Plasma cells are terminally differentiated B-lymphocytes that produce large quantities of antibodies. They are widely distributed in connective tissue throughout the body, especially in the gastrointestinal tract.
Plasma cells are retained in the tissue in which they differentiated. They are not known to migrate from tissue to tissue. In the periphery, they have a short life span of only 10 to 30 days.
However, some activated B-lymphocytes ultimately return to bone marrow as differentiated plasma cells. There they receive support and nourishment in a specialized bone marrow niche. This allows a longer life span of 90 to 300 days.
Large, round to oval cells (20 µm diameter)
Small, dense, eccentric nucleus with peripherally dispersed heterochromatin with "clock-face" pattern
Voluminous cytoplasm that is pale blue to blue-grey
Enlarged Golgi apparatus seen as a pale region adjacent to the nucleus