Observations on chick-embryo lens histogenesis in vivo and in vitro

1974 ◽  
Vol 52 (3) ◽  
pp. 345-352 ◽  
Author(s):  
Brian G. McLean ◽  
Cyril V. Finnegan
Keyword(s):  
Chick Embryo ◽  
Cell Elongation ◽  
Fiber Cell ◽  
Cell Extension ◽  
Differentiated Cells ◽  
Cytoplasmic Organization ◽  
Extensive Cell ◽  
Cytoplasmic Differentiation

The 6-day chick-embryo lens anterior epithelium will undergo histogenesis in vitro. A 'normal' epithelial curvature in vitro is required for extensive fiber-cell elongation; a reversed curvature, or flat epithelial conformation, results in considerably reduced cell extension. With a 'normal' epithelial curvature, cell elongation in vitro progresses rapidly for about 3 days, and changes in cytoplasmic organization (ultrastructure) take place that are similar to those associated with fiber-cell differentiation in vivo. However, these cells do not achieve as full a cytoplasmic differentiation as was observed in the most differentiated cells of the normal embryonic lens. Epithelia explanted with a reversed curvature, while evidencing reduced cell elongation, had, after 3 days in vitro, differentiated (according to criteria of ultrastructure and relative proportions of soluble proteins) in a manner similar to those epithelia explanted with a 'normal' curvature and in which extensive cell elongation had been demonstrated.

Differentiation of kidney antigens in the human foetus

Development ◽  
1969 ◽  
Vol 21 (3) ◽  
pp. 517-537
Author(s):  
Ewert Linder
Keyword(s):  
Chick Embryo ◽  
Specific Antigen ◽  
Mouse Kidney ◽  
Human Foetus ◽  
Specific Antigens ◽  
Number Of Authors

The appearance of new antigens in the embryo during differentiation has been investigated by a number of authors. Among the proteins studied were myosin (Holtzer, 1961; Ebert, 1962), Jens crystallin (Ten Cate & Van Doorenmaalen, 1950), chick embryo haemoglobin (Wilt, 1962), and keratin during feather formation in chick embryo (Ben-Or & Bell, 1965). The development of liver proteins in the chick embryo was studied by D'Amelio, Mutolo & Piazza (1963). Okada & Sato (1963) and Okada (1965) studied the appearance of a ‘kidney-specific’ antigen in the developing mesonephros. Lahti & Saxen (1966) demonstrated the appearance of mouse kidney-specific tubule antigens during development both in vivo and in vitro. ‘Kidney-specific’ antigens are found in the metanephric proximal secreting tubules of various mammals (Hill & Cruickshank, 1953; Weiler, 1956; Groupe & Kaplan, 1967; Nairn, Ghose & Maxwell, 1967), including man (Nairn, Ghose, Fothergill & McEntegart, 1962), and in the mesonephric tubules of birds.

Mode of action of amphotericin B on chick embryo fibroblasts and on mouse Ehrlich tumour cells: a cytological and cytochemical analysis

1975 ◽  
Vol 18 (3) ◽  
pp. 441-451
Author(s):  
F. De Paermentier ◽  
R. Bassleer ◽  
A. Lepoint ◽  
C. Desaive ◽  
G. Goessens ◽  
...  
Keyword(s):  
Chick Embryo ◽  
Amphotericin B ◽  
Tumour Cells ◽  
Total Protein Content ◽  
Cell Multiplication ◽  
Cytochemical Analysis ◽  
Ehrlich Ascites ◽  
Embryo Fibroblasts

Chick embryo fibroblasts cultivated in vitro and Ehrlich ascites tumor cells (in vivo or in vitro) have been treated with amphotericin B. Cell multiplication is strongly inhibited. Large clear zones appear in the fibroblast nucleoi (phase-contrast and electron-microscope observations). Many treated fibroblasts and tumour cells have a high DNA content (pre-mitotic or polyploid level; measurements by cytophotometry). However, the RNA content (cytophotometry) and the total protein content (cytophotometry and micro-interferometry) are relatively low in the tumour cells. As shown by autoradiography, DNA synthesis is active but RNA synthesis and, in some cases, protein synthesis are inhibited. Due to this unbalanced growth, the cells cannot divide.

