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Kellaway, S.

Publications and source records attributed to Kellaway, S..

4 recordsLinked to original sources

Voluntary engagement predicts recovery across rehabilitation time points after experimental spinal cord injury

Rehabilitation is the cornerstone of clinical care following spinal cord injury (SCI) and is frequently incorporated into preclinical studies to evaluate emerging therapies. However, the variables that influence the effectiveness of rehabilitation interventions in rodent models remain poorly characterized, limiting the translational value of preclinical research. Here, we performed a meta-analysis of 150 preclinical studies comprising more than 3000 rodents and 292 effect sizes to identify such factors associated with successful rehabilitation after SCI. Rehabilitation improved functional outcomes across multiple behavioral domains, with larger effects observed in thoracic than cervical injury models. Meta-regression identified environmental enrichment as the most effective strategy, particularly when combined with task-specific training. Longer rehabilitation duration was associated with improved recovery, whereas greater daily exposure to forced rehabilitation was associated with smaller gains. In contrast, prolonged access to voluntary rehabilitation did not show this relationship. Rehabilitation improved outcomes when initiated at all time points after injury, with greater benefits when initiated during the late subacute and intermediate phases. Rehabilitation approaches associated with higher stress burden produced reduced benefits, suggesting that stress may limit rehabilitation-induced recovery. Collectively, these findings identify rehabilitation type, duration, and delivery context as important determinants of recovery after SCI and support a broad therapeutic window for intervention. Our results favor low-stress, voluntary rehabilitation strategies that promote sustained engagement and provide principles for designing effective and biologically appropriate rehabilitation strategies, potentially improving translational success for emerging SCI therapies. One Sentence SummarySustained voluntary rehabilitation promotes functional recovery across stages of experimental spinal cord injury, whereas prolonged forced training may reduce its benefits.

neuroscience↗

RUNX1 aberrations in blast-phase CML induce the RBP SPATS2L which promotes growth, survival and stress granule assembly

The RUNX1 transcription factor is a critical regulator of hematopoiesis and frequently mutated in myeloid malignancies. In the myeloproliferative neoplasm, chronic myeloid leukemia (CML), secondary somatic RUNX1 mutations and RUNX1::MECOM/EVI1, are associated with tyrosine kinase inhibitor (TKI) resistance and progression to the blast-phase (BP-CML). Research has predominantly focussed on transcriptional dysregulation mediated by RUNX1 mutations in myeloid malignancies, whilst post-transcriptional dysregulation remains comparatively unexplored. To address this, we used orthogonal organic phase separation (OOPS), to characterise the RNA-binding proteome of RUNX1 deficient BP-CML cells. RUNX1 depleted BP-CML cells exhibited significant alterations to RBP abundance involved in stress response pathways and translation/ribosome-biogenesis (RiBi). Furthermore, RUNX1 depletion or expression of RUNX1::EVI1 in BP-CML cells induced expression and RNA binding activity of SPATS2L, a component of stress granules (SG); membraneless cytoplasmic condensates protecting mRNAs from degradation, promoting survival under stress. Whilst RUNX1 depletion increased SG-assembly, SPATS2L depletion reduced SG-assembly in BP-CML cells and inhibited the growth and survival of multiple BP-CML cell lines. The translation inhibitor homoharringtonine (HHT), used historically in TKI-resistant CML, ablated SG-assembly in BP-CML cells with RUNX1 depletion, and, primary BP-CML cells with LOF/hypomorphic RUNX1 mutations (characterised by defective DNA-binding/CBF{beta}-interaction) were preferentially sensitised to HHT. Finally, suppressing SPATS2L expression induced by RUNX1 depletion, increased the HHT-sensitivity of RUNX1 depleted BP-CML cells, suggesting SPATS2L contributes to therapeutic resistance in CML with RUNX1 mutations. This study suggests that SPATS2L and SG induction could be critical to RUNX1-mutant leukemias, and, provides preliminary evidence for a mutationally-targeted approach in CML with RUNX1 aberrations.

cancer biology↗

The ratio of RUNX1-ETO oncoprotein to normal RUNX1 expression determines the balance between endothelial reprogramming and hematopoietic cell growth

In t(8;21) acute myeloid leukemia (AML) the RUNX1 DNA binding domain is fused to the RUNX1T1 protein producing the RUNX1-ETO onco-fusion protein. We previously showed that t(8;21) leukemic stem cells aberrantly activate endothelial signalling pathways to initiate blast cell proliferation. Here, we employed a human embryonic stem cell (ESC) line expressing an inducible RUNX1-ETO transgene to determine whether RUNX1-ETO directly induces endothelial signalling pathways or whether it is dependent on AML progression. Using single cell analyses we show that RUNX1-ETO induction reprograms ESC-derived myeloid progenitors towards endothelial cells. Integrated data analysis demonstrates (i) that endothelial reprogramming is RUNX1-ETO concentration-dependent and irreversible, (ii) that when RUNX1-ETO and RUNX1 expression levels are equal, a sub-population of blood progenitors escapes reprogramming and (iii) keeps proliferating when co-cultured with endothelial cells. Our experiments provide important insights into the earliest stages of epigenetic reprogramming by oncogenic transcription factors in AML.

cancer biology↗

Bio-inspired artificial printed bioelectronic cardio-3D-cellular constructs

Bioelectronics is a growing field where novel smart materials are required to interface biology with electronic components. Conductive hydrogels have recently emerged as a promising material for biosensing/actuating applications as they can provide a wet, nanostructured and electrically conductive environment, minimising the mismatch between biological and electronic systems. In this work, we propose a strategy to develop conductive bioinks compatible with the freeform reversible embedding of suspended hydrogels (FRESH) extrusion bioprinting method. These bioinks are based on decellularized extracellular matrix (dECM), extracted from three different tissues (small intestine submucosa, liver and bone) and were characterised. 3D structures were manufactured containing human pluripotent stem cell-derived cardiomyocytes (hPSC-CMs), exhibiting cell viabilities >80%. Multi-walled carbon nanotubes (MWCNTs) were selected as an additional component of the bioinks. The addition of the MWCNTs enhanced the conductive features of the hydrogels and the morphology of the dECM fibres. Electrical stimulation (ES) through alternating currents was applied to hPSC-CMs encapsulated in 3D structures manufactured with the previous material and our results indicated two main findings: (1) in the absence of external ES, the conductive properties of the materials can improve the contractile behaviour of the hPSC-CMs and (2) this effect is significantly enhanced under the application of external ES. Genetic markers analysed showed a trend towards a more mature state of the cells evaluated by the TNNI3/TNNI1 ratio, with upregulated SERCA2 and RYR2 calcium handling proteins when compared to controls and downregulation of calcium channels involved in the generation of pacemaking currents (CACNA1H). These results demonstrate the potential of our strategy to manufacture conductive hydrogels in complex geometries for bioactuating purposes. However, further development of the 3D bioprinting techniques is required to achieve higher control over the nano- and microarchitectures of the structures to improve their biomimicry.

bioengineering↗