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Analysis of Vascular Morphogenesis in Zebrafish. Methods Mol Biol 2023; 2608:425-450. [PMID: 36653721 DOI: 10.1007/978-1-0716-2887-4_24] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
Analysis of cardiovascular development in zebrafish embryos has become a major driver of vascular research in recent years. Imaging-based analyses have allowed the discovery or verification of morphologically distinct processes and mechanisms of, e.g., endothelial cell migration, angiogenic sprouting, tip or stalk cell behavior, and vessel anastomosis. In this chapter, we describe the techniques and tools used for confocal imaging of zebrafish endothelial development in combination with general experimental approaches for molecular dissection of involved signaling pathways.
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2
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Haertter D, Wang X, Fogerson SM, Ramkumar N, Crawford JM, Poss KD, Di Talia S, Kiehart DP, Schmidt CF. DeepProjection: specific and robust projection of curved 2D tissue sheets from 3D microscopy using deep learning. Development 2022; 149:dev200621. [PMID: 36178108 PMCID: PMC9686994 DOI: 10.1242/dev.200621] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2022] [Accepted: 09/12/2022] [Indexed: 01/05/2023]
Abstract
The efficient extraction of image data from curved tissue sheets embedded in volumetric imaging data remains a serious and unsolved problem in quantitative studies of embryogenesis. Here, we present DeepProjection (DP), a trainable projection algorithm based on deep learning. This algorithm is trained on user-generated training data to locally classify 3D stack content, and to rapidly and robustly predict binary masks containing the target content, e.g. tissue boundaries, while masking highly fluorescent out-of-plane artifacts. A projection of the masked 3D stack then yields background-free 2D images with undistorted fluorescence intensity values. The binary masks can further be applied to other fluorescent channels or to extract local tissue curvature. DP is designed as a first processing step than can be followed, for example, by segmentation to track cell fate. We apply DP to follow the dynamic movements of 2D-tissue sheets during dorsal closure in Drosophila embryos and of the periderm layer in the elongating Danio embryo. DeepProjection is available as a fully documented Python package.
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Affiliation(s)
- Daniel Haertter
- Department of Physics and Soft Matter Center, Duke University, Durham, NC 27708, USA
- Institute of Pharmacology and Toxicology, Göttingen University Medical Center, Göttingen 37075, Germany
| | - Xiaolei Wang
- Advanced Light Imaging and Spectroscopy Facility, Department of Physics, Duke University, Durham, NC 27708, USA
| | | | - Nitya Ramkumar
- Department of Cell Biology, Duke University Medical Center, Durham, NC 27710, USA
| | | | - Kenneth D. Poss
- Department of Biology, Duke University, Durham, NC 27708, USA
- Department of Cell Biology, Duke University Medical Center, Durham, NC 27710, USA
| | - Stefano Di Talia
- Department of Cell Biology, Duke University Medical Center, Durham, NC 27710, USA
| | - Daniel P. Kiehart
- Department of Biology, Duke University, Durham, NC 27708, USA
- Department of Cell Biology, Duke University Medical Center, Durham, NC 27710, USA
| | - Christoph F. Schmidt
- Department of Physics and Soft Matter Center, Duke University, Durham, NC 27708, USA
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3
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Barone V, Lyons DC. Live imaging of echinoderm embryos to illuminate evo-devo. Front Cell Dev Biol 2022; 10:1007775. [PMID: 36187474 PMCID: PMC9521734 DOI: 10.3389/fcell.2022.1007775] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2022] [Accepted: 08/24/2022] [Indexed: 11/16/2022] Open
Abstract
Echinoderm embryos have been model systems for cell and developmental biology for over 150 years, in good part because of their optical clarity. Discoveries that shaped our understanding of fertilization, cell division and cell differentiation were only possible because of the transparency of sea urchin eggs and embryos, which allowed direct observations of intracellular structures. More recently, live imaging of sea urchin embryos, coupled with fluorescence microscopy, has proven pivotal to uncovering mechanisms of epithelial to mesenchymal transition, cell migration and gastrulation. However, live imaging has mainly been performed on sea urchin embryos, while echinoderms include numerous experimentally tractable species that present interesting variation in key aspects of morphogenesis, including differences in embryo compaction and mechanisms of blastula formation. The study of such variation would allow us not only to understand how tissues are formed in echinoderms, but also to identify which changes in cell shape, cell-matrix and cell-cell contact formation are more likely to result in evolution of new embryonic shapes. Here we argue that adapting live imaging techniques to more echinoderm species will be fundamental to exploit such an evolutionary approach to the study of morphogenesis, as it will allow measuring differences in dynamic cellular behaviors - such as changes in cell shape and cell adhesion - between species. We briefly review existing methods for live imaging of echinoderm embryos and describe in detail how we adapted those methods to allow long-term live imaging of several species, namely the sea urchin Lytechinus pictus and the sea stars Patiria miniata and Patiriella regularis. We outline procedures to successfully label, mount and image early embryos for 10–16 h, from cleavage stages to early blastula. We show that data obtained with these methods allows 3D segmentation and tracking of individual cells over time, the first step to analyze how cell shape and cell contact differ among species. The methods presented here can be easily adopted by most cell and developmental biology laboratories and adapted to successfully image early embryos of additional species, therefore broadening our understanding of the evolution of morphogenesis.
