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The transmission of chronic wasting disease (CWD) has largely been attributed to contact with infectious prions shed in excretions (saliva, urine, feces, blood) by direct animal-to-animal exposure or indirect contact with the environment. Less-well studied has been the role that mother-to-offspring transmission may play in the facile transmission of CWD, and whether mother-to-offspring transmission before birth may contribute to the extensive spread of CWD. We thereby focused on a population of free-ranging white-tailed deer from West Virginia, USA, in which CWD has been detected. Fetal tissues, ranging from 113 to 158 days of gestation, were harvested from the uteri of CWD+ dams in the asymptomatic phase of infection. Using serial protein misfolding amplification (sPMCA), we detected evidence of prion seeds in 7 of 14 fetuses (50%) from 7 of 9 pregnancies (78%), with the earliest detection at 113 gestational days. This is the first report of CWD detection in free ranging white-tailed deer fetal tissues. Further investigation within cervid populations across North America will help define the role and impact of mother-to-offspring vertical transmission of CWD.

Somatic cell nuclear transfer (SCNT) is a key technology with broad applications that range from production of cloned farm animals to derivation of patient-matched stem cells or production of humanized animal organs for xenotransplantation. However, effects of aberrant epigenetic reprogramming on gene expression compromise cell and organ phenotype, resulting in low success rate of SCNT. Standard SCNT procedures include enucleation of recipient oocytes before the nuclear donor cell is introduced. Enucleation removes not only the spindle apparatus and chromosomes of the oocyte but also the perinuclear, mitochondria rich, ooplasm. Here, we use a Bos taurus SCNT model with in vitro fertilized (IVF) and in vivo conceived controls to demonstrate a ∼50% reduction in mitochondrial DNA (mtDNA) in the liver and skeletal muscle, but not the brain, of SCNT fetuses at day 80 of gestation. In the muscle, we also observed significantly reduced transcript abundances of mtDNA-encoded subunits of the respiratory chain. Importantly, mtDNA content and mtDNA transcript abundances correlate with hepatomegaly and muscle hypertrophy of SCNT fetuses. Expression of selected nuclear-encoded genes pivotal for mtDNA replication was similar to controls, arguing against an indirect epigenetic nuclear reprogramming effect on mtDNA amount. We conclude that mtDNA depletion is a major signature of perturbations after SCNT. We further propose that mitochondrial perturbation in interaction with incomplete nuclear reprogramming drives abnormal epigenetic features and correlated phenotypes, a concept supported by previously reported effects of mtDNA depletion on the epigenome and the pleiotropic phenotypic effects of mtDNA depletion in humans. This provides a novel perspective on the reprogramming process and opens new avenues to improve SCNT protocols for healthy embryo and tissue development., Competing Interests: MR is employed by the company Bayern-Genetik GmbH, Grub, Germany. The remaining authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2021 Bebbere, Ulbrich, Giller, Zakhartchenko, Reichenbach, Reichenbach, Verma, Wolf, Ledda and Hiendleder.)

Benefits from the use of cadavers in anatomical education are well described. Historically, human embryos and fetal cadavers were used in anatomy education to understand development and congenital malformations. Recently, three-dimensional printed models produced from archival fetal specimens, and online repositories of images from archival collections of embryos and fetuses, have been used as an educational tool in human development courses. Given that the archival specimens were likely obtained prior to the era of informed consent, this raises questions about their appropriate and ethical use. Because some institutions in the United States retain archival collections of embryonic and fetal specimens that were once used as educational tools, their existence and utility require frequent reexamination against contemporary ethical frameworks to guide appropriate use or utilization. Four ethical rationales for uses of these collections are examined, including destruction, indefinite storage, use in research, and use in health professions education. Guidelines for the use of archival collections of human embryos and fetuses are presented. Indefinite storage and use in health professions education are supported, while use in research is also permitted, however, such use is limited and dependent on circumstance and purpose. The development of current digital repositories and three-dimensionally printed models based on archival collections that were collected without informed consent, or those promoting commercial opportunity, are not supported. New embryonic and fetal donations obtained with informed consent should include reference to potential uses with new technology and virtual, genetic, or imaging applications., (© 2019 American Association of Anatomists.)

The infants of mothers with gestational diabetes mellitus (GDM) have an increased risk of metabolic and cardiovascular disease. It has been difficult to study the direct effects of maternal hyperglycemia on the fetus because of inaccessibility of fetal tissues. The development of tissues that simulate the function of fetal organs using stem cell technology provides an unprecedented opportunity to study this disorder. Stem cells in the Wharton's jelly of the umbilical cord (hWJSCs), possess unique properties that are different from other stem cells. They are primitive, present in large numbers, non-tumorigenic, hypoimmunogenic, tumoricidal, and carry a genetic signature that represents the fetus. They are multipotent but their differentiation into functional pancreatic and cardiovascular tissues has been challenging. We have been able to reprogram hWJSCs from normal and GDM cords into induced pluripotent stem cells (iPSCs) from which a variety of functional fetal tissues including insulin-producing and cardiovascular tissues could be derived. Such tissues from reprogrammed hWJSCs of normal and GDM cords that physiologically and genetically mimic the fetus of the diabetic or non-diabetic mother are an ideal platform to study the effects of glucose, the Zika virus, and other harmful agents on the fetus. The immature stemness phenotype of hWJSCs, easy accessibility, availability in large numbers without the need for propagation, and lower risk of accumulation of epigenetic mutations make them the most attractive candidate over other umbilical cord cell types for reprogramming. Additionally, some of their beneficial genes may be retained in memory in the iPSCs derived from them. J. Cell. Biochem. 118: 437-441, 2017. © 2016 Wiley Periodicals, Inc., (© 2016 Wiley Periodicals, Inc.)

