Quiz 5 Flashcards
What are the names of the structures on bacterial cells that antibodies bind to?
Epitopes (antigenic determinants)
IgG:
80% of total immunoglobins, agglutination, opsonization, complement fixation
IgM:
5%, first antibody produced during immune response, agglutination, opsonization, complement fixation
IgA:
10%, secreted into saliva, milk, secretory one, protection of mucous membranes
IgD:
<1%, antigen receptor on B lymphocytes, facilitates development of the antibody response
IgE:
<0.01%, attach to mast cells and basophils, involved in allergic reactions, helps expel parasites
Which antibody has a greater response during the secondary response of antigen injection?
IgG
What is the most important cell in the breakdown of collagen?
Fibroblasts
What happens when LPS binds to a monocyte/macrophage/
It binds to the CD14 receptor, resulting in production of PGE2, IL-1b, TNF-a, and MMP’s, and then IL-1b and TNF-a go on and activate resident fibroblasts, which results in production of additional PGE2, and MMP’s which go on and resorb alveolar bone and destroy the connective tissue, respectively.
What are the two types of cells that macrophages will influence the response of?
Fibroblasts and Osteoblasts. Also IL-1.
Which type of people have more bleeding on probing, genotype positive or negative, and what is it that they produce more of?
Genotype positive, they produce more IL-1, which stimulates more fibroblasts and osteoblasts, and can cause more damage, hence the bleeding. 47% to 9%.
What do activated T cells produce, and what does it cause?
They produce IL-2, and it causes proliferation of the T cells.
What is the difference between Th1 and Th2 helper cells?
Th1 go off and activate macrophages to kill intracellular organisms. Th2 helper cells and B cells are in charge of making memory cells, and making antibodies. So these Th2 must be in charge of helping the B cells to all of this.
What is the definition of a cytokine?
Low molecular weight proteins that mediate interactions among lymphocytes, inflammatory cells and other cellular elements in connective tissue.
IL-1 (alpha and beta):
1) Pleiomorphic
2) Includes osteoclast and lymphocyte activities
3) CD4 activation
4) B-cell maturation
5) increases NK cell activity, fibroblast procollagen, PGE2 and bone resorption
6) secreted by monocytes, macrophages, B-cells, fibroblasts, PMNs, epithelial cells and other stimulated cells
IL-2 (alpha and beta):
1) general role in immune response
2) stimulates macrophages
3) modulates and induces NK function and proliferation
4) secreted by CD4 and NK cells
5) Increases during periodontitis
IL-3:
1) supports growth/differentiation of hematopoietic stem cells
2) stimulates mast cell growth and histamine secretion
3) secreted by activated CD4 and NK cells
IL-4:
1) B-cell activation, proliferation and differentiation
2) T-cell growth, macrophage function, growth of mast cells
3) secreted by CD4 cells
4) B-cell IgE synthesis
5) Increases during periodontitis
IL-5:
1) Induces B-cell proliferation
2) Enhances IgA production
3) Secreted by CD4 cells
IL-6:
1) Stimulates plasma cell production
2) Along with IL-1, activates CD4 cells
3) secreted by CD4, macrophages, monocytes, fibroblasts and endothelial cells
4) Increases in sites of gingival inflammation
5) Role in bone resorption
IL-7:
1) induces T-cell proliferation by expressing IL-2 and IL-2 receptors
2) secreted by bone marrow cells
IL-8:
1) increases PMN adherence to endothelial cells
2) secreted by macrophages in response to IL-1, TNFalpha
3) Present high levels in perio lesions assoc with JE and macrophages
4) Stimulates PMN MMP activity
IL-9:
1) induces proliferation if CD4 cells in absence of antigen/ antigen presenting cell
2) promotes growth of mast cells
3) secreted by CD4 cells
IL-10:
1) inhibits the antigen-presenting capacity of monocytes
2) secreted by CD4 cells
IFN’s (alpha, beta, gamma):
1) glycoproteins produced by leukocytes, fibroblasts, T-lymphocytes respectively
2) antiviral activity
3) enhance macrophage activity (gamma), T-cell activity, NK-cell activity
4) plays a role in bone resorption, by inhibiting proliferation and differentiation of progenitors of osteoblasts
TNF (alpha and beta):
1) produced by macrophages and CD4 cells respectively
2) cause necrosis of some tumors
3) TNF alpha produced after stimulation
of macrophages by LPS
4) TNF beta (lymphotoxin)
5) TNF alpha and beta can activate osteoclasts leading to bone resorption
6) alpha increases PMN adherence to endothelial cells
7) alpha increases PMN phagocytosis and chemotaxis
8) effect on PMN and macrophages play a role in vascular changes seen in perio dx
9) TNF beta cytotoxic for fibroblasts
10) plaque antigens favor generation of TNF beta cells and/ or direct lymphotoxicity leading to tissue damage seen in periodontal disease
What are the main 5 characteristics of established gingivitis?
1) Microbial plaque that is better organized and more gram-negative enters sulcus
2) Small gingival pocket with pocket epithelium forms
3) More venules become activated, enhanced expression IL-8 , ICAM-1, E-selectin, enhanced PMN migration
4) Enlarging infiltrate with B and T cells, plasma cells, macrophages
5) PMNs are prominent
What are the 5 major mediators of the events occurring in the proinflammatory/destructive phase of periodontitis?
1) IL-1B
2) TNF-alpha
3) IFN-gamma
4) PGE-2
5) MMPs
- These are all HIGH in disease and LOW in good health.
What are the 5 major mediators of the events occurring in the anti-inflammatory/protective phase of periodontitis?
1) TGF-beta
2) IL-1ra (receptor antagonist)
3) IL-10
4) IL-4
5) TIMPs (Tissue inhibitors of matrix metalloproteinases)
- These are all LOW in disease and HIGH in good health.
