title: Cross-linking of CD137 ligand modulates immune responses of thioglycollate-elicited mouse peritoneal macrophages.
abstract: OBJECTIVE
  The aim of this study was to investigate effects of CD137 ligand (CD137L)-mediated reverse signaling on cellular responses in thioglycollate-elicited mouse peritoneal macrophages.
  
  
  METHODS
  Five-week-old male C57B6 mice were injected intraperitoneally with thioglycollate for 3 days to isolate peritoneal macrophages. We counted total cell numbers with a Cell Lab Quanta SC. CD137L expression was examined with a flow cytometer. We also measured expression of inflammatory cytokines by flow cytometry and/or real time-PCR.
  
  
  RESULTS
  Cross-linking of CD137L with recombinant CD137-Fc protein (rCD137-Fc) increased total numbers of thioglycollate-elicited mouse peritoneal macrophages (hIgG-Fc- vs. rCD137-Fc-treated group, p < 0.05). However, ligation reduced the increase in IL-1β and IL-6 levels. Real-time PCR analysis showed that treatment of cells with rCD137-Fc also reduced transcript levels of IL-1β, IL-6, iNOS and COX2 (hIgG-Fc- vs. rCD137-Fc-treated group, p < 0.05), as well as expression of CD137L.
  
  
  CONCLUSIONS
  Reverse signals initiated by CD137L negatively modulate certain immune functions of thioglycollate-elicited peritoneal macrophages.
authors.affiliation: Department of Pharmacology, Institute of Oral Biology, School of Dentistry, Kyung Hee University, Seoul, 130-701, Korea.
authors.forename: Jun-Sang
authors.initials: JS
authors.lastname: Bae
authors.forename: Hyeong-Sup
authors.initials: HS
authors.lastname: Kim
authors.forename: Jae Hong
authors.initials: JH
authors.lastname: Park
authors.forename: Sang-Hyuk
authors.initials: SH
authors.lastname: Park
authors.forename: Hyeon-Woo
authors.initials: HW
authors.lastname: Lee
mesh_terms: D053330:4-1BB Ligand / Q000737:chemistry* / Q000378:metabolism; D000818:Animals; D003432:Cross-Linking Reagents / Q000494:pharmacology*; D015536:Down-Regulation; D005434:Flow Cytometry / Q000379:methods; D007107:Immune System; D053583:Interleukin-1beta / Q000096:biosynthesis; D015850:Interleukin-6 / Q000096:biosynthesis; D008264:Macrophages / Q000378:metabolism; D017737:Macrophages, Peritoneal / Q000378:metabolism*; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D015398:Signal Transduction; D013864:Thioglycolates / Q000737:chemistry*
chemical_list: D053330:4-1BB Ligand; D003432:Cross-Linking Reagents; D053583:Interleukin-1beta; D015850:Interleukin-6; D013864:Thioglycolates