Vessels in Middle-Earth: meeting report from the 2025 Australasian Summit on Vascular Biology and Microcirculation

Abstract

The 2025 Australasian Summit on Vascular Biology and Microcirculation, jointly hosted by the Australian Vascular Biology Society (AVBS) and the Australian and New Zealand Microcirculation Society (ANZMS), convened in Queenstown, New Zealand, bringing together researchers, clinicians, and trainees across diverse disciplines. The meeting featured plenary lectures, award finalist presentations, and thematic sessions spanning vascular pathology and therapeutic discovery, extracellular matrix dynamics, (lymph) angiogenesis, inflammation, and cerebrovascular biology. Early career researchers and PhD students showcased cutting-edge work, underscoring the vibrancy of the next generation of vascular scientists. A dedicated science communication workshop further enriched the program, promoting effective dissemination and impact of vascular biology research. This report summarises the key scientific advances presented, emerging therapeutic targets, and collaborative opportunities that are shaping the future of vascular biology in Australasia and beyond.

Introduction

In September 2025, the Australian Vascular Biology Society (AVBS) and the Australian and New Zealand Microcirculation Society (ANZMS) co-hosted the Australasian Summit on Vascular Biology and Microcirculation. In its 33rd year, this annual scientific meeting for AVBS continued its long-standing tradition of fostering research communication between scientists, clinicians, students, and trainees from a broad range of disciplines with a unifying interest in vascular biology. This 2025 meeting hosted high-level national and international speakers from the clinical and research fields of vascular biology. It also highlighted presentations from ANZMS and AVBS members, selected through abstract submissions, and showcased the top early career researchers (ECRs) and PhD students. For two and a half days, registrants gathered in the idyllic New Zealand city of Queenstown, a South Island ski town surrounded by dramatic landscapes of lakes, mountains, and alpine vistas. This beautiful venue inspired collegiality, creativity, collaboration, and another memorable gathering (Fig. 1). The meeting’s organising committee consisted of Dr Tim Murphy (University of New South Wales, ANZMS, co-Chair), Professor Claudine Bonder (Centre for Cancer Biology, AVBS, co-Chair), Dr Maria Jelinic (La Trobe University, ANZMS), Dr Siân Cartland (Heart Research Institute, AVBS), Mrs Victoria Hinkley (University of Queensland/University of the Sunshine Coast, ANZMS), and Dr Denuja Karunakaran (Monash University, AVBS). This report summarises the meeting’s key highlights, showcases emerging fields in vascular biology, and outlines potential areas for future discussion.

Figure 1.

Participants of the 2025 Australasian Summit on Vascular Biology and Microcirculation, held in Queenstown, New Zealand.

From pulse to pathology: consequences of vascular disease

The meeting opened with a plenary session by Associate Professor Mary Kavurma (Heart Research Institute), who contrasted the beauty of the Remarkables mountain range with the grim reality of a gangrenous toe, an all-too-common consequence of peripheral arterial disease (PAD). She then delivered a tour de force on how microvascular dysfunction and sex drive PAD in diabetes (1), and outlined how her team, together with the newly established Centre for PAD at the Heart Research Institute, plans to build on their recent landmark publication (2) by targeting small arteries to treat the disease. Against the dramatic mountain backdrop, their ambitions felt especially fitting. Professor Michael Hickey (Monash University) followed, demonstrating how genetic mouse models and intravital microscopy are uncovering the role of neutrophils in C3 glomerulopathy, a rare but clinically untreated condition. Associate Professor Marianne Tare (Monash University) then presented elegant techniques pioneered by her group, showing that sustained blood pressure reductions after renal denervation in spontaneously hypertensive rats arise from incomplete functional reinnervation, leading to diminished excitatory junction potentials, reduced smooth muscle depolarisation, and weakened arterial contraction. Closing the session, Professor Yugeesh Lankadeva (Florey Institute of Neuroscience and Mental Health) delivered a high-energy presentation on large-animal models of cardiopulmonary bypass (3). He made a compelling case for the need to revise surgical procedures, highlighting how bypass surgery can drive acute kidney injury through microvascular hypoxia in the renal medulla.