Tissue specificity of type I collagen gene expression is determined at both transcriptional and post-transcriptional levels

1984 ◽  
Vol 4 (9) ◽  
pp. 1843-1852
Author(s):  
R J Focht ◽  
S L Adams
Keyword(s):  
Gene Expression ◽  
Rna Structure ◽  
Type I Collagen ◽  
Translational Efficiency ◽  
Type I ◽  
Collagen Gene ◽  
Differentiated Cells ◽  
Collagen Gene Expression

We analyzed the control of type I collagen synthesis in four kinds of differentiated cells from chicken embryos which synthesize very different amounts of the protein. Tendon, skin, and smooth muscle cells were found to have identical amounts of type I collagen RNAs; however, the RNAs had inherently different translatabilities, which were observed both in vivo and in vitro. Chondrocytes also had substantial amounts of type I collagen RNAs, even though they directed no detectable synthesis of the protein either in vivo or in vitro. Type I collagen RNAs in chondrocytes display altered electrophoretic mobilities, suggesting that in these cells the reduction in translational efficiency may be mediated in part by changes in the RNA structure. These data indicate that control of type I collagen gene expression is a complex process which is exerted at both transcriptional and post-transcriptional levels.

scholarly journals Isolation and characterization of adrenocortical progenitors involved in the adaptation to stress

2018 ◽  
Vol 115 (51) ◽  
pp. 12997-13002 ◽  
Author(s):  
Charlotte Steenblock ◽  
Maria F. Rubin de Celis ◽  
Luis F. Delgadillo Silva ◽  
Verena Pawolski ◽  
Ana Brennand ◽  
...  
Keyword(s):  
Lineage Tracing ◽  
Differentiated Cells ◽  
Isolation And Characterization ◽  
Proliferation And Differentiation ◽  
Response To Stress ◽  
Steroidogenic Cells ◽  
High Degree

The adrenal gland is a master regulator of the human body during response to stress. This organ shows constant replacement of senescent cells by newly differentiated cells. A high degree of plasticity is critical to sustain homeostasis under different physiological demands. This is achieved in part through proliferation and differentiation of adult adrenal progenitors. Here, we report the isolation and characterization of a Nestin+ population of adrenocortical progenitors located under the adrenal capsule and scattered throughout the cortex. These cells are interconnected with progenitors in the medulla. In vivo lineage tracing revealed that, under basal conditions, this population is noncommitted and slowly migrates centripetally. Under stress, this migration is greatly enhanced, and the cells differentiate into steroidogenic cells. Nestin+ cells cultured in vitro also show multipotency, as they differentiate into mineralocorticoid and glucocorticoid-producing cells, which can be further influenced by the exposure to Angiotensin II, adrenocorticotropic hormone, and the agonist of luteinizing hormone-releasing hormone, triptorelin. Taken together, Nestin+ cells in the adult adrenal cortex exhibit the features of adrenocortical progenitor cells. Our study provides evidence for a role of Nestin+ cells in organ homeostasis and emphasizes their role under stress. This cell population might be a potential source of cell replacement for the treatment of adrenal insufficiency.

The in vitro effect of the nerve growth factor on chick embryo spinal ganglia—a light-microscopic evaluation

Development ◽  
1970 ◽  
Vol 24 (2) ◽  
pp. 381-392
Author(s):  
Peddrick Weis
Keyword(s):  
Nerve Growth Factor ◽  
Growth Factor ◽  
Chick Embryo ◽  
Culture Period ◽  
Spinal Ganglia ◽  
Nerve Growth ◽  
Microscopic Evaluation ◽  
Vitro Effect

The effect of the nerve growth factor (NGF) on chick embryo spinal ganglia was studied in the hanging-drop bioassay system by comparison with parallel development in vivo. The well-differentiated ventrolateral neuroblasts, which in vivo increase 1·33 times in size during the culture period, did not increase in size at all in vitro. Only 65–72% survived to the end of the culture period regardless of the NGF concentration. The less-differentiated mediodorsal (M-D) neuroblasts, which in vivo increase 1·31 times in size during the culture period, were found to increase equally in vitro if sufficient NGF was present. Such a quantity was greater than that which evoked maximum outgrowth of neurites. Survival of M-D neuroblasts was also related to NGF concentration but did not equal the in vivo condition even at the highest concentration. The hyperchromatic type of degeneration prevented by high NGF concentrations is that which results in vivo from insufficient peripheral field. From this and other reports it would appear that the response to NGF seen in vitro is due only to the M-D neuroblasts, and that all biochemical and cytological observations which have been reported would therefore represent conditions within those cells only.

