host responses to periodontal bacteria Flashcards
(131 cards)
1
Q
where does bacteria attach and colonize to induce damge to perio tissues
A
in the gingival crevice and some invade perio soft tissue
2
Q
how can a bacteria cause perio damage
A
- Release substance to directly damage host cells
- Activate host’s own inflammatory and immune systems leading to host tissue damage (most damage)
3
Q
what are the major microbial virulence factors
A
Ability to invade epithelium
Direct cytoxic effects of bacterial metabolic waste
Damaging bacterial enzyes
Immunostimulatory molecules
4
Q
what are the bacterial metabolic wastes that can damge periodontal tissue
A
Ammonia
Indole compounds
Fatty acids (propionic and butyric acids)
HS
5
Q
what bacterial enzymes can damage periodontal tissue
A
Leukotoxin
Gingipains
6
Q
what are the immunostimulatory molecules
A
LPS from gram negative Lipoteichoic acids from gram positive Gingivapins Formylpeptides Other surface antigens
7
Q
what is the action of leukotoxin
A
Kills neutrophils and macrophages (phagocytic cells)
8
Q
what doe Gingipains do
A
Degrade many proteins
- interleukins
9
Q
what is the action of formylpeptides
A
Interact with phagocytic cells to induce chemotoxis
10
Q
what is the passive protection of the periodontium
A
PRevention of bacterial entry via periodontal eptihlium
- shedding of outer layer
11
Q
what is the first line of active defense of the periodontum
A
Innate/nonspecific immune system
12
Q
what is the second line of active defense
A
Acquired (adaptive) immune response - specific
13
Q
what stops bacteria from entering in the first place
A
Shedding of epithelial cells into the oral cavity
intact epithelial barrier
Possitive fluid flow into the gingival crevis
14
Q
what epithlium is crutial for stopping bacterial entry
A
Junctional epithelium
15
Q
what is the roll of connective tissue in preventing bacterial entry
A
Lots of vessels to flow and flush out bacterium
16
Q
what does gignival crevicular fluid originate as
A
Gingival tissue interstitial fluid
17
Q
what happens to the vessels of the periodontum connective tissue with inflammation
A
dilation leads to opening a vessels and leaking
- plasma and compliments leave
- adema and redness
18
Q
what is included in the innate immune repsonse
A
Complement system
Oral mucosa production of anti-microbial peptides
Oral epithelium produced pro-inflammatory cytokines
Antimicrobial effects of antibodies, lactoferrin, lysozyme
Phagocytic function of neutrophils and macrophages
19
Q
what does the complement system lead to
A
Induces bacterial lysis
promote phagocyte recruitment (chemotaxis)
promote phagocytic by opsonization of bacterial
Activates mast cells, increasing
20
Q
what are universal signs of infection
A
Il-1Beta and TNF-alpha
21
Q
what do IL-1 beta and TNF-alpha do
A
Recruit inflammatory cells
22
Q
what does Il-8 do
A
attract neutrophils in early stage of infections
23
Q
what does adaptive immunity respond to
A
BActerial Ag
24
Q
what are the halmarks of adaptive immunity
A
Ag recognition
Immune memory
Clonal expansion
25
do antimicrobial compounds only kill bacteria
No, kill fungi too
26
what is the host defense hierarchy
Serum complement
Neutrophils (acute inglammation)
Monocyte/macrophages (chronic inflammation)
Lymphocytes (systemic)
27
where in the mouth can bacteria colonize
Supra and subgingival environments
28
what are the supragingival environments that bacteria can colonize
```
Tongue
Oral mucosa
Tonsils
Saliva
Supragingival plaque
Others
```
29
what are the subgingival environments that bacteria can colonize
Periodontal soft tisse
Dentinal tubules
Furcations
Subgingival calculus
30
how long does it take for neutrophils to begin fighting bacteria
1/2 hours
31
what are monocytesand macrophages life length and location
Long life cels that are preposisioned in tissue
32
what are the actions of monocytes and macrophages
phagocytize and make biochem mediators
| present antigens to the acquired immune response on MHC for the lymphocyte
33
what kind of bacteria tend to be subgingival
anaerobic
34
what kind of bacteria tend to supragingival
anaerobic
35
what is the roll of SecA in saliva
Prevents bacteria attachment
36
what is the roll of histatins
antimicrobial peptide
37
what covers the oral mucosa
mucous coat
38
what is the action of mucins and agglutinin
