Immunology 01- Innate Immunology Flashcards
def. pathogens
agents that cause diseases
def. immune system
body’s system of defenses against pathogens
def. innate system
set of defences that are activated immediately upon infection and the response is the same wether or not the pathogen has been encountered previously
Invertebrate external defense + def.
exoskeleton- though, dry barrier that keeps out the bacteria and viruses
insect digestive system is protected by
additional physical barriers, low pH and secretion of lysozyme
def. lysozyme
enzyme that breaks down bacterial cell walls
def. phagocytosis
cellular ingestion and digestion of foreign substances
what do recognition proteins in phagocytosis do? what does the recognition trigger?
bind to molecules only found in pathogens, recognition triggers the production of antimicrobial peptides that bring about the destruction of the invaders
Vertebrate innate immunology coexists with
the system of adaptive immunity
mammals external innate defense barriers
skin, mucous membranes
what do mucous membranes do? ,give e.g. of the systems
protect organ systems open to the external environment, e.g. digestive, respiratory, reproductive & urinary systems
def. cilia
located on cells lining the respiratory tract, sweeps the mucus and any microbes upwards and out, helping to prevent lung infections
name the innate immune cells and where they are found
white blood cells, found in interstitial fluid and in blood
name phagocytic cells
neurophils, macrophages
describe macrophages
big eaters, big phagocytic cells that wander through the interstitial fluid eating any bacteria and virus infected cells they encounter
def. NK cells
Natural Killer cells attack cancer cells and virus infested cells by releasing chemicals that lead to cell death
def. antiviral proteins
proteins that either attack microbes directly or prevent their reproduction
def. Interferons
proteins produced by virus-infested cells to limit the cell-to-cell spread of viruses
describe the steps of the interferon mechanism against viruses
- virus infects a cell and causes 2. the interferon genes in the cell’s nucleus to be turned on; 3. the cell synthesises the interferon and then dies, but 4. its interferon molecules may diffuse to neighbouring healthy cells, 5. stimulating them to produce antiviral proteins
def. complement system
group of 30 different kinds of proteins that circulate in an inactive form in the blood
Which components of the innate immunity actually help prevent infection?
exoskeleton/ skin, mucous membrane
Which components of the innate immunity come into play only after infection has occurred?
phagocytic cells (neutrophils & macrophages), NK cells, defensive proteins (interferons & complement system)