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4
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Modeling Lung Carcinoids with Zebrafish Tumor Xenograft. Int J Mol Sci 2022; 23:ijms23158126. [PMID: 35897702 PMCID: PMC9330857 DOI: 10.3390/ijms23158126] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2022] [Revised: 07/19/2022] [Accepted: 07/20/2022] [Indexed: 02/01/2023] Open
Abstract
Lung carcinoids are neuroendocrine tumors that comprise well-differentiated typical (TCs) and atypical carcinoids (ACs). Preclinical models are indispensable for cancer drug screening since current therapies for advanced carcinoids are not curative. We aimed to develop a novel in vivo model of lung carcinoids based on the xenograft of lung TC (NCI-H835, UMC-11, and NCI-H727) and AC (NCI-H720) cell lines and patient-derived cell cultures in Tg(fli1a:EGFP)y1 zebrafish embryos. We exploited this platform to test the anti-tumor activity of sulfatinib. The tumorigenic potential of TC and AC implanted cells was evaluated by the quantification of tumor-induced angiogenesis and tumor cell migration as early as 24 h post-injection (hpi). The characterization of tumor-induced angiogenesis was performed in vivo and in real time, coupling the tumor xenograft with selective plane illumination microscopy on implanted zebrafish embryos. TC-implanted cells displayed a higher pro-angiogenic potential compared to AC cells, which inversely showed a relevant migratory behavior within 48 hpi. Sulfatinib inhibited tumor-induced angiogenesis, without affecting tumor cell spread in both TC and AC implanted embryos. In conclusion, zebrafish embryos implanted with TC and AC cells faithfully recapitulate the tumor behavior of human lung carcinoids and appear to be a promising platform for drug screening.
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Pereida-Jaramillo E, Gómez-González GB, Espino-Saldaña AE, Martínez-Torres A. Calcium Signaling in the Cerebellar Radial Glia and Its Association with Morphological Changes during Zebrafish Development. Int J Mol Sci 2021; 22:ijms222413509. [PMID: 34948305 PMCID: PMC8706707 DOI: 10.3390/ijms222413509] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2021] [Revised: 12/08/2021] [Accepted: 12/12/2021] [Indexed: 01/02/2023] Open
Abstract
Radial glial cells are a distinct non-neuronal cell type that, during development, span the entire width of the brain walls of the ventricular system. They play a central role in the origin and placement of neurons, since their processes form structural scaffolds that guide and facilitate neuronal migration. Furthermore, glutamatergic signaling in the radial glia of the adult cerebellum (i.e., Bergmann glia), is crucial for precise motor coordination. Radial glial cells exhibit spontaneous calcium activity and functional coupling spread calcium waves. However, the origin of calcium activity in relation to the ontogeny of cerebellar radial glia has not been widely explored, and many questions remain unanswered regarding the role of radial glia in brain development in health and disease. In this study we used a combination of whole mount immunofluorescence and calcium imaging in transgenic (gfap-GCaMP6s) zebrafish to determine how development of calcium activity is related to morphological changes of the cerebellum. We found that the morphological changes in cerebellar radial glia are quite dynamic; the cells are remarkably larger and more elaborate in their soma size, process length and numbers after 7 days post fertilization. Spontaneous calcium events were scarce during the first 3 days of development and calcium waves appeared on day 5, which is associated with the onset of more complex morphologies of radial glia. Blockage of gap junction coupling inhibited the propagation of calcium waves, but not basal local calcium activity. This work establishes crucial clues in radial glia organization, morphology and calcium signaling during development and provides insight into its role in complex behavioral paradigms.
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Yi W, Rücklin M, Poelmann RE, Aldridge DC, Richardson MK. Normal stages of embryonic development of a brood parasite, the rosy bitterling Rhodeus ocellatus (Teleostei: Cypriniformes). J Morphol 2021; 282:783-819. [PMID: 33583089 PMCID: PMC8252481 DOI: 10.1002/jmor.21335] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2020] [Revised: 02/10/2021] [Accepted: 02/10/2021] [Indexed: 12/14/2022]
Abstract
Bitterlings, a group of freshwater teleosts, provide a fascinating example among vertebrates of the evolution of brood parasitism. Their eggs are laid inside the gill chamber of their freshwater mussel hosts where they develop as brood parasites. Studies of the embryonic development of bitterlings are crucial in deciphering the evolution of their distinct early life-history. Here, we have studied 255 embryos and larvae of the rosy bitterling (Rhodeus ocellatus) using in vitro fertilization and X-ray microtomography (microCT). We describe 11 pre-hatching and 13 post-hatching developmental stages spanning the first 14 days of development, from fertilization to the free-swimming stage. In contrast to previous developmental studies of various bitterling species, the staging system we describe is character-based and therefore more compatible with the widely-used stages described for zebrafish. Our bitterling data provide new insights into to the polarity of the chorion, and into notochord vacuolization and yolk sac extension in relation to body straightening. This study represents the first application of microCT scanning to bitterling development and provides one of the most detailed systematic descriptions of development in any teleost. Our staging series will be an important tool for heterochrony analysis and other comparative studies of teleost development, and may provide insight into the co-evolution of brood parasitism.
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Affiliation(s)
- Wenjing Yi
- Institute of BiologyUniversity of Leiden, Sylvius LaboratoryLeidenthe Netherlands
- The Key Laboratory of Aquatic Biodiversity and Conservation, Institute of HydrobiologyChinese Academy of SciencesHubeiChina
| | - Martin Rücklin
- Vertebrate Evolution, Development and EcologyNaturalis Biodiversity CenterLeidenThe Netherlands
| | - Robert E. Poelmann
- Institute of BiologyUniversity of Leiden, Sylvius LaboratoryLeidenthe Netherlands
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Okada K, Takada S. The second pharyngeal pouch is generated by dynamic remodeling of endodermal epithelium in zebrafish. Development 2020; 147:dev194738. [PMID: 33158927 DOI: 10.1242/dev.194738] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2020] [Accepted: 10/28/2020] [Indexed: 11/20/2022]
Abstract
Pharyngeal arches (PAs) are segmented by endodermal outpocketings called pharyngeal pouches (PPs). Anterior and posterior PAs appear to be generated by different mechanisms, but it is unclear how the anterior and posterior PAs combine. Here, we addressed this issue with precise live imaging of PP development and cell tracing of pharyngeal endoderm in zebrafish embryos. We found that two endodermal bulges are initially generated in the future second PP (PP2) region, which separates anterior and posterior PAs. Subsequently, epithelial remodeling causes contact between these two bulges, resulting in the formation of mature PP2 with a bilayered morphology. The rostral and caudal bulges develop into the operculum and gill, respectively. Development of the caudal PP2 and more posterior PPs is affected by impaired retinoic acid signaling or pax1a/b dysfunction, suggesting that the rostral front of posterior PA development corresponds to the caudal PP2. Our study clarifies an aspect of PA development that is essential for generation of a seamless array of PAs in zebrafish.
