Lecture 16--intro to human immune system

Question 1

5 areas med where immunology important

Answer 1

allergies, autoimmune disorders, transplantation, cancer, infectious disease

Question 2

3 ways body respond to microbes

Answer 2

tolerance, segregation, combat

Question 3

fxns of human immune sys:

Answer 3

1) create phys/bio/chem barrier that prevents foreign material enter sterile body sites 2) distinguish self and non self 3) create a memory of prior encountered foreign stuff so later exposure can respond faster and stronger

Question 4

2 basic mechanisms of immunity:

Answer 4

innate and acquired

Question 5

non-specific defense, respond same way regardless of microbe type (no memory); involves external barrier and internal cell/bio defenses

Answer 5

innate

Question 6

specific defense, individual response designed for each diff microbe, has memory; involves Ab-mediated (humoral) immunity and cell-mediated immunity

Answer 6

adaptive (acquired)

Question 7

what are diff external entry barriers?

Answer 7

structural defenses (skin, mucous membranes),mechanical defenses (urine, tears, saliva), microbial defenses (gut bacteria), and biochem defenses (eg. lysozyme)

Question 8

how structural defenses work?

Answer 8

dry salty enviro, removal through dead skin cell loss, hard to penetrate

Question 9

internal cell/bio defenses kick in when ___

Answer 9

pathogen overcomes surface barriers

Question 10

what are the diff internal cell/bio defenses?

Answer 10

interferon, phagocytosis, inflammation, complement, fever

Question 11

interferon has anti-____ action

Answer 11

viral

Question 12

what is interferon?

Answer 12

small peptide produced by virus infected cell, tells other cells to make antivirus; host specific and virus nonspecific

Question 13

3 diff types INF:

Answer 13

alpha and beta (antiviral), gamma (stim phagocytic cells and helps regulate parts of acquired immune response)

Question 14

what is phagocytosis?

Answer 14

process which certain cells digest/remove dead tissues and foreign material penetrating external surface barrier

Question 15

what are phagocytes?

Answer 15

WBC: monocytes/neutrophils/eosinophils (bloodstream), macrophages (monocytes migrated into deeper tissues), dendritic cells (close to body surface)

Question 16

relative proportion of WBC that helps diagnose disease is called:

Answer 16

WBC differential

Question 17

bacterial infection often give ___ in total WBC, ___ in neutrophiles, ___ in bands

Answer 17

increase in all

Question 18

viral infections give ____ total WBC, ___ lymphocytes

Answer 18

decrease; increase

Question 19

increase in total WBC also due to :

Answer 19

leukemia, trauma, stress

Question 20

decrease in total WBC also due to:

Answer 20

radiation therapy, bone marrow disease

Question 21

mech of phagocytosis:

Answer 21

1) bacterium attached to mem evaginations (pseudopodia) 2) ingested, form phagosome 3) fuse with lysosome 4) enzymes digest captured material 5) digestion products released from cell

Question 22

is phagocytosis specific?

Answer 22

nope

Question 23

what are pattern recognition receptors

Answer 23

proteins on surface of phagocytes that recognize characteristic cules in microbes and not in host cells

Question 24

what happens to digestion products?

Answer 24

adsorbed and further degraded, may irritate surrounding tissues when there is lots

Question 25

how bacteria defend selves?

Answer 25

produce capsular polysacc, secrete toxins that kill phagocytes, escape and grow in the cytoplasm (eg. Listeria)

Question 26

how to kill parasite?

Answer 26

eosinophils secrete toxic protein perforate parasite wall

Question 27

how to kill virus?

Answer 27

NK cells recognize virus infected cell and destroy by degradative enzymes

Question 28

rapid bio response to tissue damage

Answer 28

inflammatory response

Question 29

classic features inflammation

Answer 29

redness, swelling, heat, pain

Question 30

inflammation overview

Answer 30

1) tissue injury trigger release of chem signals (ie. histamine) 2) dilation and ^ leakiness of local BV, migration of phagocytes to area 3) phagocytes consume microbes and debris, tissue heals

Question 31

what does histamine do:

Answer 31

vasodilate (redness, heat), increase leakiness of BV (edema), stim nerve endings (pain)

Question 32

what does prostaglandin do?

Answer 32

vasodilate, fever, ^ sensitivity to pain, atttract phagocytes and other repairing cules/proteins

Question 33

aspirin and ibuprofen block synth of:

Answer 33

prostaglandin

Question 34

use of corticosteroids for inflammation:

Answer 34

multi effects on cells, suppress inflammatory chem

Question 35

acute inflammation?

Answer 35

immediate/beneficial, resolve <2 wks once cause removed or healed, no long term consequence

Question 36

chronic inflammation?

Answer 36

delayed, potentially harmful; persistent injury/microbe, or other condition, slow to resolve; tissue damage, scarring

Question 37

a family of around 30 diff proteins in blood serum, make up 10% total serum protein

Answer 37

complement (complement the action of Ab)

Question 38

3 fxn of complement?

Answer 38

1) make phagocytosis more efficient via opsonization 2) MAC 3) regulate inflammation/immune response

Question 39

what is opsonization?

Answer 39

coat bacterial cell surface w/ complement protein, receptors on macrophage recognize complement and swallow efficiently

Question 40

bio response to external/internal pyrogenic agents

Answer 40

fever

Question 41

external pyrogen examples:

Answer 41

bacterial LPS, fungal wall comps

Question 42

internal pyrogen examples:

Answer 42

chem released from phagocytes

Question 43

pyrogens trigger increased ___ production in the ___

Answer 43

PG; hypothalamus (results in ^ hypothal thermoregulation)

Question 44

benefits of fever:

Answer 44

inhibit growth of temp-sensitive microbes, reduce availability of nutr. req. by microbes, ^ metabolic activity of phagocytic cells, stim. acute inflammation + INF production