Biology subjects

Carney, R. P.

Publications and source records attributed to Carney, R. P..

6 recordsLinked to original sources

bioRxiv2025

A physiological microfluidic blood-brain-barrier model for in vitro study of nanoparticle trafficking and accumulation

Although the blood-brain barrier (BBB) restricts passage of most molecules, various naturally occurring and synthetic nanoparticles are nonetheless found within the brain parenchyma. To study the mechanisms underlying this phenomenon, we developed a microfluidic BBB model (mBBB) using human cerebral microvascular endothelial cells (HCMECs) in direct contact with primary human astrocytes and pericytes within a physiologically relevant extracellular matrix. The horizontal architecture enables high-resolution imaging across the full barrier interface and allows direct assessment of nanoparticle transport and accumulation. This in vitro platform recapitulates key features of the BBB, including selective permeability, junctional protein expression, and receptor-mediated uptake pathways. Using this system, the trafficking and accumulation of structurally distinct nanoparticles, including liposomes, nanoplastics, and extracellular vesicles (EVs), were compared. Among these, heterologous EVs exhibit the highest transport efficiency. Analysis of nanoparticle properties suggest that ligand presentation and membrane composition, rather than size or stiffness, primarily govern BBB penetration. The mBBB platform provides a high-throughput, imaging-based framework to systematically interrogate nanoparticle trafficking across the BBB and offers a translational tool for both drug delivery and neurotoxicity screening.

bioengineering↗

bioRxiv2025

Spatial and spectral mapping of traffic-related air pollution (TRAP) nanoparticles in relation to plaques and inflammatory markers in an Alzheimer disease model

Chronic exposure to traffic-related air pollution (TRAP) is linked to increased risk of neurodegenerative diseases, including Alzheimer disease (AD). Ultrafine particulate matter (UFPM) is a suspected driver of TRAP neurotoxicity, but its spatial interactions with AD pathology remain poorly defined. We investigated the distribution, composition, and pathological context of TRAP-derived UFPM in the hippocampus of TgF344-AD rats chronically exposed to TRAP or filtered air (FA) for 14 months. Using a multimodal imaging workflow that combines enhanced darkfield hyperspectral imaging (EDF-HSI) with confocal immunofluorescence for microglia (CD68/Iba1) and amyloid beta (A{beta}) plaques (Thioflavin S), we mapped the localization and spectral properties of UFPM in situ. UFPM accumulation was elevated in TRAP-exposed females, suggesting sex-specific vulnerability in blood-brain barrier (BBB) permeability or particle retention. Particles near plaques showed red-shifted spectral signatures, consistent with biochemical transformation. Dimension reduction revealed clustering of particle spectra by TRAP exposure and plaque proximity. However, UFPM was rarely found within plaques or microglia, implying indirect neuroimmune modulation. These findings highlight a novel spatial and spectral imaging approach for characterizing environmental nanoparticle interactions in the brain and suggest that chronic TRAP exposure may influence AD-related inflammation and pathology in a sex-and region-dependent manner. SynopsisThis study shows that chronic traffic-related air pollution alters ultrafine particulate matter deposition and neuroinflammation in a rodent Alzheimer model, revealing region- and sex-specific vulnerability in the brains response to environmental exposure.

pharmacology and toxicology↗

bioRxiv2024

Plasma-derived extracellular vesicles (EVs) as biomarkers of sepsis in burn patients via label-free Raman spectroscopy

Sepsis following burn trauma is a global complication with high mortality, with [~]60% of burn patient deaths resulting from infectious complications. Sepsis diagnosis is complicated by confounding clinical manifestations of the burn injury, and current biomarkers markers lack the sensitivity and specificity required for prompt treatment. Circulating extracellular vesicles (EVs) from patient liquid biopsy as biomarkers of sepsis due to their release by pathogens from bacterial biofilms and roles in subsequent immune response. This study applies Raman spectroscopy to patient plasma derived EVs for rapid, sensitive, and specific detection of sepsis in burn patients, achieving 97.5% sensitivity and 90.0% specificity. Furthermore, spectral differences between septic and non-septic burn patient EVs could be traced to specific glycoconjugates of bacterial strains associated with sepsis morbidity. This work illustrates the potential application of EVs as biomarkers in clinical burn trauma care, and establishes Raman analysis as a fast, label-free method to specifically identify features of bacterial EVs relevant to infection amongst the host background.

biophysics↗

bioRxiv2024

Post-death Vesicles of Senescent Bone Marrow Mesenchymal Stromal Polyploids Promote Macrophage Aging and Breast Cancer