Matrix matters: extracellular matrix dynamics & vascular remodelling

Studies of the extracellular matrix (ECM) and vascular remodelling have reshaped vascular biology, introducing pioneering techniques (4) and changing how we view the vasculature (5). The session was chaired by Professor Michael A Hill (University of Missouri), whose seminal work has defined much of the field. The plenary was delivered by Dr Maria Jelinic (La Trobe University), who used a recently developed tissue digestion method (6) to take a multi-omic approach in characterising cell types involved in human coronary artery atherosclerosis (CAA). Her work revealed that synthetic vascular smooth muscle cells in CAA may transition into macrophage-like cells, potentially driving plaque instability. Dr Tim Murphy (University of New South Wales) then examined how ageing alters arterial mechanics and myogenic tone, key regulators of blood pressure, whose dysfunction contributes to disease (7). His current studies suggest that targeting nicotinamide adenine dinucleotide metabolism may improve arterial function and mitigate age-related decline. Building on their group’s development of polyethylene glycol–heparin hydrogels (8), Ms Shiva Taheri (Queensland University of Technology) presented a microfluidic platform to investigate tissue-specific endothelial microenvironments and interactions. Finally, Mrs Habiba Danish (Baker Heart and Diabetes Institute) extended her group’s previous work (9) on the mechanosensitive Piezo-1 channel, showing that monocytes, such as neutrophils, can form extracellular traps in a shear stress- and Piezo-1–dependent manner. Together, these presentations highlighted how combining engineering, mechanobiology, and advanced omics is driving deeper insight into ECM biology and vascular remodelling in cardiovascular disease.

Early career researcher award finalists

This ECR session provided an exciting opportunity to hear from the top-ranked abstracts submitted by Australia’s postdoctoral vascular biologists. This showcase of exciting discoveries included Dr Nathan Luque (University of Western Sydney), who shared new insights on hypertensive diseases of pregnancy. Having isolated radial arteries from uterine wall segments of normal and preeclampsia pregnant women, Dr Luque used pressure myography, immunohistochemistry, electron microscopy, and gene expression analysis to demonstrate the vascular benefits (ex vivo) of administering pravastatin. Dr Oguzhan Baltaci (Peter MacCallum Cancer Centre) provided an in-depth expose on the vasculature of the blood-brain barrier (BBB). With endothelial cells enwrapped by mural cells, Dr Baltaci used zebrafish and exquisite microscopy techniques to demonstrate the distinct roles of pericytes and vascular smooth muscle cells over the course of BBB development, maturation, and stability (10). Next, Dr Ryan Homes (University of Queensland and winner of the ANZMS ECR Award) shared the importance of microcirculation in frailty in renal transplant patients. Using MicroScan sublingual microcirculatory probes, vascular parameters of perfusion and the tortuosity of capillary twists were measured against (and correlated with) a higher frailty index (11). Building on published work from the team (12), Dr Fergus Payne (Heart Research Institute and winner of the AVBS ECR Award) shared recent developments regarding cis-WOOH, a tryptophan-derived hydroperoxide, mediating arterial relaxation via oxidation of PKG1α and identification of a downstream ion channel. Rounding out the session was Dr Pooranee Morgan (Baker Heart and Diabetes Institute), who presented an outstanding talk on their recent Nature Cell Biology publication (13), wherein lipid atlas profiling revealed that immune cell susceptibility to ferroptosis is governed by their polyunsaturated fatty acid (PUFA)-phospholipid content, with high PUFA levels conferring vulnerability and low levels providing resistance. This work has potential therapeutic opportunity to evaluate PUFA-targeted ferroptosis in cardiovascular disease, particularly atherosclerosis progression (14).

Sticky situations: platelets, endothelial cells & vascular crosstalk

This session brought together a compelling mix of translational research exploring novel mechanisms in haematopoiesis, vascular injury, metabolic disease, and thrombosis. Opening the session was plenary speaker Professor Elizabeth Gardiner (Australian National University), whose recent work describes a novel mechanism of thrombopoiesis. Highlighting the limitations of thrombopoietin (TPO) mimetics in chemotherapy-induced platelet loss, her team discovered that CX-5461, a ribosome biogenesis inhibitor, unexpectedly increased platelet counts in a preclinical myeloma model that was independent of canonical TPO signalling (15). With a second-generation compound demonstrating similar results and single-dose clinical trials showing promising platelet elevation, this work represents an exciting new therapeutic pathway to treat thrombocytopaenia. Next, Mr Ethan Italiano (Heart Research Institute) shared highlights of his groundbreaking recent study published in Nature (16), in which COVID-19-associated angiopathy was found to be driven by endothelial cell necroptosis. Using an ischaemic reperfusion injury model, the study demonstrated that endothelial cell death following injury promoted red blood cell lysis, and that genetic deletion of mixed lineage kinase domain-like pseudokinase (MLKL) reduced this. The findings paradoxically revealed that endothelial necroptosis may serve as a protective ‘endoseal’ mechanism to prevent bleeding, while also contributing to microvessel obstruction. Next, Dr Denuja Karunakaran (Monash University) presented findings from her team on the metabolic role of MLKL in obesity, demonstrating how knockdown of MLKL can have profound effects on metabolic regulation and inflammatory signalling in adipose tissue. Finally, Ms Jemma Fenwick (University of Sydney) addressed heparin-induced thrombocytopaenia (HIT), showing that HIT immune complexes activate endothelial cells through increased expression of adhesion molecules to promote thromboinflammation. Her research showed that pharmacologically targeting inflammatory signalling to block endothelial cell activation may serve as an attractive therapeutic strategy to treat HIT. Together, these presentations underscored the translational potential of targeting endothelial and haematopoietic pathways to treat blood and metabolic disorders of the vasculature.

