Department of Clinical Laboratory, Jinling Hospital, Clinical School of Medical College, Nanjing University, 210002 Nanjing, P. R. China.
Clin Chim Acta. 2012 Oct 9;413(19-20):1657-60. doi: 10.1016/j.cca.2012.05.006. Epub 2012 May 15.
The complexes of β₂-glycoprotein I (β₂-GPI) with lipoprotein(a) [β₂-GPI-Lp(a)] exist in human circulation and are increased in serum from patients with some autoimmune diseases. This study aims to investigate the concentration of β₂-GPI-Lp(a) in serum of children with idiopathic nephrotic syndrome (NS) and its relationship with serum lipids, oxidized lipoprotein and renal function parameters to explore the potential of the complexes as an additional marker for evaluating pediatric NS.
Serum concentrations of β₂-GPI-Lp(a) complexes and oxidized Lp(a) [ox-Lp(a)] were measured by "Sandwich" ELISAs in 80 NS children and 82 age/sex-matched healthy controls. The levels of serum lipids and kidney parameters were also determined. Multivariate logistic regression analysis was performed to identify correlate of β₂-GPI-Lp(a) and NS.
The serum concentrations of β₂-GPI-Lp(a) complexes in children with NS were significantly higher than those in controls (median 0.95 U/ml vs 0.28 U/ml, P<0.0001). Ox-Lp(a) levels were also markedly elevated (median 14.55 mg/l vs 2.60 mg/l, P<0.0001] in NS children. The concentrations of β₂-GPI-Lp(a) were positively correlated with ox-Lp(a) (r=0.246, P=0.028), but not with Lp(a) level, and the concentrations of ox-Lp(a) were positively related with Lp(a) (r=0.301, P=0.007) in NS children. Multivariate logistic regression analysis identified a positive association between NS and β₂-GPI-Lp(a) (OR=13.694, 95% CI 6.400-29.299, P<0.0001), after adjusting for kidney function parameters, serum lipids and ox-Lp(a).
Elevated β₂-GPI-Lp(a) level was an independent and significant risk factor for pediatric NS and, enhanced Lp(a) oxidation partly contributes to the formation of β₂-GPI-Lp(a) complexes.
β₂-糖蛋白 I（β₂-GPI）与脂蛋白（a）[β₂-GPI-Lp(a)]的复合物存在于人体循环中，并在某些自身免疫性疾病患者的血清中增加。本研究旨在探讨儿童特发性肾病综合征（NS）患者血清中β₂-GPI-Lp(a)复合物的浓度及其与血清脂质、氧化脂蛋白和肾功能参数的关系，以探讨该复合物作为评估儿科 NS 的潜在附加标志物的可能性。
采用“三明治”ELISA 法检测 80 例 NS 患儿和 82 例年龄/性别匹配的健康对照者血清β₂-GPI-Lp(a)复合物和氧化型 Lp(a)[ox-Lp(a)]浓度。同时测定血清脂质和肾功能参数。采用多元 logistic 回归分析确定与β₂-GPI-Lp(a)相关的因素和 NS。
NS 患儿血清β₂-GPI-Lp(a)复合物浓度明显高于对照组（中位数 0.95 U/ml 比 0.28 U/ml，P<0.0001）。NS 患儿 ox-Lp(a)水平也明显升高（中位数 14.55 mg/l 比 2.60 mg/l，P<0.0001）。NS 患儿β₂-GPI-Lp(a)浓度与 ox-Lp(a)呈正相关（r=0.246，P=0.028），但与 Lp(a)水平无关，ox-Lp(a)浓度与 Lp(a)呈正相关（r=0.301，P=0.007）。多元 logistic 回归分析发现，在调整肾功能参数、血清脂质和 ox-Lp(a)后，NS 与β₂-GPI-Lp(a)之间存在正相关（OR=13.694，95%CI 6.400-29.299，P<0.0001）。
升高的β₂-GPI-Lp(a)水平是儿童 NS 的独立和显著危险因素，Lp(a)氧化增强部分导致β₂-GPI-Lp(a)复合物的形成。
