Lecture 8: Nonspecific Host Defense Mechanisms; The First Line Of Defense Against Pathogens

Front 1

Natural Immunity is nonspecific. What three things are part of the nonspecific host defense mechanisms?

Back 1

Phagocytes
Chemicals
Physical barriers

Front 2

Normal Flora prevents pathogens from colonizing by producing ____ toxic to other bacteria.

Back 2

bacteriocins

Front 3

Normal flora prevent pathogens from colonizing by providing competition for ____ and _____.

Back 3

nutrients and attachment sites

Front 4

normal flora prevent pathogens from colonizing by creating an unfriendly environment. (secreting ____, ____).

Back 4

acids
fatty acids

Front 5

Normal Flora is present on body without causing disease. It prevents pathogens from colonizing by what three things?

Back 5

- producing bacteriocins toxic to other bacteria
- providing competition for nutrients and attachment sites
- creating an unfriendly environment (secreting acids, fatty acids)

Front 6

Skin. ____ and _____ provide a physical barrier to microorganisms.

Back 6

epidermis and dermis

Front 7

Although the epidermis and dermis provide a physical barrier to microorganims, ____ and ____ are natural portals of entry for pathogens.

Back 7

hair follicles and glands

Front 8

Name a pathogen that pushes itself through natural portals of entry (hair follicles and glands).

Back 8

Treponema pallidum (a spirochete) causes syphilis, an STD

Front 9

Skin is tough, dry (no water, no life), ___, ____, ____, covered with normal flora.

Back 9

salty
oily
low in nutrients

Front 10

Microorganims can be ____ with epidermis

Back 10

shed

Front 11

Name a protein in the skin.

Back 11

Keratin

Front 12

Keratin (protein in skin) is a poor source of _____

Back 12

carbon

Front 13

Name three things that are naturally antimicrobial.

Back 13

- fatty acids
- acids
- sweat

Front 14

________ makes antimicrobial fatty acids with lipase

Back 14

Propionibacterium acnes

Front 15

Propionibacterium acnes makes antimicrobial fatty acids with _____

Back 15

lipase

Front 16

_____ ferment to produce acidic environment

Back 16

Staphylococci

Front 17

Staphylocci ferment to produce ____ environment.

Back 17

acidic

Front 18

Disease is more likely to occur if skin barrier is _____.

Back 18

broken
ex: surgery, puncture wounds, bites, injections, etc.

Front 19

Respiratory System. Airflow turbulent-microbes get stuck on ______

Back 19

mucosal surfaces

Front 20

______ beat towards the pharynx (up the mucosal escalator).

Back 20

cilia

Front 21

Microbes sent up to mouth/nose, expelled by coughing or sneezing, or combined with _____ and sent to _____.

Back 21

saliva
stomach

Front 22

____ destroys mucosal cells, disrupts action of the mucosal escalator.

Back 22

Smoking

Front 23

Mucous is full of ____, an enzyme that can break down peptidoglycan (a good thing).

Back 23

lysozyme

Front 24

Mucous is full of lysozyme, an enzyme that can break down ____

Back 24

peptidoglycan

Front 25

Besides mucous, lysozyme can also be found in ______

Back 25

lacrimal fluid (tears). This acts to protect eyes.

Front 26

If bacteria doesn't get sneezed or coughed out, it goes to the gastrointestinal tract. Stomach acid has a pH of ____ and is a natural barrier to pathogens.

Back 26

pH 2

Front 27

Stomach acid kills most everything, except ____ and _____, ______, ______

Back 27

Typhoid and tubercle bacilli

protozoal cysts

certain viruses, Helicobacter pylori (causes stomach ulcers, can make environment a lower pH)

Front 28

Name a virus that stomach acid can't kill.

Back 28

Helicobacter pylori

Front 29

Bile enters GI tract at _____

Back 29

duodenum

Front 30

GI tract is inhibitory to most microorganisms. Also duodenal enzymes will digest all the ____ and _____ components of microorganisms (proteins, carbohydrates, fats).

Back 30

structural
metabolic

Front 31

Name a pathogen that can get into your gastrointestinal tract. hint: it forms cysts.

Back 31

Giardia- a protozoan that forms cysts. Beavers poop it out into cold water. You drink water w/ cyst. It goes into stomach, then intestines. Cyst will become vegetative form. TROPHOZOITE form suckers. get diarrhea. lasts for 40 days.

Front 32

GENITOURINARY TRACT. Flow of urine prevents microbes from reaching ____ or _____

Back 32

kidneys
bladder

Front 33

Women get more bladder infections than men because?

Back 33

women have shorter urethra.

Front 34

pH of vaginal tract is kept low by _____ producing lactic/acetic acid as a result of glycogen fermentation.

Back 34

Lactobacillus.

Front 35

pH of vaginal tract ketp low by Lactobacillus producing lactic/acetic acid as a result of _____

Back 35

glycogen fermentation

Front 36

In ______ or _____ women, vaginal flora similar to adjacent skin.

