Immunology Flashcards
What are the components of Innate immunity
barrier factors (skin, mucosa), soluble factors (complement, cytokines, peptides), cell-associated factors (PRRs, cytokines, peptides), cells (granulocytes, monocytes/macrophages, dendritic cells, NK cells)
What are the components of adaptive immunity?
T cells and b cells
What are the two main types of t cells and what do they do?
CD4+ T Cells = helper cells, secrete cytokines to coordinate macrophages and b cells, can only see antigen on MHC II
CD8+ T Cells = cytotoxic cells, kills target cells, specific MHC I molecule
Explain the process of activation of B cells
B cell internalises molecule and binds to T cell. When a mature CD4+ T cell secretes cytokines it transforms B cell into plasma cell that secretes antibodies tagging bacteria for destruction (opsonization)
What do B cells cause when activated
neutralisation (deactives venom etc.), opsonisation (attacked by antibodies so macrophages can reconise), complement activation (drilling hole to kill)
How are dendritic cells involved in the bridging process between adaptive and innate immunity?
immature dendritic cells under epithelium ingest pathogens and move into lymph node and present MHC II protein to T cell
Why does the immune response need to be halted?
Immune response can cause self-damage
Do all adaptive cells die after all the invading pathogens are killed?
No, some stay on as memory cells
Why are there memory cells?
Effective response when infected by same pathogen again
What is sterilising immunity?
when the immune system is so efficient it eliminated before symptoms occur
What are the mechanical barriers of the skin?
epithelial cells, longitudional flow of air or fluid
What are the chemical barriers of the skin?
fatty acids, beta-defensins Laemella bodies, cathelicidin
What is the microbiological barrier of the skin, gut, lungs and oral cavities?
Normal microbiota
What are the mechanical barriers of the gut?
Epithelial cells, lonitudinal flow of air or fluid
What are the chemical barriers of the gut?
low pH, enzymes (pepsin), alpha-defensins (ccryptdins), RegIII (lecticidins), Cathelicidin
