Study of yolk-sac endoderm organogenesis in the chick using a specific enzyme (cysteine lyase) as a marker of cell differentiation

Development ◽  
1973 ◽  
Vol 29 (1) ◽  
pp. 159-174
Author(s):  
Nelly Bennett
Keyword(s):  
Cell Differentiation ◽  
Blood Cells ◽  
Primitive Streak ◽  
Yolk Sac ◽  
Specific Enzyme ◽  
Cell Proliferation And Differentiation ◽  
Lyase Activity ◽  
Morphological Specialization

The detection of a specific enzyme (cysteine lyase) of the yolk-sac endoderm by a very sensitive method is employed to characterize cell differentiation during the early stages of endoderm organogenesis in the chick. The first cells to contain active cysteine lyase are found in the germ wall at the primitive streak stage. In vivo observations establish a relation between the morphological specialization and organization of endodermal cells, their loss of mitotic activity and the increase in cysteine lyase activity. They suggest an influence of the mesoderm on endoderm differentiation. In vitro experiments confirm the existence in the yolk-sac endoderm of an incompatibility between cell proliferation and differentiation, as well as the action of the mesoderm on both the structural organization of the endoblast and the appearance of cysteine lyase; this last action seems to be due mainly to blood cells; chicken and rabbit blood cells are equally active. The problems of the origin of the endoderm and of the interactions occurring during the organogenesis of the yolk-sac endoderm are discussed.

Depletion in nuclear spermine during human spermatogenesis, a natural process of cell differentiation

1992 ◽  
Vol 263 (2) ◽  
pp. C343-C347 ◽  
Author(s):  
V. Quemener ◽  
Y. Blanchard ◽  
D. Lescoat ◽  
R. Havouis ◽  
J. P. Moulinoux
Keyword(s):  
Cell Proliferation ◽  
Cell Differentiation ◽  
Mammalian Cells ◽  
Gradient Centrifugation ◽  
Cell Nuclei ◽  
Cell Proliferation And Differentiation ◽  
Proliferation And Differentiation ◽  
Human Spermatogenesis

Polyamines (PA), polycations present in all mammalian cells, are essential for cell proliferation and differentiation. In vitro, PA are known to bind to DNA with a high affinity. In vivo, the intimate association of endogenous PA with highly condensed chromatin has been reported. During spermatogenesis, when processes of cell proliferation and differentiation take place, the potential role of polyamines has not been studied in depth. We report here the PA levels measured in human spermatogenic cell nuclei at different stages of differentiation. Cell populations (spermatocytes and round, elongating, or elongated spermatids) were obtained after submitting human testes to a trypsin-deoxyribonuclease digestion, then to a centrifugal elutriation and Percoll gradient centrifugation. A significant and progressive nuclear spermine level decrease was observed from primary spermatocytes to elongated spermatids. This release of spermine from nuclei was concomitant with three major events in mammalian spermiogenesis: the reduction of DNA transcription activity, the replacement of histone proteins by protamines, and the compaction of chromatin. This is the first report arguing a release of nuclear spermine during an in vivo physiological cell differentiation process.

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

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).

In-vitro- und In-vivo-Wirkung von Schilddrüsenhormon auf das Wachstum von Neuroblastomzellen

1990 ◽  
Vol 29 (03) ◽  
pp. 120-124
Author(s):  
R. P. Baum ◽  
E. Rohrbach ◽  
G. Hör ◽  
B. Kornhuber ◽  
E. Busse
Keyword(s):  
Cell Differentiation ◽  
Neuroblastoma Cells ◽  
Control Group ◽  
Initial Value ◽  
Initial Rise ◽  
Biphasic Effect ◽  
Contrast Microscopy ◽  
Morphological Sign