cause bacteria to clump together and fall out of solution
39
what response do toll-like receptors work in
Induce the innate immune response
40
what do toll-like receptors recognize
Conserved microbial-associated molecular patterns (LPS, lipoteichoic acid and flagellae)
41
what cells express Toll-like receptors
all cells including:
- epithelial cells
- PMNs
- monocytes
- macrophages
42
what do TLR's signal for cells to do
Produce cytokines, chemokines, antimicrobial peptides, NO and eicosanoids
43
what happens what your immne system senses LPS
```
Complement activation
Macrophages secrete cytokines
lymphocytes devide
B cell mitogen activity
Bone resorbs
secretion of proteoglycans and TNF-alpha
```
44
what is the Classical pathway for the complement system
uses antibodies to sense
45
what is the alternative pathway for the complement system
uses bacterial celll wals
46
what does complement system eventually lead to
Cleavage of PR to give progenerators with specific activites
47
what do the proteins of the complement system do
direct lysis of bacteria
inflammation
Phagocytosis
48
what does opsonition of C3b do
leads to phagocytosis by macrophages
49
what are the rolls of C3a and C5a in the complement system
Chemotactic: attract neutrophils
- mast cell degranulation
- vascular permiability
50
what do cytokines do
Coordiation of Inflammatory and immune response
| - coordinate reaction to bacteria
51
what cytokines are pro-inflammatory
Il-1beta
| TNF-alpha
52
what cytokine is has chemotactic activity
IL-8
53
what do prostaglandins do
Induce vasodilation and cytokine production
54
what prostaglandin is a proinflamitory cytokin
PGE2
55
what is the roll of PGE2
induces production of matrix metaloproteinases by fibroblasts and osteoclas
56
what do metalloproteinases do
Degrade the ECM (may damage tissue)
57
what matrix metalloproteinase degrades the major structural protein in gingiva
PMN colagenase
58
how does the concentratio of matrix metalloproteinase change over time
High in inflamed gingiva than helahty gingiva
59
what do Proteinase inhibitors do
Antagonize inflammation
| inhibit degradation of matrix proteins
60
what is alpha-2 macroglobulin
Broad spectrum proteinase inhibitor
61
what is alpha-1 antitrypsin
Broad spectrum proteinase inhibitor
| inhibitor of PMN collagenase
62
what are definis
inhibit bacteria and fungi
63
what produces densins
Salivary gland epithelium
64
what des calprotein do
Inhibit bacteria dn fungi by chelating zinc
65
what produces calprotectin
Produced by epithelium, PMNs, monocytes, and macrophages
66
where do neutrophils come from
Depoyed from the blood
67
where are macrophages found
found in organs and tissues
68
where are mast cells found
Throughout the body
| - esp connective tissue subjacent to mucosal surfaces
69
what do neutrophiles look like
Mutli-lobed
70
how long do neutrophils circulate
1 day
71
what does acute inflammation or injury does
increases vascular permeability
redness
edema
increased gingival crevicular fluid flow
72
what are the cleavage products of compliment proteins
C5a, C3a
| IL-1, TNF
73
what does C5a and C3a do
acitvates mast cells to release Histomine, NO, interleukin and TNF
74
what are the action of IL-1, TNF
activates endo cells for adhesion reception to immobilize cells
75
what is the most numerous innate immune response
PMN's
76
what do PMN's contain to fight infection
Contain granules b/f going to the periphery
77
what are oxidative mechanisms by PMNs used to kill bacteria
USes ROS to form an oxidative complex
78
would PMNs create HOCl or H2O2
Prefer HOCl because it is better at killing microbes and damages host less
79
how does PMNs kill stuff
Surrounds bacteria and creates a phagosome
| - pours granules, glycolysis to decrease pH
80
what is the innate immunity
The inherent biological responses
81
what is adaptive/acquired immunity related to
Based on recognition of antigens, immune memory and clonal expansion
82
how does cell populations change in chronic periodontitis
Plasma cells(50%)> B lymphocytes > T lymphocytes
83
what kind of immunity are plasma cells a part of
Acquired immunity
84
what kind of immunity are neutrophils and macrophages part of
Innate
85
what do antigen presenting cells do
digest and present antigens to T helper cells
86
what do antigen presenting cells present antigens with
with MHC class II
87
