Biology subjects

Baskozos, G.

Publications and source records attributed to Baskozos, G..

8 recordsLinked to original sources

bioRxiv2026

Precision cell-state silencing of injured afferents alleviates spontaneous neuropathic pain

Excessive primary afferent activity sustains neuropathic pain, but safe and effective therapeutic inhibition has proved elusive. Realising the promise of gene therapies to meet this challenge requires strategies to identify and selectively target the neuronal populations responsible. Here, we use chemo- and optogenetic approaches to demonstrate that activity in injured afferents drives spontaneous pain but is dispensable for normal sensory function, thereby creating a therapeutic opportunity. Guided by chromatin accessibility profiling, we create an injury-responsive viral vector that confers >95% specificity for injured sensory neurons. Combined with the translationally relevant chemogenetic PSAM4-GlyR, this targeting module effectively silences hyperexcitable human sensory neurons and alleviates spontaneous neuropathic pain in mice. These findings establish precision cell-state targeting of sensory neurons as a promising therapeutic strategy for chronic pain.

neuroscience↗

bioRxiv2026

Extended maturation of the HD10.6 immortalised human dorsal root ganglion cell line enables modelling of nociceptive responses and neural injury

Human sensory neuron models are an important resource for studying pain mechanisms and axon injury and repair. Current systems are limited by accessibility, scalability, or incomplete functional maturation. The HD10.6 human dorsal root ganglion-derived immortalised cell line represents a promising alternative; however, its maturation trajectory and suitability for disease modelling remain incompletely defined. Here, we performed a longitudinal, multi-modal characterisation of HD10.6 cells during differentiation over 28 days. Bulk RNA sequencing revealed progressive transcriptional remodelling, with temporal up-regulation of neuronal and nociceptor-associated gene programmes, including ion channels implicated in pain signalling. Protein-level analyses confirmed increased expression of key nociceptor markers and neuropeptides, including TRPV1, Nav1.7, Nav1.8 and CGRP. Functional assays demonstrated the emergence of sensory neuron-like properties over time. Calcium imaging revealed increasing responsiveness to capsaicin, allyl isothiocyanate, ,{beta}-MeATP, and prostaglandin E2, while patch-clamp electrophysiology at DIV 21 after maturation showed repetitive firing of action potential and, most importantly, exhibited TTX-Resistant sodium currents. These findings establish a temporal relationship between transcriptional changes and functional competence. Finally, we evaluated the utility of HD10.6 neurons for modelling axon degeneration. Treatment with vacor-induced robust neurite degeneration, which was attenuated by pharmacological inhibition of SARM1, demonstrating engagement of conserved axon degeneration pathways. Together, our findings define the progressive maturation of HD10.6 sensory neurons and establish this system as a scalable human platform for studying nociceptor biology and SARM1-dependent axon degeneration.

neuroscience↗

bioRxiv2025

NKG2D receptor ligands are cell surface biomarkers for injured murine and human nociceptive sensory neurons

Nociceptors are primary afferent neurons that sense noxious stimuli. They can be activated by tissue injury as well as the accompanying local immune response. We have shown that following nerve injury in mice cytotoxic Natural Killer (NK) cells infiltrate the peripheral nerve and interact with stress-induced ligands of the activating receptor NKG2D (Klrk1). However, the diversity and specificity of NKG2D receptor ligands among sensory neuron subtypes, and translation of this mechanism to humans, remains unknown. We used dorsal root ganglion (DRG) neurons cultured from C57BL/6J mice of both sexes with fluorescently-labelled sensory neuron lineages (Scn10a, Mrgprd, Calca, Trpv1, Th, Thy1), as well as human induced pluripotent stem cell derived (hiPSCd)-sensory neurons after laser ablation, as in vitro models of axonal injury. We assessed expression of NKG2D ligands by quantitative polymerase chain reaction (PCR) corroborated by publicly available RNA sequencing datasets and validated with single-cell PCR. Recombinant NKG2D receptor proteins in live cell-based assays were used to reveal the subcellular membrane localisation of NKG2D ligands with quantification by a semi-automated image analysis. Functional interactions between human NK cells and sensory neurons were confirmed with co-cultures in microfluidic devices. We show that NKG2D ligands are expressed exclusively in unmyelinated DRG neurons after injury. NKG2D-receptors bound to puncta along distal neurites of injured axons enriched predominantly in Mrgprd-expressing non-peptidergic nociceptors. We observed low-level binding of human NKG2D-receptors to neurites of hiPSCd sensory neurons that increased after axonal laser ablation. Degeneration of hiPSCd sensory neurons neurites by interleukin (IL-2) primed human NK cells was prevented by an NKG2D blocking antibody. The induction and enrichment of functional NKG2D receptor ligands selectively on pathological nerve fibres could aid the diagnosis of peripheral neuropathy in chronic pain conditions, and sheds new light on the potential role of nociceptive neurons in regulating the local tissue immune microenvironment.

neuroscience↗

bioRxiv2024

Identification of SLC45A4 as a pain gene encoding a neuronal polyamine transporter.

