scholarly journals Altered Cogs of the Clock: Insights into the Embryonic Etiology of Spondylocostal Dysostosis

2021 ◽  
Vol 9 (1) ◽  
pp. 5
Author(s):  
Ana Nóbrega ◽  
Ana C. Maia-Fernandes ◽  
Raquel P. Andrade
Keyword(s):  
Molecular Mechanisms ◽  
Axial Skeleton ◽  
In Vitro Models ◽  
Great Promise ◽  
Cellular Events ◽  
Spondylocostal Dysostosis ◽  
Congenital Condition ◽  
Body Segmentation ◽  
Severity Of The Disease

Spondylocostal dysostosis (SCDO) is a rare heritable congenital condition, characterized by multiple severe malformations of the vertebrae and ribs. Great advances were made in the last decades at the clinical level, by identifying the genetic mutations underlying the different forms of the disease. These were matched by extraordinary findings in the Developmental Biology field, which elucidated the cellular and molecular mechanisms involved in embryo body segmentation into the precursors of the axial skeleton. Of particular relevance was the discovery of the somitogenesis molecular clock that controls the progression of somite boundary formation over time. An overview of these concepts is presented, including the evidence obtained from animal models on the embryonic origins of the mutant-dependent disease. Evidence of an environmental contribution to the severity of the disease is discussed. Finally, a brief reference is made to emerging in vitro models of human somitogenesis which are being employed to model the molecular and cellular events occurring in SCDO. These represent great promise for understanding this and other human diseases and for the development of more efficient therapeutic approaches.

scholarly journals Molecular Aspects of Varicella-Zoster Virus Latency

2018 ◽  
Author(s):  
Daniel P. Depledge ◽  
Tomohiko Sadaoka ◽  
Werner J. D. Ouwendijk
Keyword(s):  
Varicella Zoster Virus ◽  
Molecular Mechanisms ◽  
Neurological Complications ◽  
In Vitro Models ◽  
New Era ◽  
Varicella Zoster ◽  
Virus Latency ◽  
Technological Advances ◽  
Molecular Aspects

Primary varicella-zoster virus (VZV) infection causes varicella (chickenpox) and the establishment of a lifelong latent infection in ganglionic neurons. VZV reactivates in about one-third of infected individuals to cause herpes zoster, often accompanied by neurological complications. The restricted host range of VZV and, until recently, the lack of suitable in vitro models to study VZV latency have seriously hampered molecular studies of viral latency. Nevertheless, recent technological advances facilitated a series of exciting studies that resulted in the discovery of a VZV latency-associated transcript (VLT) and have redefined our understanding of VZV latency and factors that initiate reactivation. Together, these findings pave the way for a new era of research that may finally unravel the precise molecular mechanisms that govern latency. In this review, we will summarize the implications of recent discoveries in the VZV latency field from both a virus and host perspective and provide a roadmap for future studies.

Computational profiling of hiPSC-derived heart organoids reveals chamber defects associated with Ebstein’s anomaly

2020 ◽  
Author(s):  
Wei Feng ◽  
Hannah Schriever ◽  
Shan Jiang ◽  
Abha Bais ◽  
Dennis Kostka ◽  
...  
Keyword(s):  
Heart Development ◽  
Cell Types ◽  
In Vitro Models ◽  
Ebstein’S Anomaly ◽  
Great Promise ◽  
Heart Cells ◽  
Ebstein's Anomaly ◽  
Disease States ◽  
Human Fetal Heart

AbstractHeart organoids have the potential to generate primary heart-like anatomical structures and hold great promise as in vitro models for cardiac disease. However, their properties have not yet been carefully studied, which hinders a wider spread application. Here we report the development of differentiation systems for ventricular and atrial heart organoids, enabling the study of heart disease with chamber defects. We show that our systems generate organoids comprising of major cardiac cell types, and we used single cell RNA sequencing together with sample multiplexing to characterize the cells we generate. To that end, we also developed a machine learning label transfer approach lever-aging cell type, chamber, and laterality annotations available for primary human fetal heart cells. We then used this model to analyze organoid cells from an isogeneic line carrying an Ebstein’s anomaly associated genetic variant, and we successfully recapitulated the disease’s atrialized ventricular defects. In summary, we have established a workflow integrating heart organoids and computational analysis to model heart development in normal and disease states.