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Affiliation(s)
- Kazunori Okada
- Exploratory Research Center on Life and Living Systems, National Institutes of Natural Sciences, 5-1 Higashiyama, Myodaijicho, Okazaki 444-8787, Japan
- National Institute for Basic Biology, National Institutes of Natural Sciences, 5-1 Higashiyama, Myodaiji-cho, Okazaki 444-8787, Japan
| | - Shinji Takada
- Exploratory Research Center on Life and Living Systems, National Institutes of Natural Sciences, 5-1 Higashiyama, Myodaijicho, Okazaki 444-8787, Japan
- National Institute for Basic Biology, National Institutes of Natural Sciences, 5-1 Higashiyama, Myodaiji-cho, Okazaki 444-8787, Japan
- Department for Basic Biology, SOKENDAI (The Graduate University for Advanced Studies), 5-1 Higashiyama, Myodaiji-cho, Okazaki 444-8787, Japan
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Pang M, Bai L, Zong W, Wang X, Bu Y, Xiong C, Zheng J, Li J, Gao W, Feng Z, Chen L, Zhang J, Cheng H, Zhu X, Xiong JW. Light-sheet fluorescence imaging charts the gastrula origin of vascular endothelial cells in early zebrafish embryos. Cell Discov 2020; 6:74. [PMID: 33133634 PMCID: PMC7588447 DOI: 10.1038/s41421-020-00204-7] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2019] [Accepted: 08/11/2020] [Indexed: 12/29/2022] Open
Abstract
It remains challenging to construct a complete cell lineage map of the origin of vascular endothelial cells in any vertebrate embryo. Here, we report the application of in toto light-sheet fluorescence imaging of embryos to trace the origin of vascular endothelial cells (ECs) at single-cell resolution in zebrafish. We first adapted a previously reported method to embryo mounting and light-sheet imaging, created an alignment, fusion, and extraction all-in-one software (AFEIO) for processing big data, and performed quantitative analysis of cell lineage relationships using commercially available Imaris software. Our data revealed that vascular ECs originated from broad regions of the gastrula along the dorsal–ventral and anterior–posterior axes, of which the dorsal–anterior cells contributed to cerebral ECs, the dorsal–lateral cells to anterior trunk ECs, and the ventral–lateral cells to posterior trunk and tail ECs. Therefore, this work, to our knowledge, charts the first comprehensive map of the gastrula origin of vascular ECs in zebrafish, and has potential applications for studying the origin of any embryonic organs in zebrafish and other model organisms.
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Affiliation(s)
- Meijun Pang
- Beijing Key Laboratory of Cardiometabolic Molecular Medicine, Institute of Molecular Medicine and State Key Laboratory of Natural and Biomimetic Drugs, Peking University, Beijing 100871, China
| | - Linlu Bai
- Beijing Key Laboratory of Cardiometabolic Molecular Medicine, Institute of Molecular Medicine and State Key Laboratory of Natural and Biomimetic Drugs, Peking University, Beijing 100871, China.,Academy for Advanced Interdisciplinary Studies, Peking University, Beijing 100871, China
| | - Weijian Zong
- Beijing Key Laboratory of Cardiometabolic Molecular Medicine, Institute of Molecular Medicine and State Key Laboratory of Natural and Biomimetic Drugs, Peking University, Beijing 100871, China
| | - Xu Wang
- Beijing Key Laboratory of Cardiometabolic Molecular Medicine, Institute of Molecular Medicine and State Key Laboratory of Natural and Biomimetic Drugs, Peking University, Beijing 100871, China
| | - Ye Bu
- Beijing Key Laboratory of Cardiometabolic Molecular Medicine, Institute of Molecular Medicine and State Key Laboratory of Natural and Biomimetic Drugs, Peking University, Beijing 100871, China
| | - Connie Xiong
- Beijing Key Laboratory of Cardiometabolic Molecular Medicine, Institute of Molecular Medicine and State Key Laboratory of Natural and Biomimetic Drugs, Peking University, Beijing 100871, China
| | - Jiyuan Zheng
- Beijing Key Laboratory of Cardiometabolic Molecular Medicine, Institute of Molecular Medicine and State Key Laboratory of Natural and Biomimetic Drugs, Peking University, Beijing 100871, China
| | - Jieyi Li
- Beijing Key Laboratory of Cardiometabolic Molecular Medicine, Institute of Molecular Medicine and State Key Laboratory of Natural and Biomimetic Drugs, Peking University, Beijing 100871, China
| | - Weizheng Gao
- School of Engineering, Peking University, Beijing 100871, China
| | - Zhiheng Feng
- School of Engineering, Peking University, Beijing 100871, China
| | - Liangyi Chen
- Beijing Key Laboratory of Cardiometabolic Molecular Medicine, Institute of Molecular Medicine and State Key Laboratory of Natural and Biomimetic Drugs, Peking University, Beijing 100871, China
| | - Jue Zhang
- School of Engineering, Peking University, Beijing 100871, China
| | - Heping Cheng
- Beijing Key Laboratory of Cardiometabolic Molecular Medicine, Institute of Molecular Medicine and State Key Laboratory of Natural and Biomimetic Drugs, Peking University, Beijing 100871, China
| | - Xiaojun Zhu
- Beijing Key Laboratory of Cardiometabolic Molecular Medicine, Institute of Molecular Medicine and State Key Laboratory of Natural and Biomimetic Drugs, Peking University, Beijing 100871, China
| | - Jing-Wei Xiong
- Beijing Key Laboratory of Cardiometabolic Molecular Medicine, Institute of Molecular Medicine and State Key Laboratory of Natural and Biomimetic Drugs, Peking University, Beijing 100871, China.,Academy for Advanced Interdisciplinary Studies, Peking University, Beijing 100871, China
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Babkiewicz E, Bazała M, Urban P, Maszczyk P, Markowska M, Gliwicz ZM. The effects of temperature on the proxies of visual detection of Danio rerio larvae: observations from the optic tectum. Biol Open 2020; 9:bio047779. [PMID: 32694151 PMCID: PMC7390641 DOI: 10.1242/bio.047779] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2019] [Accepted: 06/02/2020] [Indexed: 11/27/2022] Open
