Biology subjects

Inns, J.

Publications and source records attributed to Inns, J..

6 recordsLinked to original sources

bioRxiv2026

Single-cell proteomics resolves major cell populations and protein-defined chondrocyte states in the adult human osteoarthritic joint

Objective Single-cell RNA sequencing has transformed our understanding of cellular heterogeneity within osteoarthritic (OA) joint tissues, yet transcript abundance provides only an indirect measure of cellular phenotype and function. Recent advances in mass spectrometry now enable proteins to be measured directly at single-cell resolution. Here, we applied single-cell proteomics (SCP) to primary human OA cartilage and synovium to determine whether cellular heterogeneity within the diseased joint can be resolved directly at the proteome level. Design Cartilage and synovium were obtained from patients undergoing total knee arthroplasty for OA. Low-input proteomic profiling was first performed to establish proteome depth from limited cell numbers and validate biologically relevant clustering. SCP was then applied to individual cells, followed by unsupervised clustering, differential protein abundance analysis and iterative biological annotation. Results Low-input proteomics identified 7,800 proteins from 1,000 cells while retaining tissue- and cell-associated biological differences. Across the SCP dataset, ~2,300 unique proteins were detected, resolving chondrocyte, synovial fibroblast and immune-cell populations that closely paralleled those previously defined by single-cell transcriptomics. Higher-resolution analysis distinguished lining and sublining fibroblasts, discrete immune populations and multiple protein-defined chondrocyte states. Conclusions SCP enables direct characterisation of cellular heterogeneity within the human OA joint at the level of the proteome. By independently recovering established cellular populations while revealing protein-defined chondrocyte states, our findings establish SCP as a powerful complement to single-cell transcriptomics and open a new route to investigating functional cellular states and disease mechanisms that cannot be inferred from RNA abundance alone.

genetics↗

bioRxiv2026

A Context-Aware Single-Cell Proteomics Analysis pipeline.

Single-cell proteomics (SCP) by mass spectrometry can now quantify hundreds to thousands of proteins per cell, but the field still lacks standardised analytical pipelines that accommodate the diversity of instruments, sample preparation workflows and biological contexts encountered in practice. Existing workflows, largely adapted from single-cell transcriptomics, do not account for the informative missingness, pervasive ambient protein contamination and limited feature space that distinguish proteomic from transcriptomic data. In addition, cell type annotation remains a manual bottleneck that is subjective, difficult to reproduce and hard to scale. Here we present an end-to-end pipeline that integrates adaptive quality control, entropy-guided iterative batch correction, multi-modal marker discovery that exploits detection patterns unique to proteomics, and context-aware annotation by large language models (LLMs) coupled to structured contradiction reasoning and orthogonal data-driven validation. Benchmarking on published single-cell proteomic datasets from developing human brain and glioblastoma-associated neutrophils revealed systematic LLM failure modes, including context-insensitive marker vocabulary and misinterpretation of phagocytic or lytic cell states. We addressed these errors using a three-round prompt architecture that combines general biological principles with auto-generated dataset-specific constraints. In held-out validation on a skin tumour dataset acquired, the pipeline showed high concordance with FACS-sorted ground truth. In the caerulein-injured pancreas, orthogonal immunohistochemistry further supported annotations of macrophage, stellate and immune populations. The pipeline is fully automated under fixed settings, and available as Context-Aware Single-Cell Proteomics Analysis (CASPA), providing SCP laboratories and facilities with a reproducible workflow that delivers interpretable, confidence-quantified annotations suitable for downstream expert review.

bioinformatics↗

bioRxiv2026

Democratised single cell proteomics uncovers tumor associated macrophage signature in CYLD cutaneous syndrome skin tumors

Single-cell proteomics (SCP) reveals cellular heterogeneity and biological insights inaccessible to bulk analysis. Existing limitations are cost, sample loss during processing, and accessibility to state-of-the-art instrumentation. We describe a label free SCP methodology in human tissue, combining fluorescence activated cell sorting (FACS), oil-immersion cell handling, mass-spectrometry, and neural-network derived spectral libraries which address these issues. We tested this methodology in a skin tumor syndrome, CYLD cutaneous syndrome (CCS), assessing tumor heterogeneity. Using a Bruker timsTOF HT platform we quantified > 4000 proteins, averaging [~]700 per cell, through a cost-effective pipeline without specialised liquid handling infrastructure. By utilising pre-existing bioinformatic tools from the scRNA-seq field we implemented a robust analysis methodology, discriminating between macrophages, dendritic cells and tumor keratinocytes, in an unbiased analysis of 419 CCS tumor cells. We validated the biological accuracy of cell annotations by cross referencing with each cells FACS markers. Furthermore, we identified a novel CCS tumor associated macrophage population which carried a tumor microenvironment remodelling signature. Our findings demonstrate an accessible SCP technology capable of yielding novel biological discoveries in clinical tissue. Graphical abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=86 SRC="FIGDIR/small/704354v1_ufig1.gif" ALT="Figure 1"> View larger version (33K): org.highwire.dtl.DTLVardef@6fe6a3org.highwire.dtl.DTLVardef@8f0ff9org.highwire.dtl.DTLVardef@61e037org.highwire.dtl.DTLVardef@1c76a43_HPS_FORMAT_FIGEXP M_FIG C_FIG IMPORTANTO_LIManuscripts submitted to Review Commons are peer reviewed in a journal-agnostic way. C_LIO_LIUpon transfer of the peer reviewed preprint to a journal, the referee reports will be available in full to the handling editor. C_LIO_LIThe identity of the referees will NOT be communicated to the authors unless the reviewers choose to sign their report. C_LIO_LIThe identity of the referee will be confidentially disclosed to any affiliate journals to which the manuscript is transferred. C_LI GUIDELINESO_LIFor reviewers: https://www.reviewcommons.org/reviewers C_LIO_LIFor authors: https://www.reviewcommons.org/authors C_LI CONTACTThe Review Commons office can be contacted directly at: office@reviewcommons.org

biochemistry↗

bioRxiv2025

Comparative ubiquitinomics of human skin reveals insulin receptor ubiquitination as a regulator of collagen secretion.

