Immuno 8: Effectors of Humoral Immunity Flashcards
Humoral immunity
Host defense mediated by secreted antibodies
Plasma cells
Antibody secreting B lymphocyte
Protective antibodies are produced during the _____ response to a microbe and in larger amounts during ________ responses
Protective antibodies are produced during the first (primary) response to a microbe and in larger amounts during subsequent (secondary) responses
Antibody production begins within [time frame] of vaccination
The first week
Memory B cell
Lies in wait. If it encounters antigen the rapidly diffentiate into antibody producing cells and start producing antibodies
Antibody region that binds to antigen
Fab region
Region of antibody that activates effector mechanism to eliminate antigen
Fc region
Changes that occur in antibodies produced by B cells
Class switching and affinity maturation
Neonatal Fc receptor (FcRn) location of expression and function
Expressed in placenta, endothelium, phagocytes and other cell times.
FcRn transports maternal antibodies to fetus circulation
How does maternal IgG avoid degredation in fetus
binds to FcRn and recycled back into circulation
Opsonization
Antibodies coat microbes to promote ingestion by phagocytes
Opsonin
Molecule that coats microbe to enhance phagocytosis
Phagosome
Vesicle formed from phagocytosis. Fuses with lysosome
Organ where phagocytes live and work
Spleen
Antibody-mediated phagocytosis is major defense mechanism against
Encapsulated bacteria
Population susceptible to encapsulated bacteria infection
Spleenless mfs
FcγRIIB
Fcy receptor that acts as anti inflammatory. Acts as feedback inhibition of B Cell activation
Fcy receptor of natural killer cells
FcyRIII (CD16)
Binds to IgG antibodies on cell surfaces (e.g. viral glycoproteins).
This causes granule release from NK cell which induces apoptosis
IgE normally binds to
worms
Three complement activation pathways
Alternative
Classic
Lectin
Alternative and lectin pathways are effector mechanisms of _______ immunity
Innate
Classical pathway is a mechanism of __________ immunity
Adaptive humoral
C3b
Complement system opsonin
C5 complement protein function
Intiates C5-6-7-8-9 membrane attack complex
C3a and C5a function to promote
Neutrophil chemotaxis, inflammation
C1 INH
Early stopper of complement cascade
Heriditary angioedema caused by ______
C1 INH defficiency
Increased proteolytic activation of bradykinin causes fluid leakage -> increased edema
Paroxysmal nocturnal hemoglobimuria
Unregulated complelement activation causes protein lysis
IgA produced in
Mucosal lymphoid tissues
IgA purpose
Binds to microbes to prevent them from colonizing through membranes
