Biology subjects

Stice, S. L.

Publications and source records attributed to Stice, S. L..

8 recordsLinked to original sources

bioRxiv2026

Serum neurofilament light chain predicts stroke outcome and is a potential marker for treatment effects of neural stem cell-derived extracellular vesicles in a rat stroke model

Acute ischemic stroke (AIS) remains a leading cause of disability worldwide, and effective treatments are urgently needed beyond reperfusion therapy. Translating preclinical success to clinical impact has been hindered by variability in animal models and the lack of translational biomarkers that predict outcomes across species. To overcome these barriers, we developed a robust rat AIS model optimized for consistency and severity, enabling rigorous therapeutic testing. Additionally, we tested a panel of common clinical serum biomarkers to improve translation from rodents to humans. We demonstrated that serum neurofilament light chain (NfL) -a biomarker widely used in clinical stroke studies-strongly correlated with functional outcomes, establishing a translational link that has not been previously reported in rats. Notably, NfLs predictive capabilities outperformed infarct volume, a key prognostic factor in moderate and severe strokes, as well as traditional serum biomarkers intercellular adhesion molecule-1 (ICAM-1) and S100 calcium binding protein (S100B). Using this platform, we evaluated the therapeutic impact of neural stem cell-derived extracellular vesicles (NSC EVs), a novel biologic therapy poised for clinical trials, on stroke outcome in our rat AIS model. A three-dose regimen of NSC EV over 48 hours produced the best outcomes in stroked animals evidenced by smaller infarct volume, improved neurologic score, and reduced serum NfL, although single-dose and two-dose regimens were both effective at some endpoints. These findings not only validate NfL as a cross-species biomarker but also provide critical dosing insights for NSC EV therapy, accelerating the path from bench to bedside for AIS treatment.

neuroscience↗

bioRxiv2025

Disrupting Akt-Wnt/β-catenin signaling suppresses glioblastoma stem cell growth and tumor progression in immunocompetent mice

Glioblastoma (GBM) is an aggressive primary malignant brain tumor in adults with a median patient survival of 12-18 months post-diagnosis. The PI3K/Akt and Wnt/{beta}-catenin signaling pathways promote GBM cell growth, survival, invasiveness and therapeutic resistance. We hypothesize that inhibiting Akt and {beta}-catenin, which are central regulatory proteins of the PI3K/Akt and Wnt/{beta}-catenin pathway, will suppress GBM growth and progression. Our in vitro studies demonstrate that MK-2206, a pan-Akt inhibitor, effectively reduced cell viability, induced apoptosis, and inhibited {beta}-catenin activity; consistently outperforming iCRT3, a {beta}-catenin-TCF interaction inhibitor, in CT-2A mouse glioma cells, and N08-30 human glioma stem cells. Luciferase-expressing CT-2A cells were then intracranially implanted in C57BL/6J mice followed by MK-2206 treatment, and we observed a reduction in phosphorylated Akt and GSK-3{beta} levels, consistent with disruption of the Akt and Wnt/{beta}-catenin signaling axis causing tumor suppression. In summary, MK-2206 outperformed iCRT3 efficacy in vitro, and suppressed GBM progression, in vivo. These findings suggest that Akt inhibition via MK-2206 may offer a promising therapeutic strategy for treating GBM characterized by dysregulation of PI3K/Akt or Wnt/{beta}-catenin pathways.

cancer biology↗

bioRxiv2023

Taste papilla cell differentiation requires tongue mesenchyme via ALK3-BMP signaling to regulate the production of secretory proteins

Taste papillae are specialized organs each of which is comprised of an epithelial wall hosting taste buds and a core of mesenchymal tissue. In the present study, we report that during the early stages of embryonic development, bone morphogenetic protein (BMP) signaling mediated by type 1 receptor ALK3 in the tongue mesenchyme is required for the epithelial Wnt/{beta}-catenin activity and taste papilla cell differentiation. Mesenchyme-specific knockout (cKO) of Alk3 using Wnt1-Cre and Sox10-Cre resulted in an absence of taste papillae at E12.0. Biochemical and cell differentiation analyses demonstrated that mesenchymal ALK3-BMP signaling governs the production of previously unappreciated secretory proteins, i.e., suppresses those that inhibiting and facilitates those promoting taste cell differentiation. Bulk RNA-Sequencing analysis revealed many more differentially expressed genes (DEGs) in the tongue epithelium than in the mesenchyme in Alk3 cKO vs control. Moreover, we detected a down-regulated epithelial Wnt/{beta}-catenin signaling, and taste papilla development in the Alk3 cKO was rescued by GSK3{beta} inhibitor LiCl, but not Wnt3a. Our findings demonstrate for the first time the requirement of tongue mesenchyme in taste papilla cell differentiation. Summary statementThis is the first set of data to implicate the requirement of tongue mesenchyme in taste papilla cell differentiation.