The effect of triiodothyronine (T3) on the differentiation of cultured neuroblastoma (NB) cells was studied after 9 days of treatment with a dose of 10-4 M/106 cells per day. Using phase contrast microscopy, 30-50% of NB cells showed formation of neurites as a morphological sign of cellular differentiation. The initial rise of the mitosis rate was followed by a plateau. Changes in cyclic nucleotide content, in the triphosphates and in the activity of the enzyme ornithine decarboxylase (ODC) were assessed in 2 human and 2 murine cell lines to serve as biochemical parameters of the cell differentiation induced by T3. Whereas the cAMP level increased significantly (3 to 7 fold compared with its initial value), the cGMP value dropped to 30 to 50% of that of the control group. ATP and GTP increased about 200%, the ODC showed a decrease of about 50%. The present studies show a biphasic effect of T3 on neuroblastoma cells: the initial rise of mitotic activity is followed by increased cell differentiation starting from day 4 of the treatment.

scholarly journals Multimodal Diagnostics of Microrheologic Alterations in Blood of Coronary Heart Disease and Diabetic Patients

Diagnostics ◽  
2021 ◽  
Vol 11 (1) ◽  
pp. 76
Author(s):  
Anastasia Maslianitsyna ◽  
Petr Ermolinskiy ◽  
Andrei Lugovtsov ◽  
Alexandra Pigurenko ◽  
Maria Sasonko ◽  
...  
Keyword(s):  
Coronary Heart Disease ◽  
Heart Disease ◽  
Red Blood Cells ◽  
Blood Cells ◽  
Optical Methods ◽  
Diabetic Patients ◽  
Aggregation Index ◽  
Significant Difference

Coronary heart disease (CHD) has serious implications for human health and needs to be diagnosed as early as possible. In this article in vivo and in vitro optical methods are used to study blood properties related to the aggregation of red blood cells in patients with CHD and comorbidities such as type 2 diabetes mellitus (T2DM). The results show not only a significant difference of the aggregation in patients compared to healthy people, but also a correspondence between in vivo and in vitro parameters. Red blood cells aggregate in CHD patients faster and more numerously; in particular the aggregation index increases by 20 ± 7%. The presence of T2DM also significantly elevates aggregation in CHD patients. This work demonstrates multimodal diagnostics and monitoring of patients with socially significant pathologies.

scholarly journals Inhibition of platelet phagocytosis as an in vitro predictor for therapeutic potential of RBC antibodies in murine ITP

Blood ◽  
2020 ◽  
Vol 135 (26) ◽  
pp. 2420-2424 ◽  
Author(s):  
Ramsha Khan ◽  
Melissa Menard ◽  
Chao-Ching Jen ◽  
Xi Chen ◽  
Peter A. A. Norris ◽  
...  
Keyword(s):  
Blood Cells ◽  
Immune Thrombocytopenia ◽  
Therapeutic Potential ◽  
Sufficient Condition ◽  
First Line ◽  
Phagocytosis Assay ◽  
First Line Therapy ◽  
Line Therapy

Abstract Polyclonal anti-D is a first-line therapy for immune thrombocytopenia (ITP). Monoclonal antibodies are desirable alternatives, but none have yet proven successful despite their ability to opsonize erythrocytes (or red blood cells, RBCs) and cause anemia. Here, we examined 12 murine erythrocyte–specific antibodies of different specificity and subtypes and found that 8 of these antibodies could induce anemia in antigen-positive mice. Of these 8 antibodies, only 5 ameliorated ITP. All antibodies were examined for their in vitro ability to support macrophage-mediated phagocytosis of erythrocytes. Antibodies which supported erythrocyte phagocytosis in vitro successfully ameliorated ITP in vivo. To examine the ability of each antibody to inhibit phagocytosis of platelets, the antibodies were used to sensitize erythrocytes in vitro and these were added to a platelet phagocytosis assay. Antibodies that inhibited platelet phagocytosis in vitro also all ameliorated ITP in vivo. We conclude that inducing anemia is not a sufficient condition for amelioration of ITP but that the antibody’s ability to prevent platelet phagocytosis in vitro predicted its ability to ameliorate ITP. We suggest that inhibition of in vitro platelet phagocytosis may prove to be a valuable tool for determining which erythrocyte antibodies would likely be candidates for clinical use in ITP.

