The plasmocytes (sometimes called plasmatic cells or plasmatocytes ) are white globules Sang.

These cells is producing of Anticorps, and they are the final stage of differentiation of the lymphocytes B. With the difference of other Lymphocytes B, which present their antibodies to the level of their membrane surface, the plasmocytes are able to produce soluble antibodies. Moreover, these cells are characterized by an incapacity of proliferation (contrary at other stages of activation of the lymphocytes). The marker characterizing them is the expression of the CD138 or syndecan-1 a receiver of the extracellular matrix. These plasmocytes are produced in spleen of the mammals and migrate in osseous marrow or they can survive several months, thus allowing a long-term defense of the organization.