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Gansemer BM, Rahman MT, Zhang Z, Green SH. Spiral ganglion neuron degeneration in aminoglycoside-deafened rats involves innate and adaptive immune responses not requiring complement. Front Mol Neurosci 2024; 17:1389816. [PMID: 38840777 PMCID: PMC11151750 DOI: 10.3389/fnmol.2024.1389816] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2024] [Accepted: 04/29/2024] [Indexed: 06/07/2024] Open
Abstract
Spiral ganglion neurons (SGNs) transmit auditory information from cochlear hair cells to the brain. SGNs are thus not only important for normal hearing, but also for effective functioning of cochlear implants, which stimulate SGNs when hair cells are missing. SGNs slowly degenerate following aminoglycoside-induced hair cell loss, a process thought to involve an immune response. However, the specific immune response pathways involved remain unknown. We used RNAseq to gain a deeper understanding immune-related and other transcriptomic changes that occur in the rat spiral ganglion after kanamycin-induced deafening. Among the immune and inflammatory genes that were selectively upregulated in deafened spiral ganglia, the complement cascade genes were prominent. We then assessed SGN survival, as well as immune cell numbers and activation, in the spiral ganglia of rats with a CRISPR-Cas9-mediated knockout of complement component 3 (C3). Similar to previous findings in our lab and other deafened rodent models, we observed an increase in macrophage number and increased expression of CD68, a marker of phagocytic activity and cell activation, in macrophages in the deafened ganglia. Moreover, we found an increase in MHCII expression on spiral ganglion macrophages and an increase in lymphocyte number in the deafened ganglia, suggestive of an adaptive immune response. However, C3 knockout did not affect SGN survival or increase in macrophage number/activation, implying that complement activation does not play a role in SGN death after deafening. Together, these data suggest that both innate and adaptive immune responses are activated in the deafened spiral ganglion, with the adaptive response directly contributing to cochlear neurodegeneration.
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Affiliation(s)
| | | | | | - Steven H. Green
- Department of Biology, University of Iowa, Iowa City, IA, United States
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2
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Liu W, Li H, Kämpfe Nordström C, Danckwardt-Lillieström N, Agrawal S, Ladak HM, Rask-Andersen H. Immuno-surveillance and protection of the human cochlea. Front Neurol 2024; 15:1355785. [PMID: 38817543 PMCID: PMC11137295 DOI: 10.3389/fneur.2024.1355785] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2023] [Accepted: 02/21/2024] [Indexed: 06/01/2024] Open
Abstract
Background Despite its location near infection-prone areas, the human inner ear demonstrates remarkable resilience. This suggests that there are inherent instruments deterring the invasion and spread of pathogens into the inner ear. Here, we combined high-resolution light microscopy, super-resolution immunohistochemistry (SR-SIM) and synchrotron phase contrast imaging (SR-PCI) to identify the protection and barrier systems in the various parts of the human inner ear, focusing on the lateral wall, spiral ganglion, and endolymphatic sac. Materials and methods Light microscopy was conducted on mid-modiolar, semi-thin sections, after direct glutaraldehyde/osmium tetroxide fixation. The tonotopic locations were estimated using SR-PCI and 3D reconstruction in cadaveric specimens. The sections were analyzed for leucocyte and macrophage activity, and the results were correlated with immunohistochemistry using confocal microscopy and SR-SIM. Results Light microscopy revealed unprecedented preservation of cell anatomy and several macrophage-like cells that were localized in the cochlea. Immunohistochemistry demonstrated IBA1 cells frequently co-expressing MHC II in the spiral ganglion, nerve fibers, lateral wall, spiral limbus, and tympanic covering layer at all cochlear turns as well as in the endolymphatic sac. RNAscope assays revealed extensive expression of fractalkine gene transcripts in type I spiral ganglion cells. CD4 and CD8 cells occasionally surrounded blood vessels in the modiolus and lateral wall. TMEM119 and P2Y12 were not expressed, indicating that the cells labeled with IBA1 were not microglia. The round window niche, compact basilar membrane, and secondary spiral lamina may form protective shields in the cochlear base. Discussion The results suggest that the human cochlea is surveilled by dwelling and circulating immune cells. Resident and blood-borne macrophages may initiate protective immune responses via chemokine signaling in the lateral wall, spiral lamina, and spiral ganglion at different frequency locations. Synchrotron imaging revealed intriguing protective barriers in the base of the cochlea. The role of the endolymphatic sac in human inner ear innate and adaptive immunity is discussed.
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Affiliation(s)
- Wei Liu
- Department of Surgical Sciences, Otorhinolaryngology and Head and Neck Surgery, Uppsala University, Uppsala, Sweden
| | - Hao Li
- Department of Surgical Sciences, Otorhinolaryngology and Head and Neck Surgery, Uppsala University, Uppsala, Sweden
| | - Charlotta Kämpfe Nordström
- Department of Surgical Sciences, Otorhinolaryngology and Head and Neck Surgery, Uppsala University, Uppsala, Sweden
| | | | - Sumit Agrawal
- Department of Otolaryngology-Head and Neck Surgery, Western University, London, ON, Canada
- Department of Medical Biophysics, Western University, London, ON, Canada
- Department of Electrical and Computer Engineering, Western University, London, ON, Canada
| | - Hanif M. Ladak
- Department of Otolaryngology-Head and Neck Surgery, Western University, London, ON, Canada
- Department of Medical Biophysics, Western University, London, ON, Canada
- Department of Electrical and Computer Engineering, Western University, London, ON, Canada
| | - Helge Rask-Andersen
- Department of Surgical Sciences, Otorhinolaryngology and Head and Neck Surgery, Uppsala University, Uppsala, Sweden
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Razmovski T, Brody KM, Stathopoulos D, Zhang D, Cho E, Hampson AJ, Collins A, Bester C, O'Leary S. Intra-cochlear Flushing Reduces Tissue Response to Cochlear Implantation. Laryngoscope 2024; 134:1410-1416. [PMID: 37694764 DOI: 10.1002/lary.31022] [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: 03/15/2023] [Revised: 07/02/2023] [Accepted: 08/14/2023] [Indexed: 09/12/2023]
Abstract
INTRODUCTION Intraoperative trauma leading to bleeding during cochlear implantation negatively impacts residual hearing of cochlear implant recipients. There are no clinical protocols for the removal of blood during implantation, to reduce the consequential effects such as inflammation and fibrosis which adversely affect cochlear health and residual hearing. This preclinical study investigated the implementation of an intra-cochlear flushing protocol for the removal of blood. METHODS Three groups of guinea pigs were studied for 28 days after cochlear implantation; cochlear implant-only (control group); cochlear implant with blood injected into the cochlea (blood group); and cochlear implant, blood injection, and flushing of the blood from the cochlea intraoperatively (flush group). Auditory brainstem responses (ABRs) in addition to tissue response volumes were analyzed and compared between groups. RESULTS After implantation, the blood group exhibited the highest ABR thresholds when compared to the control and flush group, particularly in the high frequencies. On the final day, the control and blood group had similar ABR thresholds across all frequencies tested, whereas the flush group had the lowest thresholds, significantly lower at 24 kHz than the blood and control group. Analysis of the tissue response showed the flush group had significantly lower tissue responses in the basal half of the array when compared with the blood and control group. CONCLUSIONS Flushing intra-cochlear blood during surgery resulted in better auditory function and reduced subsequent fibrosis in the basal region of the cochlea. This finding prompts the implementation of a flushing protocol in clinical cochlear implantation. LEVEL OF EVIDENCE N/A Laryngoscope, 134:1410-1416, 2024.
