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Muotri, A.

Publications and source records attributed to Muotri, A..

5 recordsLinked to original sources

Brain Organoids, Lessons from Fetal Neocortex Formation, and Rational Design for Quality Control

Recent widespread adoption of cerebral organoid protocols has led to many new studies assessing the human-specific features of neural diseases. However, not all organoid studies employ proper quality control, which limits the physiological relevance of their findings. Here, we discuss the stages of in vivo neocortex formation and how those stages are recapitulated in organoid protocols. We then present the first guide for real-time operator removal of maldeveloped organoids in shaking culture. Finally, we show preliminary work on an organoid imaging and mesofluidic control platform for automated quality control of organoid development. Taken together, this approach for assessing the morphological features of organoids will improve the rigor and reproducibility of organoid studies, increase effect sizes of physiologically relevant disease etiology, and pave the way for cortical organoid GMP in high-throughput. Clinical RelevanceThis establishes high-throughput, visual brain organoid quality control for disease studies and preclinical testing.

neuroscience↗

Reliability of high-quantity human brain organoids for modeling microcephaly, glioma invasion, and drug screening

Brain organoids offer unprecedented insights into brain development and disease modeling and hold promise for drug screening. Significant hindrances, however, are morphological and cellular heterogeneity, inter-organoid size differences, cellular stress, and poor reproducibility. Here, we describe a method that reproducibly generates thousands of organoids across multiple iPSC lines. These High Quantity brain organoids (Hi-Q brain organoids) exhibit reproducible cytoarchitecture, cell diversity, and functionality, are free from ectopically active cellular stress pathways, and allow cryopreservation and re-culturing. Using patient-derived Hi-Q brain organoids, we recapitulated distinct forms of microcephaly pathogenesis: primary microcephaly due to a mutation in centrosomal CDK5RAP2 and progeria-associated microcephaly in Cockayne syndrome. When modeling glioma invasion, hi-Q brain organoids displayed a similar invasion pattern for a given patient-derived glioma cell line. This enabled a medium-throughput screen to identify Selumetinib and Fulvestrant, which also perturbed glioma invasion in vivo. Thus, the Hi-Q approach can easily be adapted to reliably harness brain organoids utility for personalized disease modeling and drug discovery.

cell biology↗

Sofosbuvir protects human brain organoids against SARS-CoV-2

COVID-19 was rapidly declared a pandemic by the World Health Organization, only three months after the initial outbreak in Wuhan, China. Early clinical care mainly focused on respiratory illnesses. However, a variety of neurological manifestations in both adults and newborns are also emerging. To determine whether SARS-CoV-2 could target the human brain, we infected iPSC-derived human brain organoids. Our findings show that SARS-CoV-2 was able to infect and kill neural cells, including cortical neurons. This phenotype was accompanied by impaired synaptogenesis. Finally, Sofosbuvir, an FDA-approved antiviral drug, was able to rescue these alterations. Given that there are currently no vaccine or antiviral treatments available, urgent therapies are needed. Our findings put Sofosbuvir forward as a potential treatment to alleviate COVID-19-related neurological symptoms. One Sentence SummarySARS-CoV-2 infection causes neuronal death and impaired synaptogenesis, both rescued by Sofosbuvir treatment.

neuroscience↗

Molecular neuroanatomy of anorexia nervosa

Anorexia nervosa is a complex eating disorder with genetic, metabolic, and psychosocial underpinnings. Using unbiased genome-wide methods, recent studies have associated a variety of genes with the disorder. We characterized these genes by projecting them into aggregated gene expression data from reference transcriptomic atlases of the prenatal and adult human brain. We found that genes from an induced stem cell study of anorexia nervosa are expressed at higher levels in the lateral parabrachial and the ventral tegmental areas. The adult expression enrichment of the lateral parabrachial is confirmed with genes from two independent genetic studies. In the fetal brain, enrichment of the ventral tegmental area is also observed for the six genes near the only common variant associated with the disorder (rs4622308). We also observed signals in the adult and fetal pontine raphe, but they were not observed when using the genes from the genetic studies. In addition to signals related to calcitonin gene-related peptide neurons and the tachykinin, we found more than the expected number of microglia marker genes within the gene sets. Using mouse transcriptomic data, we identified several anorexia nervosa associated genes that are differentially expressed during food deprivation. While these genes that respond to fasting are not enriched in the gene sets, we highlight RPS26 which is proximal to rs4622308. We did not observe expression enrichment in the cingulate cortex or hypothalamus suggesting other targets for deep brain stimulation should be considered for severe cases. This work improves our understanding of the neurobiological causes of anorexia nervosa by suggesting disturbances in subcortical appetitive circuits.

neuroscience↗

Exosomes regulate Neurogenesis and Circuit Assembly in a Model of Rett Syndrome

Exosomes are thought to be secreted by all cells in the body and to be involved in intercellular communication. Here, we tested whether neural exosomes regulate the development of neural circuits and whether exosome-mediated signaling may be aberrant in the neurodevelopmental disorder Rett Syndrome (RTT). Quantitative proteomic analysis comparing exosomes from human induced pluripotent stem cells (hiPSC) - derived RTT patient or control neural cultures indicates that control exosomes contain signaling components capable of influencing neuronal development and function, which are lacking in RTT exosomes. Moreover, treatment with control exosomes rescues neuron number, apoptosis, synaptic puncta and synchronized firing phenotypes of MeCP2 knockdown in human primary neurons, indicating that exosomes have the capacity to influence neural development and may be a promising avenue to treat neurodevelopmental disorders like Rett Syndrome.

neuroscience↗