T Cells 5 Flashcards
what cytokines are involved in TH17 signal 3?
- THF-beta
- IL-6
- IL-23
what are the effector cytokines of TH17?
- IL-17
- IL-22
what is the master transcriptional regulator of TH17?
RORgammaT
how did the discovery of TH17 change the study of immunology?
originally believed TH1 and TH2 were the only T cells
what are the 2 general roles of TH17 cells?
- enhance neutrophil response
- mucosal immunity
what 2 types of pathogen do TH17 cells respond to?
- extracellular bacteria
- fungi
are TH17 cells involved in pro or anti-inflammatory response?
pro-inflammatory
what type of disease are TH17 cells involved in?
autoimmune disorders
describe the steps of TH17 activation
- signal 3: IL-6, IL-23, TGF-beta
- TF: STAT3 activated
- master transcriptional activator: RORgammaT gene is activated
- IL-17 and IL-22 secreted
IL-17 and IL-22 stimulate the secretion of what molecules? (3)
- Cytokines
- Chemokines
- Antimicrobial peptides
what type of autoimmune diseases and allergies are TH17 responses involved in? (5)
- Psoriasis
- Inflammatory bowel disease
- Asthma
- Rheumatoid arthritis
- MS
what type of cytokine is IL-17?
pro-inflammatory
what is the TH17 response called?
Type 3 Response
what are the 5 effector functions of TH17?
- induce production of antimicrobial peptides
- increase epithelial turnover
- induce other cells to produce G-CSF
- induce other cells to produce chemokines
- attract more TH17 cells
how does TH17 induce production of antimicrobial peptides?
IL-17 and IL-22 bind receptors and can induce epithelial cells to produce antimicrobial peptides
what do the antimicrobial peptides produced from TH17 do?
contributes to killing/slowing replication of bacteria
how does TH17 increase epithelial turnover?
IL-22 increases division and shedding of epithelial growth
what is the result of epithelial turnover by TH17? why?
Reduced bacterial growth
because bacteria adhere to epithelium to be able to colonize –> if increased turnover, hard for bacteria to grow and colonize