T cells Flashcards
What do Th1 cells secrete and what is their function?
secrete: IFN-gamma
function: activate macrophages and CTL to kill phagocytosed microbes
What do Th2 cells secrete and what is their function?
secrete: IL-4, 5, 6, 10, 13
function: activate eosinophils, promote IgE production for parasite defense
What do Th17 cells secrete and what is their function?
secrete: IL-17, 21, 22
function: immunity against extracellular microbes, induce neutrophilic inflammation
What do Treg cells secrete and what is their function?
secrete: TGF-8, IL10, 35
function: maintain tolerance to self-antigens (prevent autoimmunity)
What induces/inhibits Th1 cells?
induce: IFN-gamma, IL-12
inhibit: IL-4, 10 (from Th2 cell)
What induces/inhibits Th2 cells?
induce: IL-4, 10
inhibit: IFN-gamma (from Th1 cell)
What induces/inhibits Th17 cells?
induce: TGF-beta, IL-1, 6
inhibit: IFN-gamma, IL-4
What induces/inhibits Treg cells?
induce: TGF-beta, IL2
inhibit: IL-6
Describe the interaction of macrophages and T cells.
Th1 secrete IFN-gamma which enhance monocyte/macrophage ability to kill microbes they ingest, mediated by interaction of CD40L (T cells) with CD40 (macrophages)
Describe the action of CTLs.
Induce apoptosis in virus-infected, neoplastic, donor graft cells
release cytotoxic granules
Have CD8 which binds to MHC 1 of virus-infected cells
What surface markers are expressed by TREGs?
CD3, 4, 25 and FOXP3
What is the role of TREGs?
suppress CD4 and CD8 T-cell effector functions (maintain specific immune tolerance)
produce inflammatory cytokines when activated
Describe IPEX syndrome
Immune dysregulation, Polyendocrinopathy, Enteropathy X-linked
Due to FOXP3 genetic deficiency on TREGs
Symptoms: enteropathy, endocrinopathy, nail dystrophy, dermatitis, autoimmune dermatologic conditions
associated with diabetes in male infants
