BACKGROUND Erythroferrone (ERFE) is an erythroid hormone putatively involved in stress erythropoiesis. Its regional clearance and circulating form in humans, as well as levels in normal health and coronary disease remain unclear. METHODS To establish a reference interval, ERFE was measured in 155 healthy volunteers using the Intrinsic LifeSciences ELISA. To identify trans-organ gradients in ERFE, regional blood sampling was undertaken in patients (n = 13) undergoing clinically indicated cardiac catheterisation. The Intrinsic ELISA was assessed for reproducibility, stability, linearity and possible cross-reactivity, interference and anticoagulant effects. Circulating forms of ERFE were evaluated by HPLC. RESULTS In healthy individuals, the median concentration of ERFE was 0.51 ng/mL (IQR: 0.12-1.25), with men (n = 78) having higher levels than women (n = 77) (0.67 vs 0.32 ng/mL, p = 0.0001). ERFE concentrations in trans-organ sampling revealed no clear organ of clearance or production. Samples with high endogenous ERFE levels were suppressed by haemoglobin (≥2 g/L), bilirubin (≥200 µmol/L), lipaemia (>1 g/L), and freeze thawing (≥2 cycles), but this was not observed with low ERFE concentrations. Endogenous ERFE immunoreactivity was 46% higher in EDTA plasma compared with serum and lithium heparin plasma. On SE-HPLC, ERFE eluted as intact and cleaved forms. CONCLUSION We provide a useful reference range for ERFE in EDTA plasma. We found no specific site of secretion or clearance. The Intrinsic ELISA performed adequately but is limited by interference and stability when endogenous levels are high. Circulating forms are multiple and complex.

中文翻译：

---

分析和生物学评估循环中的人红铁蛋白。

背景技术赤铁ferrone（ERFE）是一种可能参与应激性红细胞生成的红系激素。其在人类中的区域清除和循环形式，以及正常健康和冠心病的水平仍不清楚。方法为了建立参考间隔，使用内在生命科学ELISA方法在155名健康志愿者中测量了ERFE。为了确定ERFE中的跨器官梯度，对接受临床指示的心脏导管插入术的患者（n = 13）进行了局部血液采样。评估了内在ELISA的可重复性，稳定性，线性和可能的​​交叉反应性，干扰和抗凝作用。ERFE的循环形式通过HPLC评估。结果在健康个体中，ERFE的中位数浓度为0.51 ng / mL（IQR：0.12-1.25），男性（n = 78）的水平高于女性（n = 77）（0.67 vs 0.32 ng / mL，p = 0.0001）。跨器官采样中的ERFE浓度未显示清除或清除的明显器官。内源性ERFE水平高的样品被血红蛋白（≥2g / L），胆红素（≥200μmol/ L），血脂（> 1 g / L）和冻融（≥2个周期）抑制，但未观察到ERFE浓度低。与血清和肝素锂血浆相比，EDTA血浆中的内源性ERFE免疫反应性高46％。在SE-HPLC上，ERFE以完整和裂解的形式洗脱。结论我们为EDTA血浆中的ERFE提供了有用的参考范围。我们没有发现分泌或清除的具体部位。内源性ELISA表现良好，但是当内源性水平较高时，其干扰和稳定性会受到限制。流通形式是多种多样且复杂的。