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Hade AC, Philips MA, Promet L, Jagomäe T, Hanumantharaju A, Salumäe L, Reimann E, Plaas M, Vasar E, Väli M. A cost-effective and efficient ex vivo, ex situ human whole brain perfusion protocol for immunohistochemistry. J Neurosci Methods 2024; 404:110059. [PMID: 38218387 DOI: 10.1016/j.jneumeth.2024.110059] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2023] [Revised: 12/18/2023] [Accepted: 01/07/2024] [Indexed: 01/15/2024]
Abstract
BACKGROUND Chemical fixation of the brain can be executed through either the immersion method or the perfusion method. Perfusion fixation allows for better preservation of the brain tissue's ultrastructure, as it provides rapid and uniform delivery of the fixative to the tissue. Still, not all facilities have the expertise to perform perfusion fixation, with initial high cost and complexity of perfusion systems as the main factors limiting its widespread usage. NEW METHOD Here we present our low-cost approach of whole brain ex situ perfusion fixation to overcome the aforementioned limitations. Our self-made perfusion system, constructed utilising commercially accessible and affordable medical resources alongside laboratory and everyday items, demonstrates the capability to generate superior histological stainings of brain tissue. The perfused tissue can be stored prior to proceeding with IHC for at least one year. RESULTS Our method yielded high-quality results in histological stainings using both free-floating cryosections and paraffin-embedded tissue sections. The system is fully reusable and complies with the principles of sustainable management. COMPARISON WITH EXISTING METHODS Our whole brain perfusion system has been assembled from simple components and is able to achieve a linear flow with a pressure of 70 mmHg corresponding to the perfusion pressure of the brain. CONCLUSIONS Our ex situ method can be especially useful in research settings where expensive perfusion systems are not affordable or in any field with high time pressure, making it suitable for the field of forensic medicine or pathology in general.
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Affiliation(s)
- Andreas-Christian Hade
- Department of Pathological Anatomy and Forensic Medicine, University of Tartu, 19 Ravila Street, 50411 Tartu, Estonia; Estonian Forensic Science Institute, Tervise 20, Tallinn, Estonia
| | - Mari-Anne Philips
- Department of Physiology, Institute of Biomedicine and Translational Medicine, University of Tartu, Tartu, Estonia; Centre of Excellence in Genomics and Translational Medicine, University of Tartu, Tartu, Estonia.
| | - Liisi Promet
- International Max Planck Research School for Neurosciences, University of Göttingen, Göttingen, Germany
| | - Toomas Jagomäe
- Department of Physiology, Institute of Biomedicine and Translational Medicine, University of Tartu, Tartu, Estonia; Centre of Excellence in Genomics and Translational Medicine, University of Tartu, Tartu, Estonia
| | - Arpana Hanumantharaju
- Department of Physiology, Institute of Biomedicine and Translational Medicine, University of Tartu, Tartu, Estonia; Centre of Excellence in Genomics and Translational Medicine, University of Tartu, Tartu, Estonia
| | - Liis Salumäe
- Pathology Service, Tartu University Hospital; Tartu, Estonia
| | - Ene Reimann
- Estonian Genome Centre, Institute of Genomics, University of Tartu, Tartu, Estonia
| | - Mario Plaas
- Department of Physiology, Institute of Biomedicine and Translational Medicine, University of Tartu, Tartu, Estonia; Centre of Excellence in Genomics and Translational Medicine, University of Tartu, Tartu, Estonia
| | - Eero Vasar
- Department of Physiology, Institute of Biomedicine and Translational Medicine, University of Tartu, Tartu, Estonia; Centre of Excellence in Genomics and Translational Medicine, University of Tartu, Tartu, Estonia
| | - Marika Väli
- Department of Pathological Anatomy and Forensic Medicine, University of Tartu, 19 Ravila Street, 50411 Tartu, Estonia; Estonian Forensic Science Institute, Tervise 20, Tallinn, Estonia
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Habicher J, Sanvido I, Bühler A, Sartori S, Piccoli G, Carl M. The Risk Genes for Neuropsychiatric Disorders negr1 and opcml Are Expressed throughout Zebrafish Brain Development. Genes (Basel) 2024; 15:363. [PMID: 38540422 PMCID: PMC10969947 DOI: 10.3390/genes15030363] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2024] [Revised: 03/11/2024] [Accepted: 03/12/2024] [Indexed: 06/14/2024] Open
