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Lymphocytes
Medical expert of the article
Last reviewed: 05.07.2025
Lymphocytes are the main cellular element of the immune system and are formed in the bone marrow and actively function in the lymphoid tissue.
The main function of lymphocytes is to recognize foreign antigens and participate in the body's immunological response. In children up to 4-6 years of age, lymphocytes predominate in the total number of leukocytes, that is, they are characterized by absolute lymphocytosis; after 6 years, a "crossover" occurs and neutrophils predominate in the total number of leukocytes.
Lymphocytes actively participate in the pathogenesis of immunodeficiency states, infectious, allergic, lymphoproliferative, oncological diseases, transplant conflicts, and autoimmune processes. In the listed processes, the number of lymphocytes in the blood can change significantly. As a result of an adequate response to antigen stimulation, the number of lymphocytes increases - lymphocytosis, with an inadequate response, the number of lymphocytes can decrease - lymphopenia.
Reference values (norms) of absolute and relative lymphocyte content in the blood
Age |
Absolute quantity, ×10 9 /l |
Relative quantity,% |
12 months |
4-10.5 |
61 |
4 years |
2-8 |
50 |
6 years |
1.5-7 |
42 |
10 years |
1.5-6.5 |
38 |
21 years old |
1-4.8 |
34 |
Adults |
1-4.5 |
34 |
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