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Zuletzt geändert: 23.09.2022 https://kinderkrebsinfo.de/doi/e261534

Lymphocytes – the cells of the lymphatic system

The cells of the lymphatic system, the lymphocytes, are a subgroup of the white blood cells. They play a major role within the body’s immune defence, because they are able to target and eliminate pathogens.

Lymphocytes are formed – like all other blood cells (such as all white and red blood cells as well as the platelets) – in the bone marrow, where they arise from blood precursor cells, the so-called blood stem cells (haematopoietic stem cells) and mature in a stepwise process.

The immediate precursor cells of lymphocytes are the so-called lymphoblasts. While passing several developmental stages both in the bone marrow and in various lymphatic organs (for example lymph nodes, spleen, thymus), they change their shape and features. When their development is completed, the mature, thus functioning lymphocytes are ready to leave the bone marrow or lymphatic organs, respectively, in order to fulfill their chores in blood and tissues.

The mature T- and B-lymphocytes subsequently reach the downstream lymphatic organs, such as spleen, lymph nodes, or tonsils. Both groups of lymphocytes serve the body’s immune defence, however, with different functions.