Biology subjects

Prior, S. J.

Publications and source records attributed to Prior, S. J..

2 recordsLinked to original sources

bioRxiv2025

Rapid CE-MS with Real-Time Eco-AI Resolves Proteomic Heterogeneity Among Single Human Neutrophils

Single-cell proteomics by mass spectrometry is advancing rapidly, yet throughput and sensitivity remain limiting--particularly for small, protein-poor cell types such as neutrophils. As the most abundant circulating leukocytes in humans, neutrophils are central to immune defense and inflammation, but their proteomes comprehensive single-cell level characterization has only concurrently been reported1 and remains limited. Here, we introduce a rapid capillary electrophoresis-mass spectrometry (CE-MS) platform, which integrates electrophoresis-correlative real-time data acquisition with sub-7-minute separations and artificial intelligence (AI)-based data processing software to achieve deep, high-throughput profiling. Using single-cell-equivalent HeLa digests, the Rapid Eco-AI platform identified [~]1,350 proteins from 300 pg and [~]835 proteins from 75 pg of input-- approaching the complexity of a mammalian cell proteome. Applied to freshly isolated human neutrophils, the workflow identified 151 proteins from [~]2 pg of material, [~]3% of the total cell proteome. Analysis of 13 individual cells revealed marked functional heterogeneity across pathways of degranulation, neutrophil extracellular trap (NET) formation, chemotaxis, and innate immunity, with hierarchical clustering resolving at least four distinct proteomic subtypes. These results establish Rapid Eco-AI as a sensitive, scalable, and broadly applicable CE-MS approach for immune-cell phenotyping at single-cell and subcellular resolution, facilitating new research opportunities in systems immunology and clinical proteomics.

developmental biology↗

bioRxiv2025

Age and Sex-Specific Changes in Mitochondrial Quality Control in Skeletal and Cardiac Muscle

Skeletal and cardiac muscle mitochondria exist in a dynamic reticulum that is maintained by a balance of mitochondrial biogenesis, fusion, fission, and mitophagy. This balance is crucial for adequate ATP production, and alterations in skeletal muscle mitochondria have been implicated in aging-associated declines in mitochondrial function. We sought to determine whether age and biological sex affect mitochondrial content [Complex IV (CIV)], biogenesis (PGC-1[a]), fusion (MFN2, OPA1), fission (DRP1, FIS1), and mitophagy (Parkin, Pink1) markers in skeletal and cardiac muscle by assessing protein expression in tibialis anterior (TA) and ventricular tissue from 16 young ([≤]6 months) and 16 old ([≥]20 months) male and female Sprague-Dawley rats. In the TA, CIV expression was 40% lower in old vs. young rats (p<0.001), indicating lower mitochondrial content, and coincided with higher expression of Parkin (+4-fold, p<0.001). Further, MFN2 expression was higher (+2-fold, p<0.005) and Parkin was lower (-40%, p=0.014) in older rats. In cardiac muscle, mitochondrial content was maintained in old vs. young rats, and this occurred concomitantly with higher expression of both PGC-1[a] and Parkin. MFN2 and OPA1 expression were also 1.2-5-fold higher in older rats (p<0.05 for all). Largely, protein expression did not differ between male and female rats, with the exception of Pink1 and FIS1 expression in the TA. Collectively, older skeletal and cardiac muscle demonstrated higher expression of fusion and mitophagy proteins, which indicates age alters the balance of biogenesis, fission, fusion, and mitophagy. This may, in turn, affect the ability to provide ATP to these metabolically active tissues.

physiology↗