T cell development, activation, and function

Question 1

Know the structure and function of the T Cell receptor be able to distinguish TCR from BCR

Answer 1

T cell receptor (TCR)- responsible for Ag recognition (Uses APC) (Used with MHC)
Four different chains…Alpha/beta (90% of T cells in our body; reside in secondary lymphoid tissue) always associate with each other and gamma/delta (found in gut) are together
We’ll talk mostly about alpha/beta. Instead of being a Y shape like B cell receptor, alpha is a straight line linked to a straight beta (II). each one has one variable and one constant region.
The variable region HAS to recognize an Ag AND MHC to be activated

Question 2

Understand the function and importance of costimulatory factors necessary to T cell activation

Answer 2

The variable region HAS to recognize an Ag AND MHC to be activated

Question 3

Compare/Contrast T cell and B cell activation

Answer 3

Both CD4/8 will recognize the MHC complex on the surface, activate a Lck (lick) molecule inside the cell and that will go phosphorylate a CD3 complex. CD3 activation leads to a cascade that activates the entire cell
TCR also undergoes V(D)J recombination like B cells and has to come in contact with a MHC on an Ag cell

Question 4

Know the differentiation factors and effector functions of CD4 and CD8 T cells

Answer 4

CD8- are cytotoxic T cells and recognizes MHC1
CD4- are helper T cells and recognizes MHC2
THE WHOLE FUNCTION OF CD4 AND CD8 IS TO BEGIN SIGNAL TRANSDUCTION that activates the cell