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How do stem cells in bone marrow give rise to lymphocytes?

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Diagram of the human lymphatic system highlighting lymphatic vessels and major lymphoid organs, including lymph nodes, adenoids, tonsils, thymus gland, spleen, appendix, bone marrow, and ducts. — lymphatic system The human lymphatic system, showing the lymphatic vessels and lymphoid organs.

All lymphocytes originate from hematopoietic stem cells located in the bone marrow. These stem cells generate progeny that, depending on the balance of growth factors in their environment, commit to becoming lymphocytes through a series of complex transformations.123

Once these cells begin their development, their maturation pathways diverge:

B lymphocytes: These cells remain in the bone marrow to undergo maturation before exiting to the secondary lymphoid organs.14
T lymphocytes: These cells migrate from the bone marrow to the thymus, where they undergo further growth and maturation before proceeding to other lymphoid organs.14

After reaching maturity, both B and T lymphocytes are transported via the bloodstream to secondary lymphoid organs, such as the spleen and lymph nodes, where they can be activated by antigens.14