1
|
Abay A, Simionato G, Chachanidze R, Bogdanova A, Hertz L, Bianchi P, van den Akker E, von Lindern M, Leonetti M, Minetti G, Wagner C, Kaestner L. Glutaraldehyde - A Subtle Tool in the Investigation of Healthy and Pathologic Red Blood Cells. Front Physiol 2019; 10:514. [PMID: 31139090 PMCID: PMC6527840 DOI: 10.3389/fphys.2019.00514] [Citation(s) in RCA: 35] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2019] [Accepted: 04/11/2019] [Indexed: 01/03/2023] Open
Abstract
Glutaraldehyde is a well-known substance used in biomedical research to fix cells. Since hemolytic anemias are often associated with red blood cell shape changes deviating from the biconcave disk shape, conservation of these shapes for imaging in general and 3D-imaging in particular, like confocal microscopy, scanning electron microscopy or scanning probe microscopy is a common desire. Along with the fixation comes an increase in the stiffness of the cells. In the context of red blood cells this increased rigidity is often used to mimic malaria infected red blood cells because they are also stiffer than healthy red blood cells. However, the use of glutaraldehyde is associated with numerous pitfalls: (i) while the increase in rigidity by an application of increasing concentrations of glutaraldehyde is an analog process, the fixation is a rather digital event (all or none); (ii) addition of glutaraldehyde massively changes osmolality in a concentration dependent manner and hence cell shapes can be distorted; (iii) glutaraldehyde batches differ in their properties especially in the ratio of monomers and polymers; (iv) handling pitfalls, like inducing shear artifacts of red blood cell shapes or cell density changes that needs to be considered, e.g., when working with cells in flow; (v) staining glutaraldehyde treated red blood cells need different approaches compared to living cells, for instance, because glutaraldehyde itself induces a strong fluorescence. Within this paper we provide documentation about the subtle use of glutaraldehyde on healthy and pathologic red blood cells and how to deal with or circumvent pitfalls.
Collapse
Affiliation(s)
- Asena Abay
- Dynamics of Fluids, Department of Experimental Physics, Saarland University, Saarbrücken, Germany.,Landsteiner Laboratory, Sanquin, Amsterdam, Netherlands
| | - Greta Simionato
- Dynamics of Fluids, Department of Experimental Physics, Saarland University, Saarbrücken, Germany.,Theoretical Medicine and Biosciences, Saarland University, Homburg, Germany
| | - Revaz Chachanidze
- Dynamics of Fluids, Department of Experimental Physics, Saarland University, Saarbrücken, Germany.,Université Grenoble Alpes, CNRS, Grenoble INP, LRP, Grenoble, France
| | - Anna Bogdanova
- Red Blood Cell Research Group, Institute of Veterinary Physiology, Vetsuisse Faculty and the Zurich Center for Integrative Human Physiology (ZIHP), University of Zurich, Zurich, Switzerland
| | - Laura Hertz
- Dynamics of Fluids, Department of Experimental Physics, Saarland University, Saarbrücken, Germany.,Theoretical Medicine and Biosciences, Saarland University, Homburg, Germany
| | - Paola Bianchi
- UOC Ematologia, UOS Fisiopatologia delle Anemie, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Milan, Italy
| | | | | | - Marc Leonetti
- Université Grenoble Alpes, CNRS, Grenoble INP, LRP, Grenoble, France
| | - Giampaolo Minetti
- Laboratory of Biochemistry, Department of Biology and Biotechnology, University of Pavia, Pavia, Italy
| | - Christian Wagner
- Dynamics of Fluids, Department of Experimental Physics, Saarland University, Saarbrücken, Germany.,Physics and Materials Science Research Unit, University of Luxembourg, Luxembourg City, Luxembourg
| | - Lars Kaestner
- Dynamics of Fluids, Department of Experimental Physics, Saarland University, Saarbrücken, Germany.,Theoretical Medicine and Biosciences, Saarland University, Homburg, Germany
| |
Collapse
|
2
|
Chan EH, Chavadimane Shivakumar P, Clément R, Laugier E, Lenne PF. Patterned cortical tension mediated by N-cadherin controls cell geometric order in the Drosophila eye. eLife 2017; 6. [PMID: 28537220 PMCID: PMC5443664 DOI: 10.7554/elife.22796] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2016] [Accepted: 05/08/2017] [Indexed: 12/22/2022] Open
Abstract
Adhesion molecules hold cells together but also couple cell membranes to a contractile actomyosin network, which limits the expansion of cell contacts. Despite their fundamental role in tissue morphogenesis and tissue homeostasis, how adhesion molecules control cell shapes and cell patterns in tissues remains unclear. Here we address this question in vivo using the Drosophila eye. We show that cone cell shapes depend little on adhesion bonds and mostly on contractile forces. However, N-cadherin has an indirect control on cell shape. At homotypic contacts, junctional N-cadherin bonds downregulate Myosin-II contractility. At heterotypic contacts with E-cadherin, unbound N-cadherin induces an asymmetric accumulation of Myosin-II, which leads to a highly contractile cell interface. Such differential regulation of contractility is essential for morphogenesis as loss of N-cadherin disrupts cell rearrangements. Our results establish a quantitative link between adhesion and contractility and reveal an unprecedented role of N-cadherin on cell shapes and cell arrangements. DOI:http://dx.doi.org/10.7554/eLife.22796.001
Collapse
|