Chen Jing, Zhao Shuai, Yan Haiyang, Huang Yaomeng, Wei Congzhen, Liu Jiajia, Sun Jingna
Department of Clinical Laboratory, The First Hospital of Hebei Medical University, Shijiazhuang, Hebei, China; Hebei Innovation Center of Clinical Medical Laboratory Technology, Shijiazhuang, Hebei, China.
Department of Clinical Laboratory, The First Hospital of Hebei Medical University, Shijiazhuang, Hebei, China; Hebei Innovation Center of Clinical Medical Laboratory Technology, Shijiazhuang, Hebei, China.
Virus Res. 2025 Jun;356:199580. doi: 10.1016/j.virusres.2025.199580. Epub 2025 May 12.
SARS-CoV-2 nucleocapsid (N) antigen has been confirmed in the peripheral blood of patients with new coronavirus infection,yet its diagnostic and prognostic significance remains unclear. This study aimed to characterize the dynamics of SARS-CoV-2 N antigenemia in patients with novel coronavirus positivity, and to assess its potential association with clinical severity and plasma biomarker levels.
We analyzed the level of SARS-CoV-2 N antigen, spike receptor-binding domain (S-RBD) IgG, neutralizing antibodies (NAb) and tissue-damage biomarkers was assessed in 180 plasma samples from 51 SARS-CoV-2-positive individuals. Plasma antigen levels were compared with concurrent respiratory nucleic acid amplification test results.
Patients with Ct values below 30 showed significantly different serum antigen levels compared to those with Ct values above 30 (p < 0.01). However, no significant positive correlation was found between respiratory viral load and serum antigen levels. Further analysis revealed that patients with pneumonia had markedly higher serum antigen levels than those without (p < 0.0001). Additionally, serum amyloid A (SAA) and ferritin (Fe) levels were significantly elevated in the antigenemia-positive group compared to the negative group, while procalcitonin (PCT) and interleukin-6 (IL-6) levels showed no significant differences. Notably, the positivity rate of N antigen in peripheral blood peaked at 47.1% (95% CI: 37.8%-56.7%) during the first week of infection and then gradually decreased over time. Moreover, patients with severe COVID-19 exhibited significantly higher serum antigen levels than those with mild or moderate disease (p < 0.0001). Serum levels of SARS-CoV-2 S-RBD IgG and neutralizing antibodies (NAb) were also significantly higher in antigenemia-negative patients than in antigenemia-positive patients (p < 0.0001).
Our findings highlight the multifaceted role of antigenemia in SARS-CoV-2 and suggest its potential as a biomarker for disease monitoring and risk stratification.
严重急性呼吸综合征冠状病毒2（SARS-CoV-2）核衣壳（N）抗原已在新型冠状病毒感染患者的外周血中得到证实，但其诊断和预后意义仍不明确。本研究旨在描述新型冠状病毒阳性患者中SARS-CoV-2 N抗原血症的动态变化，并评估其与临床严重程度和血浆生物标志物水平的潜在关联。
我们分析了51例SARS-CoV-2阳性个体的180份血浆样本中SARS-CoV-2 N抗原、刺突受体结合域（S-RBD）IgG、中和抗体（NAb）水平，并评估了组织损伤生物标志物。将血浆抗原水平与同期呼吸道核酸扩增检测结果进行比较。
Ct值低于30的患者与Ct值高于30的患者相比，血清抗原水平存在显著差异（p<0.01）。然而，呼吸道病毒载量与血清抗原水平之间未发现显著正相关。进一步分析显示，肺炎患者的血清抗原水平明显高于无肺炎患者（p<0.0001）。此外，与阴性组相比，抗原血症阳性组的血清淀粉样蛋白A（SAA）和铁蛋白（Fe）水平显著升高，而降钙素原（PCT）和白细胞介素-6（IL-6）水平无显著差异。值得注意的是，外周血中N抗原的阳性率在感染的第一周达到峰值，为47.1%（95%CI：37.8%-56.7%），随后随时间逐渐下降。此外，重症新型冠状病毒肺炎患者的血清抗原水平明显高于轻症或中症患者（p<0.0001）。抗原血症阴性患者的SARS-CoV-2 S-RBD IgG和中和抗体（NAb）血清水平也显著高于抗原血症阳性患者（p<0.0001）。
我们的研究结果突出了抗原血症在SARS-CoV-2中的多方面作用，并表明其作为疾病监测和风险分层生物标志物的潜力。
