Final exam Flashcards
health dynamics and disease imbalance with respect to cytokine expression?
In health there are the same cytokines expressed like in disease. Cytokines and chemokines play key roles in tissue remodeling. When there is cytokine increase there is an imbalance.
What is a role of cytokines other than role during the infection?
Cytokines can affect morphology, migration and differentiation. Ex: self renewing tissues like gingival epithelium may require IL-8.
What is a neutrophil and what is/are its functions?
They engulf and destroy bacteria and other pathogens. Most abundant WBC. Fastest response of all WBC. Neutrophils circulate in the body and move to the site of the infection to fight pathogens.
Direct action against bacteria:
1) release lysozyme to lyse bacterial CW
2) Release defensins that act as antibiotics and poke holes in bacterial CW
3) Release strong oxidants
Active in the initial stages of the infections. Short half life. Part of the innate system.
What is gingival crevicular fluid (GCF) and what is its role in health? e.g. what does it do for commensal bacteria and what does it due to potential invaders?
GCF is at the gingival margin, serum flows from the inside of the gingiva into the mouth.
The flow of this fluid removes foreign microbes that have not adhered yet. For the resident population GCF is a source of nutrients. Resident cells have special enzymes that break down these proteins to provide them with nutrients for growth.
What is GCF composed of?
Composed of Leukocytes, complement, IgG, IgM, IgA, lysozyme and peroxidase
Is GCF only present in disease?
NO. GCF is an inflammatory exudate. Its presence is clinically normal. The amount of GCF is sometimes proportional to the amount of inflammation.
What are some of the ways you can increase GCF production? (Do any seem surprising?) What is it not increased by?
NOT increased by trauma. Increased by masticatio of coarse foods, toothbrushing and gingival massage, ovulation, hormonal changes, hormonal contraceptives, and smoking
What is the major host response factor in GCF?
Macrophage inhibition factor
What is the pattern recognition hypothesis?
It provides a conceptual framework to understand host responses to LPS.
What are the PRR Ligands?
They are shared by a large group of pathogens, conserved and essential structures (Attempt to modify results in death of microorganisms or loss of virulence) and they are distinct from self antigens
What is the role of lipopolysaccharide (LPS), lipoteichoic acid (LTA), and Peptidoglycan in pattern recognition?
They all are recognized by the innate host response system.
G+ cell envelope has teichoic acid, which provides flexibility to the CW.
G- cell envelope has LPS (lipopolysaccharide) which establishes permeability barrier.
LPS is an endotoxin that has a conserved part lipid A. LPs- lipid a is a small component of LPs
peptidoglycan - both G+ and G- have it
Know which Gram + and Gram – have LPS, LTA, and Peptidoglycan?
LPS: G-
LTA: G+
Peptidoglycan: both G- and G+ but G+ has a thicker one
Know which Toll-like receptor recognizes LPS, LTA, and Peptidoglycan ?
TLR-2: peptidoglycan, LTA
TLR-4: E. coli and P. gingivalis LPS
Know the difference between germ free mice and conventional (healthy) mice and how it affects the mucus layer. How does this impact health in relation to the microbiome?
GF mice don’t have any bacteria at all
conventional (healthy) mice have commensal bacteria
GF in intestine dont have any bacteria → mucus is thicker and vascular. GF mice have more alveolar bone, since no bacteria → no bone turnover → more bone accumulation
What chemokine is essential for neutrophil migration into periodontal tissue?
IL-8
