Biology subjects

Linley, J. E.

Publications and source records attributed to Linley, J. E..

3 recordsLinked to original sources

bioRxiv2026

Molecular mechanism of action of a blood brain barrier shuttle antibody

The transferrin receptor has emerged as a prime target for transcytosis of antibody shuttles from the bloodstream into the brain parenchyma to deliver therapeutic payloads that treat neurological disorders. However, how the transferrin receptor-antibody binding mode impacts avidity, degradation, pH sensitivity and delivery remains underexplored. To address this, we determined the cryo-EM structure of mouse transferrin receptor 1 bound to the model brain shuttle antibody 8D3. In combination with cell binding and localisation studies we show that 8D3 can structurally support small-scale inter-receptor cross-linking, such as in self-contained pairs, that cause avidity but do not induce receptor redistribution or degradation. The structure can also explain pH-dependent binding modes, and we show how some of these antibody variants with graded sensitivities regulate brain penetration in vivo. Overall, our study illuminates how distinct molecular features of antibody binding impact transferrin receptor behaviour and brain delivery to inform on future shuttle design.

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↗

bioRxiv2022

Pregabalin silences oxaliplatin-activated sensory neurons to relieve cold allodynia

Oxaliplatin is a platinum-based chemotherapeutic agent that causes cold and mechanical allodynia in up to 90% of patients. Silent NaV1.8-positive nociceptive cold sensors have been shown to be unmasked by oxaliplatin and other neuropathic insults. This event has been causally linked to the development of cold and mechanical allodynia. Pregabalin is an anti-epileptic and analgesic drug that acts through a calcium channel 2{delta}-1 subunit to lower neurotransmitter release. Recent data also suggest pregabalin can act on NMDA receptors and other proteins, but the site of analgesic action has been considered to be the central nervous system. We examined the effects of pregabalin on oxaliplatin-evoked unmasking of cold sensitive neurons using mice expressing GCaMP-3 driven by a Pirt promoter in all sensory neurons. We found that in mice treated with oxaliplatin, intravenous injection of pregabalin significantly decreased cold allodynia. Interestingly, pregabalin also decreased the number of sensory neurons responding to cold nociceptive stimuli by altering their excitability and their temperature thresholds. These silenced neurons are medium/large cells responding to both painful mechanical and cold stimuli, corresponding to the "silent" cold sensors that become active in numerous neuropathic pain models. Deletion of 2{delta}-1 subunits abolished the effects of pregabalin on both cold allodynia and the silencing of sensory neuron unmasked by oxaliplatin. Taken together, these results define a novel, peripheral inhibitory effect of pregabalin on the excitability of silent cold-sensing neurons in a model of oxaliplatin-dependent cold allodynia. Abbreviated SummaryIseppon et al. report a novel, peripheral effect of pregabalin on oxaliplatin-dependent cold allodynia. The drug exerts its effect by silencing a specific sub-population of neurons responding to cold and mechanical stimuli in the dorsal root ganglion, and this effect is dependent on the 2{delta}-1 subunit of voltage-gated calcium channels.

neuroscience↗