Exam 1: Chapters 2 and 3 Flashcards
What is septic shock?
Cardiovascular collapse due to a body-wide increase in vascular permeability
Fill in the blanks.
- Phosphocholine; 2. C-reactive protein (CRP); 3. C1 complex; 4. C4; 5. C4a; 6. C4b; 7. C2; 8. C2b; 9. C2a; 10. C3; 11. C2aC4b; 12. C3a; 13. C3b
What are the functions of protease inhibitors in the innate response?
Protease inhibitors trick proteases into cleaving their covalent bonds rather than those of C3b on the pathogen surface, thus activating the protease inhibitor to enclose the protease and prevent it from deactivating complement
What are the three responses to infection?
Immediate Innate Response, Mobilized Innate Response, Adaptive Response
What mechanism(s) protect human cells from complement?
Factor H and Factor I; MCP and DAF
What are the three ways that complement can be activated?
Alternative pathway, classical pathway, lectin pathway
Fill in the blanks.
- C3; 2. iC3; 3. Factor B; 4. Factor D; 5. iC3Bb; 6. Bb; 7. Ba; 8. C3; 9. C3a; 10. C3b; 11. C3b; 12. Factor B; 13. Factor D; 14. C3bBb; 15. C3; 16. C3a; 17. C3b
What are defensins and how do they work?
Defensins are amphipathic proteins that insert themselves into pathogen membranes, which disrupts membrane integrity by forming a pore
How are INF-B (Interferon Beta) and INF-a (Interferon Alpha) activated?
RLR binds to viral RNA, activating IRF-3, which produces IFN-B. An autocrine signal initiated by IFN-B activates IRF-7, which produces IFN-a. A paracrine signal by IFN-B warns other cells.
How does complement fight infection?
Coats pathogens and makes them easier to identify and phagocytose; pokes holes through pathogen membranes
How does interferon affect NK cells?
Interferon recruits NK cells to sites of infection and increases their killing ability
How are complement coated pathogens recognized?
Complement receptors (CR1, CR2, CR3, CR4) on the surface of the macrophages
What are chemokines and how do they work?
Chemokines are a specific type of cytokine that recruit cells via a chemokine gradient; neutrophils, NK cells, etc. follow the gradient to find the greatest amount of infection
What are the three functions of the immediate innate immune system?
Identify pathogen, induce inflammation, kill pathogen/prevent pathogen from causing damage
Are the receptors on macrophages pathogen specific?
No, they recognize broad classes of pathogens
Fill in the blanks.
- Mannose Binding Lectin (MBL); 2. Mannose; 3. C4; 4. C4a; 5. C4b; 6. C2; 7. C2b; 8. C2a; 9. C2aC4b; 10. C3; 11. C3a; 12. C3b
How are pathogens opsonized with complement destroyed?
Macrophages and neutrophils recognize opsonized pathogens and phagocytose them
What other serum proteins function in the innate immune response?
Proteins of the coagulation cascade and proteins of the kinin system
What is the consequence of interferon signaling?
The anti-viral state will activate, which prevents viral replication, alerts other cells that they are infected, and improves the adaptive immune response
How do Nod-Like Receptors (NLRs) recognize pathogens and send a signal?
NLRs function similar to TLRS, except they bind to bacterial components within the cytoplasm
How does the complement system induce inflammation?
The C3a and C5a fragments (anaphalatoxins) induce an inflammatory response by inducing vascular permeability and acting as a chemoattractant for neutrophils and macrophages
How does the barrier function work?
A combination of mechanical, microbial, and chemical defenses in the skin, gut, lungs, and eyes/nose/mouth
What is the role of platelets in innate immunity?
Platelets release inflammatory mediators
How do neutrophils kill pathogens?
Respiratory burst, low pH, defensins, anti-microbial peptides, withholding nutrients from pathogens
