What is the definition of Naive T-cell?
Never seen antigen
What is the function of Th1 cells?
provide immunity for exogenous microbes in phagosomes in phagosomes
What is the function of CTLs (Tc)?
provide immunity for endogenous microbes within the cytoplasm
What is the function of Th2 cells?
provide immunity against exogenous helminths and allergies
Overall, do T-cells attack intracellular or extracellular microbes?
What MHC molecules are required to present antigen to Th and Tc cells?
Why are APCs effective at activating Naive T-cells?
- They constituitively produce B7 and MHC
- ** Macrophages must be activated by IFN-gamma to produce these, so they work best after activation of T-cells
What is Anergy?
- When the second signal, B7 to CD28, is not available
- T-cell goes through apoptosis
After the second step of T-cell activation, what motifs are produced in the T-cell nucleus?
What is the role of the three motifs produced from active T-cells?
How can you use T-cells to attack a tumor?
- Remove TIL (tumor infiltrating lymphocytes) from tumor
- Add IL-12 exogenously
- reintroduce Active T-cells into tumor
What is the function of cyclosporin and Tacrolimus?
- Inhibit T-cell activation
- * They bind calcineurin which will bind NFAT and inhibit production of IL-12
What are the three effector T-cells and their functions?
- Th1: cell-mediated immunity
- Th2: humoral immunity (activate B-cells)
- Th17: inflammation and microbial defense
What are the two Autocrines in T-cell activation/proliferation?
IL-2 and IL-4
What are five cells that Th1 cells activate?
- NK cells
- B-cells for opsonization (IgG)
What Cytokines are produced from Th2 cells?
What are the roles of Th2 cells?
- Humoral immunity
- Activate non-opsonizing B-cells
- Helminth/allergin affects from Mast Cells / Eiosinophils
- inhibit macrophages (IL-4, IL-13)
Why is an abundance of Th2 cells dangeroud?
IL-10 inhibits macrophages
What are the two pathways of CTL attack?
- 1) Degranulation: insert perforin to create a pore for granzymes
- 2) Fas-FasL: all nucleated cells produce Fas. When a CTL recognizes the MHCI antigen, then FasL will bind to Fas and cause degranulation