Antibody profile in symptomatic/asymptomatic severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infected Saudi persons

Essam H Ibrahim; Mohammad Y Alshahrani; Hamed A Ghramh; Mona Kilany

doi:10.1016/j.sjbs.2021.04.080

Antibody profile in symptomatic/asymptomatic severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infected Saudi persons

Saudi J Biol Sci. 2021 Aug;28(8):4677-4682. doi: 10.1016/j.sjbs.2021.04.080. Epub 2021 May 3.

Authors

Essam H Ibrahim^{1

2

3}, Mohammad Y Alshahrani⁴, Hamed A Ghramh^{1

2

5}, Mona Kilany^{2

6}

Affiliations

¹ Biology Department, Faculty of Science, King Khalid University, P.O. Box 9004, Abha 61413, Saudi Arabia.
² Research Center for Advanced Materials Science (RCAMS), King Khalid University, P.O. Box 9004, Abha 61413, Saudi Arabia.
³ Blood Products Quality Control and Research Department, National Organization for Research and Control of Biologicals, Cairo, Egypt.
⁴ Department of Clinical Laboratory Sciences, College of Applied Medical Sciences, King Khalid University, P.O. Box 61413, Abha 9088, Saudi Arabia.
⁵ Unit of Bee Research and Honey Production, Faculty of Science, King Khalid University, P.O. Box 9004, Abha 61413, Saudi Arabia.
⁶ Department of Microbiology, National Organization for Drug Control and Research (NODCAR), Cairo, Egypt.

Abstract

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)-infected persons could be symptomatic or asymptomatic. Asymptomatic and symptomatic patients can transmit SARS-CoV-2. This study aimed to study the humoral immune response in Saudis who are Covid-19 symptomatic and asymptomatic patients. We created three types of enzyme-linked immunosorbant assays (ELISAs) to reveal IgG and IgM antibodies (Abs) against SARS-CoV-2. The developed ELISAs were designed to detect Abs against SARS-CoV-2 N, S and N + S proteins. A number of Covid-19 symptomatic (1 5 3) and asymptomatic (84) RT-PCR-confirmed patient sera were used to evaluate the ELISAs and to determine the IgG and IgM antibody profile in those patients. The sensitivity and specificity of these ELISAs were evaluated using pre-Covid-19 pandemic serum samples. The results revealed the existence of anti-SARS-CoV-2 IgG and IgM Abs in Covid-19 symptomatic and asymptomatic Saudi persons. The use of SARS-CoV-2 N and S proteins in the same ELISA greatly increased the detectability of infection. In conclusion, the Covid-19 symptomatic and asymptomatic Saudi persons demonstrated both IgG and IgM antibody profile with higher titer in symptomatic patients. The use of N + S proteins as antibody capture antigens greatly increased the ELISA sensitivity.

Keywords: Antibody profile; Asymptomatic; COVID-19; ELISA; SARS-CoV-2.