scholarly journals Direct SARS-CoV-2 infection of the human inner ear may underlie COVID-19-associated audiovestibular dysfunction

2021 ◽  
Vol 1 (1) ◽  
Author(s):  
Minjin Jeong ◽  
Karen E. Ocwieja ◽  
Dongjun Han ◽  
P. Ashley Wackym ◽  
Yichen Zhang ◽  
...  
Keyword(s):  
Inner Ear ◽  
Hair Cells ◽  
Molecular Mechanisms ◽  
Three Dimensional ◽  
Induced Pluripotent Stem Cell ◽  
In Vitro Models ◽  
Cellular Models ◽  
Induced Pluripotent ◽  
Human Inner Ear

Abstract Background COVID-19 is a pandemic respiratory and vascular disease caused by SARS-CoV-2 virus. There is a growing number of sensory deficits associated with COVID-19 and molecular mechanisms underlying these deficits are incompletely understood. Methods We report a series of ten COVID-19 patients with audiovestibular symptoms such as hearing loss, vestibular dysfunction and tinnitus. To investigate the causal relationship between SARS-CoV-2 and audiovestibular dysfunction, we examine human inner ear tissue, human inner ear in vitro cellular models, and mouse inner ear tissue. Results We demonstrate that adult human inner ear tissue co-expresses the angiotensin-converting enzyme 2 (ACE2) receptor for SARS-CoV-2 virus, and the transmembrane protease serine 2 (TMPRSS2) and FURIN cofactors required for virus entry. Furthermore, hair cells and Schwann cells in explanted human vestibular tissue can be infected by SARS-CoV-2, as demonstrated by confocal microscopy. We establish three human induced pluripotent stem cell (hiPSC)-derived in vitro models of the inner ear for infection: two-dimensional otic prosensory cells (OPCs) and Schwann cell precursors (SCPs), and three-dimensional inner ear organoids. Both OPCs and SCPs express ACE2, TMPRSS2, and FURIN, with lower ACE2 and FURIN expression in SCPs. OPCs are permissive to SARS-CoV-2 infection; lower infection rates exist in isogenic SCPs. The inner ear organoids show that hair cells express ACE2 and are targets for SARS-CoV-2. Conclusions Our results provide mechanistic explanations of audiovestibular dysfunction in COVID-19 patients and introduce hiPSC-derived systems for studying infectious human otologic disease.

scholarly journals Cortical Spheroid Model for Studying the Effects of Ischemic Brain Injury

2021 ◽  
Author(s):  
Rachel M McLaughlin ◽  
Amanda Laguna ◽  
Ilayda Top ◽  
Christien Hernadez ◽  
Liane L Livi ◽  
...  
Keyword(s):  
Molecular Mechanisms ◽  
Three Dimensional ◽  
Cost Effective ◽  
Glucose Deprivation ◽  
In Vitro Models ◽  
3D Architecture ◽  
A Cell ◽  
Antioxidant Agent

Stroke is a devastating neurological disorder and a leading cause of death and long-term disability. Despite many decades of research, there are still very few therapeutic options for patients suffering from stroke or its consequences. This is partially due to the limitations of current research models, including traditional in vitro models which lack the three-dimensional (3D) architecture and cellular make-up of the in vivo brain. 3D spheroids derived from primary postnatal rat cortex provide an in vivo-relevant model containing a similar cellular composition to the native cortex and a cell-synthesized extracellular matrix. These spheroids are cost-effective, highly reproducible, and can be produced in a high-throughput manner, making this model an ideal candidate for screening potential therapeutics. To study the cellular and molecular mechanisms of stroke in this model, spheroids were deprived of glucose, oxygen, or both oxygen and glucose for 24 hours. Both oxygen and oxygen-glucose deprived spheroids demonstrated many of the hallmarks of stroke, including a decrease in metabolism, an increase in neural dysfunction, and an increase in reactive astrocytes. Pretreatment of spheroids with the antioxidant agent N-acetylcysteine (NAC) mitigated the decrease in ATP seen after 24 hours of oxygen-glucose deprivation. Together, these results show the utility of our 3D cortical spheroid model for studying ischemic injury and its potential for screening stroke therapeutics.

