What is the Difference Between T Lymphocytes and B Lymphocytes?

T lymphocytes and B lymphocytes, also known as T cells and B cells, are two main types of lymphocytes that play crucial roles in the immune system. They are involved in the acquired or antigen-specific immune response and have distinct functions and origins. Here are the key differences between T cells and B cells:

Origin: Both T and B cells originate in the bone marrow, but they mature in different locations. B cells mature in the bone marrow itself, while T cells travel to the thymus and mature there.
Function: B cells are responsible for producing antibodies that attack invading bacteria, viruses, and toxins. T cells, on the other hand, destroy the body's own cells that have been taken over by viruses or become cancerous. T cells also produce cytokines, which help activate other parts of the immune system.
Antigen Receptors: B cells have B cell receptors (BCRs) on their surface, while T cells have T cell receptors (TCRs).
Morphology: Both T and B cells are small cells (8-10 microns in diameter) with similar structures, including a nucleus, ribosomes, and lysosomes.
Subpopulations: T cells have two main types: helper T cells and killer T cells (also known as cytotoxic T cells). Helper T cells stimulate B cells to make antibodies and help killer cells develop, while killer T cells directly kill cells infected by pathogens. B cells have only one active type.
Life Span: B cells generally have a shorter life span compared to T cells, which have a longer life span.
Location: B cells are typically found outside the lymph nodes, while T cells are found inside the lymph nodes.

In summary, B cells play a role in producing antibodies to fight pathogens, while T cells are involved in directly attacking infected cells and activating other parts of the immune system. Both cell types are essential for a functional and healthy immune system.