Identification of Human Immune Cell Subtypes Most Vulnerable to IL-1β-induced Inflammatory Signaling Using Mass Cytometry

Abstract

IL-1β has emerged as a key mediator of the cytokine storm linked to high morbidity and mortality from COVID-19 and blockade of the IL-1 receptor (IL-1R) with Anakinra has entered clinical trials in COVID-19 subjects. Yet, knowledge of the specific immune cell subsets targeted by IL-1β and IL-1β-induced signaling pathways in humans is limited. Utilizing mass cytometry (CyTOF) of human peripheral blood mononuclear cells, we identified effector memory CD4 T cells and CD4 -CD8 low/-CD161 + T cells as the circulating immune subtypes with the greatest expression of p-NF-κB in response to IL-1β stimulation.Notably, CCR6 distinctly identified T cells most responsive to IL-1β. Other subsets including CD11c myeloid dendritic cells (mDCs), classical monocytes (CM), two subsets of natural killer cells (CD16 -CD56 bright CD161and CD16 -CD56 dim CD161 + ) and a population of lineage -(Lin-) cells expressing CD161 and CD25 also showed IL-1β-induced expression of p-NF-kB. The IL-1R antagonist, Anakinra significantly inhibited IL-1β-induced p-NF-kB in the CCR6 + T cells and CD11c mDCs with a trending inhibition in CD14 monocytes and Lin -CD161 + CD25 + cells. IL-1β also induced a rapid but much less robust increase in p-p38 expression as compared to p-NF-kB in the majority of these same immune cell subsets. Prolonged IL-1β stimulation greatly increased p-STAT3 and to a much lesser extent p-STAT1 and p-STAT5 in T cell subsets, monocytes, DCs and the Lin -CD161 + CD25 + cells suggesting IL-1βinduced production of downstream STAT-activating cytokines, consistent with its role in cytokine storm.Interindividual heterogeneity and inhibition of this activation by Anakinra raises the intriguing possibility that assays to measure IL-1β-induced p-NF-kB in CCR6 + T cell subtypes could identify those at higher risk of cytokine storm and those most likely to benefit from Anakinra therapy.

The Virological, Immunological, and Imaging Approaches for COVID-19 Diagnosis and Research

“…These data might permit the development of therapeutics targeting the IL-1R, which has been implicated in the cytokine storm often observed in severe COVID-19 patients. 84 …”

“…These data might permit the development of therapeutics targeting the IL-1R, which has been implicated in the cytokine storm often observed in severe COVID-19 patients. 84 Single-Cell RNA Sequencing. Single-cell RNA sequencing (scRNAseq) has been widely used to explore gene expression profiles at the cellular level.…”