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DiStasio, M.

Publications and source records attributed to DiStasio, M..

4 recordsLinked to original sources

Decoding Spatial Programs in Human Glioblastoma Through Surprisal Information-Theoretical Analysis

Glioblastoma (GBM) is a highly heterogeneous and invasive brain tumor in which complex interactions among tumor cells, immune cells, and neurons shape disease progression and therapeutic resistance. Resolving spatial patterns programs in glioblastoma (GBM) requires analytical approaches that go beyond variance-driven embeddings. Here, we applied thermodynamic surprisal analysis, an information-theoretic decomposition framework, to spatial transcriptomic sequencing from human GBM specimens to identify orthogonal constraint modes that capture dominant and previously hidden spatial programs. Surprisal analysis revealed structured patterns in the data that are not highlighted by standard approaches such as PCA or cell type deconvolution, including immune-activation-associated signatures as well as spatial programs consistent with synapse remodeling. Coupling surprisal decomposition with spatial ligand-receptor interaction analysis, NICHES, along with multiplexed protein imaging connected these spatial hidden modes to reveal potential communication networks. Together, these results position surprisal analysis as a powerful, complementary strategy for interrogating spatial tumor architecture, enabling discovery of non-obvious spatial programs and interactions that are obscured by variance-based methods.

systems biology↗

Mechanobiological Specialization of Choroid Plexus Macrophages Defined by Titin Expression

Functioning both as the site of cerebrospinal fluid production and as an interface between the peripheral circulation and the central nervous system, the choroid plexus (ChP) modulates the gating of immune cells and signals from the periphery as they pass from the blood into cerebrospinal fluid. We generated a single-nucleus and spatial transcriptomic atlas of the adult human ChP, in donors with and without Alzheimers disease (AD), revealing transcriptionally and spatially distinct macrophage states. We identified a previously unrecognized population of titin-expressing (TTN+) tissue-resident macrophages characterized by coordinated activation of cytoskeletal remodeling, phagocytosis, autophagy, and inflammatory programs. Isoform-specific qPCR, protein immunofluorescence, and single-molecule FISH validated TTN expression in situ. In AD, TTN+ macrophages expand and undergo broad transcriptional rewiring, including activation of MEF2-linked mechanotransduction pathways, elevated senescence signatures, and a loss of ligand-receptor connectivity with epithelial, endothelial, and stromal partners. Collectively, our findings define a mechanosensitive macrophage program at the blood-CSF interface and uncover a TTN-associated shift in macrophage function and microenvironment integration in AD.

neuroscience↗

Computer models predict differential dendritic vulnerability with ischemia and spreading depression

Ischemia, whether abrupt or chronic, limits ATP production and disrupts ATP-dependent homeostatic mechanisms, leading to alterations in both intracellular and extracellular ion concentrations. Inadequate neuronal ATP triggers K+ release and increased extracellular K+ depolarizes neurons, leading to additional K+ release; this positive feedback phenomenon is known as spreading depolarization (SD). When the depolarizing effects are strong enough, the cells undergo depolarization blockade, known as spreading depression. Excess extracellular K+ increases energy demand from the Na+-K+ pump, producing a pathological confluence of increased demand with reduced delivery of energy. The resulting changes have profound effects at subcellular, cellular, and network scales of brain function. We hypothesized that consequences of ischemic or SD homeostatic failure would differ on the subcellular scale, with differences between disjunct dendritic regions of a hippocampal CA1 pyramidal neuron. To evaluate the interplay between morphology and ion concentrations, we used a mechanistic simulation incorporating neuronal morphology, pumps, exchangers, voltage-, and Ca2+-sensitive ion channels. In both cases, calcium accumulation was greatest in the basilar dendrites, suggesting these dendrites would show the greatest effects of excitotoxicity. By contrast, ischemia, but not SD showed that distal apical dendrites were exposed to greater intracellular chloride concentrations, which may lead to dendritic beading.

neuroscience↗

Topological analysis of single-cell data reveals shared glial landscape of macular degeneration and neurodegenerative diseases

1One Sentence SummaryA novel topological machine learning approach applied to single-nucleus RNA sequencing from human retinas with age-related macular degeneration identifies interacting disease phase-specific glial activation states shared with Alzheimers disease and multiple sclerosis. 2 AbstractNeurodegeneration occurs in a wide range of diseases, including age-related macular degeneration (AMD), Alzheimers disease (AD), and multiple sclerosis (MS), each with distinct inciting events. To determine whether glial transcriptional states are shared across phases of degeneration, we sequenced 50,498 nuclei from the retinas of seven AMD patients and six healthy controls, generating the first single-cell transcriptomic atlas of AMD. We identified groupings of cells implicated in disease pathogenesis by applying a novel topologically-inspired machine learning approach called diffusion condensation. By calculating diffusion homology features and performing persistence analysis, diffusion condensation identified activated glial states enriched in the early phases of AMD, AD, and MS as well as an AMD-specific proangiogenic astrocyte state promoting pathogenic neovascularization in advanced AMD. Finally, by mapping the expression of disease-associated genes to glial states, we identified key signaling interactions creating hypotheses for therapeutic intervention. Our topological analysis identified an integrated disease-phase specific glial landscape that is shared across neurodegenerative conditions affecting the central nervous system.

neuroscience↗