Brachyury - a gene affecting mouse gastrulation and early organogenesis

Development ◽  
1992 ◽  
Vol 116 (Supplement) ◽  
pp. 157-165 ◽  
Author(s):  
R. S. P. Beddington ◽  
P. Rashbass ◽  
V. Wilson
Keyword(s):  
Es Cells ◽  
Embryonic Stem ◽  
Primitive Streak ◽  
Coat Colour ◽  
Es Cell ◽  
Wild Type ◽  
Mesoderm Cell ◽  
Rostrocaudal Axis

Mouse embryos that are homozygous for the Brachyury (T) deletion die at mid-gestation. They have prominent defects in the notochord, the allantois and the primitive streak. Expression of the T gene commences at the onset of gastrulation and is restricted to the primitive streak, mesoderm emerging from the streak, the head process and the notochord. Genetic evidence has suggested that there may be an increasing demand for T gene function along the rostrocaudal axis. Experiments reported here indicate that this may not be the case. Instead, the gradient in severity of the T defect may be caused by defective mesoderm cell movements, which result in a progressive accumulation of mesoderm cells near the primitive streak. Embryonic stem (ES) cells which are homozygous for the T deletion have been isolated and their differentiation in vitro and in vivo compared with that of heterozygous and wild-type ES cell lines. In +/+ ↔ T/T ES cell chimeras the Brachyury phenotype is not rescued by the presence of wild-type cells and high level chimeras show most of the features characteristic of intact T/T mutants. A few offspring from blastocysts injected with T/T ES cells have been born, several of which had greatly reduced or abnormal tails. However, little or no ES cell contribution was detectable in these animals, either as coat colour pigmentation or by isozyme analysis. Inspection of potential +/+ ↔ T/T ES cell chimeras on the 11th or 12th day of gestation, stages later than that at which intact T/T mutants die, revealed the presence of chimeras with caudal defects. These chimeras displayed a gradient of ES cell colonisation along the rostrocaudal axis with increased colonisation of caudal regions. In addition, the extent of chimerism in ectodermal tissues (which do not invaginate during gastrulation) tended to be higher than that in mesodermal tissues (which are derived from cells invaginating through the primitive streak). These results suggest that nascent mesoderm cells lacking the T gene are compromised in their ability to move away from the primitive streak. This indicates that one function of the T genemay be to regulate cell adhesion or cell motility properties in mesoderm cells. Wild-type cells in +/+ ↔ T/T chimeras appear to move normally to populate trunk and head mesoderm, suggesting that the reduced motility in T/T cells is a cell autonomous defect

Clock gene-independent daily regulation of haemoglobin oxidation in red blood cells

2021 ◽  
Author(s):  
Andrew D. Beale ◽  
Priya Crosby ◽  
Utham K. Valekunja ◽  
Rachel S. Edgar ◽  
Johanna E. Chesham ◽  
...  
Keyword(s):  
Circadian Rhythms ◽  
Red Blood Cells ◽  
Blood Cells ◽  
Human Subjects ◽  
Developmental Regulation ◽  
Physiological Role ◽  
Cell Types ◽  
The Body

AbstractCellular circadian rhythms confer daily temporal organisation upon behaviour and physiology that is fundamental to human health and disease. Rhythms are present in red blood cells (RBCs), the most abundant cell type in the body. Being naturally anucleate, RBC circadian rhythms share key elements of post-translational, but not transcriptional, regulation with other cell types. The physiological function and developmental regulation of RBC circadian rhythms is poorly understood, however, partly due to the small number of appropriate techniques available. Here, we extend the RBC circadian toolkit with a novel biochemical assay for haemoglobin oxidation status, termed “Bloody Blotting”. Our approach relies on a redox-sensitive covalent haem-haemoglobin linkage that forms during cell lysis. Formation of this linkage exhibits daily rhythms in vitro, which are unaffected by mutations that affect the timing of circadian rhythms in nucleated cells. In vivo, haemoglobin oxidation rhythms demonstrate daily variation in the oxygen-carrying and nitrite reductase capacity of the blood, and are seen in human subjects under controlled laboratory conditions as well as in freely-behaving humans. These results extend our molecular understanding of RBC circadian rhythms and suggest they serve an important physiological role in gas transport.