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Affiliation(s)
- Tayla Razmovski
- Otolaryngology, Department of Surgery, Royal Victorian Eye and Ear Hospital, University of Melbourne, East Melbourne, Victoria, Australia
| | - Kate M Brody
- Otolaryngology, Department of Surgery, Royal Victorian Eye and Ear Hospital, University of Melbourne, East Melbourne, Victoria, Australia
| | - Dimitra Stathopoulos
- Otolaryngology, Department of Surgery, Royal Victorian Eye and Ear Hospital, University of Melbourne, East Melbourne, Victoria, Australia
| | - Dongcheng Zhang
- Otolaryngology, Department of Surgery, Royal Victorian Eye and Ear Hospital, University of Melbourne, East Melbourne, Victoria, Australia
| | - Ellie Cho
- Biological Optical Microscopy Platform, University of Melbourne, Parkville, Victoria, Australia
| | - Amy J Hampson
- Otolaryngology, Department of Surgery, Royal Victorian Eye and Ear Hospital, University of Melbourne, East Melbourne, Victoria, Australia
| | - Aaron Collins
- Otolaryngology, Department of Surgery, Royal Victorian Eye and Ear Hospital, University of Melbourne, East Melbourne, Victoria, Australia
| | - Christofer Bester
- Otolaryngology, Department of Surgery, Royal Victorian Eye and Ear Hospital, University of Melbourne, East Melbourne, Victoria, Australia
| | - Stephen O'Leary
- Otolaryngology, Department of Surgery, Royal Victorian Eye and Ear Hospital, University of Melbourne, East Melbourne, Victoria, Australia
- The Royal Victorian Eye and Ear Hospital, East Melbourne, Victoria, Australia
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4
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Zhang Y, Ye F, Fu X, Li S, Wang L, Chen Y, Li H, Hao S, Zhao K, Feng Q, Li P. Mitochondrial Regulation of Macrophages in Innate Immunity and Diverse Roles of Macrophages During Cochlear Inflammation. Neurosci Bull 2024; 40:255-267. [PMID: 37391607 PMCID: PMC10838870 DOI: 10.1007/s12264-023-01085-y] [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: 02/14/2023] [Accepted: 05/05/2023] [Indexed: 07/02/2023] Open
Abstract
Macrophages are essential components of the innate immune system and constitute a non-specific first line of host defense against pathogens and inflammation. Mitochondria regulate macrophage activation and innate immune responses in various inflammatory diseases, including cochlear inflammation. The distribution, number, and morphological characteristics of cochlear macrophages change significantly across different inner ear regions under various pathological conditions, including noise exposure, ototoxicity, and age-related degeneration. However, the exact mechanism underlying the role of mitochondria in macrophages in auditory function remains unclear. Here, we summarize the major factors and mitochondrial signaling pathways (e.g., metabolism, mitochondrial reactive oxygen species, mitochondrial DNA, and the inflammasome) that influence macrophage activation in the innate immune response. In particular, we focus on the properties of cochlear macrophages, activated signaling pathways, and the secretion of inflammatory cytokines after acoustic injury. We hope this review will provide new perspectives and a basis for future research on cochlear inflammation.
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Affiliation(s)
- Yuan Zhang
- Department of Otology, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, 450052, China
| | - Fanglei Ye
- Department of Otology, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, 450052, China
| | - Xiaolong Fu
- Shandong Provincial Hospital, Shandong First Medical University, Jinan, 250000, China
| | - Shen Li
- Department of Neurology, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, 450052, China
| | - Le Wang
- Department of Otology, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, 450052, China
| | - Yutian Chen
- The Department of Endovascular Surgery, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, 450052, China
| | - Hongmin Li
- Department of Otology, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, 450052, China
| | - Shaojuan Hao
- Department of Otology, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, 450052, China
| | - Kun Zhao
- Department of Otology, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, 450052, China
| | - Qi Feng
- Department of Integrated Traditional and Western Nephrology, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, 450052, China.
- Henan Province Research Center of Kidney Disease, Zhengzhou, 450052, China.
| | - Peipei Li
- Department of Integrated Traditional and Western Nephrology, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, 450052, China.
- Henan Province Research Center of Kidney Disease, Zhengzhou, 450052, China.
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5
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Miwa T, Rengasamy G, Liu Z, Ginhoux F, Okano T. Contribution of circulating monocytes in maintaining homeostasis of resident macrophages in postnatal and young adult mouse cochlea. Sci Rep 2024; 14:62. [PMID: 38167979 PMCID: PMC10762055 DOI: 10.1038/s41598-023-50634-y] [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: 09/01/2023] [Accepted: 12/22/2023] [Indexed: 01/05/2024] Open
Abstract
The percentage of macrophage subpopulations based on their origins in the adult cochlea remains unclear. This study aimed to elucidate the origins of cochlear macrophages during the onset phase and development of auditory function. We used three types of mice: wildtype ICR mice, colony-stimulating factor 1 receptor (Csf1r)-deficient mice, and Ms4a3Cre-Rosa tdTomato (Ms4a3tdT) transgenic mice. Macrophages were labeled with ionized calcium-binding adapter molecule 1 (Iba1), which is specific to more mature macrophages, and CD11b, which is specific to monocyte lineage. We investigated the spatial and temporal distribution patterns of resident macrophages in the cochlea during the postnatal and early adult stages. During the adult stages, the rate of monocytes recruited from the systemic circulation increased; moreover, Iba1+/CD11b- cochlear macrophages gradually decreased with age. Fate mapping of monocytes using Ms4a3tdT transgenic mice revealed an increased proportion of bone marrow-derived cochlear macrophages in the adult stage. Contrastingly, the proportion of yolk sac- and fetal liver-derived tissue-resident macrophages decreased steadily with age. This heterogeneity could be attributed to differences in environmental niches within the tissue or at the sub-tissue levels. Future studies should investigate the role of cochlear macrophages in homeostasis, inflammation, and other diseases, including infection, autoimmune, and metabolic diseases.
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Affiliation(s)
- Toru Miwa
- Department of Otolaryngology, Head and Neck Surgery, Graduate School of Medicine, Kyoto University, Sakyo-ku, Kyoto, Japan.
- Department of Otolaryngology-Head and Neck Surgery, Osaka Metropolitan University, Abeno-ku, Osaka, Japan.
| | - Gowshika Rengasamy
- Singapore Immunology Network, Agency for Science, Technology and Research, Singapore, Singapore
| | - Zhaoyuan Liu
- Shanghai Institute of Immunology, Department of Immunology and Microbiology, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Florent Ginhoux
- Singapore Immunology Network, Agency for Science, Technology and Research, Singapore, Singapore
- Shanghai Institute of Immunology, Department of Immunology and Microbiology, Shanghai Jiao Tong University School of Medicine, Shanghai, China
- SingHealth Duke-NUS Academic Medical Centre, Translational Immunology Institute, Singapore, Singapore
- Institut Gustave Roussy, INSERM U1015, Villejuif, France
| | - Takayuki Okano
- Department of Otolaryngology, Head and Neck Surgery, Graduate School of Medicine, Kyoto University, Sakyo-ku, Kyoto, Japan
- Department of Otolaryngology-Head and Neck Surgery, Fujita Health University, Toyoake, Aichi, Japan
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6
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Liu Y, Yang L, Singh S, Beyer LA, Prieskorn DM, Swiderski DL, Groves AK, Raphael Y. Combinatorial Atoh1, Gfi1, Pou4f3, and Six1 gene transfer induces hair cell regeneration in the flat epithelium of mature guinea pigs. Hear Res 2024; 441:108916. [PMID: 38103445 PMCID: PMC11223172 DOI: 10.1016/j.heares.2023.108916] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/05/2023] [Revised: 10/29/2023] [Accepted: 11/14/2023] [Indexed: 12/19/2023]
Abstract
Flat epithelium (FE) is a condition characterized by the loss of both hair cells (HCs) and supporting cells and the transformation of the organ of Corti into a simple flat or cuboidal epithelium, which can occur after severe cochlear insults. The transcription factors Gfi1, Atoh1, Pou4f3, and Six1 (GAPS) play key roles in HC differentiation and survival in normal ears. Previous work using a single transcription factor, Atoh1, to induce HC regeneration in mature ears in vivo usually produced very few cells and failed to produce HCs in severely damaged organs of Corti, especially those with FE. Studies in vitro suggested combinations of transcription factors may be more effective than any single factor, thus the current study aims to examine the effect of co-overexpressing GAPS genes in deafened mature guinea pig cochleae with FE. Deafening was achieved through the infusion of neomycin into the perilymph, leading to the formation of FE and substantial degeneration of nerve fibers. Seven days post neomycin treatment, adenovirus vectors carrying GAPS were injected into the scala media and successfully expressed in the FE. One or two months following GAPS inoculation, cells expressing Myosin VIIa were observed in regions under the FE (located at the scala tympani side of the basilar membrane), rather than within the FE. The number of cells, which we define as induced HCs (iHCs), was not significantly different between one and two months, but the larger N at two months made it more apparent that there were significantly more iHCs in GAPS treated animals than in controls. Additionally, qualitative observations indicated that ears with GAPS gene expression in the FE had more nerve fibers than FE without the treatment. In summary, our results showed that co-overexpression of GAPS enhances the potential for HC regeneration in a severe lesion model of FE.
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Affiliation(s)
- Yujie Liu
- Kresge Hearing Research Institute, Department of Otolaryngology-Head and Neck Surgery, University of Michigan, Ann Arbor, MI, USA; Department of Otolaryngology-Head and Neck Surgery, Beijing Tongren Hospital, Capital Medical University, Ministry of Education Key Laboratory of Otolaryngology-Head and Neck Surgery, Beijing 100730, China
| | - Lin Yang
- Kresge Hearing Research Institute, Department of Otolaryngology-Head and Neck Surgery, University of Michigan, Ann Arbor, MI, USA; Department of Otolaryngology-Head and Neck Surgery, Beijing Tiantan Hospital, Capital Medical University, Beijing 100070, China
| | - Sunita Singh
- Department of Neuroscience, Baylor College of Medicine, Houston, Texas, USA
| | - Lisa A Beyer
- Kresge Hearing Research Institute, Department of Otolaryngology-Head and Neck Surgery, University of Michigan, Ann Arbor, MI, USA
| | - Diane M Prieskorn
- Kresge Hearing Research Institute, Department of Otolaryngology-Head and Neck Surgery, University of Michigan, Ann Arbor, MI, USA
| | - Donald L Swiderski
- Kresge Hearing Research Institute, Department of Otolaryngology-Head and Neck Surgery, University of Michigan, Ann Arbor, MI, USA
| | - Andrew K Groves
- Department of Neuroscience, Baylor College of Medicine, Houston, Texas, USA; Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas, USA
| | - Yehoash Raphael
- Kresge Hearing Research Institute, Department of Otolaryngology-Head and Neck Surgery, University of Michigan, Ann Arbor, MI, USA.
