Neutrophil Profiles of Pediatric COVID-19 and Multisystem Inflammatory Syndrome in Children

Boribong, B. P.; LaSalle, T. J.; Bartsch, Y. C.; Ellett, F.; Loiselle, M. E.; Davis, J. P.; Gonye, A. L. K.; Hajizadeh, S.; Kreuzer, J.; Pillai, S.; Haas, W.; Edlow, A. G.; Fasano, A.; Alter, G.; Irimia, D.; Sade-Feldman, M.; Yonker, L. M.

doi:10.1101/2021.12.18.473308

bioRxiv · 10.1101/2021.12.18.473308

Neutrophil Profiles of Pediatric COVID-19 and Multisystem Inflammatory Syndrome in Children

Boribong, B. P.·LaSalle, T. J.·Bartsch, Y. C.·Ellett, F.·Loiselle, M. E.·Davis, J. P.·Gonye, A. L. K.·Hajizadeh, S.·Kreuzer, J.·Pillai, S.·Haas, W.·Edlow, A. G.·Fasano, A.·Alter, G.·Irimia, D.·Sade-Feldman, M.·Yonker, L. M.

View original source ↗Export metadata ↓

Abstract

Multisystem Inflammatory Syndrome in Children (MIS-C) is a delayed-onset, COVID-19-related hyperinflammatory systemic illness characterized by SARS-CoV-2 antigenemia, cytokine storm and immune dysregulation; however, the role of the neutrophil has yet to be defined. In adults with severe COVID-19, neutrophil activation has been shown to be central to overactive inflammatory responses and complications. Thus, we sought to define neutrophil activation in children with MIS-C and acute COVID-19. We collected samples from 141 children: 31 cases of MIS-C, 43 cases of acute pediatric COVID-19, and 67 pediatric controls. We found that MIS-C neutrophils display a granulocytic myeloid-derived suppressor cell (G-MDSC) signature with highly altered metabolism, which is markedly different than the neutrophil interferon-stimulated gene (ISG) response observed in pediatric patients during acute SARS-CoV-2 infection. Moreover, we identified signatures of neutrophil activation and degranulation with high levels of spontaneous neutrophil extracellular trap (NET) formation in neutrophils isolated from fresh whole blood of MIS-C patients. Mechanistically, we determined that SARS-CoV-2 immune complexes are sufficient to trigger NETosis. Overall, our findings suggest that the hyperinflammatory presentation of MIS-C could be mechanistically linked to persistent SARS-CoV-2 antigenemia through uncontrolled neutrophil activation and NET release in the vasculature. One Sentence SummaryCirculating SARS-CoV-2 antigen:antibody immune complexes in Multisystem Inflammatory Syndrome in Children (MIS-C) drive hyperinflammatory and coagulopathic neutrophil extracellular trap (NET) formation and neutrophil activation pathways, providing insight into disease pathology and establishing a divergence from neutrophil signaling seen in acute pediatric COVID-19.

Source connections

Published article ↗

Explore related subjects

immunology Preprint

Keep this discovery

Explore connections, maps & timelines

BibTeX RIS

Boribong, B. P., LaSalle, T. J., Bartsch, Y. C., Ellett, F., Loiselle, M. E., Davis, J. P., Gonye, A. L. K., Hajizadeh, S., Kreuzer, J., Pillai, S., Haas, W., Edlow, A. G., Fasano, A., Alter, G., Irimia, D., Sade-Feldman, M., Yonker, L. M.. 2021-12-20. Neutrophil Profiles of Pediatric COVID-19 and Multisystem Inflammatory Syndrome in Children. https://doi.org/10.1101/2021.12.18.473308

Cite the original work for its findings. Save a collection to share your selection of sources.

KEEP EXPLORING

Related preprints

bioRxiv2026

Proliferation and mutation as humoral immune response

The affinity maturation process, through which antibodies acquire relatively high affinity for an invading pathogen, involves complex mechanisms whose relative importance is not yet fully understood. This study proposes an analytical model of this process, to investigate the main factors governing proliferation and mutation and assess their respective roles. The model suggests that the immune system should not be expected to follow a single, rigid evolutionary pattern, as a wide range of proliferation and mutation strategies can yield nearly optimal outcomes. Keywords: Antibody, antigen, affinity, B-cell, mutation, proliferation

immunology↗

bioRxiv2026

Proteome-wide discovery of novel diagnostic antigens for coccidioidomycosis

Coccidioidomycosis, commonly called Valley Fever (VF), caused by Coccidioides spp., is an understudied fungal disease that accounts for a substantial fraction of pneumonias in endemic areas. Diagnosis remains challenging because the mainstay of diagnosis is serology, and current assays have modest sensitivity in early infection. Discovery of new antigens could improve serologic detection early in disease. Here, we use PepSeq, a DNA-programmable serology platform, to represent the complete proteome of Coccidioides within a library of 244,000 DNA-barcoded peptides. By profiling antibody reactivity at the protein and epitope levels in VF patients, naturally infected pigtail macaques, and healthy controls, we identify numerous previously-unrecognized antigens and epitopes, including some shared between humans and macaque responses. When translated into a pooled peptide ELISA, we show that a subset of identified antigens can discriminate VF cases from controls in an independent cohort with high accuracy (AUC = 0.91). These findings establish high-dimensional peptide serology as a scalable approach for fungal antigen discovery and identify new targets for improved VF diagnosis.

immunology↗

bioRxiv2026

Establishing an ex vivo platform for molecular profiling of skin structural cells using frozen human skin biopsies

Skin structural cells, including keratinocytes, melanocytes, endothelial cells, and fibroblasts, play critical roles in the development of chronic inflammatory skin disease. Inflammatory stimuli induce transcriptional reprogramming and epigenetic changes in skin structural cells, which contribute to disease pathogenesis. Although two-dimensional (2D) and three-dimensional (3D) skin culture models have been widely used to investigate inflammatory responses in skin structural cells, ex vivo systems that maintain skin structure and cellular composition remain limited. To address this gap, we explored using frozen skin biopsies as an experimental platform to study the responses of skin structural cells to inflammatory stimuli. Using a simple air-liquid interface culture method on permeable Transwell inserts, we showed that viable skin structural cells that retain cell-type-specific transcriptional profiles can be recovered from frozen skin biopsies after prolonged in vitro culture. Stimulation with IFN-{gamma} induced robust transcriptional and chromatin accessibility changes that were largely resolved after stimulus removal, with transcriptional responses to secondary stimulation comparable to the primary stimulation. Treatment of cultured skin biopsies with histone-modifying enzyme inhibitors effectively altered global histone modification levels, but did not substantially affect the transcriptional resolution of IFN-{gamma}-induced responses. Collectively, these findings establish cryopreserved human skin biopsies as a scalable ex vivo platform that enables mechanistic studies of inflammatory responses of multiple populations of skin structural cells.

immunology↗