Foundations of immunology Flashcards
What are the two sections of the immune system?
Innate
Adaptive
How does self-tolerance work?
Cells/tissues have a molecule(s) attached that identify them as ‘self’
So immune system does not attack
What are the 2 physical barriers to infection?
Skin
Mucosal barrier
If a pathogen penetrates the body, what section of the immune system is it first to encounter?
Innate
What are the different types of phagocytes
Neutrophils Macrophages Monocytes (differentiate into macrophages) Mast cells Dendritic cells
The innate immune system causes the area around a cut to swell.
How?
Influx of macrophages
Release chemicals to restrict blood-flow away from area
Attack pathogens at site of penetration
Describe the process of phagocytosis (with a macrophage).
Microbe ingested by phagocyte
Phagosome formed
Lysosome fuses with phagosome
Enzymes in lysosome digest pathogen
Antigen from pathogen attached to MHC2 and presented on membrane
Residual waste discharged from phagocyte via exocytosis
Where are all cells involved with the immune system made?
Bone marrow
What is the fancy name for making these new cells?
Hematopoiesis
The stem cell used to manufacture all these immune badbois splits into the common myeloid progenitor, and the common lymphoid progenitor.
Which of these develops to form B cells, T cells and natural killer cells?
Lymphoid progenitor
Monocytes differentiate/divide to form what?
Macrophages
They do so in tissue
Where are macrophages found?
Tissues
Macrophages release cytokines when they encounter a cut/splinter/whatever. Why do they do this, and what is the process called?
Alert other cells to danger
Induce others to site of injury
‘Recruitment’
What is the most abundant type of White blood cell?
Neutrophils
Both neutrophils and macrophages are phagocytes, and will ‘eat’ pathogens when encountered.
What makes macrophages and neutrophils different?
Macrophages present antigens of pathogen
Neutrophils are not APCs
What white blood cells are involved with allergies and asthma?
Mast cells
Eosinophils
Eosinophils contain granules.
What do these granules contain?
Enzymes
Release to destroy infections n shit
Large scale mast cell degranulation is responsible for what medical emergency?
Anaphylactic shock
Basophils are the least common type of what?
Type of WBC
Granulocytes
What 2 places are natural killer cells found?
Blood
Spleen
How do natural killer cells kill pathogens?
Secrete perforin ∴ bore hole in pathogen
Release granzymes that enters pathogen and induces apoptosis
True or false
Natural killer cells are a type of granulocyte.
False
Although they contain granules, they are not
They are a type of lymphocyte
Compliment proteins have 3 pathways of activation. What are they?
Classical
Alternative
Lectin
Where are the compliment proteins mainly synthesised?
Liver
In the classical activation pathway for compliment, what causes C1 to become activated?
Antigen-antibody complex formation
C1 binds to Fc region on antibody
The end product of the classical pathway is when C5b interacts with C6, C7, C8 and C9. What is the end product of this, and what is it’s function?
C5b6789
Membrane attack complex
How is the alternative and lectin activation pathway the same as the classical pathway?
End product is always membrane attack complex
What are the 3 main functions that compliment carries out after activation?
Stimulate inflammation
Induce lysis of microbes (MAC)
Opsonization - cover the pathogen and make it easier for phagocytes to engulf
Cytokines are chemicals used by immune cells, to communicate with each other.
There are 3 ways that cytokines work, to do with where they go and what cells they activate. Name these, and briefly describe which one is which.
Autocrine - binds to receptor on the same cell
Paracrine - binds to nearby cell
Endocrine - cytokines go into circulation then bind to distant cell
Inflammatory response is categorised into 2 types. What are they?
Acute - initial response to harmful stimuli
Chronic - progressive sift in types of cells at site of inflammation. Simultaneous destruction and healing of tissue.
What is the innate immune response?
Non-specific, first immune response
What is the difference between the classical pathway and lectin pathway?
The lectin pathway starts with mannose-binding lectin (MBL) or ficolin binding to certain sugars
Classical pathway starts with C1 binding to an antibody in a antibody-antigen complex
How does the alternative compliment pathway start?
The pathway is triggered when the C3b protein directly binds a microbe
