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Golos, T. G.

Publications and source records attributed to Golos, T. G..

3 recordsLinked to original sources

Haplotype-phased Callithrix jacchus embryonic stem cell line for genome editing using CRISPR/Cas9

Due to anatomical and physiological similarities to humans, the common marmoset (Callithrix jacchus) is an ideal organism for the study human diseases. Researchers are currently leveraging genome-editing technologies such as CRISPR/Cas9 to genetically engineer marmosets for the in vivo biomedical modeling of human neuropsychiatric and neurodegenerative diseases. The genome characterization of these cell lines greatly reinforces these transgenic efforts. It also provides the genomic contexts required for the accurate interpretation of functional genomics data. We performed haplotype-resolved whole-genome characterization for marmoset ESC line cj367 from the Wisconsin National Primate Research Center. This is the first haplotype-resolved analysis of a marmoset genome and the first whole-genome characterization of any marmoset ESC line. We identified and phased single-nucleotide variants (SNVs) and Indels across the genome. By leveraging this haplotype information, we then compiled a list of cj367 ESC allele-specific CRISPR targeting sites. Furthermore, we demonstrated successful Cas9 Endonuclease Dead (dCas9) expression and targeted localization in cj367 as well as sustained pluripotency after dCas9 transfection by teratoma assay. Lastly, we show that these ESCs can be directly induced into functional neurons in a rapid, single-step process. Our study provides a valuable set of genomic resources for primate transgenics in this post-genome era.

genetics

Ocular and uteroplacental pathology in macaque congenital Zika virus infection

Congenital Zika virus (ZIKV) infection impacts fetal development and pregnancy outcomes. We infected a pregnant rhesus macaque with a Puerto Rican ZIKV isolate in the first trimester. The pregnancy was complicated by preterm premature rupture of membranes (PPROM) and fetal demise 49 days post infection (gestational day 95). Significant pathology at the maternal-fetal interface included acute chorioamnionitis, placental infarcts, and leukocytoclastic vasculitis of the myometrial radial arteries. ZIKV RNA was disseminated throughout the fetus tissues and maternal immune system at necropsy, as assessed by quantitative RT-PCR for viral RNA. Replicating ZIKV was identified in fetal tissues, maternal lymph node, and maternal spleen by fluorescent in situ hybridization for viral replication intermediates. Fetal ocular pathology included a choroidal coloboma, suspected anterior segment dysgenesis, and a dysplastic retina. This is the first report of ocular pathology and prolonged viral replication in both maternal and fetal tissues following congenital ZIKV infection in rhesus macaques. PPROM followed by fetal demise and severe pathology of the visual system have not been described in macaque congenital infection previously; further nonhuman primate studies are needed to determine if an increased risk for PPROM is associated with congenital Zika virus infection.\n\nAuthor summaryA ZIKV infection during pregnancy is associated with malformations in fetal development including, but not limited to, ocular and brain anomalies, such as microcephaly, and stillbirth. The development of an accurate pregnancy model to study the effects of ZIKV will provide insight into vertical transmission, ZIKV tissue distribution, and fetal injury and malformations. Non-human primates closely resemble human in terms of the reproductive system, immunity, placentation and pregnancy. Our study demonstrates that the rhesus macaque is a compelling model in which to study ZIKV during pregnancy due to similar outcomes between the human and rhesus macaque. These similarities include prolonged viremia, vertical transmission, adverse pregnancy outcomes and fetal pathology, including defects in the visual system.

pathology

Highly efficient maternal-fetal Zika virus transmission in pregnant rhesus macaques

Infection with Zika virus (ZIKV) is associated with human congenital fetal anomalies. To model fetal outcomes in nonhuman primates, we administered Asian-lineage ZIKV subcutaneously to four pregnant rhesus macaques. While non-pregnant animals clear viremia within 10-12 days, maternal viremia was prolonged in 3 of 4 pregnancies. Fetal head growth velocity in the last month of gestation determined by ultrasound assessment of head circumference was decreased in comparison with biparietal diameter and femur length within each fetus, both within normal range. ZIKV RNA was detected in tissues from all four fetuses at term cesarean section. In all pregnancies, neutrophilic infiltration was present at the maternal-fetal interface (decidua, placenta, fetal membranes), in various fetal tissues, and in fetal retina, choroid, and optic nerve (first trimester infection only). Consistent vertical transmission in this primate model may provide a platform to assess risk factors and test therapeutic interventions for interruption of fetal infection.

pathology