Meiotic Chromosome Synapsis and XY-Body Formation In Vitro

To achieve spermatogenesis in vitro, one of the most challenging processes to mimic is meiosis. Meiotic problems, like incomplete synapsis of the homologous chromosomes, or impaired homologous recombination, can cause failure of crossover formation and subsequent chromosome nondisjunction, eventually leading to aneuploid sperm. These meiotic events are therefore strictly monitored by meiotic checkpoints that initiate apoptosis of aberrant spermatocytes and lead to spermatogenic arrest. However, we recently found that, in vitro derived meiotic cells proceeded to the first meiotic division (MI) stage, despite displaying incomplete chromosome synapsis, no discernible XY-body and lack of crossover formation. We therefore optimized our in vitro culture system of meiosis from male germline stem cells (mGSCs) in order to achieve full chromosome synapsis, XY-body formation and meiotic crossovers. In comparison to previous culture system, the in vitro-generated spermatocytes were transferred after meiotic initiation to a second culture dish. This dish already contained a freshly plated monolayer of proliferatively inactivated immortalized Sertoli cells supporting undifferentiated mGSCs. In this way we aimed to simulate the multiple layers of germ cell types that support spermatogenesis in vivo in the testis. We found that in this optimized culture system, although independent of the undifferentiated mGSCs, meiotic chromosome synapsis was complete and XY body appeared normal. However, meiotic recombination still occurred insufficiently and only few meiotic crossovers were formed, leading to MI-spermatocytes displaying univalent chromosomes (paired sister chromatids). Therefore, considering that meiotic checkpoints are not necessarily fully functional in vitro, meiotic crossover formation should be closely monitored when mimicking gametogenesis in vitro to prevent generation of aneuploid gametes.

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Adipose and Muscle Cell Co-Culture System: A Novel In Vitro Tool to Mimic the In Vivo Cellular Environment

Biology ◽

10.3390/biology10010006 ◽

2020 ◽

Vol 10 (1) ◽

pp. 6

Author(s):

Palaniselvam Kuppusamy ◽

Dahye Kim ◽

Ilavenil Soundharrajan ◽

Inho Hwang ◽

Ki Choon Choi

Keyword(s):

Drug Development ◽

Culture System ◽

Cell Types ◽

Culture Cell ◽

In Vitro Techniques ◽

Culture Systems ◽

Complex Interactions ◽

Cellular Environment

A co-culture system allows researchers to investigate the complex interactions between two cell types under various environments, such as those that promote differentiation and growth as well as those that mimic healthy and diseased states, in vitro. In this paper, we review the most common co-culture systems for myocytes and adipocytes. The in vitro techniques mimic the in vivo environment and are used to investigate the causal relationships between different cell lines. Here, we briefly discuss mono-culture and co-culture cell systems and their applicability to the study of communication between two or more cell types, including adipocytes and myocytes. Also, we provide details about the different types of co-culture systems and their applicability to the study of metabolic disease, drug development, and the role of secretory factors in cell signaling cascades. Therefore, this review provides details about the co-culture systems used to study the complex interactions between adipose and muscle cells in various environments, such as those that promote cell differentiation and growth and those used for drug development.

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MO684A CO-CULTURE MODEL FOR TESTING EFFECTS OF CYTOPROTECTIVE ADDITIVES IN PD FLUIDS ON THE SECRETOME OF MESOTHELIAL AND ENDOTHELIAL CELLS

Nephrology Dialysis Transplantation ◽

10.1093/ndt/gfab101.006 ◽

2021 ◽

Vol 36 (Supplement_1) ◽

Author(s):

Juan Manuel Sacnun ◽

Rebecca Herzog ◽

Klaus Kratochwill

Keyword(s):

