ABSTRACT
Rheumatoid arthritis is a disease of unknown etiology with substantial evidence that T lymphocytes, specifically CD4+ cells, play an important role in the pathogenesis of the rheumatoid inflammatory process: Immunohistology of synovial membranes showed that CD4 cells are several times more numerous than those bearing the CD8 antigens and that the CD4 cells are in close apposition to major histocompatibility complex class II bearing accessory cells. Peripheral blood mononuclear cells were isolated from heparin-stabilized blood by Ficoll-Ronpacon 440 density gradient centrifugation. Cell density was adjusted to 1 x 106 cells per ml and proliferative response to mitogens, antigens, and alloantigens evaluated using standard procedures. The delayed-type hypersensitivity reaction to a battery of recall antigens disappeared in four patients during anti-CD4 monoclonal antibody treatment.