developmental biology↗

bioRxiv2023

Development of a Robust Consensus Modeling Approach for Identifying Cellular and Media Metabolites Predictive of Mesenchymal Stromal Cell Potency

Mesenchymal stromal cells (MSCs) have shown promise in regenerative medicine applications due in part to their ability to modulate immune cells. However, MSCs demonstrate significant functional heterogeneity in terms of their immunomodulatory function because of differences in MSC donor/tissue source, as well as non-standardized manufacturing approaches. As MSC metabolism plays a critical role in their ability to expand to therapeutic numbers ex vivo, we comprehensively profiled intracellular and extracellular metabolites throughout the expansion process to identify predictors of immunomodulatory function (T cell modulation and indoleamine-2,3-dehydrogenase (IDO) activity). Here, we profiled media metabolites in a non-destructive manner through daily sampling and nuclear magnetic resonance (NMR), as well as MSC intracellular metabolites at the end of expansion using mass spectrometry (MS). Using a robust consensus machine learning approach, we were able to identify panels of metabolites predictive of MSC immunomodulatory function for 10 independent MSC lines. This approach consisted of identifying metabolites in 2 or more machine learning models and then building consensus models based on these consensus metabolite panels. Consensus intracellular metabolites with high predictive value included multiple lipid classes (such as phosphatidylcholines, phosphatidylethanolamines, and sphingomyelins) while consensus media metabolites included proline, phenylalanine, and pyruvate. Pathway enrichment identified metabolic pathways significantly associated with MSC function such as sphingolipid signaling and metabolism, arginine and proline metabolism, and autophagy. Overall, this work establishes a generalizable framework for identifying consensus predictive metabolites that predict MSC function, as well as guiding future MSC manufacturing efforts through identification of high potency MSC lines and metabolic engineering.

bioengineering↗

bioRxiv2021

Multi-omics characterization of mesenchymal stem/stromal cells for the identification of putative critical quality attributes

BackgroundMesenchymal stromal cells (MSCs) have shown great promise in the field of regenerative medicine as many studies have shown that MSCs possess immunomodulatory function. Despite this promise, no MSC therapies have been granted licensure from the FDA. This lack of successful clinical translation is due in part to MSC heterogeneity and a lack of critical quality attributes (CQAs). While MSC Indoleamine 2,3-dioxygnease (IDO) activity has been shown to correlate with MSC function, multiple CQAs may be needed to better predict MSC function. MethodsThree MSC lines (two bone marrow, one iPSC) were expanded to three passages. At the time of harvest for each passage, cell pellets were collected for nuclear magnetic resonance (NMR) and ultra-performance liquid chromatography mass spectrometry (UPLC-MS), and media was collected for cytokine profiling. Harvested cells were also cryopreserved for assessing function using T cell proliferation and IDO activity assays. Linear regression was performed on functional and multiomics data to reduce the number of important features, and partial least squares regression (PLSR) was used to obtain putative CQAs based on variable importance in projection (VIP) scores. ResultsSignificant functional heterogeneity (in terms of T cell suppression and IDO activity) was observed between the three MSC lines, as well as donor-dependent differences based on passage. Omics characterization revealed distinct differences between cell lines using principal component analysis (PCA). Cell lines separated along principal component 1 based on tissue source (bone marrow vs. iPSC-derived) for NMR, MS, and cytokine profiles. PLSR modeling of important features predicts MSC functional capacity with NMR (R2=0.86), MS (R2=0.83), cytokines (R2=0.70), and a combination of all features (R2=0.88). DiscussionThe work described here provides a platform for identifying putative CQAs for predicting MSC functional capacity using PLSR modeling that could be used as release criteria and guide future manufacturing strategies for MSCs and other cell therapies.

bioengineering↗

bioRxiv2020

Development of an objective index, neural activity score (NAS), reveals neural network ontogeny and treatment effects on microelectrode arrays

