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11.
Cellular response:
a.
Recall the effector cells and state their function.
Helper T cells (CD4)
a.
Activate B and cytotoxic T cells
b.
Induce B and T cell proliferation
c.
Activate macrophages, stimulate inflammation
Cytotoxic T cells (CD8)
a.
Circulate blood and lymph
b.
Class I MHC antigens
c.
Kills infected body cells via perforins and granzymes
d.
Triggers cell apoptosis
Regulatory T cells
a.
Dampen immune response by secreting inhibitory chemicals
b.
Explain the difference between a CD4 and a CD 8 T cell.
CD4 becomes helper/regulatory T cells and CD8 becomes cytotoxic T
cells
They become active when they come into contact with a pathogen
c.
Recall that T cells require the assistance of APCs in their clonal
selection process.
Contrast Class I and Class II MHC and their
respective roles in T cell activation.


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Class I (mostly all body cells)- display a lot of endongeous(but not
foreign ) antigens; activates CD8 cells. Directly getting activation of
CD8
Class II(found on APCs)- displays a lot of exogenous antigens; activate
CD4/helper T cells. Indirectly getting activation.
d.
Outline the mechanism of clonal selection of a T cell (including the
role of cytokines).
Process
a.
Antigen binding
b.
Co-stimulation (molecule on the surface of APC. A way to have
a safeguard against self-cell attack)
c.
Proliferation of activated T cell (effector and memory cells)
Cytokines (assist with differentiation)
a.
Enhance macrophage activity
b.
Enhance inflammation
c.
Activated T cell proliferation
d.
Describe the central role of helper T-lymphocytes in both the humoral
and cellular adaptive immune responses.


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e.
Describe how cytotoxic T-lymphocytes destroy pathogens via
perforins and granzymes.
1.
Tc identifies foreign antigens on MHC I proteins and
binds tightly to target cell.
2.
Tc releases performis and granzymes
3.
Performis molecules pores into membrane
4.
Granzymes enter the via pores and trigger apoptosis
5.
Do it again!