Reading...
Play button
Play button
Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
53 Cards in this Set
- Front
- Back
|
Hyaluronidase
|
increased tissue permeability
|
|
|
Collagenase
|
destruction of connective tissue
|
|
|
Protease
|
destruction of cell membrane
|
|
|
Leukotoxin
|
- destruction of leukocytes
- produced by Aggregatibacter actinomycetemcomitans in aggressive periodontitis |
|
|
Phospholipase A
|
activates prostaglandins
|
|
|
Nuclease
|
breaks down nucleus
|
|
|
Neuroaminidase
|
helps spread of bacteria through tissue
|
|
|
IgA/IgG proteases
|
destroys immunoglobulin
|
|
|
Catalase
|
decreases PMNs killing of bacterium
|
|
|
Fibrinolysin
|
allows spread of bacterium
|
|
|
Bacterial exotoxins
|
- proteins released by live bacteria that cause tissue destruction
- gram + and gram - |
|
|
Bacterial endotoxins
|
- part of cell membrane of gram - bacteria
|
|
|
Endotoxins causes tissue destruction by...
|
- cytotoxicity
- complement activation - bone destruction |
|
|
Bacterial antigens stimulate immune response which can also cause tissue damage by...
|
- complement activation
- lymphokine production - acute inflammatory response (i.e. leukocytic hydrolases) |
|
|
Clinical examples of gingivitis
|
- edema
- redness - bleeding |
|
|
Initial microscopic tissue changes in gingivitis
|
1) Hyaluronidase causes widened intracellular space sin epithelium lining gingival sulcus. Get increased penetration of bacterial products into CT. Get increased outflow of gingival fluid from CT.
2) Basement membrane destruction by collagenase results in ulceration of epithelial lining of gingival sulcus which causes gingival bleeding on probing. 3) Bacteria now can have direct contact with connective tissue and blood vessels. Bacteria invasion is limited. |
|
|
Initiation of acute inflammatory response
|
- Mast cell activation
- PMN activation |
|
|
Activated mast cells release...
|
- Histamine
- SRS-A - Heparin - Bradykinin |
|
|
Mast cell activation and release of stuff results in...
|
- vasodilation
- increased gingival redness and also blue-ish tinge - edema and gingival fluid increase |
|
|
PMN activity:
|
- chemotaxis
- phagocytosis of bacteria - release of primary and secondary granular enzymes formation of PMNs wall in sulcus lining |
|
|
How do PMNs kill bacteria intracellularly?
|
- oxygen metabolites, i.e. superoxide anion
- lysosomal granules containing defensins and proteases |
|
|
Cells of the basophil series in gingivitis
|
- mast cells
- neutrophils (PMNs) |
|
|
Cells of the agranular series in gingivitis
|
- lymphocytes
- monocytes |
|
|
As gingivitis develops, the acute inflammatory response continues and chronic inflammatory response is added. What two things characterize the chronic inflammatory response?
|
- lymphocytes
- capillary proliferation |
|
|
B cells
|
- derived from bone marrow
- produce antibodies to bacterial antigens - humoral mediated immune response |
|
|
B cells are activated by ____ processed by _____.
|
B cells are activated by ANTIGENS processed by MACROPHAGES.
|
|
|
B cells involved in periodontitis
|
- Plasma cells - produce antibodies to specific antigens
- Memory cells - memory is dependent on interactions with T cells |
|
|
Patients with periodontal disease have high serum levels of ____ (which immunoglobulin) specific for ______ _______.
|
Patients with periodontal disease have high serum levels of IgG specific for PLAQUE BACTERIA.
|
|
|
IgG
|
70-75% of total gives initial defense
|
|
|
IgA
|
seen in gingival fluid and saliva
- stops bacterial adherence to surfaces |
|
|
IgM
|
causes bacterial agglutination and lysis in blood stream
|
|
|
IgD
|
- small amounts
- controls B cell production |
|
|
IgE
|
- small amounts
- allergic reactions |
|
|
T cells
|
- cell mediated response
- produce lymphokines as a result of interaction with bacterial antigens |
|
|
T cells are activated by ____ processed by ______.
|
Antigens, Macrophages
|
|
|
T cells that predominate in gingivitis
|
Amplifier
Memory Helper Suppressor Killer Delayed |
|
|
Lymphokines in periodontal disease
|
IL-1
TNF MAF MIF CTX |
|
|
IL-1
|
interleukin-1 causes inflammation, and bone and tissue destruction
|
|
|
TNF
|
tumor necrosis factor
|
|
|
MAF
|
macrophage activation factor
|
|
|
MIF
|
macrophage migration inhibitory factor
|
|
|
CTX
|
leukocyte derived chemotactic factor
|
|
|
Complement
|
A group of 20 or more proteins that potentiate the immune response by activation of the complement cascade.
|
|
|
Direct activation of complement is by...
|
antibody-antigen complexes
|
|
|
Indirect activation of complement is by...
|
IgG, IgA, IgE, endotoxin, polysaccharides, and bacteria
|
|
|
Activated complement causes:
|
Cytotoxicity
Chemotaxis of PMNs Increased vascular permeability Macrophage attraction |
|
|
Which two complement proteins activate mast cells?
|
C3a and C5a
|
|
|
In early gingivitis ____ are the dominant lymphocytes, but eventually _____ dominate.
|
T cells,
B cells |
|
|
Macrophages contribute to inflammation and immune response by:
|
1) Processing antigens that stimulate lymphocytes
2) Phagocytose antigens and bacteria 3) Produce prostaglandins, stimulating osteoclasts and causing acute inflammation 4) Produce IL-1 5) produce collagenase |
|
|
Eosinophils and their role in periodontal disease
|
Minor role, if any, in periodontal disease by release of histamine, bradykinin, and prostaglandins.
|
|
|
Host Derived Tissue Destruction
|
Matrix metalloproteinases (MMPs)
|
|
|
MMPs
|
- derived from fibroblasts, leukocytes, epithelial cells
- induced by bacteria and IL-1 - include collagenase, elastase - increased in periodontitis - inhibited by doxycycline |
|
|
Progression to periodontitis
|
- Inflammation and tissue destruction proceeds apically with loss of collagen fibers attached to cementum and bone. Epithelial lining of pocket moves deeper into periodontium.
- Bone loss due to activation of osteoclasts by prostaglandin E (PGE) and IL-1 produced by macrophages, and IL-1 produced by lymphocytes. - Inhibition of osteoblasts. |
