Pathogenesis - Lecture II Flashcards
Tell me the critical pathway model of pathogenesis.
Normal flora->Pathogenic flora
If immune response (neutrophil clearance) occurs, then gingivitis and limited disease. If NOT, bacterial penetration.
Bacterial penetration
- Can lead to systemic exposure
- Or initial periodontitis
Monocyte/lymphocyte axis
Cytokines and inflammatory mediators
Inflammation and tissue destruction
Pocketing and bone loss
RER produces what?
Proteins and antibodies
Antibodies expressed on the surface of bacteria are called what?
Phenotype
PMNs recognize the Fc fragment
What is the most common antibody?
IgG - 80-85% of total serum immunoglobulin
Tell me about IgG.
Monomer
Attach to phagocytes
Complement fixation
-Opsonization
-Agglutination
*Can cross placenta
21 day half life
Tell me about IgM
Pentamer (Looks like 5 IgGs)
5-10% of serum immunoglobulin
10 day half life
Complement fixation
Can combat capsules
Agglutination, complement, leads to inflammation
Tell me about IgA.
Looks like a dimmer of IgG
10% of total serum
6 day half life
Secreted in saliva, milk, mucus, and other secretions
Protection of mucus membranes by preventing attachment of organisms
Tell me about IgD.
Looks like IgG
<1% of total serum
3 day half life
Antigen receptor on B lymphocytes
Facilitates development and maturation of the antibody response
Tell me about IgE.
Looks like a taller IgG.
<0.01% of total serum
2 day half life
Attaches to mast cells and basophils
-Antigen reacts with cell-bound IgE to release granules contents
Involved in many allergic reactions
*Helps expel parasites
What holds the long chains together?
Disulfide bonds
*Some bacteria release enzymes to break disulfide bonds
T/F - Light chains are highly variable, and the heavy chains are heavily conserved.
TRUE
T/F - The Fab region binds the antigen.
TRUE
B cells come from where?
Bone marrow
Also, nodes and bursae
How does the primary response differ from the secondary response?
Primary - High IgG and High-ish IgM
Secondary - 20x’s higher IgG and about the same about of IgM
What is an antibody response that is beneficial for bacteria?
Polyclonal response
- Virulence factor for bacteria turns on a lot of antibodies
- This creates a needle in the haystack situation
What are 3 beneficial antibody related responses for the host?
Local response
Systemic response
Monoclonal response
The macrophage comes from what stem cell, then what cell, then becomes a macrophage?
Myeloid stem cell
Monocyte
T/F - Macrophages are mobile and have LONG half-lives.
TRUE
T/F - LPS stimulates macrophages.
TRUE
Macrophages, dendritic cells, and plasma cells all express MHC class _____.
II
IL-1 produced by __________ plays an important role in tissue ___________ associated with periodontal disease.
Macrophages
Breakdown
Most people are what type of genotype?
Genotype positive - Hypersensitive
What host based risk factors cause monocyte dysregulation?
Diabetes
Smoking
*Increase inflammation, MMP expression, and concomitant tissue destruction
CD8 binds what MHC?
MHC I
T/F - CD8 CELLS ARE CYTOTOXIC.
SO DANG TRUE SON
CD4 binds what class?
MHC II
*Helper cells
HIV affects which T cell?
CD4
*Decreases its number and causes an early death
What removes NK cells?
CD4
T/F - Necrotizing ulcerative periodontitis (NUP), Necrotizing ulcerative gingivitis (NUG), and HIV-associated periodontitis (HIV-P) all describe the same thing.
TRUE