Abstract
The immunoglobulin LAMP/OBCAM/NTM (IgLON) family of cell adhesion molecules comprises five members known for their involvement in establishing neural circuit connectivity, fine-tuning, and maintenance. Mutations in IgLON genes result in alterations in these processes and can lead to neuropsychiatric disorders. The two IgLON family members NEGR1 and OPCML share common links with several of them, such as schizophrenia, autism, and major depressive disorder. However, the onset and the underlying molecular mechanisms have remained largely unresolved, hampering progress in developing therapies. NEGR1 and OPCML are evolutionarily conserved in teleosts like the zebrafish (Danio rerio), which is excellently suited for disease modelling and large-scale screening for disease-ameliorating compounds. To explore the potential applicability of zebrafish for extending our knowledge on NEGR1- and OPCML-linked disorders and to develop new therapeutic strategies, we investigated the spatio-temporal expression of the two genes during early stages of development. negr1 and opcml are expressed maternally and subsequently in partially distinct domains of conserved brain regions. Other areas of expression in zebrafish have not been reported in mammals to date. Our results indicate that NEGR1 and OPCML may play roles in neural circuit development and function at stages earlier than previously anticipated. A detailed functional analysis of the two genes based on our findings could contribute to understanding the mechanistic basis of related psychiatric disorders.
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Affiliation(s)
- Judith Habicher
- Department of Cellular, Computational and Integrative Biology, CIBIO, University of Trento, 38123 Trento, Italy; (J.H.); (I.S.); (A.B.); (S.S.); (G.P.)
| | - Ilaria Sanvido
- Department of Cellular, Computational and Integrative Biology, CIBIO, University of Trento, 38123 Trento, Italy; (J.H.); (I.S.); (A.B.); (S.S.); (G.P.)
| | - Anja Bühler
- Department of Cellular, Computational and Integrative Biology, CIBIO, University of Trento, 38123 Trento, Italy; (J.H.); (I.S.); (A.B.); (S.S.); (G.P.)
- Molecular Cardiology, Department of Internal Medicine II, University of Ulm, 89081 Ulm, Germany
| | - Samuele Sartori
- Department of Cellular, Computational and Integrative Biology, CIBIO, University of Trento, 38123 Trento, Italy; (J.H.); (I.S.); (A.B.); (S.S.); (G.P.)
| | - Giovanni Piccoli
- Department of Cellular, Computational and Integrative Biology, CIBIO, University of Trento, 38123 Trento, Italy; (J.H.); (I.S.); (A.B.); (S.S.); (G.P.)
| | - Matthias Carl
- Department of Cellular, Computational and Integrative Biology, CIBIO, University of Trento, 38123 Trento, Italy; (J.H.); (I.S.); (A.B.); (S.S.); (G.P.)
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Spatiotemporal expression of IgLON family members in the developing mouse nervous system. Sci Rep 2021; 11:19536. [PMID: 34599206 PMCID: PMC8486791 DOI: 10.1038/s41598-021-97768-5] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2021] [Accepted: 08/25/2021] [Indexed: 02/08/2023] Open
Abstract
Differential expression of cell adhesion molecules in neuronal populations is one of the many mechanisms promoting the formation of functional neural circuits in the developing nervous system. The IgLON family consists of five cell surface immunoglobulin proteins that have been associated with various developmental disorders, such as autism spectrum disorder, schizophrenia, and major depressive disorder. However, there is still limited and fragmented information about their patterns of expression in certain regions of the developing nervous system and how their expression contributes to their function. Utilizing an in situ hybridization approach, we have analyzed the spatiotemporal expression of all IgLON family members in the developing mouse brain, spinal cord, eye, olfactory epithelium, and vomeronasal organ. At one prenatal (E16) and two postnatal (P0 and P15) ages, we show that each IgLON displays distinct expression patterns in the olfactory system, cerebral cortex, midbrain, cerebellum, spinal cord, and eye, indicating that they likely contribute to the wiring of specific neuronal circuitry. These analyses will inform future functional studies aimed at identifying additional roles for these proteins in nervous system development.
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