Polyamines are regulatory metabolites with key roles in transcription, translation, cell signalling and autophagy1. They are implicated in multiple neurological disorders including stroke, epilepsy and neurodegeneration and can regulate neuronal excitability through interactions with ion channels2. Polyamines have been linked to pain showing altered levels in human persistent pain states and modulation of pain behaviour in animal models3. However, the systems governing polyamine transport within the nervous system remain unclear. In undertaking a Genome Wide Association Study (GWAS) of chronic pain intensity in the UK-Biobank we found significant association with variants mapping to the SLC45A4 gene locus. In the mouse nervous system SLC45A4 expression is enriched in all sensory neuron sub-types within the dorsal root ganglion including nociceptors. Cell-based assays show that SLC45A4 is a selective plasma membrane polyamine transporter, whilst the cryo-EM structure reveals a novel regulatory domain and basis for polyamine recognition. Mice lacking SLC45A4 show normal mechanosensitivity but reduced sensitivity to noxious heat and algogen induced tonic pain that is associated with reduced excitability of peptidergic nociceptors. Our findings thus establish a role for neuronal polyamine transport in pain perception and identify a new target for therapeutic intervention in pain treatment.

neuroscience↗

bioRxiv2024

Predicting pain genes: multi-modal data integration using probabilistic classifiers and interaction networks

Accurate identification of pain-related genes remains challenging due to the complex nature of pain pathophysiology and the subjective nature of pain reporting in humans, or inferring pain states in animals on the basis of behaviour. Here, we use a machine learning approach to identify possible "pain genes". Labelling was based on a gold-standard list of genes with validated involvement across pain conditions, and was trained on a selection of -omics (eg. transcriptomics, proteomics, etc.), protein-protein interaction (PPI) network features, and biological function readouts for each gene. Multiple classifiers were trained, and the top-performing model was selected to predict a "pain score" per gene. The top ranked genes were then validated against pain-related human SNPs to validate against human genetics studies. Functional analysis revealed JAK2/STAT3 signal, ErbB, and Rap1 signalling pathways as promising targets for further exploration, while network topological features contribute significantly to the identification of "pain" genes. As such, a PPI network based on top-ranked genes was constructed to reveal previously uncharacterised pain-related genes including CHRFAM7A and UNC79. These analyses can be further explored using the linked open-source database at https://livedataoxford.shinyapps.io/drg-directory/, which is accompanied by a freely accessible code template and user guide for wider adoption across disciplines. Together, the novel insights into pain pathogenesis can indicate promising directions for future experimental research.

bioinformatics↗

bioRxiv2022

Deep RNA-seq of male and female murine sensory neuron subtypes after nerve injury

Dorsal root ganglia (DRG) neurons have been well described for their role in driving both acute and pain. Although nerve injury is known to cause transcriptional dysregulation, how this differs across neuronal subtypes and the impact of sex is unclear. Here, we study the deep transcriptional profiles of multiple murine DRG populations in early and late pain states while considering sex. We have exploited currently available transgenics to label numerous subpopulations for fluorescent activated cell sorting (FACS) and subsequent transcriptomic analysis. Using bulk tissue samples, we are able to circumvent the issues of low transcript coverage and drop-outs seen with single cell datasets. This increases our power to detect novel and even subtle changes in gene expression within neuronal subtypes and discuss sexual dimorphism at the neuronal subtype level. We have curated this resource into an accessible database for other researchers (https://livedataoxford.shinyapps.io/drg-directory/). We see both stereotyped and unique subtype signatures in injured states after nerve injury at both an early and late timepoint. While all populations contribute to a general injury signature, subtype enrichment changes can also be seen. Within populations, there is not a strong intersection of sex and injury, but previously unknown sex differences in naive states-particularly in A{beta}-RA + A{delta}-LTMRs - still contribute to differences in injured neurons.

neuroscience↗

bioRxiv2019

Molecular and cellular correlates of human nerve regeneration: ADCYAP1 encoding PACAP enhances sensory neuron outgrowth

We only have a rudimentary understanding of the molecular and cellular determinants of human nerve regeneration. Here, we use carpal tunnel syndrome (CTS) as a human model system to prospectively evaluate correlates of neural regeneration and their relationship with clinical recovery after decompression surgery. At 6 months post-surgery, we noted a significant improvement of median nerve neurophysiological and somatosensory function. Serial skin biopsies revealed a partial recovery of intraepidermal innervation, whose extent correlated with symptom improvement. In myelinated afferents, nodal length increased postoperatively. Transcriptional profiling of the skin revealed 23 differentially expressed genes following decompression, with ADCYAP1 (encoding PACAP) being the most strongly upregulated and showing an association with regeneration of intraepidermal nerve fibres. Using human induced pluripotent stem cell-derived sensory neurons, we confirmed that PACAP significantly enhances axon outgrowth in vivo. Since PACAP signals through G-protein receptors, this pathway provides an interesting therapeutic target for human sensory nerve regeneration.

neuroscience↗

bioRxiv2017

Mapping protein interactions of sodium channel NaV1.7 using epitope-tagged gene targeted mice

The voltage-gated sodium channel NaV1.7 plays a critical role in pain pathways. Besides action potential propagation, NaV1.7 regulates neurotransmitter release, integrates depolarizing inputs over long periods and regulates transcription. In order to better understand these functions, we generated an epitope-tagged NaV1.7 mouse that showed normal pain behavior. Analysis of NaV1.7 complexes affinity-purified under native conditions by mass spectrometry revealed 267 NaV1.7 associated proteins including known interactors, such as the sodium channel {beta}3 subunit (Scn3b) and collapsin response mediator protein (Crmp2), and novel interactors. Selected novel NaV1.7 protein interactors membrane-trafficking protein synapototagmin-2 (Syt2), G protein-regulated inducer of neurite outgrowth 1 (Gprin1), L-type amino acid transporter 1 (Lat1) and transmembrane P24 trafficking protein 10 (Tmed10) together with Scn3b and Crmp2 were validated using co-immunoprecipitation and functional assays. The information provided with this physiologically normal epitope-tagged mouse should provide useful insights into the pain mechanisms associated with NaV1.7 channel function.

neuroscience↗