Flashcards in Immunology 1 and 2 Deck (63)
SCID? What is it?
Severe combined immunodeficiencySevere abnormalities of the immune system
5 things caused by the immune system going wrong?
Cancerrecurrent infectionsTransplant rejectionAllergiesAutoimmune disease
6 causes of emergence of new infections?
Global villagepopulation growthchange in human behaviourchanges in dynamic of other infections loss of natural habitatInteractions of pathogens with humans e.g. resistance
What exists between pathogens and hosts
Evolutionary arms race
Where do pathogens infect the body through?
Mucosal surfaces (airway, GI tract, repro. tract)External epithelia (wounds, insect bites, etc.)
5 components of the body that protect against infection?
Lymph nodesSpleenLymphaticsBone MarrowSkin
How does the skin protect against infection?
Physical barrier (highly packed, highly keratinised, multilayered cells)Physiological barrier (low pH (5.5), low O2 tension)Sebaceous glands (secrete hydrophobic oil, lysozyme (destroys bacterial cell wall), ammonia (anti-bacf. properties), defensins (anti-microbial peptides))
What does mucous line
All cavities that come into contact with the environment e.g. resp, GI, urogenital
How does mucous prevent infection?
Physical barriercontains IgA contains enzymes (lysozyme, defensins)Contains lactoferrin (starves invading bacteria of iron)
what do cilia do
Directly trap pathogensaid in the removal of mucous
How does commensal bacteria help to prevent infection?
Competes with pathogenic microbes for scarce resourcesProduces fatty acids and bactericidns reduce pH in large bowelSynthesise vitamin K and B12
What is bactericidin
An antibody that causes complement dependent lysis of bacteria
What does eradication of normal flora by board spectrum antibiotics often cause?
Live bacteria and east that are good for your health
Network of specialised cells, tissues and soluble factors that co-operate to kill and eliminate disease-causing pathogens and cancer cells
4 classes of pathogen
Extracellular bacteria, parasites, fungiIntracellular bacteria, parasitesViruses (intracellular)Parasitic worms (Extracellular)
See mind map study material for info about components of the immune system
Any substance that can stimulate an immune response
Family of approx. 30 different proteins
Where is complement produced?
In the liver
What do antibodies provide defence against?
Extracellular pathogens and toxins
Where do complement proteins become activated?
infected/ inflamed tissues
What do complement proteins have the ability to do?
enzymatically cleave and activate other downstream complement proteins in a biological cascade
Name for chemical messanger
Summarised role of cytokines
co-ordinates the immune system
4 examples of cytokines?
Interferons, tumour necrosis factor, chemokines, interleukins
Tumour necrosis factor
Control and directs cell migration