Immunity Flashcards
How do epithelial cells block the entry of microorganisms?
selectively permeable barrier, natural antibiotics, produce cytokines and chemokines to attract immune cells, produce mucins and transport antibodies
Where do chemokines and cytokines diffuse into from the epithelial cells?
lamina propria and blood
Why does opsonisation occur?
So bacteria are easier to phagocytose
What 2 things are extravasated at the site of infection?
antibodies and complement
What are the 5 signs of inflammation?
heat, swelling, redness, pain, loss of function
What are the features of innate immunity?
inbuilt/natural/native, present from birth, not specific, not enhanced by second exposure, no memory, cellular and humoral components
What are the features of adaptive immunity?
acquired, learnt by experience, pathogen-specific, enhanced by second exposure, has memory, cellular and humoral components
What do antibodies tell us?
Which infections an individual has been exposed to
The adaptive system is only present in which group of animals?
Vertebrates
How many classes of antibodies are there and what are they?
5 classes
IgG, IgA, IgM, IgE, IgD
What is the role of macrophages?
phagocytosis and presentation of antigens to T lymphocytes
What are macrophages called before they enter the tissue?
Monocytes
Which blood cell type is anti-parasitic?
Eosinophils
Which cells are involved in the innate response?
macrophages, neutrophils, eosinophils, basophils, mast cells and natural killer cells
Which cells have a 5 lobed nucleus?
Neutrophils
What is the most plentiful WBC?
Neutrophils
What is the smallest WBC?
Lymphocyte
In which cell may the nucleus be obscured and why?
Basophils
They have so many granules within them.
Do neutrophils have receptors?
Yes
for many bacterial constituents
What kind of conditions are neutrophils specialised for and why?
Anaerobic conditions
Because they are required in damaged tissue which is often anaerobic due to lack of blood supply.
What is the first response to inflammation?
Neutrophil arrival
What makes up pus and why?
Dead neutrophils
They are unable to synthesise more granules once activated. Therefore once they have used up all their granules, they die.
What happens when pathogens are too big to digest?
Phagocytes release their lysosomal contents onto the pathogens’ surface.
What do macrophages phagocytose?
microbial cells and damaged or unwanted cells
