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Wright, C. W.

Publications and source records attributed to Wright, C. W..

4 recordsLinked to original sources

Somatic mtDNA Mutation Burden Shapes Metabolic Plasticity in Leukemogenesis

The role of somatic mitochondrial DNA (mtDNA) mutations in leukemogenesis remains poorly characterized. To determine the impact of somatic mtDNA mutations on the process, we assessed the leukemogenic potential of hematopoietic progenitor cells (HPCs) from mtDNA mutator mice (Polg D257A) with or without NMyc overexpression. We observed a higher incidence of spontaneous leukemogenesis in recipients transplanted with heterozygous Polg HPCs and a lower incidence of NMyc-driven leukemia in those with homozygous Polg HPCs compared to controls. Although mtDNA mutations in heterozygous and homozygous HPCs caused similar baseline impairments in mitochondrial function, only heterozygous HPCs responded to and supported altered metabolic demands associated with NMyc overexpression. Homozygous HPCs showed altered glucose utilization with pyruvate dehydrogenase inhibition due to increased phosphorylation, exacerbated by NMyc overexpression. The impaired growth of NMyc-expressing homozygous HPCs was partially rescued by inhibiting pyruvate dehydrogenase kinase, highlighting a relationship between mtDNA mutation burden and metabolic plasticity in leukemogenesis. TEASERSomatic mtDNA mutations as drivers of metabolic change in the development of leukemia.

cancer biology↗

Development of a high-throughput barrier function assay using primary human gut organoids

Disruptions in the gut epithelial barrier can lead to the development of chronic indications such as inflammatory bowel disease (IBD). Historically, barrier function has been assessed in cancer cell lines, which do not contain all human intestinal cell types, leading to poor translatability. To bridge this gap, we adapted human primary gut organoids grown as monolayers to assess barrier function. In this work we describe and characterize a novel 96-well human gut organoid-derived monolayer system that enables medium/high-throughput quantitative assessment of candidate therapeutics. Normal human intestine differentiation patterns and barrier function were characterized and confirmed to recapitulate key aspects of in vivo biology. Next, cellular response to TNF- (a central driver of IBD) was determined using a diverse cadre of readouts.These outputs included transcription factor phosphorylation, target gene expression, cytokine/chemokine production, and barrier function. Additionally, we showed that TNF- pathway antagonists rescued damage caused by TNF- in a dose-dependent manner, indicating that this system is suitable for quantitative assessment of barrier modulating factors. Taken together, we have established a robust primary cell-based 96-well system capable of interrogating questions around mucosal response. This system is well suited to provide pivotal functional data to support translational target and drug discovery efforts.

immunology↗

Assessing donor-to-donor variability in human intestinal organoid cultures

Donor-to-donor variability in primary human organoid cultures has not been well characterized. As these cultures contain multiple cell types, there is greater concern that variability could lead to increased noise. In this work we investigated donor-to-donor variability in human gut adult stem cell (ASC) organoids. We examined intestinal developmental pathways during culture differentiation in ileum- and colon-derived cultures established from multiple donors, showing that differentiation patterns were consistent among cultures. This finding indicates that donor-to-donor variability in this system remains at a manageable level. Intestinal metabolic activity was evaluated by targeted analysis of central carbon metabolites and by analyzing hormone production patterns. Both experiments demonstrated similar metabolic functions among donors. Importantly, this activity reflected intestinal biology, indicating that these ASC organoid cultures are appropriate for studying metabolic processes. This work establishes a framework for generating high confidence data using human primary cultures through thorough characterization of variability.

developmental biology↗

Gut-Liver physiomimetics reveal paradoxical modulation of IBD-related inflammation by short-chain fatty acids

Association between the microbiome, IBD and liver diseases are known, yet cause and effect remain elusive. By connecting human microphysiological systems of the gut, liver and circulating Treg/Th17 cells, we modeled progression of ulcerative colitis (UC) ex vivo. We show that microbiome-derived short-chain fatty acids (SCFA) may either improve or worsen disease severity, depending on the activation state of CD4 T cells. Employing multiomics, we found SCFA increased production of ketone bodies, glycolysis and lipogenesis, while markedly reducing innate immune activation of the UC gut. However, during acute T cell-mediated inflammation, SCFA exacerbated CD4+ T cell effector function, partially through metabolic reprograming, leading to gut barrier disruption and hepatic injury. These paradoxical findings underscore the emerging utility of human physiomimetic technology in combination with systems immunology to study causality and the fundamental entanglement of immunity, metabolism and tissue homeostasis.\n\nO_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=87 SRC=\"FIGDIR/small/706812v2_ufig1.gif\" ALT=\"Figure 1\">\nView larger version (31K):\norg.highwire.dtl.DTLVardef@10006b0org.highwire.dtl.DTLVardef@b7344eorg.highwire.dtl.DTLVardef@1cb0c06org.highwire.dtl.DTLVardef@1826e38_HPS_FORMAT_FIGEXP M_FIG C_FIG

bioengineering↗