113: Combining human and mouse models to dissect the role of neurovascular interactions in arthritis pain

Topic: Basic Science
Subtopic: Pain category (ICD-11), Chronic primary musculoskeletal pain, , , , , , Developing methodology/technology, Neuroimmunology, Assessment and Measurement of Pain/Nociception, , ,

Background and Aims: Current therapies against rheumatoid arthritis (RA) effectively reduce inflammation. However, in many individuals, this does not translate into reduction or resolution of joint pain. Pathological neovascularization has long been a target of interest for RA treatment. Changes in vascular structure persist beyond the classical inflammatory response, and these altered neurovascular interactions may contribute to driving persistent joint pain. Following evidence that pericytes are involved in pain in a nerve injury model[1], we aim to determine whether joint vascular changes contribute to long lasting neuronal sensitization and pain in RA.

Methods: Inflammatory arthritis was induced in PdgfrBCre-TdTomato mice using the adjuvant induced arthritis (AIA) model. Ipsilateral and contralateral knees were collected and cleared using KneEZ Clear [2] and imaged using a lightsheet microscope.
In vitro studies used human induced pluripotent stem cell (iPSC)-derived sensory neurons generated using the Chambers protocol [3] and iPSC-derived blood vessel organoids generated using the Wimmer protocol [4]. Blood vessel organoids were incubated with inflammatory cytokines (IL1, TNF, IL-17A) for 24h, prior to conditioned media collection and RNA collection.

Results: Cytokine stimulation of blood vessel organoids caused the release of pro-inflammatory mediators such as IL-6 and LIF and led to JAK/STAT pathway activation in sensory neurons. Functional experiments using multi-electrode array recordings are ongoing. To study neurovascular remodelling, we generated a peripheral neurovascular organoid containing sensory neurons, endothelial cells, and pericytes. Clearing and lightsheet imaging, and qPCR will be used to explore neurovascular responses to an RA-like environment. Finally, tissue clearing will be used in the AIA mouse model to visualize neurons, blood vessels and pericytes in whole knees, and investigate changes in the neurovasculature in arthritis versus control.

Conclusions: This project will describe and validate an iPSC-derived human model to investigate how neurovascular interactions in the joint contribute to persistent pain in RA. Our preliminary finding that blood vessel-derived factors can cause molecular changes in sensory neurons, may help us uncover new targets to more effectively combat chronic pain in RA.

References: 1. Villa-Hernandez, S., et al., A role for fibroblast and mural cell subsets in a nerve ligation model of neuropathic pain? Brain Behav Immun, 2025. 129: p. 15-29.
2. Younis, J., et al., KneEZ Clear, an Effective Tissue Clearing Protocol to Study Musculoskeletal Tissues in the Mouse. bioRxiv, 2025.
3. Chambers, S.M., et al., Combined small-molecule inhibition accelerates developmental timing and converts human pluripotent stem cells into nociceptors. Nat Biotechnol, 2012. 30(7): p. 715-20.
4. Wimmer, R.A., et al., Generation of blood vessel organoids from human pluripotent stem cells. Nat Protoc, 2019. 14(11): p. 3082-3100.

Presenting Author: Irene Zebochin
Submitting Author: Irene Zebochin

Senior Author: Franziska Denk

IASP 2026 Global Year theme of Neuropathic Pain: No

• Julia Vlachaki Walker - King's College London
• Rosie Ross - King's College London
• Tessa Rattunde - King's College London
• Leonie Taams - King's College London
• Franziska Denk - King's College London