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Philosophical Transactions of the Royal... Dec 2022In amniotic vertebrates (birds, reptiles and mammals), an extraembryonic structure called the chorioallantoic membrane (CAM) functions as respiratory organ for embryonic...
In amniotic vertebrates (birds, reptiles and mammals), an extraembryonic structure called the chorioallantoic membrane (CAM) functions as respiratory organ for embryonic development. The CAM is derived from fusion between two pre-existing membranes, the allantois, a hindgut diverticulum and a reservoir for metabolic waste, and the chorion which marks the embryo's external boundary. Modified CAM in eutherian mammals, including humans, gives rise to chorioallantoic placenta. Despite its importance, little is known about cellular and molecular mechanisms mediating CAM formation and maturation. In this work, using the avian model, we focused on the early phase of CAM morphogenesis when the allantois and chorion meet and initiate fusion. We report here that chicken chorioallantoic fusion takes place when the allantois reaches the size of 2.5-3.0 mm in diameter and in about 6 hours between E3.75 and E4. Electron microscopy and immunofluorescence analyses suggested that before fusion, in both the allantois and chorion, an epithelial-shaped mesothelial layer is present, which dissolves after fusion, presumably by undergoing epithelial-mesenchymal transition. The fusion process , however, is independent of allantoic growth, circulation, or its connection to the developing mesonephros. Mesoderm cells derived from the allantois and chorion can intermingle post-fusion, and chorionic ectoderm cells exhibit a specialized sub-apical intercellular interface, possibly to facilitate infiltration of allantois-derived vascular progenitors into the chorionic ectoderm territory for optimal oxygen transport. Finally, we investigated chorioallantoic fusion-like process in primates, with limited numbers of archived human and fresh macaque samples. We summarize the similarities and differences of CAM formation among different amniote groups and propose that mesothelial epithelial-mesenchymal transition mediates chorioallantoic fusion in most amniotic vertebrates. Further study is needed to clarify tissue morphogenesis leading to chorioallantoic fusion in primates. Elucidating molecular mechanisms regulating mesothelial integrity and epithelial-mesenchymal transition will also help understand mesothelial diseases in the adult, including mesothelioma, ovarian cancer and fibrosis. This article is part of the theme issue 'Extraembryonic tissues: exploring concepts, definitions and functions across the animal kingdom'.
Topics: Allantois; Animals; Chorioallantoic Membrane; Chorion; Epithelium; Humans; Mammals; Oxygen
PubMed: 36252211
DOI: 10.1098/rstb.2021.0263 -
Angiogenesis Oct 2014The chicken chorioallantoic membrane (CAM) is a simple, highly vascularized extraembryonic membrane, which performs multiple functions during embryonic development,... (Review)
Review
The chicken chorioallantoic membrane (CAM) is a simple, highly vascularized extraembryonic membrane, which performs multiple functions during embryonic development, including but not restricted to gas exchange. Over the last two decades, interest in the CAM as a robust experimental platform to study blood vessels has been shared by specialists working in bioengineering, development, morphology, biochemistry, transplant biology, cancer research and drug development. The tissue composition and accessibility of the CAM for experimental manipulation, makes it an attractive preclinical in vivo model for drug screening and/or for studies of vascular growth. In this article we provide a detailed review of the use of the CAM to study vascular biology and response of blood vessels to a variety of agonists. We also present distinct cultivation protocols discussing their advantages and limitations and provide a summarized update on the use of the CAM in vascular imaging, drug delivery, pharmacokinetics and toxicology.