AVBS achievement and career development award

The AVBS achievement and career development (ACD) Award is a prestigious and competitive prize (AUD$10,000) for early- to mid-career researchers that recognises significant scientific achievements and promotes future success by enabling the expansion of current high-quality research and facilitating new collaborative initiatives. The 2025 recipient, Dr Amy Baxter, is a National Heart Foundation Future Leader Fellow and Head of the Vascular Cell Death, Clearance & Inflammation Lab at La Trobe Institute for Molecular Science. In her acceptance presentation, Dr Baxter shared an exquisite overview of her research program and ambitions. With a focus on cell death and clearance in vascular diseases, Dr Baxter investigates the mechanisms of efferocytosis (cell clearance) within blood vessels using a combination of cell-based and in vivo (zebrafish and mouse) approaches, including preclinical models of cardiovascular disease. Additional work investigates how endothelial cell-derived apoptotic bodies mediate immune responses during inflammation (17), and together, she hopes to identify novel therapeutic targets for the treatment of vascular diseases including atherosclerosis, diabetes, and stroke.

Growing connections: angiogenesis and vascular expansion

The study of angiogenesis and vascular expansion is central to understanding both normal physiology and disease progression. This session covered the fundamental biology of vascular systems, pathophysiological insights, and therapeutic opportunities. Plenary speaker Professor Benjamin Hogan (Peter MacCallum Cancer Centre) presented an exquisite study (manuscript undergoing revisions) on convergent evolution, the developmental and evolutionary plasticity of lymphatic endothelial cells, and their associated immune surveillance cells. Next, Dr Kazuhide Okuda (La Trobe University) presented unpublished work investigating the effects of radiation on vascular development and regeneration. Using various zebrafish transgenic lines (18), Dr Okuda showed that irradiation induces vessel-type-specific alterations, with immune cells implicated in these varied responses. The final speaker in this session, Dr Rae Farnsworth (Peter MacCallum Cancer Centre), presented a comprehensive body of work detailing how primary solid tumours pre-emptively remodel distant microenvironments through secreted circulating factors, forming ‘pre-metastatic niches’ to support the future arrival and survival of metastatic tumour cells. With metastasising cancer cells as the tumour ‘seed’ and endothelial cell-expressed adhesion molecules providing the receptive ‘soil’ (19, 20), hotspots for cancer cell metastasis are increasingly evident and represent an opportunity for pre-emptive cancer treatment.

Storm in the system: inflammation in vascular disease

Inflammation is at the centre of numerous vascular pathologies and can be both a cause and consequence of disease. This session highlighted research across a diverse range of vascular conditions underpinned by inflammation, from neurodegeneration to coronary artery disease, covering both mechanisms of inflammatory signalling and therapeutic targeting. We first heard plenary speaker Dr Justin Rustenhoven (University of Auckland) share his insights into an intriguing biological question: how the brain clears waste. We learnt about the complex system of vascular waste trafficking that enables this process and how it is impaired in neurodegenerative diseases (21). In his presentation, Justin described the innovative methods used by his team to experimentally investigate the role of α-synuclein aggregation in driving neurodegeneration and how cytokine signalling contributes to impairments in lymphatic drainage during disease pathogenesis (22, 23). Next, Professor Levon Khachigian (University of New South Wales) presented his team’s findings on the potential therapeutic effects of a small-molecule-based cardioprotective agent, showing its strong anti-inflammatory effects, including the ability to inhibit inflammasome signalling. Professor Andrew Murphy (Baker Heart and Diabetes Institute) then shared insights from his group into how macrophages derived from aged monocytes can negatively influence atherosclerotic plaque development via mitochondrial dysfunction, highlighting the intricacies of immune cell subset diversity in driving the pathogenesis of this disease. Dr Siân Cartland (Heart Research Institute) next described a cell-death-independent, atheroprotective role of tumour necrosis factor-related apoptosis-inducing ligand (TRAIL), via its ability to suppress adaptive immune signalling. Excitingly, clinical trials are currently underway to test antibody-mediated TRAIL signalling pathway activation in the cancer setting, highlighting opportunities for similar therapeutic targeting in the context of cardiovascular disease. The final speaker for this session was Dr Christopher Stanley (Heart Research Institute), who shared his findings in endotoxaemia models on how elevated hydrogen peroxide in endothelial cells contributes to vascular dysfunction through tryptophan metabolism. Together, these presentations underscored the central role of inflammation in vascular disease and highlighted promising avenues for therapeutic intervention.

