Project description:Classic Human Astrovirus 4, 8, MLB-3 and likely new genotype 5 sub-lineage in stool samples of children with Acute Flaccid Paralysis (AFP) in Nigeria
Project description:Human astrovirus infection is known to disrupt intestinal barrier function by increasing barrier permeabilty. However, the exact cellular mechanism(s) involved is unknown. We used microarrays to detail the global gene expression changes occuring during astrovirus infection and identify necessary cellular pathways for astrovirus pathogenesis.
Project description:Transcriptome analysis of RNA extracted from human induced pluripotent stem cell (hipsc)-derived neurons exposed to botulinum neurotoxin type A1 (BoNT/A1) and an atoxic derivative, BoNT/A ad. Botulinum neurotoxin type A1 (BoNT/A1) is a potent protein toxin responsible for the potentially fatal human illness botulism. Despite this, the long-lasting flaccid muscle paralysis caused by BoNT/A has led to its rise as a powerful and versatile bio-pharmaceutical. The flaccid paralysis is due to specific cleavage of SNAREs by BoNTs inside neurons. However, potential effects of BoNTs on intoxicated neurons besides the cleavage of SNAREs have not been studied in detail. In this study we investigated by microarray analysis the effects of BoNT/A and a catalytically inactive derivative (BoNT/A ad) on the transcriptome of human induced pluripotent stem cell (hiPSC)-derived neurons at 2 days and 2 weeks after exposure. While there were only minor changes in expression levels at 2 days post exposure, at 2 weeks post exposure 492 genes were differentially expressed more than 2-fold in BoNT/A1-exposed cells when compared to non-exposed populations, and 682 genes were differentially expressed in BoNT/A ad-exposed cells. The vast majority of genes were similarly regulated in BoNT/A1 and BoNT/A ad-exposed neurons, and the few genes differentially regulated between BoNT/A1 and BoNT/A ad-exposed neurons were regulated less than 3.5 fold. These data indicate a similar response of neurons to BoNT/A1 and BoNT/A ad exposure. The most highly regulated genes in cells exposed to either BoNT/A1 or BoNT/A ad are involved in neurite outgrowth and calcium channel sensitization.
2014-09-15 | GSE58149 | GEO
Project description:Ten previously unassigned Human Cosavirus types detected in faeces of children with Non-polio Acute Flaccid Paralysis in Nigeria in 2020
Project description:The cellular response to astrovirus infection is not well defined. We used single cell RNA sequencing (scRNA-seq) to determine cellular response to astrovirus early or late in infection.
Project description:Transcriptome analysis of RNA extracted from human induced pluripotent stem cell (hipsc)-derived neurons exposed to botulinum neurotoxin type A1 (BoNT/A1) and an atoxic derivative, BoNT/A ad. Botulinum neurotoxin type A1 (BoNT/A1) is a potent protein toxin responsible for the potentially fatal human illness botulism. Despite this, the long-lasting flaccid muscle paralysis caused by BoNT/A has led to its rise as a powerful and versatile bio-pharmaceutical. The flaccid paralysis is due to specific cleavage of SNAREs by BoNTs inside neurons. However, potential effects of BoNTs on intoxicated neurons besides the cleavage of SNAREs have not been studied in detail. In this study we investigated by microarray analysis the effects of BoNT/A and a catalytically inactive derivative (BoNT/A ad) on the transcriptome of human induced pluripotent stem cell (hiPSC)-derived neurons at 2 days and 2 weeks after exposure. While there were only minor changes in expression levels at 2 days post exposure, at 2 weeks post exposure 492 genes were differentially expressed more than 2-fold in BoNT/A1-exposed cells when compared to non-exposed populations, and 682 genes were differentially expressed in BoNT/A ad-exposed cells. The vast majority of genes were similarly regulated in BoNT/A1 and BoNT/A ad-exposed neurons, and the few genes differentially regulated between BoNT/A1 and BoNT/A ad-exposed neurons were regulated less than 3.5 fold. These data indicate a similar response of neurons to BoNT/A1 and BoNT/A ad exposure. The most highly regulated genes in cells exposed to either BoNT/A1 or BoNT/A ad are involved in neurite outgrowth and calcium channel sensitization. 18 samples were used for this project: 6 populations were exposed to BoNT/A1, 6 to BoNT/A ad, and 6 were non-exposed. All exposures lasted for 48h, at which point 3 samples of each exposure group were harvested (2d condition), and the remaining 3 samples were grown for an additional 12d (2wk condition). Analysis was performed using the Affymetrix HG U133 Plus 2.0 array, and data was extracted using the Affymetrix Expression Console v 1.2.0.20 software
