Which of the following statements best describes how T cell activation occurs? A) Depends solely on the antigen bound to the T cell receptor. B) Involves both antigen recognition a... Which of the following statements best describes how T cell activation occurs? A) Depends solely on the antigen bound to the T cell receptor. B) Involves both antigen recognition and a second costimulatory signal. C) Involves multiple signaling pathways regardless of antigen specificity. D) Requires only the presence of antigen presenting cells.
Understand the Problem
The question is asking for a description of the process of T cell activation, specifically which statement accurately characterizes the mechanisms involved in this biological process.
Answer
B) Involves both antigen recognition and a second costimulatory signal.
The final answer is B) Involves both antigen recognition and a second costimulatory signal.
Answer for screen readers
The final answer is B) Involves both antigen recognition and a second costimulatory signal.
More Information
T cell activation requires two key signals: antigen recognition by the T cell receptor (TCR) and a costimulatory signal provided by interactions with antigen-presenting cells (APCs). This ensures that T cells respond appropriately to pathogens and not to self-antigens.
Tips
A common mistake is to assume that T cell activation depends solely on antigen recognition. However, without the second costimulatory signal, T cells may become anergic or tolerant rather than activated.
Sources
- Helper T Cells and Lymphocyte Activation - NCBI - ncbi.nlm.nih.gov
- T Cells and MHC Proteins - Molecular Biology of the Cell - NCBI - ncbi.nlm.nih.gov
