Different Profiles of Antibodies and Cytokines Were Found Between Severe and Moderate COVID-19 Patients.

Abstract

Objectives:

Our objective was to determine the antibody and cytokine profiles in different COVID-19 patients.

Methods:

COVID-19 patients with different clinical classifications were enrolled in this study. The level of IgG antibodies, IgA, IgM, IgE, and IgG subclasses targeting N and S proteins were tested using ELISA. Neutralizing antibody titers were determined by using a toxin neutralization assay (TNA) with live SARS-CoV-2. The concentrations of 8 cytokines, including IL-2, IL-4, IL-6, IL-10, CCL2, CXCL10, IFN-γ, and TNF-α, were measured using the Protein Sample Ella-Simple ELISA system. The differences in antibodies and cytokines between severe and moderate patients were compared by t-tests or Mann-Whitney tests.

Results:

A total of 79 COVID-19 patients, including 49 moderate patients and 30 severe patients, were enrolled. Compared with those in moderate patients, neutralizing antibody and IgG-S antibody titers in severe patients were significantly higher. The concentration of IgG-N antibody was significantly higher than that of IgG-S antibody in COVID-19 patients. There was a significant difference in the distribution of IgG subclass antibodies between moderate patients and severe patients. The positive ratio of anti-S protein IgG3 is significantly more than anti-N protein IgG3, while the anti-S protein IgG4 positive rate is significantly less than the anti-N protein IgG4 positive rate. IL-2 was lower in COVID-19 patients than in healthy individuals, while IL-4, IL-6, CCL2, IFN-γ, and TNF-α were higher in COVID-19 patients than in healthy individuals. IL-6 was significantly higher in severe patients than in moderate patients. The antibody level of anti-S protein was positively correlated with the titer of neutralizing antibody, but there was no relationship between cytokines and neutralizing antibody.

Conclusions:

Our findings show the severe COVID-19 patients' antibody levels were stronger than those of moderate patients, and a cytokine storm is associated with COVID-19 severity. There was a difference in immunoglobulin type between anti-S protein antibodies and anti-N protein antibodies in COVID-19 patients. And clarified the value of the profile in critical prevention.

• Authors: Yaolin Guo, Tianyi Li, Xinyi Xia, Bin Su, Hanping Li, Yingmei Feng, Jingwan Han, Xiaolin Wang, Lei Jia, Zuoyi Bao, Jingyun Li, Yongjian Liu, Lin Li
• Journal: Frontiers in immunology (Front Immunol) Vol. 12 Pg. 723585 ( 2021) ISSN: 1664-3224 [Electronic] Switzerland
• PMID: 34489974 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)
• Copyright: Copyright © 2021 Guo, Li, Xia, Su, Li, Feng, Han, Wang, Jia, Bao, Li, Liu and Li.

Chemical References

• Antibodies, Neutralizing
• Antibodies, Viral
• Coronavirus Nucleocapsid Proteins
• Cytokines
• Immunoglobulin A
• Immunoglobulin G
• Immunoglobulin M
• Spike Glycoprotein, Coronavirus
• spike protein, SARS-CoV-2
• Immunoglobulin E

Topics

• Adult
• Aged
• Aged, 80 and over
• Antibodies, Neutralizing (blood)
• Antibodies, Viral (blood)
• COVID-19 (classification, immunology)
• Coronavirus Nucleocapsid Proteins (immunology)
• Cytokines (blood)
• Enzyme-Linked Immunosorbent Assay
• Female
• Humans
• Immunoglobulin A (blood)
• Immunoglobulin E (blood)
• Immunoglobulin G (blood)
• Immunoglobulin M (blood)
• Male
• Middle Aged
• SARS-CoV-2 (immunology)
• Severity of Illness Index
• Spike Glycoprotein, Coronavirus (immunology)