Innate Defences Flashcards
What is the innate immune system?
The immediate part of the body that defects pathogens
What are some examples of innate immunity in the body?
Phagocytes, NK cells
How does the skin protect against pathogens
Outer keratinised layer prevents entry
Flora on the skin competes with invaders for both space & Nutrients
How does the process of inflammation work?
Tissue damage triggers mast cells to release histamine from histamine granules
Histamine diffuses into the capillaries causing dilation, as plasma leaks into the tissue the area will swell
Complement proteins and other chemicals attract phagocytes which will engulf and digest any dead or foreign cells
How do mucous membranes protect against pathogens?
Mucous contains:
Lysozymes which lyse bacterial cell walls and are bactericidal for many Gram+ bacteria
Lactoferrin, an iron binding protein which sequesters (isolates) free iron
What are phagocytes?
Cells which protect the body by ingesting foreign particles, bacteria or dead/dying cells in a process called phagocytosis
How does phagocytosis work?
Microbe is ingested before being enzymatically destroyed, with any waste products being eliminated
