Lecture 6 - T Cell Differentiation Flashcards
Are T cell receptors (TCR) created through V(D)J recombination?
Yes.
Are RAG-1 and RAG-2 used in TCR synthesis?
Yes.
What is CD3 and zeta? Which TCRs are they associated with?
They are signal transduction molecules in the membrane that are associated with ALL TCRs.
Which TCR co-receptor interacts with MHC class II molecules?
CD4+
Which TCR co-receptor interacts with MHC class I molecules?
CD8+
What is the result of CD8+ T cell binding to MHC I + peptide on an infected cell?
Killing of the infected cell.
What is the result of CD4+ T cell binding to MHC II + peptide on an infected cell?
Cytokine synthesis.
What part of the MHC molecules do the CD4 and 8 co-receptors bind to?
The invariant parts of the MHC
Do CD4 and CD8 participate in signal enhancement?
Yes!
Which T-cells bind HIV?
CD4+ T cells
What is the main organ for T cell development?
Thymus
What is DiGeorge syndrome?
Faulty thymus and parathyroid development. Patients don’t have T cell responses - highly immunodeficient.
During T cell development, when do NK cells branch off?
Prior to TCR gene rearrangement - they therefore do not have TCRs.
Do gamma-delta T cells undergo positive and negative selection?
No, they exit the thymus after successful recombination to gamma-delta.
What is a double-positive thymocyte?
After successful rearrangement to alpha-beta, the T cell is CD4+ AND CD8+. This cell is called a double positive and goes on to positive selection.
