biostudies-literatureSherman JDIDCRC Early Career Investigator Pilot AwardInfectious Diseases Clinical ResearchNIAID NIH HHSLondon International Coordinating CentreComplex Carbohydrate Research CenterDefense Health Programgovernments of DenmarkNIAIDDepartment of DefenseSeoul National University HospitalNIGMS NIH HHSofae626https://www.ebi.ac.uk/biostudies/studies/S-EPMC11528514biostudies-literatureUnknown11(11)<h4>Background</h4>Severe coronavirus disease 2019 (COVID-19) and multisystem inflammatory syndrome (MIS-C) are characterized by excessive inflammatory cytokines/chemokines. In adults, disease severity is associated with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)-specific immunoglobulin G (IgG) Fc afucosylation, which induces proinflammatory cytokine secretion from innate immune cells. This study aimed to define spike IgG Fc glycosylation following SARS-CoV-2 infection in adults and children and following SARS-CoV-2 vaccination in adults and the relationships between glycan modifications and cytokines/chemokines.<h4>Methods</h4>We analyzed longitudinal (n = 146) and cross-sectional (n = 49) serum/plasma samples from adult and pediatric COVID-19 patients, MIS-C patients, aOpen forum infectious diseasesAltered Spike Immunoglobulin G Fc N-Linked Glycans Are Associated With Hyperinflammatory State in Adult Coronavirus Disease 2019 and Multisystem Inflammatory Syndrome in Children.PMC11528514UM1AI14868975N91020F00010UM1AI148576R24 GM137782R24GM137782HHSN261200800001EMRC_UU_12023/23UM1AI148575UM1AI148685UM1AI14868475N91019F00130UM1AI148452UM1AI148573UM1 AI148689UM1AI14845075N910D00024Sherman JDPanjwani AWang DHuerta CRostad CAKarmali VCollins MHRouphael NSimon TWCiric CRAnderson EJScherer EMAzadi PJohnson BBechnak SKumar BfalseAltered Spike Immunoglobulin G Fc N-Linked Glycans Are Associated With Hyperinflammatory State in Adult Coronavirus Disease 2019 and Multisystem Inflammatory Syndrome in Children.<h4>Background</h4>Severe coronavirus disease 2019 (COVID-19) and multisystem inflammatory syndrome (MIS-C) are characterized by excessive inflammatory cytokines/chemokines. In adults, disease severity is associated with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)-specific immunoglobulin G (IgG) Fc afucosylation, which induces proinflammatory cytokine secretion from innate immune cells. This study aimed to define spike IgG Fc glycosylation following SARS-CoV-2 infection in adults and children and following SARS-CoV-2 vaccination in adults and the relationships between glycan modifications and cytokines/chemokines.<h4>Methods</h4>We analyzed longitudinal (n = 146) and cross-sectional (n = 49) serum/plasma samples from adult and pediatric COVID-19 patients, MIS-C patients, a2024-01-01T00:00:00Z2024 Nov2025-04-04T20:38:49.011Z2025-04-04T20:38:49.011ZS-EPMC115285143949445710.1093/ofid/ofae626