IFNG and COVID-19–associated multisystem inflammatory syndrome in children: Immune dysregulation of MIS-C involves activation of neutrophils, macrophages, and dendritic cells with robust chemokine and cytokine production (10, 14, 20), profound lymphopenia (10), decreased IFN-α and increased IFN-γ (IFN-γ) responses (9, 10, 20).