Guillén C, McInnes I B, Kruger H, Brock J H
Department of Immunology, Western Infirmary, Glasgow.
Ann Rheum Dis. 1998 May;57(5):309-14. doi: 10.1136/ard.57.5.309.
To determine the ability of lactoferrin in rheumatoid arthritis (RA) synovial fluid to bind "free" iron, and to study the regulatory mechanisms therein that control iron homeostasis.
"Free" iron was determined by the bleomycin assay and lactoferrin concentrations by enzyme linked immunosorbent assay. The activities of iron regulatory protein (IRP) and NF-kappa B in synovial fluid cells were assayed by mobility shift assay.
30% of synovial fluids contained "free" iron and in these, lactoferrin concentrations were significantly lower than in those with no "free" iron (p < 0.01). Addition of exogenous lactoferrin consistently reduced the amount of "free" iron in positive synovial fluids. IRP activity in synovial cells did not correlate with synovial fluid iron concentrations but did correlate with NF-kappa B activation and with serum C reactive protein.
Lactoferrin may prevent iron mediated tissue damage in RA by reducing "free" synovial iron concentration when inflammatory stimuli have disregulated IRP mediated iron homeostasis.
测定类风湿性关节炎(RA)滑液中乳铁蛋白结合“游离”铁的能力,并研究其中控制铁稳态的调节机制。
采用博来霉素法测定“游离”铁,酶联免疫吸附测定法测定乳铁蛋白浓度。采用迁移率变动分析法检测滑液细胞中铁调节蛋白(IRP)和核因子κB(NF-κB)的活性。
30%的滑液含有“游离”铁,在这些滑液中,乳铁蛋白浓度显著低于无“游离”铁的滑液(p < 0.01)。添加外源性乳铁蛋白可持续降低阳性滑液中“游离”铁的含量。滑液细胞中的IRP活性与滑液铁浓度无关,但与NF-κB激活及血清C反应蛋白相关。
当炎症刺激破坏了IRP介导的铁稳态时,乳铁蛋白可能通过降低滑液中“游离”铁的浓度来预防RA中铁介导的组织损伤。