Midterm Part 2 Flashcards
What kinds of cells does chronic inflammation involve?
(Years): characterized by the activation of macrophages and T cells
What do TLRs bind to?
PAMPS
(Step 1 of inflammatory response)
- What transcription factor does the TLR/PAMP interaction produce?
- What cytokines are produced as a result of this reaction?
- nF-KB
- IL-1, IL-6, TNFa +CXCL8
What cells initiate the inflammatory response?
- macrophages and mast cells
What is the effect of histamine?
Histamine causes blood vessels to dilate, thus increasing blood flow to the area and resulting in the redness and heat association with inflammation
What is extravasation?
adhesion molecules allow leukocytes such as neutrophils and monocytes to stick to the endothelial cells of the blood vessel and then squeeze through the spaces between the endothelial cells of the blood vessel and into the tissue
What is the function of CXCL8?
guides the neutrophils, monocytes and dendritic cells to location of the bacteria in the tissues.
What do neutrophils do? What makes them good at their job? How many pathogens can they kill?
- phagocytose pathogen
- there are a lot of them
- 1 pathogen
What is the function of monocytes? Why are they good at killing cells?
- to mature into macrophages and then phagocytose
- expert phagocytes, can kill 100s of cells
How do neutrophils and monocytes kill pathogens?
- phagocytosis
- pathogen goes into a phagosome, and is then acidified and membrane-bound granules called lysosomes fuse with the phagosome to form a phagolysosome
What are the 5 steps of the inflammatory response?
- RECOGNITION: PRR/PAMP interaction releases alarm cytokines
- INITIATION: Macrophages and mast cells initiate inflammatory response, cause vasodilation and increased vascularity
- CELLULAR INFILTRATION: Neutrophils and macrophages are recruited and phagocytose
- Clotting and repair
- Pus
Does The innate immune response vary between a first and a second exposure to a pathogen?
No
True or false: within minutes, vasodilation occurs and brings leukocytes to the site of infection
False (within hours)
Where are mast cells found? What is the structure of the cell? What do they do?
- Rare in blood, tissue resident • Small nucleous, granule-rich cytoplasm • Release granule contents (histamine) to trigger reactions
Where are DC’s found? Where do they go when they are activated?
- in tissues
- secondary lymphoid organs
What is a sign of a non-self microorganism?
1. Cell wall components
• LPS, peptidoglycan
2. Flagella
• flagellin
3. Nucleic acids
• Bacterial DNA
• dsRNA in virusesWhat are the two kinds of PRR’s? What are the outcomes of the two kinds of PAMP/PRR interactions?
Phagocytosis receptors and TLRs
- phagocytic: contains the infection
- TLRs: call for help
(Fourth step of inflammatory response) How does the body clot/repair skin?
- coagulation proteins and platelets are recruited
- Macrophages replace the scab
Where does the DC activate the B and T cells?
The lymph nodes
Where does adaptive immunity begin?
The secondary lymph organs
What do B and T cells do in the absence of infection?
Circulate through the lymph nodes looking for pathogens
How is the adaptive immune system initiated?
DC’s phagocytose pathogen in the tissue, and travel to the lymph nodes (tissue infection) or spleen (systemic infection) to activate T cells
Where do DC’s mature?
In the lymph nodes or spleen
What is an antigen?
A protein that is recognized by lymphocytes
Which cells present antigen?
ALL cells can present antigen, but only some cells are professional APCs
What are the three types of professional APCs?
- DC (happens early, can travel)
- Macrophage (happens later, cannot travel)
- B cell (happens later, to efficiently activate more Th cells)
