Post-infectious inflammatory disease in MIS-C features elevated cytotoxicity signatures and autoreactivity that correlates with severity

A. Ramaswamy, N. Brodsky, T. Sumida, M. Comi, H. Asashima, K. Hoehn, N. Li, Y. Liu, A. Shah, N. Ravindra, J. Bishai, A. Khan, W. Lau, B. Sellers, N. Bansal, R. Sparks, A. Unterman, V. Habet, A. Rice, J. Catanzaro, H. Chandnani, M. López, N. Kaminski, C. D. Dela Cruz, J. Tsang, Z. Wang, X. Yan, S. Kleinstein, D. van Dijk, R. Pierce, D. Hafler, C. Lucas

medRxiv, 2020

Multisystem inflammatory syndrome in children (MIS-C) is a life-threatening post-infectious complication occurring unpredictably weeks after mild or asymptomatic SARS-CoV2 infection in otherwise healthy children. Here, we define immune abnormalities in MIS-C compared to adult COVID-19 and pediatric/adult healthy controls using single-cell RNA sequencing, antigen receptor repertoire analysis, unbiased serum proteomics, and in vitro assays. Despite no evidence of active infection, we uncover elevated S100A-family alarmins in myeloid cells and marked enrichment of serum proteins that map to myeloid cells and pathways including cytokines, complement/coagulation, and fluid shear stress in MIS-C patients. Moreover, NK and CD8 T cell cytotoxicity genes are elevated, and plasmablasts harboring IgG1 and IgG3 are expanded. Consistently, we detect elevated binding of serum IgG from severe MIS-C patients to activated human cardiac microvascular endothelial cells in culture. Thus, we define immunopathology features of MIS-C with implications for predicting and managing this SARS-CoV2-induced critical illness in children.

Cited by 10 publications.

Field of study: Medicine

10.1101/2020.12.01.20241364