Lecture 7 questions

Question 1

what are 4 major microbial virulence factors

Answer 1

ability to invade periodontal epithelium (with A. a. and P.g.), direct cytotoxic effects of bacterial metabolic waste products, damaging bacterial enzymes, and immunostimulatoy molecules

Question 2

what are examples of bacterial metabolic waste products?

Answer 2

ammonia, indole compounds, fatty acids, and hydrogen sulfide

Question 3

what can damage bacterial enzymes?

Answer 3

leukotoxin from A. a. and ginigpains from P.g.

Question 4

what are some immunostimulatory molecules?

Answer 4

LPS (endotoxin) from gram - bacteria, lipteichoic acids from gram + bacteria, gingipains, formypeptides, and other surface antigens

Question 5

what are formylpeptides?

Answer 5

small tripeptides that have the ability to interact with receptors of phagocytic cells and induce chemotaxis

Question 6

what are the 3 mechanism of periodontal disease>

Answer 6

• prevention of bacterial entry (passive protection by periodontal epithelium), innate immune responses (nonspecific, first line of active defense), acquired (adaptive) immune responses (specific, second line of active defense…if the previous 2 don’t hold up against bacteria)

Question 7

how do we prevent bacterial entry

Answer 7

shedding of epithelium cells into the oral cavity inhibits bacterial colonization of mucosa, keeping an intact epithelium barrier, and having positive fluid flow into the gingival crevice to clear the outer epithelium

Question 8

what does gingival crevicular fluid originate as

Answer 8

gingival tissue interstitial fluid from capillaries in gingival CT

Question 9

what is associated with increases capillary permeability

Answer 9

inflammation (clinically we can see edema increase in temp and redness)

Question 10

what are the 5 innate immune response?

Answer 10

complement system, anti-microbial peptides from oral mucosa, pro-inflammatory cytokines in oral epithelium, antimicrobial effect of antibodies, and phagocytic function of neutrophils (PMNs) and macrophages

Question 11

what is the complement system of innate immunity?

Answer 11

induces bacterial lysis in a nonspecific way, promotes chemotaxis (recruits neutrophils and macrophages), promotes opsonization of bacteria, and HELPS ACTIVATE MAST CELLS WHICH INCREASES VASCULAR PERMEABILITY, coats bacteria and makes it more apparent to macrophages and neutrophils (“makes it more tasty”)

Question 12

which cytokines are universal signal of infection that help recruit inflammatory cells

Answer 12

IL-1b and TNF-a

Question 13

which cytokine attracts neutrophils in the early stages of infection (chemotactic activity)

Answer 13

IL-8

Question 14

what do prostaglandins do?

Answer 14

• induce vasodilation and cytokine production

- PGE2 induces production of matrix metalloproteinases by fibroblasts and osteoclasts which damage perio tissues

Question 15

what do matrix metalloproteinases do?

Answer 15

degrade ECM (eg. PMN collagenase degrades major structural protein in gingiva). CONCENTRATIONS ARE HIGHER IN INFLAMED GINGIVA THAN IN HEALTHY GINGIVA

Question 16

what do proteinase inhibitors do?

Answer 16

antagonize inflammation, and inhibit degradation of matrix proteins (eg. Alpha-2 macro globulin: broad spectrum proteinase inhibitor, Alpha -1 antitrypsin: broad spectrum proteinase inhibitor and potent inhibitor of PMN collagenase)

Question 17

what are antimicrobial peptides

Answer 17

• defensins are produced by salivary gland epithelium and inhibit bacterial and fungi
• calprotectin are produced by epithelium, PMNs, monocytes, and macrophages, chelates zine and inhibits bacteria and fungi

Question 18

what is adaptive or acquired immunity

Answer 18

the seance line of defense, with specific responses to bacterial antigens. involves antigen recognition, immune memory, and clonal expansion

Question 19

which last longer, neutrophils, or monocytes and macrophages?

Answer 19

monocytes and macrophages

Question 20

if monocytes and macrophages don’t fix the problem, what’s next

Answer 20

lymphocytes come in and if the chronic inflammation is not resolved, then theres a standoff or systemic infection

Question 21

bacteria colonizes supra gingival and sub gingival environments, but only this environment is aerobic

Answer 21

supra gingival

Question 22

what do TLRs do?

Answer 22

can turn on cytokines and antimicrobial peptides, nitro oxide, and eicosanoids

Question 23

what do secretory IGAs do

Answer 23

protect bacteria from attaching to surface of mucosa

Question 24

what do Von Ebner’s proteins function as

Answer 24

antimicrobial peptides

Question 25

what does LPS (endotoxin) do

Answer 25

complement, PMN, and macrophage activation …b-cell mitogen activity, stimulation of bone resorption, and prostaglandin synthesis, and induction of TNF-a

Question 26

where do we find neutrophils (PMNs)?

Answer 26

deployed from the blood and into infection and inflammatory sites

Question 27

where are macrophages found

Answer 27

in organs and tissues

Question 28

where are mast cells found

Answer 28

throughout the body, especially in CT subjacent to mucosal surfaces