Inflammation-Mesa Flashcards
What cells are most involved in acute inflammation?
Neutrophils
What is exudate?
- Leakage of proteinaceous fluid
* High specific gravity
What is transudate?
- Acellular leakage of fluid close to water
* Low specific gravity
Extravasation of PMNs
- Margination - neutrophils go toward walls
- Rolling - tumbling and heaping
- Adhesion
- Transmigration - leukocytes leaving circulatory system
What is a PMN?
A fancy ass Neutrophil
What are secretins?
Adhesion molecules from endothelial cells
What are integrins?
Adhesion molecules from many different cell types
What is chemotaxis?
- PMNs go to site of injury after transmigration
* Regulated by chemokines
What is leukocyte activation make PMNs do?
• Produce eicosanoids such as:
- Prostaglandin
- Leukotrines
- Lipoxins
What are the 9 steps of inflammation?
- Vasodilation
- Increased vascular permeability
- Leakage of exudate
- Margination, rolling, adhesion
- Transmigration
- Chemotaxis
- PMN activation
- Phagocytosis
- Termination
Histamine
- Main mediator of inflammation
- IgE on mast cell triggers release
- Made in mast cells, basophils, platelets
- Causes: vasodilation, increased vascular permeability and endothelial activation
Serotonin
- Made in platelets
- Evokes NO synthase which generates NO (vasodilator)
- Causes: vasodilation and increased vascular permeability
Complement
• Final product results in lysis of membrane of bacteria
Kinin System
• Bradykinin is main component
- Causes increased permeability but results in smooth muscle contraction (painful!)
Clotting factors
- Production of fibrin (coagulation)
* Fibrinolysis - dissolves the fibrin
Prostaglandins
- Made in mast cells and leukocytes
- Actions: pain, fever and clotting
- Aspirin counteracts these
Leukotrienes
- Made in mast cells
* Causes: increased vascular permeability, chemotaxis, leukocyte adhesion and activation
Lipoxins
- Inhibit chemotaxis and cause vasodilation
* Counteract leukotrienes
Platelet-Activating Factor (PAF)
- Made in leukocytes and mast cells
* Causes: vasodilation, increased vascular permeability, leukocyte adhesion, chemotaxis, degranulation, oxidative burst
Cytokines/Chemokines
Cytokines • Proteins produced by many cells • Usually lymphocytes and macrophages Chemokines • Small proteins which are attractants for PMNs
What are the 2 most powerful regulating cytokines and what produces them?
TNF-α and IL-2; Macrophages
Nitric Oxide (NO)
- Potent vasodilator
* Produced from asinine by NO synthase
Lysosomal constituents - Primary granules
• Azurophilic (non-specific) • Main components: - Myeloperoxidase - Lysozyme - Acid hydrolyses
Lysosomal constituents - Secondary granules
• Specific (more mature) • Main components: - Lactoferrin - Lysozyme - Alkaline - Phosphatase - Collagenase
Free radicals
• Produced by cells in the inflammatory process
- Very toxic to microbes
Neuropeptides
- Produced in CNS
* Not a big role in acute inflammatory process
What is Substance P used for?
Mood disorders
What is Neurokinin A?
Acts like neurotransmitters
What are the 3 possibly outcomes of acute inflammation?
- Hopefully 100% resolution
- Sometimes scarring
- Chronic inflammation
What are the morphological patterns of acute inflammation?
- Serous (watery)
- Fibrinous (hemorrhagic, rich in fibrin)
- Suppurative (pus(sy))
- Ulcerative
What are some causes of chronic inflammation?
- Persistence of infection
- Prolonged exposure to insult
- Auto-immunity
Cellular players of chronic inflammation
- Lymphocytes
- Macrophages
- Plasma cells
- Eosinophils
- Mast cells
What is a granuloma?
A focus of chronic inflammation consisting of a microscopic aggregation of macrophages that are transformed into epithelial-like cells
What are the 4 components of a granuloma?
- Fibroblasts along the outside
- Lymphs
- Histiocytes
- Giant cells (macrophages that fuse together)
If there is caseating necrosis in a granuloma what does that mean?
Tuberculosis!
What are some clinical manifestations of chronic inflammation?
- Fevers, chills
- C-Reactive Protein (CRP)
- Acute phase reactants (α1-α2)
- Erythrocyte sedimentation rate (ESR) increases
- Leukocytes
- Increase production of various cytokines
Serum protein electrophoresis
- Albumin is the largest peak
* α1 and α2 are elevated in acute inflammation
What are the consequences of defective inflammation?
- Results in increased susceptibility to infections
* Associated with delayed wound healing
What are the consequences of excessive inflammation?
- The basis for many types of disease
- May cause unregulated immune response (allergies) or auto-immune disorders
- Plays a role in arteriosclerosis, ischemic heart disease and some neurodegenerative diseases