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Sung CYW, Hayase N, Yuen PST, Lee J, Fernandez K, Hu X, Cheng H, Star RA, Warchol ME, Cunningham LL. Macrophage Depletion Protects Against Cisplatin-Induced Ototoxicity and Nephrotoxicity. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.11.16.567274. [PMID: 38014097 PMCID: PMC10680818 DOI: 10.1101/2023.11.16.567274] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/29/2023]
Abstract
Cisplatin is a widely used and highly effective anti-cancer drug with significant side effects including ototoxicity and nephrotoxicity. Macrophages, the major resident immune cells in the cochlea and kidney, are important drivers of both inflammatory and tissue repair responses. To investigate the roles of macrophages in cisplatin-induced ototoxicity and nephrotoxicity, we used PLX3397, an FDA-approved inhibitor of the colony-stimulating factor 1 receptor (CSF1R), to eliminate tissue-resident macrophages during the course of cisplatin administration. Mice treated with cisplatin alone (cisplatin/vehicle) had significant hearing loss (ototoxicity) as well as kidney injury (nephrotoxicity). Macrophage ablation using PLX3397 resulted in significantly reduced hearing loss measured by auditory brainstem responses (ABR) and distortion-product otoacoustic emissions (DPOAE). Sensory hair cells in the cochlea were protected against cisplatin-induced death in mice treated with PLX3397. Macrophage ablation also protected against cisplatin-induced nephrotoxicity, as evidenced by markedly reduced tubular injury and fibrosis as well as reduced plasma blood urea nitrogen (BUN) and neutrophil gelatinase-associated lipocalin (NGAL) levels. Mechanistically, our data suggest that the protective effect of macrophage ablation against cisplatin-induced ototoxicity and nephrotoxicity is mediated by reduced platinum accumulation in both the inner ear and the kidney. Together our data indicate that ablation of tissue-resident macrophages represents a novel strategy for mitigating cisplatin-induced ototoxicity and nephrotoxicity. Brief summary Macrophage ablation using PLX3397 was protective against cisplatin-induced ototoxicity and nephrotoxicity by limiting platinum accumulation in the inner ear and kidney.
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8
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Zhang C, Ye M, Bush P, Hu BH. Heterogeneity in macrophages along the cochlear spiral in mice: insights from SEM and functional analyses. Front Cell Neurosci 2023; 17:1222074. [PMID: 37692550 PMCID: PMC10485373 DOI: 10.3389/fncel.2023.1222074] [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: 05/18/2023] [Accepted: 07/31/2023] [Indexed: 09/12/2023] Open
Abstract
The susceptibility of sensory cells to pathological conditions differs between the apical and basal regions of the cochlea, and the cochlear immune system may contribute to this location-dependent variability. Our previous study found morphological differences in basilar membrane macrophages between the apical and basal regions of the cochlea. However, the details of this site-dependent difference and its underlying structural and biological basis are not fully understood. In this study, we utilized scanning electron microscopy to examine the ultrastructure of macrophages and their surrounding supporting structures. Additionally, we examined the phagocytic activities of macrophages and the expression of immune molecules in both apical and basal regions of the cochlea. We employed two mouse strains (C57BL/6J and B6.129P-Cx3cr1tm1Litt/J) and evaluated three experimental conditions: young normal (1-4 months), aging (11-19 months), and noise-induced damage (120 dB SPL for 1 h). Using scanning electron microscopy, we revealed location-specific differences in basilar membrane macrophage morphology and surface texture, architecture in mesothelial cell layers, and spatial correlation between macrophages and mesothelial cells in both young and older mice. Observations of macrophage phagocytic activities demonstrated that basal macrophages exhibited greater phagocytic activities in aging and noise-damaged ears. Furthermore, we identified differences in the expression of immune molecules between the apical and basal cochlear tissues of young mice. Finally, our study demonstrated that as the cochlea ages, macrophages in the apical and basal regions undergo a transformation in their morphologies, with apical macrophages acquiring certain basal macrophage features and vice versa. Overall, our findings demonstrate apical and basal differences in macrophage phenotypes and functionality, which are related to distinct immune and structural differences in the macrophage surrounding tissues.
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Affiliation(s)
- Celia Zhang
- Department of Communicative Disorders and Sciences, University at Buffalo, Buffalo, NY, United States
- Department of Audiology, University of the Pacific, San Francisco, CA, United States
| | - Mengxiao Ye
- Department of Communicative Disorders and Sciences, University at Buffalo, Buffalo, NY, United States
| | - Peter Bush
- South Campus Instrument Center, University at Buffalo, Buffalo, NY, United States
| | - Bo Hua Hu
- Department of Communicative Disorders and Sciences, University at Buffalo, Buffalo, NY, United States
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9
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Hosoya M, Kitama T, Shimanuki MN, Nishiyama T, Oishi N, Okano H, Ozawa H. Distribution of macrophages in the developing cochlea of the common marmoset, a primate model animal. Front Immunol 2023; 14:1229414. [PMID: 37675123 PMCID: PMC10477578 DOI: 10.3389/fimmu.2023.1229414] [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: 05/26/2023] [Accepted: 08/04/2023] [Indexed: 09/08/2023] Open
Abstract
Introduction Macrophages are essential immune cells in the cochlea that contribute to inflammation, tissue repair, and homeostasis. They also play an important role in local cochlear immunity. The developmental immigration and maturation of macrophages in the cochlea have been investigated and are considered essential for normal hearing acquisition. Most of our current knowledge regarding cochlear development is based on rodent models because of the ethical challenges of using human fetal samples for research. However, inter-species differences between rodents and humans have been reported. In this study, we used a primate animal model to investigate the distributions of macrophages in the developing cochlea. The common marmoset (Callithrix jacchus), a small monkey species that inhabits the New World, was used as the model. Methods We investigated the distribution of macrophages in the developing cochlea of the common marmoset by performing immunohistochemical analyses of cochlear tissue from common marmoset embryos at different development stages. Results We revealed detailed distribution changes in the macrophages of a primate animal model cochlea. This observation indicates that most of the changes in the general distribution of macrophages were well preserved between rodents and this primate. The distribution changes observed in the common marmoset were also compatible with observations in the human fetus; although, observations in the human fetus are limited. Our observations in this study also revealed several differences between common marmosets and rodents. Conclusion The time course of immunological development and maturations established in this study will aid in the study of the primate-specific developmental biology of the inner ear. These observations may eventually lead to new therapeutic strategies for hearing loss in humans. In addition, understanding the immunological steady-state of the cochlea may help in the study of age- and genetic-induced hearing loss and in the design of regenerative therapies.
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Affiliation(s)
- Makoto Hosoya
- Department of Otorhinolaryngology, Head and Neck Surgery, Keio University School of Medicine, Tokyo, Japan
| | - Tsubasa Kitama
- Department of Otorhinolaryngology, Head and Neck Surgery, Keio University School of Medicine, Tokyo, Japan
| | - Marie N. Shimanuki
- Department of Otorhinolaryngology, Head and Neck Surgery, Keio University School of Medicine, Tokyo, Japan
| | - Takanori Nishiyama
- Department of Otorhinolaryngology, Head and Neck Surgery, Keio University School of Medicine, Tokyo, Japan
| | - Naoki Oishi
- Department of Otorhinolaryngology, Head and Neck Surgery, Keio University School of Medicine, Tokyo, Japan
| | - Hideyuki Okano
- Department of Physiology, Keio University School of Medicine, Tokyo, Japan
- Laboratory for Marmoset Neural Architecture, Center for Brain Science, RIKEN, Saitama, Japan
| | - Hiroyuki Ozawa
- Department of Otorhinolaryngology, Head and Neck Surgery, Keio University School of Medicine, Tokyo, Japan
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10
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Brown LN, Barth JL, Jafri S, Rumschlag JA, Jenkins TR, Atkinson C, Lang H. Complement factor B is essential for the proper function of the peripheral auditory system. Front Neurol 2023; 14:1214408. [PMID: 37560455 PMCID: PMC10408708 DOI: 10.3389/fneur.2023.1214408] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2023] [Accepted: 07/05/2023] [Indexed: 08/11/2023] Open
Abstract
Sensorineural hearing loss is associated with dysfunction of cochlear cells. Although immune cells play a critical role in maintaining the inner ear microenvironment, the precise immune-related molecular mechanisms underlying the pathophysiology of hearing loss remain unclear. The complement cascade contributes to the regulation of immune cell activity. Additionally, activation of the complement cascade can lead to the cellular opsonization of cells and pathogens, resulting in their engulfment and elimination by phagocytes. Complement factor B (fB) is an essential activator protein in the alternative complement pathway, and variations in the fB gene are associated with age-related macular degeneration. Here we show that mice of both sexes deficient in fB functional alleles (fB-/-) demonstrate progressive hearing impairment. Transcriptomic analysis of auditory nerves from adult mice detected 706 genes that were significantly differentially expressed between fB-/- and wild-type control animals, including genes related to the extracellular matrix and neural development processes. Additionally, a subset of differentially expressed genes was related to myelin function and neural crest development. Histological and immunohistochemical investigations revealed pathological alterations in auditory nerve myelin sheathes of fB-/- mice. Pathological alterations were also seen in the stria vascularis of the cochlear lateral wall in these mice. Our results implicate fB as an integral regulator of myelin maintenance and stria vascularis integrity, underscoring the importance of understanding the involvement of immune signaling pathways in sensorineural hearing loss.
