The effect of lipids on the subculture of differentiated cells from primary cultures of grasshopper embryonic tissues

1988 ◽  
Vol 24 (5) ◽  
pp. 388-400 ◽  
Author(s):  
Ronald H. Goodwin
Keyword(s):  
Primary Cultures ◽  
Embryonic Tissues ◽  
Differentiated Cells

scholarly journals N-myc proto-oncogene expression during organogenesis in the developing mouse as revealed by in situ hybridization.

1988 ◽  
Vol 107 (4) ◽  
pp. 1325-1335 ◽  
Author(s):  
G Mugrauer ◽  
F W Alt ◽  
P Ekblom
Keyword(s):  
In Situ Hybridization ◽  
Hair Follicles ◽  
Early Differentiation ◽  
Cell Lineages ◽  
Tissue Sections ◽  
Embryonic Tissues ◽  
Differentiated Cells ◽  
The Central Nervous System ◽  
Developing Kidney

The N-myc proto-oncogene is expressed during embryogenesis, suggesting that it plays a role in normal development. Since the myc-family oncogenes have been implicated in the control of cell growth, the embryonic expression may reflect rapid proliferation known to occur in development. Alternatively, N-myc expression may be involved in specific differentiation stages. In many embryonic tissues, early and late differentiation events occur in different locations. By in situ hybridization of tissue sections, we now demonstrate a restricted expression of N-myc mRNA to a few tissues and to areas where the first differentiation stages occur. N-myc expression was most strongly expressed in the developing kidney, hair follicles, and in various parts of the central nervous system. In these tissues, expression was restricted to a few cell lineages. In all lineages, expression was confined to early differentiation stages, and, at onset of overt differentiation, the level of expression decreased dramatically. Several rapidly proliferating tissues showed very little, if any, N-myc expression. In the brain, post-mitotic but not yet differentiated cells expressed high levels of N-myc mRNA. Therefore, N-myc expression is not a simple marker for proliferation in the embryo. Rather, N-myc expression seems to be a feature of early differentiation stages of some cell lineages in kidney, brain, and hair follicles, regardless of the proliferative status of the cell. The results raise the possibility that N-myc may participate in the control of these early differentiation events.

Isoenzyme transitions of creatine phosphokinase, aldolase and phosphoglycerate mutase in differentiating mouse cells

Development ◽  
1976 ◽  
Vol 35 (2) ◽  
pp. 355-367
Author(s):  
Eileen D. Adamson
Keyword(s):  
Creatine Phosphokinase ◽  
Phosphoglycerate Mutase ◽  
Embryonic Mouse ◽  
Embryonic Tissues ◽  
Differentiated Cells ◽  
Teratocarcinoma Cells ◽  
Mouse Tissues ◽  
Mouse Cells

Extracts of embryonic mouse tissues (skeletal, cardiac and smooth muscle, and brain) were analysed by Cellogel electrophoresis, for their isoenzymic distributions of three enzymes, creatine phosphokinase, aldolase and phosphoglycerate mutase. Embryonic tissues from the 12th day to the end of gestation were examined for isoenzyme transitions, and it was found that the adult forms of these enzymes appeared during gestation. Extracts from cloned teratocarcinoma cells were similarly examined in order to determine their degree of biochemical differentiation. Undifferentiated embryonal carcinoma cells contained only the early embryonic forms of all three enzymes, while differentiated cells formed in vivo, and in some cases in vitro, started to express the adult types of creatine phosphokinase and aldolase. Thus, biochemical parallels have been demonstrated between developing embryonic tissues and teratocarcinoma cells differentiating in vitro.

An axial gradient of transgene methylation in murine skeletal muscle: genomic imprint of rostrocaudal position

Development ◽  
1992 ◽  
Vol 116 (4) ◽  
pp. 1101-1112 ◽  
Author(s):  
M.J. Donoghue ◽  
B.L. Patton ◽  
J.R. Sanes ◽  
J.P. Merlie
Keyword(s):  
Cell Lines ◽  
Mammalian Cells ◽  
Skeletal Muscles ◽  
Body Position ◽  
Primary Cultures ◽  
The Body ◽  
Myogenic Cell ◽  
Methylation State ◽  
Differentiated Cells ◽  
Genomic Imprint

