Cells of the Immune System Flashcards
(52 cards)
What are the 3 types of granulocytes
Neutrophils
Eosionphils
Basophils
What are there most common form of granulocyte
Neutrophils
How do neutrophils come into contact with and destroy bacteria etc.
They circulate in the bloodstream and can phagocytose bacteria and dat
What do eosinophils do
They are important for defence against parasites and are also involved in allergic reactions
What do basophils do
Important against parasites and are involved in allergic reactions
What is the difference between eosinophils and basophils
Eosinophils - eosin stain used on them
Basophils - Basic dye used to stain them
What do mast cells do
Important against parasites and bind to IgE that leads to crossing linking between the IgE receptors and an antigen that leads to calcium influx, degranulation and histamine release in an allergic response
What do monocytes develop into
Macrophages
Where are monocytes found
In the bloodstream and tissues
What do monocytes and macrophages do
They coordinate an immune response by telling other immune cells that there’s a problem.
Macrophages also recycle dead cells like RBCs and clear away cellular debris
What do neutrophils do at the site of local tissue injury
Accumulate at site in minutes and tell other neutrophils to swarm site using lipids and mediators.
Their movement and signals tell macrophages and monocytes to surround the neutrophil cluster and for a tight wound seal
What do dendritic cells develop from
Monocytes
What is the main function of dendritic cells
They are an important antigen presenting cell that process large molecules into readable fragments recognised by B and T cells.
What is an examples of an intracellular antigen
A virus
What kind of immunity are natural killer cells (Innate/adaptive)
Both BITCH
What do natural killer cells do
Recognising and killing virus infected cells or tumour cells
How do natural killer cells kill virus infected cells and tumour cells
They have intracellular compartments called granules that are filled with proteins that can form holes in the target cell and also cause apoptosis
What is the main difference between apoptosis and necrosis
Apoptosis doesn’t release danger signals that can lead to greater immune activation and inflammation
What are the functions of B cells
They present antigens to T cells and produce antibodies to neutralise infectious microbes and the toxins produced by them
What are the major roles of antibodies
- Neutralisation occurs when the pathogen, because it is covered in antibodies, is unable to bind and infect host cells
- In opsonisation an antibody bound pathogen serves as a red flag to alert immune cells like neutrophils and macrophages to engulf and digest the pathogen
- Complement is a process for directly destroying, or lysing, bacteria
What are the 2 ways that antibodies can be expressed
B cell receptors that sit on the surface of a B cell is actually an antibody
B cells also secrete antibodies to diffuse and bind to pathogens
Why is the dual expression of antibodies important
As the bacterium is recognised using the antibodies on the B cell surface and the antibodies that the B cell secretes is the action taken that actually kills the pathogen
What categories can an antibody fall into
IgM IgD IgG IgA IgE
What does Ig stand for in reference to antibodies
Ig = Immunoglobulin = antibody
