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Mauro, C.

Publications and source records attributed to Mauro, C..

2 recordsLinked to original sources

Utilizing combined spatial transcriptomics to elucidate localized immune responses within human coronary arteries throughout the progression of atherosclerosis

Atherosclerosis is a complex inflammatory disease characterized by the accumulation of lipids and immune cells in the arterial wall, leading to the narrowing and stiffening of blood vessels. The involvement of both innate and adaptive immunity in the pathogenesis of human atherosclerosis is increasingly recognised. However, the spatial organization and specific roles of immune cells during the various stages of disease progression remain poorly understood, underscoring the necessity for additional research to elucidate their functions throughout the disease course. A better understanding of the immune responses contribution to atherosclerosis progression could unveil novel therapeutic targets to mitigate plaque development and rupture, ultimately reducing the burden of cardiovascular events. In this study, we utilised NanoString GeoMx(R) and CosMx technologies to analyse serial sections of human coronary arteries from patients with varying degrees of atherosclerotic lesion severity. Our work consists of a series of investigations, and integrated findings from both the GeoMx(R) and CosMx datasets, including pathway analyses, cell typing, and neighbourhood analysis. This workflow underscores the power of combining these spatial transcriptomics platforms to elucidate biological processes at the single-cell level, hence unbiasedly providing molecules and pathways of relevance to aid in the understanding of disease pathogenesis and assessing the opportunity of novel therapies.

immunology↗

BCAT1 inhibition affects CD8+ T cell activation, exhaustion, and tumoral immunity by altering iron homeostasis

The present study explores the role of the cytosolic branched chain amino acid aminotransferase (BCAT1) in CD8+ T cell activation, in general, and tumor immunity, in particular, and identifies a non-canonical function of the protein in iron homeostasis. Pharmacologic inhibition of BCAT1 using the novel drug ERG245 abrogates the effector functions of CD8+ T cells in vitro and metabolically reprograms the cells towards increased OXPHOS. In vivo, it suppresses activation of CD8+ T cells in DSS colitis leading to improved disease outcomes. Remarkably, withdrawal of BCAT1 inhibition further amplifies OXPHOS and gives rise to CD8+ T cells with increased cytotoxicity in vitro and in vivo. When combined with an anti-PD-1 treatment, temporal BCAT1 inhibition dramatically increases anti-PD-1 efficacy inducing complete and durable tumor regressions in the moderately immunogenic CT26 tumor model. Single cell RNA-seq data link expression of Bcat genes to exhausted T cells within the tumor microenvironment of human cancer patients, whereas in vitro assays indicate that BCAT1 inhibition partially prevents the adoption of a terminally exhausted phenotype by CD8+ T cells. We propose BCAT1 as a target for cancer combinatory therapies. SIGNIFICANCEThe study explores for the first time the role of BCAT1 in CD8+ T cell activation and proposes novel strategies for using BCAT1 inhibitors in cancer and beyond. It demonstrates that BCAT1 exerts its function without significantly altering branched chain amino acid (BCAA) levels through a mechanism that controls iron homeostasis, a novel non-canonical mechanism of action, and implicates BCAT1 in the adoption of an exhausted phenotype by T cells found in human cancers. While the majority of metabolic drugs temper OXPHOS, it demonstrates that an agent that increases OXPHOS in CD8+ T cells can be used successfully as an immune-oncology drug.

immunology↗