Topics: Animals; Bioengineering; Biomedical Research; Blood Vessels; Cell Line, Tumor; Chickens; Chorioallantoic Membrane; Drug Delivery Systems; Humans; Models, Animal; Models, Biological; Neovascularization, Physiologic
PubMed: 25138280
DOI: 10.1007/s10456-014-9440-7 -
Cancer Treatment and Research... 2021Osteosarcoma is extremely malignant, and the most common cancer that affects bone. Current treatments involve surgical resection of the affected area and multi-agent... (Review)
Review
Osteosarcoma is extremely malignant, and the most common cancer that affects bone. Current treatments involve surgical resection of the affected area and multi-agent chemotherapy, though survival rate is generally poor for those affected by metastases. As treatment for osteosarcoma has remained unchanged for the past few decades, there is a need for further advancements in the understanding of osteosarcoma biology and therapeutics. Thus, reliable animal models that can accurately recapitulate the disease are required. Though rodents represent the most popular animal model of osteosarcoma, they may not model the disease best. This review analyzes emerging alternative non-rodent animal models of osteosarcoma, such as the chick chorioallantoic membrane (CAM) assay, pigs, and canines. Each of these alternatives offer advantages over classic rodent models for pre-clinical research. Research of these cross-species platforms imparts knowledge of metastases biology and potential new treatments for osteosarcoma.
Topics: Animals; Animals, Genetically Modified; Bone Neoplasms; Cell Line, Tumor; Chickens; Chorioallantoic Membrane; Disease Models, Animal; Dogs; Osteosarcoma; Swine; Xenograft Model Antitumor Assays
PubMed: 33453605
DOI: 10.1016/j.ctarc.2021.100307 -
Mechanisms of Development Aug 2016During avian development the mesodermal layers of the allantois and chorion fuse to form the chorioallantoic membrane (CAM). This structure rapidly expands generating a... (Review)
Review
During avian development the mesodermal layers of the allantois and chorion fuse to form the chorioallantoic membrane (CAM). This structure rapidly expands generating a rich vascular network that provides an interface for gas and waste exchange. The CAM allows to study tissue grafts, tumor growth and metastasis, wound healing, drugs delivery and toxicologic analysis, and angiogenic and anti-angiogenic molecules. The CAM is relatively simple, quick, and low-cost model that allows screening of a large number of pharmacological samples in a short time; does not require administrative procedures for obtaining ethics committee approval for animal experimentation. Moreover, being naturally immunodeficient, the chick embryo may receive transplantations from different tissues and species, without immune responses.
Topics: Allantois; Animals; Chick Embryo; Chorioallantoic Membrane; Chorion; Embryonic Development; Endothelium, Vascular; Humans; Models, Animal; Neoplasms; Neovascularization, Physiologic
PubMed: 27178379
DOI: 10.1016/j.mod.2016.05.003 -
Cells, Tissues, Organs 2022A variety of in vivo experimental models have been established for the studies of human cancer using both cancer cell lines and patient-derived xenografts (PDXs). In... (Review)
Review
A variety of in vivo experimental models have been established for the studies of human cancer using both cancer cell lines and patient-derived xenografts (PDXs). In order to meet the aspiration of precision medicine, the in vivomurine models have been widely adopted. However, common constraints such as high cost, long duration of experiments, and low engraftment efficiency remained to be resolved. The chick embryo chorioallantoic membrane (CAM) is an alternative model to overcome some of these limitations. Here, we provide an overview of the applications of the chick CAM model in the study of oncology. The CAM model has shown significant retention of tumor heterogeneity alongside increased xenograft take rates in several PDX studies. Various imaging techniques and data analysis have been applied to study tumor metastasis, angiogenesis, and therapeutic response to novel agents. Lastly, to practically illustrate the feasibility of utilizing the CAM model, we summarize the general protocol used in a case study utilizing an ovarian cancer PDX.
Topics: Animals; Chick Embryo; Chorioallantoic Membrane; Disease Models, Animal; Heterografts; Humans; Neoplasms; Neovascularization, Pathologic
PubMed: 33780951
DOI: 10.1159/000513039 -
Cells Feb 2023With a history of more than 100 years of different applications in various scientific fields, the chicken chorioallantoic membrane (CAM) assay has proven itself to be an... (Review)
Review
With a history of more than 100 years of different applications in various scientific fields, the chicken chorioallantoic membrane (CAM) assay has proven itself to be an exceptional scientific model that meets the requirements of the replacement, reduction, and refinement principle (3R principle). As one of three extraembryonic avian membranes, the CAM is responsible for fetal respiration, metabolism, and protection. The model provides a unique constellation of immunological, vascular, and extracellular properties while being affordable and reliable at the same time. It can be utilized for research purposes in cancer biology, angiogenesis, virology, and toxicology and has recently been used for biochemistry, pharmaceutical research, and stem cell biology. Stem cells and, in particular, mesenchymal stem cells derived from adipose tissue (ADSCs) are emerging subjects for novel therapeutic strategies in the fields of tissue regeneration and personalized medicine. Because of their easy accessibility, differentiation profile, immunomodulatory properties, and cytokine repertoire, ADSCs have already been established for different preclinical applications in the files mentioned above. In this review, we aim to highlight and identify some of the cross-sections for the potential utilization of the CAM model for ADSC studies with a focus on wound healing and tissue engineering, as well as oncological research, e.g., sarcomas. Hereby, the focus lies on the combination of existing evidence and experience of such intersections with a potential utilization of the CAM model for further research on ADSCs.