Back 36

pre-pubescent
post-menopausal

Front 37

During child-bearing years, estrogen levels rise causing vaginal epithelial cells to secrete ____.

Back 37

glycogen

Front 38

Interferons stimulates production of _____ that interfere with viral reproduction in neighboring cells

Back 38

antiviral proteins (AVPs)

Front 39

Phagocytes include _____, ____(neutrophils, eosinophils)

Back 39

macrophages
PMN cells (polymorphonuclear)

Front 40

PMN cells inclue ____ and ____

Back 40

neutrophils and eosinophils

Front 41

____ and _____ work together to confine pathogens to site of entry and fix damaged tissue

Back 41

phagocytosis
inflammation

Front 42

opsonin

Back 42

protein found on bacterium that enhances phagocytosis

Front 43

_____ is a response to injury (chemical, physical, or living organism)

Back 43

inflammation

Front 44

What are three types of injury?

Back 44

chemical
physical
living organism

Front 45

What are four signs of inflammation?

Back 45

rubor
calor
dolor
tumor

Front 46

Rubor

Back 46

redness

Front 47

Calor

Back 47

heat

Front 48

Dolor

Back 48

pain

Front 49

tumor

Back 49

swelling

Front 50

injured cells release ____

Back 50

chemicals

Front 51

_____, _____ respond to chemical signals such as _____ and arrive at site to begin phagocytosis

Back 51

neutrophils
macrophages
histamine

Front 52

_____ forms around pus.

Back 52

fibrin walls

Front 53

Pus is composed of ____, _____, _____, _____

Back 53

plasma, tissue cells, dead bacteria, leukocytes

Front 54

______ develop from fibrin enclosing pus

Back 54

abscesses

Front 55

abscesses develop from fibrin enclosing pus (becomes a _____ if big)

Back 55

carbuncle

Front 56

Describe the process of inflammation.

Back 56

sunburn or mechanical injury introduces bacteria --> vasodilation (capillary walls open [dilate], releasing plasma) --> phagocytosis by neutrophils and macrophages --> fibrin walls form around pus --> abscesses develop from fibrin enclosing pus --> form a walled off site of injury

Front 57

Name a chemical messenger that causes vasodilation

Back 57

histamine

Front 58

Fever is an abnormally _____.

Back 58

high temperature

Baby- if go over 100oF, not good.
Child- if go over 102oF, not good.
if 104, 105, must cool the person down quickly

Front 59

Phagocytes engulfing parasites produce ____ such as ______ or _____

Back 59

cytokines (chemical messenger)
interleukin-1
endotoxins

Front 60

Phagocytes engulfing parasites produce cytokines such as interleukin-1 or endotoxins. These _____ (fever-inducers) travel in the blood to hypothalamus. What does the hypothalamus do?

Back 60

pyrogens

hypothalamus raises body temperature

Front 61

Fever results in ____ of blood vessels and an increase in overall ______

Back 61

constriction
cell metabolism

Front 62

Fever results in ____, ____

Back 62

cold skin
chills and fever

Front 63

Fever results in ______ of growth of certain microorganisms.

Back 63

inhibition

Front 64

fever results in more _____ repair and phagocytosis

Back 64

tissue

Front 65

Fever results in reduced blood borne ____ needed by parasites

Back 65

iron

Front 66

Fever results in what 5 things?

Back 66

- Constriction of blood vessels and an increase in overall cell metabolism
- cold skin, chills and fever
- inhibition of growth of certain microorganisms
- more tissue reapir and phagocytosis
- reduced blood borne iron needed by parasites

Front 67

Natural Killer Cells are like _____

Back 67

roaming assassins

Front 68

Natural Killer Cells picks out 'hits' by checking for _____

Back 68

class I MHC (major histocompatibility complex proteins)

- Natural Killer cell surface receptor forms complex with class I MHC found on most cells

Front 69

If no MHC or in reduced quantitites (as in cancer cells or virus-infected cells), Natural killer cells ____.

Back 69

kill

Front 70

Complement System is a series of ____

Back 70

proteins

Front 71

Complement System is a series of proteins. Proteins which act in a cascade (___ activates the others) to ____, _____ and _____ microorganisms.

Back 71

C3
bind, coat, and destroy

*complement system is like a dogpile

Front 72

Complement System is activated to _____

Back 72

destroy bacteria

Front 73

Give one example as to how the complement system works.

Back 73

- Phagocytes release IL-6 after eating bacteria
- IL-6 stimulates production of lectin protein- binds mannose on bacterial capsule
- mannose is present on microbial cell walls, but not mammalian cell walls
- lectin binding activates complement pathway
- complement proteins dogpile
- protein encased bacterium destroyed by lysis or phagocytosis

Front 74

When ____ and ____ bind together, activates C3, cascade occurs, complement proteins dogpile.

Back 74

Mannose and lectin

Front 75

Mannose (sugar), is just on _____ cells, not body cells

Back 75

bacterial