Polyclonal expansion of TCR Vβ 21.3 <sup>+</sup> CD4 <sup>+</sup> and CD8 <sup>+</sup> T cells is a hallmark of multisystem inflammatory syndrome in children
Marion Moreews, Kenz Le Gouge, Samira Khaldi-Plassart, Rémi Pescarmona, Anne‐Laure Mathieu, Christophe Malcus, Sophia Djebali, Alicia Bellomo, Olivier Dauwalder, Magali Perret, Marine Villard, Emilie Chopin, Isabelle Rouvet, François Vandenesch, Céline Dupieux, Robin Pouyau, Sonia Teyssedre, Margaux Guerder, Tiphaine Louazon, Anne Moulin-Zinsch, Marie Duperril, Hugues Patural, Lisa Giovannini‐Chami, Aurélie Portefaix, Behrouz Kassaï, Fabienne Venet, Guillaume Monneret, Christine Lombard, Hugues Flodrops, Jean‐Marie De Guillebon, Fanny Bajolle, Valérie Launay, Paul Bastard, Shen‐Ying Zhang, Valérie Dubois, Olivier Thaunat, Jean‐Christophe Richard, Mehdi Mezidi, Omran Allatif, Kahina Saker, Marlène Dreux, Laurent Abel, Jean‐Laurent Casanova, Jacqueline Marvel, Sophie Trouillet‐Assant, David Klatzmann, Thierry Walzer, Encarnita Mariotti‐Ferrandiz, Étienne Javouhey, Alexandre Bélot
Abstract
Consistently, the T cell expansion was not associated with specific classical HLA alleles. Thus, our data suggested that MIS-C is characterized by a polyclonal Vβ21.3 T cell expansion not directed against SARS-CoV-2 antigenic peptides, which is not seen in KD, TSS and acute COVID-19.