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Lipp HP, Krackow S, Turkes E, Benner S, Endo T, Russig H. IntelliCage: the development and perspectives of a mouse- and user-friendly automated behavioral test system. Front Behav Neurosci 2024; 17:1270538. [PMID: 38235003 PMCID: PMC10793385 DOI: 10.3389/fnbeh.2023.1270538] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2023] [Accepted: 10/18/2023] [Indexed: 01/19/2024] Open
Abstract
IntelliCage for mice is a rodent home-cage equipped with four corner structures harboring symmetrical double panels for operant conditioning at each of the two sides, either by reward (access to water) or by aversion (non-painful stimuli: air-puffs, LED lights). Corner visits, nose-pokes and actual licks at bottle-nipples are recorded individually using subcutaneously implanted transponders for RFID identification of up to 16 adult mice housed in the same home-cage. This allows for recording individual in-cage activity of mice and applying reward/punishment operant conditioning schemes in corners using workflows designed on a versatile graphic user interface. IntelliCage development had four roots: (i) dissatisfaction with standard approaches for analyzing mouse behavior, including standardization and reproducibility issues, (ii) response to handling and housing animal welfare issues, (iii) the increasing number of mouse models had produced a high work burden on classic manual behavioral phenotyping of single mice. and (iv), studies of transponder-chipped mice in outdoor settings revealed clear genetic behavioral differences in mouse models corresponding to those observed by classic testing in the laboratory. The latter observations were important for the development of home-cage testing in social groups, because they contradicted the traditional belief that animals must be tested under social isolation to prevent disturbance by other group members. The use of IntelliCages reduced indeed the amount of classic testing remarkably, while its flexibility was proved in a wide range of applications worldwide including transcontinental parallel testing. Essentially, two lines of testing emerged: sophisticated analysis of spontaneous behavior in the IntelliCage for screening of new genetic models, and hypothesis testing in many fields of behavioral neuroscience. Upcoming developments of the IntelliCage aim at improved stimulus presentation in the learning corners and videotracking of social interactions within the IntelliCage. Its main advantages are (i) that mice live in social context and are not stressfully handled for experiments, (ii) that studies are not restricted in time and can run in absence of humans, (iii) that it increases reproducibility of behavioral phenotyping worldwide, and (iv) that the industrial standardization of the cage permits retrospective data analysis with new statistical tools even after many years.
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Affiliation(s)
- Hans-Peter Lipp
- Faculty of Medicine, Institute of Evolutionary Medicine, University of Zürich, Zürich, Switzerland
| | - Sven Krackow
- Institute of Pathology and Molecular Pathology, University Hospital Zürich, Zürich, Switzerland
| | - Emir Turkes
- Queen Square Institute of Neurology, University College London, London, United Kingdom
| | - Seico Benner
- Center for Health and Environmental Risk Research, National Institute for Environmental Studies, Ibaraki, Japan
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Majid R, Al Talebi ZA, Al-Kawaz HS, Hassan Alta'ee A, Alsalman ARS, Hadwan AM, Hadwan MM, Hadwan MH. Novel fluorometric protocol for assessing myeloperoxidase activity. Enzyme Microb Technol 2023; 171:110320. [PMID: 37703636 DOI: 10.1016/j.enzmictec.2023.110320] [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: 07/07/2023] [Revised: 08/17/2023] [Accepted: 09/01/2023] [Indexed: 09/15/2023]
Abstract
Neutrophil myeloperoxidase (MPO) is an essential enzyme for the innate immune system. Measuring MPO activity is vital for understanding neutrophil characteristics and functions in various diseases. MPO activity can be measured using several methods, including spectrophotometric and fluorometric protocols. This paper introduces a fluorometric method for specifically quantifying MPO activity based on the H2O2-dependent oxidation of thiamine. We optimized this new method using the robust statistical approach response surface methodology (RSM) and Box Benken Design (BBD). We extensively examined the effects of several experimental parameters using the RSM methodology and determined the best conditions for accurate and sensitive MPO activity measurement. The optimal conditions were determined using the analysis of variance (ANOVA) for second-order polynomial equations. The resulting F-value (4.86) indicated that the model was significant. However, the lack-of-fitness F-value (1.79) suggested it did not differ significantly from the corresponding p-value. The greatest MPO activity (30 ± 2 U L-1) was obtained under optimum conditions, which were 1000 µM of H2O2, 10 min incubation time, and 1000 µM of thiamine. Our results suggest that this advanced fluorometric method has significant accuracy, sensitivity, and linearity up to 60 IU. The new and standard colorimetric methods also showed a good correlation. These results indicate that the new fluorometric method can be dependable and efficient for assessing MPO activity. The new method is characterized by excellent accuracy, sensitivity, and linearity, making it a valuable protocol for researchers and clinicians interested in assessing MPO activity.