Abstract
Numerous studies have indicated that temperature improves the visual capabilities of different ectotherms, including a variety of fish species. However, none of these studies has directly tested whether elevated temperature extends the visual detection distance - the distance from which a visual stimulus is detected. To test this hypothesis, we investigated the effect of temperature on the visual detection distance of zebrafish (Danio rerio) larvae by measuring the largest distance from a moving target that induced a neural response in the optic tectum. We applied advanced methods of functional calcium imaging such as selective plane illumination microscopy in combination with a miniature OLED screen. The screen displayed an artificial, mobile prey, appearing in the visual field of the larvae. We performed experiments in three temperature treatments (18, 23 and 28°C) on transgenic fish expressing a fluorescent probe (GCaMP5G) that changes intensity in response to altered Ca2+ concentrations in the nerves in the optic tectum. Based on the obtained data, we also measured three additional parameters of the neural response in the optic tectum, each being a proxy of sensitivity to changes in the stimulus movement. We did not confirm our hypothesis, since the visual detection distance shortened as the temperature increased. Moreover, all of the three additional parameters indicated a negative effect of the temperature on the speed of the neural response to the stimuli. However, the obtained results could be explained not only by worse visual capabilities at the elevated temperature, but also by the differences in the visual field and in turn, the retinotopic location of the visual stimulus between the temperature treatments, since the stimulus in the experiments moved horizontally rather than forward and backward from the fish's eye.
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Affiliation(s)
- Ewa Babkiewicz
- Department of Hydrobiology, Faculty of Biology, University of Warsaw at Biological and Chemical Research Centre, Żwirki i Wigury 101, 02-089 Warsaw, Poland
| | - Michał Bazała
- Laboratory of Neurodegeneration, International Institute of Molecular and Cell Biology in Warsaw, Księcia Trojdena 4, 02-109 Warsaw, Poland
| | - Paulina Urban
- Laboratory of Functional and Structural Genomics, Centre of New Technologies, University of Warsaw, Banacha 2c, 02-097 Warsaw, Poland
- College of Inter-Faculty Individual Studies in Mathematics and Natural Sciences, University of Warsaw, Banacha 2c, 02-097 Warsaw, Poland
| | - Piotr Maszczyk
- Department of Hydrobiology, Faculty of Biology, University of Warsaw at Biological and Chemical Research Centre, Żwirki i Wigury 101, 02-089 Warsaw, Poland
| | - Magdalena Markowska
- Department of Animal Physiology, Faculty of Biology, University of Warsaw, Miecznikowa 1, 02-096 Warsaw, Poland
| | - Z Maciej Gliwicz
- Department of Hydrobiology, Faculty of Biology, University of Warsaw at Biological and Chemical Research Centre, Żwirki i Wigury 101, 02-089 Warsaw, Poland
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10
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Kleinhans DS, Lecaudey V. Standardized mounting method of (zebrafish) embryos using a 3D-printed stamp for high-content, semi-automated confocal imaging. BMC Biotechnol 2019; 19:68. [PMID: 31640669 PMCID: PMC6805687 DOI: 10.1186/s12896-019-0558-y] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2019] [Accepted: 09/04/2019] [Indexed: 01/24/2023] Open
Abstract
Background Developmental biology relies to a large extent on the observation and comparison of phenotypic traits through time using high resolution microscopes. In this context, transparent model organisms such as the zebrafish Danio rerio in which developing tissues and organs can be easily observed and imaged using fluorescent proteins have become very popular. One limiting factor however is the acquisition of a sufficient amount of data, in standardized and reproducible conditions, to allow robust quantitative analysis. One way to improve this is by developing mounting methods to increase the number of embryos that can be imaged simultaneously in near-to-identical orientation. Results Here we present an improved mounting method allowing semi-automated and high-content imaging of zebrafish embryos. It is based on a 3D-printed stamp which is used to create a 2D coordinate system of multiple μ-wells in an agarose cast. Each μ-well models a negative of the average zebrafish embryo morphology between 22 and 96 h-post-fertilization. Due to this standardized and reproducible arrangement, it is possible to define a custom well plate in the respective imaging software that allows for a semi-automated imaging process. Furthermore, the improvement in Z-orientation significantly reduces post-processing and improves comparability of volumetric data while reducing light exposure and thus photo-bleaching and photo-toxicity, and improving signal-to-noise ratio (SNR). Conclusions We present here a new method that allows to standardize and improve mounting and imaging of embryos. The 3D-printed stamp creates a 2D coordinate system of μ-wells in an agarose cast thus standardizing specimen mounting and allowing high-content imaging of up to 44 live or mounted zebrafish embryos simultaneously in a semi-automated, well-plate like manner on inverted confocal microscopes. In summary, image data quality and acquisition efficiency (amount of data per time) are significantly improved. The latter might also be crucial when using the services of a microscopy facility.
