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Heller, D. A.

Publications and source records attributed to Heller, D. A..

8 recordsLinked to original sources

Senescence-directed nanotherapy ameliorates fibrosis and overcomes immune exclusion in cancer

Fibrotic remodeling of tissues and tumors establishes immunosuppressive microenvironments that drive organ dysfunction and, in cancer, limit response to immunotherapy. Senescent-like cells are conserved drivers of fibrosis and therapeutic targets, yet their functional heterogeneity complicates therapeutic intervention. Here, we show that P-selectin is expressed by a subset of senescent-like cells in fibrotic tissues and tumors. Leveraging fucoidan-based nanoparticles that bind P-selectin, we developed senescence-modulating nanoparticles (SMNPs) to selectively target these disease-associated states. SMNPs exerted potent antifibrotic and immunomodulatory effects while improving therapeutic index. Mechanistically, we identified a pathogenic, immunosuppressive macrophage population as a functional target in vivo. In fibrotic tumors, niche remodeling restored immune infiltration and sensitized tumors to immune-checkpoint-based therapies. These findings establish SMNPs as a generalizable strategy to target pathogenic senescent cell subsets across fibrosis and cancer.

cancer biology↗

Galectin-3 is a Nanotherapeutic Target in Graft-versus-Host Disease Mediated Kidney Injury

Kidney injury is a frequent and serious complication of allogeneic hematopoietic cell transplantation (HCT), yet its pathophysiology remains poorly understood and effective treatments are lacking. Through analysis of kidney tissue from HCT recipients, we identified substantial acute tubular injury and T cell infiltration that correlated with extra-renal graft-versus-host disease (GVHD) severity, linking systemic alloreactivity and post-transplant renal pathology. In murine models, GVHD was similarly associated with acute kidney injury, renal Th1-type T cell infiltration, and hyperactivation of NF-{kappa}B and JAK-STAT signalling. Notably, galectin-3, a damage-associated lectin, was upregulated in both patient biopsies and experimental GVHD target organs. Leveraging this pathological feature, we engineered galectin-3-targeted lipid nanoparticles for tissue-specific delivery of ruxolitinib, an approved GVHD therapy. Galectin-3 upregulation was also identified in canonical acute GVHD target organs including the liver and intestinal tract, and nanoparticle-delivered ruxolitinib substantially enhanced renal function, reduced systemic GVHD, and minimized hematologic toxicity compared to conventional drug administration. Our findings demonstrate renal involvement in acute GVHD and establish a nanoparticle-based strategy for precision delivery of immunomodulatory therapies to affected tissues.

bioengineering↗

Preclinical shortwave infrared tumor screening and resection via pHLIP ICG under ambient lighting conditions

There is a critical need to improve optical imaging that will lead to its widespread acceptance for routine clinical procedures. Shortwave infrared (SWIR, 900-1700nm) imaging has demonstrated clear advantages over visible and near-infrared imaging (reduced autofluorescence with improved contrast, resolution, and sensitivity at tissue depth). Here we show that the previously reported compound, pH low insertion peptide (pHLIP) conjugated to indocyanine green (ICG, pHLIP ICG) currently in clinical trials, serves as an excellent candidate for SWIR imaging protocols. SWIRs increased sensitivity enabled preclinical tumor screening and resection at exposure times as low as 0.1 ms with acceptable signal-to-noise and contrast-to-noise ratios. Imaging was performed under ambient lighting conditions, and SWIRs sensitivity enabled an extended surgical resection window up to 96 hrs post injection in an orthotopic breast cancer mouse model. This work provides a direct precedent for the clinical translation of SWIR pHLIP ICG imaging for cancer resection. One Sentence SummarySWIR imaging under ambient lighting is highly sensitive to pHLIP ICG, a cancer targeting fluorescent agent currently under clinical investigation.

cancer biology↗

Hyperspectral Counting of Multiplexed Nanoparticle Emitters in Single Cells and Organelles

Nanomaterials are the subject of a range of biomedical, commercial, and environmental investigations involving measurements in living cells and tissues. Accurate quantification of nanomaterials, at the tissue, cell, and organelle levels, is often difficult, however, in part due to their inhomogeneity. Here, we propose a method that uses the diverse optical properties of a nanomaterial preparation in order to improve quantification at the single-cell and organelle level. We developed hyperspectral counting, which employs diffraction-limited imaging via hyperspectral microscopy of a diverse set of nanomaterial emitters, to estimate nanomaterial counts in live cells and sub-cellular structures. A mathematical model was developed, and Monte Carlo simulations were employed, to improve the accuracy of these estimates, enabling quantification with single-cell and single-endosome resolution. We applied this nanometrology technique to identify an upper-limit of the rate of uptake into cells - approximately 3,000 particles endocytosed within 30 minutes. In contrast, conventional ROI counting results in a 230% undercount. The method identified significant heterogeneity and a broad non-Gaussian distribution of carbon nanotube uptake within cells. For example, while a particular cell contained an average of 1 nanotube per endosome, the heterogenous distribution resulted in over 7 nanotubes localizing within some endosomes, substantially changing the accounting of subcellular nanoparticle concentration distributions. This work presents a method to quantify cellular and subcellular concentrations of a heterogeneous carbon nanotube reference material, with implications for nanotoxicology, drug/gene delivery, and nanosensor fields.

