Inflammation Flashcards
What is inflammation?
A non-specific immune response to cellular injury designed to remove the cause & consequences of injury
What are the conical features of inflammation?
Redness (Rubor) Heat (Calor) Swelling (Tumor) Pain (Dolor) Loss of function (Functio laesa)
What are the causes of inflammation?
Pathogens, allergens, autoantigens, physical damage, extreme temperatures, non-apoptotic cell death
What is acute inflammation?
Short term rapid response non-specific to cellular injury
Instantaneous changes to blood flow
recruitment of immune cells
What occurs to vasculature during acute inflammation?
Structural alterations to the microvasculature
Transient vasoconstriction of arterioles following vasodilation of arterioles and capillaries
Results in increased blood flow to the tissue, presenting rubor and callor
What cells are resident in the interstitium?
Resident macrophages, dendritic cells, mast cells
Where is the interstitium located?
The intermediate layer between the epithelium and the vascular endothelium
What generates inflammatory signals?
Non-apoptotic cell death (Damage-associated molecular patterns)
Pathogen-associated molecular patterns - lipopolysaccharides
Vasodilator release
Name the two main vasodilators:
Nitric oxide and histamine
How are vasodilators released from mast cells?
Mast cell degranulation
What is mast-cell degranulation?
The fusion of lysosomes and secretory vesicles to exocytose compounds
What effect does increased blood flow have in the local area of inflammation?
Locally raised temperature reduces the effectiveness of pathogen reproduction
What effect does histamine exert?
Increased permeability of vascular endothelium, resulting in an exudate forming within tissues,
Cells in walls withdraw from each other (diapedesis), leaky capillaries, the formation of tissue fluid
What is exudate?
Protein-rich fluid
What does exudation and increased blood flow result?
Stasis of circulation in area
Which cells release histamine?
Mast cells, basophils and platelets
What are the benefits of increased vascular permeability?
Increased antibody and leukocyte presence, increased availability of protein and formation of the barrier.
What is the cytokine network?
Interaction between macrophages and CD4 t cells
What inflammatory factor is released from macrophages?
Interleukin-1
GM-CSF
What is the function of IL-1?
Generates chemotactic signal of chemokines, activates T-cells
What is the role performed by IL-12?
Activates Th1, and NK cells
How is chemotaxis achieved?
Chemokines diffuse out to establish a chemical gradient, leukocytes expressing complimentary chemokine receptors migrate towards to chemokine source
What is CXCL8?
IL-8
Which cell secrete CXCL8?
Macrophages
What is the role of CXCL8?
Chemotactic attract for neutrophils , neutrophil migration to the site of infection
What receptors do CXCL8 bind to?
G-coupled 7-TM proteins (CXCR-1/2)
Which cells are the initial responders to inflammation?
Neutrophils