adaptive immunity Flashcards
1
Q
adaptive immunity
A
-targets specific pathogen
-acquired thru infection of vaccination
consists of first and second response
2
Q
Humoral immunity
A
- produces antibodies (immunoglobulin) that combat antigens
- B cells = lymphocytes that are created and mature in bone marrow –> recognize antigens and make antibodies
- fight invaders outside cell
3
Q
cellular immunity
A
- produces T lymphocytes –> recognize antigenic peptides processed by phagocytic cells–> mature in thymus
- T cell receptors on T cell surface contact antigens, causing T cells to secrete cytokines or to kill presenting cell
- attack antigens that have already entered cell
4
Q
cytokines
A
- chemical messengers produced in response to a stimulus
1. interleukins = cytokines bt leukocytes
2. chemokines = induce migration of leukocytes
3. interferons = interfere with viral infections
4. tumor necrosis factor alpha = involved in inflammation of autoimmune diseases
-overproduction = cytokine storm
5
Q
antigens
A
- substances that cause production of antibodies
- usually component of invading thing
- can be protein, polysacchride, nucleoprotein, or glycoprotein
- usually on surface –> cell wall, pili, outer membrane, or flagella
- nonpathogenic antigens = pollen, egg whites, blood cell proteins
- epitopes = region that antibodies react with
6
Q
antibodies
A
- globular proteins called immunoglobulins
- super specific protein
- reacts with epitope of antigen
- 4 protein chains form Y shape –> 2 identical light chains and 2 heavy ones
- variable regions on end of arms bind epitopes
- constant region is stem which defines class
7
Q
IgG
A
- monomer
- 80% of serum antibodies
- in blood, lymph, and intestine
- cross placenta, trigger complement, enhance phagocytosis, neutralize toxins + viruses, bind pathogens
- 1/2 life = 23 days
8
Q
IgM
A
- pentamer made of 5 monomer held with J chain
- 6% of serum antibodies
- remain in blood vessels
- cause clumping of cells + viruses
- first responder to infection, but short lived
- 1/2 life = 5 days
9
Q
IgA
A
- monomer in serum; dimer in secretions
- 13% serum antibodies
- in mucous membranes, saliva, tears, and breast milk
- prevent microbial attachment to mucous membranes
- half life = 6 days
- initial line of pecific defense
10
Q
IgD
A
- monomer
- 0.02% serum antibodies
- structure similar to IgG
- in blood, lymph, and on B cells
- not really sure what they do
- 1/2 life = 3 days
11
Q
IgE
A
monomer
- 0.002% serum antibodies
- on mast cells, basophils, and in blood
- cause release of histamines when bound to antigen; lysis of parasytic worms
- 1/2 life = 2 days
12
Q
B cells
A
- from stem cells in bone marrow
- go to lymph nodes of spleen
- each has specific antibodies on its surface
- specific antigen binds to specific AB and stimulates B cell to divide + mature (activated)
- some turn into plasma cells –> secrete more AB to that antigen
- some B cells become memory cells –> long lived and easily activated
- some need reasurance by T helper cells
13
Q
Major histocompatibility complex
A
- genes that encode molecules on cell surfaces
- Class I MHC are on membrane of all animal cells and signal “self”
- Class II MHC are on surface of antigen presenting cells and trigger B cells
14
Q
How can B cells produce so many antibodies?!
A
Light chain has 200 V genes, 4 J genes, and 1 C gene = 800 combos
Heavy chain has 100 V genes, 4 J genes, and a bunch of C regions = 4800
together they make, like, 4 million combos
15
Q
Antigen-antibody complex
A
- tags ferein molecules for destruction
- agglutination = clumping
- opsonization
- antibody-dependant-cell-mediated-cytotoxicity
- neutralization = bind active site
- activation of complement system
