lecture4

Question 1

psychoneuroimmunology

Answer 1

mind and behaviour relate to brain function & immune system function
- fake flower induces allergic reaction

Question 2

conditioned immunosuppression

Answer 2

related to learning theory.
US causes UR with no training.
pair CS and US, CS can cause UR, even tho not really related.
sugar water w decrese immune function drug.
conditioned immunoenhancement

Question 3

immune system

• function?
• memory?

Answer 3

defend the body. detect self v non-self

- immunological memory. protect. vaccine - remembers virus & can better deal with it next time it comes about.

Question 4

white blood cells

Answer 4

monocytes

lymphocytes - t-cell ,b-cell.

Question 5

t-cell how it works

Answer 5

• macrophage ingests pathogen, sticks pieces on cell surface.
• t-cell binds to piece on macrophage.
• causes macrophage to release interleukn-1. = stimulates helper-t cell.
  stimulated helpter-t releases interleukin-2 = acts on self to proliferate.
• recruit cytotoxic t-cell to destroy foreign invader.

Question 6

lymph nodes in body

Answer 6

filters lymph, cells gather there if they picked up antigen. look thru library of Ab to see if something will respond to it.
lymph nodes swell if looking for Ag to attack.

Question 7

b- cell mechanism

Answer 7

macrophage takes in pathogen, present antigen. t-cell bind, release Il-1, t-cell release il-2. t-cell binds to b-cell - release b-cell growth factor = proliferation of b-cell.
b-cell produce anitbody, specific bind to antigen.

Question 8

ab recruit what?

Answer 8

complement to destroy cells.

Question 9

3 relevant Ig classes

Answer 9

IgG: crosses placenta - cross immunological protection to offspring
IgA: mucosal; used in stress studies
IgE: antibody of allergy and antiparasitic activty

Question 10

3 features of acquired immunity

Answer 10

1. specially target new pathogen ( proliferation doesnt happen unless exposed)
2. takes time (few days to make Ab)
3. repeated exposure enhances immune response

Question 11

innate immunity

Answer 11

non-specific; macrophage engulfs
first point of entry = mucosal tissue.
capillaries loosen to get macrophages to pathogen
inflammation - fluid migration, damage to cardio system signals innate immune response.

Question 12

effects of stress on immune system

Answer 12

suppress lymphocytes: reduce formation, suppress release
inhibit Ab formation
disrupt lymphocyte communication - IL1,2 b-cell GF.
inhibit innate immune response

Question 13

glucocorticoid effect on immune system

Answer 13

shrunken thymus gland (age and sex hormones also decrease thymus gland)
remove lymphoctes from circulation
kill lymphocytes
shuts down HPA to inhibit immune function further.

Question 14

why suppress the immune system during stress?

• short term?
• long term?

Answer 14

short term - actually increase immune system. lymphocytes better at releasing ILs, more sensitive to ILs. mediated by adrenaline.
long term stress = glucocorticoid action. immunosuppression.

Question 15

why not enhance immune system during stress?

Answer 15

too hyperactive immune system = autoimmune disease.
autoimmune evidence:
- activate A but not Gc
- removal of adrenal glands produces Cushing’s
- spontaneous autoimmune due to malfunction of Gc response

Question 16

autoimmune treatment

stress and autoimmune

Answer 16

• steroids can decrease immune activity. = autoimmune subsides
• short, frequent bursts of stress heighten cortisol without letting it fall = higher stress = higher adrenaline = extra high immune fxn.

Question 17

chronic stress & disease risks.

Answer 17

social support and isolation. fewer social relationships = shorter life expectancy.
lower immune response to vaccines.
social support important for maintaining good health QUALITY not quantity

Question 18

stress & common cold

Answer 18

fewer mucosal antibodies

more stress = 3x more likely of developing a cold.

Question 19

chronic stress and disease risk
AIDS
- Gc effect on disease & progression. 
what is retrovirus? 
coping w denial

Answer 19

AIDS - more glucocorticoids = increased risk of HIV infection progressing to AIDS.
retrovirus - inserts into DNA, attacks when body is weak. CD4 count is 200/L w HIV; normal 1000/L
HIV + Gc = t-cell affected more quickly. stress hormones cause more quick infection.

coping w denial, little social support, social inhibition, stressors = succumb to diagnosis more when coping this way.

Question 20

latent virus

Answer 20

dormant
herpes virus
replicate when immunocompromised

Question 21

stress and cancer

• animal studies
• tumor growth thru immunity

Answer 21

stressful lab condition = tumor grows faster than in less stress condition
- natural killer cells decrease w stress. they function to prevent tumor/rogue cancer cell growth

Question 22

stress effects thru non-immunity

Answer 22

tumors require energy, rapidly dividing. take energy from blood.

• call for angiogenesis (helped by glucocorticoids)
• absorbing glucose: increase tumor growth in animal that already has tumor

Question 23

human studies of stress & cancer

Answer 23

no definitive link btw stress and cancer.
melatonin- protective against cancer.
maybe personality indirectly associated with cancer - low conscienciousness

Question 24

stress and cancer progression
- coping mechanism
david spiegel study

Answer 24

fighting spirit vs depression & denial

• fighting = live over a year longer.
• david spiegel: treatment vs treatment + therapy = therapy lived 18 months longer.
• found this was probably due to greater compliance to treatment plan

Question 25

glucocorticoids & stress and cancer - spiegel study

Answer 25

higher levels of Gc =/= shorter survival. there was variation between each group.

Question 26

immune system, stress & cancer - spiegel study

Answer 26

therapy group had more natural killer cells

Question 27

misinterpretation of SIDS

Answer 27

thought babies dying of sids had enlarged thymus because “normal” babies actually died of malnourishment so had tiny thymus.
status thymicolympathicus