Vitamin D as Radiosensitizer: A Review in Cell Line -

2020 ◽  
Vol 10 (6) ◽  
pp. 315-324
Author(s):  
Fahmi Radityamurti ◽  
Fauzan Herdian ◽  
Tiara Bunga Mayang Permata ◽  
Handoko Handoko ◽  
Henry Kodrat ◽  
...  
Keyword(s):  
Vitamin D ◽  
Cell Differentiation ◽  
Cell Line ◽  
Cell Lines ◽  
Anticancer Agent ◽  
Medical Literature ◽  
In Vitro Studies ◽  
Anti Cancer

Introduction: Vitamin D has been shown to have anti-cancer properties such as antioxidants, anti-proliferative, and cell differentiation. The property of vitamin D as an anticancer agent triggers researchers to find out whether vitamin D is useful as a radiosensitizer. Multiple studies have been carried out on cell lines in various types of cancer, but the benefits of vitamin D as a radiosensitizer still controversial. This paperwork aims to investigate the utilization of Vitamin D3 (Calcitriol) as radiosensitizer in various cell line through literature review.Methods: A systematic search of available medical literature databases was performed on in-vitro studies with Vitamin D as a radiosensitizer in all types of cell lines. A total of 11 in-vitro studies were evaluated.Results: Nine studies in this review showed a significant effect of Vitamin D as a radiosensitizer agent by promoting cytotoxic autophagy, increasing apoptosis, inhibiting of cell survival and proliferation, promoting gene in ReIB inhibition, inducing senescene and necrosis. The two remaining studies showed no significant effect in the radiosensitizing mechanism of Vitamin D due to lack of evidence in-vitro settings.Conclusion: Vitamin D have anticancer property and can be used as a radiosensitizer by imploring various mechanism pathways in various cell lines. Further research especially in-vivo settings need to be evaluated.

Sex chiniaerism and germ cell distribution in a series of chimaeric mice

Development ◽  
1975 ◽  
Vol 33 (1) ◽  
pp. 205-216
Author(s):  
Anne McLaren
Keyword(s):  
Bone Marrow ◽  
Blood Cells ◽  
Chromosome Analysis ◽  
Chromosome Morphology ◽  
Mixed Population ◽  
Cell Distribution ◽  
Single Sex ◽  
Xx Males

1. Of 30 mice born from aggregation of embryos from a multiple recessive strain with F1 embryos carrying the contrasting alleles, 4 females and 20 males proved to be overtly chimaeric. 2. Three XX/XX females, five XY/XY males and eight XY/XX males were identified by chromosome analysis. Thus 50 % of the population analysed were sex chimaeras, and all of these developed as phenotypic males, though one showed evidence of hermaphroditism. 3. In seven XY/XX chimaeras that bred, the genetic component undergoing spermatogenesis coincided in every case with the component identified by chromosome morphology as XY. 4. The F1 component predominated in metaphase plates derived from cultured blood cells. Comparison with direct preparations from bone marrow suggested selection in favour of F1 cells, either through differential proliferation of stem cells in vivo or differential response to phytohaemagglutinin in vitro. 5. In XY/XX males, the percentage of XX cells detected varied from 1 % to 98 % in blood, and from 0 % to 80 % in bone marrow. 6. Of eight ‘single-sex’ chimaeras progeny-tested (three XX/XX, five XY/XY), only one showed evidence of a mixed population of germ cells. The proportion of the two types of progeny varied significantly from litter to litter, but was unrelated to the age of the male.

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