RESUMO
BACKGROUND: Autism involves early brain overgrowth and dysfunction, which is most strongly evident in the prefrontal cortex. As assessed on pathological analysis, an excess of neurons in the prefrontal cortex among children with autism signals a disturbance in prenatal development and may be concomitant with abnormal cell type and laminar development. METHODS: To systematically examine neocortical architecture during the early years after the onset of autism, we used RNA in situ hybridization with a panel of layer- and cell-type-specific molecular markers to phenotype cortical microstructure. We assayed markers for neurons and glia, along with genes that have been implicated in the risk of autism, in prefrontal, temporal, and occipital neocortical tissue from postmortem samples obtained from children with autism and unaffected children between the ages of 2 and 15 years. RESULTS: We observed focal patches of abnormal laminar cytoarchitecture and cortical disorganization of neurons, but not glia, in prefrontal and temporal cortical tissue from 10 of 11 children with autism and from 1 of 11 unaffected children. We observed heterogeneity between cases with respect to cell types that were most abnormal in the patches and the layers that were most affected by the pathological features. No cortical layer was uniformly spared, with the clearest signs of abnormal expression in layers 4 and 5. Three-dimensional reconstruction of layer markers confirmed the focal geometry and size of patches. CONCLUSIONS: In this small, explorative study, we found focal disruption of cortical laminar architecture in the cortexes of a majority of young children with autism. Our data support a probable dysregulation of layer formation and layer-specific neuronal differentiation at prenatal developmental stages. (Funded by the Simons Foundation and others.).
Assuntos
Transtorno Autístico/patologia , Neocórtex/ultraestrutura , Adolescente , Transtorno Autístico/genética , Biomarcadores/análise , Biomarcadores/metabolismo , Calbindina 1/genética , Contagem de Células , Criança , Pré-Escolar , Crioultramicrotomia , Nucleotídeo Cíclico Fosfodiesterase do Tipo 1/genética , Expressão Gênica , Humanos , Imageamento Tridimensional , Hibridização In Situ , Neocórtex/crescimento & desenvolvimento , Proteínas do Tecido Nervoso/genética , Proteínas de Neurofilamentos/genética , Neurogênese , Neurônios/patologia , Membro 2 do Grupo F da Subfamília 1 de Receptores Nucleares/genética , RNA/genéticaRESUMO
Increasing numbers of cell and gene therapies (CGTs) are emerging to treat and cure pediatric diseases. However, small market sizes limit the potential return on investment within the traditional biopharmaceutical drug development model, leading to a market failure. In this Perspective, we discuss major factors contributing to this failure, including high manufacturing costs, regulatory challenges, and licensing practices that do not incorporate pediatric development milestones, as well as potential solutions. We propose the creation of a new entity, the Pediatric Advanced Medicines Biotech, to lead late-stage development and commercialize pediatric CGTs outside the traditional biopharmaceutical model in the United States-where organized efforts to solve this problem have been lacking. The Pediatric Advanced Medicines Biotech would partner with the academic ecosystem, manufacture products in academic good manufacturing practice facilities and work closely with regulatory bodies, to ferry CGTs across the drug development 'valley of death' and, ultimately, increase access to lifesaving treatments for children in need.
Assuntos
Terapia Baseada em Transplante de Células e Tecidos , Terapia Genética , Humanos , Terapia Genética/legislação & jurisprudência , Criança , Estados Unidos , Pediatria , Acessibilidade aos Serviços de SaúdeRESUMO
Efficient and precise genome editing requires a fast, quantitative, and inexpensive assay to assess genotype following editing. Here, we present ICE (Inference of CRISPR Edits), which enables robust analysis of CRISPR edits using Sanger data. ICE proposes potential outcomes for editing with guide RNAs, and then determines which are supported by the data via regression. The ICE algorithm is robust and reproducible, and it can be used to analyze CRISPR experiments within days after transfection. We also confirm that ICE produces accurate estimates of editing outcomes across a variety of benchmarks, and within the context of other existing Sanger analysis tools. The ICE tool is free to use and open source, and offers several improvements over current analysis tools, such as batch analysis and support for a variety of editing conditions. It is available online at ice.synthego.com, and the source code is available at github.com/synthego-open/ice.
Assuntos
Repetições Palindrômicas Curtas Agrupadas e Regularmente Espaçadas , Edição de Genes , Sistemas CRISPR-Cas/genética , Repetições Palindrômicas Curtas Agrupadas e Regularmente Espaçadas/genética , RNA Guia de Cinetoplastídeos/genética , SoftwareRESUMO
Following introduction of CRISPR-Cas9 components into a cell, genome editing occurs unabated until degradation of its component nucleic acids and proteins by cellular processes. This uncontrolled reaction can lead to unintended consequences including off-target editing and chromosomal translocations. To address this, we develop a method for light-induced degradation of sgRNA termed CRISPRoff. Here we show that light-induced inactivation of ribonucleoprotein attenuates genome editing within cells and allows for titratable levels of editing efficiency and spatial patterning via selective illumination.
Assuntos
Sistemas CRISPR-Cas/genética , Edição de Genes/métodos , Luz , Estabilidade de RNA/efeitos da radiação , RNA Guia de Cinetoplastídeos/metabolismo , Sistemas CRISPR-Cas/efeitos da radiação , Linhagem Celular Tumoral , Quebras de DNA de Cadeia Dupla , Estudos de Viabilidade , Células HEK293 , Humanos , RNA Guia de Cinetoplastídeos/efeitos da radiação , Ribonucleoproteínas/metabolismo , Translocação GenéticaRESUMO
Interactions between the cerebral cortex, thalamus, and basal ganglia form the basis of cognitive information processing in the mammalian brain. Understanding the principles of neuroanatomical organization in these structures is critical to understanding the functions they perform and ultimately how the human brain works. We have manually distilled and synthesized hundreds of primate neuroanatomy facts into a single interactive visualization. The resulting picture represents the fundamental neuroanatomical blueprint upon which cognitive functions must be implemented. Within this framework we hypothesize and detail 7 functional circuits corresponding to psychological perspectives on the brain: consolidated long-term declarative memory, short-term declarative memory, working memory/information processing, behavioral memory selection, behavioral memory output, cognitive control, and cortical information flow regulation. Each circuit is described in terms of distinguishable neuronal groups including the cerebral isocortex (9 pyramidal neuronal groups), parahippocampal gyrus and hippocampus, thalamus (4 neuronal groups), basal ganglia (7 neuronal groups), metencephalon, basal forebrain, and other subcortical nuclei. We focus on neuroanatomy related to primate non-primary cortical systems to elucidate the basis underlying the distinct homotypical cognitive architecture. To display the breadth of this review, we introduce a novel method of integrating and presenting data in multiple independent visualizations: an interactive website (http://www.frontiersin.org/files/cognitiveconsilience/index.html) and standalone iPhone and iPad applications. With these tools we present a unique, annotated view of neuroanatomical consilience (integration of knowledge).