Coronavirus disease 2019 (COVID-19) exhibits variable symptom severity ranging from asymptomatic to life-threatening, yet the relationship between severity and the humoral immune response is poorly understood. We examined antibody responses in 113 COVID-19 patients and found that severe cases resulting in intubation or death exhibited increased inflammatory markers, lymphopenia, pro-inflammatory cytokines, and high anti-receptor binding domain (RBD) antibody levels. Although anti-RBD immunoglobulin G (IgG) levels generally correlated with neutralization titer, quantitation of neutralization potency revealed that high potency was a predictor of survival. In addition to neutralization of wild-type SARS-CoV-2, patient sera were also able to neutralize the recently emerged SARS-CoV-2 mutant D614G, suggesting cross-protection from reinfection by either strain. However, SARS-CoV-2 sera generally lacked cross-neutralization to a highly homologous pre-emergent bat coronavirus, WIV1-CoV, which has not yet crossed the species barrier. These results highlight the importance of neutralizing humoral immunity on disease progression and the need to develop broadly protective interventions to prevent future coronavirus pandemics.

2019 冠状病毒病 (COVID-19) 表现出不同的症状严重程度，从无症状到危及生命，但严重程度与体液免疫反应之间的关系知之甚少。我们检查了 113 名 COVID-19 患者的抗体反应，发现导致插管或死亡的严重病例表现出炎症标志物、淋巴细胞减少、促炎细胞因子和抗受体结合域 (RBD) 抗体水平升高。尽管抗 RBD 免疫球蛋白 G (IgG) 水平通常与中和效价相关，但中和效力的定量显示，高效力是生存的预测因子。除了中和野生型 SARS-CoV-2 之外，患者血清还能够中和最近出现的 SARS-CoV-2 突变体 D614G，这表明存在交叉保护，防止任一菌株的再次感染。然而，SARS-CoV-2 血清普遍缺乏与高度同源的芽前蝙蝠冠状病毒 WIV1-CoV 的交叉中和作用，该冠状病毒尚未跨越物种屏障。这些结果凸显了中和体液免疫对疾病进展的重要性，以及制定广泛的保护性干预措施以预防未来冠状病毒大流行的必要性。