Transepithelial calcium transport in the chick chorioallantoic membrane. I. Isolation and characterization of chorionic ectoderm cells

1993 ◽  
Vol 105 (2) ◽  
pp. 369-379 ◽  
Author(s):  
R.E. Akins ◽  
R.S. Tuan
Keyword(s):  
Calcium Binding ◽  
Chorioallantoic Membrane ◽  
Experimental Manipulation ◽  
Transepithelial Transport ◽  
Temperature Sensitive ◽  
Specific Cell ◽  
Chick Chorioallantoic Membrane ◽  
Isolation And Characterization

The chicken eggshell supplies approximately 80% of the calcium found in the hatchling chick. The mobilization of eggshell calcium into the developing embryo involves the transepithelial transport of large amounts of calcium in a development-specific manner. The cells responsible for the transport of eggshell calcium into the embryonic circulation are the ectodermal cells of the chorioallantoic membrane. In this report, we present a method for the isolation and culture of chorioallantoic membrane ectodermal cells, which are amenable to direct experimental manipulation. Cell preparations are characterized with respect to the expression of an ectoderm-specific cell surface marker (transcalcin, a calcium-binding protein), and a specific enzymatic activity (elevated Ca(2+)-activated ATPase). Functional assessment of in vitro cellular calcium uptake by 45Ca2+ tracer kinetics indicates the persistence of a temperature-sensitive, rapid-influx pathway similar to that observed in vivo. The preparations of primary ectodermal cells present an in vitro system applicable to the experimental analysis of calcium metabolism and transport by the chick chorioallantoic membrane.

scholarly journals Isolation and characterization of an inhibitor of neovascularization from scapular chondrocytes.

1992 ◽  
Vol 119 (2) ◽  
pp. 475-482 ◽  
Author(s):  
M A Moses ◽  
J Sudhalter ◽  
R Langer
Keyword(s):  
Growth Factor ◽  
Potent Inhibitor ◽  
Chorioallantoic Membrane ◽  
Boyden Chamber ◽  
Chick Chorioallantoic Membrane ◽  
Isolation And Characterization ◽  
Apparent Homogeneity ◽  
Sds Page ◽  
And Migration

An inhibitor of neovascularization from the conditioned media of scapular chondrocytes established and maintained in serum-free culture has been isolated and characterized. To determine whether this chondrocyte-derived inhibitor (ChDI) was capable of inhibiting neovascularization in vivo, this protein was assayed in the chick chorioallantoic membrane assay. ChDI was a potent inhibitor of angiogenesis in vivo (4 micrograms = 87% avascular zones). This inhibitor is also an inhibitor of fibroblast growth factor-stimulated capillary endothelial cell (EC) proliferation and migration, as well as being an inhibitor of mammalian collagenase. ChDI significantly suppressed capillary EC proliferation in a dose-dependent, reversible manner with an IC50 (the inhibitory concentration at which 50% inhibition is achieved) of 2.025 micrograms/ml. Inhibition by ChDI of growth factor-stimulated capillary EC migration was also observed using a modified Boyden chamber assay (IC50 = 255 ng/ml). SDS-PAGE analysis followed by silver staining of ChDI purified to apparent homogeneity revealed a single band having an M(r) of 35,550. Gel elution experiments demonstrated that only protein eluting at this molecular weight was anti-angiogenic. These studies are the first demonstration that chondrocytes in culture can produce a highly enriched, potent inhibitor of neovascularization which also inhibits collagenase.

scholarly journals A novel method of screening combinations of angiostatics identifies bevacizumab and temsirolimus as synergistic inhibitors of glioma-induced angiogenesis

PLoS ONE ◽  
2021 ◽  
Vol 16 (6) ◽  
pp. e0252233
Author(s):  
Michael I. Dorrell ◽  
Heidi R. Kast-Woelbern ◽  
Ryan T. Botts ◽  
Stephen A. Bravo ◽  
Jacob R. Tremblay ◽  
...  
Keyword(s):  
Side Effects ◽  
Tumor Angiogenesis ◽  
Clinical Success ◽  
Low Cost ◽  
Chorioallantoic Membrane ◽  
Cellular Interactions ◽  
Compensatory Mechanisms ◽  
Chick Chorioallantoic Membrane