Ubiquitination is central to skin homeostasis and disease, however the cutaneous ubiquitinome remains poorly characterised. We investigated spatial patterns of ubiquitination in human skin, discovering specific ubiquitin linkages located within the hair follicle and epidermis. To create a comprehensive physiological profile of the ubiquitinated proteins within the skin, we profiled healthy skin and CYLD cutaneous syndrome (CCS) skin tumours through di-glycine remnant immunopurification proteomics, enabling identification of 1605 ubiquitin sites across 731 proteins. The healthy cutaneous ubiquitinome comprised substrate classes including keratins, S100 proteins and histones. Predictive upstream enzyme analysis ranked the most frequent E3 ligase as NEDD4, and the most frequent deubiquitinases included USP7 and CYLD. Analysis of the CCS tumor ubiquitinome, characterized by catalytically inactivated CYLD somatic mutations and prominent extracellular matrix (ECM) secretion, identified 251 differentially ubiquitinated sites compared to healthy skin. The CCS ubiquitinome was enriched for cell division and differentiation proteins, including predicted CYLD substrate insulin receptor (INSR). Secretome analysis of INSR knockdown CCS primary cells revealed reduced secretion of basement membrane proteins, particularly COL7A1. By defining how ubiquitination modulates pathophysiological ECM secretory output, our study highlights the ubiquitin post-translational system as a broader determinant of tissue architecture. Graphical abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=86 SRC="FIGDIR/small/691868v1_ufig1.gif" ALT="Figure 1"> View larger version (47K): org.highwire.dtl.DTLVardef@565e59org.highwire.dtl.DTLVardef@4c3084org.highwire.dtl.DTLVardef@52a43org.highwire.dtl.DTLVardef@11999d8_HPS_FORMAT_FIGEXP M_FIG C_FIG

cell biology↗

bioRxiv2025

Targeting non-canonical NF-κB signalling in CYLD cutaneous syndrome by selective inhibition of IκB kinase alpha.

CYLD cutaneous syndrome (CCS) skin tumors develop from puberty onwards, can number in the hundreds and progressively grow over time. CCS patients lack medical therapies and require repeated surgery to control tumor burden. CYLD loss of heterozygosity (LOH) drives tumor growth, and CCS tumors have previously been shown to demonstrate increased canonical NF-{kappa}B and Wnt signalling. Here, we demonstrate evidence of non-canonical NF-{kappa}B signalling in CCS tumor keratinocytes, with increased p100 to p52 processing and RelB protein expression compared to normal skin. Utilizing complementary transcriptomics and proteomics on patient derived CCS tumor cell fractions, we identify I{kappa}B kinase alpha (IKK) as a candidate target in the non-canonical NF-{kappa}B signalling pathway. A novel, highly selective, IKK inhibitor (SU1644) used in patient derived CCS tumor spheroid cultures demonstrated that IKK inhibition reduced tumor spheroid viability. These data provide the pre-clinical rationale for the assessment of topical IKK inhibitors as a novel preventative treatment for CCS. TeaserTopical IKK inhibition emerges as a potential therapy for CYLD cutaneous syndrome by targeting non-canonical NF-{kappa}B signalling Graphical abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=125 SRC="FIGDIR/small/635629v1_ufig1.gif" ALT="Figure 1"> View larger version (39K): org.highwire.dtl.DTLVardef@829218org.highwire.dtl.DTLVardef@459f5dorg.highwire.dtl.DTLVardef@e198f6org.highwire.dtl.DTLVardef@1015685_HPS_FORMAT_FIGEXP M_FIG C_FIG

cancer biology↗

bioRxiv2021

A MALDI-TOF assay identifies nilotinib as an inhibitor of inflammation in acute myeloid leukemia and multiple myeloma.

Inflammatory responses are important in cancer, particularly in the context of monocyte-rich aggressive myeloid neoplasm. We developed a label-free cellular phenotypic drug discovery assay to identify anti-inflammatory drugs in human monocytes derived from acute myeloid leukaemia (AML), by tracking several biological features ionizing from only 2,500 cells using matrix-assisted laser desorption/ionization-time of flight (MALDI-TOF) mass spectrometry. A proof-of-concept screen showed that the BCR-ABL inhibitor nilotinib, but not the structurally similar imatinib, blocks inflammatory responses. In order to identify the cellular (off-)targets of nilotinib, we performed thermal proteome profiling (TPP). Unlike imatinib, nilotinib and other later generation BCR-ABL inhibitors inhibit the p38-MK2/3 signalling axis which suppressed the expression of inflammatory cytokines, cell adhesion and innate immunity markers in activated human monocytes derived from AML. Thus, our study provides a tool for the discovery of new anti-inflammatory drugs, which could contribute to the treatment of inflammation in myeloid neoplasms and other diseases. Key PointsLabel-free cell-based assay identifies new anti-inflammatory drugs using MALDI-TOF MS. Nilotinib reduces inflammation by inhibition of MAPK14-MK2/3 signalling axis in AML.

cancer biology↗