State Key Laboratory for Diagnosis and Treatment of Infectious Diseases, National Clinical Research Center for Infectious Diseases, Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, The First Affiliated Hospital, College of Medicine, Zhejiang University, 79 Qingchun Road, Hangzhou, 310003, Zhejiang Province, China.
Department of Infectious Diseases, Taizhou Hospital of Zhejiang Province Affiliated to Wenzhou Medical University, No.150 Ximen Road of Linhai City, Taizhou, 317000, China.
Virol J. 2022 Nov 13;19(1):186. doi: 10.1186/s12985-022-01921-z.
The severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) is the cause of coronavirus disease 2019 (COVID-19), which is currently a worldwide pandemic. There are limited available treatments for severe COVID-19 patients. However, some evidence suggests that intravenous immunoglobulin (IVIg) provides clinical benefits for these patients.
We administered IVIg to 23 severe COVID-19 patients, and all of them survived. Four related coronaviruses can cause the common cold. We speculated that cross-reactivity of SARS-CoV-2 and other common coronaviruses might partially explain the clinical efficacy of IVIg therapy. Thus, we performed multiple alignment analysis of the spike (S), membrane (M), and nucleotide (N) proteins from SARS-CoV-2 and the common coronaviruses to identify conserved regions. Next, we synthesized 25 peptides that were conserved regions and tested their IVIg seropositivity.
The results indicated four peptides had significant or nearly significant seropositivity, and all of them were associated with the S and M proteins. Examination of the immune responses of healthy volunteers to each synthetic peptide indicated high seropositivity to the two peptides from S protein. Blood samples from healthy individuals may have pre-existing anti-SARS-CoV-2 IgGs, and IVIg is a potentially effective therapy for severe COVID-19.
In conclusion, blood samples from many healthy individuals have pre-existing anti-SARS-CoV-2 IgGs, and IVIg may be an effective therapy for severe COVID-19.
严重急性呼吸综合征冠状病毒 2（SARS-CoV-2）是导致 2019 年冠状病毒病（COVID-19）的原因，目前该病正在全球范围内流行。对于重症 COVID-19 患者，可用的治疗方法有限。然而，一些证据表明，静脉注射免疫球蛋白（IVIg）可为这些患者提供临床益处。
我们对 23 例重症 COVID-19 患者使用了 IVIg，所有患者均存活。有 4 种相关的冠状病毒可引起普通感冒。我们推测，SARS-CoV-2 与其他常见冠状病毒之间的交叉反应可能部分解释了 IVIg 治疗的临床疗效。因此，我们对 SARS-CoV-2 和常见冠状病毒的刺突（S）、膜（M）和核苷酸（N）蛋白进行了多次比对分析，以鉴定保守区域。然后，我们合成了 25 个保守区域的肽，并测试了它们的 IVIg 血清阳性率。
结果表明，有 4 个肽具有显著或接近显著的血清阳性率，且它们都与 S 和 M 蛋白相关。对健康志愿者对每个合成肽的免疫反应的检查表明，两种来自 S 蛋白的肽具有高血清阳性率。来自健康个体的血液样本可能具有预先存在的抗 SARS-CoV-2 IgG，而 IVIg 可能是重症 COVID-19 的有效治疗方法。
总之，许多健康个体的血液样本具有预先存在的抗 SARS-CoV-2 IgG，IVIg 可能是重症 COVID-19 的有效治疗方法。