Student award finalists

In this session, exciting unpublished work was showcased by students, representing the next generation of vascular biologists in Australasia. The session was kickstarted by Mrs Victoria Hinkley (University of Queensland and the University of the Sunshine Coast, and winner of the ANZMS PhD student award), who described how she used piglets to investigate why preterm infants are highly susceptible to cardiovascular instability. She revealed that preterm birth affects the capillary ultrastructure in various organs, potentially leading to increased vascular leakage. Ms Naomi Philosof (Baker Heart and Diabetes Institute and La Trobe University) presented how she used a novel mRNA therapeutic platform to overexpress anti-inflammatory proteins to attenuate lipopolysaccharide-induced acute localised inflammation in mice. This study highlighted the immense promise of using mRNA therapeutics for treating inflammatory diseases such as atherosclerosis. Ms Charlie Ffrench (Centre for Cancer Biology, and co-winner of the AVBS PhD student award) showcased that inhibition of a novel adhesion molecule led to promising anti-cancer activity with changes to tumour vasculature in mouse models of pancreatic ductal adenocarcinoma, highlighting it as a novel therapeutic target for a highly invasive and deadly cancer (24). Mr Han Xu (Victorian Heart Institute) expanded on Dr Denuja Karunakaran’s previous work (25), which demonstrated that receptor-interacting serine/threonine-protein kinase 1 (RIPK1) knockdown is therapeutic for vascular inflammation. Mr Xu revealed that selective modulation of RIPK1 in immune cells either attenuated vascular lesions or amplified necrotic core formation in a mouse model of atherosclerosis. Building on a recent study showing increased neuropilin-1 expression in claudin-low breast cancer (26), Mr (Ngoc Minh) Long Nguyen (Queensland University of Technology) presented novel findings on how neuropilin-1 modulates vasculogenic mimicry in a mouse model of claudin-low breast cancer. Next, Ms Joanna Shu Ting Liu (Heart Research Institute, and co-winner of the AVBS PhD student award) showcased a new fast-scanning microscope-based intravital imaging technique in mice to describe, in real time, how arterial thrombus forms and revealed key roles for platelet adhesion receptors in this process. This new dynamic imaging technique will transform how haemostasis and thrombosis are studied in vivo in mice. Finally, Ms Thayana Torquato (Baker Heart and Diabetes Institute) described a new in vitro bioengineered model of calcific aortic valve disease (CAVD) (27) and used this to investigate how neutrophils respond and become activated in the aortic valve environment, driving inflammation. Overall, this highly energetic session showcased novel fundamental discoveries with the potential to be harnessed for treating vascular pathologies.

