Transcriptome analysis and functional characterization of cerebral organoids in bipolar disorder

Background Reprogramming human induced pluripotent stem cells (iPSCs) from somatic cells and generating three-dimensional brain organoids from these iPSCs provide access to live human neuronal tissue with disease-specific genetic backgrounds. Methods Cerebral organoids were generated from iPSCs of eight bipolar disorder (BPI) patients and eight healthy control individuals. RNA-seq experiments were undertaken using RNA isolated from the cerebral organoids. Functional activity in the cerebral organoids was studied using microelectrode arrays. Results RNA-seq data comparing gene expression profiles in the cerebral organoids showed downregulation of pathways involved in cell adhesion, neurodevelopment, and synaptic biology in bipolar disorder along with upregulation of genes involved in immune signaling. The central hub in the network analysis was neurocan (NCAN), which is located in a locus with evidence for genome-wide significant association in BPI. Gene ontology analyses suggested deficits related to endoplasmic reticulum biology in BPI, which was supported by cellular characterization of ER–mitochondria interactions. Functional studies with microelectrode arrays revealed specific deficits in response to stimulation and depolarization in BPI cerebral organoids. Conclusions Our studies in cerebral organoids from bipolar disorder showed dysregulation in genes involved in cell adhesion, immune signaling, and endoplasmic reticulum biology; implicated a central role for the GWAS hit NCAN in the biology of BPI; and showed evidence of deficits in neurotransmission.


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KaryoStat™ analysis of CUB12899-12 revealed the sample originated from a male individual 2.
No chromosomal aberrations were found when comparing against the reference dataset ( Figure 21) KaryoStat™ Results: CUB12899-12 Disclaimer: This assay was conducted solely for the listed investigator/institution. The results of this assay are for research use only. Figure 21: Whole genome view. The whole genome view displays all somatic and sex chromosomes in one frame with high level copy number. The smooth signal plot (right y-axis) is the smoothing of the log2 ratios which depict the signal intensities of probes on the microarray. A value of 2 represents a normal copy number state (CN = 2). A value of 3 represents chromosomal gain (CN = 3). A value of 1 represents a chromosomal loss (CN = 1). The pink, green and yellow colors indicate the raw signal for each individual chromosome probe, while the blue signal represents the normalized probe signal which is used to identify copy number and aberrations (if any).

Copy Number State
Figure 1: Whole genome view. The whole genome view displays all somatic and sex chromosomes in one frame with high level copy number. The smooth signal plot (right y-axis) is the smoothing of the log2 ratios which depict the signal intensities of probes on the microarray. A value of 2 represents a normal copy number state (CN = 2). A value of 3 represents chromosomal gain (CN = 3). A value of 1 represents a chromosomal loss (CN = 1). The pink, green and yellow colors indicate the raw signal for each individual chromosome probe, while the blue signal represents the normalized probe signal which is used to identify copy number and aberrations (if any). The whole genome view analysis revealed chromosomal aberrations indicated by the red arrow.  The whole genome view displays all somatic and sex chromosomes in one frame with high level copy number. The smooth signal plot (right y-axis) is the smoothing of the log2 ratios which depict the signal intensities of probes on the microarray. A value of 2 represents a normal copy number state (CN = 2). A value of 3 represents chromosomal gain (CN = 3). A value of 1 represents a chromosomal loss (CN = 1). The pink, green and yellow colors indicate the raw signal for each individual chromosome probe, while the blue signal represents the normalized probe signal which is used to identify copy number and aberrations (if any).     The whole genome view displays all somatic and sex chromosomes in one frame with high level copy number. The smooth signal plot (right y-axis) is the smoothing of the log2 ratios which depict the signal intensities of probes on the microarray. A value of 2 represents a normal copy number state (CN = 2). A value of 3 represents chromosomal gain (CN = 3). A value of 1 represents a chromosomal loss (CN = 1). The pink, green and yellow colors indicate the raw signal for each individual chromosome probe, while the blue signal represents the normalized probe signal which is used to identify copy number and aberrations (if any).

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KaryoStat™ analysis of CUB12899r-1 revealed the sample originated from a male individual 2. Chromosomal aberrations were observed when comparing to the reference set (Table 2, Figure 1)

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A supplemental document with detailed information on the aberration will be provided to the Client    Figure 3)

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A supplemental document with detailed information on the aberration will be provided to the Client  The whole genome view displays all somatic and sex chromosomes in one frame with high level copy number. The smooth signal plot (right y-axis) is the smoothing of the log2 ratios which depict the signal intensities of probes on the microarray. A value of 2 represents a normal copy number state (CN = 2). A value of 3 represents chromosomal gain (CN = 3). A value of 1 represents a chromosomal loss (CN = 1). The pink, green and yellow colors indicate the raw signal for each individual chromosome probe, while the blue signal represents the normalized probe signal which is used to identify copy number and aberrations (if any). The whole genome view analysis revealed chromosomal aberrations indicated by the red arrow.       Figure 3)

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A supplemental document with detailed information on the aberration will be provided to the Client  The whole genome view displays all somatic and sex chromosomes in one frame with high level copy number. The smooth signal plot (right y-axis) is the smoothing of the log2 ratios which depict the signal intensities of probes on the microarray. A value of 2 represents a normal copy number state (CN = 2). A value of 3 represents chromosomal gain (CN = 3). A value of 1 represents a chromosomal loss (CN = 1). The pink, green and yellow colors indicate the raw signal for each individual chromosome probe, while the blue signal represents the normalized probe signal which is used to identify copy number and aberrations (if any). The whole genome view analysis revealed chromosomal aberrations indicated by the red arrow.   The whole genome view displays all somatic and sex chromosomes in one frame with high level copy number. The smooth signal plot (right y-axis) is the smoothing of the log2 ratios which depict the signal intensities of probes on the microarray. A value of 2 represents a normal copy number state (CN = 2). A value of 3 represents chromosomal gain (CN = 3). A value of 1 represents a chromosomal loss (CN = 1). The pink, green and yellow colors indicate the raw signal for each individual chromosome probe, while the blue signal represents the normalized probe signal which is used to identify copy number and aberrations (if any).