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Affiliation(s)
- Rawa Majid
- Department of Medical Physics, University of Al-Mustaqbal, Hilla City, Babylon Governorate p.o. 51001, Iraq
| | - Zainab Abbas Al Talebi
- Chemistry Dept., College of Science, University of Babylon, Hilla City, Babylon Governorate p.o. 51002, Iraq
| | - Hawraa Saad Al-Kawaz
- Department of Pathological Analysis, College of Science, Al-Qasim Green University, 51013, Iraq
| | | | | | - Asad M Hadwan
- Faculty of Medicine, Golestan University of Medical Sciences, Gorgan, Iran; Al-Manara College for Medical Sciences, Al-Amarah City, Iraq
| | - Muntadhar M Hadwan
- College of Medicine, University of Babylon, Hilla City, Babylon Governorate, Iraq
| | - Mahmoud Hussein Hadwan
- Chemistry Dept., College of Science, University of Babylon, Hilla City, Babylon Governorate p.o. 51002, Iraq.
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Claeys W, Verhaege D, Van Imschoot G, Van Wonterghem E, Van Acker L, Amelinck L, De Ponti FF, Scott C, Geerts A, Van Steenkiste C, Van Hoecke L, Vandenbroucke RE. Limitations of PLX3397 as a microglial investigational tool: peripheral and off-target effects dictate the response to inflammation. Front Immunol 2023; 14:1283711. [PMID: 38077359 PMCID: PMC10703484 DOI: 10.3389/fimmu.2023.1283711] [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: 08/26/2023] [Accepted: 10/23/2023] [Indexed: 12/18/2023] Open
Abstract
Microglia, the resident macrophages of the central nervous system (CNS), play a critical role in CNS homeostasis and neuroinflammation. Pexidartinib (PLX3397), a colony-stimulating factor 1 (CSF1) receptor inhibitor, is widely used to deplete microglia, offering flexible options for both long-term depletion and highly versatile depletion-repopulation cycles. However, the potential impact of PLX3397 on peripheral (immune) cells remains controversial. Until now, the microglia-specificity of this type of compounds has not been thoroughly evaluated, particularly in the context of peripherally derived neuroinflammation. Our study addresses this gap by examining the effects of PLX3397 on immune cells in the brain, liver, circulation and bone marrow, both in homeostasis and systemic inflammation models. Intriguingly, we demonstrate that PLX3397 treatment not only influences the levels of tissue-resident macrophages, but also affects circulating and bone marrow immune cells beyond the mononuclear phagocyte system (MPS). These alterations in peripheral immune cells disrupt the response to systemic inflammation, consequently impacting the phenotype irrespective of microglial depletion. Furthermore, we observed that a lower dose of PLX3397, which does not deplete microglia, demonstrates similar (non-)MPS effects, both in the periphery and the brain, but fails to fully replicate the peripheral alterations seen in the higher doses, questioning lower doses as a 'peripheral control' strategy. Overall, our data highlight the need for caution when interpreting studies employing this compound, as it may not be suitable for specific investigation of microglial function in the presence of systemic inflammation.