We previously used mice bearing a myosin light chain-chloramphenicol acetyltransferase (MLC1-CAT) transgene to show that adult muscle cells bear a heritable, cell autonomous memory of their rostrocaudal position. CAT mRNA and protein are expressed in a > 100-fold rostrocaudal gradient in skeletal muscles of developing and adult MLC1-CAT mice (Donoghue, M. J., Merlie, J. P., Rosenthal, N. and Sanes, J. R. (1991). Proc. Natl. Acad. Sci. USA 88, 5847–5851; Donoghue, M. J., Alvarez, J. D., Merlie, J. P. and Sanes, J. R. (1991). J. Cell Biol. 115, 423–434). Moreover, both in primary cultures and in myogenic cell lines prepared from individual muscles of these mice, CAT levels reflect the body position from which the myoblasts were derived (Donoghue, M.J., Morris-Valero, R., Johnson, Y.R., Merlie, J.P. and Sanes, J. R. (1992). Cell 69, 67–77). Here, we show that the methylation state of the MLC1-CAT transgene in skeletal muscles is also graded along the rostrocaudal axis: methylation levels decrease and expression levels increase in the order, jaw-->neck-->chest and forelimb-->hindlimb. Methylation levels are also approx. 10-fold higher in rostrally derived than in caudally derived myogenic cell lines, which express low and high levels of CAT, respectively. Within each cell line, undifferentiated cells (myoblasts), which do not express the transgene, and differentiated cells (myotubes), which do, are indistinguishable in methylation state. Thus, differentiation-related changes in transgene expression do not affect position-related levels of transgene methylation. On the other hand, treatment of rostrally derived lines with the demethylating agent, 5-azacytidine, decreases methylation and increases expression of the transgene. Thus, perturbation of methylation affects expression. Taken together, these results suggest that methylation provides a genomic imprint of rostrocaudal body position that may serve as a component of the positional memory that mammalian cells retain into adulthood.

MEIC Evaluation of Acute Systemic Toxicity

1996 ◽  
Vol 24 (1_part_1) ◽  
pp. 251-272 ◽  
Author(s):  
Cecilia Clemedson ◽  
Elisabeth McFarlane-Abdulla ◽  
Marianne Andersson ◽  
Frank A. Barile ◽  
Mabel C. Calleja ◽  
...  
Keyword(s):  
Full Range ◽  
Primary Cultures ◽  
In Vitro Cytotoxicity ◽  
Systemic Toxicity ◽  
Toxicity Tests ◽  
In Vitro Toxicity ◽  
Blood Concentrations ◽  
Differentiated Cells ◽  
Basal Cytotoxicity

The multicentre evaluation of in vitro cytotoxicity (MEIC) study is a programme designed to evaluate the relevance of in vitro toxicity tests for predicting human toxicity, and is organised by the Scandinavian Society for Cell Toxicology. The project started in 1989 and is scheduled to be finished by June 1996. MEIC is a voluntary effort by international laboratories to test the same 50 reference chemicals in their own in vitro toxicity systems. At present, 31 laboratories have submitted results for the first 30 reference chemicals from a total of 68 in vitro cytotoxicity tests. In the definitive evaluation of the MEIC programme, these in vitro results will be compared with human lethal blood concentrations and other relevant acute systemic toxicity data, and the results will be published as a series of articles. This paper, which is the first article in this series, describes and analyses the methodologies used in the 68 tests. The origins and purities of the test chemicals, the biological systems and the toxicity endpoints are also discussed. Since MEIC is not centrally directed, the selection of tests was entirely dependent on the preferences of the individual laboratories. Thus, the collection of tests is not representative of the full range of existing in vitro toxicity tests. In our study, basal cytotoxicity tests and ecotoxicological tests are prevalent, while tests for toxicity to primary cultures of differentiated cells, measured by organotypic toxicity endpoints, are clearly under-represented.

scholarly journals Expression patterns and different subcellular localization of the growth factors HDGF (hepatoma-derived growth factor) and HRP-3 (HDGF-related protein-3) suggest functions in addition to their mitogenic activity

2004 ◽  
Vol 378 (1) ◽  
pp. 169-176 ◽  
Author(s):  
Mekky M. ABOUZIED ◽  
Stephan L. BAADER ◽  
Frank DIETZ ◽  
Joachim KAPPLER ◽  
Volkmar GIESELMANN ◽  
...  
Keyword(s):  
Growth Factors ◽  
Growth Factor ◽  
Subcellular Localization ◽  
Single Cells ◽  
Expression Patterns ◽  
Primary Cultures ◽  
Brain Slices ◽  
Adult Brain ◽  
Differentiated Cells ◽  
C Terminus

HDGF (hepatoma-derived growth factor) and the HRPs (HDGF-related proteins) comprise a family of six proteins which display high identity in their N-terminus, but differ at the C-terminus. Here we investigate the patterns of expression of HDGF and HRP-3, by generating antisera specifically recognizing each growth factor. Whereas HRP-3 protein is expressed only in brain, HDGF can be found in a broad range of tissues, with highest levels in brain, testis, lung and spleen. The expression of HDGF and HRP-3 was found to be regulated during brain development, with highest levels around birth, followed by a decline until postnatal day 9. Interestingly, expression of HRP-3 increases again in adult brain. In situ hybridization and immunohistochemistry of cerebellar, cerebral and hippocampal brain slices showed that expression of both growth factors is not limited to areas of high proliferative activity. Both mRNAs and proteins are expressed in neuronal as well as glial cells. Immunocytochemistry of cultured neocortical neurons revealed that HDGF and HRP-3 can be found in the nucleus as well as the cytoplasm. HDGF is restricted to the neuronal soma, whereas HRP-3 can also be found in neurites. Thus the expression of HDGF and HRP-3 in differentiated cells, post-mitotic neurons and primary cultures of rat neocortex points to functions in brain that might not be limited to proliferation. In addition, their simultaneous expression in the same cell and their different subcellular localization in cultured neurons suggest different functions of HDGF and HRP-3 within single cells.

