title: Synoviocyte derived granulocyte macrophage colony stimulating factor mediates the survival of human lymphocytes.
abstract: Synoviocytes have been shown to be effector cells capable of synthesizing and secreting a variety of cytokines and growth factors. We demonstrate here that synoviocyte derived conditioned medium has immunoregulatory properties as it enhances human peripheral blood lymphocyte survival in a dose dependent manner in vitro. The effect elicited by synoviocyte derived conditioned medium from patients with rheumatoid arthritis (RA) was greater than that induced by synoviocyte derived conditioned medium from patients with osteoarthritis. Granulocyte-macrophage colony stimulating factor (GM-CSF) was found in synoviocyte derived conditioned medium with significantly higher levels present in synoviocyte derived conditioned medium from patients with RA. Recombinant human GM-CSF induced survival of human lymphocytes in vitro and a monoclonal antibody to human GM-CSF fully abrogated synoviocyte derived conditioned medium induced survival. Our results demonstrate that synoviocyte derived GM-CSF may be important in the retention of lymphocytes, which is a central pathological characteristic of the rheumatoid joint.
authors.affiliation: Department of Pathology, McMaster University, Hamilton, ON, Canada.
authors.forename: A
authors.initials: A
authors.lastname: Agro
authors.forename: M
authors.initials: M
authors.lastname: Jordana
authors.forename: K H
authors.initials: KH
authors.lastname: Chan
authors.forename: G
authors.initials: G
authors.lastname: Cox
authors.forename: C
authors.initials: C
authors.lastname: Richards
authors.forename: H
authors.initials: H
authors.lastname: Stepien
authors.forename: A M
authors.initials: AM
authors.lastname: Stanisz
mesh_terms: D001172:Arthritis, Rheumatoid / Q000473:pathology; D002455:Cell Division / Q000187:drug effects; D002470:Cell Survival / Q000187:drug effects; D002478:Cells, Cultured; D003470:Culture Media / Q000494:pharmacology; D004247:DNA / Q000378:metabolism; D004305:Dose-Response Relationship, Drug; D016178:Granulocyte-Macrophage Colony-Stimulating Factor / Q000378:metabolism / Q000494:pharmacology / Q000502:physiology*; D006801:Humans; D008214:Lymphocytes / Q000166:cytology* / Q000187:drug effects / Q000502:physiology; D010003:Osteoarthritis / Q000473:pathology; D011994:Recombinant Proteins / Q000494:pharmacology; D013582:Synovial Fluid / Q000166:cytology* / Q000378:metabolism; D013936:Thymidine / Q000378:metabolism; D013997:Time Factors; D014316:Tritium
chemical_list: D003470:Culture Media; D011994:Recombinant Proteins; D014316:Tritium; D016178:Granulocyte-Macrophage Colony-Stimulating Factor; D004247:DNA; D013936:Thymidine