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Biology subjects

Fali, T.

Publications and source records attributed to Fali, T..

2 recordsLinked to original sources

Enhanced inflammatory signaling driven by metabolic switch in Aicardi-Goutieres syndrome

Aicardi-Goutieres syndrome (AGS) is a genetic type I interferon (IFN)-mediated disease characterised by neurological involvement with onset in childhood. Chronic inflammation in response to uncontrolled type I IFN production is, among other things, associated with IP-10 secretion. We analysed, at the single-cell transcriptomic levels, peripheral blood samples from patients bearing AGS-causing mutations in SAMHD1, RNASEH2B or ADAR1 genes. Using machine-learning approaches and differential gene expression we identified a drastic loss of transcription factor hypoxia induced factor 1 (HIF-1) expression and activity associated with features of a metabolic switch and mitochondrial stress in monocytes/dendritic cells. Chemical stabilization of HIF-1, with a synthetic drug in an in vitro model of AGS, allowed us to reverse the energy metabolic switch, attenuate mitochondrial stress and markedly reduce IP-10 production. We therefore propose that energy metabolic switch contributes to exacerbated chronic inflammation in AGS, and that targeting this pathway might represent a promising therapeutic approach.

immunology↗

A monocyte/dendritic cell molecular signature of SARS-CoV2-related multisystem inflammatory syndrome in children (MIS-C) with severe myocarditis

SARS-CoV-2 infection in children is generally milder than in adults, yet a proportion of cases result in hyperinflammatory conditions often including myocarditis. To better understand these cases, we applied a multi-parametric approach to the study of blood cells of 56 children hospitalized with suspicion of SARS-CoV-2 infection. The most severe forms of MIS-C (multisystem inflammatory syndrome in children related to SARS-CoV-2), that resulted in myocarditis, were characterized by elevated levels of pro-angiogenesis cytokines and several chemokines. Single-cell transcriptomic analyses identified a unique monocyte/dendritic cell gene signature that correlated with the occurrence of severe myocarditis, characterized by sustained NF-{kappa}B activity, TNF- signaling, associated with decreased gene expression of NF-{kappa}B inhibitors. We also found a weak response to type-I and type-II interferons, hyperinflammation and response to oxidative stress related to increased HIF-1 and VEGF signaling. These results provide potential for a better understanding of disease pathophysiology.

immunology↗