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Affiliation(s)
- David Simon Kleinhans
- Department of Developmental Biology of Vertebrates, Institute for Cell biology and Neuroscience, Goethe University, Max-von-Laue-Str. 13, 60438, Frankfurt am Main, Germany
| | - Virginie Lecaudey
- Department of Developmental Biology of Vertebrates, Institute for Cell biology and Neuroscience, Goethe University, Max-von-Laue-Str. 13, 60438, Frankfurt am Main, Germany.
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11
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Laroche T, Burri O, Dubey LK, Seitz A. Development of Sample-Adaptable Holders for Lightsheet Microscopy. Front Neuroanat 2019; 13:26. [PMID: 30906253 PMCID: PMC6419145 DOI: 10.3389/fnana.2019.00026] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2018] [Accepted: 02/14/2019] [Indexed: 12/29/2022] Open
Abstract
Multi-user core microscopy facilities are often faced with the challenge to adapt or modify existing instruments. This is essential in order to fulfill the requirements of the user community, who wants to image a wide range of model organisms with varying stains and sample thicknesses. In recent years, lightsheet microscopy has turned into an invaluable tool for both live and cleared sample imaging of many different specimens. This brought up new challenges in terms of sample mounting as the classical approach of attachment onto a coverslip cannot be universally applied. Here we describe the development of a diversified holder which extends the range of samples which can be imaged on a Zeiss Lightsheet microscope Z1. We focus on mounting strategies of cleared specimens; however, the holder and mounting strategy can be applied to live specimens too. The proposed methodology provides very high flexibility along with numerous possibilities for adaptation based on imaging specimen size, condition and available clearing reagents. Moreover, the described mounting strategies can be applied to other light sheet microscopes that can mount 1 mL syringes.
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Affiliation(s)
- Thierry Laroche
- Bioimaging and Optics Platform, Faculty of Life Sciences, Ecole Polytechnique Fédérale de Lausanne, Lausanne, Switzerland
| | - Olivier Burri
- Bioimaging and Optics Platform, Faculty of Life Sciences, Ecole Polytechnique Fédérale de Lausanne, Lausanne, Switzerland
| | - Lalit Kumar Dubey
- Faculty of Biology and Medicine, Department of Biochemistry, University of Lausanne, Lausanne, Switzerland
| | - Arne Seitz
- Bioimaging and Optics Platform, Faculty of Life Sciences, Ecole Polytechnique Fédérale de Lausanne, Lausanne, Switzerland
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12
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Yang Z, Cole KLH, Qiu Y, Somorjai IML, Wijesinghe P, Nylk J, Cochran S, Spalding GC, Lyons DA, Dholakia K. Light sheet microscopy with acoustic sample confinement. Nat Commun 2019; 10:669. [PMID: 30737391 PMCID: PMC6368588 DOI: 10.1038/s41467-019-08514-5] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2018] [Accepted: 01/08/2019] [Indexed: 11/13/2022] Open
Abstract
Contactless sample confinement would enable a whole host of new studies in developmental biology and neuroscience, in particular, when combined with long-term, wide-field optical imaging. To achieve this goal, we demonstrate a contactless acoustic gradient force trap for sample confinement in light sheet microscopy. Our approach allows the integration of real-time environmentally controlled experiments with wide-field low photo-toxic imaging, which we demonstrate on a variety of marine animal embryos and larvae. To illustrate the key advantages of our approach, we provide quantitative data for the dynamic response of the heartbeat of zebrafish larvae to verapamil and norepinephrine, which are known to affect cardiovascular function. Optical flow analysis allows us to explore the cardiac cycle of the zebrafish and determine the changes in contractile volume within the heart. Overcoming the restrictions of sample immobilisation and mounting can open up a broad range of studies, with real-time drug-based assays and biomechanical analyses.
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Affiliation(s)
- Zhengyi Yang
- SUPA, School of Physics and Astronomy, University of St Andrews, St Andrews, KY16 9SS, UK.
- Electron Bio-Imaging Centre, Diamond Light Source, Harwell Science and Innovation Campus, Didcot, OX11 0DE, UK.
| | - Katy L H Cole
- Centre for Discovery Brain Sciences, MS Society Centre for Translational Research, Euan MacDonald Centre for Motor Neurone Disease Research, University of Edinburgh, Edinburgh, EH16 4SB, UK
| | - Yongqiang Qiu
- School of Engineering, University of Glasgow, Glasgow, G12 8QQ, UK
- Faculty of Engineering and Technology, Liverpool John Moores University, Liverpool, L3 3AF, UK
| | - Ildikó M L Somorjai
- The Scottish Oceans Institute, University of St Andrews, St Andrews, KY16 8LB, UK
- Biomedical Sciences Research Complex, North Haugh, University of St Andrews, St Andrews, KY16 9ST, UK
| | - Philip Wijesinghe
- SUPA, School of Physics and Astronomy, University of St Andrews, St Andrews, KY16 9SS, UK
- BRITElab, Harry Perkins Institute of Medical Research, QEII Medical Centre, Nedlands and Centre for Medical Research, The University of Western Australia, Perth, WA, 6009, Australia
- Department of Electrical, Electronic & Computer Engineering, School of Engineering, The University of Western Australia, Perth, WA, 6009, Australia
| | - Jonathan Nylk
- SUPA, School of Physics and Astronomy, University of St Andrews, St Andrews, KY16 9SS, UK
| | - Sandy Cochran
- School of Engineering, University of Glasgow, Glasgow, G12 8QQ, UK
| | - Gabriel C Spalding
- Department of Physics, Illinois Wesleyan University, Bloomington, IL, 61701, USA
| | - David A Lyons
- Centre for Discovery Brain Sciences, MS Society Centre for Translational Research, Euan MacDonald Centre for Motor Neurone Disease Research, University of Edinburgh, Edinburgh, EH16 4SB, UK
| | - Kishan Dholakia
- SUPA, School of Physics and Astronomy, University of St Andrews, St Andrews, KY16 9SS, UK.
