Exam 3: Inflammation and Repair Flashcards
What are the acute inflammation effector cells?
Vascular endothelial cells Neutrophils Mast cells and basophils Eosinophils Monocytes and macrophages
What role do vascular endothelial cells play in inflammation?
Contraction
Release of chemical mediators
Expression of adhesion molecules and receptors
What are cell characteristics of neutrophils?
Segmented nucleus
Multiple complex granules
What is the main recruiter or neutrophils?
IL-8
How long do neutrophils live?
24 hours in the circulation
1-2 days in tissue
What is the function of neutrophils?
Innate immunity to bacteria and fungi
Phagocytosis
Release of granular contents
What are the 3 phases of phagocytosis?
Attachment of particles to the cell surface
Ingestion of particles
Breakdown of particles
What facilitates phagocytosis?
Opsonization
What are the granules in a neutrophil?
Myeloperoxidase
Lysozyme
What does myeloperoxidase to?
Converts hydrogen peroxide to hypochlorous acid, which is toxic to microbes
Why can brids not liquefy the exudate?
Reptiles and birds have reduced concentrations of certain enzymes
What are neutrophil extracellular traps (NETs)?
Extracellular fibrillary networks that provide a high concentration of antimicrobial substances
What are NETs composed of?
A meshwork of nuclear chromatin that binds and concentrates antimicrobial peptides and enzyems
Where does the production and maturation of neutrophils take place?
Bone marrow
What percentage of WBCs are eosinophils?
1-5%
How long do eosinophils live?
12 hours in the circulation
1 week in tissue
When do eosinophils enter lesions?
During the transition from acute to more chronic inflammation
What are eosinophils attracted by?
Histamine
Eosinophil chemoattractant factor A
What are the functions of eosinophis?
Innate immunity to parasires
Associated with allergic disease or hypersensitivity reactions
Modulate local immune responses
What are the cell characteristics of eosinophils?
Bilobed nucleus
Cytoplasmic granules
What are the granules of eosinophils?
Lysosomal enzymes and perioxidases
Where are mast cells/basophils found?
In all supporting tissues
How long do mast cells/basophils live?
4-12 weeks
What are the metachromatic granules of mast cells/basophils
Histamine
Eosinophil chemotactic factor
Synthesize prostaglandins, leukotrienes, and PAF
What do mast cells express high affinity for?
Receptors for IgE
Describe the process of monocytes becoming macrophages
Monocytes originate in bone marrow, migrate in blood, then settle in tissues/take up residence as tissue macrophages
What is the life span of monocytes/macrophages?
Short lived in circulation (monocyte)
Long lived in tissues (macrophage)
What are the functions of monocytes/macrophages?
Phagocytosis
Antigen presentation
Immune modulation
What are the cell characteristics of monocytes?
Large nucleus, with indentation
Multiple granules and vacuoles
What are the 2 types of macrophages?
Those that reside within a specific tissue and those derive from monocytes in response to a stimulus
What are the tissue macrophages?
Kupffer cells (liver) Microglia (CNS) Alveolar macrophages (lung) Langerhans cells (skin) Osteoclasts (bone)
How do macrophages recruited to inflammation respond by?
Chemotaxis
When do macrophages arrive to an area of inflammation?
12-48 hours after neutrophils as a second wave
What do macrophages secrete to modulate the immune response?
Cytokines
What do platelets look like?
Biconvex discs
What do platelets arise from?
Megakaryocte fragmentation in marrow
What is the function of platelets?
Hemostastis control
Deliver inflammatory mediators to injured sites
What is a preformed substance in the granules of paltelets?
Histamine
What is catarrhal inflammation?
Secretion of large amounts of mucus
What is seen grossly with catarrhal inflammation?
Clear film
What is seen microscopically with catarrhal inflammation?
Pale blue strands of mucus, may be mixed with inflammatory cells
May have an increase number of goblet cells
What is pseudomembranous?
A covering of a mucosal surface by a coagulum of fibrin, mucus, necrotic cells, and leukocytes
Same thing as necrotizing
