T-cell lymph Flashcards
What are the most immature T-cells
Double negative
From bone marrow going to thymus
What is the most mature T-cell
Single positive (CD4+ or CD8+)
What is a T-cell receptor made of
alpha and beta chain or gamma delta chain
What is the T-cell beta chain equal to
Heavy chain of B-cell
Is there somatic hypermutation or class switching in a T-cell
NO
What part of T-cell rearranges first
Delta
Does rearrangement of TCR use the same enzymes as BCR
yes
What happens first with expression of TCR
Gamma, delta, beta rearranged simultaneously
If gamma delta arrangement is unsuccessful, it becomes alpha beta
Does TCR have allelic exlusion
yes, but not as tightly enforced
Where are thymocytes educated at
Thymus
What happens during T-cell positive selection
TCR interacts with self peptide: self MHC=survival
Changes from double positive to CD4+ or CD8+
Ensures that TCR can recognize the Ag presented by MHC
What happens during TCR negative selection
TCR interacts too strongly with self=DEATH
Ensures against autoimmunity
What happens to T-cells in second lymph tissues
Become Naive cells or memory cells
Long term memory formed
(come back to finish this flashcard) Compare contrast TCR vs BCR
TCR Diff: Ag must be presented by MHC, positive and negative selection, never secreted
What do negative and positive refer to with T-cell
CD4 and CD8