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13
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Liu Y, Dale S, Ball R, VanLeuven AJ, Sornborger A, Lauderdale JD, Kner P. Imaging neural events in zebrafish larvae with linear structured illumination light sheet fluorescence microscopy. NEUROPHOTONICS 2019; 6:015009. [PMID: 30854407 PMCID: PMC6400141 DOI: 10.1117/1.nph.6.1.015009] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/24/2018] [Accepted: 02/13/2019] [Indexed: 05/02/2023]
Abstract
Light sheet fluorescence microscopy (LSFM) is a powerful tool for investigating model organisms including zebrafish. However, due to scattering and refractive index variations within the sample, the resulting image often suffers from low contrast. Structured illumination (SI) has been combined with scanned LSFM to remove out-of-focus and scattered light using square-law detection. Here, we demonstrate that the combination of LSFM with linear reconstruction SI can further increase resolution and contrast in the vertical and axial directions compared to the widely adopted root-mean square reconstruction method while using the same input images. We apply this approach to imaging neural activity in 7-day postfertilization zebrafish larvae. We imaged two-dimensional sections of the zebrafish central nervous system in two colors at an effective frame rate of 7 frames per second.
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Affiliation(s)
- Yang Liu
- University of Georgia, College of Engineering, Athens, Georgia, United States
| | - Savannah Dale
- Clemson University, Department of Bioengineering, Clemson, South Carolina, United States
| | - Rebecca Ball
- University of Georgia, Department of Cellular Biology, Athens, Georgia, United States
| | - Ariel J. VanLeuven
- University of Georgia, Department of Cellular Biology, Athens, Georgia, United States
| | - Andrew Sornborger
- Los Alamos National Laboratory, Information Sciences, CCS-3, Los Alamos, New Mexico, United States
| | - James D. Lauderdale
- University of Georgia, Department of Cellular Biology, Athens, Georgia, United States
- University of Georgia, Neuroscience Division of the Biomedical Health Sciences Institute, Athens, Georgia, United States
| | - Peter Kner
- University of Georgia, College of Engineering, Athens, Georgia, United States
- Address all correspondence to Peter Kner, E-mail:
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14
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Akle V, Agudelo-Dueñas N, Molina-Rodriguez MA, Kartchner LB, Ruth AM, González JM, Forero-Shelton M. Establishment of Larval Zebrafish as an Animal Model to Investigate Trypanosoma cruzi Motility In Vivo. J Vis Exp 2017. [PMID: 28994774 PMCID: PMC5752350 DOI: 10.3791/56238] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023] Open
Abstract
Chagas disease is a parasitic infection caused by Trypanosoma cruzi, whose motility is not only important for localization, but also for cellular binding and invasion. Current animal models for the study of T. cruzi allow limited observation of parasites in vivo, representing a challenge for understanding parasite behavior during the initial stages of infection in humans. This protozoan has a flagellar stage in both vector and mammalian hosts, but there are no studies describing its motility in vivo.The objective of this project was to establish a live vertebrate zebrafish model to evaluate T. cruzi motility in the vascular system. Transparent zebrafish larvae were injected with fluorescently labeled trypomastigotes and observed using light sheet fluorescence microscopy (LSFM), a noninvasive method to visualize live organisms with high optical resolution. The parasites could be visualized for extended periods of time due to this technique's relatively low risk of photodamage compared to confocal or epifluorescence microscopy. T. cruzi parasites were observed traveling in the circulatory system of live zebrafish in different-sized blood vessels and the yolk. They could also be seen attached to the yolk sac wall and to the atrioventricular valve despite the strong forces associated with heart contractions. LSFM of T. cruzi-inoculated zebrafish larvae is a valuable method that can be used to visualize circulating parasites and evaluate their tropism, migration patterns, and motility in the dynamic environment of the cardiovascular system of a live animal.
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Affiliation(s)
- Veronica Akle
- Laboratory of Neurosciences and Circadian Rhythms, School of Medicine, Universidad de los Andes;
| | - Nathalie Agudelo-Dueñas
- Laboratory of Neurosciences and Circadian Rhythms, School of Medicine, Universidad de los Andes; Biophysics Group, Department of Physics, Universidad de los Andes
| | | | - Laurel Brianne Kartchner
- Laboratory of Neurosciences and Circadian Rhythms, School of Medicine, Universidad de los Andes; Laboratory of Basic Medical Sciences, School of Medicine, Universidad de los Andes; Department of Microbiology and Immunology, University of North Carolina; USAID Research and Innovation Fellowship program
| | - Annette Marie Ruth
- Laboratory of Neurosciences and Circadian Rhythms, School of Medicine, Universidad de los Andes; Laboratory of Basic Medical Sciences, School of Medicine, Universidad de los Andes; Notre Dame Initiative for Global Development, University of Notre Dame; USAID Research and Innovation Fellowship program
| | - John M González
- Laboratory of Basic Medical Sciences, School of Medicine, Universidad de los Andes
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Richter V, Bruns S, Bruns T, Weber P, Wagner M, Cremer C, Schneckenburger H. Axial tomography in live cell laser microscopy. JOURNAL OF BIOMEDICAL OPTICS 2017; 22:91505. [PMID: 28122077 DOI: 10.1117/1.jbo.22.9.091505] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/11/2016] [Accepted: 01/03/2017] [Indexed: 06/06/2023]
Abstract
Single cell microscopy in a three-dimensional (3-D) environment is reported. Cells are grown in an agarose culture gel, located within microcapillaries and observed from different sides after adaptation of an innovative device for sample rotation. Thus, z -stacks can be recorded by confocal microscopy in different directions and used for illustration in 3-D. This gives additional information, since cells or organelles that appear superimposed in one direction, may be well resolved in another one. The method is tested and validated with single cells expressing a membrane or a mitochondrially associated green fluorescent protein, or cells accumulating fluorescent quantum dots. In addition, axial tomography supports measurements of cellular uptake and distribution of the anticancer drug doxorubicin in the nucleus (2 to 6 h after incubation) or the cytoplasm (24 h). This paper discusses that upon cell rotation an enhanced optical resolution in lateral direction compared to axial direction can be utilized to obtain an improved effective 3-D resolution, which represents an important step toward super-resolution microscopy of living cells.