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Affiliation(s)
- LaShardai N. Brown
- Department of Pathology and Laboratory Medicine, Medical University of South Carolina, Charleston, SC, United States
| | - Jeremy L. Barth
- Department of Regenerative Medicine and Cell Biology, Medical University of South Carolina, Charleston, SC, United States
| | - Shabih Jafri
- Department of Pathology and Laboratory Medicine, Medical University of South Carolina, Charleston, SC, United States
| | - Jeffrey A. Rumschlag
- Department of Pathology and Laboratory Medicine, Medical University of South Carolina, Charleston, SC, United States
| | - Tyreek R. Jenkins
- Department of Pathology and Laboratory Medicine, Medical University of South Carolina, Charleston, SC, United States
| | - Carl Atkinson
- Division of Pulmonary Medicine, University of Florida, Gainesville, FL, United States
| | - Hainan Lang
- Department of Pathology and Laboratory Medicine, Medical University of South Carolina, Charleston, SC, United States
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Lang H, Noble KV, Barth JL, Rumschlag JA, Jenkins TR, Storm SL, Eckert MA, Dubno JR, Schulte BA. The Stria Vascularis in Mice and Humans Is an Early Site of Age-Related Cochlear Degeneration, Macrophage Dysfunction, and Inflammation. J Neurosci 2023; 43:5057-5075. [PMID: 37268417 PMCID: PMC10324995 DOI: 10.1523/jneurosci.2234-22.2023] [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: 12/05/2022] [Revised: 04/19/2023] [Accepted: 05/25/2023] [Indexed: 06/04/2023] Open
Abstract
Age-related hearing loss, or presbyacusis, is a common degenerative disorder affecting communication and quality of life for millions of older adults. Multiple pathophysiologic manifestations, along with many cellular and molecular alterations, have been linked to presbyacusis; however, the initial events and causal factors have not been clearly established. Comparisons of the transcriptome in the lateral wall (LW) with other cochlear regions in a mouse model (of both sexes) of "normal" age-related hearing loss revealed that early pathophysiological alterations in the stria vascularis (SV) are associated with increased macrophage activation and a molecular signature indicative of inflammaging, a common form of immune dysfunction. Structure-function correlation analyses in mice across the lifespan showed that the age-dependent increase in macrophage activation in the stria vascularis is associated with a decline in auditory sensitivity. High-resolution imaging analysis of macrophage activation in middle-aged and aged mouse and human cochleas, along with transcriptomic analysis of age-dependent changes in mouse cochlear macrophage gene expression, support the hypothesis that aberrant macrophage activity is an important contributor to age-dependent strial dysfunction, cochlear pathology, and hearing loss. Thus, this study highlights the SV as a primary site of age-related cochlear degeneration and aberrant macrophage activity and dysregulation of the immune system as early indicators of age-related cochlear pathology and hearing loss. Importantly, novel new imaging methods described here now provide a means to analyze human temporal bones in a way that had not previously been feasible and thereby represent a significant new tool for otopathological evaluation.SIGNIFICANCE STATEMENT Age-related hearing loss is a common neurodegenerative disorder affecting communication and quality of life. Current interventions (primarily hearing aids and cochlear implants) offer imperfect and often unsuccessful therapeutic outcomes. Identification of early pathology and causal factors is crucial for the development of new treatments and early diagnostic tests. Here, we find that the SV, a nonsensory component of the cochlea, is an early site of structural and functional pathology in mice and humans that is characterized by aberrant immune cell activity. We also establish a new technique for evaluating cochleas from human temporal bones, an important but understudied area of research because of a lack of well-preserved human specimens and difficult tissue preparation and processing approaches.
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Affiliation(s)
- Hainan Lang
- Department of Pathology and Laboratory Medicine, Medical University of South Carolina, Charleston, South Carolina 29425
| | - Kenyaria V Noble
- Department of Pathology and Laboratory Medicine, Medical University of South Carolina, Charleston, South Carolina 29425
| | - Jeremy L Barth
- Department of Regenerative Medicine and Cell Biology, Medical University of South Carolina, Charleston, South Carolina 29425
| | - Jeffrey A Rumschlag
- Department of Pathology and Laboratory Medicine, Medical University of South Carolina, Charleston, South Carolina 29425
| | - Tyreek R Jenkins
- Department of Pathology and Laboratory Medicine, Medical University of South Carolina, Charleston, South Carolina 29425
| | - Shelby L Storm
- Department of Pathology and Laboratory Medicine, Medical University of South Carolina, Charleston, South Carolina 29425
| | - Mark A Eckert
- Department of Otolaryngology-Head and Neck Surgery, Medical University of South Carolina, Charleston, South Carolina 29425
| | - Judy R Dubno
- Department of Otolaryngology-Head and Neck Surgery, Medical University of South Carolina, Charleston, South Carolina 29425
| | - Bradley A Schulte
- Department of Pathology and Laboratory Medicine, Medical University of South Carolina, Charleston, South Carolina 29425
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12
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Schiel V, Xia A, Santa Maria PL. Influence of CX3CR1 Deletion on Cochlear Hair Cell Survival and Macrophage Expression in Chronic Suppurative Otitis Media. Otol Neurotol 2023; 44:605-610. [PMID: 37315234 PMCID: PMC10275455 DOI: 10.1097/mao.0000000000003884] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/16/2023]
Abstract
OBJECTIVE Our objective was to determine whether the receptor CX3CR1 is necessary for the recruitment of macrophages to the cochlea in chronic suppurative otitis media (CSOM) and if its deletion can prevent hair cell loss in CSOM. BACKGROUND CSOM is a neglected disease that afflicts 330 million people worldwide and is the most common cause of permanent hearing loss among children in the developing world. It is characterized by a chronically discharging infected middle ear. We have previously demonstrated that CSOM causes macrophage associated sensory hearing loss. The receptor CX3CR1 is expressed on macrophages, which have been shown to be increased at the time point of outer hair cell (OHC) loss in CSOM. METHODS In this report, we examine the influence of CX3CR1 deletion (CX3CR1-/-) in a validated model of Pseudomonas aeruginosa (PA) CSOM. RESULTS The data show no difference in OHC loss between the CX3CR1-/- CSOM group and CX3CR1+/+ CSOM group (p = 0.28). We observed partial OHC loss in the cochlear basal turn, no OHC loss in the middle and apical turns in both CX3CR1-/- and CX3CR1+/+ CSOM mice at 14 days after bacterial inoculation. No inner hair cell (IHC) loss was found in all cochlear turns in all groups. We also counted F4/80 labeled macrophages in the spiral ganglion, spiral ligament, stria vascularis and spiral limbus of the basal, middle, and apical turn in cryosections. We did not find a significant difference in the total number of cochlear macrophages between CX3CR1-/- mice and CX3CR1+/+ mice (p = 0.97). CONCLUSION The data did not support a role for CX3CR1 macrophage associated HC loss in CSOM.
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Affiliation(s)
- Viktoria Schiel
- Department of Otolaryngology, Head and Neck Surgery, Stanford University, Palo Alto, California
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13
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Bader W, Steinacher C, Fischer HT, Glueckert R, Schmutzhard J, Schrott-Fischer A. Effects of Therapeutic Hypothermia on Macrophages in Mouse Cochlea Explants. Int J Mol Sci 2023; 24:8850. [PMID: 37240196 PMCID: PMC10218374 DOI: 10.3390/ijms24108850] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2023] [Revised: 05/04/2023] [Accepted: 05/15/2023] [Indexed: 05/28/2023] Open
Abstract
Globally, over the next few decades, more than 2.5 billion people will suffer from hearing impairment, including profound hearing loss, and millions could potentially benefit from a cochlea implant. To date, several studies have focused on tissue trauma caused by cochlea implantation. The direct immune reaction in the inner ear after an implantation has not been well studied. Recently, therapeutic hypothermia has been found to positively influence the inflammatory reaction caused by electrode insertion trauma. The present study aimed to evaluate the hypothermic effect on the structure, numbers, function and reactivity of macrophages and microglial cells. Therefore, the distribution and activated forms of macrophages in the cochlea were evaluated in an electrode insertion trauma cochlea culture model in normothermic and mild hypothermic conditions. In 10-day-old mouse cochleae, artificial electrode insertion trauma was inflicted, and then they were cultured for 24 h at 37 °C and 32 °C. The influence of mild hypothermia on macrophages was evaluated using immunostaining of cryosections using antibodies against IBA1, F4/80, CD45 and CD163. A clear influence of mild hypothermia on the distribution of activated and non-activated forms of macrophages and monocytes in the inner ear was observed. Furthermore, these cells were located in the mesenchymal tissue in and around the cochlea, and the activated forms were found in and around the spiral ganglion tissue at 37 °C. Our findings suggest that mild hypothermic treatment has a beneficial effect on immune system activation after electrode insertion trauma.
