Biology subjects

O'Connor, R. A.

Publications and source records attributed to O'Connor, R. A..

3 recordsLinked to original sources

bioRxiv2026

Therapeutic signature mapping of paired direct and indirect LPS injury in an ex vivo human lung perfusion platform reveals injury-specific druggable programs

Acute Respiratory Distress Syndrome (ARDS) remains highly morbid and lacks approved disease-modifying pharmacotherapies. Direct (pulmonary) and indirect (extrapulmonary) insults may initiate biologically distinct early injury programs, but human tissue-level evidence from the first hours is scarce. Here we establish a paired, acellular ex vivo lung perfusion (EVLP) platform using human donor lungs unsuitable for transplantation to model direct (endobronchial) and indirect (perfusate) lipopolysaccharide (LPS) injury within the same donor. We profiled lung tissue proteomes at 4 h post-insult and performed therapeutic nomination by querying proteomics-derived injury signatures against the CLUE L1000 perturbational compendium with independent cross-platform validation. Both models developed histological injury and robust cytokine release. Direct injury preferentially enriched neutrophil degranulation, extracellular matrix remodelling and metabolic reprogramming modules, whereas indirect injury showed prominent complement/coagulation perturbation with greater endothelial activation markers in perfusate. Cross-platform prioritisation converged on tractable signalling and epigenetic axes, including JAK/STAT, PI3K/AKT/mTOR, SYK, CDK and HDAC inhibitor classes - yielding a tiered shortlist for EVLP intervention testing. This intact human lung perturbation platform enables injury-stratified mechanistic inference and therapeutic prioritisation in early lung injury relevant to ARDS.

immunology↗

bioRxiv2026

Endomicroscopic fluorescence lifetime imaging enables molecular detection and targeted sampling in the distal human lung

PurposeAccurate molecular characterisation of infection and inflammation within the distal human lung remains challenging, particularly in critically ill patients, due to limited access to the alveolar space and delayed diagnostic workflows. Molecular imaging approaches capable of real-time detection and targeted sampling could substantially improve diagnostic precision and the future translational development of molecular imaging probes and therapeutics. MethodsIn a preclinical setting, we evaluated a clinic-ready endomicroscopic fluorescence lifetime imaging microscopy (eFLIM) platform combined with molecularly targeted SmartProbes for in situ detection of bacteria and activated neutrophils in the distal human lung. A multifunctional 1.9-mm diameter imaging and sampling catheter (Eyes on Target; EoT) enabled real-time fluorescence intensity and lifetime imaging alongside directed alveolar microlavage via a 1.2-mm working channel. Fluorescence intensity and lifetime signatures of Gram-negative bacteria, Gram-positive bacteria, and activated neutrophils were characterised using three wash-free SmartProbes: NBD-PMX, Merocy-Van, and a neutrophil activation probe (NAP). Imaging and sampling performance were assessed in ventilated ex vivo human lungs. ResultsEoT reliably navigated to alveolar regions across all lung lobes in both phantom and ventilated human lung models. eFLIM distinguished alveolar microanatomy and enabled probe-specific molecular detection within the distal lung. Increased NBD-PMX signal was detected in Escherichia coli-instilled lobes, while Merocy-Van lifetime signatures selectively identified Staphylococcus aureus-instilled regions. Activated neutrophils were detected throughout lung tissue following NAP administration. Directed alveolar microlavage enabled recovery of cellular material and bacterial DNA from imaged regions for downstream analysis. ConclusioneFLIM using EoT combined with molecular SmartProbes enables real-time molecular imaging and targeted sampling within the distal human lung. This platform provides a translatable approach for evaluating infection and inflammation at the alveolar level and supports the clinical development of molecular imaging probes for pulmonary disease.

microbiology↗

bioRxiv2022

Quantitative proteomics identifies tumour matrisome signatures in patients with non-small cell lung cancer

The composition and remodelling of the extracellular matrix (ECM) are important factors in the development and progression of cancers, and the ECM is implicated in promoting tumour growth and restricting anti-tumour therapies through multiple mechanisms. The characterisation of differences in ECM composition between normal and diseased tissues may aid in identifying novel diagnostic markers, prognostic indicators and therapeutic targets for drug development. Using tissue from non-small cell lung cancer (NSCLC) patients undergoing curative intent surgery, we characterised quantitative tumour-specific ECM proteome signatures by mass spectrometry, identifying 161 matrisome proteins differentially regulated between tumour tissue and nearby non-malignant lung tissue. We defined a collagen hydroxylation functional protein network that is enriched in the lung tumour microenvironment. We validated two novel putative extracellular markers of NSCLC, the collagen cross-linking enzyme peroxidasin and a disintegrin and metalloproteinase with thrombospondin motifs 16 (ADAMTS16), for discrimination of malignant and non-malignant lung tissue. These proteins were up-regulated in lung tumour samples, and high PXDN and ADAMTS16 gene expression was associated with shorter survival of lung adenocarcinoma and squamous cell carcinoma patients, respectively. These data reveal tumour matrisome signatures in human NSCLC. O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=19 SRC="FIGDIR/small/510064v1_ufig1.gif" ALT="Figure 1"> View larger version (8K): org.highwire.dtl.DTLVardef@b34045org.highwire.dtl.DTLVardef@40a5a9org.highwire.dtl.DTLVardef@3c150corg.highwire.dtl.DTLVardef@89c6f2_HPS_FORMAT_FIGEXP M_FIG C_FIG

cancer biology↗