title: Regulation of transforming growth factor-beta 1 and its receptor by cyclosporine in human T lymphocytes.
abstract: Scarring, fibrosis, and immunosuppression occurs with chronic cyclosporine (CsA) administration. We postulated that CsA may induce transforming growth factor (TGF)-beta 1 secretion from human T lymphocytes, a cytokine with immunoregulatory effects that has been implicated in the pathogenesis of wound healing and scarring. TGF-beta 1 was measured in serum-free supernatants harvested from T lymphocytes stimulated in the presence of CsA by a specific sandwich ELISA. CsA (10-1000 ng/ml) enhanced TGF-beta 1 secretion by approximately 40-80% in a dose-dependent manner. Increased TGF-beta 1 secretion in the presence of CsA was accompanied by a 2- to 4-fold increase in TGF-beta 1 mRNA levels due to both enhancement of its nuclear transcription as well as prolongation of TGF-beta 1 mRNA half-life. To determine whether the increase in TGF-beta 1 secretion was also accompanied by a concomitant change in its receptor, TGF-beta 1 receptor expression was analyzed by cross-linking of radioiodinated TGF-beta 1. Unactivated T lymphocytes expressed both a 105-kDa and a 65-kDa TGF-beta receptor. Upon stimulation, a transient increase in receptor density was seen at 12 hr, followed by a decline at later time points. Cells treated with CsA exhibited at least 2-fold higher levels of TGF-beta receptors in a dose-dependent manner. Thus, CsA enhances the production of TGF-beta 1 protein as well as the expression of its receptor in activated T lymphocytes. Enhanced TGF-beta 1 production and binding may contribute to the immunosuppressive and fibrosis-promoting effects of CsA therapy.
authors.affiliation: Kidney Disease Section, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, Maryland 20892, USA.
authors.forename: S S
authors.initials: SS
authors.lastname: Ahuja
authors.forename: S
authors.initials: S
authors.lastname: Shrivastav
authors.forename: D
authors.initials: D
authors.lastname: Danielpour
authors.forename: J E
authors.initials: JE
authors.lastname: Balow
authors.forename: D T
authors.initials: DT
authors.lastname: Boumpas
mesh_terms: D000328:Adult; D016572:Cyclosporine / Q000494:pharmacology*; D006801:Humans; D007166:Immunosuppressive Agents / Q000494:pharmacology*; D008213:Lymphocyte Activation / Q000187:drug effects; D012333:RNA, Messenger / Q000378:metabolism; D018125:Receptors, Transforming Growth Factor beta / Q000502:physiology*; D013601:T-Lymphocytes / Q000187:drug effects* / Q000378:metabolism / Q000648:ultrastructure; D013997:Time Factors; D014158:Transcription, Genetic / Q000187:drug effects; D016212:Transforming Growth Factor beta / Q000096:biosynthesis / Q000235:genetics / Q000502:physiology*; D015854:Up-Regulation / Q000187:drug effects
chemical_list: D007166:Immunosuppressive Agents; D012333:RNA, Messenger; D018125:Receptors, Transforming Growth Factor beta; D016212:Transforming Growth Factor beta; D016572:Cyclosporine