Endothelial Cells ◽

Cardiovascular Risk ◽

Culture System ◽

Molecular Mechanisms ◽

Cell Types ◽

Cell Junctions ◽

Peptide Ligand ◽

Peritoneal Membrane

Abstract Background and Aims The composition of all currently available peritoneal dialysis fluids (PDF) triggers morphological and functional changes in the peritoneal membrane. Periodic exposure leads to vasculopathy, hypervascularization, and diabetes-like damage of vessels of the peritoneal membrane, eventually leading to technique failure. Patients undergoing dialysis generally, have a high risk of cardiovascular events. It is currently unclear if there is a mechanistic link between peritoneal membrane failure and cardiovascular risk. In vitro and in vivo studies have shown that cytoprotective additives (e.g. dipeptide alanyl-glutamine (AlaGln) or kinase inhibitor lithium chloride (LiCl)) to PDF reduce peritoneal damage. Here, we developed an experimental model for investigating effects of such additives on secretome-mediated signalling between cell-types of the peritoneal membrane which are relevant in the cardiovascular context. Method For modelling the peritoneal membrane in vitro, mesothelial (MC) and endothelial cells (EC) were co-cultured in transwell plates. MC were grown in the upper compartment and primary microvascular cells were grown in the lower compartment. MC were exposed to PDF with or without cytoprotective compounds (8 mM AlaGln in glucose-based PDF 3.86% or 10 mM LiCl in icodextrin-based PDF), while EC below were kept in medium. Cell damage was assessed by quantification of lactate-dehydrogenase (LDH) release, neutral red uptake and cell morphology. Proteome and secretome profiles were analysed for both cell-types in co-culture or separately with an isobaric-tag labelling approach with a multiplexed liquid chromatography/mass spectrometry (LC-MS) approach. Prior to analysis of the secretome a bead-based equalizer approach based on a combinatorial peptide ligand library (CPLL) was performed to enrich low abundant proteins. Results EC injury after PD-fluid exposure of MC was decreased with the addition of AlaGln or LiCl, showing a link between the individual cell outcomes. Proteome analysis revealed perturbation of major cellular processes including regulation of cell death and cytoskeleton re-organization, which characterize PDF cytotoxicity. Selected markers of angiogenesis, oxidative stress, cell junctions and transdifferentiation were counter-regulated by the additives. Co-cultured cells yielded differently regulated pathways following PDF exposure compared to separate culture. We were able to identify and quantify 334 secreted proteins in the co-culture system. The secretome analysis showed variation in several clinically relevant proteins and important extracellular processes such as extracellular matrix reorganization, vesicle transport or collagen deposition. Comparison to previously published abundance profiles of omental arteriolar proteins from paediatric PD patient and age-matched controls confirmed overlapping protein regulation between endothelial cells in vitro and in vivo. Conclusion This study shows that harmful effects of PDF-stressed MC also affect EC and elucidates potential mechanisms by which cytoprotective additives may counteract the signalling axis between local peritoneal damage and systemic vasculopathy. An in vitro co-culture system may be an attractive approach to simulate the close proximity of different cell types in the peritoneal membrane for testing direct and indirect effects of cytoprotective additives. Characterisation of PD-induced perturbations may allow identifying molecular mechanisms linking the peritoneal and cardiovascular context, offering therapeutic targets to reduce current limitations of PD and ultimately decreasing cardiovascular risk of dialysis patients.

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Ultrastructural observations on the in vitro cytoadherence of Plasmodium falciparum infected red blood cells

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100162132 ◽

1990 ◽

Vol 48 (3) ◽

pp. 914-915

Author(s):

D.J.P. Ferguson ◽

A.R. Berendt ◽

J. Tansey ◽

K. Marsh ◽

C.I. Newbold

Keyword(s):

Plasmodium Falciparum ◽

Red Blood Cells ◽

Blood Cells ◽

Umbilical Vein ◽

Cell Types ◽

Amelanotic Melanoma ◽

Cytoplasmic Process ◽

Umbilical Vein Endothelial Cells

In human malaria, the most serious clinical manifestation is cerebral malaria (CM) due to infection with Plasmodium falciparum. The pathology of CM is thought to relate to the fact that red blood cells containing mature forms of the parasite (PRBC) cytoadhere or sequester to post capillary venules of various tissues including the brain. This in vivo phenomenon has been studied in vitro by examining the cytoadherence of PRBCs to various cell types and purified proteins. To date, three Ijiost receptor molecules have been identified; CD36, ICAM-1 and thrombospondin. The specific changes in the PRBC membrane which mediate cytoadherence are less well understood, but they include the sub-membranous deposition of electron-dense material resulting in surface deformations called knobs. Knobs were thought to be essential for cytoadherence, lput recent work has shown that certain knob-negative (K-) lines can cytoadhere. In the present study, we have used electron microscopy to re-examine the interactions between K+ PRBCs and both C32 amelanotic melanoma cells and human umbilical vein endothelial cells (HUVEC).We confirm previous data demonstrating that C32 cells possess numerous microvilli which adhere to the PRBC, mainly via the knobs (Fig. 1). In contrast, the HUVEC were relatively smooth and the PRBCs appeared partially flattened onto the cell surface (Fig. 2). Furthermore, many of the PRBCs exhibited an invagination of the limiting membrane in the attachment zone, often containing a cytoplasmic process from the endothelial cell (Fig. 2).

