title: Regulation of early complement components C3 and C4 in the synovium.
abstract: To determine the cytokine inducibility of early complement component (C3 and C4) expression in the synovium, explant tissue was maintained in culture for 7 days. C3 and C4 production was measured by specific enzyme-linked immunosorbent assay, and RNA was evaluated by semiquantitative PCR. The effects of leukemia inhibitory factor (LIF), gamma interferon (IFN-gamma), IFN-alpha, and estrogen on C3 and C4 expression were evaluated. C3 levels were unaffected by 7 days of LIF, IFN-gamma, or IFN-alpha treatment. In contrast, C4 levels were significantly induced in synovial samples treated for 7 days with either IFN-gamma or IFN-alpha. LIF had no effect on C4 levels in this system. Estrogen was found to down-modulate the induction of expression due to IFN-gamma. These data provide evidence for cytokine regulation of C4 expression in the synovium and for estrogen modulation of those effects.
authors.affiliation: Department of Pediatrics, Johns Hopkins University School of Medicine, Baltimore, Maryland 21205, USA.
authors.forename: T
authors.initials: T
authors.lastname: Collins
authors.forename: J A
authors.initials: JA
authors.lastname: Winkelstein
authors.forename: K E
authors.initials: KE
authors.lastname: Sullivan
mesh_terms: D001483:Base Sequence; D003176:Complement C3 / Q000096:biosynthesis* / Q000235:genetics; D003181:Complement C4 / Q000096:biosynthesis* / Q000235:genetics; D046508:Culture Techniques; D017931:DNA Primers / Q000235:genetics; D004797:Enzyme-Linked Immunosorbent Assay; D004958:Estradiol / Q000494:pharmacology; D005786:Gene Expression Regulation / Q000187:drug effects; D006131:Growth Inhibitors / Q000494:pharmacology; D006801:Humans; D007370:Interferon Type I / Q000494:pharmacology; D007371:Interferon-gamma / Q000494:pharmacology; D015850:Interleukin-6; D053605:Leukemia Inhibitory Factor; D008222:Lymphokines / Q000494:pharmacology; D008969:Molecular Sequence Data; D016133:Polymerase Chain Reaction; D011994:Recombinant Proteins; D013583:Synovial Membrane / Q000187:drug effects / Q000276:immunology*; D013585:Synovitis / Q000235:genetics / Q000276:immunology
chemical_list: D003176:Complement C3; D003181:Complement C4; D017931:DNA Primers; D006131:Growth Inhibitors; D007370:Interferon Type I; D015850:Interleukin-6; C507837:LIF protein, human; D053605:Leukemia Inhibitory Factor; D008222:Lymphokines; D011994:Recombinant Proteins; D004958:Estradiol; D007371:Interferon-gamma