Chronic inflammatio Flashcards
acute inflammation is a ……..-mediated immune response
neutrophil
Resolution of acute inflammation (outcomes) requires
- mild injury
- short-lived
- Limit ECM damage
- Capacity for cellular regeneration (limited)
Some outcomes of acute inflammation
- Resolution
- Fibrosis
- chronic inflammation
Define chronic inflammation
Prolonged duration (weeks/months) in which attempts at inflammation, tissue injury and repair co-exist!
What type of immunity is involved in chronic inflammation
Adaptive immunity - in response to continuous injury and a non-neutrophilic response
Microscopic features of chronic inflammation
1- Non-neutrophilic inflammation - macrophages Lymphocytes, plasma cells
- Architectural destruction
- Tissue fibrosis
How long until macrophages are mobilized?
2 days -
TNF-a and IL-1 are secreted by activated macrophages and they
Activate NEUTROPHILS
Which subpopulation of macrophages is important in chronic inflammation?
M2 macrophage! stimulated by iL-13 and IL-4
Antigen presentation to T-cells is mediated by which cytokines?
IL-12
TNF and IL-17 result in
recruitment of neutrophils and macrophages
Causes of chronic inflammation
- Persistent injurious stimulus - HIGH IFN-gamma levels leadin to Granulomatous inflammation (Type 4 Hypers)
- Immune-mediated (autoimmune)
What is a granuloma?
A collection of epithelioid macrophages surrounded by chronic inflammation and fibrosis
The type of necrosis that results from a tuberculous granuloma is
Caseuous type
What is an immune granuloma?
Poorly degradable antigen causes cell-mediated response via IL-2 and IFN-gamma (langerhans type giant cell)
What is a foreign body granuloma?
Inert material too large to preclude by phagocytosis (results in foreign body type giant cell)
- weaker response
In chronic inflammation, persistent foreign and self-antigens can result in
Development of a plasma cell from activated B cells
Form Tertiary lymphoid organs
Immune-mediated reactions in chronic inflammation include
- Autoimmunity
- Excessive and inappropriate immune system activation
- Response to self, and is self-perpetuating
- Immune dysregulation
- IBD
- Hypersensitivity Reactions 1-4
Asthma is an example of what type of hypersensitivity reaction?
Type 1 can lead to - Collagen deposition - fibrosis of BM - Narrowed airways - Chronic obstructive disease
Steroids in asthmatics block
The late phase reaction - avoid eosinophils and lymphocytes
