Look a rainbow! Do me on it Flashcards
The largest physical barrier to be defended are the mucous membranes. T/F?
true
Commensal microbiota in the gut compete with pathogens for nutrients and attachment sites. T/F?
true
Lysozyme, defensins, cathelicidins and histatins are all examples of what?
antimicrobial enzymes/peptides
Thick or impaired mucus flow predisposes an individual to what?
chronic infection
What cells of the immune system are prolific cytokine factories?
T helper cells
What cell acts as a liaison between the innate and adaptive immune systems?
dendritic cell
Inflammation is an ADAPTIVE immune cell response. T/F?
false (innate immune cell response)
What is NOT a function of antibodies?
Apoptosis
Natural Killer cells and killer T cells do that
What ARE functions of antibodies?
Neutralization
Opsonization
Compliment activation
What function of antibodies “tags” a cell for destruction?
Opsonization
What is NOT a function of the complement system?
Antigen presentation (Macrophages, dendritic cells and B cells do that)
Is the complement system phagocytic?
NO
What is the function of C3a and C5a?
Chemoattractant
What is the function of C5b?
Form membrane attack complexes
What is the function of C3bBb?
Convertase (split more C3 and C5)
What is the function of C3b?
bind to the cell membrane
What is the most numerous WHITE blood cell in the blood?
Neutrophil (50-70%)
What is the most numerous RED blood cell in the blood?
Erythrocyte
What monosaccharide found on the surface of many pathogens can trigger the activation of complement?
Mannose
What professional phagocyte normally circulates in the blood?
Neutrophil
What professional phagocyte normally circulates in tissue?
Macrophage (circulate as monocytes)
What is a precursor for dendritic cells?
Monocytes
What is NOT characteristic of a primed macrophage?
Major producer of TNF
hyperactive macrophage characteristic
What are the 3 stages of macrophages?
- resting
- primed
- hyperactive
What is up-regulated by an activated neutrophil and binds to endothelial ICAM allowing the neutrophil to stop?
Integrin
What is expressed by endothelial cells and binds to selectin ligand?
selectin
What is expressed on the surface of neutrophils?
selectin ligand
Natural killer cells kill by what mechanism?
Apoptosis
Necrosis is what type of immune response?
inflammatory
NK cells bind what antibodies to allow it to kill via antibody dependent cellular cytotoxicity?
IgG
What is the most Abundant antibody class in the human BODY?
IgA
What antibody is released in response to allergiEs?
IgE
What is the first and largest antibody produced following antigen recognition?
IgM
All B cell receptors (tethered antibodies) on any given B cell are identical. T/F?
true
Besides a B cell receptor on a B cell, name another type of receptor that would likely be present.
Compliment receptor
Mast cells binding what antibody will cause mast cells to degranulatE?
IgE
Which antibody is most commonly found in a mother’s breast milk?
IgA
Which antibody can confer passive immunity from the mother to the fetus and crosses the placenta?
IgG (most abundant antibody in the BLOOD)
What enzyme do mast cells release during degranulation?
histamine
In consideration of the heavy chain modular design, which gene segment has the MOST variations ( ~ 40) to choose from?
V (MOST)
In consideration of heavy chain modular design, what is the function of the B cells?
“cut and paste” different constant regions
In consideration of the heavy chain modular design, which gene segment has the LEAST variations ( ~ 6) to choose from? Which segment has ~ 10 variations? ~25?
J = 6 (LEAST) C = 10 D = 25 V= 40 (MOST)
What is expressed on an NK cell that binds to a Fas protein on the invader, triggering apoptosis?
Fas ligand
What is the function of Perforin?
Pokes a hole in the membrane, injects enzymes which trigger apoptosis
In a B cell receptor, what is the function of Igα and Igβ?
- **sends an activation signal to the nucleus
- attaches the receptor to the cell membrane
What is the function of disulfide bridges?
bind the heavy chains together
In an antibody, what is the function of the paratope?
Bind to the epitope, part of the antigen
Almost all cells in the body express MHC I. T/F?
true
MHC II is typically found with which cells in the body?
antigen presenting cells
What 3 types of Antigen Presenting Cells (APCs) express MHC II?
Activated dendritic cells
Activated macrophages
Activated B cells
The helper T cell co-stimulates the B cell by expressing what?
CD40 ligand
After a B cell has found its cognate antigen and proliferates, most of these proliferating B cells become what?
Plasma cells
What cells are considered “antibody factories” and are found in the spleen or bone marrow?
Plasma cells
What are 3 functions/characteristics of IgA?
- unable to fix complement
- found in mother’s milk
- can coat pathogen and prevent mucosal attachment
What is the result of B cell activation without T cell help?
can ONLY produce IgM (default antibody class)
What is the most abundant antibody in the BLOOD?
IgG
What antibody typically targets parasites?
IgE
What normally prevents endogenous peptides from loading onto MHC II?
Invariant chain
Stimulation of what nerve(s) can attenuate or inhibit inflammation mediated by splenic macrophages?
Vagus nerve
All antigen presenting cells express B7 co-stimulatory proteins. T/F?
true
What is the function of MHC I?
Displays endogenous peptides
What is the function of MHC II?
Displays foreign (exogenous) peptides
Which MHC on average can display longer peptides? How many AA for each?
MHC II = 13-25 AA
MHC I = 8-11 AA
B7 displayed on macrophages can act as a co-stimulatory molecule to the antigen presenting MHC. What receptor on the B cell binds B7?
CD28
Toll-like receptors are best described as which of the following?
Pattern recognition receptors
What antigen presenting cell, phagocytizes antigen at the battle site, displays it on MHC II and travels back to a lymph node to activate T cells?
Activated dendritic cells
What is the major antigen presenting function of activated macrophages?
re-stimulate T cells at the battle site
What is the major antigen presenting function of activated dendritic cells?
re-stimulate T cells at the lymph node
What is the major antigen presenting function of activated B cells?
concentrate antigen
What antibody is the major mucosAl antibody, can bind to pathogens in the gut and prevent attachment (neutralization) to mucosAl cells?
IgA (does not fix complement)
What substance is released from degranulating mast cells and is associated with anaplylactic shock systemically?
Histamine
What 2 substances are released by helper T cells?
interferon and IL-1 (cytokines)