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Affiliation(s)
| | | | | | | | - Joachim Schmutzhard
- Department of Otorhinolaryngology, Medical University Innsbruck, 6020 Innsbruck, Austria; (W.B.); (C.S.); (H.T.F.); (R.G.); (A.S.-F.)
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14
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Findlay C, Edwards M, Hough K, Grasmeder M, Newman TA. Leveraging real-world data to improve cochlear implant outcomes: Is the data available? Cochlear Implants Int 2023:1-12. [PMID: 37088565 DOI: 10.1080/14670100.2023.2198792] [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: 04/25/2023]
Abstract
OBJECTIVES A small but persistent proportion of individuals do not gain the expected benefit from cochlear implants(CI). A step-change in the understanding of factors affecting outcomes could come through data science. This study evaluates clinical data capture to assess the quality and utility of CI user's health records for data science, by assessing the recording of otitis media. Otitis media was selected as it is associated with the development of sensorineural hearing loss and may affect cochlear implant outcomes. METHODS A retrospective service improvement project evaluating the medical records of 594 people with a CI under the care of the University of Southampton Auditory Implant Service between 2014 and 2020. RESULTS The clinical records are suitable for data science research. Of the cohort studied 20% of Adults and more than 40% of the paediatric cases have a history of middle ear inflammation. DISCUSSION Data science has potential to improve cochlear implant outcomes and improve understanding of the mechanisms underlying poor performance, through retrospective secondary analysis of real-world data. CONCLUSION Implant centres and the British Cochlear Implant Group National Hearing Implant Registry are urged to consider the importance of consistently and accurate recording of patient data over time for each CI user. Data where links to hearing loss have been identified, such as middle ear inflammation, may be particularly valuable in future analyses and to inform clinical trials.
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Affiliation(s)
- Callum Findlay
- Clinical and Experimental Sciences, Faculty of Medicine, University of Southampton, Building 85, Highfield Campus, Southampton S017 1BJ, UK
- Department of Otolaryngology, University Hospital Southampton NHS FT, Tremona Road, Southampton SO16 6YD, UK
| | - Mathew Edwards
- Clinical and Experimental Sciences, Faculty of Medicine, University of Southampton, Building 85, Highfield Campus, Southampton S017 1BJ, UK
| | - Kate Hough
- Faculty of Engineering and Physical Sciences, Highfield Campus, University of Southampton, Building 85, Southampton, UK
| | - Mary Grasmeder
- Faculty of Physical Sciences, Highfield Campus, University of Southampton Auditory Implant Services, B19, Southampton SO171BJ, UK
| | - Tracey A Newman
- Clinical and Experimental Sciences, Faculty of Medicine, University of Southampton, Building 85, Highfield Campus, Southampton S017 1BJ, UK
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Andrade da Silva LH, Heuer RA, Roque CB, McGuire TL, Hosoya T, Kimura H, Tamura K, Matsuoka AJ. Enhanced survival of hypoimmunogenic otic progenitors following intracochlear xenotransplantation: repercussions for stem cell therapy in hearing loss models. Stem Cell Res Ther 2023; 14:83. [PMID: 37046329 PMCID: PMC10099643 DOI: 10.1186/s13287-023-03304-9] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2022] [Accepted: 03/28/2023] [Indexed: 04/14/2023] Open
Abstract
Stem cell replacement holds the potential for sensorineural hearing loss (SNHL) treatment. However, its translation into clinical practice requires strategies for improving stem cell survival following intracochlear transplantation. Considering recent findings showing that the inner ear contains a resident population of immune cells, we hypothesized that immune evasion would improve the survival and residence time of transplanted stem cells in the cochlea, potentially leading to better outcomes. To test this, we leveraged genetic engineering techniques to develop hypoimmunogenic human-induced pluripotent stem cells (hi-iPSC), which lack human leukocyte antigen expression. We found that gene editing does not affect the biological properties of hi-iPSCs, including their capacity to differentiate into otic neural progenitors (ONPs). Compared to wild-type ONPs, more hypoimmunogenic ONPs (derived from hi-iPSCs) were found in the inner ear of immunocompetent mice ten days following cochlear xenotransplantation. This approach may open a new avenue for experimental and clinical SNHL treatments.
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Affiliation(s)
- Luisa H Andrade da Silva
- Department of Otolaryngology and Head and Neck Surgery, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA
| | - Rachel A Heuer
- Department of Otolaryngology and Head and Neck Surgery, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA
| | - Christian B Roque
- Department of Otolaryngology and Head and Neck Surgery, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA
| | - Tammy L McGuire
- Department of Neurology, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA
| | | | | | - Kouichi Tamura
- Kobe Research Institute, HEALIOS K.K., Kobe, Hyogo, Japan
| | - Akihiro J Matsuoka
- Department of Otolaryngology and Head and Neck Surgery, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA.
- Roxelyn and Richard Pepper Department of Communication Sciences and Disorders, School of Communication, Northwestern University, Evanston, IL, USA.
- Hugh Knowles Center for Clinical and Basic Science in Hearing and Its Disorders, Evanston, IL, USA.
- Center for Advanced Regenerative Engineering, Northwestern University, Evanston, IL, USA.
- Department of Otolaryngology and Head and Neck Surgery, University of California San Diego, 9444 Medical Center Drive, MC7895, La Jolla, CA, 92037, USA.
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Identification and Characterization of TMEM119-Positive Cells in the Postnatal and Adult Murine Cochlea. Brain Sci 2023; 13:brainsci13030516. [PMID: 36979326 PMCID: PMC10046579 DOI: 10.3390/brainsci13030516] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2023] [Revised: 03/09/2023] [Accepted: 03/18/2023] [Indexed: 03/22/2023] Open
Abstract
Transmembrane protein 119 (TMEM119) is expressed in a subset of resident macrophage cells of the brain and was proposed as a marker for native brain microglia. The presence of cells expressing TMEM119 in the cochlea has not yet been described. Thus, the present study aimed to characterize the TMEM119-expressing cells of the postnatal and adult cochlea, the latter also after noise exposure. Immunofluorescent staining of cochlear cryosections detected TMEM119 protein in the spiral limbus fibrocytes and the developing stria vascularis at postnatal Day 3. Applying the macrophage marker Iba1 revealed that TMEM119 is not a marker of cochlear macrophages or a subset of them. In the adult murine cochlea, TMEM119 expression was detected in the basal cells of the stria vascularis and the dark mesenchymal cells of the supralimbal zone. Exposure to noise trauma was not associated with a qualitative change in the types or distributions of the TMEM119-expressing cells of the adult cochlea. Western blot analysis indicated a similar TMEM119 protein expression level in the postnatal cochlea and brain tissues. The findings do not support using TMEM119 as a specific microglial or macrophage marker in the cochlea. The precise role of TMEM119 in the cochlea remains to be investigated through functional experiments. TMEM119 expression in the basal cells of the stria vascularis implies a possible role in the gap junction system of the blood–labyrinth barrier and merits further research.
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17
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Serum/glucocorticoid-inducible kinase 1 deficiency induces NLRP3 inflammasome activation and autoinflammation of macrophages in a murine endolymphatic hydrops model. Nat Commun 2023; 14:1249. [PMID: 36872329 PMCID: PMC9986248 DOI: 10.1038/s41467-023-36949-4] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2022] [Accepted: 02/24/2023] [Indexed: 03/07/2023] Open
Abstract
Ménière's disease, a multifactorial disorder of the inner ear, is characterized by severe vertigo episodes and hearing loss. Although the role of immune responses in Ménière's disease has been proposed, the precise mechanisms remain undefined. Here, we show that downregulation of serum/glucocorticoid-inducible kinase 1 is associated with activation of NLRP3 inflammasome in vestibular-resident macrophage-like cells from Ménière's disease patients. Serum/glucocorticoid-inducible kinase 1 depletion markedly enhances IL-1β production which leads to the damage of inner ear hair cells and vestibular nerve. Mechanistically, serum/glucocorticoid-inducible kinase 1 binds to the PYD domain of NLRP3 and phosphorylates it at Serine 5, thereby interfering inflammasome assembly. Sgk-/- mice show aggravated audiovestibular symptoms and enhanced inflammasome activation in lipopolysaccharide-induced endolymphatic hydrops model, which is ameliorated by blocking NLRP3. Pharmacological inhibition of serum/glucocorticoid-inducible kinase 1 increases the disease severity in vivo. Our studies demonstrate that serum/glucocorticoid-inducible kinase 1 functions as a physiologic inhibitor of NLRP3 inflammasome activation and maintains inner ear immune homeostasis, reciprocally participating in models of Ménière's disease pathogenesis.
