Profile of Immunoglobulin G N-Glycome in COVID-19 Patients: A Case-Control Study
Haifeng Hou, Huan Yang, Pengcheng Liu, Changwu Huang, Meng Wang, Yuejin Li, Mingsong Zhu, Jing Wang, Yuan Xu, Youxin Wang, Qingwei Ma, Dong Li, Pu Liao, Wei Wang
Abstract
Coronavirus disease 2019 (COVID-19) remains a major health challenge globally. Previous studies have suggested that changes in the glycosylation of IgG are closely associated with the severity of COVID-19. This study aimed to compare the profiles of IgG N -glycome between COVID-19 patients and healthy controls. A case-control study was conducted, in which 104 COVID-19 patients and 104 age- and sex-matched healthy individuals were recruited. Serum IgG N -glycome composition was analyzed by hydrophilic interaction liquid chromatography with the ultra-high-performance liquid chromatography (HILIC-UPLC) approach. COVID-19 patients have a decreased level of IgG fucosylation, which upregulates antibody-dependent cell cytotoxicity (ADCC) in acute immune responses. In severe cases, a low level of IgG sialylation contributes to the ADCC-regulated enhancement of inflammatory cytokines. The decreases in sialylation and galactosylation play a role in COVID-19 pathogenesis via the activation of the lectin-initiated alternative complement pathway. IgG N -glycosylation underlines the complex clinical phenotypes of SARS-CoV-2 infection.