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Epithelial Organotypic Cultures: A Viable Model to Address Mechanisms of Carcinogenesis by Epitheliotropic Viruses

Current Topics in Medicinal Chemistry ◽

10.2174/1568026618666180410125850 ◽

2018 ◽

Vol 18 (4) ◽

pp. 246-255 ◽

Cited By ~ 1

Author(s):

Lara Termini ◽

Enrique Boccardo

Keyword(s):

Three Dimensional ◽

Cell Types ◽

Experimental Models ◽

Biological Research ◽

Specific Gene ◽

Specific Cell ◽

Organotypic Cultures ◽

Skin Physiology

In vitro culture of primary or established cell lines is one of the leading techniques in many areas of basic biological research. The use of pure or highly enriched cultures of specific cell types obtained from different tissues and genetics backgrounds has greatly contributed to our current understanding of normal and pathological cellular processes. Cells in culture are easily propagated generating an almost endless source of material for experimentation. Besides, they can be manipulated to achieve gene silencing, gene overexpression and genome editing turning possible the dissection of specific gene functions and signaling pathways. However, monolayer and suspension cultures of cells do not reproduce the cell type diversity, cell-cell contacts, cell-matrix interactions and differentiation pathways typical of the three-dimensional environment of tissues and organs from where they were originated. Therefore, different experimental animal models have been developed and applied to address these and other complex issues in vivo. However, these systems are costly and time consuming. Most importantly the use of animals in scientific research poses moral and ethical concerns facing a steadily increasing opposition from different sectors of the society. Therefore, there is an urgent need for the development of alternative in vitro experimental models that accurately reproduce the events observed in vivo to reduce the use of animals. Organotypic cultures combine the flexibility of traditional culture systems with the possibility of culturing different cell types in a 3D environment that reproduces both the structure and the physiology of the parental organ. Here we present a summarized description of the use of epithelial organotypic for the study of skin physiology, human papillomavirus biology and associated tumorigenesis.

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Heme Oxygenase-1 Deficiency and Oxidative Stress: A Review of 9 Independent Human Cases and Animal Models

International Journal of Molecular Sciences ◽

10.3390/ijms22041514 ◽

2021 ◽

Vol 22 (4) ◽

pp. 1514 ◽

Cited By ~ 1

Author(s):

Akihiro Yachie

Keyword(s):

Oxidative Stress ◽

Animal Models ◽

Heme Oxygenase ◽

Inflammatory Diseases ◽

Cell Types ◽

Pharmacological Intervention ◽

Heme Oxygenase 1 ◽

Inflammatory Reactions

Since Yachie et al. reported the first description of human heme oxygenase (HO)-1 deficiency more than 20 years ago, few additional human cases have been reported in the literature. A detailed analysis of the first human case of HO-1 deficiency revealed that HO-1 is involved in the protection of multiple tissues and organs from oxidative stress and excessive inflammatory reactions, through the release of multiple molecules with anti-oxidative stress and anti-inflammatory functions. HO-1 production is induced in vivo within selected cell types, including renal tubular epithelium, hepatic Kupffer cells, vascular endothelium, and monocytes/macrophages, suggesting that HO-1 plays critical roles in these cells. In vivo and in vitro studies have indicated that impaired HO-1 production results in progressive monocyte dysfunction, unregulated macrophage activation and endothelial cell dysfunction, leading to catastrophic systemic inflammatory response syndrome. Data from reported human cases of HO-1 deficiency and numerous studies using animal models suggest that HO-1 plays critical roles in various clinical settings involving excessive oxidative stress and inflammation. In this regard, therapy to induce HO-1 production by pharmacological intervention represents a promising novel strategy to control inflammatory diseases.