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Affiliation(s)
- Wouter Claeys
- Department of Internal Medicine and Paediatrics, Hepatology Research Unit, Ghent University, Ghent, Belgium
- Liver Research Center Ghent, Ghent University, Ghent University Hospital, Ghent, Belgium
- Barriers in Inflammation, VIB-UGent Center for Inflammation Research, VIB, Ghent, Belgium
- Department of Biomedical Molecular Biology, Ghent University, Ghent, Belgium
| | - Daan Verhaege
- Barriers in Inflammation, VIB-UGent Center for Inflammation Research, VIB, Ghent, Belgium
- Department of Biomedical Molecular Biology, Ghent University, Ghent, Belgium
| | - Griet Van Imschoot
- Barriers in Inflammation, VIB-UGent Center for Inflammation Research, VIB, Ghent, Belgium
- Department of Biomedical Molecular Biology, Ghent University, Ghent, Belgium
| | - Elien Van Wonterghem
- Barriers in Inflammation, VIB-UGent Center for Inflammation Research, VIB, Ghent, Belgium
- Department of Biomedical Molecular Biology, Ghent University, Ghent, Belgium
| | - Lore Van Acker
- Barriers in Inflammation, VIB-UGent Center for Inflammation Research, VIB, Ghent, Belgium
- Department of Biomedical Molecular Biology, Ghent University, Ghent, Belgium
| | - Laura Amelinck
- Barriers in Inflammation, VIB-UGent Center for Inflammation Research, VIB, Ghent, Belgium
- Department of Biomedical Molecular Biology, Ghent University, Ghent, Belgium
| | - Federico F. De Ponti
- Department of Biomedical Molecular Biology, Ghent University, Ghent, Belgium
- Laboratory of Myeloid Cell Biology in Tissue Damage and Inflammation, VIB–UGent Center for Inflammation Research, Ghent, Belgium
| | - Charlotte Scott
- Department of Biomedical Molecular Biology, Ghent University, Ghent, Belgium
- Laboratory of Myeloid Cell Biology in Tissue Damage and Inflammation, VIB–UGent Center for Inflammation Research, Ghent, Belgium
| | - Anja Geerts
- Department of Internal Medicine and Paediatrics, Hepatology Research Unit, Ghent University, Ghent, Belgium
- Liver Research Center Ghent, Ghent University, Ghent University Hospital, Ghent, Belgium
- Department of Gastroenterology and Hepatology, Ghent University Hospital, Ghent, Belgium
| | - Christophe Van Steenkiste
- Antwerp University, Department of Gastroenterology and Hepatology, Antwerp, Belgium
- Department of Gastroenterology and Hepatology, Maria Middelares Hospital, Ghent, Belgium
| | - Lien Van Hoecke
- Barriers in Inflammation, VIB-UGent Center for Inflammation Research, VIB, Ghent, Belgium
- Department of Biomedical Molecular Biology, Ghent University, Ghent, Belgium
| | - Roosmarijn E. Vandenbroucke
- Barriers in Inflammation, VIB-UGent Center for Inflammation Research, VIB, Ghent, Belgium
- Department of Biomedical Molecular Biology, Ghent University, Ghent, Belgium
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Salken I, Provencio JJ, Coulibaly AP. A potential therapeutic target: The role of neutrophils in the central nervous system. Brain Behav Immun Health 2023; 33:100688. [PMID: 37767236 PMCID: PMC10520304 DOI: 10.1016/j.bbih.2023.100688] [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: 12/08/2022] [Revised: 09/14/2023] [Accepted: 09/16/2023] [Indexed: 09/29/2023] Open
Abstract
Neutrophils play a critical role in immune defense as the first recruited and most abundant leukocytes in the innate immune system. As such, regulation of neutrophil effector functions have strong implications on immunity. These cells display a wide heterogeneity of function, including both inflammatory and immunomodulatory roles. Neutrophils commonly infiltrate the central nervous system (CNS) in response to varied pathological conditions. There is still little understanding of the role these cells play in the CNS in such conditions. In the present review, we will summarize what is known of neutrophil's role in cancer and Alzheimer's disease (AD), with a focus on highlighting the gaps in our understanding.
