Immunity in homeostasis (W11)

Question 1

2 types of healthy immunity

Answer 1

steady state
inducible immunity

Question 2

steady state description

Answer 2

pre-empts inflammation so homeostasis is uninterrupted. barriers are maintained

Question 3

inducible immunity description

Answer 3

alert response to mounting danger that disrupts and damages tissue. 2 pathways:
-inflammation
-adaptive immunity

Question 4

inducible immunity - inflammation pathway?

Answer 4

PRRs over a threshold and trigger inflammation - induced innate immunity

Question 5

inducible immunity - adaptive immunity pathway?

Answer 5

antigen-specific receptors after antigen encounter trigger adaptive immunity

Question 6

components of healthy steady state immunity?

Answer 6

intact barriers
antimicrobial molecules
healthy microbiota
sleep quality
active skeletal muscle
adipose

Question 7

what can disturbance of the components of healthy steady state immunity cause

Answer 7

increased susceptibility to infections or trigger unnecessary sterile inflammation

Question 8

how does healthy skeletal muscle moderate immunity

Answer 8

major source of cytokines (myokines)

Question 9

myokines activity that maintains the immune response?

Answer 9

regulate inflammation
support adaptive response to new & recall antigens in elderly
promote innate cells (eg NKs, macrophages)

Question 10

what is used as an immune adjuvant before cancer treatment and why

Answer 10

physical therapy due to immune benefits of myokines

Question 11

what is the significance of tissue resident macrophages

Answer 11

resident macrophages have tissue-tailored homeostatic functions that maintain immunity

Question 12

why does specific immunity decline with age and what is this called?

Answer 12

immunosenescence
thymus and marrow atrophy, reducing lymphocyte diversity
reduced bioenergetics impair responses
global DNA methylation reduces survival factor production
exhausted & deteriorated T cells
less competent & mature T cells
epigenic scars from infection supressing immunity

Question 13

explain inflammaging

Answer 13

chronic low grade inflammation contributing to age-related multi-system morbidity
accumulating from danger signals from cell debris, senescent cell secretions, nutrient stress, remodelled microbiota, chronic virus, bacteria

Question 14

what is metaflammation?

Answer 14

inflammation in metabolic diseases such as obesity

Question 15

explain the process of metaflammation

Answer 15

nutrient stress in obesity -> mitochondrial dysfunction, affects liver/pancreas -> stressed adipocytes release danger signals of pro-inflammatory cytokines -> gut dysbiosis is also pro-inflammatory

Question 16

what is biological age

Answer 16

biomarkers like:
DNA methylation
pro-inflammatory glycosylation
metabolic and infection history define biological age

Question 17

what is tissue-tailored immunity

Answer 17

some tissues protected from immune activation (immunological isolation) by barriers and resident immune cells

Question 18

IBS?

Answer 18

genetic predisposition for altered intestinal ecosystem
mucosal barrier homeostasis breaks down
characterised by dysfunctional barrier, dysbiosis and inflammation
cycle of inflammatory damage, barrier breakdown and further dysbiosis

Question 19

what is immunometabolism

Answer 19

resource allocation to defence and survival, resources diverted from movement, growth and production
immune activation depends on metabolic reprogramming, usually from catabolic to anabolic

Question 20

cell metabolic programmes: catabolic and anabolic?

Answer 20

dormancy associated = catabolic
growth associated = anabolic

Question 21

catabolic vs anabolic?

Answer 21

catabolic - releases energy
anabolic - uses up energy