Tumor angiogenesis is critical for the growth and progression of cancer. As such, angiostasis is a treatment modality for cancer with potential utility for multiple types of cancer and fewer side effects. However, clinical success of angiostatic monotherapies has been moderate, at best, causing angiostatic treatments to lose their early luster. Previous studies demonstrated compensatory mechanisms that drive tumor vascularization despite the use of angiostatic monotherapies, as well as the potential for combination angiostatic therapies to overcome these compensatory mechanisms. We screened clinically approved angiostatics to identify specific combinations that confer potent inhibition of tumor-induced angiogenesis. We used a novel modification of the ex ovo chick chorioallantoic membrane (CAM) model that combined confocal and automated analyses to quantify tumor angiogenesis induced by glioblastoma tumor onplants. This model is advantageous due to its low cost and moderate throughput capabilities, while maintaining complex in vivo cellular interactions that are difficult to replicate in vitro. After screening multiple combinations, we determined that glioblastoma-induced angiogenesis was significantly reduced using a combination of bevacizumab (Avastin®) and temsirolimus (Torisel®) at doses below those where neither monotherapy demonstrated activity. These preliminary results were verified extensively, with this combination therapy effective even at concentrations further reduced 10-fold with a CI value of 2.42E-5, demonstrating high levels of synergy. Thus, combining bevacizumab and temsirolimus has great potential to increase the efficacy of angiostatic therapy and lower required dosing for improved clinical success and reduced side effects in glioblastoma patients.

scholarly journals Angiogenic property of silk fibroin scaffolds with adipose-derived stem cells on chick chorioallantoic membrane

2021 ◽  
Vol 8 (3) ◽  
Author(s):  
Tanapong Watchararot ◽  
Weerapong Prasongchean ◽  
Peerapat Thongnuek
Keyword(s):  
Stem Cells ◽  
Silk Fibroin ◽  
Pore Diameter ◽  
Chorioallantoic Membrane ◽  
Control Group ◽  
Adipose Derived Stem Cells ◽  
Chick Chorioallantoic Membrane ◽  
Human Adipose Stem Cells

Angiogenesis is a crucial step in tissue regeneration and repair. Biomaterials that allow or promote angiogenesis are thus beneficial. In this study, angiogenic properties of salt-leached silk fibroin (SF) scaffolds seeded with human adipose stem cells (hADSCs) were studied using chick chorioallantoic membrane (CAM) as a model. The hADSC-seeded SF scaffolds (SF-hADSC) with the porosity of 77.34 ± 6.96% and the pore diameter of 513.95 ± 4.99 µm were implanted on the CAM of chick embryos that were on an embryonic day 8 (E8) of development. The SF-hADSC scaffolds induced a spoke-wheel pattern of capillary network indicative of angiogenesis, which was evident since E11. Moreover, the ingrowth of blood vessels into the scaffolds was seen in histological sections. The unseeded scaffolds induced the same extent of angiogenesis later on E14. By contrast, the control group could not induce the same extent of angiogenesis. In vitro cytotoxicity tests and in vivo angioirritative study reaffirmed the biocompatibility of the scaffolds. This work highlighted that the biocompatible SF-hADSC scaffolds accelerate angiogenesis, and hence they can be a promising biomaterial for the regeneration of tissues that require angiogenesis.

scholarly journals In vivo paracrine interaction between urokinase and its receptor: effect on tumor cell invasion.

1991 ◽  
Vol 115 (4) ◽  
pp. 1107-1112 ◽  
Author(s):  
L Ossowski ◽  
G Clunie ◽  
M T Masucci ◽  
F Blasi
Keyword(s):  
Chorioallantoic Membrane ◽  
Fold Increase ◽  
Cell Types ◽  
Cell Surface Receptor ◽  
In Vivo Model ◽  
Specific Cell ◽  
Upa Receptor ◽  
Surface Receptor

Numerous studies have linked the production of increased levels of urokinase type plasminogen activator (uPA) with the malignant phenotype. It has also been shown that a specific cell surface receptor can bind uPA through a domain distinct and distant from the proteolytic domain. In an in vivo model of invasion, consisting of experimentally modified chorioallantoic membrane (CAM) of a chick embryo, only cells that concurrently expressed both uPA and a receptor for uPA, and in which the receptor was saturated with uPA, were efficient in invasion. To test whether uPA produced by one cell can, in a paracrine fashion, affect the invasive capacity of a receptor-expressing cell, we transfected LB6 mouse cells with human uPA (LB6[uPA]), or human uPA-receptor cDNA (LB6[uPAR]). LB6(uPA) cells released into the medium 1-2 Ploug units of human uPA per 10(6) cells in 24 h. The LB6(uPAR) cells expressed on their surface approximately 12,000 high affinity (Kd 1.7 x 10(-10) M uPA binding sites per cell. Unlabeled LB6(uPA) and 125-IUdR-labeled LB6(uPAR) cells were coinoculated onto experimentally wounded and resealed CAMs and their invasion was compared to that of homologous mixtures of labeled and unlabeled LB6(uPAR) or LB6(uPA) cells. Concurrent presence of both cell types in the CAMs resulted in a 1.8-fold increase of invasion of the uPA-receptor expressing cells. A four-fold stimulation of invasion was observed when cells were cocultured in vitro, prior to in vivo inoculation. Enhancement of invasion was prevented in both sets of experiments by treatment with specific antihuman uPA antibodies, indicating that uPA was the main mediator of the invasion-enhancing, paracrine effect on the receptor-expressing cells.

