2. Innate Immunity II Flashcards
(13 cards)
What do Toll-like Receptors (TLR) trigger?
An intracellular signalling cascade
TLRs play a crucial role in the immune response by initiating signaling pathways that lead to various immune functions.
What can TLRs activate that leads to the transcription of specific proteins?
Adapter proteins
These proteins are essential for conveying signals from TLRs to the nucleus for gene expression.
What is the result of TLR activation on macrophages?
Oxidative burst, inflammation, and production of antiviral genes
This process enhances the macrophages’ ability to eliminate pathogens.
What happens when TLRs are activated in dendritic cells?
Maturation, antigen presentation, and cytokine production
This process is important for bridging innate and adaptive immunity.
Name one function of Natural Killer cells.
Immune surveillance of cancer and viral infected cells
Natural Killer cells play a key role in the innate immune response.
What is the role of dendritic cells in the immune response?
Antigen presentation and cytokine production
Dendritic cells are pivotal in activating T cells and initiating adaptive immunity.
What are the primary functions of macrophages?
Phagocytosis and cytokine production
Macrophages are essential for engulfing pathogens and signaling other immune cells.
What do neutrophils primarily do?
Phagocytosis and enzyme production
Neutrophils are often the first responders to sites of infection.
What are cytokines?
Mediators that can act locally or systemically if released into the blood
Cytokines are critical for cell signaling in the immune system.
What local effects do cytokines have?
- Increase TLR signaling
- Signal cell death
- Increase expression of adhesion molecules
- Increase permeability
- Lower flow rate
- Increase chemokine expression in endothelial cells
These effects help recruit immune cells to the site of infection or injury.
How do cytokines act systemically?
- Recruit white blood cells for long-lasting immunity
- Promote acute phase proteins in the liver
- Signal the hypothalamus to increase body temperature (fever)
- Mobilize cells from the bone marrow to support immune response
Systemic actions of cytokines are vital for coordinating an effective immune response.
What does cytokine signaling cause in terms of receptor activity?
Dimerization of cytokine receptor
This process is crucial for activating intracellular signaling pathways.
What happens after Jak kinase phosphorylates the tyrosine residue?
STAT proteins bind to each docking station and dimerize
Dimerized STAT proteins then promote gene transcription, leading to immune responses.