Interactions between mesoderm cells and the extracellular matrix following gastrulation in the chick embryo

1991 ◽  
Vol 99 (2) ◽  
pp. 431-441
Author(s):  
A.J. Brown ◽  
E.J. Sanders
Keyword(s):  
Extracellular Matrix ◽  
Chick Embryo ◽  
Basement Membrane ◽  
Primitive Streak ◽  
Cell Binding ◽  
Fab Fragment ◽  
Fibronectin Receptor ◽  
In Vitro Methods

In the gastrulating chick embryo, the mesoderm cells arise from the epiblast layer by ingression through the linear accumulation of cells called the primitive streak. The mesoderm cells emerge from the streak with a fibroblastic morphology and proceed to move away from the mid-line of the embryo using, as a substratum, the basement membrane of the overlying epiblast and the extracellular matrix. We have investigated the roles of fibronectin and laminin as putative substrata for mesoderm cells using complementary in vivo and in vitro methods. We have microinjected agents into the tissue space adjacent to the primitive streak of living embryos and, after further incubation, we have examined the embryos for perturbation of the mesoderm tissue. These agents were: cell-binding regions from fibronectin (RGDS) and laminin (YIGSR), antibodies to these glycoproteins, and a Fab' fragment of the antibody to fibronectin. We find that RGDS, antibody to fibronectin, and the Fab' fragment cause a decrease in the number of mesoderm cells spread on the basement membrane, and a perturbation of cell shape suggesting locomotory impairment. No such influence was seen with YIGSR or antibodies to laminin. These results were extended using in vitro methods in which mesoderm cells were cultured in fibronectin-free medium on fibronectin or laminin in the presence of various agents. These agents were: RGDS; YIGSR; antibodies to fibronectin, fibronectin receptor, laminin and vitronectin; and a Fab' fragment of the fibronectin antiserum. We find that cell attachment and spreading on fibronectin is impaired by RGDS, antiserum to fibronectin, the Fab' fragment of fibronectin antiserum, and antiserum to fibronectin receptor. The results suggest that although the RGDS site in fibronectin is important, it is probably not the only fibronectin cell-binding site involved in mediating the behaviour of the mesoderm cells. Cells growing on laminin were perturbed by YIGSR, RGDS and antibodies to laminin, suggesting that mesoderm cells are able to recognise at least two sites in the laminin molecule. We conclude that the in vivo dependence of mesoderm cells on fibronectin is confirmed, but that although these cells have the ability to recognise sites in laminin as mediators of attachment and spreading, the in vivo role of this molecule in mesoderm morphogenesis is not yet certain.

scholarly journals Detection of breakpoint cluster region- negative and nonclonal hematopoiesis in vitro and in vivo after transplantation of cells selected in cultures of chronic myeloid leukemia marrow

Blood ◽  
1990 ◽  
Vol 76 (11) ◽  
pp. 2404-2410 ◽  
Author(s):  
AG Turhan ◽  
RK Humphries ◽  
CJ Eaves ◽  
MJ Barnett ◽  
GL Phillips ◽  
...  
Keyword(s):  
Chronic Myeloid Leukemia ◽  
Myeloid Leukemia ◽  
Hematopoietic Cells ◽  
Breakpoint Cluster Region ◽  
Cluster Region ◽  
Differentiated Cells ◽  
The One

Abstract Philadelphia (Ph1) chromosome-positive clonogenic progenitors usually disappear within 4 to 6 weeks in long-term cultures established from the marrow of patients with chronic myeloid leukemia (CML). In contrast, coexisting chromosomally normal hematopoietic cells are relatively well maintained. Thus, even though normal cells are initially undetectable, they may become the predominant population. Recently, we have begun to explore the potential of such cultures as a strategy for preparing CML marrow for autografting, and based on cytogenetic studies of the differential kinetics of Ph1-positive and Ph1-negative clonogenic cells, have chosen a 10-day period in culture to obtain maximal numbers of selectively enriched normal stem cells. Here we present the results of molecular analyses of the cells regenerated in vivo for the initial three CML patients to be treated using this approach by comparison with the differentiated cells generated by continued maintenance of an aliquot of the autograft in vitro (using a slightly modified culture feeding procedure to enhance the production and release of cells into the nonadherent fraction after 4 weeks) for the one patient whose genotype made molecular analysis of clonality status also possible. These analyses showed that cells with a rearranged breakpoint cluster region (BCR) gene were not detectable by Southern blotting in either in vitro or in vivo populations of mature cells that might be assumed to represent the progeny of primitive cells present at the end of the initial 10 days in culture. Production of BCR- negative cells was also shown to be temporally correlated with the appearance of nonclonal hematopoietic cells both in culture and in vivo. These findings provide support for the view that prolonged maintenance of CML marrow cells in long-term culture may allow molecular characterization of both the BCR-genotype and clonality status of cells with in vivo regenerative potential.