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MyD88 Is Not Required for Muscle Injury-Induced Endochondral Heterotopic Ossification in a Mouse Model of Fibrodysplasia Ossificans Progressiva

Biomedicines ◽

10.3390/biomedicines9060630 ◽

2021 ◽

Vol 9 (6) ◽

pp. 630

Author(s):

Huili Lyu ◽

Cody M. Elkins ◽

Jessica L. Pierce ◽

C. Henrique Serezani ◽

Daniel S. Perrien

Keyword(s):

Heterotopic Ossification ◽

Muscle Injury ◽

Cell Types ◽

Fibrodysplasia Ossificans Progressiva ◽

Inflammatory Signaling ◽

Conditional Deletion ◽

Pathway Crosstalk ◽

Multiple Cell

Excess inflammation and canonical BMP receptor (BMPR) signaling are coinciding hallmarks of the early stages of injury-induced endochondral heterotopic ossification (EHO), especially in the rare genetic disease fibrodysplasia ossificans progressiva (FOP). Multiple inflammatory signaling pathways can synergistically enhance BMP-induced Smad1/5/8 activity in multiple cell types, suggesting the importance of pathway crosstalk in EHO and FOP. Toll-like receptors (TLRs) and IL-1 receptors mediate many of the earliest injury-induced inflammatory signals largely via MyD88-dependent pathways. Thus, the hypothesis that MyD88-dependent signaling is required for EHO was tested in vitro and in vivo using global or Pdgfrα-conditional deletion of MyD88 in FOP mice. As expected, IL-1β or LPS synergistically increased Activin A (ActA)-induced phosphorylation of Smad 1/5 in fibroadipoprogenitors (FAPs) expressing Alk2R206H. However, conditional deletion of MyD88 in Pdgfrα-positive cells of FOP mice did not significantly alter the amount of muscle injury-induced EHO. Even more surprisingly, injury-induced EHO was not significantly affected by global deletion of MyD88. These studies demonstrate that MyD88-dependent signaling is dispensable for injury-induced EHO in FOP mice.

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Modelling the Human Placental Interface In Vitro—A Review

Micromachines ◽

10.3390/mi12080884 ◽

2021 ◽

Vol 12 (8) ◽

pp. 884

Author(s):

Marta Cherubini ◽

Scott Erickson ◽

Kristina Haase

Keyword(s):

Drug Testing ◽

Cell Types ◽

In Vitro Models ◽

Placental Development ◽

Scientific Challenge ◽

Induced Pluripotent ◽

And Function ◽

And Control

Acting as the primary link between mother and fetus, the placenta is involved in regulating nutrient, oxygen, and waste exchange; thus, healthy placental development is crucial for a successful pregnancy. In line with the increasing demands of the fetus, the placenta evolves throughout pregnancy, making it a particularly difficult organ to study. Research into placental development and dysfunction poses a unique scientific challenge due to ethical constraints and the differences in morphology and function that exist between species. Recently, there have been increased efforts towards generating in vitro models of the human placenta. Advancements in the differentiation of human induced pluripotent stem cells (hiPSCs), microfluidics, and bioprinting have each contributed to the development of new models, which can be designed to closely match physiological in vivo conditions. By including relevant placental cell types and control over the microenvironment, these new in vitro models promise to reveal clues to the pathogenesis of placental dysfunction and facilitate drug testing across the maternal–fetal interface. In this minireview, we aim to highlight current in vitro placental models and their applications in the study of disease and discuss future avenues for these in vitro models.

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In vitro assessment of food-derived-glucose bioaccessibility and bioavailability in bicameral cell culture system

Turkish Journal of Biochemistry ◽

10.1515/tjb-2020-0082 ◽

2020 ◽

Vol 45 (5) ◽

pp. 631-637

Author(s):

Cansu Ozel-Tasci ◽

Gozde Pilatin ◽

Ozgur Edeer ◽

Sukru Gulec

Keyword(s):

Cell Culture ◽

Culture System ◽

Metabolic Diseases ◽

Enzymatic Digestion ◽

Cell Culture System ◽

Culture Studies ◽

Experimental Approaches ◽

In Vitro Assessment

AbstractBackgroundFunctional foods can help prevent metabolic diseases, and it is essential to evaluate functional characteristics of foods through in vitro and in vivo experimental approaches.ObjectiveWe aimed to use the bicameral cell culture system combined with the in vitro digestion to evaluate glucose bioavailability.Materials and methodsCake, almond paste, and pudding were modified by adding fiber and replacing sugar with sweeteners and polyols. Digestion process was modeled in test tubes. Rat enterocyte cells (IEC-6) were grown in a bicameral cell culture system to mimic the physiological characteristics of the human intestine. The glucose bioaccessibility and cellular glucose efflux were measured by glucose oxidase assay.Results and discussionThe glucose bioaccessibilities of modified foods were significantly lower (cake: 2.6 fold, almond paste: 9.2 fold, pudding 2.8 fold) than the controls. Cellular glucose effluxes also decreased in the modified cake, almond paste, and pudding by 2.2, 4, and 2 fold respectively compared to their controls.ConclusionOur results suggest that combining in vitro enzymatic digestion with cell culture studies can be a practical way to test in vitro glucose bioaccessibility and bioavailability in functional food development.