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Affiliation(s)
- Verena Richter
- Aalen University, Institute of Applied Research, Beethovenstraße 1, 73430 Aalen, Germany
| | - Sarah Bruns
- Aalen University, Institute of Applied Research, Beethovenstraße 1, 73430 Aalen, Germany
| | - Thomas Bruns
- Aalen University, Institute of Applied Research, Beethovenstraße 1, 73430 Aalen, Germany
| | - Petra Weber
- Aalen University, Institute of Applied Research, Beethovenstraße 1, 73430 Aalen, Germany
| | - Michael Wagner
- Aalen University, Institute of Applied Research, Beethovenstraße 1, 73430 Aalen, Germany
| | - Christoph Cremer
- University of Heidelberg, Institute of Pharmacy and Molecular Biology, Im Neuenheimer Feld 364, 69120 Heidelberg, GermanycInstitute of Molecular Biology, Ackermannweg 4, 55128 Mainz, Germany
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16
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Abstract
Myelination by oligodendrocytes in the central nervous system (CNS) and Schwann cells in the peripheral nervous system is essential for nervous system function and health. Despite its importance, we have a relatively poor understanding of the molecular and cellular mechanisms that regulate myelination in the living animal, particularly in the CNS. This is partly due to the fact that myelination commences around birth in mammals, by which time the CNS is complex and largely inaccessible, and thus very difficult to image live in its intact form. As a consequence, in recent years much effort has been invested in the use of smaller, simpler, transparent model organisms to investigate mechanisms of myelination in vivo. Although the majority of such studies have employed zebrafish, the Xenopus tadpole also represents an important complementary system with advantages for investigating myelin biology in vivo. Here we review how the natural features of zebrafish embryos and larvae and Xenopus tadpoles make them ideal systems for experimentally interrogating myelination by live imaging. We outline common transgenic technologies used to generate zebrafish and Xenopus that express fluorescent reporters, which can be used to image myelination. We also provide an extensive overview of the imaging modalities most commonly employed to date to image the nervous system in these transparent systems, and also emerging technologies that we anticipate will become widely used in studies of zebrafish and Xenopus myelination in the near future.
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Affiliation(s)
- Jenea M Bin
- Centre for Neuroregeneration, MS Society Centre for Translational Research, Euan MacDonald Centre for Motor Neurone Disease Research, University of Edinburgh, Edinburgh, UK
| | - David A Lyons
- Centre for Neuroregeneration, MS Society Centre for Translational Research, Euan MacDonald Centre for Motor Neurone Disease Research, University of Edinburgh, Edinburgh, UK
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17
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Icha J, Schmied C, Sidhaye J, Tomancak P, Preibisch S, Norden C. Using Light Sheet Fluorescence Microscopy to Image Zebrafish Eye Development. J Vis Exp 2016:e53966. [PMID: 27167079 PMCID: PMC4941907 DOI: 10.3791/53966] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023] Open
Abstract
Light sheet fluorescence microscopy (LSFM) is gaining more and more popularity as a method to image embryonic development. The main advantages of LSFM compared to confocal systems are its low phototoxicity, gentle mounting strategies, fast acquisition with high signal to noise ratio and the possibility of imaging samples from various angles (views) for long periods of time. Imaging from multiple views unleashes the full potential of LSFM, but at the same time it can create terabyte-sized datasets. Processing such datasets is the biggest challenge of using LSFM. In this protocol we outline some solutions to this problem. Until recently, LSFM was mostly performed in laboratories that had the expertise to build and operate their own light sheet microscopes. However, in the last three years several commercial implementations of LSFM became available, which are multipurpose and easy to use for any developmental biologist. This article is primarily directed to those researchers, who are not LSFM technology developers, but want to employ LSFM as a tool to answer specific developmental biology questions. Here, we use imaging of zebrafish eye development as an example to introduce the reader to LSFM technology and we demonstrate applications of LSFM across multiple spatial and temporal scales. This article describes a complete experimental protocol starting with the mounting of zebrafish embryos for LSFM. We then outline the options for imaging using the commercially available light sheet microscope. Importantly, we also explain a pipeline for subsequent registration and fusion of multiview datasets using an open source solution implemented as a Fiji plugin. While this protocol focuses on imaging the developing zebrafish eye and processing data from a particular imaging setup, most of the insights and troubleshooting suggestions presented here are of general use and the protocol can be adapted to a variety of light sheet microscopy experiments.
