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Objective: We explored the potential of genome‐wide epigenomic liquid biopsy for the comprehensive analysis of cell‐free DNA (cfDNA) methylation signatures in maternal plasma in early gestation. Method: We used solution phase hybridization for targeted region capture of bisulfite‐converted DNA obtained from plasma of pregnant women in early gestation and nonpregnant female controls. Results: Targeted sequencing of ~80.5 Mb of the plasma methylome generated an average read depth across all 17 plasma samples of ~42x. We used these data to explore the pregnancy‐specific characteristics of cfDNA methylation in plasma and found that pregnancy resulted in clearly detectable global alterations in DNA methylation patterns that were influenced by genomic location. We analyzed similar, previously published, data from first‐trimester maternal leukocyte populations and gestational age–matched chorionic villus (CV) and confirmed that tissue‐specific DNA methylation signatures in these samples had a significant influence on global and gene‐specific methylation in the plasma of pregnant women. Conclusion: We describe an approach for targeted epigenomic liquid biopsy in pregnancy and discuss our findings in the context of noninvasive prenatal testing with respect to phenotypic pregnancy monitoring and the early detection of complex gestational phenotypes such as preeclampsia and preterm birth. [ABSTRACT FROM AUTHOR]

Major depressive disorder (MDD) affects approximately 15 million Americans. Approximately 2 million of these are classified as being refractory to treatment (TR‐MDD). Because of the lack of available therapies for TR‐MDD, and the high risk of suicide, there is interest in identifying new treatment modalities and diagnostic methods. Understanding of the impact of genomic copy number variation in the etiology of a variety of neuropsychiatric phenotypes is increasing. Low copy repeat elements at 15q13.3 facilitate non‐allelic homologous recombination, resulting in recurrent copy number variants (CNVs). Numerous reports have described association between microdeletions in this region and a variety of neuropsychiatric phenotypes, with CHRNA7 implicated as a candidate gene. However, the pathogenicity of 15q13.3 duplications is less clear. As part of an ongoing study, in which we have identified a number of metabolomic anomalies in spinal fluid from TR‐MDD patients, we also evaluated genomic copy number variation in patients (n = 125) and controls (n = 26) via array‐based copy number genomic hybridization (CGH); the case frequency was compared with frequencies reported in a prior study as well as a larger population‐sized cohort. We identified five TR‐MDD patients with microduplications involving CHRNA7. CHRNA7 duplications are the most common CNVs identified by clinical CGH in this cohort. Therefore, this study provides insight into the potential involvement of CHRNA7 duplications in the etiology of TR‐MDD and informs those involved with care of affected individuals. [ABSTRACT FROM AUTHOR]

Background: A variety of neurological disorders including neurodegenerative diseases and infection by neurotropic viruses can cause structural and functional changes in the central nervous system (CNS), resulting in long-term neurological sequelae. An improved understanding of the pathogenesis of these disorders is important for developing efficacious interventions. Human induced pluripotent stem cells (hiPSCs) offer an extraordinary window for modeling pathogen-CNS interactions, and other cellular interactions, in three-dimensional (3D) neuronal cultures that can recapitulate several aspects of in vivo brain tissue. Methods: Herein, we describe a prototype of scaffold-free hiPSC-based adherent 3D (A-3D) human neuronal cultures in 96-well plates. To test their suitability for drug screening, A-3D neuronal cultures were infected with herpes simplex virus type 1 (HSV-1) with or without acyclovir. Results: The half maximal inhibitory concentration (IC50) of acyclovir was 3.14 μM and 3.12 μM determined using flow cytometry and the CX7 High Content Screening platform, respectively. Conclusions: Our A-3D neuronal cultures provide an unprecedented opportunity for high-content drug screening programs to treat human CNS infections. [ABSTRACT FROM AUTHOR]

Herpes simplex virus 1 (HSV-1) establishes latency in both peripheral nerve ganglia and the central nervous system (CNS). The outcomes of acute and latent infections in these different anatomic sites appear to be distinct. It is becoming clear that many of the existing culture models using animal primary neurons to investigate HSV-1 infection of the CNS are limited and not ideal, and most do not recapitulate features of CNS neurons. Human induced pluripotent stem cells (hiPSCs) and neurons derived from them are documented as tools to study aspects of neuropathogenesis, but few have focused on modeling infections of the CNS. Here, we characterize functional twodimensional (2D) CNS-like neuron cultures and three-dimensional (3D) brain organoids made from hiPSCs to model HSV-1-human-CNS interactions. Our results show that (i) hiPSC-derived CNS neurons are permissive for HSV-1 infection; (ii) a quiescent state exhibiting key landmarks of HSV-1 latency described in animal models can be established in hiPSC-derived CNS neurons; (iii) the complex laminar structure of the organoids can be efficiently infected with HSV, with virus being transported from the periphery to the central layers of the organoid; and (iv) the organoids support reactivation of HSV-1, albeit less efficiently than 2D cultures. Collectively, our results indicate that hiPSC-derived neuronal platforms, especially 3D organoids, offer an extraordinary opportunity for modeling the interaction of HSV-1 with the complex cellular and architectural structure of the human CNS. [ABSTRACT FROM AUTHOR]

Acyclovir (ACV) is an effective antiviral agent for treating lytic Herpes Simplex virus, type 1 (HSV-1) infections, and it has dramatically reduced the mortality rate of herpes simplex encephalitis. However, HSV-1 resistance to ACV and its derivatives is being increasingly documented, particularly among immunocompromised individuals. The burgeoning drug resistance compels the search for a new generation of more efficacious anti-herpetic drugs. We have previously shown that trans-dihydrolycoricidine (R430), a lycorane-type alkaloid derivative, effectively inhibits HSV-1 infections in cultured cells. We now report that R430 also inhibits ACV-resistant HSV-1 strains, accompanied by global inhibition of viral gene transcription and enrichment of H3K27me3 methylation on viral gene promoters. Furthermore, we demonstrate that R430 prevents HSV-1 reactivation from latency in an ex vivo rodent model. Finally, among a panel of DNA viruses and RNA viruses, R430 inhibited Zika virus with high therapeutic index. Its therapeutic index is comparable to standard antiviral drugs, though it has greater toxicity in non-neuronal cells than in neuronal cells. Synthesis of additional derivatives could enable more efficacious antivirals and the identification of active pharmacophores.