Recognition and Response Flashcards
All cells receive and respond to signals, but immune cells must:
A. Interact with pathogens
B. Eliminate pathogens
C. Communicate via signal transduction
D. All of the above
D. All of the above
Receptor-ligand binding occurs through multiple (______) bonds that allow sufficient binding.
A. covalent
B. noncovalent
C. ionic
B. noncovalent
What is the strength and affinity of each ligand-receptor bond?
Strength: weak bond
Affinity: strong affinity
Define affinity.
strength of individual bond
Define avidity. What increases avidity?
Avidity: combined binding strength of multiple interactions
- multivalency increases avidity
What 4 molecular changes does ligand-receptor binding induce?
- conformational change
- dimerization (cluster)
- location on membrane
- covalent modification (phosphorylation)
What 3 intracellular events do receptor alterations induce?
- gene transcription
- enzyme activation (kinases)
- protein location changing
List two common features of immunoglobulins.
- immunoglobulin (Ig) domains
- can be located on the transmembrane, cytosol, or secreted
Pattern Recognition Receptors (PRRs) are expressed by (_____) and recognize (______).
innate immune response; PAMPs/DAMPs
B-cell Receptors (BCRs) are expressed by (______) and recognize/bind to (______) antigens.
B-cells; soluble
T-cell Receptors (TCRs) are expressed by (______). They are specific for (______) derived antigens from antigen-presenting cells on (_____) molecules.
T-cells; peptides; MHC
Cytokine Receptors are expresses by all (______) cells and recognize (______).
immune; cytokines
Chemokine Receptors are expresses by all (______) cells, recognize (______), and have (______) coupled-receptors.
immune; chemokines; G-protein
PRRs are our innate immune response that produce which of the following to educate the adaptive immune response?
A. cytokines/chemokines
B. B-cells/T-cells
C. immunoglobulins/amino acids
A. cytokines/chemokines
How many classes of PRRs are there?
5
The B-cell receptor is structured with two heavy chains and two light chains. Name the fragments and functions.
Light chains = Fab
- antigen binding fragment
- antigen specificity
Heavy chains = Fc
- constant fragment
- antibody effector activity
What are the 5 effector antibodies identified on the Fc region of the heavy chain?
- Ig(α) alpha: 4 binding sites
- Ig (Δ) delta: 2 binding sites
- Ig (ϵ) epsilon: 2 binding sites
- Ig (γ) gamma: 2 binding sites
- Ig (μ) mu: 10 binding sites
Which immunoglobulins (antibody effectors) form a BCR complex?
- Ig(α)
- Ig(β)
How do immunoglobulins (Ig) on BCRs transduce signals?
ITAMS
TCRs have peptide sources from (______) or (______) processed antigens.
A. endogenously; exogenously
B. intracellular; extracellular
C. Both are correct
C. Both are correct
What are the coreceptors for TCRs? Which one contains ITAMs to transmit signals?
Coreceptors:
- CD4 (Thelper, MHC II, exogenous)
- CD8 (Tcytotoxic, MHC I, endogenous)
- CD3 (ITAMs)
- CD28 (activates naive T-cell)
T/F. Cytokines are proteins that communicate in the immune system.
True
What 3 types of extracellular signaling do cytokines mediate?
- Endocrine (insulin)
- secreted by signaling cells
- affect DISTANT receptor-expressing target cells - Paracrine (neurotransmitters)
- affect only NEARBY receptor-expressing target cells - Autocrine (growth factors)
- cells respond to signals they secrete
Describe this property of cytokines/chemokines.
- induces different biological effects dependent on target cells