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18
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Ishiyama P, Ishiyama G, Lopez IA, Ishiyama A. Archival Human Temporal Bone: Anatomical and Histopathological Studies of Cochlear Implantation. J Pers Med 2023; 13:352. [PMID: 36836587 PMCID: PMC9959196 DOI: 10.3390/jpm13020352] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2022] [Revised: 02/12/2023] [Accepted: 02/14/2023] [Indexed: 02/22/2023] Open
Abstract
Since being FDA approved in 1984, cochlear implantation has been used successfully to restore hearing in those with severe to profound hearing loss with broader applications including single-sided deafness, the use of hybrid electroacoustic stimulation, and implantation at all extremes of age. Cochlear implants have undergone multiple changes in the design aimed at improving the processing technology, while simultaneously minimizing the surgical trauma and foreign body reaction. The following review examines the human temporal bone studies regarding the anatomy of the human cochlea and how the anatomy relates to cochlear implant design, the factors related to complications after implantation, and the predictors of new tissue formation and osteoneogenesis. Histopathological studies are reviewed which aim to understand the potential implications of the effects of new tissue formation and inflammation following implantation.
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Affiliation(s)
- Paul Ishiyama
- Department of Head and Neck Surgery, David Geffen School of Medicine at UCLA, Los Angeles, CA 90095, USA
| | - Gail Ishiyama
- Department of Neurology, David Geffen School of Medicine at UCLA, Los Angeles, CA 90095, USA
| | - Ivan A. Lopez
- Department of Head and Neck Surgery, David Geffen School of Medicine at UCLA, Los Angeles, CA 90095, USA
| | - Akira Ishiyama
- Department of Head and Neck Surgery, David Geffen School of Medicine at UCLA, Los Angeles, CA 90095, USA
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19
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Li P, Qian T, Sun S. Spatial architecture of the cochlear immune microenvironment in noise-induced and age-related sensorineural hearing loss. Int Immunopharmacol 2023; 114:109488. [PMID: 36470117 DOI: 10.1016/j.intimp.2022.109488] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2022] [Revised: 11/16/2022] [Accepted: 11/21/2022] [Indexed: 12/12/2022]
Abstract
The cochlea encodes sound stimuli and transmits them to the central nervous system, and damage to sensory cells and synapses in the cochlea leads to hearing loss. The inner ear was previously considered to be an immune privileged organ to protect the auditory organ from reactions with the immune system. However, recent studies have revealed the presence of resident macrophages in the cochlea, especially in the spiral ligament, spiral ganglion, and stria vascularis. The tissue-resident macrophages are responsible for the detection, phagocytosis, and clearance of cellular debris and pathogens from the tissues, and they initiate inflammation and influence tissue repair by producing inflammatory cytokines and chemokines. Insult to the cochlea can activate the cochlear macrophages to initiate immune responses. In this review, we describe the distribution and functions of cochlear macrophages in noise-induced hearing impairment and age-related hearing disabilities. We also focus on potential therapeutic interventions concerning hearing loss by modulating local immune responses.
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Affiliation(s)
- Peifan Li
- ENT Institute and Otorhinolaryngology, Department of Affiliated Eye and ENT Hospital, Key Laboratory of Hearing Medicine of NHFPC, State Key Laboratory of Medical Neurobiology, Fudan University, Shanghai, 200031, China; Eye and ENT Hospital, Fudan University, Shanghai, 200031, China
| | - Tingting Qian
- ENT Institute and Otorhinolaryngology, Department of Affiliated Eye and ENT Hospital, Key Laboratory of Hearing Medicine of NHFPC, State Key Laboratory of Medical Neurobiology, Fudan University, Shanghai, 200031, China; Eye and ENT Hospital, Fudan University, Shanghai, 200031, China
| | - Shan Sun
- ENT Institute and Otorhinolaryngology, Department of Affiliated Eye and ENT Hospital, Key Laboratory of Hearing Medicine of NHFPC, State Key Laboratory of Medical Neurobiology, Fudan University, Shanghai, 200031, China; Eye and ENT Hospital, Fudan University, Shanghai, 200031, China.
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20
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Zhang N, Li N, Wang S, Xu W, Liu J, Lyu Y, Li X, Song Y, Kong L, Liu Y, Guo J, Fan Z, Zhang D, Wang H. Protective effect of anakinra on audiovestibular function in a murine model of endolymphatic hydrops. Front Cell Neurosci 2022; 16:1088099. [PMID: 36589291 PMCID: PMC9798291 DOI: 10.3389/fncel.2022.1088099] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2022] [Accepted: 11/29/2022] [Indexed: 12/23/2022] Open
Abstract
Introduction Ménière's disease (MD), a common disease in the inner ear, is characterized by an increase in endolymph in the cochlear duct and vestibular labyrinth. The pathophysiology of the condition appears to be the immune response. Studies have shown that basal levels of the IL-1β increased in some MD patients. Methods Here, we used a murine model of endolymphatic hydrops (EH) to study the effect of anakinra on auditory and vestibular function. Mice were intraperitoneal injected with anakinra or saline before LPS by postauricular injection. Weight and disease severity were measured, histologic changes in auditory were assessed, and inflammation state was evaluated. Results We found that anakinra therapy reduced LPS-induced EH, alleviated LPS-induced hearing loss and vestibular dysfunction, and inhibited the expression of the inflammatory cytokines and macrophage infiltration in the cochlea of mice. We further demonstrated that anakinra ameliorated the disorganization and degeneration of myelin sheath, and reduced the neuron damage in cochlea of EH mice. Discussion Consequently, anakinra contributes to a promising therapeutic approach to MD, by restricting EH, alleviating auditory and vestibular function, inhibiting inflammation of the inner ear and protecting the cochlear nerve. Further investigations are needed to assess the potential therapeutic benefits of anakinra in patients with MD.
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Affiliation(s)
- Na Zhang
- Department of Otolaryngology-Head and Neck Surgery, Shandong Provincial ENT Hospital, Shandong University, Jinan, Shandong, China,Shandong Provincial Vertigo and Dizziness Medical Center, Jinan, Shandong, China,Laboratory of Vertigo Disease, Shandong Second Provincial General Hospital, Shandong Institute of Otorhinolaryngology, Jinan, Shandong, China
| | - Na Li
- Department of Otolaryngology-Head and Neck Surgery, Shandong Provincial ENT Hospital, Shandong University, Jinan, Shandong, China,Laboratory of Vertigo Disease, Shandong Second Provincial General Hospital, Shandong Institute of Otorhinolaryngology, Jinan, Shandong, China,Center of Clinical Laboratory, Shandong Second Provincial General Hospital, Jinan, Shandong, China
| | - Siyue Wang
- Department of Otolaryngology-Head and Neck Surgery, Shandong Provincial ENT Hospital, Shandong University, Jinan, Shandong, China,Shandong Provincial Vertigo and Dizziness Medical Center, Jinan, Shandong, China,Laboratory of Vertigo Disease, Shandong Second Provincial General Hospital, Shandong Institute of Otorhinolaryngology, Jinan, Shandong, China
| | - Wandi Xu
- Department of Otolaryngology-Head and Neck Surgery, Shandong Provincial ENT Hospital, Shandong University, Jinan, Shandong, China,Shandong Provincial Vertigo and Dizziness Medical Center, Jinan, Shandong, China,Laboratory of Vertigo Disease, Shandong Second Provincial General Hospital, Shandong Institute of Otorhinolaryngology, Jinan, Shandong, China
| | - Jiahui Liu
- Department of Otolaryngology-Head and Neck Surgery, Shandong Provincial ENT Hospital, Shandong University, Jinan, Shandong, China,Shandong Provincial Vertigo and Dizziness Medical Center, Jinan, Shandong, China,Laboratory of Vertigo Disease, Shandong Second Provincial General Hospital, Shandong Institute of Otorhinolaryngology, Jinan, Shandong, China
| | - Yafeng Lyu
- Department of Otolaryngology-Head and Neck Surgery, Shandong Provincial ENT Hospital, Shandong University, Jinan, Shandong, China,Shandong Provincial Vertigo and Dizziness Medical Center, Jinan, Shandong, China,Laboratory of Vertigo Disease, Shandong Second Provincial General Hospital, Shandong Institute of Otorhinolaryngology, Jinan, Shandong, China
