Polyclonal Vβ21.3 expansion in multisystem inflammatory syndrome in children despite SARS-CoV-2 vaccination.

ABSTRACT: Multisystem inflammatory syndrome in children (MIS-C) is a severe SARS-CoV-2-associated condition that shares clinical features with Kawasaki disease (KD), characterised by a distinct polyclonal expansion of Vβ21.3+ T cells. We report five patients diagnosed with breakthrough MIS-C despite COVID-19 immunisation, all within a limited time period at the beginning of the Omicron wave, to assess whether breakthrough MIS-C cases share the same TCR Vβ21.3 skewing seen in non-vaccinated MIS-C cases. We retrospectively reviewed five MIS-C patients hospitalised between December 2021 and April 2022 despite previous immunisation against SARS-CoV-2 (BNT162b2, an mRNA vaccine against S-protein). Immunophenotyping, including TCR Vβ subset distribution, was performed in four patients.Patients (100% male,

SUBMITTER: Netea S 

PROVIDER: S-EPMC12506441 | biostudies-literature | 2025 Oct

REPOSITORIES: biostudies-literature