Biology subjects

Certo, M.

Publications and source records attributed to Certo, M..

5 recordsLinked to original sources

bioRxiv2026

Lactate promotes IL-8 secretion in human alveolar macrophages through GPR132 and lipid metabolic reprogramming

Alveolar macrophages are the primary lung immune cell. They play a crucial role in both maintenance of tissue homeostasis and the initiation of inflammation, secreting multiple immune mediators including the chemokine interleukin-8 (IL-8). Inflammatory settings are often characterised by tissue hypoxia, increased glycolytic rates and lactate secretion, yet how lactate influences alveolar macrophage function remains unclear. Here we investigated how lactate, once considered a waste-product, shapes alveolar macrophage function. To do so, primary human alveolar macrophages (hAMs) and a combination of flow cytometry, ELISA/Luminex, western blot, light microscopy, bioluminescence resonance energy transfer (BRET) and analysis of publicly available datasets were used to understand the role of lactate in lung pathological environments. We demonstrate that hAMs sense extracellular lactate via the expression of different lactate transporters (e.g. MCT1, MCT4) and receptors (i.e. GPR132). Lactate treatment of hAMs increased IL-8 secretion in a MCT1-dependent manner. Lipid metabolism and lipid droplet formation, as well as direct lactate-driven GPR132 signalling were required for lactate-dependent IL-8 release. Our findings uncover a previously unrecognised dual mechanism by which lactate orchestrates immune regulation in hAMs. Specifically, lactate-driven IL-8 production requires two distinct lactate-driven processes: uptake via MCT1, which reprograms lipid metabolism, and signaling through the lactate receptor GPR132. This functional integration of lactate transport and receptor-mediated signaling provides new mechanistic insight into lactates role in hAM biology and highlights potential targets for therapeutic intervention.

immunology↗

bioRxiv2025

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↗

bioRxiv2023

Optimizing 5'UTRs for mRNA-delivered gene editing using deep learning

mRNA therapeutics are revolutionizing the pharmaceutical industry, but methods to optimize the primary sequence for increased expression are still lacking. Here, we design 5UTRs for efficient mRNA translation using deep learning. We perform polysome profiling of fully or partially randomized 5UTR libraries in three cell types and find that UTR performance is highly correlated across cell types. We train models on all our datasets and use them to guide the design of high-performing 5UTRs using gradient descent and generative neural networks. We experimentally test designed 5UTRs with mRNA encoding megaTALTM gene editing enzymes for two different gene targets and in two different cell lines. We find that the designed 5UTRs support strong gene editing activity. Editing efficiency is correlated between cell types and gene targets, although the best performing UTR was specific to one cargo and cell type. Our results highlight the potential of model-based sequence design for mRNA therapeutics.

synthetic biology↗

bioRxiv2023

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↗

bioRxiv2019

Synthetic cassettes for pH-mediated sensing, counting and containment

AbstractAs pH is fundamental to all biological processes, pH-responsive bacterial genetic circuits enable precise sensing in any environment. Where unintentional release of engineered bacteria poses a concern, coupling pH sensing to expression of a toxin creates an effective bacterial containment system. Here, we present a pH-sensitive kill switch (acidic Termination of Replicating Population; acidTRP), based on the E. coli asr promoter, with a survival ratio of less than 1 in 106. We integrate acidTRP with cryodeath to produce a two-factor containment system with a combined survival ratio of less than 1 in 1011 whilst maintaining evolutionary stability. We further develop a pulse-counting circuit with single cell readout for each administered stimulus pulse. We use this pulse-counter to record multiple pH changes and combine it with acidTRP to make a two-count acid-sensitive kill switch. These results demonstrate the ability to build complex genetic systems for biological containment.

synthetic biology↗