Week 1 Flashcards
Edward Jenner used what to vaccinate against smallpox in 1796?
cowpox
which virus did dmitri ivanosky discover?
tobacco mosaic virus
what did both Iilya Iiyich Mechnikov and Paul Ehrlich receive in 1908?
Noble prize
where do dendritic cells originate from?
lymphoid progenitor
T/F the mucous membrane covers more surface area than the skin
True
what do cilia do in the lungs?
remove microbes and debris
what are the three main types of phagocytes?
macrophages, neutrophils, and dendritic cells
what does a macrophage use to draw in foreign objects to “eat” them?
pseudopod
explain how chemotaxis occurs in a neutrophil
when a neutrophil SENSES something to engulf it becomes POLARIZED which causes CHEMOTAXIS where the neutrophil is attracted to the thing it wants to engulf and can track it down to ingest it
what are the two adaptive immunity cells called?
T lymphocytes and B lymphocytes
what mainly comprises our innate immunity?
- epithelial barriers
- phagocytes
- complement system
- NK cells
humoral immunity is mediated by _ lymphocytes and is the mechanism of defense against ______ ______
B
extracellular microbes
Cell-mediated immunity is mediated by _ lymphocytes and their products, such as _____ and is the mechanism of defense against _________ ______
T
cytokines
intracellular microbes
explain what passive immunity is
transferring of antibodies or effector cells
_______ are the only cells capable of specifically recognizing antigens and are thus the principal cells of adaptive immunity
Lymphocytes
Antigen-presenting cells capture microbial antigens, they display them to be recognized by _______
lymphocytes
what cell type do lymphocytes differentiate into to eliminate antigens?
effector cells
__________ help macrophages to eliminate ingested microbes and help B cells to produce antibodies.
CD4+ helper T lymphocytes
_________ kill cells harboring intracellular pathogens, thus eliminating reservoirs of infection
CD8+ CTLs
antibodies are the products of?
B lymphocytes
pathogen-associated molecular patterns (PAMPS) are a part of ____ immunity
innate
what are the three kinds of receptors in innate immunity?
a. Toll-like receptor
b. S-methylamine receptor
c. N-formyl methionyl receptor
d. Risperidone receptor
e. Mannose receptor
a,c,e
what are the two kinds of receptors in adaptive immunity?
Ig receptors
TCR receptors
name the three Cytosolic pattern recognition receptors and what they do
- RIG-like receptors (RLRs): recognize viral RNA
- cytosolic DNA sensors (CDSs): recognize bacterial cell wall constituents and also sense intracellular crystals, reactive oxygen species
- NOD-like receptors (NLRs): same recognition as CDSs
pattern recognition factors, such as TLRs and RLRs, signal to activate the transcription factors ____ and _____ which promote inflammatory gene expression
NK-kB
AP-1
pattern recognition factors, such as IRF transcription factors, stimulate expression of the antiviral _________
type I interferon genes
what is the inflammasome composed of?
NOD-like receptor, an adaptor, and the enzyme caspase-1
what is the main role of the inflammasome?
produce active forms of the inflammatory cytokines IL-1 and IL-18
explain what NK cells do
defend against intracellular microbes and provide a source of the macrophage-activating cytokine IFN-γ
what prevents an NK cell from attacking normal human cells?
class I MHC molecules
why does the complement system activate on microbial surfaces and not on normal host cells?
because microbes lack regulatory proteins that inhibit complement
what are the The two major effector functions of innate immunity?
induce inflammation and block viral infection
TNF and IL-1 are cytokines that do what?
activate endothelial cells, stimulate chemokine production, and increase neutrophil production by the bone marrow.
L-1 and TNF both induce the production of what other cytokine?
IL-6
IL-12 and IL-18 are cytokines that do what?
stimulate production of the macrophage-activating cytokine IFN-γ by NK cells and T cells
which two precursors of tissue macrophages migrate from blood into inflammatory sites during innate immune responses because of the effects of
cytokines and chemokines produced by PAMP- and DAMP-stimulated tissue cells?
Neutrophils and monocytes
IL-10 is a cytokine that is produced by and inhibits activation of ____ and ____
macrophages
dendritic cells
what is the name of the drug which is a candidate for treatment and prevention of covid-19?
Apilimod
what does Apilimod do specifically?
blocks replication of covid-19 virus in pneumocyte-like cells
explain how a naive T cell becomes an effector T cell
Naive T cell binds to a dendritic cell which gives it the information required to become an effector T cell. The Naive T cell becomes activated and differentiates into an effector T cell
Effector T cells activate two other types of cells. What are these cells and what is the outcome?
Macrophages: kill microbes specified to info received from effector T cell
B cells: produce antibodies in response to info received from effector T cell
what is the difference in recognition between CD4+ helper T lymphocytes and CD8+ CTLs?
CD4+ recognizes antigens in association with class II MHC gene products whereas CD8+ recognize antigens in association with class I MHC gene products
dendritic cells, macrophages, and B lymphocytes, capture extracellular protein antigens, internalize and process them, and display class __-associated peptides to ____ cells
II
CD4+ T
Class I MHC molecules are composed of?
an α chain complexed with β2-microglobulin
Class II MHC molecules are composed of?
two MHC-encoded polymorphic chains, an α chain and a β chain
Both classes of MHC molecules consist of:
a. extracellular peptide-binding cleft
b. non-polymorphic Ig-like region
c. β polymorphic chain
d. transmembrane region
e. nucleoplasm region
f. cytoplasmic region
a,b,d,f
The peptide-binding cleft of MHC molecules has (two answers):
a. β-helical sides
b. α-helical sides
c. eight-stranded antiparallel β-pleated sheet floor
d. double-stranded antiparallel β-pleated sheet floor
b,c
The polymorphic residues of MHC molecules are localized to?
the peptide-binding domain.
what is the function of class I and class II MHC molecules?
bind peptide antigens and display them for recognition by antigen-specific T lymphocytes
which MHC class allows larger peptides to bind?
class II
what do cytokines like IFN-γ do?
stimulate the transcription of MHC genes
TLR1 recognizes?
a. CpG DNA
b. ssRNA
c. Bacterial lipopeptides
d. LPS
c
TLR2 recognizes?
a. CpG DNA
b. bacterial lipopeptides
c. LPS
d. bacterial peptidoglycan
e. b and d
f. a and b
g. c and d
e
TLR3 recognizes?
a. LPS
b. dsRNA
c. ssRNA
d. CpG DNA
b
TLR4 recognizes?
a. dsRNA
b. LPS
c. CpG DNA
d. ssRNA
b
TLR5 recognizes?
a. Bacterial lipopeptides
b. LPS
c. Bacterial flagellin
d. CpG DNA
c
TLR6 recognizes?
a. Bacterial lipopeptides
b. LPS
c. CpG DNA
d. Bacterial flagellin
a
TLR7 recognizes?
a. dsRNA
b. Bacterial flagellin
c. ssRNA
d. CpG DNA
c
TLR8 recognizes?
a. dsRNA
b. Bacterial lipopeptides
c. CpG DNA
d. ssRNA
d
TLR9 recognizes?
a. CpG DNA
b. LPS
c. Bacterial peptidoglycan
d. dsRNA
a
