Answer: Specialized T cells (CD4+CD25+FoxP3+) that suppress immune responses, preventing autoimmunity and excessive inflammation.
- A T cells whose primary biological role is to further activate and stimulate other nearby T cells over time in most textbook accounts
- B Specialized T cells (CD4+CD25+FoxP3+) that suppress immune responses, preventing autoimmunity and excessive inflammation
- C T cells that differentiate into antibody-secreting plasma cells under sustained cytokine stimulation during normal conditions
- D T cells that mostly migrate to and reside mainly within the bone marrow stroma over time as generally observed in typical laboratory settings
Correct answer: B. Specialized T cells (CD4+CD25+FoxP3+) that suppress immune responses, preventing autoimmunity and excessive inflammation
Explanation: T regulatory cells express FoxP3 transcription factor and suppress immune responses. They prevent autoimmunity by suppressing self-reactive T cells that escape thymic deletion. They also suppress excessive inflammation. Deficiency leads to autoimmune diseases; cancer uses Tregs to evade immunity.
An antibody is Y-shaped, with two identical antigen-binding sites at the tips of the variable regions - each shaped to recognise one specific antigen - while the constant (Fc) region at the base is recognised by immune cells to trigger further responses.
Concept context
Innate and adaptive immunity, B cells, T cells, antibodies, vaccines, and immune disorders. Critical for NEET.