T Cell Function-Lecture 10/12/21 Flashcards
5 subsets of helper T cells
- Th1
- Th2
- Th17
- Tfh
- Treg
Signature cytokines of Th1
IFN-gamma
Signature cytokines of Th2
IL-4 and IL-5
Signature cytokine of Th17
IL-17
Signature cytokine of Tfh
IL-21
Signature cytokine of Treg
IL-10, TGF-B
What Th1 acts on
Macrophages, NK cells, CD8 T cells
What Th2 acts on
Eosinophils, basophils, mast cells
What Th17 acts on
Neutrophils and epithelial cells
What Tfh acts on
Naive B cells
Polarized response
In response to a particular pathogen, one type of helper T cell is made more than others
Th1 function
Viral and intracellular bacterial infection
Th2 function
Parasites and allergy
TH17 function
Fungi and extra cellular bacteria
IL-12
Cytokine that is released when DC recognizes a virus, stimulates Th1
IL-4
Released by DC to stimulate helper T cell to be Th2 (also released by Th20
IL-23
Released by DC in response to fungi that tells helper T to be Th-17
CD40 ligand
Expressed by Tfh cell, tells second messenger to activate B cell
What prompts class switching
Cytokines released by Tfh cell
Thymus independent antigens
Some polysaccharide ags (like LPS) B cell activated without T cell help, very little class switching or SHM
Signals for CD8 T cells
1st peptide MHC interaction
2nd cytokines from effector CD4+ T cells or CD28 B7 interaction
Two methods that killer T cells kill
- Through the release of performing and granzymes
2. FAS/FASL
CAR-T cell components
Antigen receptor, T cell signaling unit (CD3)