Production and regulation of monocyte chemoattractant protein-1 in lipopolysaccharide- or monosodium urate crystal-induced arthritis in rabbits: roles of tumor necrosis factor alpha, interleukin-1, and interleukin-8.
The production of monocyte chemoattractant protein-1 (MCP-1) and its regulation by TNFalpha, IL-1, and IL-8 were investigated in two rabbit models of arthritis induced by intra-articular injection of lipopolysaccharide (LPS) or monosodium urate (MSU) crystals. We first prepared recombinant rabbit MCP-1 and antibodies and then developed an immunoassay. The immunoassay detected 3 pg/ml rabbit MCP-1 and did not cross-react with other rabbit chemokines such as IL-8 or GRO. MCP-1 was first detected in synovial fluid (SF) at 1 hour, and peaked at 4 or 2 hours after the injection of LPS or MSU crystals, respectively. Immunohistochemically, MCP-1 was detected in synovial lining cells and infiltrating neutrophils. The amounts of MCP-1 detected in SF from neutrophil-depleted rabbits were similar to those in normal rabbits, suggesting that synovial lining cells were the main source of MCP-1 detected in SF. The peak level of MCP-1 in SF after LPS-injection was inhibited by 57% with anti-TNFalpha mAb and by 41% with IL-1 receptor antagonist (IL-1Ra). Coadministration of anti-TNFalpha mAb and IL-1Ra inhibited 90% of MCP-1 production. In contrast, the peak level of MCP-1 in SF after MSU crystal-injection was not affected by any cytokine inhibitor, but was reduced by 52% with coadministration of anti-TNFalpha mAb and IL-1Ra. Anti-IL-8 IgG had no effect on the production of MCP-1 in either model. Thus, the production of MCP-1 in LPS-induced arthritis was mostly regulated by TNFalpha and IL-1, whereas half the extent of MCP-1 production in MSU crystal-induced arthritis was independent of TNFalpha or IL-1. IL-8 does not seem to regulate the production of MCP-1 in SF either directly or indirectly. Finally, administration of neutralizing anti-MCP-1 antibody inhibited LPS- and MSU crystal-induced monocyte infiltration by 58.4% and 44.9%, respectively, suggesting that synovial production of MCP-1 plays an important role in the recruitment of monocytes in these arthritis models.
Department of Pathology, Kumamoto University School of Medicine, Honjo, Japan.
A
A
Matsukawa
S
S
Miyazaki
T
T
Maeda
S
S
Tanase
L
L
Feng
S
S
Ohkawara
M
M
Yoshinaga
T
T
Yoshimura
D000818:Animals; D000911:Antibodies, Monoclonal / Q000096:biosynthesis; D001168:Arthritis / Q000139:chemically induced / Q000378:metabolism* / Q000473:pathology; D019556:COS Cells; D002465:Cell Movement / Q000276:immunology; D018932:Chemokine CCL2 / Q000032:analysis / Q000096:biosynthesis* / Q000235:genetics / Q000276:immunology; D003460:Crystallization; D005260:Female; D015200:Fluoroimmunoassay; D007106:Immune Sera / Q000008:administration & dosage / Q000096:biosynthesis; D007270:Injections, Intra-Articular; D007275:Injections, Intravenous; D007375:Interleukin-1 / Q000502:physiology*; D016209:Interleukin-8 / Q000502:physiology*; D007719:Knee Joint / Q000473:pathology; D008070:Lipopolysaccharides / Q000633:toxicity*; D009000:Monocytes / Q000473:pathology; D011817:Rabbits; D011994:Recombinant Proteins / Q000032:analysis / Q000096:biosynthesis / Q000276:immunology; D013582:Synovial Fluid / Q000737:chemistry; D014409:Tumor Necrosis Factor-alpha / Q000502:physiology*; D014527:Uric Acid / Q000633:toxicity*
D000911:Antibodies, Monoclonal; D018932:Chemokine CCL2; D007106:Immune Sera; D007375:Interleukin-1; D016209:Interleukin-8; D008070:Lipopolysaccharides; D011994:Recombinant Proteins; D014409:Tumor Necrosis Factor-alpha; D014527:Uric Acid