scholarly journals Biological Effect and Mechanism of the miR-23b-3p/ANXA2 Axis in Pancreatic Ductal Adenocarcinoma

2018 ◽  
Vol 50 (3) ◽  
pp. 823-840 ◽  
Author(s):  
Dan-ming Wei ◽  
Yi-wu Dang ◽  
Zhen-bo Feng ◽  
Lu Liang ◽  
Lu Zhang ◽  
...  
Keyword(s):  
Pancreatic Ductal Adenocarcinoma ◽  
Chorioallantoic Membrane ◽  
Tumor Formation ◽  
Ductal Adenocarcinoma ◽  
Luciferase Reporter ◽  
Migration And Invasion ◽  
Chick Chorioallantoic Membrane ◽  
Pancreatic Cancer Cells

Background/Aims: Accumulating evidence strongly suggests that microRNAs (miRNAs) modulate the expression of known tumor suppressor genes and oncogenes. In the present study, we found that the proliferation and invasion ability of pancreatic ductal adenocarcinoma (PDAC) cells were significantly suppressed by the overexpression of miR-23b-3p. In addition, there are miR-23b-3p binding sites in annexin A2 (ANXA2). Here, we investigated whether miR-23b-3p had an impact on the progression and metastasis of PDAC by targeting ANXA2. Methods: Cell proliferation, migration, and invasion, and cell cycle assays were performed to explore the effect of miR-23b-3p on various malignant phenotypes of pancreatic cancer cells. The size of tumors was observed following miR-23b-3p overexpression in an in vivo chick chorioallantoic membrane assay. Dual-luciferase reporter, quantitative real-time PCR, western blot, and immunohistochemical analyses were used to validate the relationship between miR-23b-3p and ANXA2 in vitro. Results: We observed that miR-23b-3p could bind specifically to the 3′ untranslated region of ANXA2 and inhibit its expression. MiR-23b-3p overexpression downregulated the expression of ANXA2 mRNA in PDAC cells and limited the size of tumors or even prevented tumor formation. In addition, there was a negative correlation between miR-23b-3p expression and ANXA2 protein expression in clinical specimens. Conclusion: MiR-23b-3p inhibits the development and progression of PDAC by regulating ANXA2 directly.

On the mechanism of thrombin-induced angiogenesis: involvement of αvβ3-integrin

2002 ◽  
Vol 283 (5) ◽  
pp. C1501-C1510 ◽  
Author(s):  
Nikos E. Tsopanoglou ◽  
Paraskevi Andriopoulou ◽  
Michael E. Maragoudakis
Keyword(s):  
Endothelial Cells ◽  
Vascular Tissue ◽  
Chorioallantoic Membrane ◽  
Membrane System ◽  
Angiogenic Factor ◽  
Αvβ3 Integrin ◽  
Cellular Effects ◽  
Chick Chorioallantoic Membrane

Thrombin has been reported to be a potent angiogenic factor both in vitro and in vivo, and many of the cellular effects of thrombin may contribute to activation of angiogenesis. In this report we show that thrombin-treatment of human endothelial cells increases mRNA and protein levels of αvβ3-integrin. This thrombin-mediated effect is specific, dose dependent, and requires the catalytic site of thrombin. In addition, thrombin interacts with αvβ3as demonstrated by direct binding of αvβ3protein to immobilized thrombin. This interaction of thrombin with αvβ3-integrin, which is an angiogenic marker in vascular tissue, is of functional significance. Immobilized thrombin promotes endothelial cells attachment, migration, and survival. Antibody to αvβ3or a specific peptide antagonist to αvβ3can abolish all these αvβ3-mediated effects. Furthermore, in the chick chorioallantoic membrane system, the antagonist peptide to αvβ3diminishes both basal and the thrombin-induced angiogenesis. These results support the pivotal role of thrombin in activation of endothelial cells and angiogenesis and may be related to the clinical observation of neovascularization within thrombi.