what part of immunity are T helper cells part of
acquired immunity
88
what do Th1 Cells help to fight
```
cancer
intercellular infections( Virus and bacteria)
```
89
what do Th1 cells activate
Cytotoxic C cells
| also can kinda activate B lymphocytes
90
what immunity are Th2 cells assocaited with
humeral immunity
91
what do Th2 cells do to fiht periodontal bacteria
release antibodies
| activate B lymphocytes to make antibodies
92
what is the action of IL-10 released by Th2 cells
force B lymphocytes to mature to plasma cells
93
what can serve as an antigen
LPS
bacterial proteins
other bacterial compounds
94
what can act as a antigen presenting cell
Macrophages
| Langerhan cells
95
what do plasma cells do
create lots of antibodies
96
what is the action of B1 lymphocytes
Autoimmune dissorders to attack self
97
what is the action of B2 lymphocytes
Fight pathogens
98
what does the veriability of T cells give
Different types of immune resposnes
99
what is the important of Il-10 in immune responses
Balance between th1 and th2
100
what is the T-cell receptor made of
2 glycoprotein chains (Alpha and beta) with variable segnments
101
what do the variable segments of the T cell receptor do
Types of immune reponse
102
what happens to the TCR before and after therapy
changes before and after therapy
103
is TCR the same betwen chronic and aggressive perio
No, different
104
how are the twupes of T helper cells different
HAVE differnet cytokine progiles
105
what does Th1 secrete as a cytokine
Il-1
IFN-gama
TNF-alpha
106
what does Th2 secerete asa cytokine
Il-2, 5, 6, 10, 13
107
what all does IL-10 do to balance Th1 and Th2
slows down responses
inhibit macrophages
tells macrophages to make antibodies
108
is lots of IL-10 a stable, or unstable system
Stable
109
what activates Cytotoxic T cells
cytokines
110
what do Cytotoxic T cell respond to
Intracellular pathogens
111
what do antigens from intracellular pathogens bind to on cytotoxic t Cells
MHC 1 molecules
112
what happens when Cytotoxic T cells recognize an antigen presented via MHC1
destroy the infected
113
are there a lot of Cytotoxic T cells in periodontitis
No, because viruses and invasive bacteria are not really there
114
what triggerst humoral immunity
In response to soluble antigens
115
what activates complementation
Ag-Ab complex
116
what facilitates opsonization
Ag-Ab complex
117
what causes B cells to change to plasma cells
Th-2 cytokines
118
how do Convenstional B cels chang in helathy'treated sites
Decrease in helathy and treated sites
119
how do Autoreactive B cells change in healthy and treated sites
do not decrease after treatment
120
what does the complement system eventually form
Membrane attack complexes
121
what can antigbodies alone do
```
Block entery of toxins and viruses (IgM, IgG, IgA)
Immobilized bacteria (IgM>IgG)
Agglutinates bacteria (IgM> IgG)
```
122
what can antibodies plus complements do
Lyse bacteria
123
what can antibodies plus cells do
Opsonize bacteria, fungi for phagocytosis (IgG)
| Activates extracellular killing (IgG)
124
what is avidity
Ag-bidning differs among antibody subclasses
125
are all antibodies capable of effective opsonization or complement activation
No
126
is there more IgG2 or IgG1 in chronic periodontis
More IgG1
127
is there more IgG2 os IgG1 in agggressive periodontitis
more IgG2
128
what type of antigen does IgG2 recognize
carbohydrate antigens (LPS)
129
what do most subclassesof antibodies recognize
Protein antigen
130
what is the systemic humoral response to plaque antigens
1. antigens diffuse through junctional eptiehlium
2. langerhan cells process antigen
3. Antigen presenting cells (macrophages and langerhan cells) go to lymphocyes
4. antigen presenting cells reach lymph nodes to stimulte lymphocytes
5. perio microbe specific antibodies produced by plasma cells in lymph nodes and travel to gingiva via the blood
6. antibodies leave circulation to go to the crevice
7. antibody acts on microbes
131
how does the local cellular immune response to plaque antigens in the gingival crevice act
5. peridontically specific B cells and T cell proliferate within the lymph and blood streem
6. perio specific lymphocytes home back to the periodontium to begin cell mediated immune function
7. antibodies produced locally by plasma are controlled by Th2 cells. Cell mediated immunity mediated by TH1
