title: Synovial fluid mononuclear cells exhibit a spontaneous HLA-DR driven proliferative response.
abstract: We have tested the hypothesis that the spontaneous proliferation of synovial fluid mononuclear cells (SFMC) observed during in vitro culture is due to a mechanism analogous to the autologous mixed lymphocyte reaction (AMLR). Thus by observing the effect of addition of cyclosporin A, monoclonal anti-HLA-DR antibody, and recombinant interleukin 2 (rIL-2) on the spontaneous proliferation of SFMC from patients with rheumatoid arthritis (RA) and a wide range of seronegative spondyloarthritides (SN), we have demonstrated that this phenomenon is: (i) a T cell response, (ii) inhibited by the addition of cyclosporin A or monoclonal anti-HLA-DR antibody, (iii) enhanced by the addition of rIL-2 and (iv) the rIL-2 enhancement of the spontaneous proliferation is inhibited by a monoclonal anti-HLA-DR antibody. These observations suggest that the spontaneous proliferation of SFMC is at least in part an HLA-DR driven, IL-2 dependent event analogous to the AMLR, and support the concept derived from immunohistological studies of an important role for an antigen-presenting cell/T cell interaction occurring in the synovial membrane in inflammatory joint diseases such as RA.
mesh_terms: D001172:Arthritis, Rheumatoid / Q000276:immunology*; D002455:Cell Division; D003524:Cyclosporins / Q000494:pharmacology; D006681:HLA-D Antigens / Q000276:immunology*; D006684:HLA-DR Antigens / Q000276:immunology*; D006801:Humans; D007376:Interleukin-2 / Q000494:pharmacology; D007963:Leukocytes, Mononuclear / Q000276:immunology* / Q000378:metabolism; D008213:Lymphocyte Activation; D007959:Lymphocyte Culture Test, Mixed; D013167:Spondylitis, Ankylosing / Q000276:immunology; D013582:Synovial Fluid / Q000276:immunology*; D013601:T-Lymphocytes / Q000276:immunology; D013936:Thymidine / Q000378:metabolism
chemical_list: D003524:Cyclosporins; D006681:HLA-D Antigens; D006684:HLA-DR Antigens; D007376:Interleukin-2; D013936:Thymidine