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Affiliation(s)
- Isabel Salken
- College of Arts and Science, University of Virginia, USA
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Cho K. Neutrophil-Mediated Progression of Mild Cognitive Impairment to Dementia. Int J Mol Sci 2023; 24:14795. [PMID: 37834242 PMCID: PMC10572848 DOI: 10.3390/ijms241914795] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2023] [Revised: 09/26/2023] [Accepted: 09/29/2023] [Indexed: 10/15/2023] Open
Abstract
Cognitive impairment is a serious condition that begins with amnesia and progresses to cognitive decline, behavioral dysfunction, and neuropsychiatric impairment. In the final stage, dysphagia and incontinence occur. There are numerous studies and developed drugs for cognitive dysfunction in neurodegenerative diseases, such as Alzheimer's disease (AD); however, their clinical effectiveness remains equivocal. To date, attempts have been made to overcome cognitive dysfunction and understand and delay the aging processes that lead to degenerative and chronic diseases. Cognitive dysfunction is involved in aging and the disruption of inflammation and innate immunity. Recent reports have indicated that the innate immune system is prevalent in patients with AD, and that peripheral neutrophil markers can predict a decline in executive function in patients with mild cognitive impairment (MCI). Furthermore, altered levels of pro-inflammatory interleukins have been reported in MCI, which have been suggested to play a role in the peripheral immune system during the process from early MCI to dementia. Neutrophils are the first responders of the innate immune system. Neutrophils eliminate harmful cellular debris via phagocytosis, secrete inflammatory factors to activate host defense systems, stimulate cytokine production, kill pathogens, and regulate extracellular proteases and inhibitors. This review investigated and summarized the regulation of neutrophil function during cognitive impairment caused by various degenerative diseases. In addition, this work elucidates the cellular mechanism of neutrophils in cognitive impairment and what is currently known about the effects of activated neutrophils on cognitive decline.
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Affiliation(s)
- KyoungJoo Cho
- Department of Life Science, Kyonggi University, Suwon 16227, Republic of Korea
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Chakraborty S, Tabrizi Z, Bhatt NN, Franciosa SA, Bracko O. A Brief Overview of Neutrophils in Neurological Diseases. Biomolecules 2023; 13:biom13050743. [PMID: 37238612 DOI: 10.3390/biom13050743] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2023] [Revised: 04/21/2023] [Accepted: 04/23/2023] [Indexed: 05/28/2023] Open
Abstract
Neutrophils are the most abundant leukocyte in circulation and are the first line of defense after an infection or injury. Neutrophils have a broad spectrum of functions, including phagocytosis of microorganisms, the release of pro-inflammatory cytokines and chemokines, oxidative burst, and the formation of neutrophil extracellular traps. Traditionally, neutrophils were thought to be most important for acute inflammatory responses, with a short half-life and a more static response to infections and injury. However, this view has changed in recent years showing neutrophil heterogeneity and dynamics, indicating a much more regulated and flexible response. Here we will discuss the role of neutrophils in aging and neurological disorders; specifically, we focus on recent data indicating the impact of neutrophils in chronic inflammatory processes and their contribution to neurological diseases. Lastly, we aim to conclude that reactive neutrophils directly contribute to increased vascular inflammation and age-related diseases.
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Affiliation(s)
| | - Zeynab Tabrizi
- Department of Biology, University of Miami, Coral Gables, FL 33146, USA
| | | | | | - Oliver Bracko
- Department of Biology, University of Miami, Coral Gables, FL 33146, USA
- Department of Neurology, University of Miami-Miller School of Medicine, Miami, FL 33136, USA
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Lukens JR, Williams JL. An introduction to neuroimmunology. Immunol Rev 2022; 311:5-8. [PMID: 36039857 PMCID: PMC9489657 DOI: 10.1111/imr.13133] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- John R. Lukens
- Center for Brain Immunology and Glia (BIG), Department of Neuroscience, University of Virginia, Charlottesville, VA, USA
| | - Jessica L. Williams
- Department of Neurosciences, Lerner Research Institute, Cleveland Clinic, Cleveland, Ohio, USA
- Brain Health Research Institute, Kent State University, Kent, Ohio, USA
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