Introduction to Clinical Sciences Flashcards
(35 cards)
What is Inflammation?
A reaction to injury or infection involving neutrophils and macrophages
Describe acute infection
Sudden, short duration, usually resolves, neutrophil polymorphs
what is the lifespan of neutrophil polymorphs?
short lived - 3-5 days
Describe the actions of neutrophils
They move to areas of damage via chemotaxis and phagocytose pathogens by releasing enzymes
Describe chronic inflammation
Slow onset, long duration, may never resolve, macrophages
what is the life span of macrophages?
long lived
Where do all immune cells originate
Bone marrow
Where do T cells mature?
Thymus (T cells that recognise self are killed in the thymus)
Where are RBC removed?
The spleen
What is the innate immune response?
Non-specific defence system. Fast onset and short duration e.g mucus or inflammation. Doesn’t depend on lymphocytes. Physical and chemical barriers
what is the adaptive immune response?
Specific (acquired/learned) defence system to destroy/prevent the growth of pathogens. Requires lymphocytes. Slow onset and long duration. Has memory e.g antibodies
What is a neutrophil?
Most abundant WBC, phagocytic and mainly involved in inflammation
What leukocytes are polymorphonuclear?
neutrophils, eosinophils, basophils
what leukocytes are mononuclear leukocytes?
Monocytes, T-cells and B-cells
What are macrophages?
when monocytes migrate from blood to tissue, they become macrophages. They phagocytose, present antigens and secrete cytokines
What are basophils?
Multinucleate cells involved in allergic reactions, eczema, hay fever
What are eosinophils?
multinucleate cells involved in parasitic infections
What do mast cells do?
They are involved in anaphylaxis and asthma. IgE receptors binds to allergens , which then binds to mast cells, causing them to release histamines which causes the response
What do Natural Killer cells do?
They release lytic granules that kill virus infected cells
What is a Complement (C’)?
Group of serum proteins that are secreted by the liver and need to be activated to be functional
What is the action of C’?
Direct lysis
Attract more leukocytes to the cite of infection (chemotaxis)
Coat invading organisms (opsonisation)
What are the main antigen presenting cells?
Dendritic cells
what are cytokines?
soluble mediators secreted by lymphocytes or by monocytes. They act as stimulatory or inhibitory signals between cells
What are interferons?
Interferons are a type of cytokine that induce a state of anti-viral resistance in uninfected cells