scholarly journals Establishment of novel in vitro mouse chief cell and SPEM cultures identifies MAL2 as a marker of metaplasia in the stomach

2014 ◽  
Vol 307 (8) ◽  
pp. G777-G792 ◽  
Author(s):  
Victoria G. Weis ◽  
Christine P. Petersen ◽  
Jason C. Mills ◽  
Pamela L. Tuma ◽  
Robert H. Whitehead ◽  
...  
Keyword(s):  
Molecular Mechanisms ◽  
Expression Profiles ◽  
In Vitro Models ◽  
Chief Cell ◽  
Nonpermissive Temperature ◽  
Transcriptional Expression ◽  
Chief Cells ◽  
Pepsinogen C

Oxyntic atrophy in the stomach leads to chief cell transdifferentiation into spasmolytic polypeptide expressing metaplasia (SPEM). Investigations of preneoplastic metaplasias in the stomach are limited by the sole reliance on in vivo mouse models, owing to the lack of in vitro models for distinct normal mucosal lineages and metaplasias. Utilizing the Immortomouse, in vitro cell models of chief cells and SPEM were developed to study the characteristics of normal chief cells and metaplasia. Chief cells and SPEM cells isolated from Immortomice were cultured and characterized at both the permissive (33°C) and the nonpermissive temperature (39°C). Clones were selected on the basis of their transcriptional expression of specific stomach lineage markers (named ImChief and ImSPEM) and protein expression and growth were analyzed. The transcriptional expression profiles of ImChief and ImSPEM cells were compared further by using gene microarrays. ImChief cells transcriptionally express most chief cell markers and contain pepsinogen C and RAB3D-immunostaining vesicles. ImSPEM cells express the SPEM markers TFF2 and HE4 and constitutively secrete HE4. Whereas ImChief cells cease proliferation at the nonpermissive temperature, ImSPEM cells continue to proliferate at 39°C. Gene expression profiling of ImChief and ImSPEM revealed myelin and lymphocyte protein 2 (MAL2) as a novel marker of SPEM lineages. Our results indicate that the expression and proliferation profiles of the novel ImChief and ImSPEM cell lines resemble in vivo chief and SPEM cell lineages. These cell culture lines provide the first in vitro systems for studying the molecular mechanisms of the metaplastic transition in the stomach.

scholarly journals Tectorigenin Inhibits Glioblastoma Proliferation by G0/G1 Cell Cycle Arrest

Medicina ◽  
2020 ◽  
Vol 56 (12) ◽  
pp. 681
Author(s):  
Liang-Tsai Yeh ◽  
Li-Sung Hsu ◽  
Yi-Hsuan Chung ◽  
Chih-Jung Chen
Keyword(s):  
Cell Cycle ◽  
Cell Cycle Arrest ◽  
Molecular Mechanisms ◽  
In Vitro Models ◽  
Flavonoid Compound ◽  
G1 Phase ◽  
Glioblastoma Cells ◽  
Cycle Arrest ◽  
Dependent Protein