scholarly journals Calcium-binding protein of the chick chorioallantoic membrane. II. Vitamin K-dependent expression

1978 ◽  
Vol 77 (3) ◽  
pp. 752-761 ◽  
Author(s):  
RS Tuan ◽  
WA Scott ◽  
ZA Cohn
Keyword(s):  
Vitamin D ◽  
Vitamin K ◽  
Calcium Binding ◽  
Binding Protein ◽  
Vitamin K Antagonists ◽  
Chorioallantoic Membrane ◽  
Calcium Binding Protein ◽  
Simple Method ◽  
Chick Chorioallantoic Membrane

A simple method was devised for the maintenance of the chorioallantoic membrane (CAM) of chick embryos in organ culture. Explants of CAM survived for up to 5 days in this system and retained the characteristic three-layered morphology (ectoderm, mesoderm, and endoderm). Induction of the CAM calcium-binding protein (CaBP) by effectors of calcium metabolism was studied in these organ cultures. Vitamin K was found to elicit a seven- to eightfold increase in CaBP, whereas no increase in CaBP activity occurred on supplementation with vitamin A, parathyroid hormone, an analogue of vitamin D, vitamin D and its hydroxylated metabolites, or with elevated calcium levels. The vitamin K-mediated induction of CaBP was dose-dependent, inhibited by the vitamin K antagonists warfarin and dicoumarol, selective for vitamin K5, and maximal at the developmental stage (13-15 days of incubation) corresponding to the onset of calcium transport by the CAM in vivo. CaBP levels increased after 60-70 h in cultures of 13-15 day CAM supplemented with vitamin K and reached maximal levels around 80-90 h of culture. The CAM ectoderm underwent extensive proliferation and often assumed a villuslike morphology in the vitamin K cultures.

scholarly journals N6-Methyladenosine Methyltransferase METTL3 Promotes Angiogenesis and Atherosclerosis by Upregulating the JAK2/STAT3 Pathway via m6A Reader IGF2BP1

2021 ◽  
Vol 9 ◽  
Author(s):  
Guo Dong ◽  
Jiangbo Yu ◽  
Gaojun Shan ◽  
Lide Su ◽  
Nannan Yu ◽  
...  
Keyword(s):  
Molecular Mechanisms ◽  
Chorioallantoic Membrane ◽  
Tube Formation ◽  
Luciferase Reporter ◽  
Dependent Manner ◽  
Stat3 Pathway ◽  
Protein Levels ◽  
Chick Chorioallantoic Membrane

Atherosclerosis (AS) is a life-threatening vascular disease. RNA N6-methyladenosine (m6A) modification level is dysregulated in multiple pathophysiologic processes including AS. In this text, the roles and molecular mechanisms of m6A writer METTL3 in AS progression were explored in vitro and in vivo. In the present study, cell proliferative, migratory, and tube formation capacities were assessed through CCK-8, Transwell migration, and tube formation assays, respectively. RNA m6A level was examined through a commercial kit. RNA and protein levels of genes were measured through RT-qPCR and western blot assays, respectively. VEGF secretion level was tested through ELISA assay. JAK2 mRNA stability was detected through actinomycin D assay. The relationship of METTL3, IGF2BP1, and JAK2 was investigated through bioinformatics analysis, MeRIP, RIP, RNA pull-down, and luciferase reporter assays. An AS mouse model was established to examine the effect of METTL3 knockdown on AS development in vivo. The angiogenetic activity was examined through chick chorioallantoic membrane assay in vivo. The results showed that METTL3 was highly expressed in ox-LDL-induced dysregulated HUVECs. METTL3 knockdown inhibited cell proliferation, migration, tube formation, and VEGF expression/secretion in ox-LDL-treated HUVECs, hampered AS process in vivo, and prevented in vivo angiogenesis of developing embryos. METTL3 positively regulated JAK2 expression and JAK2/STAT3 pathway in an m6A dependent manner in HUVECs. IGF2BP1 positively regulated JAK2 expression through directly binding to an m6A site within JAK2 mRNA in HUVECs. METTL3 knockdown weakened the interaction of JAK2 and IGF2BP1. METTL3 exerted its functions through JAK2/STAT3 pathway. In conclusion, METTL3 knockdown prevented AS progression by inhibiting JAK2/STAT3 pathway via IGF2BP1.

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