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Rho GTPases as Key Molecular Players within Intestinal Mucosa and GI Diseases

Cells ◽

10.3390/cells10010066 ◽

2021 ◽

Vol 10 (1) ◽

pp. 66

Author(s):

Rashmita Pradhan ◽

Phuong A. Ngo ◽

Luz d. C. Martínez-Sánchez ◽

Markus F. Neurath ◽

Rocío López-Posadas

Keyword(s):

Intestinal Mucosa ◽

Rho Gtpases ◽

Current Knowledge ◽

Cell Types ◽

Effector Proteins ◽

Special Focus ◽

Specific Cell ◽

Rho Proteins

Rho proteins operate as key regulators of the cytoskeleton, cell morphology and trafficking. Acting as molecular switches, the function of Rho GTPases is determined by guanosine triphosphate (GTP)/guanosine diphosphate (GDP) exchange and their lipidation via prenylation, allowing their binding to cellular membranes and the interaction with downstream effector proteins in close proximity to the membrane. A plethora of in vitro studies demonstrate the indispensable function of Rho proteins for cytoskeleton dynamics within different cell types. However, only in the last decades we have got access to genetically modified mouse models to decipher the intricate regulation between members of the Rho family within specific cell types in the complex in vivo situation. Translationally, alterations of the expression and/or function of Rho GTPases have been associated with several pathological conditions, such as inflammation and cancer. In the context of the GI tract, the continuous crosstalk between the host and the intestinal microbiota requires a tight regulation of the complex interaction between cellular components within the intestinal tissue. Recent studies demonstrate that Rho GTPases play important roles for the maintenance of tissue homeostasis in the gut. We will summarize the current knowledge on Rho protein function within individual cell types in the intestinal mucosa in vivo, with special focus on intestinal epithelial cells and T cells.

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Therapeutic Attributes of Endocannabinoid System against Neuro-Inflammatory Autoimmune Disorders

Molecules ◽

10.3390/molecules26113389 ◽

2021 ◽

Vol 26 (11) ◽

pp. 3389

Author(s):

Ishtiaq Ahmed ◽

Saif Ur Rehman ◽

Shiva Shahmohamadnejad ◽

Muhammad Anjum Zia ◽

Muhammad Ahmad ◽

...

Keyword(s):

Cannabinoid Receptors ◽

Cannabinoid Receptor ◽

Therapeutic Potential ◽

Endocannabinoid System ◽

Cell Types ◽

Autoimmune Disorders ◽

Specific Receptors ◽

Different Cell Types

In humans, various sites like cannabinoid receptors (CBR) having a binding affinity with cannabinoids are distributed on the surface of different cell types, where endocannabinoids (ECs) and derivatives of fatty acid can bind. The binding of these substance(s) triggers the activation of specific receptors required for various physiological functions, including pain sensation, memory, and appetite. The ECs and CBR perform multiple functions via the cannabinoid receptor 1 (CB1); cannabinoid receptor 2 (CB2), having a key effect in restraining neurotransmitters and the arrangement of cytokines. The role of cannabinoids in the immune system is illustrated because of their immunosuppressive characteristics. These characteristics include inhibition of leucocyte proliferation, T cells apoptosis, and induction of macrophages along with reduced pro-inflammatory cytokines secretion. The review seeks to discuss the functional relationship between the endocannabinoid system (ECS) and anti-tumor characteristics of cannabinoids in various cancers. The therapeutic potential of cannabinoids for cancer—both in vivo and in vitro clinical trials—has also been highlighted and reported to be effective in mice models in arthritis for the inflammation reduction, neuropathic pain, positive effect in multiple sclerosis and type-1 diabetes mellitus, and found beneficial for treating in various cancers. In human models, such studies are limited; thereby, further research is indispensable in this field to get a conclusive outcome. Therefore, in autoimmune disorders, therapeutic cannabinoids can serve as promising immunosuppressive and anti-fibrotic agents.

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