3. Oral Defense Mechanisms Flashcards
- Oral Immunity
- What are four examples of innate immunity processes in the mouth?
- Saliva
- Thick, continually recycling epithelium
- Gingival junctional epithelium
- Competitive normal flora
- Saliva
- What are the five properties of saliva that make it an innate immunity process?
- Constant H2O flush
- Dissolves food
- Buffers (acids)
- Contains anti-bacterial molecules (sIgA)
- Provides protective oral “coating”
- Thick, continually recycling epithelium
- What three properties make this an innate immunity process?
A. Describe its keratin layer
B. Tight or loose junctions
C. Permeable or impermeable
A. Tough keratin layer with high lipid content
B. Tight junctions
C. Impermeable
- Gingival junctional epithelium
- What three properties make this an innate immunity process?
A. Describe its keratin layer
B. Tight or loose junctions
C. Permeable or impermeable
- Gingival junctional epithelium
A. Non-keratinized with low lipid content
B. Loose junctions
C. Allows plasma fluid and inflammatory cells access to mouth
- Histology of oral gingival junctional epithelium
- Describe the keratinocytes of this epithelial layer
A. Highly or poorly differentiated?
B. High or low production of keratin and hydrophobic granular materials
C. Tightly or loosely linked to each other
A. Poorly differentiated
B. Low production of keratin and hydrophobic granular materials
C. Loosely linked to each other
- Junctional epithelial cells display HLA class II and therefore can present extracellular _______ peptides, thereby activating _________ cells.
- Antigenic
- T helper cells
(HLA : Human leukocyte antigens)
- When junctional epithelial cells are stimulated by certain microbial products they release what substances?
They release chemokine IL-8 and numerous other cytokines and chemokines.
- The release of chemokine IL-8, other cytokines, and other chemokines can activate and stimulate what structures and cells?
Activates and stimulates:
- Local capillaries
- Mast cells
- PMN’s (they are chemotactic/attractants for neutrophils)
- Why do we have a non-keratinized, non-hydrophobic, “leaky” surface at the junctional epithelium around each tooth?
This allows capillary plasma defense molecules (like IgG) and PMNs easy access to the mouth.
They can respond to any bacterial infection (like plaque) and induce a localized inflammatory reaction. The inflammatory reaction will cause local edema and PMNs to go into and through the junctional epithelium.
- What is the name for the fluid found in the junctional epithelium (in the sulcus)?
- What anti-microbial molecules are found here?
Crevicular fluid (aka Sulcular fluid)
PMNs and IgG
- Beyond the crevicular fluid is saliva. What are examples of the anti-bacterial molecules that saliva contain?
- Ag-specific sIgA
2. Numerous “generic”, non-Ag specific, antimicrobial agents (like lysozyme)
- In addition to possessing anti-bacterial molecules, how does saliva combat toxins and acids produced by oral microorganisms?
It buffers, dilutes, and washes away toxins and acids produced by oral microorganisms
- Where are PMNs produced?
Where do PMNs mature?
In the blood, how long is their half-life?
In tissue, how long is their half-life?
Produce and mature in the bone marrow
Blood: 6 hours
Tissue (most PMNs): 1-2 days
- Why does the body keep 5-10x the # of blood & tissue PMNs in storage in bone marrow?
These PMNs can be released if the body needs a quick boost in PMNs at some infection/inflammation site.
- Once at a inflammation site, PMNs use ______ to bind and engulf opsonized pathogens.
Surface receptors (FcR, C3b-R, etc)