Cornelia de Lange syndrome (CdLS) is a congenital developmental disorder characterized by craniofacial dysmorphia, growth retardation, limb malformations, and intellectual disability. Approximately 60% of patients with CdLS carry a recognizable pathological variant in the NIPBL gene, of which two isoforms, A and B, have been identified, and which only differ in the C-terminal segment. In this work, we describe the distribution pattern of the isoforms A and B mRNAs in tissues of adult and fetal origin, by qPCR (quantitative polymerase chain reaction). Our results show a higher gene expression of the isoform A, even though both seem to have the same tissue distribution. Interestingly, the expression in fetal tissues is higher than that of adults, especially in brain and skeletal muscle. Curiously, the study of fibroblasts of two siblings with a mild CdLS phenotype and a pathological variant specific of the isoform A of NIPBL (c.8387A > G; P.Tyr2796Cys), showed a similar reduction in both isoforms, and a normal sensitivity to DNA damage. Overall, these results suggest that the position of the pathological variant at the 3´ end of the NIPBL gene affecting only isoform A, is likely to be the cause of the atypical mild phenotype of the two brothers.

Objective: The discovery of free fetal DNA in plasma of pregnant women has opened a new avenue for non-invasive prenatal diagnosis. We hypothesized that epsilon (ɛ)-globin gene expression could serve as a positive control for the presence of fetal nucleic acid., Study Design: We measured ɛ-globin mRNA in human fetal tissues and compared concentrations with that measured in adult non-pregnant and pregnant samples. Total RNA was isolated from fetal marrow, liver, blood, and placenta (10-24 weeks gestation), from adult peripheral blood mononuclear cells, and from maternal plasma. RNA was reverse transcribed and quantitative polymerase chain reaction performed for ɛ-globin expression., Results: ɛ-globin gene expression was detected in all fetal samples, was detected in plasma of pregnant women, but was negligible in non-pregnant samples. Relative ɛ-globin gene expression was significantly greater in fetal blood compared to fetal liver, and was minimally expressed in placenta. ɛ-globin gene expression decreased at the highest gestational ages in fetal blood, while expression was greatest at 15-19 weeks in fetal marrow., Conclusion: Fetal ɛ-globin gene expression is significantly greater than adult expression and is increased in maternal plasma compared to non-pregnant samples. ɛ-globin gene expression might serve as a positive control when determining the presence of fetal nucleic acid in total nucleic acid isolated from maternal plasma.

The genetic mechanisms that regulate CFTR, the gene responsible for cystic fibrosis, have been widely investigated in cultured cells. However, mechanisms responsible for tissue-specific and time-specific expression are not completely elucidated in vivo. Through the survey of public databases, we found that the promoter of CFTR was associated with bivalent chromatin in human embryonic stem (ES) cells. In this work, we analyzed fetal (at different stages of pregnancy) and adult tissues and showed that, in digestive and lung tissues, which expressed CFTR, H3K4me3 was maintained in the promoter. Histone acetylation was high in the promoter and in two intronic enhancers, especially in fetal tissues. In contrast, in blood cells, which did not express CFTR, the bivalent chromatin was resolved (the promoter was labeled by the silencing mark H3K27me3). Cis-regulatory sequences were associated with lowly acetylated histones. We also provide evidence that the tissue-specific expression of CFTR is not regulated by dynamic changes of DNA methylation in the promoter. Overall, this work shows that a balance between activating and repressive histone modifications in the promoter and intronic enhancers results in the fine regulation of CFTR expression during development, thereby ensuring tissue specificity.

We review the first generations of clinical trials of novel cell therapies applied to a range of neurodegenerative diseases in the context of mechanisms of functional efficacy. This in turn helps to determine the best strategies to be adopted and the potential chances for success in developing new cell therapies to clinical application in different conditions. We then consider the scientific, technical, ethical, regulatory and logistic issues to be resolved in translating effective laboratory cell-based protocols to patients in clinical trials. We draw optimistic conclusions about the likelihood of success in developing radical new approaches to a range of devastating, and currently untreatable, neurodegenerative conditions, but caution that the problems are complex and the solutions are likely to be slow and costly to achieve in order to overcome significant ethical and regulatory as well as scientific challenges., (Copyright © 2013 Elsevier Inc. All rights reserved.)

Busulfan, an antineoplastic bifunctional-alkylating agent, is known to induce developmental anomalies. In the present study, we examined the distribution and sequence of pyknotic cells in rat fetal tissues exposed to busulfan. Pregnant rats on gestation day 13 were administered intraperitoneally 30 mg/kg of busulfan, and fetal tissues were examined at 6, 12, 24, 36, 48, 72 and 96 hours after treatment (HAT). Pyknosis of component cells was observed markedly in the brain, moderately in the eyes and spinal cord and mildly in the craniofacial tissue, mandible, limb buds, tail bud, ganglions, alimentary tract, lungs, kidneys, pancreas and liver. In the brain, mitotic inhibition was also detected. Most of the pyknotic cells were considered to be apoptotic cells judging from the results of TUNEL staining and electron microscopic examination. Commonly in the above-mentioned tissues, pyknotic cells began to increase at 24 HAT, peaked at 36 or 48 HAT and disappeared at 96 HAT, which is when the histological picture returned to normal in most tissues except for the brain, spinal cord and eyes. The present study clarified the outline of busulfan-induced apoptosis in rat fetuses.