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Affiliation(s)
- Jaroslav Icha
- Max Planck Institute of Molecular Cell Biology and Genetics;
| | | | | | - Pavel Tomancak
- Max Planck Institute of Molecular Cell Biology and Genetics
| | - Stephan Preibisch
- Max Planck Institute of Molecular Cell Biology and Genetics; HHMI Janelia Research Campus; Berlin Institute of Medical Systems Biology of the Max Delbrück Center
| | - Caren Norden
- Max Planck Institute of Molecular Cell Biology and Genetics;
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18
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Imaging fluorescence (cross-) correlation spectroscopy in live cells and organisms. Nat Protoc 2015; 10:1948-74. [DOI: 10.1038/nprot.2015.100] [Citation(s) in RCA: 127] [Impact Index Per Article: 14.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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Abstract
Long-term fluorescence live-cell imaging experiments have long been limited by the effects of excitation-induced phototoxicity. The advent of light-sheet microscopy now allows users to overcome this limitation by restricting excitation to a narrow illumination plane. In addition, light-sheet imaging allows for high-speed image acquisition with uniform illumination of samples composed of multiple cell layers. The majority of studies conducted thus far have used custom-built platforms with specialized hardware and software, along with specific sample handling approaches. The first versatile commercially available light-sheet microscope, Lightsheet Z.1, offers a number of innovative solutions, but it requires specific strategies for sample handling during long-term imaging experiments. There are currently no standard procedures describing the preparation of plant specimens for imaging with the Lightsheet Z.1. Here we describe a detailed protocol to prepare plant specimens for light-sheet microscopy, in which Arabidopsis seeds or seedlings are placed in solid medium within glass capillaries or fluorinated ethylene propylene tubes. Preparation of plant material for imaging may be completed within one working day.
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20
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Lenard A, Daetwyler S, Betz C, Ellertsdottir E, Belting HG, Huisken J, Affolter M. Endothelial cell self-fusion during vascular pruning. PLoS Biol 2015; 13:e1002126. [PMID: 25884426 PMCID: PMC4401649 DOI: 10.1371/journal.pbio.1002126] [Citation(s) in RCA: 106] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2014] [Accepted: 03/10/2015] [Indexed: 12/30/2022] Open
Abstract
During embryonic development, vascular networks remodel to meet the increasing demand of growing tissues for oxygen and nutrients. This is achieved by the pruning of redundant blood vessel segments, which then allows more efficient blood flow patterns. Because of the lack of an in vivo system suitable for high-resolution live imaging, the dynamics of the pruning process have not been described in detail. Here, we present the subintestinal vein (SIV) plexus of the zebrafish embryo as a novel model to study pruning at the cellular level. We show that blood vessel regression is a coordinated process of cell rearrangements involving lumen collapse and cell-cell contact resolution. Interestingly, the cellular rearrangements during pruning resemble endothelial cell behavior during vessel fusion in a reversed order. In pruning segments, endothelial cells first migrate toward opposing sides where they join the parental vascular branches, thus remodeling the multicellular segment into a unicellular connection. Often, the lumen is maintained throughout this process, and transient unicellular tubes form through cell self-fusion. In a second step, the unicellular connection is resolved unilaterally, and the pruning cell rejoins the opposing branch. Thus, we show for the first time that various cellular activities are coordinated to achieve blood vessel pruning and define two different morphogenetic pathways, which are selected by the flow environment.
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Affiliation(s)
- Anna Lenard
- Biozentrum der Universität Basel, Basel, Switzerland
| | - Stephan Daetwyler
- Max Planck Institute of Molecular Cell Biology and Genetics, Dresden, Germany
| | - Charles Betz
- Biozentrum der Universität Basel, Basel, Switzerland
| | | | | | - Jan Huisken
- Max Planck Institute of Molecular Cell Biology and Genetics, Dresden, Germany
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21
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Bruneel B, Mathä M, Paesen R, Ameloot M, Weninger WJ, Huysseune A. Imaging the zebrafish dentition: from traditional approaches to emerging technologies. Zebrafish 2015; 12:1-10. [PMID: 25560992 PMCID: PMC4298156 DOI: 10.1089/zeb.2014.0980] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
The zebrafish, a model organism for which a plethora of molecular and genetic techniques exists, has a lifelong replacing dentition of 22 pharyngeal teeth. This is in contrast to the mouse, which is the key organism in dental research but whose teeth are never replaced. Employing the zebrafish as the main organism to elucidate the mechanisms of continuous tooth replacement, however, poses at least one major problem, related to the fact that all teeth are located deep inside the body. Investigating tooth replacement thus relies on conventional histological methods, which are often laborious, time-consuming and can cause tissue deformations. In this review, we investigate the advantages and limitations of adapting current visualization techniques to dental research in zebrafish. We discuss techniques for fast sectioning, such as vibratome sectioning and high-resolution episcopic microscopy, and methods for in toto visualization, such as Alizarin red staining, micro-computed tomography, and optical projection tomography. Techniques for in vivo imaging, such as two-photon excitation fluorescence and second harmonic generation microscopy, are also covered. Finally, the possibilities of light sheet microscopy are addressed.
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Affiliation(s)
- Bart Bruneel
- Evolutionary Developmental Biology, Ghent University, Ghent, Belgium
| | - Markus Mathä
- IMG Centre for Anatomy and Cell Biology, Medical University of Vienna, Vienna, Austria
| | - Rik Paesen
- BIOMED, University Hasselt and Transnational University Limburg, Diepenbeek, Belgium
| | - Marcel Ameloot
- BIOMED, University Hasselt and Transnational University Limburg, Diepenbeek, Belgium
| | - Wolfgang J. Weninger
- IMG Centre for Anatomy and Cell Biology, Medical University of Vienna, Vienna, Austria
| | - Ann Huysseune
- Evolutionary Developmental Biology, Ghent University, Ghent, Belgium
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