Microelectrode arrays (MEAs) are valuable tools for electrophysiological analysis at a cellular population level, providing assessment of neural network health and development. Analysis can be complex, however, requiring intensive processing of large high-dimensional data sets consisting of many activity parameters. As a result, valuable information is lost, as studies subjectively report relatively few metrics in the interest of simplicity and clarity. From a screening perspective, many groups report simple overall activity; we are more interested in culture health and changes in network connectivity that may not be evident from basic activity parameters. For example, general changes in overall firing rate - the most commonly reported parameter - provide no information on network development or burst character, which could change independently. Our goal was to develop a fast objective process to capture most, if not all, the valuable information gained when using MEAs in neural development and toxicity studies. We implemented principal component analysis (PCA) to reduce the high dimensionality of MEA data. Upon analysis, we found that the first principal component was strongly correlated to time, representing neural culture development; therefore, factor loadings were used to create a single index score - named neural activity score (NAS) - reflective of neural maturation. To validate this score, we applied it to studies analyzing various treatments. In all cases, NAS accurately recapitulated expected results, suggesting this method is viable. This approach may be improved with larger training data sets and can be shared with other researchers using MEAs to analyze complicated treatment effects and multicellular interactions. Author SummaryAnalyzing neural activity has important applications such as basic neuroscience research, understanding neurological diseases, drug development, and toxicity screening. Technology for recording neural activity continues to develop, producing large data sets that provide complex information about neuronal function. One specific technology, microelectrode arrays (MEAs), has recently given researchers the ability to record developing neural networks with potential to provide valuable insight into developmental processes and pathological conditions. However, the complex data generated by these systems can be challenging to analyze objectively and quantitatively, hindering the potential of MEAs, especially for high-throughput approaches, such as drug development and toxicity screening, which require quick, simple, and accurate quantification. Therefore, we have developed an index for simple quantification and evaluation of neural network maturation and the effects of perturbation. We present validation of our approach using several treatments and culture conditions, as well as a meta-analysis of toxicological screening data to compare our approach to current methods. In addition to providing a simple quantification method for neural network activity in various conditions, our method provides potential for improved results interpretation in toxicity screening and drug development.

neuroscience↗

bioRxiv2020

Priming of MSCs with inflammation-relevant signals affects extracellular vesicle biogenesis, surface markers, and modulation of T cell subsets

Although considerable evidence exists supporting the use of mesenchymal stromal cells (MSCs) for treating immune diseases, successful clinical translation has been challenging and has led researchers to investigate cell-free alternatives. MSC-derived extracellular vesicles (MSC-EVs) have been shown to mediate a significant portion of the observed therapeutic effect, including immunosuppression. MSCs have been shown to respond to different aspects of the injury microenvironment such as inflammatory cytokines and hypoxia, although acidosis has not been investigated and different conditions have not been assessed in terms of their effects on MSC-EV function. This study investigated the effects of acidosis, hypoxia, and inflammatory cytokine priming on MSCs and MSC-EVs. We cultured MSCs in the presence of acidosis, hypoxia, or inflammatory cytokines (Interferon-gamma and Tumor Necrosis Factor-alpha) and compared the characteristics of their EVs as well as their uptake by and suppression of different T cell subsets. MSCs showed a greater effect on suppressing activated CD4+ and CD8+ T cells than MSC-EVs. However, MSC-EVs from MSCs primed with acidosis increased CD4+ and CD8+ regulatory T cell frequency in vitro. This functional response was reflected by MSC-EV uptake. MSC-EVs from acidosis-primed MSCs were taken up by CD4+ and CD8+ regulatory T cells at a significantly higher level than MSC-EVs from control, hypoxic, and inflammatory cytokine groups. These data suggest that a simple low-cost alteration in MSC culture conditions, acidosis, can generate extracelluar vesicles that have a desirable influence on anti inflammatory T cell subtypes.

bioengineering↗

bioRxiv2018

Chronic Electrical Stimulation Promotes the Excitability and Plasticity of ESC-derived Neurons following Glutamate-induced Inhibition In vitro

Functional electrical stimulation (FES) is rapidly gaining traction as a therapeutic tool for mediating the repair and recovery of the injured central nervous system (CNS). However, the underlying mechanisms and impact of these stimulation paradigms at a molecular, cellular and network level remain largely unknown. In this study, we used embryonic stem cell (ESC)-derived neuron and glial cocultures to investigate network maturation following acute administration of L-glutamate, which is a known mediator of excitotoxicity following CNS injury. We then modulated network maturation using chronic low frequency stimulation (LFS) and direct current stimulation (DCS) protocols. We demonstrated that L-glutamate impaired the rate of maturation of ESC-derived neurons and glia immediately and over a week following acute treatment. The administration of chronic LFS and DCS protocols individually following L-glutamate infusion significantly promoted the excitability of neurons as well as network synchrony, while the combination of LFS/DCS did not. qRT-PCR analysis revealed that LFS and DCS alone significantly up-regulated the expression of excitability and plasticity-related transcripts encoding N-methyl-D-aspartate (NMDA) receptor subunit (NR2A), brain-derived neurotrophic factor (BDNF) and Ras-related protein (RAB3A). In contrast, the simultaneous administration of LFS/DCS down-regulated BDNF and RAB3A expression. Our results demonstrate that LFS and DCS stimulation can modulate network maturation excitability and synchrony following the acute administration of an inhibitory dose of L-glutamate, as well as an upregulation of NR2A, BDNF and RAB3A gene expression. Our study also provides a novel framework for investigating the effects of electrical stimulation on neuronal responses and network formation/repair after traumatic brain injury.

neuroscience↗