SARS-CoV-2 infection induces sustained humoral immune responses in convalescent patients following symptomatic COVID-19

Jun Wu,Yang Wu,Xin Zheng,Xiaoli Yang,Yaohui Fang,Huan Wang,Shū Shěn ,Wenqing Zhou,Ulf Dittmer,Fei Deng,Dongliang Yang,Di Liu,Sihong Lu,Xuecheng Yang,Hua Wang,Boyun Liang,Bin Zhu,Jia Liu,Cunrong Chen,Mengji Lu,Qi Chen,Adalbert Krawczyk,Baoju Wang,Huadong Li,Shumeng Li ,Mirko Trilling,Wei Li,Liangkai Chen

doi:10.1038/s41467-021-22034-1

Abstract

Long-term antibody responses and neutralizing activities in response to SARS-CoV-2 infection are not yet clear. Here we quantify immunoglobulin M (IgM) and G (IgG) antibodies recognizing the SARS-CoV-2 receptor-binding domain (RBD) of the spike (S) or the nucleocapsid (N) protein, and neutralizing antibodies during a period of 6 months from COVID-19 disease onset in 349 symptomatic COVID-19 patients who were among the first be infected world-wide. The positivity rate and magnitude of IgM-S and IgG-N responses increase rapidly. High levels of IgM-S/N and IgG-S/N at 2-3 weeks after disease onset are associated with virus control and IgG-S titers correlate closely with the capacity to neutralize SARS-CoV-2. Although specific IgM-S/N become undetectable 12 weeks after disease onset in most patients, IgG-S/N titers have an intermediate contraction phase, but stabilize at relatively high levels over the 6 month observation period. At late time points, the positivity rates for binding and neutralizing SARS-CoV-2-specific antibodies are still >70%. These data indicate sustained humoral immunity in recovered patients who had symptomatic COVID-19, suggesting prolonged immunity.

Highlights

Long-term antibody responses and neutralizing activities in response to SARS-CoV-2 infection are not yet clear
In order to investigate antibody responses toward SARSCoV-2 over time, a total of 585 samples—obtained from 349 symptomatic COVID-19 patients—collected up to 26 weeks after disease onset were analyzed for immunoglobulin M (IgM) and IgG recognizing the receptor-binding domain (RBD) of the S protein as well as IgM and IgG binding the N protein (IgM-N and IgG-N, respectively)
We found that SARS-CoV-2specific IgM recognizing S and N was only transient and disappeared around week 12

Summary

Introduction

Long-term antibody responses and neutralizing activities in response to SARS-CoV-2 infection are not yet clear. We quantify immunoglobulin M (IgM) and G (IgG) antibodies recognizing the SARS-CoV-2 receptor-binding domain (RBD) of the spike (S) or the nucleocapsid (N) protein, and neutralizing antibodies during a period of 6 months from COVID-19 disease onset in 349 symptomatic COVID-19 patients who were among the first be infected world-wide. The positivity rates for binding and neutralizing SARS-CoV-2-specific antibodies are still >70%. These data indicate sustained humoral immunity in recovered patients who had symptomatic COVID-19, suggesting prolonged immunity. As has been consistently shown in shortterm studies, a seroconversion of IgG and IgM occurs about 2–3 weeks after disease onset[3] and IgM levels drop significantly earlier than IgG titers[4] It is unclear which antibody type (IgG or IgM) performs best in the epidemiologic identification of convalescent patients. The reported peak of IgM responses was assigned to different time points ranging from 2 to 5 weeks[2,3,5]

Methods

Results

Conclusion