Summary
Cells that mature in the thymus; helper T cells coordinate immunity and cytotoxic T cells kill infected cells.
In depth
CD4 helper cells (Th1, Th2, Th17) direct responses; CD8 cytotoxic cells kill infected or cancerous cells; regulatory T cells suppress. T cells recognise peptide on MHC through their TCR. Positive and negative selection in the thymus removes unresponsive and self-reactive cells.
T cells need antigen presented on MHC. Regulatory T cells maintain tolerance. Exhausted T cells appear in chronic infection and tumours.
Example: CD8 T cells recognise virus peptides on MHC I of infected cells.
Frequently asked questions
What is T Lymphocytes?
Cells that mature in the thymus; helper T cells coordinate immunity and cytotoxic T cells kill infected cells.
Which area of biology covers T Lymphocytes, and how advanced is it?
T Lymphocytes is one of the 52 topics in Immunology & Disease. It is rated Intermediate, so it suits learners who already know the core vocabulary. Related topics in this area include Adaptive Immunity, Immunological Tolerance, B Lymphocytes.
Can you give an example of T Lymphocytes?
DiGeorge syndrome (no thymus) causes severe immunodeficiency.
What should I learn before T Lymphocytes?
Work through the Beginner topics in Immunology & Disease first, such as Immune System, Viruses, Innate Immunity, then return to T Lymphocytes. Intermediate topics assume the Beginner vocabulary.
What topics are related to T Lymphocytes?
The closest topics to T Lymphocytes are Adaptive Immunity, Immunological Tolerance, B Lymphocytes, Immunosenescence. Comparing them side by side is a good way to see how the ideas connect.
How can I check that I understand T Lymphocytes?
Read the summary and the in-depth section, then use the quick check on the interactive lesson for T Lymphocytes. To practise the whole of Immunology & Disease, use the Immunology & Disease quiz.
How is T Lymphocytes different from Adaptive Immunity?
T Lymphocytes: Cells that mature in the thymus; helper T cells coordinate immunity and cytotoxic T cells kill infected cells. Adaptive Immunity: Slower, specific defence involving lymphocytes that remember pathogens. Read both side by side and note what each one explains.
How should I study T Lymphocytes step by step?
First, read the summary and write the definition in your own words. Second, read the in-depth section and note any example. Third, compare it with Adaptive Immunity and explain the difference aloud. Finally, take the Immunology & Disease quiz and come back to this page for any question you miss.