Complete Solution
Tissue resident sentinel cells include (3 types) Correct Answer: Dendritic cells, macrophages, and mast
cells
Circulating leukocytes involved in innate response (2 types) Correct Answer: Monocytes and neutrophils
Phagocytic immune cells (2 types) Correct Answer: Macrophages and neutrophils
Difference between macrophages and neutrophils? Correct Answer: Neutrophils are short lived and will
undergo apoptosis after eating a microbe; macrophages are longer-lived and will eat apoptotic cells and
waste
General cytokine role in innate immune response (and what cells release them?) Correct Answer:
Released by dendritic cells, macrophages, and mast cells. Pro-inflammatory molecules that interact with
blood vessel endothelium to recruit circulating leukocytes, fluid, and proteins into tissue
Which tissue-resident sentinel cell will release histamine upon activation? Correct Answer: Mast cell
Cytokines promote up-regulation of what kind of molecule within blood vessel walls? Correct Answer:
Adhesion molecules
E-Selectin Correct Answer: An adhesion molecule that helps to slow down circulating leukocytes in
innate immune response (low-affinity interaction)
E-Selectin Ligand Correct Answer: A ligand expressed by circulating leukocytes that helps them stick to
blood vessel endothelium in innate immune response
ICAM-1 Correct Answer: An adhesion molecule that helps circulating leukocytes bind to blood vessel
endothelium in innate immune response (high-affinity interaction)
Integrins (and the name of a specific one) Correct Answer: A class of adhesion molecules expressed on
circulating leukocytes; LFA-1 binds to ICAM-1 in a high affinity interaction during the innate
inflammatory response
Stable Arrest Correct Answer: When a circulating leukocyte comes to a stop within the endothelium
thanks to adhesion molecule interactions and can enter the tissue
Pus Correct Answer: Comprised of fluid and apoptotic cells/waste as a result of an inflammatory
response (DNA, dead bacteria, apoptotic neutrophils)
Psoriasis overview Correct Answer: Autoimmune disease that can cause skin plaques and arthritis; Skin
plaques are caused by immune cells migrating into the skin and initiating an inflammatory response
, Psoriasis risk factors Correct Answer: History of strep infections, skin injury, first degree relative with
psoriasis
TNF-alpha in psoriasis Correct Answer: A pro-inflammatory cytokine expressed in psoriasis that recruits
immune cells into the skin and also acts directly on epithelial cells to produce thickened/raised patches
Psoriasis treatment (biologics) Correct Answer: Target the pro-inflammatory cytokine TNF-alpha and
therefore prevent the expression of adhesion molecules on endothelial cells and prevent TNF-alpha
from acting directly on epithelial cells
Possible side effects of medications that block adhesion molecules Correct Answer: Susceptibility to
infection due to inhibiting leukocyte entry into tissue
Most abundant leukocyte Correct Answer: Neutrophils
What kind of infections are neutrophils particularly effective against? Correct Answer: Extracellular
bacterial infections
Plasmacytoid dendritic cell Correct Answer: A type of sentinel cell that detects viruses and releases type
1 interferons
Type 1 Interferons (Type 1 IFNs) function and the cell that is most efficient at producing them Correct
Answer: Group of cytokines that activate the antiviral state during viral infection; Plasmacytoid dendritic
cells
The Antiviral State Correct Answer: Protective state that cells enter in response to Type I Interferons;
proteins that can bind to viral double-stranded RNA are produced, infected cells will die, RNAse activity
is induced
Pathogen-associated molecular patterns (PAMPs) Correct Answer: Molecules that are commonly
expressed on pathogens but not vertebrate cells, help distinguish self from non-self; can be on cell
surface or released from cells
Gram-Negative Bacterial PAMPs Correct Answer: Lipopolysaccharide (LPS) in cell wall, flagellin
Gram-Positive Bacterial PAMPs Correct Answer: Teichoic acids and peptidoglycan in cell wall, flagellin
Pattern recognition receptors (PRRs) Correct Answer: Receptors that bind to PAMPs and activate an
immune response; important in innate immunity
Toll-like receptors (TLRs) Correct Answer: A group of pattern recognition receptors; can be located on
immune cell surface or within the cell on the endosomal membrane
Viral PAMPs Correct Answer: Nucleic acids
What happens when pattern recognition receptors or toll-like receptors bind to a PAMP? How does this
response differ among different kinds of infection (viral vs. bacterial)? Correct Answer: The immune cell
is activated and will secrete pro-inflammatory cytokines such as type 1 interferons (viral infection),