Module 3 - The Body Flashcards
(31 cards)
What are the 5 cardinal signs of inflammation?
Heat, pain, swelling, redness, loss of function
What are cytokines?
Signalling molecules that orchestrate inflammatory response
What is cytokines storm?
When the cytokines-mediated immune response does not subside normally, uncontrolled inflammation in tissues and key organs
WHat is herd immunity?
AKA population immunity, when enough people in the population are immunised to disrupt the chain of spread to protect non-immunised individuals
What are the defences against infectious agents?
External barriers (ie skin)
1st line defence - Proteins (complement, cytokines) & Cells (Neutrophil, basophils, eosinophil, macrophage)
2nd line defence - Proteins (antibodies, cytokines) & Cells (lymphocytes -B & T Cells)
Memory - B & T Cells
What are adaptive defences?
B &T cells. Activated after innate response
What major class of immune cell mediates innate immune response?
Phagocytes
Broad overview of innate & adaptive immunity?
Pathogen eaten by phagocyte, phagocyte presents antigen to lymphocytes, triggers antibody (immunoglobulin) production which binds to pathogen & mark it for destruction
What is humoral vs cell mediated?
Cell mediated involves action of immune cells (ie macrophages, T cells)
Humoral is mediated by extracellular molecules (ie complement proteins, antibodies)
What is innate immunity
Natural/native/non specific
Phagocytes, complement system, cytokines
Low diversity, no memory, quick
What is adaptive immunity
Learned/specific
Lymphocytes, antigens
High diversity, memory, slower
What is haematopoeisis>
Generation of WBCs
Haematopoeitic stem cell - can become myeloid or lymphoid precursor
What is the most abundant leukocyte?
Neutrophil - 40-75%
What are granulocytes?
Named according to ability to react with acid or base dyes.
Neutrophils - antibacterial immunity
Eosinophils - anti parasite immunity
Basophils - important in allergic reactions
What are neutrophils and major function?
Leukocyte.
Spend 12 hrs in blood stream, life span of a few days
Major function - phagocytosis (capture & destroy foreign material)
Respiratory burst is important antibacterial defence
What are eosinophils and major function?
Half life circulation = 30min
12 days in tissues
Phagocytosis similar to neutrophil but more suited to destruction of large parasites/fungal
What are basophils and major function?
Less common than neutrophil/eosinophil.
Contain histamine & serotonin
Functions less well known
Involved in hypersensitivity & allergy
What are dendritic cells?
DCs
Come from myeloid progenitors
Antigen presenting cells - they pick up antigen and display it so T cells can recognise it
What are monocytes?
Monocytes when in blood, called macrophage when in tissue. Live longer than neutrophils
Functions: Antigen presentation Phagocytosis of bacteria Secretion Tumour cell destruction Wound healing
What cytokines to macrophages secrete?
IL-1β
TNF-α
IL-6
CXCL8
IL-12
What are primary lymphoid organs?
Organs where lymphocytes develop and mature:
Bone Marrow
Thymus
Bursa of Fabricious
What are secondary lymphoid organs?
Where baby lymphocytes encounter antigens and are stimulated to become effector and memory cells:
Spleen - antigens that enter blood
Lymph Nodes - antigens from skin & interstitial tissue
MALT - antigens that enter mucosa
What is an antigen?
Any substance that may be specifically bound by an antibody or T cell receptor
What are major factors that determine antigenicity?
Size
Complexity
“Foreignness”
Route of administration
Dose
