, proteolytic and/or hydrolytic enzymes
What is the purpose of C3B in the complement cascade?
Binds to invader so the system can “see” it
What is the purpose of C3A in the complement cascade?
Promotes inflammation
What is DAF and what does it do?
Decay accelerating factor, prevents continuation of complement cascade (Useful in transplantation)
What does antigen presentation cause the expansion of?
B cells producing antigen-specific antibody, and cytotoxic T cells that can lyse infected cells
How is specificity brought to the immune system?
Through antibodies
How does the time for IgM and IgG responses differ between an initial infection and a secondary infection?
IgM quick to respond in first infection as IgG creates specific antibodies, in second infection IgG is first to respond with cells that remember the initial infection
Why is TRIM5alpha special to intrinsic immunity?
Resistant to HIV, recognizes all viruses in a family and destroys the virus as soon as it enters a cell
What parts of an immunoglobulin make up the antigen binding site?
Light and heavy chains
Why is a constant domain important in an immunoglobulin?
So that the body can recognize it as “self”
In terms of an immunoglobulin, what do V, D, and J stand for?
Variable region, diversity, joint region
How are the heavy and light chains connected to each other?
Disulfide bonds
What do the FAB region and Fc region stand for?
Fragment antigen binding, Fragment crystallizable or Fragment constant
What are the three types of antibody variation?
Idiotypic (Change in antigen-binding site), allotypic (Change in AA sequence of heavy or light chain, inherited), isotypic (Change in light/heavy chain classification)
What are the possible types of light chains in antibodies?
Kappa or lambda
What are the possible types of heavy chains in antibodies?
Mu, Alpha, Delta, Gamma, Epsilon
What is the name of the site where antigens bind to anibodies, and which type of of site is more effective (Linear or conformational)?
Epitope, conformational (Normally live attenuated vaccines)
Name some features of IgG.
Secondary response to antigen, binds Fc region, neutralizes antigen and fixes complement (Signals for phagocytosis), high affinity due to affinity maturation
What three antibodies are transferred to offspring through colostrum?
IgG (Most), IgA (Intermediate), and IgM (Least)
Name some features of IgM.
Most primitive antibody, first responder to invasion, pentameric, low affinity but high avidity, neutralizes antigen and fixes complement
Name some features of IgA.
Most abundant in the body, can be dimeric or trimeric, heavy glycosylated hinge region, found in mucosal epithelium, has a secretory component, must be able to resist proteolytic degradation
Name some features of IgE.
Triggers histamine release (Regulate allergic responses) and mast cell degranulation, are present on the surface of mast cells, coats parasites and causes basophils/eosinophils to burst on parasite
Name some features of IgY.
Found in water birds (And a few other species), descendant of IgG and IgE, has no Fc region (Thought to cut down on allergies)
How does IgG differ in camelids?
Many only have a heavy chain which helps the molecule fit in tighter areas
Where do antibodies originate from?
B cells
Name some stages in the development of the plasma cell.
Hematopoietic stem cell, lymphoblast, lymphocyte, plasma cell
How are B cells selected for a specific antigen?
We make B cells against all known antigens, choose the one that works for a specific antigen, and get rid of the rest
What do plasma cells do?
Produce protein/antibodies (Have ER for protein production)
What is the fate of most virgin B cells?
Apoptosis in over 75%
Where does B cell variable region rearrangement occur to give rise to specificity?
Bone marrow
Once DNA is arranged, how is an antibody changed to improve affinity (NOT specificity)?
Can only be changed through the heavy chain
Name some features of class (Isotype) switching of antibodies.
Cannot switch back once a switch has occurred (Can go from IgM to IgG but not IgG to IgM), variable region sits right in front of the expressed class, when switching occurs the regions for other classes are excised away, occur in lymph follicles
How does IgM aid the production of IgG?
IgM provides time for the body to produce IgG
How do B cells react to a primary exposure to an antigen?
Produce plasma cells for antibody production and also start a B cell memory pool
How do booster work?
Given after the first vaccine has given the body enough time to weed out unsuitable B cells
How do B cells react to a secondary exposure to an antigen?
Call more memory cells and plasma cells to the area very quickly and in high amounts
What cells can be antigen presenting cells?
Macrophages, follicular dendritic cells, and B cells
Name some characteristics of clonal immune response.
Germline, same DNA in all cells from the line, labs measure DNA rearrangement, can be dangerous
Name some characteristics of polyclonal immune response.
Reactive, non-malignant, from a wide range of DNA
How do B cells get in and leave the lymph node?
Come in through blood vessel, circulate out through efferent pathway