Background and objectives: Glioblastoma is one of the leading cancer-related causes of death of the brain region and has an average 5-year survival rate of less than 5%. The aim of this study was to investigate the effectiveness of tectorigenin, a naturally occurring flavonoid compound with anti-inflammatory, anti-oxidant, and anti-tumor properties, as a treatment for glioblastoma. A further goal was to use in vitro models to determine the underlying molecular mechanisms. Materials and Methods: Exposure to tectorigenin for 24 h dose-dependently reduced the viability of glioblastoma cells. Results: Significant cell cycle arrest at G0/G1 phase occurred in the presence of 200 and 300 µM tectorigenin. Treatment with tectorigenin clearly reduced the levels of phosphorylated retinoblastoma protein (p-RB) and decreased the expression of cyclin-dependent protein 4 (CDK4). Tectorigenin treatment also significantly enhanced the expression of p21, a CDK4 inhibitor. Conclusions: Collectively, our findings indicated that tectorigenin inhibited the proliferation of glioblastoma cells by cell cycle arrest at the G0/G1 phase.

scholarly journals Investigating materials and orientation parameters for the creation of a 3D musculoskeletal interface co-culture model

2020 ◽  
Vol 7 (4) ◽  
pp. 413-425
Author(s):  
Hamad Alsaykhan ◽  
Jennifer Z Paxton
Keyword(s):  
Cell Types ◽  
Bone Cell ◽  
In Vitro Models ◽  
Cellular Growth ◽  
Great Promise ◽  
Musculoskeletal Tissue ◽  
Form And Function ◽  
Horizontal Orientation ◽  
And Migration

Abstract Musculoskeletal tissue interfaces are a common site of injury in the young, active populations. In particular, the interface between the musculoskeletal tissues of tendon and bone is often injured and to date, no single treatment has been able to restore the form and function of damaged tissue at the bone–tendon interface. Tissue engineering and regeneration hold great promise for the manufacture of bespoke in vitro models or implants to be used to advance repair and so this study investigated the material, orientation and culture choices for manufacturing a reproducible 3D model of a musculoskeletal interface between tendon and bone cell populations. Such models are essential for future studies focussing on the regeneration of musculoskeletal interfaces in vitro. Cell-encapsulated fibrin hydrogels, arranged in a horizontal orientation though a simple moulding procedure, were shown to best support cellular growth and migration of cells to form an in vitro tendon–bone interface. This study highlights the importance of acknowledging the material and technical challenges in establishing co-cultures and suggests a reproducible methodology to form 3D co-cultures between tendon and bone, or other musculoskeletal cell types, in vitro.

scholarly journals EWSR1-WT1 Target Genes and Therapeutic Options Identified in a Novel DSRCT In Vitro Model

Cancers ◽  
2021 ◽  
Vol 13 (23) ◽  
pp. 6072
Author(s):  
Margit Bleijs ◽  
Corine Pleijte ◽  
Sem Engels ◽  
Femke Ringnalda ◽  
Friederike Meyer-Wentrup ◽  
...  
Keyword(s):  
Therapeutic Target ◽  
In Vitro Model ◽  
Molecular Mechanisms ◽  
Target Genes ◽  
Treatment Options ◽  
Chromosomal Translocation ◽  
In Vitro Models ◽  
Therapeutic Options ◽  
Vitro Model

Desmoplastic small round cell tumor (DSRCT) is a rare and aggressive soft tissue sarcoma with a lack of effective treatment options and a poor prognosis. DSRCT is characterized by a chromosomal translocation, resulting in the EWSR1-WT1 gene fusion. The molecular mechanisms driving DSRCT are poorly understood, and a paucity of preclinical models hampers DSRCT research. Here, we establish a novel primary patient-derived DSRCT in vitro model, recapitulating the original tumor. We find that EWSR1-WT1 expression affects cell shape and cell survival, and we identify downstream target genes of the EWSR1-WT1 fusion. Additionally, this preclinical in vitro model allows for medium-throughput drug screening. We discover sensitivity to several drugs, including compounds targeting RTKs. MERTK, which has been described as a therapeutic target for several malignancies, correlates with EWSR1-WT1 expression. Inhibition of MERTK with the small-molecule inhibitor UNC2025 results in reduced proliferation of DSRCT cells in vitro, suggesting MERTK as a therapeutic target in DSRCT. This study underscores the usefulness of preclinical in vitro models for studying molecular mechanisms and potential therapeutic options.

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