Lymphocytes

Lymphocytes are one of many types of white blood cells, which possess antigen binding cell-surface receptors. They, along with antigen presenting cells (APCs), are responsible for generation of an effective immune response.

Lymphocytes give rise to the following immunologic attributes:

(1) antigen specificity,

(2) diversity,

(3) immunologic memory and

(4) self/nonself recognition.

Bone marrow and thymus provide the sites for lymphocyte maturation, and are called primary or central lymphoid. Organs. The mature lymphocytes migrate to spleen and lymph nodes, which constitute the secondary or peripheral lymphoid tissues; the Band T cells are present in discrete areas of these organs.
In addition, some tissues normally contain fewer (-10%) lymphoid cells than secondary lymphoid organs, but they can import lymphoid cells during an inflammatory response; these are called tertiary lymphoid tissues.

Cutaneous associated lymphoid tissues are the most prominant among such tissues. Lymphocytes are the major cell type of lymph nodes, and they lie, in a fine meshwork called reticulum. These cells circulate through body, passing between blood and lymphatic vascular systems at the lymph nodes.