Immunity: Chapter 05 Activation and Effector Actions of T Cells

Table of Contents

1. 5-1 Antigen Recognition by T Cells: Structure of the Receptor
2. 5-2 Antigen Recognition by T Cells: TCR Specificity and Coreceptors
3. 5-3 Signaling from the T Cell Receptor
4. 5-4 Regulation of TCR Signaling
5. 5-5 T Cell Signaling to the Nucleus and the Role of CD28
6. 5-6 Activation of Naïve T Cells in Secondary Lymphoid Tissue
7. 5-7 Clonal Expansion of Naïve T Cells in Secondary Lymphoid Tissue
8. 5-8 Costimulatory Signals in T Cell Proliferation and Survival
9. 5-9 Effector T Cell Differentiation
10. 5-10 The Polarization of TH1 and TH2 Cells
11. 5-11 The Functions of TH1 Cells
12. 5-12 The Functions of TH2 Cells
13. 5-13 The Functions of TFH Cells, TH17 Cells and Induced TREG Cells
14. 5-14 Effector Functions of CD8 T Cells
15. 5-15 T Cell Homeostasis and the Termination of Immune Responses
16. 5-16 T Cell Memory

5-2 Antigen Recognition by T Cells: TCR Specificity and Coreceptors

Work through the following questions, checking all the correct answers. For each question there may be more than one correct answer.

1

The diversity of the T cell antigen receptor repertoire in any given individual is limited by: a) the elimination of self-reactive T cells in the thymus. b) the number of different receptors that can be generated from the different gene segments in the genome. c) survival of T cells that weakly recognize self peptide plus self MHC. d) selective survival of T cells that recognize antigens. CorrectWrong: a, c and d are correct.Your answer has been saved.

2

Which of the following statements are true? a) The antigen receptors of T cells recognize variation only in the peptide bound to the MHC molecule and not in the MHC molecule itself. b) The flexibility of the hypervariable loops of the TCR V region increases the versatility of the receptor in binding a wide range of peptide-MHC complexes. c) In peptide-MHC binding, most contacts with the peptide are made by CDR1 and CDR3 of the TCR. d) In some cases, binding interactions of intermediate strength between a TCR and a peptide-MHC complex can inhibit T cell responses to peptide-MHC complexes that bind with higher affinity to the same TCR. e) CD8 recognizes a non-polymorphic site on the MHC class I molecule. f) The γδ receptors of T cells have invariant binding sites for antigen g) The γδ receptors of T cells do not require coreceptors for signaling. h) γδ T cell receptors can recognize non-classical MHC class I molecules. CorrectWrong: b, c, d, e, g and h are true.Your answer has been saved.

3

Which of the following are properties of the CD8 and CD4 coreceptors expressed on T cells? a) Binding to polymorphic portions of MHC molecules. b) Differential recognition of MHC class I and MHC class II molecules. c) Binding to peptide bound to MHC molecules. d) contributing to signaling on antigen binding. CorrectWrong: b and d are correct.Your answer has been saved.