Project description:Zika virus (ZIKV) is an emerging, mosquito-borne pathogen associated with a widespread 2015–2016 epidemic in the Western Hemisphere and a proven cause of microcephaly and other fetal brain defects in infants born to infected mothers. ZIKV infections have been also linked to other neurological illnesses in infected adults and children, including Guillain-Barré syndrome (GBS), acute flaccid paralysis (AFP) and meningoencephalitis, but the viral pathophysiology behind those conditions remains poorly understood. Here we investigated ZIKV infectivity in neuroblastoma SH-SY5Y cells, both undifferentiated and following differentiation with retinoic acid. We perform RNA seq, and global trancriptome analysis to corroborate the effect of retinoic acid in SH-SY5Y cells. Then we analyze the virus infection in differentiated and undifferntiated cells. We found that multiple ZIKV strains, representing both the prototype African and contemporary Asian epidemic lineages, were able to replicate in SH-SY5Y cells. Differentiation with resultant expression of mature neuron markers increased infectivity in these cells, and the extent of infectivity correlated with degree of differentiation. Enhanced ZIKV infectivity in a neural cell line following differentiation may contribute to viral neuropathogenesis in the developing or mature central nervous system.
Project description:With the near eradication of poliovirus due to global vaccination campaigns, attention has shifted to other enteroviruses that can cause polio-like paralysis syndrome (now termed acute flaccid myelitis (AFM)). In particular, enterovirus D68 (EV-D68) is believed to be the main driver of epidemic outbreaks of AFM in recent years, yet not much is known about EV-D68 host interactions. EV-D68 is a respiratory virus but, in rare cases, can spread to the central nervous system to cause severe neuropathogenesis. We use genome-scale CRISPR screens to identify genes important for EV-D68 infection. A549 and U87-MG cells were stably transduced with lentiCas9-Blast (Addgene, #52962) and subsequently selected using Blasticidin. Then, 300 million cells that constitutively express Cas9 were transduced with lentiGuide-Puro from the Brunello library (MOI 0.3). Cells were then selected with puromycin, expanded to 3 billion cells, and then pooled together and cryofrozen in aliquots. One hundred million cells were thawed constituting over 1000× genome coverage worth of mutagenized library,expanded, and seeded for the screens. Each screen had over 500x genome coverage. The cells were infected with EV-D68 IL (BEI USA/2014/18952) (MOI 0.1). Virus-resistant colonies were harvested. The uninfected reference used was the unselected starting population. The unselected and selected cells were both processed with QIAamp DNA columns to purify the gDNA. A first round of PCR was used to amplify the guide RNA sequences encoded in the gDNA, followed by a second round of PCR to add the barcodes/adapters for amplicon sequencing. 2% agarose gels and a QIAquick gel extraction kit were used to purify the amplicons. The amplicons were then subjected to next-generation sequencing on a HiSeq instrument lane (Illumina) via Novogene.
Project description:Infections of the central nervous system (CNS) in humans are on the rise due to changing environmental conditions and increase in vulnerable populations comprised of immunocompromised subjects with primary (genetic) or secondary (acquired) immunodeficiency. Many viruses take the opportunity to invade the CNS by capitalizing on impaired immunity of the host. Here we investigate neuropathogenesis of a rare CNS infection in immunocompromised patients caused by the astrovirus and show that it shares many features with another opportunistic infection of the CNS associated with human immunodeficiency virus. We show that astrovirus infects CNS neurons with a major impact on the brainstem. This leads to disrupted synaptic integrity loss of afferent innervation related to infected neurons and global impairment of both excitatory and inhibitory neurotransmission. In the settings of impaired peripheral adaptive immunity host responses to astrovirus infection are dominated by the microglia-macrophage-phagocytosis axis which may be a common compensatory defense mechanism employed by the CNS against opportunistic infections.