L18 Flashcards
What effector function do CD8s have?
kill virus-infected cells
Viruses e.g. flu, rabies. Some intracellular bacteria too.
What effector function do CD4s Th1 have?
Activated infected macrophages and provide help for B cells for ab production. Help with microbes that persist in macrophage vesicles and extracellular bacteria
What effector function do CD4 Th2 have?
Provide help to B cells for ab production especially switching to IgE. Helpful in Helminth parasites
What effector function do CD4 Th17 have?
Enhanced neutrophil response and promote barrier integrity (skin, intestine). For Klebsiella pneumoniae, fungi C.albicans.
What effector function do CD4 TFH have?
B cell help isotype switching and ab production, help with all types of pathogen
What effector function do CD4 Tregs have?
supress T cell responses
what cytokines stimulate Th1 differentiation and what cytokines do Th1 CD4 T cells make themselves
If you stimulate naive T cell in presence of IL-12 it will differentiate into Th1.
All Th1s make IFNγ. IFNγ actually also works autocine loop to reinforce itself to differentiate. IFNγ acts on macrophages activated them and infected cells, important for vacuole restricted bacteria
What is the result of macrophage activation by Th1s?
IFNγ stimulation leads to more MHC presented on surface due to increase in expression, increases co-stimulatory molecule expression, increases production of free radicals to eliminate bacteria and helps with phagolysosome TNFα production
What cytokines drive TH2 CD4 differentiation and what do they produce?
IL-4 drives Th2 differentiation. Itself also makes IL-4 which reinforces its own differentiation and other naives into Th2. Th2 are for parasites and allergies (inappropr response). IL-4 promotes B cells to class switch. It also makes IL-5, 13.
What cytokines drive Th17 CD4 differentiation and what do they produce?
Phenotype occurs when there’s lots of inflamm cytokines e.g. IL-1b, IL-6, IL-21 and maintained by IL-23 plus TGFβ. They secrete IL-17, good at recruiting neutrophils and controlling epithelial barrier function. Useful for fungal infections.
What cytokines drive Tfh CD4 differentiation and what do they produce?
Driven by IL-21They remain in lymph node because they help B cells. Activated to switch on CXCR5 so it migrates to B cell zone. CXCR5 is what B cells use to localise to B cell zone.
What cytokines drive Tregs CD4 differentiation and what do they produce?
Derived from 2 sources:
Thymic T cell that bound to self antigen/autoreactive and turn into T regs to control autoreactive responses.
Peripheral derived Treg: under certain cytokines they can differentiate into naive: retinoic acid and TGFβ
FOXP3 TF
