Inflammation 2 Flashcards
Cells of inflammation
Granulocytes
-Neutrophils
-Eosinophils
-Basophils
Mononuclear cells
-Monocytes/Macrophages
-Lymphocytes/plasma cells
-Mast cells
Neutrophils morphology
-Segmented multilobed nucleus
-Cytoplasmic granules
Primary granules
Secondary
Neutral non staining granules
Important primary granules neutrophils
Myeloperoxidase and lysozyme
Important secondary granules neutrophils
Collagenase
Neutrophil characteristics
-Highly differentiated and no longer divide
-Mainly anaerobic and have abundant glycogen
-Function in low oxygen
-Metabolize large amounts of oxygen in response to activation
Neutrophils action
Produced in bone marrow and remain for a day in storage pool. Enter the blood and circulate for 5-12 hrs. Once they emigrate they live for 1-4 days in tissues. Apoptosis following withdrawal of growth factors and other stimuli
Neutrophil inflammatory function
-Phagocytosis and killing
Oxygen independent and dependent
NO also present
-Secrete inflammatory products (cytokines, arachidonic products, NETs, defensins)
NETs
Web like matrix of DNA/ proteins and neutrophil granule products that trap and kill pathogen
-May be involved in autoimmunity and thrombosis
Eosinophils morphology
-Segmented bilobed nucleus
-Four type of cytoplasmic granules
Important eosinophil granules
Major basic protein and histaminase
Eosinophil characteristics
Not as well understood
-Allergic reactions or parasitic infections
-Associated with mast cells
Eosinophil kinetics
30min half-life in blood with a 12-day half-life in tissue
Inflammatory function of eosinophils
-Secrete lysosomal enzymes (damage microbe membranes and degrade certain pro-inflammatory products like histamine)
-Secrete mediators (cytokines, chemokines, arachidonic acid metabolites)
Basophil morphology
-Multilobed nucleus
-Cytoplasmic granules that obscure the nucleus morphology
Basophil granules
-Histamine
-Proteoglycans
-Proteases
Basophil characteristics
Associated with IgE dependent allergic reactions or parasitic infections
-Poorly phagocytic and sluggishly motile
Basophil kinets
Probably similar to neutrophils
Basophil inflammatory functions
-Secrete lysosomal enzymes
-Secrete other mediators
Mast cell morphology
Smaller
-Oval to round nucleus
-Metachromatic cytoplasmic granules
Mast cell types
-Connective tissues
-Mucosal
Characteristics of mast cells
Prominent at allergic reactions or parasitic infections
Kinetics of mast cells
4–12-week lifespan
Major inflammatory functions of mast cells
-Bronchoconstriction, vasodilation and ECM degradation
-Secrete mediators
Monocyte vs macrophage
Monocyte in the blood macrophage in the tissue
Characteristics of monocytes
Source of macrophages and dendritic cells
Kinetics of monocytes
Circulate in blood for 1-3 days and slower to emigrate than neutrophils
Fixed macrophages
-Derived from monocytes
-Emigrate in response to cytokines can replicate locally witing the tissues to maintain the fixed population
-Exist in areas where microbial invasion is most likely
-Can be innate or acquired immunity
Dendritic cells
Process and present antigen to T lymphocytes (MHC II class molecules)
Kinetics of dendritic cells
Derived from monocyte and emigrate in response to stimuli
Macrophage morphology
Round to oval and slightly indented nucleus
Cytoplasmic granules
Abundant organelles
Characteristics of macrophages
-Multifunctional
-Aerobic
-Important for inflammation and immunologic events
-Critical for chronic inflammation and healing
Types of macrophages
M1-Pro-inflammatory, host defense and anti-tumor immunity
M2- Regulate healing, anti-inflammatory, suppress host defenses
Inflammatory function of macrophages
-Phagocytosis (after neutrophils, but better at it)
-Chronic inflammation
-Innate and acquired immunity
-Lysosomal enzymes
-Oxygen metabolites
-Complement components
-Coagulation factors
NK cells
Cytotoxic innate immunity
-Respond to altered MHC 1 molecules or stress associated proteins
-Lysis of target cells with perforins and granzyme
-Early responder to virus-infected or tumor cells
T cells
Either CD4 or CD8 cytotoxic
B cells
Humoral immunity
Defined by immunoglobin
Differentiate into antibody-producing plasma cells following stimulation
