title: Effects of a PEGylated soluble TNF receptor type 1 (PEG sTNF-RI) on cytokine expression in adjuvant arthritis.
abstract: OBJECTIVE
  To investigate the effects of TNF blocking therapy on synovial immune activity in rat adjuvant arthritis (AA) by measuring mRNA expression of key macrophage and T cell cytokines during PEG sTNF-RI treatment (10mg/kg) on days 8, 10 and 12.
  
  
  METHODS
  Paw volume was assessed every 3-4 days. Ankles were removed for quantitative radiology and histology and synovial membrane removed to determine cytokine mRNA expression using semi-quantitative RT-PCR. T cells in joints were quantified by immunohistochemistry.
  
  
  RESULTS
  Paw volume was significantly decreased in rats treated with PEG STNF-RI from days 12 to 17. Histology scores and synovial T cell numbers were reduced on days 13 and 17 and radiology scores significantly reduced on day 13. Expression of synovial TNF, IFN-gamma, IL-17, IL-2 and IL-4 mRNA was unchanged in treated rats and TGF-beta expression was significantly increased at day 13.
  
  
  CONCLUSIONS
  PEG sTNF-RI attenuates AA and disease recurs after treatment ceases, similar to human rheumatoid arthritis. Continued TNF production and/or ongoing T cell activity, may explain the recrudescence of disease once treatment is stopped.
mesh_terms: D000818:Animals; D001169:Arthritis, Experimental / Q000188:drug therapy* / Q000276:immunology; D016207:Cytokines / Q000235:genetics*; D000068800:Etanercept; D015870:Gene Expression / Q000187:drug effects / Q000276:immunology; D007074:Immunoglobulin G / Q000494:pharmacology*; D008198:Lymph Nodes / Q000502:physiology; D008297:Male; D011092:Polyethylene Glycols / Q000494:pharmacology; D012333:RNA, Messenger / Q000032:analysis; D051381:Rats; D011919:Rats, Inbred Strains; D018124:Receptors, Tumor Necrosis Factor / Q000097:blood*; D047888:Receptors, Tumor Necrosis Factor, Type I; D013583:Synovial Membrane / Q000276:immunology; D053319:Tumor Necrosis Factor Decoy Receptors
chemical_list: D016207:Cytokines; D007074:Immunoglobulin G; D012333:RNA, Messenger; D018124:Receptors, Tumor Necrosis Factor; D047888:Receptors, Tumor Necrosis Factor, Type I; D053319:Tumor Necrosis Factor Decoy Receptors; C069521:recombinant human tumor necrosis factor-binding protein-1; D011092:Polyethylene Glycols; D000068800:Etanercept