Roles of Specific Effector T Cells

What are the three groups of T cells

cytotoxic T cells, helper T cells, regulatory T cells

What do helper T cells do

- play central role in adaptive immunity

-produce cytokines

- cytokines stimulate b-cells to divide into plasma and memory cells

- activate killer t-cells

How do helper T cells help in humoral immunity

1) Th cells binds with the self-no self complexes of a B cell that has encountered its antigen and is displaying it on its MHC II surface

2) Th cell releases interleukins as costimulatory signals to complete B cell Activation

How do T helper cells help in cellular immunity

1) Th cell binds to dendritic cells

2) Th cell stimulates dendritic cell to express co-stimulatory molecules

3) Dendritic cell can now activate CD8 cell with the help of interleukin 2 secreted by Th cells

How are B cells activated

B cell is activated when it encounters an antigen that matches its B cell receptors and receives cytokines from helper T cells.

How are CD8 cells activated

activated by CD4 aka helper t cells

(CD8 are t killer cells)

What are cytotoxic T cells

T cells that can directly attack and kill other cells. They roam the body. Circulating in and out of the blood and lymph and through the lymphoid organs in search of body cells displaying antigens that the Tc cells recognize

How do cytotoxic T cells kill

1) secretion of perforins and granzymes

2) binding to a specific membrane receptor on the target cell that stimulates the target cell to undergo apoptosis

What are regulatory T cells

type of T cell that helps to prevent autoimmunity