Immunity and Host Defense against Oral Infections (complete) Flashcards Preview

DMD 5244 (Immunity) > Immunity and Host Defense against Oral Infections (complete) > Flashcards

Flashcards in Immunity and Host Defense against Oral Infections (complete) Deck (70):
1

Which two things in the oral cavity acts as a physical barrier that prevents pathogen invasion

1. the integrity of the Oral Mucosa
2. tooth enamel

2

What are the two types of immunity that you can find in the Oral cavity

Non-specific (innate) immunity
Specific (adaptive) immunity

3

Which type of immunity in the oral cavity is non-specific and continuous
innate or adaptive immunity

innate

4

What triggers the activation of adaptive immunity in the oral cavity

a response to specific pathogen/antigen which causes an antigen-specific antibody response or a T-cell response

5

What things come from gingival crevicular fluid that assist in immunity of the oral cavity

1. Polymorphs (PMNs)
2. Complement pathway proteins
3. IgG
4. IgA

6

What is the class, function and abundance of Neutrophils

Class = Granulocyte
Function = Phagocyte, innate immunity
Abundance = 62%

7

What is the class, function, and abundance of lymphocytes

Class = agranulocytes
Function = adaptive immunity
Abundance = 30%

8

What is the class, function, and abundance of monocytes

Class = agranulocytes
Function = phagocytes (macrophages in the tissues)
Abundance = 5%

9

What is the class, function and abundance of eosinophils

class = granulocyte
function = removal or hemoliths and Ab/Ag complexes
abundance = 2%

10

What is the class, function, and abundance of basophils/mast cells

class = granulocytes
function = allergy response, inflammation
abundance =

11

What are the different soluble mediators of immunity in the oral cavity

Antibodies
Complement components
Cytokines

12

what are the antibodies that are soluble mediators of immunity in the oral cavity

sIgA
IgM
IgG

13

What is the main complement component that is a mediator of immunity in the oral cavity

C3

14

what are the cytokines that are soluble mediators of immunity in the oral cavity

IL-1
IL-6
TNF-alpha

15

From where does sIgA come from

saliva

16

What are the 4 barriers of innate immunity in the oral cavity

1. anatomic barriers
2. physiologic barriers
3. phagocytotic barriers
4. inflammatory barriers

17

What makes up the anatomic barrier of the oral cavity

the epithelial cells of the oral cavity

18

What are the three ways that epithelial cells of the oral cavity fight infection

1. act as a physical barrier
2. the production of antibiotics, cytokines, and NO
3. housing intraepithelial lymphocytes that kill the microbe

19

How do epithelial cells produce antibiotics, ctyokines, and NO

They have TLRs on their surface that recognize PAMPs, the binding of PAMPs by the TLRs signals epithelial cells to produce peptide antibiotics, cytokines, and NO

20

What are PAMPs

they are pathogen associated molecular patterns. (certain molecular patterns that are only found in pathogens)

21

What are TLRs

Toll-Like receptors (receptors on cell surfaces that recognize and bind to PAMPs)

22

What does TLR-2 bind to

Lipoteichoic acid that is found in gram + bacteria

23

what are two types of gram+bacteria that are bound by TLR-2

Actinomyces
Strep

24

What does TLR-4 bind to

lipopolysaccharides (LPS) of gram - bacteria

25

what is a type of gram - bacteria that TLR-4 binds

prevotella

26

Do oral cavity epithelial cells express receptors for sIgA

Yes

27

how does the swallowing of saliva affect immunity of the Oral cavity

it removes microbes from dental plaque and oral mucosa

28

How do pH and Temperature of the saliva affect immunity of the mouth

A rise in pH in gingivitis and periodontal disease favors putative periodontal pathogen growth
A rise in temperaure alters bacterial gene expression, and immune evasion

29

what is the normal pH in the mouth

6.9

30

What things found in saliva are antimicrobial in nature

lactoferrin
lysozyme
Myeloperoxidase system
salivary peroxidase system
antimicrobial peptides
complement
leukocytes
sIgA

31

What is lactoferrin of saliva and what does it do in oral cavity immunity

an Iron binding molecule that is bacteriostatic (stops bacteria from reproducing)

32

What is lysozyme of saliva and what does it do in oral cavity immunity

it is a basic protein that breaks down bacterial structure

33

what bacteria is the lysozyme of saliva effective against

S. mutans

34

what is the Myeloperoxidase system of saliva and what does it do in oral cavity immunity

it is a bactericidal generating halide, H2O2 in PMNs migrate to the gingival crevice to start inflammatory response

35

What is the salivary peroxidase system of saliva and what does it do in oral cavity immunity

