A type of white blood cell that is part of the immune system. Lymphocytes can be subdivided into two main groups: D-lymphocytes which originate in the bone marrow and produce antibodies; T-lymphocytes which are produced in the bone marrow and mature in the thymus. Helper T-lymphocytes heighten the production of antibodies by B-lymphocytes; suppressor T-lymphocytes suppress B-lymphocyte activity and seem to be in short supply during an MS exacerbation.
