The main difference between B and T lymphocytes is, B lymphocytes arise from the marrow of bone and humoral immunity of the body. They are actually formed by the division of plasma cells. T cells arise from the bone marrow of thymus.
What is B Lymphocytes?
They arise from the bone marrow, gut associated lymphoid tissue. They form the humoral immunity of the body. The viruses and bacterias which enter the blood or lymph of the body, humoral immunity works against it. The plasma cells divide and form these cells which do not move to the site of infection themselves. The B cells secrete plasma cells. B cells are usually in the nodes and come into play when a foreign organism attacks the body. Eventually the plasma cells are converted into memory B cells. Once a certain type of organism hits the body’s immune system, it is memorized by those memory cells and our body develops immunity against it. They are important component of adaptive immune system.
What is T Lymphocytes?
They are also WBCs, known as lymphocytes, important component in cell mediated immunity. T cells are matured in the thymus and T cell receptors are present on the surface of these cells. Some T cells are helper cells and they actually kill the infected or cytotoxic cells. HIV also destroyed the T lymphocytes and weakens our immune system. Lymphocyte count increases in viral infections. Apart from viruses, they also act against Protists and fungi when they enter the cells. The lymphoblasts divide and form helper, killer and suppressor cells. Killer cells even react against any transplant after graft rejection. Suppressor cells suppress the immune system.
- B lymphocytes are formed in the marrow of bone while T lymphocytes are formed in the marrow of thymus.
- T cells kill the infected cells while B cells produces antibodies that react with antigens.
- HIV targets T cells and not B cells.
- There are no memory cells in T lymphocytes but memory cells are formed in B lymphocytes.
- T lymphocytes are matured in thymus while B cells in the nodes.
- When B cells secrete antibodies, they are termed as plasma cells but T cells are not termed as plasma cells.
- T cells help in graft rejections and also in eliminating cancer cells. While B cells do not play any role in such conditions.