Viral interleukin-10 gene inhibition of inflammation, osteoclastogenesis, and bone resorption in response to titanium particles.
OBJECTIVE
To evaluate the potential of viral interleukin-10 (vIL-10) gene therapy as an approach to prevent wear debris-induced inflammation, osteoclastogenesis, and bone resorption as it relates to periprosthetic osteolysis in patients with total joint replacements.


METHODS
Replication-defective adenovirus vectors expressing vIL-10 (AdvIL-10) or LacZ (AdLacZ) target genes were used to transduce fibroblast-like synoviocytes (FLS) in vitro, and the effects of these cells on wear debris-induced proinflammatory cytokine production and receptor activator of nuclear factor kappaB ligand + macrophage colony-stimulating factor splenocyte osteoclastogenesis were assessed by enzyme-linked immunosorbent assay and tartrate-resistant acid phosphatase assay. The effects of AdvIL-10 administration on wear debris-induced osteolysis in vivo were analyzed using the mouse calvaria model, in which AdLacZ was used as the control.


RESULTS
In the presence of AdLacZ-infected FLS, titanium particle-stimulated macrophages exhibited a marked increase in secretion of tumor necrosis factor alpha (TNFalpha) (6.5-fold), IL-6 (13-fold), and IL-1 (5-fold). Coculture with AdvIL-10-transduced FLS suppressed cytokine secretion to basal levels, while addition of an anti-IL-10 neutralizing antibody completely blocked this effect. The vIL-10-transduced FLS also inhibited osteoclastogenesis 10-fold in an anti-IL-10-sensitive manner. In vivo, titanium implantation resulted in a 2-fold increase in osteoclasts (P < 0.05) and in a 2-fold increase in sagittal suture area (P < 0.05). This increase over control levels was completely blocked in mice receiving intraperitoneal injections of AdvIL-10, all of whom had measurable serum vIL-10 levels for the duration of the experiment. Immunohistochemistry demonstrated reduced cyclooxygenase 2 and TNFalpha expression in AdvIL-10-infected animals.


CONCLUSIONS
This study demonstrates that gene delivery of vIL-10 inhibits 3 processes critically involved in periprosthetic osteolysis: 1) wear debris-induced proinflammatory cytokine production, 2) osteoclastogenesis, and 3) osteolysis.
Carmody
Emily E
EE
University of Rochester Medical Center, Rochester, New York 14642, USA.
Schwarz
Edward M
EM
Puzas
J Edward
JE
Rosier
Randy N
RN
O'Keefe
Regis J
RJ
D000256:Adenoviridae / Q000235:genetics; D000818:Animals; D002478:Cells, Cultured; D005347:Fibroblasts / Q000166:cytology; D015316:Genetic Therapy; D005822:Genetic Vectors; D007249:Inflammation / Q000139:chemically induced / Q000628:therapy; D007375:Interleukin-1 / Q000096:biosynthesis; D016753:Interleukin-10 / Q000235:genetics*; D015850:Interleukin-6 / Q000096:biosynthesis; D008264:Macrophages / Q000187:drug effects / Q000378:metabolism; D010010:Osteoclasts / Q000276:immunology*; D010014:Osteolysis / Q000139:chemically induced / Q000276:immunology / Q000628:therapy*; D012886:Skull / Q000166:cytology / Q000276:immunology; D013154:Spleen / Q000166:cytology; D013583:Synovial Membrane / Q000166:cytology; D014025:Titanium / Q000276:immunology* / Q000494:pharmacology; D014161:Transduction, Genetic; D019076:Transgenes / Q000276:immunology; D014409:Tumor Necrosis Factor-alpha / Q000096:biosynthesis; D014764:Viral Proteins / Q000235:genetics*
C066460:BCRF1 protein, Human herpesvirus 4; D007375:Interleukin-1; D015850:Interleukin-6; D014409:Tumor Necrosis Factor-alpha; D014764:Viral Proteins; D016753:Interleukin-10; D014025:Titanium