@article{10.1172/JCI149633, author = {Lael M. Yonker AND Tal Gilboa AND Alana F. Ogata AND Yasmeen Senussi AND Roey Lazarovits AND Brittany P. Boribong AND Yannic C. Bartsch AND Maggie Loiselle AND Magali Noval Rivas AND Rebecca A. Porritt AND Rosiane Lima AND Jameson P. Davis AND Eva J. Farkas AND Madeleine D. Burns AND Nicola Young AND Vinay S. Mahajan AND Soroush Hajizadeh AND Xcanda I. Herrera Lopez AND Johannes Kreuzer AND Robert Morris AND Enid E. Martinez AND Isaac Han AND Kettner Griswold Jr. AND Nicholas C. Barry AND David B. Thompson AND George Church AND Andrea G. Edlow AND Wilhelm Haas AND Shiv Pillai AND Moshe Arditi AND Galit Alter AND David R. Walt AND Alessio Fasano}, journal = {The Journal of Clinical Investigation}, publisher = {The American Society for Clinical Investigation}, title = {Multisystem inflammatory syndrome in children is driven by zonulin-dependent loss of gut mucosal barrier}, year = {2021}, month = {7}, volume = {131}, url = {https://www.jci.org/articles/view/149633}, abstract = {BACKGROUND Weeks after SARS-CoV-2 infection or exposure, some children develop a severe, life-threatening illness called multisystem inflammatory syndrome in children (MIS-C). Gastrointestinal (GI) symptoms are common in patients with MIS-C, and a severe hyperinflammatory response ensues with potential for cardiac complications. The cause of MIS-C has not been identified to date.METHODS Here, we analyzed biospecimens from 100 children: 19 with MIS-C, 26 with acute COVID-19, and 55 controls. Stools were assessed for SARS-CoV-2 by reverse transcription PCR (RT-PCR), and plasma was examined for markers of breakdown of mucosal barrier integrity, including zonulin. Ultrasensitive antigen detection was used to probe for SARS-CoV-2 antigenemia in plasma, and immune responses were characterized. As a proof of concept, we treated a patient with MIS-C with larazotide, a zonulin antagonist, and monitored the effect on antigenemia and the patient’s clinical response.RESULTS We showed that in children with MIS-C, a prolonged presence of SARS-CoV-2 in the GI tract led to the release of zonulin, a biomarker of intestinal permeability, with subsequent trafficking of SARS-CoV-2 antigens into the bloodstream, leading to hyperinflammation. The patient with MIS-C treated with larazotide had a coinciding decrease in plasma SARS-CoV-2 spike antigen levels and inflammatory markers and a resultant clinical improvement above that achieved with currently available treatments.CONCLUSION These mechanistic data on MIS-C pathogenesis provide insight into targets for diagnosing, treating, and preventing MIS-C, which are urgently needed for this increasingly common severe COVID-19–related disease in children.}, number = {14}, doi = {10.1172/JCI149633}, url = {https://doi.org/10.1172/JCI149633}, }