Expression of the asialoglycoprotein receptor in cultured rat hepatocytes is modulated by cell density

1996 ◽  
Vol 16 (6) ◽  
pp. 477-484 ◽  
Author(s):  
M. Massimi ◽  
L. Falasca ◽  
A. Felici ◽  
L. Dini ◽  
L. Conti Devirgiliis
Keyword(s):  
Cell Density ◽  
Primary Cultures ◽  
Rat Hepatocytes ◽  
Asialoglycoprotein Receptor ◽  
Receptor Expression ◽  
Transcriptional Level ◽  
Receptor System ◽  
Plating Density ◽  
Cellular Density ◽  
Differentiated Cells

The influence of cell density on expression of the asialoglycoprotein receptor system in primary cultures of rat hepatocytes was evaluated by measuring the level of the receptor specific mRNA. When the hepatocytes are cultured at high cellular density and are not in a proliferative condition, the transcript molecules of the receptor appear increased about 50% with respect to the low plating density, indicating a modulation of asialoglycoprotein receptor expression at transcriptional level. Such control may be dependent on surface molecules involved in cell specific reassociation, since it is well known that cell contacts play a significant regulatory role in differentiated cells.

scholarly journals Induction of differentiation in cultured rat and human podocytes.

1997 ◽  
Vol 8 (5) ◽  
pp. 697-705 ◽  
Author(s):  
P Mundel ◽  
J Reiser ◽  
W Kriz
Keyword(s):  
Primary Cultures ◽  
Growth Arrest ◽  
Culture Conditions ◽  
Phenotypic Changes ◽  
Differentiated Cells ◽  
Intermediate Phenotypes ◽  
Induction Of Differentiation ◽  
Cell Culture Conditions

Mature podocytes are highly differentiated cells that are unable to divide in vivo. During glomerulogenesis, podocytes develop from simple cuboidal cells into their adult phenotype, which is characterized by a complex pattern of processes. Cultivation of podocytes under standard conditions leads to dedifferentiation, including the loss of processes and of pp44, a marker of differentiated podocytes. In this study, the cell culture conditions for rat and human podocytes were modified by avoiding repeated subcultivation. This led to profound phenotypic changes in podocytes in vitro. The conversion of cobblestones into arborized cells was directly observed, and a series of intermediate phenotypes was documented. The cells converted within 3 wk from typical cobblestone appearance into individual arborized cells more closely resembling in vivo podocytes. Arborized cells were frequently binucleated and reached a size of up to 500 microns. Both cobblestone and arborized cells originated from podocytes, as evidenced by the expression of a podocyte-specific O-acetylated ganglioside and of the WT-1 protein. In contrast to primary cultures and early passages of cobblestones, a cloned rat podocyte cell line did not express WT-1 and could not be induced to differentiate into arborized cells. This finding indicates a role for WT-1 in maintaining differentiation of adult podocytes. The differentiation of arborized cells led to growth arrest and was reflected by the formation of processes and the expression of pp44 and desmin, which were never detected in cobblestones. It was concluded that partial differentiation of cultured podocytes can be achieved simply by avoiding repeated subcultivation, resulting in an arborized phenotype more closely reflecting in vivo podocytes.

Resistance of differentiated human airway epithelium to infection by rhinovirus

2004 ◽  
Vol 286 (2) ◽  
pp. L373-L381 ◽  
Author(s):  
N. Lopez-Souza ◽  
G. Dolganov ◽  
R. Dubin ◽  
L. A. Sachs ◽  
L. Sassina ◽  
...  
Keyword(s):  
Viral Infection ◽  
Airway Epithelium ◽  
Primary Cultures ◽  
Viral Rna ◽  
Human Airway ◽  
Human Airway Epithelium ◽  
Differentiated Cells ◽  
Poorly Differentiated ◽  
Well Differentiated

Virtually all in vitro studies of the effects of rhinovirus on human airway epithelium have used cells grown under conditions known to produce low levels of differentiation. The relevance of the results to native epithelium is questionable. Here we grew primary cultures of human tracheal or nasal epithelium under three conditions. One condition produced pseudostratified, mucociliary cells virtually indistinguishable from native epithelium. The other two conditions produced undifferentiated squamous cells lacking cilia. Cells were infected for 6 h with rhinovirus-16. After a 24-h incubation period, we determined levels of viral RNA in the cells, numbers of infectious viral particles released in the mucosal medium, expression of a variety of epithelial cytokines and other proteins, release of IL-6 and IL-8, and transepithelial electrical resistance and voltage. After infection, levels of viral RNA in the poorly differentiated cells were 30 or 130 times those in the differentiated. Furthermore, expression of mRNA for inflammatory cytokines, release of infectious particles, and release of IL-6 and IL-8 were closely correlated with the degree of viral infection. Thus well-differentiated cells are much more resistant to viral infection and its functional consequences than are poorly differentiated cells from the same source.

Sign in / Sign up

Export Citation Format

Share Document