Chronic Inflammation 1 Flashcards
Define chronic inflammation.
Inflammation in which the cell population is especially lymphocytes, plasma cells, macrophages. It involves tissue damage (necrosis) and loss of function. It is longer term in comparison with acute inflammation.
How can chronic inflammation arise?
Following ongoing acute inflammation.
Arises as primary pathology.
What are the clinical presentations of chronic inflammation?
Often no specific sore bit.
Malaise and weight loss.
Loss of function.
Describe organisation as an outcome of acute inflammation.
Granulation tissue formation leading to fibrosis and scar formation.
Describe the steps leading to granulation tissue formation.
Capillaries grow into inflammatory mass, access of plasma proteins, macrophages from blood and tissue, fibroblasts lay down collagen to repair damaged tissue, collagen replaces inflammatory exudate.
What is the function of granulation tissue?
Patches tissue defects.
Replaces dead or necrotic tissue.
Contracts and pulls skin together.
What is the products of granulation tissue?
Scar (fibrous tissue).
Give an example of where fibrosis is a problem.
Adhesions between loops of bowl following peritonitis.
What is acne an example of?
Chronic inflammation.
Give more examples of chronic inflammation.
Cholecystitis, peptic ulcers, osteomyelitis.
Give examples of things that cause primary chronic inflammation.
Autoimmune diseases, material resistant to digestion, exogenous substances, endogenous substances.
What is autoimmune disease?
Autoantibodies directed against own cell and tissue components (autoantigens), they destroy tissues/organs/cells and can cause chronic inflammation.
Give examples of materials resistant to digestion that would cause primary chronic inflammation.
Mycobacteria, Brucella, viruses, cell walls resistant to enzymes.
Give examples of exogenous substances that would cause primary chronic inflammation.
Sutures, metal and plastic, e.g. joint replacement, mineral crystals, glass
Give examples of endogenous substances that would cause primary chronic inflammation.
Necrotic tissue, keratin, hair (all not easily phagocytosed).
What is autoimmune thyroiditis?
Chronic disease in which the body interprets the thyroid gland and its hormone products as threats and produces antibodies against them.
What cells are involved in chronic inflammation?
lymphocytes, plasma cells, macrophages, fibroblasts
What tissue components are involved in chronic inflammation?
granulation tissue and collagen
What is the appearance, function and different types of lymphocyte?
Small round cells
T-cells and B-cells
Functions: immune response and memory
What is a plasma cell?
Intermediate sized cell, which is a differentiated B-cell - it is involved with antibody production.
What are the roles of B-cells?
differentiate into plasma cells (to make antibodies)
facilitate immune response
act w/ macrophages (antigen presenting capacity)
immune memory
What are the roles of T-cells?
Production of cytokines and interferons
Damage and lyse other cells and destroy antigen by chemical mechanisms (granule proteins)
What do cytokines do?
attract, hold and activate macrophages and other cells, e.g. lymphocytes
affect permeability of blood vessels
What do interferons do?
Produce antiviral effects and attract and stimulate other cells
What are the role of natural killer cells?
Destroy antigens and cells by granule proteins
What is the role of the macrophage?
removal of debris (phagocytosis)
antigen presenting
produce interferons and other chemicals (destroy and influence process)
Name subsets of macrophages.
Monocytes, histiocyte, activated macrophage, epithelioid cell, giant cell
Where are macrophages made?
In bone marrow like most other blood cells, enter blood as monocytes and when they move into tissues, mature into macrophages.
Macrophages will move in and take over from neutrophils in inflammation, here they can phagocytose pathogens, what enzyme is responsible for digestion of engulfed pathogens?
lysozyme enzymes found in lysosomes which fuse with phagosome to form phagolysosome and digest antigens.
What are the role of fibroblasts?
Motile metabolically active cells which make and assemble structural proteins (collagen).
Where do T-cells mature in the body?
Thymus.
