immunology Flashcards
what is inflammation?
- Swelling, redness, heat and pain.
Cells signalled to move to an area that has been damaged. The more things that move there increases the swelling. Redness and heat is from blood.
types of inflammation?
ACUTE
- Fast
- Injury
- Resolves fast.
CHRONIC
- Long term
- Disease process / injury
- Unresolved inflammation
SYSTEMIC
- Long term
- Low level
- Unresolved inflammation.
what do cytokines do?
activate other immune cells.
what do chemokines do?
drive motion or movement of other cell so they come into that area.
acute inflammation steps.
DANGER SIGNAL - Injury – fungi, bacteria coming into body.
Cells that are in that area receive signals. This produces chemical signals.
CYTOKINE AND CHEMOKINE - Including cytokines and chemokine. Cytokine – activate other immune cells. Chemokines – drive motion or movement of other cell so they come into that area.
RECRUITMENT OF CELLS AND PHAGOCYTOSIS – what we can see is the capillaries become leakier. Junctions become leakier from the chemical signals. Cells pootling and squeeze through to go to the tissue following the signals. Cells are highly phagocytic – engulf invading micro to dissolve them.
RESOLUTION OF INFLAMMATION – so that this does not keep happening.
three immune cells.
Macrophages – “big eater” eat and kill.
Neutrophils – Fast come into that area eat things. Puss = neutrophils are dead.
Lymphocytes – t and b cells. Come into sight of inflammation.
immune molecules
- Cytokines – activating.
- Chemokine s- mobilising other immune cells
what does bone marrow do?
nesury school for our immune cells. Stem cells found in bone marrow. Can turn into myeloid to turn into macrophages or neutrophils. Or lymphocytes.
non-immune molecules.
Hormone – produced in brain.
Angiogenic molecules – drive new blood vessel formation.
Acute phase proteins – in liver to help fight acute infection
macrophages function.
Grow up in the bone marrow (with the other immune cells).
Some we know will stay in the tissue.
Live in blood circulation as monocytes. Immature macrocytes.
Mature into macrophages as they move into tissue
Phagocytose pathogens and destroy them.
Produce molecules Activate and recruit other immune cells. (cytokines and chemokines)
how we detect pathogens?
Macrophages have receptors to detect: self vs non-self.
Pattern recognition receptors on macrophage. Able to recognise. PAMPs found on pathogens that are not usually found in our own cells.
neutrophil function.
Grow up in the bone marrow.
Circulate in the blood. Rapidly produced in bone marrow after infection or injury.
Leave the blood and enter the tissue. Recruited out of the blood when needed. Chemokines that are produced by macrophages attract passing neutrophils. Chemokines drive this whole process.
How does a neutrophil fight a pathogen?
- Phagocytosis (eating them)
- Degranulation (release toxic chemicals)
resolving an immune response.
Macrophages also have wound healing abilities.
When talking about resolution of inflammation. Has to do with organs and non-immune responses.
Inflammatory response are not just local.
Cells activated during an immune response travel through the blood making cytokines and chemokines. Activates cells in other organs to help fight the infection
Describe the possible consequences of unresolved inflammation.
Damage to the underlying tissue.
how does exercise change the frequency of circulating immune cells.
Neutrophils, increase the number of cells. peak increase at 2-3 hr post ex. start to go down after 6-9hr.
mechanisms of neutrophils
more blood - increased blood flow in exercise = more cells.
more cells made - increased plasma cortisol during E. these influence how the bone marrow make cells. therefore need more neutrophils.
more cells released - Demarginating from blood vessels in spleen, liver, lung blood vessels during exercise.
what hormones are released during exercise?
Release of catecholamines (adrenaline) and glaucochroites (cortisol) during exercise.
- Cortisol increases neutrophil production in bone marrow = early phase, neutrophilia.
- Gets them up really quickly post exercise.
how does exercise change the function of circulating neutrophils?
- Increased killing ability (degranulation = release of toxins)
- Increased tissue migration potential. They can get out of blood vessels and into tissue quicker.
- Increased ability to respond to catecholamines and glucocorticoids. Respond better.
how exercise affects neutrophils ability of phagocytosis?
After acute exercise, more neutrophils are able to phagocytose. BUT per cell, they are less good at it than in an infection.
After chronic exercise – phagocytosis activity decreases.
why do endurance athletes differ with immunity.
Endurance athletes have lower frequency of circulating immune cells
- immune depression (lower numbers, decreased function). Consequence of training. Higher risk of infection.
Immune depression means increased infection risk
- Athletes need to take extra care to avoid infection
how does the temperature effect the immune system in exercise?
HEAT
- If athletes core temperature is over 39 degrees:
- Increased circulating cell frequency.
- Increased cell function.
COLD
- Suppressed immune function
how does the altitude effect the immune system in exercise?
Limited effect. No much at all. Effects red blood cells but not white – immune.
how does pollution effect the immune system in exercise?
Nobody really knows.
2008 Olympic – athletes had stuff in lungs.
