目的：由于系统性红斑狼疮（SLE）具有高度异质性且缺乏特异性临床表现，因此迫切需要寻找新的生物标志物以实现 SLE 的早期和准确诊。

方法：我们纳入 216 名受试者，包括 100 名 SLE 患者、56 名其他自身免疫性疾病患者作为疾病对照（DC）以及 60 名健康对照者（HC），通过流式细胞术测定单核细胞表面CD169、B 细胞表面 CD317 和中性粒细胞表面 CD177 的表达水平，以评估其在 SLE 诊断中的临床相关性。

结果：基于这三种分子组合的流式细胞术检测显示出良好的诊断性能，曲线下面积（AUC）为 0.9243。在训练队列中，该检测的敏感性和特异性分别为 79.2% 和96.2%；在验证队列中分别为 82.1% 和 97.3%。重要的是，该检测的诊断性能独立于抗双链 DNA（dsDNA）抗体。对于抗 dsDNA 抗体阴性的 SLE 患者，诊断的AUC 为 0.9329，在训练队列中敏感性和特异性分别为 84.5% 和 97.5%；在验证队列中分别为78.6% 和 100%。

结论：我们的研究结果可能对 SLE 诊断具有重要的临床相关性，尤其是对于抗 dsDNA 抗体检测呈阴性的疑似患者。此外，我们的研究可能为临床 SLE 诊断提供了除自身抗体检测之外的新方向，这对于其他风湿性疾病也可能具有重要的临床意义。

Objectives: There is continuous need to identifying novel biomarkers that can provide early and accurate diagnosis of systemic lupus erythematosus (SLE) due to its highly heterogenous nature and lack of specific clinical manifestations.

Methods: We enrolled 216 subjects comprising 100 patients with SLE, 56 patients with other autoimmune diseases as disease controls (DCs) and 60 healthy controls (HCs) to determine the clinical relevance of the surface expression levels of CD169 on monocytes, CD317 on B cells and CD177 on neutrophils by flow cytometry for the diagnosis of SLE.

Results: The flow cytometric assay based on the combination of three molecules displayed a favorable diagnostic performance with an area under curve (AUC) of 0.9243. The sensitivities and specificities for this assay were 79.2% and 96.2% in the training cohort, and 82.1% and 97.3% in the validation cohort, respectively. Importantly, the diagnostic performance of this assay was independent of anti-double stranded DNA(dsDNA) antibodies. The AUC for diagnosing SLE patients who were negative for anti-dsDNA antibodies was 0.9329, with a sensitivity and specificity of 84.5% and 97.5% in the training cohort, and 78.6% and 100% in the validation cohort, respectively.

Conclusion: Our findings thus may have important clinical relevance in the diagnosis of SLE, especially when the suspects were tested negative for anti-dsDNA antibodies. Further, our study may shed light on a new direction other than detection of autoantibodies for the diagnosis of SLE in clinical settings, which may have important clinical implications in regard to other rheumatoid diseases.