scholarly journals In vitro neuroprotective activities of two distinct probiotic consortia

2019 ◽  
Vol 10 (4) ◽  
pp. 437-447 ◽  
Author(s):  
D.R. Michael ◽  
T.S. Davies ◽  
K.E. Loxley ◽  
M.D. Allen ◽  
M.A. Good ◽  
...  
Keyword(s):  
Cell Model ◽  
Neuronal Cell ◽  
In Vivo Studies ◽  
Intact Cells ◽  
Bacterial Consortia ◽  
Differentiated Cells ◽  
Genes Encoding ◽  
Induced Apoptosis

Neurodegeneration has been linked to changes in the gut microbiota and this study compares the neuroprotective capability of two bacterial consortia, known as Lab4 and Lab4b, using the established SH-SY5Y neuronal cell model. Firstly, varying total antioxidant capacities (TAC) were identified in the intact cells from each consortia and their secreted metabolites, referred to as conditioned media (CM). 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) and Crystal Violet (CV) assays of cell viability revealed that Lab4 CM and Lab4b CM could induce similar levels of proliferation in SH-SY5Y cells and, despite divergent TAC, possessed a comparable ability to protect undifferentiated and retinoic acid-differentiated cells from the cytotoxic actions of rotenone and undifferentiated cells from the cytotoxic actions of 1-methyl-4-phenylpyridinium iodide (MPP+). Lab4 CM and Lab4b CM also had the ability to attenuate rotenone-induced apoptosis and necrosis with Lab4b inducing the greater effect. Both consortia showed an analogous ability to attenuate intracellular reactive oxygen species accumulation in SH-SY5Y cells although the differential upregulation of genes encoding glutathione reductase and superoxide dismutase by Lab4 CM and Lab4b CM, respectively, implicates the involvement of consortia-specific antioxidative mechanisms of action. This study implicates Lab4 and Lab4b as potential neuroprotective agents and justifies their inclusion in further in vivo studies.

scholarly journals Requirement for Down-Regulation of the CCAAT-binding Activity of the NF-Y Transcription Factor during Skeletal Muscle Differentiation

2003 ◽  
Vol 14 (7) ◽  
pp. 2706-2715 ◽  
Author(s):  
Aymone Gurtner ◽  
Isabella Manni ◽  
Paola Fuschi ◽  
Roberto Mantovani ◽  
Fiorella Guadagni ◽  
...  
Keyword(s):  
Skeletal Muscle ◽  
Muscle Cells ◽  
Cyclin B1 ◽  
Binding Activity ◽  
Down Regulation ◽  
Cardiac Muscle Cells ◽  
Differentiated Cells ◽  
Target Promoters

NF-Y is composed of three subunits, NF-YA, NF-YB, and NF-YC, all required for DNA binding. All subunits are expressed in proliferating skeletal muscle cells, whereas NF-YA alone is undetectable in terminally differentiated cells in vitro. By immunohistochemistry, we show that the NF-YA protein is not expressed in the nuclei of skeletal and cardiac muscle cells in vivo. By chromatin immunoprecipitation experiments, we demonstrate herein that NF-Y does not bind to the CCAAT boxes of target promoters in differentiated muscle cells. Consistent with this, the activity of these promoters is down-regulated in differentiated muscle cells. Finally, forced expression of the NF-YA protein in cells committed to differentiate leads to an impairment in the down-regulation of cyclin A, cyclin B1, and cdk1 expression and is accompanied by a delay in myogenin expression. Thus, our results indicate that the suppression of NF-Y function is of crucial importance for the inhibition of several cell cycle genes and the induction of the early muscle-specific program in postmitotic muscle cells.

scholarly journals COMPARATIVE STUDIES IN ROUS SARCOMA WITH VIRUS, TUMOR CELLS, AND CHICK EMBRYO CELLS TRANSFORMED IN VITRO BY VIRUS

1962 ◽  
Vol 115 (1) ◽  
pp. 245-251 ◽  
Author(s):  
Robert M. Dougherty ◽  
Herbert R. Morgan
Keyword(s):  
Chick Embryo ◽  
Tumor Cells ◽  
Comparative Studies ◽  
Rous Sarcoma Virus ◽  
Rous Sarcoma ◽  
Transformed Fibroblasts ◽  
Embryo Cells ◽  
Sarcoma Virus

Chick embryo fibroblasts infected in vitro with Rous sarcoma virus have properties similar to tumor cells when injected into virus-immune chickens. When such virus-transformed fibroblasts are injected into normal chickens, they apparently participate in the production of tumors independent of their release of virus and are thus apparently malignant in vivo.

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