Typical Plasma Cells Research Articles

Cutaneous manifestations of multiple myeloma.

Multiple myeloma is characterized by either a focal or a diffuse abnormal overgrowth of plasma cells, occurring predominantly in the 40- to 70-year age group. Features of this disease, not dermatological, are (1) pain in the bones, (2) pathological fracture, (3) neurologic manifestations, (4) gastrointestinal symptoms, (5) fever, (6) splenomegaly and hepatomegaly, (7) lymphadenopathy, (8) extramedullary lesions, (9) roentgen abnormalities, (10) kidney abnormalities, and (11) pulmonary involvement. The characteristic cells of the relatively benign, chronic multiple myelomas are the typical plasma cells, according to Campbell and Good.1 They are characterized by four simultaneous structural features: 1. Heavy plaque-like chromatin aggregations in the nucleus, with sharp boundaries (in contradistinction to the chromatin lumps seen in lymphocytes); these account for the well-known cartwheel nucleus. 2. Intense basophilia of the cytoplasm. 3. The presence of a clear space in the nucleus, usually in the widest

STUDIES ON ANTIBODY PRODUCTION

After an antigenic stimulus, antibody is first demonstrable in the cytoplasm, and often in a spot in the nucleus, of large, immature cells in the medullary areas of the lymph node draining the site of injection. Morphologically, these cells have basophilic cytoplasm and a large nucleus, and are typical hematogenous stem cells. As these cells multiply and differentiate, the concentration of antibody in their cytoplasm increases, until colonies of typical mature plasma cells containing antibody have developed. There is a marked difference between the primary and the secondary responses, the former characterized by the development of very few antibody-containing cells while in the latter there are hundreds in a similar area. The morphology of the cells involved in both responses is identical. Occasionally, antibody was also found in low concentration in association with the lymphoid follicles. The implications of these findings for an understanding of antibody synthesis are discussed.