The next wave: innovations reshaping vascular research

This session highlighted ongoing investigations into how vessels develop and malfunction in disease, redefining the frontiers of vascular biology. First, plenary speaker Dr Jonathan Astin (University of Auckland) presented how he used the zebrafish model to reveal a novel, tissue-specific requirement of insulin-like growth factor (Igf) signalling in developmental lymphangiogenesis. Transcriptomic analysis revealed mechanisms for localised Igf signalling activation, driving directed lymphatic growth. Importantly, human induced pluripotent stem cell experiments showed that this pro-lymphangiogenic mechanism is conserved in mammals, highlighting the importance of investigating tissue-specific requirements of IGF signalling in mammalian lymphatic development. Next, Associate Professor Sara Baratchi (Baker Heart and Diabetes Institute) presented her recently published study in Lab on a Chip, which describes how mechanical forces are converted into biochemical signals to drive the mechanisms underlying the pathogenesis of CAVD (27). To investigate this, Associate Professor Baratchi developed new bioengineered, disease-inspired in vitro models that integrate patient-derived blood samples and valve tissues and replicate key biomechanical features of the calcifying valve (e.g. enrichment of hyaluronic acid within extracellular matrices). Of note, this model revealed that reduced tensile stress drives endothelial-to-mesenchymal transition (EndMT) in valvular endothelial cells, potentially contributing to abnormal stiffening and calcification of the aortic valve in CAVD patients. Ms Nathalie Nataren (Centre for Cancer Biology) presented pioneering work investigating tumour microenvironment features in metastatic melanoma formalin-fixed, paraffin-embedded sections from immune checkpoint inhibitor responding and non-responding patients using cutting-edge Xenium Spatial imaging (28). This study will reveal key tumour microenvironment features and pathways that contribute to therapy resistance in metastatic melanoma. Finally, Mr Kaan Ozguven (Heart Research Institute) presented novel findings describing how L-tryptophan lowers blood pressure in hypertension. He found that L-tryptophan acts through pathways driven by the tryptophan-metabolising enzyme indoleamine 2,3-dioxygenase-1, expressed in endothelial cells under inflammatory conditions (29), to lower blood pressure. This study highlights a promising therapeutic avenue for hypertension.

Mind over vessels: advances in cerebrovascular biology

The final plenary of the symposium was delivered by Professor Donald Welsh (University of Western Ontario), who presented his group’s recent work on the functional coupling of Ca²⁺ channels and its impact on myogenic (pressure-induced) vasoconstriction (30, 31). Using human and mouse arteries, and employing techniques including myography, patch clamping, and super-resolution microscopy, Professor Welsh demonstrated that clustering of Ca²⁺ channels increases their probability of opening. This so called ‘functional coupling’ was shown to involve Protein Kinase Cα, a kinase that enhances channel activation through phosphorylation and membrane trafficking. These findings advance our understanding of Ca²⁺ signalling and may provide critical insights into abnormal vascular function in disease, including traumatic brain injury. Dr Ashenafi Betrie (Florey Institute of Neuroscience and Mental Health, University of Melbourne, and the second ECR winner for ANZMS) then presented follow-up work to his high-impact publication (32) on the vascular effects of zinc. Using zinc transporter knockout mice, he showed that zinc transport plays a significant role in regulating cerebral blood flow. The symposium concluded with Mr Cameron Trought (Heart Research Institute), who addressed the therapeutic challenges of ischaemic stroke. He presented studies on natural peptides derived from bloodletting insects, which exhibit anticoagulant activity while reducing bleeding risk. These compounds, which display a unique mechanism of action, will next be tested in whole-animal models. If successful, they could expand the pharmacological arsenal for protecting against ischaemic stroke.

Conclusion

This vascular-focused scientific meeting in Queenstown was both intense and enjoyable, fostering new collaborations and inspiring fresh research ideas. The organisers curated a beautiful and well-balanced programme that featured both established and emerging researchers in the vascular biology field. The venue was amazing and scheduled at the perfect time of year to visit New Zealand, allowing many attendees to experience the beautiful Queenstown scenery both before and after the meeting. A key highlight was the Science Communication workshop held before the official start of the meeting. The expert panel members of Professor Michael A. Hill (University of Missouri), Professor Donald Welsh (University of Western Ontario), Dr Amy Baxter (La Trobe University), and Dr Vivian Tran (La Trobe University) shared valuable insights on how to build your digital presence as a scientist and effectively communicate science to enhance research visibility and impact. The session was expertly organised and chaired by Dr Maria Jelinic (La Trobe University) and was well-attended by ECRs and students. Notably, Professor Donald Welsh led an important discussion on improving the current publication system to promote transparency, accessibility, and to maximise scientific impact. Excitingly, the next AVBS/ANZMS annual scientific meeting will be integrated into the International Vascular Biology Meeting (IVBM) 2026 on September 6–10th 2026, in Adelaide, Australia. IVBM is the premier biennial meeting in the vascular biology field and will be an amazing opportunity for Australasian vascular biologists to be exposed to cutting-edge research presented by world leaders in the field. More information can be obtained from the meeting website (https://ivbm2026.com/).

Declaration of interest

The authors declare that there is no conflict of interest that could be perceived as prejudicing the impartiality of the work reported.

Funding

This work did not receive any specific grant from any funding agency in the public, commercial, or not-for-profit sector.