This article highlights the work of the Bahar lab in collaboration with the Arditi lab on the molecular origin of multisystem inflammatory syndrome in children (MIS-C) observed in Covid-19 patients. The article provides an extensive perspective, including interviews with Bahar, Arditi, and other scientists.
The Bahar lab discovered a superantigenic segment on the spike glycoprotein (Cheng et al., PNAS 2020), potentially implicated in triggering MIS-C as well as the cytokine storm and hyperinflammatory immune responses observed in severe Covid-19 cases (Rivas et al J Allergy & Clinical Immunol 2021). The TCR repertoire observed in in severely infected patients (Porritt et al, J Clinical Investigation, 2021) supported the occurrence of such a superantigenic reaction. The discovery of this superantigenic segment, which shares sequence and structure similarities with Staphyloccocal enterotoxin B led to the identification of a monoclonal antibody (6D3), which proved to reduce SARS-CoV-2 infection in experiments conducted at Cedars Sinai (UCLA) (Cheng et al., Structure 2021).