title: Circulating blood monocytes traffic to and participate in the periprosthetic tissue inflammation.
abstract: OBJECTIVE
  To examine the trafficking of human circulating blood monocytes and their influence on the inflammation of periprosthetic tissues using a novel mouse-human chimera model.
  
  
  METHODS
  Periprosthetic tissue and bone chips from patients with aseptic prosthetic loosening were implanted into the muscles of immune-deficient SCID mice depleted of host macrophages by periodic intraperitoneal injection of anti-asialo GM1 rabbit sera (ASGM1). Autologous patient peripheral blood monocytes (PBMCs) were labeled with PKH2 fluorescent dye and injected intraperitoneally into the implanted animals. Mice were sacrificed 14 days after PBMC transfusion for molecular and histological analyses.
  
  
  RESULTS
  Patient periprosthetic tissues were well tolerated in SCID mice and preserved a high level of viability. Cell trafficking studies revealed the accumulation of fluorescent PBMC within the xenografts, with total cell counts in the xenografts significantly increased following the systemic PBMC infusion. PBMC infusion also promoted the expression of IL-1, IL-6, TNFalpha, and RANK within the periprosthetic tissue.
  
  
  CONCLUSIONS
  Systemic PBMC migrated to the implanted periprosthetic tissues and contributed to the local inflammation. The data provide evidence that circulating blood monocytes may play a role in pathologic process during aseptic loosening of total joint replacement.
authors.affiliation: Shandong University School of Medicine, Jinan, China.
authors.forename: Kai
authors.initials: K
authors.lastname: Zhang
authors.forename: Tang-Hong
authors.initials: TH
authors.lastname: Jia
authors.forename: David
authors.initials: D
authors.lastname: McQueen
authors.forename: Wei-Ming
authors.initials: WM
authors.lastname: Gong
authors.forename: David C
authors.initials: DC
authors.lastname: Markel
authors.forename: Paul H
authors.initials: PH
authors.lastname: Wooley
authors.forename: Shang-You
authors.initials: SY
authors.lastname: Yang
mesh_terms: D000818:Animals; D005260:Female; D005456:Fluorescent Dyes / Q000378:metabolism; D006801:Humans; D007249:Inflammation / Q000276:immunology*; D007595:Joint Prosthesis; D051379:Mice; D016513:Mice, SCID; D009000:Monocytes / Q000166:cytology / Q000276:immunology*; D011475:Prosthesis Failure; D012333:RNA, Messenger / Q000378:metabolism; D011817:Rabbits; D011897:Random Allocation; D014183:Transplantation, Heterologous / Q000276:immunology*
chemical_list: D005456:Fluorescent Dyes; D012333:RNA, Messenger