Cell inflammation Flashcards
What is inflammation?
Non-specific response to cellular injury
Removes the cause and consequence of injury
A universal process occurs in most diseases
What are the 4 main signs of acute inflammation?
Swelling Heat Redness Pain (loss of function)
What causes inflammation?
Pathogens Allergens Auto-antigens Physical damage Extreme temperatures Non-apoptotic cell death
What is acute inflammation?
Rapid repose non-specific response to cellular injury
Applies to any viable, vascularised tissue
What happens during inflammation?
Change in local blood flow
Structural changes in the microvasculature
Recruitment?accumulation of immune cells and proteins
What happens when the tissue is damaged?
Inflammatory signals Vasodilators released -histamine -nitric oxide Vascular changes - increased permeability -dilation -reduced flow -plasma oxide
What benefits does increased vascular permeability and leakage bring?
Increased antibodies
Increased protein
Increased barrier
Increased Leukocyte migration
What is exudate?
Fluid, proteins and cells that have seeped out of a blood vessel
Acts as barrier
What happens during immune cell recruitment?
Chemokines produced diffuse out forming gradient
Leukocytes expressing complementary chemokine receptors migrate towards the chemokine source
What are the 4 steps of neutrophil extravasation?
Chemo-attraction
Rolling adhesion
Tight-adhesion
Transmigration (neurophil swarming)
What do neutrophils do at the site of inflammation?
Pathogen recognition Pathogen Clearance -Phagocytosis - Netosis Cytokine secretion -recruitment and activation of other immune cells
How is acute inflammation resolved?
Pathogen recognition Neutrophils have a short half life Macrophages -clear apoptotic cells -produce anti-inflammatory mediators Mainly self-regualting
Name some diseases characterised by chronicle inflammation?
Arthritis Asthma Hepatitis Multiple Sclerosis Psoriasis
Name some diseases associated with granulomatous inflammation?
TB
Leprosy
Crohn’s disease
What is chronic inflammation?
Similar to acute but there is persistent inflammatory stimuli
e.g infection or toxic stimuli
What does persistent stimuli cause?
Distinct immune cells infiltrate -Macrophages -T cells -Plasma cells A vicious cycle -bystander tissue destruction -concurrent repaint processes
What is the role of macrophages in inflammation?
Recruited as monocytes to the sire of inflammation Phagocytic- clear cellular debris Cytotoxic Anti-inflammatory Wound repair
Why can macrophages cause harm?
Cytotoxic- don’t only kill pathogen but surrounding cells
Inflammatory
Pro-fibrotic- can cause permanent damage to tissue function
What is the role of T-lymphocytes?
Pro-inflammatory- clear infection well
Cytotoxic- don’t damage surrounding tissues
Regulatory
What is the role of B-lymphocytes?
Generate plasma cells that secrete antibodies
Protective- clear infection
Inflammatory- driving reactions against self
Can be local or operate remotely
What is granulomatous inflammation?
Chronic inflammation with distinct pattern of granuloma formation
Trigged by a strong T-cell response
What is the characteristic circular space in granulomatous inflammation?
Aggregation of activated macrophages
A barrier defined for clearance
What are the outcomes of acute inflammation?
Clear inflammatory agents
Remove damaged cells
Restore normal tissue function
What are the outcomes of chronic inflammation?
Excess tissue damage
Scarring
Loss of organ function- organ failure
What does wound healing lead to?
Extra-cellular matriculates deposition
What are the consequences of inflammation?
Broncho-pneumonia
Scarring
Can lead to loss of function in tissues
