Investigating the role of neutrophil subsets in vascular inflammation

themes

2, (1)

project overview

Vascular pathologies underline devastating diseases ranging from auto-immune vasculitis to the recent COVID-19 pandemic (1). Neutrophils, as the most abundant immune cells, have been reported to intimately interact with the vascular system either via direct cell-cell contact or indirectly through release of inflammatory cytokines or cellular substances.  Fully functional mature neutrophils patrol the circulation and tissues to exert anti-microbial activity through several mechanisms including release of cytotoxic products, reactive oxygen species (ROS), neutrophil extracellular traps (NETs) and pore-forming molecules. These activities can cause vascular tissue damage if poorly controlled (2).

Inflammatory responses trigger the release of functionally distinct immature neutrophils into the circulation and tissues in different diseases, including severe COVID-19, where we, and others, identify the presence of neutrophil progenitors (3). Our recent work on auto-immune vasculitis has shown that immature neutrophils can generate dysregulated ROS to cause vascular leakage and damage that may lead to systemic vascular pathology (4). Moreover, we have unravelled novel cell-intrinsic molecular regulators of neutrophil maturation and phenotype and function that may lead to multiple therapeutic strategies tailored to specific conditions (5).

This project will profile core pathways and processes of vascular damage associated with immature neutrophils in Giant Cell Arteritis (GCA)-affected arteries by performing multiplex gene and protein expression analyses using the state-of-the-art spatial biology approaches, such as multi-parameter confocal microscopy and single cell spatial transcriptomics. Specifically the Cell Dive platform which allows for multiplex imaging of a single sample by iterative staining, will be used to expand our analysis of neutrophil- and oxidative tissue damage-associated biomarkers in GCA biopsies. Correlations between molecular signatures of vascular damage associated with immature neutrophils and treatment outcomes will be assessed in a clinically well-defined cohort and validated in an independent replication cohort (Fig overview). To further investigate the cellular and molecular mechanisms of neutrophils function on vasculature, the system of human vascular organoids will be adopted.

The outcome of this study is expected to contribute significantly to development of new targets for therapeutic interventions to prevent detrimental vascular damage that is implicated in many diseases such as auto-immune vasculitis.

KEYWORDS

Neutrophils, Vasculitis, Multiplex Imaging, Spatial transcriptomics, Vascular pathologies

TRAINING OPPORTUNITIES

The Kennedy Institute is a world-renowned research centre and is housed in a brand new state-of-the-art research facility. Training will be provided in techniques in a wide range of immunological tool kits (cell isolation, FACS, ELISA, primary cell culture) and imaging (immunofluorescence on tissue sections) approaches. This rare opportunity to develop vascular organoids will involve stem cell reprogramming and culture. The candidate can benefit from the hands-on experience with these techniques in the Udalova lab, and from access to clinical samples and expertise in their immune analysis in the Luqmani group. Primary human neutrophils and plasma will be prepared from blood samples of patients with well phenotyped forms of vasculitis recruited by Prof Luqmani's research team. Confocal microscopy will be applied routinely to validate organoid structure and to image neutrophil-vasculature interaction and vascular damages. Multiplex assays such as the Luminex assay will be used for patient plasma profiling to identify key signalling molecules that modulate neutrophil-vasculature interaction. A core curriculum of lectures will be taken in the first term to provide a solid foundation in a broad range of subjects including inflammation, genomics, epigenetics, translational immunology and data analysis. Students will attend weekly seminars within the department and those relevant in the wider University. Students will be expected to present data regularly to the department, the Genomics of Inflammation lab and to attend external conferences to present their research globally. Students will also have the opportunity to work closely with both internal and external collaborators on organoids development.

KEY PUBLICATIONS 

1. Ponte C, Martins-Martinho J, Luqmani RA. Diagnosis of giant cell arteritis. Rheumatology (Oxford). 2020 May 1;59(Supplement_3):iii5-iii16.
2. Wang L, Luqmani R, Udalova IA. The role of neutrophils in rheumatic disease-associated vascular inflammation. Nature Review Rheumatology. 2022 Mar;18(3):158-170.
3. Oxford Covid-19 Immunology Consortium. A blood atlas of COVID-19 defines hallmarks of disease severity and specificity. Cell. 2022 Mar 3;185(5):916-938.e58.
4. Wang L, Ai Z, Khoyratty T, Zec K, Eames HL, van Grinsven E, Hudak A, Morris S, Ahern D, Monaco C, Eruslanov EB, Luqmani R, Udalova IA. ROS producing immature neutrophils are linked to GCA vascular pathologies. Journal of Clinical Investigations Insight. 2020 Oct 15;5(20):e139163
5. Khoyratty T*, Ai Z*, Ballesteros I, Mathie S, Eames HL, Martín-Salamanca S, Wang L, Hemmings A, Willemsen N, von Werz V, Zehrer A, Walzog B, van Grinsven E, Hidalgo A, Udalova IA. Distinct transcription factor networks control neutrophil-driven inflammation. Nature Immunology, 2021 Sep;22(9):1093-1106.

CONTACT INFORMATION OF ALL SUPERVISORS

Professor Irina Udalova Irina.udalova@kennedy.ox.ac.uk

Professor Raashid Luqmani raashid.luqmani@ndorms.ox.ac.uk

Dr Kristina Zec Kristina.zec@kennedy.ox.ac.uk