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Biology subjects

Holbrook, S.

Publications and source records attributed to Holbrook, S..

2 recordsLinked to original sources

Long-term high throughput agitation culturing with real-time metabolic profiling

Cellular metabolism relies on the dynamic coordination between glycolytic flux in the cytosol and oxidative phosphorylation (OXPHOS) within the mitochondria. To study the metabolic profiles of cells, researchers apply a monitoring system for measurements of critical parameters, e.g., pH and dissolved oxygen (DO), to understand underlying energy production tendencies, dictating the performance, resilience and growth of cells. However, implementing sensitive, non-invasive sensors into long-term culturing environments remains a technical bottleneck. Here, we describe the DolphinQ bioanalyzer, a novel culturing platform designed for high-throughput, real-time monitoring of cellular metabolism states under physiologically relevant conditions. We validate the system across multiple cell types and experimental set-ups, demonstrating its ability to resolve subtle metabolic shifts that are typically obscured in end-point assays. Notably, we utilize the system to characterize the metabolic impact of heteroplasmy in a mitochondrial disease model with affected ATP synthase. Our results underscore the utility of continuous, minimally disruptive monitoring for revealing the complexities of cellular metabolic adaptation. The DolphinQ framework therefore offers a robust tool for optimizing culture conditions across a wide range of applications and advancing fundamental research into metabolic flux and mitochondrial dysfunction.

bioengineering↗

Efficient Cas9 nuclease-based editing in skeletal muscle via lipid nanoparticle delivery

Gene editing holds great promise for muscular dystrophy treatment, but the rapid evaluation of different editing modalities in skeletal muscle in vivo remains challenging due to lack of simple, effective delivery tools. Here we demonstrate that selective organ targeting (SORT) lipid nanoparticles (LNP) encapsulating optimized Cas9 cargo can facilitate efficient, local delivery to skeletal muscles achieving editing rates [≥]35% and restore protein expression for a proof-of-concept muscular dystrophy target. Interestingly, efficient editing in skeletal muscle was observed despite a strong adaptive immune response to repeat dosing of the Cas9 LNPs. High efficiency editing mediated by LNP-based delivery of Cas9 to skeletal muscle permitted detailed analysis of insertion and deletion (InDel) outcomes in vivo for a set of potential therapeutic target sites, which differed substantially from InDel outcomes observed in proliferating cells in one specific instance. Overall, our findings on enhanced LNP delivery of Cas9, platform-specific immune responses, and differential editing patterns observed between in vitro and in vivo models provide valuable insights that should inform the development of gene editing therapeutics for neuromuscular diseases. One Sentence SummarySORT LNPs permitted efficient Cas9-mediated repair of a pathogenic allele in skeletal muscle in a mouse model of LGMDR7.

molecular biology↗