bioengineering↗

Machine-Perception Nanosensor Platform to Detect Cancer Biomarkers

Conventional molecular recognition elements, such as antibodies, present issues for the development of biomolecular assays for use in point-of-care devices, implantable/wearables, and under-resourced settings. Additionally, antibody development and use, especially for highly multiplexed applications, can be slow and costly. We developed a perception-based platform based on an optical nanosensor array that leverages machine learning algorithms to detect multiple protein biomarkers in biofluids. We demonstrated this platform in gynecologic cancers, which are often diagnosed at advanced stages, leading to low survival rates. We investigated the platform for detection in uterine lavage samples, which are enriched with cancer biomarkers compared to blood. We found that the method enables the simultaneous detection of multiple biomarkers in patient samples, with F1-scores of ~0.95 in uterine lavage samples from cancer patients. This work demonstrates the potential of perception-based systems for the development of multiplexed sensors of disease biomarkers without the need for specific molecular recognition elements.

bioengineering↗

Edaravone-Loaded Mesoscale Nanoparticles Treat Cisplatin-Induced Acute Kidney Injury

Cisplatin-induced acute kidney injury (CI-AKI) is a significant co-morbidity of chemotherapeutic regimens. While this condition is associated with substantially lower survival and increased economic burden, there is no pharmacological agent to effectively treat CI-AKI. The disease is hallmarked by acute tubular necrosis of the proximal tubular epithelial cells primarily due to increased oxidative stress. In our prior work, we developed a highly-selective kidney-targeted mesoscale nanoparticle (MNP) that accumulates primarily in the renal proximal tubular epithelial cells while exhibiting no toxicity. Here, we found that MNPs exhibit renal-selective targeting in multiple mouse models of tumor growth with virtually no tumor accumulation. We then evaluated the therapeutic efficacy of MNPs loaded with the reactive oxygen species scavenger edaravone in a mouse model of CI-AKI. We found a marked and significant therapeutic effect with this approach as compared to free drug or empty control MNPs, including improved renal function, histology, and diminution of oxidative stress. These results indicated that renal-selective MNP edaravone delivery holds substantial potential in the treatment of acute kidney injury among patients undergoing cisplatin-based chemotherapy.

bioengineering↗

Long-Term In Vivo Biocompatibility of Single-Walled Carbon Nanotubes

Over the past two decades, measurements of carbon nanotube toxicity and biodistribution have yielded a wide range of results. Properties such as nanotube type (single-walled vs. multi-walled), purity, length, aggregation state, and functionalization, as well as route of administration, greatly affect both the biocompatibility and biodistribution of carbon nanotubes. These differences suggest that generalizable conclusions may be elusive and that studies must be material- and application-specific. Here, we assess the short- and long-term biodistribution and biocompatibility of a single-chirality DNA-encapsulated single-walled carbon nanotube complex upon intravenous administration that was previously shown to function as an in-vivo reporter of endolysosomal lipid accumulation. Regarding biodistribution and fate, we found bulk specificity to the liver and >90% signal attenuation by 14 days in mice. Using near-infrared hyperspectral microscopy to measure single nanotubes, we found low-level, long-term persistence in organs such as the heart, liver, lung, kidney, and spleen. Measurements of histology, animal weight, complete blood count, and biomarkers of organ function all suggest short- and long-term biocompatibility. This work suggests that carbon nanotubes can be used as preclinical research tools in-vivo without affecting acute or long-term health.

bioengineering↗

A Carbon Nanotube Optical Reporter Maps Endolysosomal Lipid Flux

Lipid accumulation within the lumen of endolysosomal vesicles is observed in various pathologies including atherosclerosis, liver disease, neurological disorders, lysosomal storage disorders, and cancer. Current methods cannot measure lipid flux specifically within the lysosomal lumen of live cells. We developed an optical reporter, composed of a photoluminescent carbon nanotube of a single chirality, which responds to lipid accumulation via modulation of the nanotubes optical bandgap. The engineered nanomaterial, composed of short-single stranded DNA and a single nanotube chirality, localizes exclusively to the lumen of endolysosomal organelles without adversely affecting cell viability or proliferation, or organelle morphology, integrity, or function. The emission wavelength of the reporter can be spatially resolved from within the endolysosomal lumen to generate quantitative maps of lipid content in live cells. Endolysosomal lipid accumulation in cell lines, an example of drug-induced phospholipidosis (DIPL), was observed for multiple drugs in macrophages, and measurements of patient-derived Niemann-Pick type C fibroblasts identified lipid accumulation and phenotypic reversal of this lysosomal storage disease. Single-cell measurements using the reporter discerned sub-cellular differences in equilibrium lipid content, illuminating significant intracellular heterogeneity among endolysosomal organelles of differentiating bone marrow-derived monocytes. Single-cell kinetics of lipoprotein-derived cholesterol accumulation within macrophages revealed rates that differed among cells by an order of magnitude. This carbon nanotube optical reporter of endolysosomal lipid content in live cells confers new capabilities for drug development processes and the investigation of lipid-linked diseases.

bioengineering↗