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Biology subjects

Cooper, F.

Publications and source records attributed to Cooper, F..

5 recordsLinked to original sources

Functional and molecular rescue of aganglionic colon by human enteric nervous system progenitor transplantation in Hirschsprung disease

Hirschsprung disease (HSCR) is a devastating congenital disorder characterised by absence of the enteric nervous system (ENS) in the distal gut. Cell therapy, using human pluripotent stem cell-derived ENS progenitors, offers an attractive alternative to treat this life-limiting disorder. Here we provide an in-depth characterisation of the HSCR phenotype in the B6;129-Ednrbtm1Ywa/J mouse model including molecular analyses highlighting the wide-ranging molecular effects of aganglionosis in HSCR colon. We show that transplantation of hPSC-derived ENS progenitors leads to significant increases in contractile function with formation of extensive donor-derived neuronal networks in colonic explants. Moreover, post-transplantation, we show that integration of ENS progenitors rescues many of the biological pathways impacted in the HSCR aganglionic microenvironment. These novel results provide strong evidence that human ENS progenitor transplantation can modulate critical signalling pathways affected in HSCR and exert positive impacts on contractile function, in aganglionic tissue, supporting further translational development of this regenerative medicine approach.

cell biology↗

Open Benchmarking for Cell-Based Multiscale Models: Lessons from a Community Initiative

The emergence of virtual human twins (VHT) in biomedical research has sparked interest in multiscale in silico modelling frameworks, particularly in their application bridging cellular to tissue levels. Among the diverse array of multiscale modelling tools, off-lattice center-based agent-based models (CBM) offer a promising approach due to their depiction of cells in 3D space, closely resembling biological reality. Despite the proliferation of CBM tools addressing various biomedical challenges, a comprehensive and systematic comparison among them has been elusive. This paper presents a community-driven benchmark initiative aimed at evaluating and comparing CBM for biomedical applications, akin to successful efforts in other scientific domains such as the Critical Assessment of Protein Structure Prediction (CASP). Enlisting developers from leading tools like BioDynaMo, Chaste, PhysiCell,TiSim, and CompuTiX, we devised a benchmark scope, defined metrics, and established reference datasets to ensure a meaningful and equitable evaluation. Unit tests targeting different solvers within these tools were designed, ranging from diffusion and mechanics to cell cycle simulations and growth scenarios. Results from these tests demonstrate varying tool implementations in handling diffusion, mechanics, and cell cycle equations, emphasising the need for standardised benchmarks and interoperability. Discussions among the community underscore the necessity for defining gold standards, fostering interoperability, and drawing lessons from analogous benchmarking experiences. The outcomes, disseminated through a public platform in collaboration with OpenEBench, aim to catalyse advancements in computational biology, offering a comprehensive resource for tool evaluation and guiding future developments in cell-level simulations. This initiative endeavours to strengthen and expand the computational biology simulation community through continued dissemination and performance-oriented benchmarking efforts to enable the use of VHT in biomedicine.

systems biology↗

Zebrafish reveal new roles for Fam83f in hatching and the DNA damage-mediated autophagic response

The FAM83 (Family with sequence similarity 83) family is highly conserved in vertebrates, but little is known of the functions of these proteins beyond their association with oncogenesis. Of the family, FAM83F is of particular interest because it is the only membrane-targeted FAM83 protein. When over-expressed, FAM83F activates the canonical Wnt signalling pathway and binds to and stabilizes p53; it therefore interacts with two pathways often dysregulated in disease. Insights into gene function can often be gained by studying the roles they play during development, and here we report the generation of fam83f knock-out (KO) zebrafish, which we have used to study the role of Fam83f in vivo. We show that endogenous fam83f is most strongly expressed in the hatching gland of developing zebrafish embryos, and that fam83f KO embryos hatch earlier than their wild-type (WT) counterparts, despite developing at a comparable rate. We also demonstrate that fam83f KO embryos are more sensitive to ionizing radiation than WT embryos--an unexpected finding, bearing in mind the previously-reported ability of FAM83F to stabilize p53. Transcriptomic analysis shows that loss of fam83f leads to downregulation of phosphatidylinositol-3-phosphate (PI(3)P) binding proteins and impairment of cellular degradation pathways, particularly autophagy, a crucial component of the DNA damage response. Finally, we show that Fam83f protein is itself targeted to the lysosome when over-expressed in HEK293T cells, and that this localization is dependent upon a C terminal signal sequence. The zebrafish lines we have generated suggest that Fam83f plays an important role in autophagic/lysosomal processes, resulting in dysregulated hatching and increased sensitivity to genotoxic stress in vivo.

developmental biology↗

Notch signalling influences cell fate decisions and HOX gene induction in axial progenitors

The generation of the post-cranial embryonic body relies on the coordinated production of spinal cord neurectoderm and presomitic mesoderm cells from neuromesodermal progenitors (NMPs). This process is orchestrated by pro-neural and pro-mesodermal transcription factors that are co-expressed in NMPs together with Hox genes, which are critical for axial allocation of NMP derivatives. NMPs reside in a posterior growth region, which is marked by the expression of Wnt, FGF and Notch signalling components. While the importance of Wnt and FGF in influencing the induction and differentiation of NMPs is well established, the precise role of Notch remains unclear. Here, we show that the Wnt/FGF-driven induction of NMPs from human embryonic stem cells (hESCs) relies on Notch signalling. Using hESC-derived NMPs and chick embryo grafting, we demonstrate that Notch directs a pro-mesodermal character at the expense of neural fate. We show that Notch also contributes to activation of HOX gene expression in human NMPs, partly in a non cell-autonomous manner. Finally, we provide evidence that Notch exerts its effects via the establishment of a negative feedback loop with FGF signalling.

developmental biology↗

Rostrocaudal Patterning and Neural Crest Differentiation of Human Pre-Neural Spinal Cord Progenitors in vitro

The spinal cord emerges from a niche of neuromesodermal progenitors (NMPs) formed and maintained by Wnt/FGF signals at the posterior end of the embryo. NMPs can be generated from human pluripotent stem cells and hold promise for spinal cord replacement therapies. However, NMPs are transient, which complicates the full range production of rostrocaudal spinal cord identities in vitro. Here we report the generation of NMP-derived pre-neural progenitors (PNPs) with stem cell-like self-renewal capacity. PNPs maintain pre-spinal cord identity by co-expressing the transcription factors SOX2 and CDX2, and lose mesodermal potential by downregulating TBXT. For 7 to 10 passages PNPs divide to self-renew and to make trunk neural crest (NC), while gradually adopting a more posterior identity by activating colinear HOX gene expression. This HOX clock can be halted at the thoracic level for up to 30 passages by blocking the trunk-to-tail transition through GDF11-mediated signal inhibition.

developmental biology↗