It is a bactericidal generating thiocyanate that produces H2O2

36

What are the main antimicrobial peptides that are found in saliva

histatins and defensins (alpha and beta)
(they are small cationic peptides with antimicrobial activity)

37

what are histatins and what do they do for oral cavity immunity

they are histidine rich peptides with broad anti-fungal and anti-bacterial activity

38

what are defensins and what do they do for oral cavity immunity

they have broad anti-fungal, bacterial and VIRAL activity

39

what to Beta defensins do specifically

protect mucosal surfaces

40

what does the complement from saliva do for oral cavity immunity

Breaks down C3 derived from GCF (gingival Crevicular fluid)

41

What do leukocytes from saliva do in oral cavity immunity

secrete alpha defensin
phagocytosis
microbial killing

42

what happens to leukocyte activiy in the oral cavity with inflammation

it increases

43

What is sIgA from saliva and what does it do in oral cavity immunity

it is the major Ab in saliva and it inhibits microbial adherence, agglutinates bacteria, and neutralizes viruses

44

What is the phagocytic barrier involved in immunity of the oral cavity

the presence of phagocytes that destroy pathogens

45

how do phagocytes destroy pathogens

1. they bind the pathogen using cell surface receptors
2. engulf the pathogen in a phagosome
3. pump in toxic reactive oxygen and nitrogen intermediates to kill the pathogen

46

What are the oxygen-independent methods phagocytes use to kill pathogens

Lysozyme
Defensins
Lactoferrin
Proteolytic and hydrolytic enzymes

47

what does lysozyme do

breaks down cell wall components

48

what are the oxygen dependent methods phagocytes use to kill pathogens

Hydrogen peroxide
superoxide anion
hydroxyl radical
myeloperoxidase
hypochlorite
hypohalite
Nitric oxide

49

what is CGD

chronic granulomatus disorder, a disorder where phagocytes lose their ability to completely eliminate engulfed pathogens.

50

what are the treatments for CGD

antibiotics (high dose, long term)
IFN-y injections to activate macrophages

51

what Abs does the Gingival crevicular fluid have

IgG, IgA, and IgM
(saliva has sIgA)

52

What are some key characteristics of IgG

1. monomer
2. 70% of total Ab
3. crosses the placenta and protects fetus
4. activates complement
5. major opsonizing Ab
6. protects gingiva and gingival portion of crown

53

What are some key characteristics of IgM

1. Pentamer
2. 10% of total Ab
3. first Ab generated against any Ag
4. predominant Ab produced by the fetus
5. Ab for carb antigens (ABO)
6. protects gingiva and gingival portion of the crown

54

What are some key characteristics of IgA

1. in serum as monomer, in secretions as dimer
2. lines the oral cavity and doesn't allow pathogens to adhere
3. mucosal immunity
4. sIga distinguishes between commensals and pathogenic molecules

55

what is immune exclusion

the ability of antibodies (sIgA) to tell between commensal and pathogenic molecules

56

what mediates humoral mucosal immunity

sIgA

57

there are two classes of IgA. IgA-1 and IgA-2. what is the difference

IgA-1 is more concentrated in plasma (both equal in saliva)
IgA-1 is directed against protein antigens
IgA-2 is directed against carb antigens

58

what does the M-cell of the mucosal immune system do

captures the Ag and delivers it to DCs. this signals IELs to migrate to mesenteric lymph nodes

59

what is the main difference between oral and gut mucosal immunity

gut has MALT mouth has Oral lymphoid foci

60

what are the two main immunologic functions of the mucosal epithelium

1. provides physical barrier between the body and microbes
2. confers the first line of immune defense against the microbes

61

what type of T-cells are most IEL's (intraepithelial lymphocytes)

CD8+

62

what do DC (dendritic cells) do in oral mucosa

sample between epithelial cells for Ags

63

what are the three functions of the oral mucosal immune system

1. respond to harmful organisms
2. regulate influx of immune cells
3. prevent inflammatory tissue destruction

64

what happens to commensal bacteria if the homeostasis between them and the mucosal immune system becomes unbalanced

they become surrogate pathogens and stimulate a chronic inflammatory response

65

what does dental plaque at the gingival margin result in

acute inflammation

66

what does acute inflammation do to GCF

it increases the flow of GCF

67

an ecological imbalance between the endogenous flora and host immune response results in

dental caries and periodontal disease

68

what causes dental caries

frequent consumption of fermentable carbs. which is used by S. mutans and that gives off acid which degrades enamel

69

what do M-cells do the the mouth

they capture antigens and deliver them to Dendritic cells, those then cause the secretion of IgA

70

what do mucosal epithelial cells secrete as a non-specific shield to prevent microbe damage

mucins
defensins
trefoil peptides
acquired enamel pellicle
lysozyme
NO