Potential systemic factors contributing to aging-associated breast cancer (BC) remain elusive. Here, we reveal that the polyploid giant cells (PGCs) that contain more than two sets of genomes prevailing in aging and cancerous tissues constitute 5-10% of healthy female bone marrow mesenchymal stromal cells (fBMSCs). The PGCs can repair DNA damage and stimulate neighboring cells for clonal expansion. However, dying PGCs in advanced-senescent fBMSCs can form "spikings" which are then separated into membraned mtDNA-containing vesicles (Senescent PGC-Spiking Bodies; SPSBs). SPSB-phagocytosed macrophages accelerate aging with diminished clearance on BC cells and protumor M2 polarization. SPSB-carried mitochondrial OXPHOS components are enriched in BC of elder patients and associated with poor prognosis. SPSB-incorporated breast epithelial cells develop aggressive characteristics and PGCs resembling the polyploid giant cancer cells (PGCCs) in clonogenic BC cells and cancer tissues. These findings highlight an aging BMSC-induced BC risk mediated by SPSB-induced macrophage dysfunction and epithelial cell precancerous transition. SIGNIFICANCEMechanisms underlying aging-associated cancer risk remain unelucidated. This work demonstrates that polyploid giant cells (PGCs) in bone marrow mesenchymal stromal cells (BMSCs) from healthy female bone marrow donors can boost neighboring cell proliferation for clonal expansion. However, the dying-senescent PGCs in the advanced-senescent fBMSCs can form "spikings" which are separated into mitochondrial DNA (mtDNA)-containing spiking bodies (senescent PGC-spiking bodies; SPSBs). The SPSBs promote macrophage aging and breast epithelial cell protumorigenic transition and form polyploid giant cancer cells. These results demonstrate a new form of ghost message from dying-senescent BMSCs, that may serve as a systemic factor contributing to aging-associated immunosuppression and breast cancer risk. Graphic Abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=110 SRC="FIGDIR/small/583755v1_ufig1.gif" ALT="Figure 1"> View larger version (50K): org.highwire.dtl.DTLVardef@f07b60org.highwire.dtl.DTLVardef@33ef98org.highwire.dtl.DTLVardef@1b720c8org.highwire.dtl.DTLVardef@1c9514d_HPS_FORMAT_FIGEXP M_FIG Xie et al demonstrate that the polyploid giant cells (PGCs) in the juvenile phase expansion of female bone marrow mesenchymal stromal cells (fBMSCs) can boost neighboring cell proliferation for clonal expansion. However, when fBMSCs enter to the advanced-senescent phase, the dying-senescent PGCs form "spikings" which are then separated into membraned vesicles termed Senescent PGC spiking bodies, SPSBs). The SPSBs carrying fragmented mitochondrial elements and OXPHOS proteins can be phagocytosed by macrophage and breast epithelial cells leading to macrophage aging and breast epithelial protumorigenic transition. The SPSBs are demonstrated to be a new form of post-cell death vesicle from aging BMSCs and may serve as a systemic factor contributing to aging-associated immunosuppression and breast cancer risk. C_FIG

cancer biology↗

bioRxiv2022

Convection and extracellular matrix binding control interstitial transport of extracellular vesicles

Extracellular vesicles (EVs) influence a host of normal and pathophysiological processes in vivo. Compared to soluble mediators, EVs are relatively large (~30-150 nm) and can traffic a wide range of proteins on their surface including extracellular matrix (ECM) binding proteins. We isolated EVs from the MCF10 series - a model human cell line of breast cancer progression - and demonstrated increasing presence of laminin-binding integrins 3{beta}1 and 6{beta}1 on the EVs as the malignant potential of the MCF10 cells increased. Transport of the EVs within a microfluidic device under controlled physiological interstitial flow (0.15-0.75 m/s) demonstrated that convection was the dominant mechanism of transport. Binding of the EVs to the ECM enhanced the spatial concentration and gradient, which was partially mitigated by blocking integrins 3{beta}1 and 6{beta}1. Our studies demonstrate that convection and ECM binding are the dominant mechanisms controlling EV interstitial transport and should be leveraged in the design of nanotherapeutics.

bioengineering↗

bioRxiv2021

Tetraspanin immunocapture phenotypes extracellular vesicles according to biofluid source but may limit identification of multiplexed cancer biomarkers

Tetraspanin expression of extracellular vesicles (EVs) is often used as a surrogate for their general detection and classification from background contaminants. This common practice typically assumes a consistent expression of tetraspanins across EV sources, thus obscuring subpopulations of variable or limited tetraspanin expression. While some recent studies indicate differential expression of tetraspanins across bulk isolated EVs, here we present analysis of single EVs isolated using various field-standard methods from a variety of in vitro and in vivo sources to identify distinct patterns in colocalization of tetraspanin expression. We report an optimized method for the use of antibodycapture single particle interferometric reflectance imaging sensing (SP-IRIS) and fluorescence detection to identify subpopulations according to tetraspanin expression and compare our findings with nanoscale flow cytometry. Using SP-IRIS and immunofluorescence, we report that tetraspanin profile is consistent from a given EV source regardless of isolation method, but that tetraspanin profiles are distinct across various sources. Tetraspanin profiles as measured by flow cytometry do not share similar trends, suggesting that limitations in subpopulation detection significantly impact apparent protein expression. We further analyzed tetraspanin expression of single EVs captured non-specifically, revealing that tetraspanin capture can bias the apparent multiplexed tetraspanin profile. Finally, we demonstrate that this bias can have significant impact on diagnostic sensitivity for tumor-associated EV surface markers. Our findings may reveal key insights into the complexities of the EV biogenesis and signaling pathways and better inform EV capture and detection platforms for diagnostic or other downstream use.

molecular biology↗