| | - Xiaofei Li
- Department of Otolaryngology-Head and Neck Surgery, Shandong Provincial ENT Hospital, Shandong University, Jinan, Shandong, China,Shandong Provincial Vertigo and Dizziness Medical Center, Jinan, Shandong, China,Laboratory of Vertigo Disease, Shandong Second Provincial General Hospital, Shandong Institute of Otorhinolaryngology, Jinan, Shandong, China
| | - Yongdong Song
- Department of Otolaryngology-Head and Neck Surgery, Shandong Provincial ENT Hospital, Shandong University, Jinan, Shandong, China,Shandong Provincial Vertigo and Dizziness Medical Center, Jinan, Shandong, China,Laboratory of Vertigo Disease, Shandong Second Provincial General Hospital, Shandong Institute of Otorhinolaryngology, Jinan, Shandong, China
| | - Ligang Kong
- Department of Otolaryngology-Head and Neck Surgery, Shandong Provincial ENT Hospital, Shandong University, Jinan, Shandong, China,Shandong Provincial Vertigo and Dizziness Medical Center, Jinan, Shandong, China,Laboratory of Vertigo Disease, Shandong Second Provincial General Hospital, Shandong Institute of Otorhinolaryngology, Jinan, Shandong, China
| | - Yalan Liu
- Department of Otolaryngology-Head and Neck Surgery, Shandong Provincial ENT Hospital, Shandong University, Jinan, Shandong, China,Shandong Provincial Vertigo and Dizziness Medical Center, Jinan, Shandong, China,Laboratory of Vertigo Disease, Shandong Second Provincial General Hospital, Shandong Institute of Otorhinolaryngology, Jinan, Shandong, China
| | - Jia Guo
- Department of Otolaryngology-Head and Neck Surgery, Shandong Provincial ENT Hospital, Shandong University, Jinan, Shandong, China,Shandong Provincial Vertigo and Dizziness Medical Center, Jinan, Shandong, China,Laboratory of Vertigo Disease, Shandong Second Provincial General Hospital, Shandong Institute of Otorhinolaryngology, Jinan, Shandong, China
| | - Zhaomin Fan
- Department of Otolaryngology-Head and Neck Surgery, Shandong Provincial ENT Hospital, Shandong University, Jinan, Shandong, China,Shandong Provincial Vertigo and Dizziness Medical Center, Jinan, Shandong, China,Laboratory of Vertigo Disease, Shandong Second Provincial General Hospital, Shandong Institute of Otorhinolaryngology, Jinan, Shandong, China
| | - Daogong Zhang
- Department of Otolaryngology-Head and Neck Surgery, Shandong Provincial ENT Hospital, Shandong University, Jinan, Shandong, China,Shandong Provincial Vertigo and Dizziness Medical Center, Jinan, Shandong, China,Laboratory of Vertigo Disease, Shandong Second Provincial General Hospital, Shandong Institute of Otorhinolaryngology, Jinan, Shandong, China,*Correspondence: Daogong Zhang,
| | - Haibo Wang
- Department of Otolaryngology-Head and Neck Surgery, Shandong Provincial ENT Hospital, Shandong University, Jinan, Shandong, China,Shandong Provincial Vertigo and Dizziness Medical Center, Jinan, Shandong, China,Laboratory of Vertigo Disease, Shandong Second Provincial General Hospital, Shandong Institute of Otorhinolaryngology, Jinan, Shandong, China,Haibo Wang,
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Jensen MJ, Claussen AD, Higgins T, Vielman-Quevedo R, Mostaert B, Xu L, Kirk J, Hansen MR. Cochlear implant material effects on inflammatory cell function and foreign body response. Hear Res 2022; 426:108597. [PMID: 35963812 PMCID: PMC10875706 DOI: 10.1016/j.heares.2022.108597] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/22/2021] [Revised: 07/08/2022] [Accepted: 08/03/2022] [Indexed: 11/28/2022]
Abstract
OBJECTIVES The objectives of this study were to assess the effects of cochlear implant (CI) biomaterials on the function of macrophages and fibroblasts, two key mediators of the foreign body response (FBR) and to determine how these materials influence fibrous tissue growth and new bone formation within the cochlea. METHODS Macrophages and fibroblasts were cultured on polydimethylsiloxane (PDMS) and platinum substrates and human CI electrodes in vitro. Cell count, cell proliferation, cytokine production, and cell adhesion were measured. CI electrodes were implanted into murine cochleae for three weeks without electrical stimulation. Implanted cochleae were harvested for 3D X-ray microscopy with the CI left in-situ. The location of new bone growth within the scala tympani (ST) with reference to different portions of the implant (PDMS vs platinum) was quantified. RESULTS Cell counts of macrophages and fibroblasts were significantly higher on platinum substrates and platinum contacts of CI electrodes. Fibroblast proliferation was greater on platinum relative to PDMS, and cells grown on platinum formed more/larger focal adhesions. 3D X-ray microscopy showed neo-ossification in the peri‑implant areas of the ST. Volumetric quantification of neo-ossification showed a trend toward greater bone formation adjacent to the platinum electrodes compared to areas opposite or away from the platinum electrode bearing surfaces. CONCLUSIONS Fibrotic reactions are biomaterial specific, as demonstrated by the differences in cell adhesion, proliferation, and fibrosis on platinum and PDMS. The inflammatory reaction to platinum contacts on CI electrodes likely contributes to fibrosis to a greater degree than PDMS, and platinum contacts may influence the deposition of new bone, as demonstrated in the in vivo data. This information can potentially be used to influence the design of future generations of neural prostheses.
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Affiliation(s)
- Megan J Jensen
- Department of Otolaryngology-Head & Neck Surgery, University of Iowa Hospitals and Clinics, Iowa City, IA 52242, United States
| | - Alexander D Claussen
- Department of Otolaryngology-Head & Neck Surgery, University of Iowa Hospitals and Clinics, Iowa City, IA 52242, United States
| | - Timon Higgins
- Carver College of Medicine, Iowa City, IA, United States
| | - Rene Vielman-Quevedo
- Department of Otolaryngology-Head & Neck Surgery, University of Iowa Hospitals and Clinics, Iowa City, IA 52242, United States
| | - Brian Mostaert
- Department of Otolaryngology-Head & Neck Surgery, University of Iowa Hospitals and Clinics, Iowa City, IA 52242, United States
| | - Linjing Xu
- Department of Otolaryngology-Head & Neck Surgery, University of Iowa Hospitals and Clinics, Iowa City, IA 52242, United States
| | | | - Marlan R Hansen
- Department of Otolaryngology-Head & Neck Surgery, University of Iowa Hospitals and Clinics, Iowa City, IA 52242, United States; Department of Neurosurgery, University of Iowa Hospitals and Clinics, Iowa City, IA, United States.
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22
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Song X, Li Y, Guo R, Yu Q, Liu S, Teng Q, Chen ZR, Xie J, Gong S, Liu K. Cochlear resident macrophage mediates development of ribbon synapses via CX3CR1/CX3CL1 axis. Front Mol Neurosci 2022; 15:1031278. [PMID: 36518186 PMCID: PMC9742371 DOI: 10.3389/fnmol.2022.1031278] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2022] [Accepted: 10/31/2022] [Indexed: 08/11/2023] Open
Abstract
Cochlear ribbon synapses formed between spiral ganglion neurons and inner hair cells in postnatal mice must undergo significant morphological and functional development to reach auditory maturation. However, the mechanisms underlying cochlear ribbon synapse remodeling remain unclear. This study found that cochlear resident macrophages are essential for cochlear ribbon synapse development and maturation in mice via the CX3CR1/CX3CL1 axis. CX3CR1 expression (a macrophage surface-specific receptor) and macrophage count in the cochlea were significantly increased from postnatal day 7 then decreased from days 14 to 28. Seven-day treatment with CX3CR1 inhibitors and artificial upregulation of CX3CL1 levels in the inner ear environment using the semicircular canal injection technique were initiated on day 7, and this resulted in a significant increase in hearing threshold on day 28. Additionally, abnormalities in the morphology and number of cochlear ribbon synapses were detected on day P14, which may be associated with hearing impairment. In conclusion, macrophage regulation of cochlear ribbon synapse remodeling via the CX3CR1/CX3CL1 axis is required during hearing development and offers a new perspective on immune-related hearing loss throughout auditory development. Importantly, it could be a new treatment target for sensorineural hearing loss.
