Biology subjects

Rich-Griffin, C.

Publications and source records attributed to Rich-Griffin, C..

7 recordsLinked to original sources

bioRxiv2023

hadge: a comprehensive pipeline for donor deconvolution in single cell

Single cell multiplexing techniques (cell hashing and genetic multiplexing) allow to combine multiple samples, thereby optimizing sample processing and reducing batch effects. Cell hashing conjugates antibody-tags or chemical-oligonucleotides to cell membranes, while genetic multiplexing allows to mix genetically diverse samples and relies on aggregation of RNA reads at known genomic coordinates. We developed hadge (hashing deconvolution combined with genotype information), a Nextflow pipeline that combines 12 methods to perform both hashing- and genotype-based deconvolution. We propose a joint deconvolution strategy combining the best performing methods and we demonstrate how this approach leads to recovery of previously discarded cells in a nuclei hashing of fresh-frozen brain tissue.

bioinformatics↗

bioRxiv2023

A longitudinal single-cell therapeutic atlas of anti-tumour necrosis factor treatment in inflammatory bowel disease

Precision medicine in immune-mediated inflammatory diseases (IMIDs) requires an understanding of how cellular networks change following therapy. We describe a therapeutic atlas for Crohns disease (CD) and ulcerative colitis (UC) following anti-tumour necrosis factor (TNF) therapy. We generated ~1 million single-cell transcriptomes, organised into 109 cell states, from 216 gut biopsies from 38 patients and three controls, revealing disease- and therapy-specific differences. A systems-biology analysis identified distinct spatially-resolved cellular microenvironments: granuloma signatures in CD and interferon (IFN)-response signatures localising to T-cell aggregates and epithelial damage in CD and UC. Longitudinal comparisons demonstrated that disease progression in non-responders associated with myeloid and stromal cell perturbations in CD and increased multi-cellular IFN signalling in UC. IFN signalling was also observed in rheumatoid arthritis (RA) synovium with a lymphoid pathotype. Our therapeutic atlas informs drug positioning across IMIDs, and suggests a rationale for the use of janus kinase (JAK) inhibition following anti-TNF resistance.

immunology↗

bioRxiv2023

Panpipes: a pipeline for multiomic single-cell data analysis.

Single-cell multiomic analysis of the epigenome, transcriptome and proteome allows for comprehensive characterisation of the molecular circuitry that underpins cell identity and state. However, the holistic interpretation of such datasets presents a challenge given a paucity of approaches for systematic, joint evaluation of different modalities. Here, we present Panpipes, a set of computational workflows designed to automate multimodal single-cell and spatial transcriptomic analyses by incorporating widely-used Python-based tools to perform quality control, preprocessing, integration, clustering, and reference mapping at scale. Panpipes allows reliable and customisable analysis and evaluation of individual and integrated modalities, thereby empowering decision-making before downstream investigations.

bioinformatics↗

bioRxiv2022

Anti-TNF-induced IL-27 modulates regulatory T cell responses in patients with IBD that respond to therapy

Withdrawal statementThe authors have withdrawn their manuscript owing to failure to repeat some of the findings. Therefore, the authors do not wish this work to be cited as reference for the project. If you have any questions, please contact the corresponding author.

immunology↗

bioRxiv2022

Biochemical and metabolic maladaption defines pathological niches in progressive multiple sclerosis

Progressive multiple sclerosis (MS) is driven by demyelination, neuroaxonal loss, and mitochondrial damage occurring behind a closed blood-brain barrier (BBB).1,2 Patients with progressive MS typically fail to respond to available immunomodulatory drugs that reduce relapses in early disease.2 This indicates a dire need to identify non-canonical therapeutic avenues to limit neurodegeneration and promote protection and repair.3 Here, we have employed high-resolution multiomic profiling to characterise the biochemical and metabolic adaptations underpinning MS pathology, as these have been incompletely described but critically, may be amenable to BBB-permeable drug targeting. Using synchrotron radiation (SR)- and focal plane array (FPA)-based Fourier transform infrared microspectroscopy (FTIR), we spatially mapped the biochemical features present in human progressive MS and control post-mortem brain and rare spinal cord tissue. By employing single-nuclear RNA sequencing (snRNA-seq), 10x Genomics Visium spatial transcriptomics and spatial proteomics to resolve their cellular context, we found that these biochemical features provide a uniquely and highly disease-specific barcode for distinct pathological niches within the tissue. Characterisation of the metabolic processes underpinning these niches revealed an associated re-organisation of the astrocytic landscape in the grey and white matter, with implications for the treatment of progressive MS.

neuroscience↗

bioRxiv2022

Photizo: an open-source library for cross-sample analysis of FTIR spectroscopy data

With continually improved instrumentation, Fourier transform infrared (FTIR) microspectroscopy can now be used to capture thousands of high-resolution spectra for chemical characterisation of a sample. The spatially resolved nature of this method lends itself well to histological characterisation of complex biological specimens. However, commercial software currently available can make joint analysis of multiple samples challenging and, for large datasets, computationally infeasible. In order to overcome these limitations, we have developed Photizo - an open-source Python library for spectral analysis which includes functions for pre-processing, visualisation and downstream analysis, including principal component analysis, clustering, macromolecular quantification and biochemical mapping. This library can be used for analysis of spectroscopy data without a spatial component, as well as spatially-resolved data, such as data obtained via infrared (IR) microspectroscopy in scanning mode and IR imaging by focal plane array (FPA) detector. Contactcdendrou@well.ox.ac.uk

bioinformatics↗

bioRxiv2021

The plant circadian clock gene LHY influences Medicago truncatula nodulation

Legumes house nitrogen-fixing endosymbiotic rhizobia in specialized polyploid cells within root nodules, which are factories of metabolic activity. We discovered that the circadian clock-associated transcriptional factor LATE ELONGATED HYPOCOTYL (LHY) affects nodulation in Medicago truncatula. By carrying out expression analysis of transcripts over time in nodules we found that the clock enables coordinated control of metabolic and regulatory processes linked to nitrogen fixation. Rhythmic transcripts in root nodules include a subset of Nodule-specific Cysteine Rich peptides (NCRs) that have the LHY-bound conserved Evening Element in their promoters. Until now, studies have suggested that NCRs act to regulate bacteroid differentiation and keep the rhizobial population in check. However, these conclusions came from the study of a few members of this very large gene family that has complex diversified spatio-temporal expression. We suggest that rhythmic expression of NCRs may be important for temporal coordination of bacterial activity with the rhythms of the plant host, in order to ensure optimal symbiosis. HighlightsO_LIThe circadian clock-associated transcriptional factor LATE ELONGATED HYPOCOTYL (LHY) impacts on successful Medicago truncatula-rhizobial symbiosis C_LIO_LIThe plant clock coordinates rhythmic patterns of metabolic and regulatory activity in nodules and drives rhythmic expression of a subset of Nodule-specific Cysteine Rich (NCR) genes. C_LIO_LIRhythmic expression of NCRs may be important for temporal coordination of bacterial activity with plant host rhythms to ensure optimal symbiosis. C_LI

plant biology↗