bioRxiv Science⌕ Search

Biology subjects

McMurray, J. L.

Publications and source records attributed to McMurray, J. L..

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↗

The gatekeeper to gastric cancer; gastric microbiota invade the lamina propria in Helicobacter pylori-associated gastric carcinogenesis

Stomach cancer is the fourth leading cause of cancer-related deaths worldwide. Helicobacter pylori is the main risk factor for gastric adenocarcinoma (GAC), yet the mechanism underpinning this association remains uncharacterised. Gastric intestinal metaplasia (GIM) represents the pre-cancerous stage and follows H. pylori-associated chronic gastritis (CG). Sequencing studies have revealed fewer H. pylori and more non-H. pylori bacteria in GAC. However, the spatial organisation of the gastric microbiota in health and disease is unknown. Here, we have combined RNA in situ hybridisation and immunohistochemistry to detect H. pylori, non-H. pylori bacteria and host cell markers (E-cadherin, Mucins 5AC and 2) from patients with CG (n=9), GIM (n=12), GAC and normal tissue adjacent to tumours (NATs) (n=3). Quantitative analysis of whole slide scans revealed significant correlations of H. pylori and other bacteria in CG and GIM samples. In contrast to sequencing studies, significantly fewer non-H. pylori bacteria were detected in H. pylori-negative patients. Importantly, whilst H. pylori exclusively colonised the gastric glands, non-H. pylori bacteria invaded the lamina propria in 3/4 CG and 5/6 GIM H. pylori-positive patients. Bacterial invasion was observed in 3/3 GAC samples and at higher levels than matched NATs. We propose that H. pylori holds the keys to disrupt the gastric epithelial barrier, facilitating the opportunistic invasion of non-H. pylori bacteria to the lamina propria. Bacterial invasion could be a significant driver of inflammation in H. pylori-associated carcinogenesis. This proposed mechanism would both explain the synergistic roles of H. pylori and other bacteria and redirect attempts to prevent, diagnose and treat GAC.

microbiology↗