Topics: Animals; Stem Cell Research; Chorioallantoic Membrane; Tissue Engineering; Adipose Tissue
PubMed: 36831259
DOI: 10.3390/cells12040592 -
Journal of Visualized Experiments : JoVE Jan 2020Mouse models are the benchmark tests for in vivo cancer studies. However, cost, time, and ethical considerations have led to calls for alternative in vivo cancer models....
Mouse models are the benchmark tests for in vivo cancer studies. However, cost, time, and ethical considerations have led to calls for alternative in vivo cancer models. The chicken chorioallantoic membrane (CAM) model provides an inexpensive, rapid alternative that permits direct visualization of tumor development and is suitable for in vivo imaging. As such, we sought to develop an optimized protocol for engrafting gynecological and urological tumors into this model, which we present here. Approximately 7 days postfertilization, the air cell is moved to the vascularized side of the egg, where an opening is created in the shell. Tumors from murine and human cell lines and primary tissues can then be engrafted. These are typically seeded in a mixture of extracellular matrix and medium to avoid cellular dispersal and provide nutrient support until the cells recruit a vascular supply. Tumors may then grow for up to an additional 14 days prior to the eggs hatching. By implanting cells stably transduced with firefly luciferase, bioluminescence imaging can be used for the sensitive detection of tumor growth on the membrane and cancer cell spread throughout the embryo. This model can potentially be used to study tumorigenicity, invasion, metastasis, and therapeutic effectiveness. The chicken CAM model requires significantly less time and financial resources compared to traditional murine models. Because the eggs are immunocompromised and immune tolerant, tissues from any organism can potentially be implanted without costly transgenic animals (e.g., mice) required for implantation of human tissues. However, many of the advantages of this model could potentially also be limitations, including the short tumor generation time and immunocompromised/immune tolerant status. Additionally, although all tumor types presented here engraft in the chicken chorioallantoic membrane model, they do so with varying degrees of tumor growth.
Topics: Animals; Chickens; Chorioallantoic Membrane; Disease Models, Animal; Female; Genital Neoplasms, Female; Humans; Urologic Neoplasms
PubMed: 32065133
DOI: 10.3791/60651 -
Poultry Science Mar 2021In all vertebrates, hypoxia plays an important role in fetal development, driving vasculogenesis, angiogenesis, hematopoiesis, and chondrogenesis. Therefore, the ability... (Review)
Review
In all vertebrates, hypoxia plays an important role in fetal development, driving vasculogenesis, angiogenesis, hematopoiesis, and chondrogenesis. Therefore, the ability to sense and respond to changes in the availability of oxygen (O) is crucial for normal embryonic development as well as for developmental plasticity. Moderate levels of hypoxia trigger a regulated process which leads to adaptive responses. Regulation of angiogenesis by hypoxia is an important component of homeostatic control mechanisms that link the cardio-pulmonary-vascular O supply to metabolic demands in local tissues. Hypoxia leads to the activation of genes that are important for cell and tissue adaptation to low O conditions, such as hypoxia-inducible factor 1. Previous studies have shown a dose-response effect to hypoxia in chicken embryos, with lower and/or prolonged O levels affecting multiple mechanisms and providing a spectrum of responses that facilitate the ability to maintain O demand despite environmental hypoxia. In chicken embryos, mild to extreme hypoxia during embryogenesis improves chorioallantoic membrane and cardiovascular development, resulting in an increase in O carrying capacity and leading to developmental plasticity that may affect post-hatch chick performance and improve adaptation to additional environmental stresses at suboptimal environmental conditions.
