T-Cell Receptor
Also written as TCR.
TSST-1 is a superantigen — it cross-links MHC class II and T-cell receptor outside the normal antigen groove, causing massive nonspecific T-cell activation and cytokine storm (fever, rash, hypotension, multi-organ dysfunction).
What our notes say
- TSST-1 is a superantigen — it cross-links MHC class II and T-cell receptor outside the normal antigen groove, causing massive nonspecific T-cell activation and cytokine storm (fever, rash, hypotension, multi-organ dysfunction). (Medical Bacteriology MCQs: ETEC, Pseudomonas, Salmonella & More)
- The T-cell receptor (TCR) is a crucial molecule on the surface of T cells, responsible for recognizing specific antigens. (Cellular Immunology Short Answer Questions)
- Rearrangement of T cell receptor genes takes place as they exit the thymic medulla (Physio Y1 EOY 2021 — Past Paper Questions & Answers)
- Pre-T ALL: diverse chromosomal aberrations including T cell receptor locus translocations (White Cell Disorders — Must-Know Notes)
- CD8+ T cells (cytotoxic T lymphocytes) recognize these foreign peptides presented on MHC Class I molecules through their T cell receptors. (Cellular Immunology MCQs)
- This branch of immunity relies on highly specific receptors, namely T-cell receptors (TCRs) and B-cell receptors (BCRs), and its effectiveness improves with repeated exposure to an antigen. (Cellular Immunology Short Answer Questions)
Study material on T-Cell Receptor
- Cellular Immunology Short Answer Questions
- Immunology Quiz
- Weekly Year 2: Cellular Immunology Exam - March 27, 2026 (Section A: MCQs)
- Comprehensive Immunology Quiz
- Weekly Year 2: Cellular Immunology Exam - May 1, 2026 (Section A: MCQs)
- Weekly Year 2: Cellular Immunology Exam - June 12, 2026 (Sections B & C)
- Weekly Year 2: Cellular Immunology Exam - June 12, 2026 (Section A: MCQs)
Practice questions on T-Cell Receptor
Which of the following is a transmembrane glycoprotein that serves as a co-receptor for the T cell receptor (TCR), and is also known as a cytotoxic T cell (CTL)? Options
- Cluster of differentiation 4 (CD4+)
- CD8+ T cells
- Plasma cells (activated B cells)
- Activated T cells
- Natural killer cells
Answer: B. CD8+ T cells are cytotoxic T lymphocytes (CTLs) that express the CD8 co-receptor, which binds to MHC class I molecules. These cells are responsible for killing infected or abnormal cells. ---
The biochemical structure of the T-cell receptor (TCR) of the αβ type (95% of human TCRs) is comparable to a immunoglobulin fragment, having very short cytoplasmic tails. Options
- Secreted; Fab
- Secreted; Fc
- TCRs
- Membrane-bound; Fc
- None of the above
Answer: C. TCRs are membrane-bound receptors structurally similar to the Fab portion of antibodies, containing variable regions for antigen binding but with very short cytoplasmic tails. ---
Which of the following best describes the location of the delta (δ)-chain locus in human T-cell receptors? Options
- Chromosome 7
- Chromosome 7 within the alpha (α)-locus
- Chromosome 14
- Chromosome 14 within the beta (β)-locus
- Chromosome 14 within the alpha (α)-locus
Answer: A. The δ-chain genes are located within the α-chain locus on chromosome 7. During α-chain rearrangement, the δ-chain genes are deleted. ---
Which of the following are located in chromosome 7 within human T-cell receptors? Options
- Alpha (α)-locus
- Beta (β)-locus
- Gamma (γ)-locus
- A & B
- B & C
Answer: A. The α-chain locus (which contains the δ-chain genes) is located on chromosome 7. The β-chain is on chromosome 7, and γ-chain is on chromosome 7. ---
Which of the following is NOT true of T-cell receptors, when compared to immunoglobulin? Options
- Prior to exposure to antigen, there are multiple V region gene segments
- Prior to exposure to antigen, somatic recombination of gene segments occurs
- Prior to exposure to antigen, there is junctional variability
- Prior to exposure to antigen, there are multiple combination of chains
- After exposure to antigen, there is somatic hypermutation and class switching
Answer: E. TCRs do NOT undergo somatic hypermutation or class switching after antigen exposure, unlike immunoglobulins. TCRs maintain their original structure and specificity. ---
Which of the following is a transmembrane glycoprotein that serves as a co-receptor for the T cell receptor (TCR), and is also known as a cytotoxic T cell (CTL)?
- CD8
- CD4
- CD3
- CD19
Answer: A. CD8 is a co-receptor primarily found on cytotoxic T cells (CTLs) and some regulatory T cells. It binds to MHC class I molecules, stabilizing the interaction between the T cell and the antigen-presenting cell.