8. Regulation of the Immune Response Flashcards
Surface markers of T reg. cells (5)
CD25, CD103, Foxp3, GITR, (glucocorticoid-induced TNF receptor)
Cytokine expression/secretion of Treg cells
IL-10, IFN-gamma, TGF-beta
Can Tregs prevent initial T activation?
No, it can inhibit sustained response (prevent chronic and potentially damaging responses)
Th1 releases …. that inhibits Th2
IFN-gamma
Th2 releases … that inhibits Th1
IL-4, IL-10, TGF-beta
Telomers provide … and protect …
Stabilization, chromosomal ends from damage (regulate cell replication)
At every cell division telomers shorten by
50-100 bp
What is cellular senescence?
A cell entering cell arrest (eg. when telomer becomes too short -> chromosome unstable -> DNA damage can occur)
B cell negative costimulation
- Regulation by antibody
- Receptor cross-linking -> Ag/Ab complexes binding to Fc receptors send inhibitory signal to B cells
B cell positive costimulation
- Regulation by antibody (and complement)
- Ab/Ag immune complex bind C3b -> activation of B-cells
Effector molecules of Treg cells
TGF-beta1, CTLA-4, IL-10
Idiotype
The sum of idiotypes, variable determinants in a given Ab molecule or TCR
Neuroendocrine modulation
Release of steroids, catecholamines, encephalins, endorphins
Neuroendocrine release in vivo leads to
Usually immunsuppression during stress
Stimulants of adrenal corticosteroid production
IL-1 and IL-6
