Regulation of early complement components C3 and C4 in the synovium.
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.
Collins
T
T
Department of Pediatrics, Johns Hopkins University School of Medicine, Baltimore, Maryland 21205, USA.
Winkelstein
J A
JA
Sullivan
K E
KE
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
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