Alzheimer's disease (AD) is the leading cause of dementia in older adults. Although AD progression is characterized by stereotyped accumulation of proteinopathies, the affected cellular populations remain understudied. Here we use multiomics, spatial genomics and reference atlases from the BRAIN Initiative to study middle temporal gyrus cell types in 84 donors with varying AD pathologies.
View Article and Find Full Text PDFAlzheimer's disease (AD) is the most common cause of dementia in older adults. Neuropathological and imaging studies have demonstrated a progressive and stereotyped accumulation of protein aggregates, but the underlying molecular and cellular mechanisms driving AD progression and vulnerable cell populations affected by disease remain coarsely understood. The current study harnesses single cell and spatial genomics tools and knowledge from the BRAIN Initiative Cell Census Network to understand the impact of disease progression on middle temporal gyrus cell types.
View Article and Find Full Text PDFDevelopmental processes underlying normal tissue regeneration have been implicated in cancer, but the degree of their enactment during tumor progression and under the selective pressures of immune surveillance, remain unknown. Here we show that human primary lung adenocarcinomas are characterized by the emergence of regenerative cell types, typically seen in response to lung injury, and by striking infidelity among transcription factors specifying most alveolar and bronchial epithelial lineages. In contrast, metastases are enriched for key endoderm and lung-specifying transcription factors, SOX2 and SOX9, and recapitulate more primitive transcriptional programs spanning stem-like to regenerative pulmonary epithelial progenitor states.
View Article and Find Full Text PDFKnowledge of immune cell phenotypes in the tumor microenvironment is essential for understanding mechanisms of cancer progression and immunotherapy response. We profiled 45,000 immune cells from eight breast carcinomas, as well as matched normal breast tissue, blood, and lymph nodes, using single-cell RNA-seq. We developed a preprocessing pipeline, SEQC, and a Bayesian clustering and normalization method, Biscuit, to address computational challenges inherent to single-cell data.
View Article and Find Full Text PDFSingle-cell RNA sequencing technologies suffer from many sources of technical noise, including under-sampling of mRNA molecules, often termed "dropout," which can severely obscure important gene-gene relationships. To address this, we developed MAGIC (Markov affinity-based graph imputation of cells), a method that shares information across similar cells, via data diffusion, to denoise the cell count matrix and fill in missing transcripts. We validate MAGIC on several biological systems and find it effective at recovering gene-gene relationships and additional structures.
View Article and Find Full Text PDFTo investigate mechanisms in outbred animals that increase the propensity to consume ethanol, it is important to identify and characterize these animals before or at early stages in their exposure to ethanol. In the present study, different measures were examined in adult Sprague-Dawley rats to determine whether they can predict long-term propensity to overconsume ethanol. Before consuming 9% ethanol with a two-bottle choice paradigm, rats were examined with the commonly used behavioral measures of novelty-induced locomotor activity and anxiety, as assessed during 15 min in an open-field activity chamber.
View Article and Find Full Text PDFAlcohol Clin Exp Res
February 2010
Background: Specialized hypothalamic systems that increase food intake might also increase ethanol intake. To test this possibility, morphine and receptor-specific opioid agonists were microinjected in the paraventricular nucleus (PVN) of rats that had learned to drink ethanol. To cross-validate the results, naloxone methiodide (m-naloxone), an opioid antagonist, was microinjected with the expectation that it would have the opposite effect of morphine and the specific opioid agonists.
View Article and Find Full Text PDFThe nucleus accumbens (NAc) participates in the control of both motivation and addiction. To test the possibility that opioids in the NAc can cause rats to select ethanol in preference to food, Sprague-Dawley rats with ethanol, food, and water available, were injected with two doses each of morphine, the mu-receptor agonist [D-Ala(2),N-Me-Phe(4),Gly(5)-ol]-Enkephalin (DAMGO), the delta-receptor agonist D-Ala-Gly-Phe-Met-NH2 (DALA), the k-receptor agonist (+/-)-trans-U-50488 methanesulfonate (U-50,488H), or the opioid antagonist naloxone methiodide (m-naloxone). As an anatomical control for drug reflux, injections were also made 2mm above the NAc.
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