Topics: Animals; Chick Embryo; Chickens; Chorioallantoic Membrane; Embryonic Development; Hypoxia; Oxygen
PubMed: 33652530
DOI: 10.1016/j.psj.2020.12.048 -
Technology in Cancer Research &... 2023Conforming to the current replace-reduce-refine 3Rs' guidelines in animal experiments, a series of explorative efforts have been made to set up operable biomedical... (Review)
Review
Conforming to the current replace-reduce-refine 3Rs' guidelines in animal experiments, a series of explorative efforts have been made to set up operable biomedical imaging-guided platforms for qualitative and quantitative evaluations on pharmacological effects of tumor vascular-disrupting agents (VDAs), based on the chick embryos (CEs) with its chorioallantoic membrane (CAM), in this overview. The techniques and platforms have been hierarchically elaborated, from macroscopic to microscopic and from overall to specific aspects. A protocol of LED lamplight associated with a new deep-learning algorithm was consolidated to screen out weak CEs by using the CAM vasculature imaging. 3D magnetic resonance imaging (MRI) and laser speckle contrast imaging (LSCI) to monitor the evolution of CE and vascular changes in CAM are introduced. A LSCI-CAM platform for studying the effects of VDAs on normal and cancerous vasculature of CAM and possible molecular mechanisms has been demonstrated. Finally, practical challenges and future perspectives are highlighted. The aim of this article is to help peers in biomedical research to familiarize with the CAM platform and to optimize imaging protocols for the evaluation of vasoactive pharmaceuticals, especially anticancer vascular targeted therapy.
Topics: Animals; Chick Embryo; Chorioallantoic Membrane; Magnetic Resonance Imaging; Pharmaceutical Preparations
PubMed: 37844882
DOI: 10.1177/15330338231206985 -
Poultry Science Feb 2022During chicken embryonic development, skeleton calcification mainly relies on the eggshell, whose minerals are progressively solubilized and transported to the embryo...
During chicken embryonic development, skeleton calcification mainly relies on the eggshell, whose minerals are progressively solubilized and transported to the embryo via the chorioallantoic membrane (CAM). However, the molecular components involved in this process remain undefined. We assessed eggshell demineralization and calcification of the embryo skeleton after 12 and 16 d of incubation, and analyzed the expression of several candidate genes in the CAM: carbonic anhydrases that are likely involved in secretion of protons for eggshell dissolution (CA2, CA4, CA9), ions transporters and regulators (CALB1, SLC4A1, ATP6V1B2, SGK1, SCGN, PKD2) and vitamin-D binding protein (GC). Our results confirmed that eggshell weight, thickness, and strength decreased during incubation, with a concomitant increase in calcification of embryonic skeletal system. In the CAM, the expression of CA2 increased during incubation while CA4 and CA9 were expressed at similar levels at both stages. SCL4A1 and SCGN were expressed, but not differentially, between the two stages, while the expression of ATP6V1B2 and PKD2 genes decreased. The expression of SGK1 and TRPV6 increased over time, although the expression of the latter gene was barely detectable. In parallel, we analyzed the expression of these candidate genes in the yolk sac (YS), which mediates the transfer of yolk minerals to the embryo during the first half of incubation. In YS, CA2 expression increases during incubation, similar to the CAM, while the expression of the other candidate genes decreases. Moreover, CALB1 and GC genes were found to be expressed during incubation in the YS, in contrast to the CAM where no expression of either was detected. This study demonstrates that the regulation of genes involved in the mobilization of egg minerals during embryonic development is different between the YS and CAM extraembryonic structures. Identification of the full suite of molecular components involved in the transfer of eggshell calcium to the embryo via the CAM should help to better understand the role of this structure in bone mineralization.
Topics: Animals; Chick Embryo; Chickens; Chorioallantoic Membrane; Egg Shell; Embryonic Development; Ovum; Yolk Sac
PubMed: 34959155
DOI: 10.1016/j.psj.2021.101622