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Affiliation(s)
- Xinyu Song
- Department of Otolaryngology Head and Neck Surgery, Beijing Friendship Hospital, Capital Medical University, Beijing, China
- Clinical Center for Hearing Loss, Capital Medical University, Beijing, China
| | - Yang Li
- Department of Otolaryngology Head and Neck Surgery, Beijing Friendship Hospital, Capital Medical University, Beijing, China
- Clinical Center for Hearing Loss, Capital Medical University, Beijing, China
| | - Rui Guo
- Department of Otolaryngology Head and Neck Surgery, Beijing Friendship Hospital, Capital Medical University, Beijing, China
- Clinical Center for Hearing Loss, Capital Medical University, Beijing, China
| | - Qianru Yu
- Department of Otolaryngology Head and Neck Surgery, Beijing Friendship Hospital, Capital Medical University, Beijing, China
- Clinical Center for Hearing Loss, Capital Medical University, Beijing, China
| | - Shan Liu
- Department of Otolaryngology Head and Neck Surgery, Beijing Friendship Hospital, Capital Medical University, Beijing, China
- Clinical Center for Hearing Loss, Capital Medical University, Beijing, China
| | - Qi Teng
- Department of Otolaryngology Head and Neck Surgery, Beijing Friendship Hospital, Capital Medical University, Beijing, China
- Clinical Center for Hearing Loss, Capital Medical University, Beijing, China
| | - Zhong-Rui Chen
- Department of Otolaryngology Head and Neck Surgery, Beijing Friendship Hospital, Capital Medical University, Beijing, China
- Clinical Center for Hearing Loss, Capital Medical University, Beijing, China
| | - Jing Xie
- Department of Otolaryngology Head and Neck Surgery, Beijing Friendship Hospital, Capital Medical University, Beijing, China
- Clinical Center for Hearing Loss, Capital Medical University, Beijing, China
| | - Shusheng Gong
- Department of Otolaryngology Head and Neck Surgery, Beijing Friendship Hospital, Capital Medical University, Beijing, China
- Clinical Center for Hearing Loss, Capital Medical University, Beijing, China
| | - Ke Liu
- Department of Otolaryngology Head and Neck Surgery, Beijing Friendship Hospital, Capital Medical University, Beijing, China
- Clinical Center for Hearing Loss, Capital Medical University, Beijing, China
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23
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Steinacher C, Chacko LJ, Liu W, Rask-Andersen H, Bader W, Dudas J, Sergi CM, Dhanaseelan T, Moreno N, Glueckert R, Hoermann R, Schrott-Fischer A. Visualization of macrophage subsets in the development of the fetal human inner ear. Front Immunol 2022; 13:965196. [PMID: 36159857 PMCID: PMC9501668 DOI: 10.3389/fimmu.2022.965196] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2022] [Accepted: 08/12/2022] [Indexed: 11/13/2022] Open
Abstract
Background Human inner ear contains macrophages whose functional role in early development is yet unclear. Recent studies describe inner ear macrophages act as effector cells of the innate immune system and are often activated following acoustic trauma or exposure to ototoxic drugs. Few or limited literature describing the role of macrophages during inner ear development and organogenesis. Material and Methods We performed a study combining immunohistochemistry and immunofluorescence using antibodies against IBA1, CX3CL1, CD168, CD68, CD45 and CollagenIV. Immune staining and quantification was performed on human embryonic inner ear sections from gestational week 09 to 17. Results The study showed IBA1 and CD45 positive cells in the mesenchymal tissue at GW 09 to GW17. No IBA1 positive macrophages were detected in the sensory epithelium of the cochlea and vestibulum. Fractalkine (CX3CL1) signalling was initiated GW10 and parallel chemotactic attraction and migration of macrophages into the inner ear. Macrophages also migrated into the spiral ganglion, cochlear nerve, and peripheral nerve fibers and tissue-expressing CX3CL1. The mesenchymal tissue at all gestational weeks expressed CD163 and CD68. Conclusion Expressions of markers for resident and non-resident macrophages (IBA1, CD45, CD68, and CD163) were identified in the human fetal inner ear. We speculate that these cells play a role for the development of human inner ear tissue including shaping of the gracile structures.
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Affiliation(s)
- Claudia Steinacher
- Inner Ear Laboratory, Department of Otorhinolaryngology, Medical University of Innsbruck, Innsbruck, Austria
| | - Lejo Johnson Chacko
- Inner Ear Laboratory, Department of Otorhinolaryngology, Medical University of Innsbruck, Innsbruck, Austria
| | - Wei Liu
- Department of Surgical Sciences, Section of Otorhinolaryngology and Head and Neck Surgery, Uppsala University, Uppsala, Sweden
| | - Helge Rask-Andersen
- Department of Surgical Sciences, Section of Otorhinolaryngology and Head and Neck Surgery, Uppsala University, Uppsala, Sweden
| | - Werner Bader
- Inner Ear Laboratory, Department of Otorhinolaryngology, Medical University of Innsbruck, Innsbruck, Austria
| | - Jozsef Dudas
- Inner Ear Laboratory, Department of Otorhinolaryngology, Medical University of Innsbruck, Innsbruck, Austria
| | - Consolato M. Sergi
- Anatomic Pathology Division, Children’s Hospital of Eastern Ontario (CHEO), University of Ottawa, Ottawa, Canada
| | - Tamilvendhan Dhanaseelan
- Biosciences Institute, Faculty of Medical Sciences, Newcastle University, Newcastle upon Tyne, United Kingdom
| | - Nadjeda Moreno
- Developmental Biology and Cancer, University College London (UCL) Great Ormond Street Institute of Child Health, University College London, London, United Kingdom
| | - Rudolf Glueckert
- Inner Ear Laboratory, Department of Otorhinolaryngology, Medical University of Innsbruck, Innsbruck, Austria
| | - Romed Hoermann
- Department of Anatomy, Histology & Embryology, Division of Clinical & Functional Anatomy, Medical University of Innsbruck, Innsbruck, Austria
| | - Anneliese Schrott-Fischer
- Inner Ear Laboratory, Department of Otorhinolaryngology, Medical University of Innsbruck, Innsbruck, Austria
- *Correspondence: Anneliese Schrott-Fischer,
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24
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Keithley EM. Inner ear immunity. Hear Res 2022; 419:108518. [DOI: 10.1016/j.heares.2022.108518] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/22/2021] [Revised: 05/06/2022] [Accepted: 05/10/2022] [Indexed: 11/26/2022]
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25
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Miwa T, Okano T. Role of Inner Ear Macrophages and Autoimmune/Autoinflammatory Mechanisms in the Pathophysiology of Inner Ear Disease. Front Neurol 2022; 13:861992. [PMID: 35463143 PMCID: PMC9019483 DOI: 10.3389/fneur.2022.861992] [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: 01/25/2022] [Accepted: 03/02/2022] [Indexed: 12/02/2022] Open
Abstract
Macrophages play important roles in tissue homeostasis and inflammation. Recent studies have revealed that macrophages are dispersed in the inner ear and may play essential roles in eliciting an immune response. Autoinflammatory diseases comprise a family of immune-mediated diseases, some of which involve sensorineural hearing loss, indicating that similar mechanisms may underlie the pathogenesis of immune-mediated hearing loss. Autoimmune inner ear disease (AIED) is an idiopathic disorder characterized by unexpected hearing loss. Tissue macrophages in the inner ear represent a potential target for modulation of the local immune response in patients with AIED/autoinflammatory diseases. In this review, we describe the relationship between cochlear macrophages and the pathophysiology of AIED/autoinflammatory disease.
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Affiliation(s)
- Toru Miwa
- Department of Otolaryngology-Head and Neck Surgery, Graduate School of Medicine, Kyoto University, Kyoto, Japan
- Department of Otolaryngology-Head and Neck Surgery, Tazuke Kofukai Medical Research Institute Kitano Hospital, Osaka, Japan
- *Correspondence: Toru Miwa
| | - Takayuki Okano
- Department of Otolaryngology-Head and Neck Surgery, Graduate School of Medicine, Kyoto University, Kyoto, Japan
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26
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Seicol BJ, Lin S, Xie R. Age-Related Hearing Loss Is Accompanied by Chronic Inflammation in the Cochlea and the Cochlear Nucleus. Front Aging Neurosci 2022; 14:846804. [PMID: 35418849 PMCID: PMC8995794 DOI: 10.3389/fnagi.2022.846804] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2021] [Accepted: 03/07/2022] [Indexed: 12/24/2022] Open
Abstract
Age-related hearing loss (ARHL) is a major hearing impairment characterized by pathological changes in both the peripheral and central auditory systems. Low-grade inflammation was observed in the cochlea of deceased human subjects with ARHL and animal models of early onset ARHL, which suggests that inflammation contributes to the development of ARHL. However, it remains elusive how chronic inflammation progresses during normal aging in the cochlea, and especially the accompanying changes of neuroinflammation in the central auditory system. To address this, we investigated chronic inflammation in both the cochlea and the cochlear nucleus (CN) of CBA/CaJ mice, an inbred mouse strain that undergoes normal aging and develops human, like-late-onset ARHL. Using immunohistochemistry, confocal microscopy, and quantitative image processing, we measured the accumulation and activation of macrophages in the cochlea and microglia in the CN using their shared markers: ionized calcium binding adaptor molecule 1 (Iba1) and CD68—a marker of phagocytic activity. We found progressive increases in the area covered by Iba1-labeled macrophages and enhanced CD68 staining in the osseous spiral lamina of the cochlea that correlated with elevated ABR threshold across the lifespan. During the process, we further identified significant increases in microglial activation and C1q deposition in the CN, indicating increased neuroinflammation and complement activation in the central auditory system. Our study suggests that during normal aging, chronic inflammation occurs in both the peripheral and the central auditory system, which may contribute in coordination to the development of ARHL.
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Affiliation(s)
- Benjamin J. Seicol
- Department of Otolaryngology—Head and Neck Surgery, The Ohio State University, Columbus, OH, United States
- Department of Neuroscience, The Ohio State University, Columbus, OH, United States
| | - Shengyin Lin
- Department of Otolaryngology—Head and Neck Surgery, The Ohio State University, Columbus, OH, United States
| | - Ruili Xie
- Department of Otolaryngology—Head and Neck Surgery, The Ohio State University, Columbus, OH, United States
- Department of Neuroscience, The Ohio State University, Columbus, OH, United States
- *Correspondence: Ruili Xie
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27
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Vogl C, Neef J, Wichmann C. Methods for multiscale structural and functional analysis of the mammalian cochlea. Mol Cell Neurosci 2022; 120:103720. [DOI: 10.1016/j.mcn.2022.103720] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2021] [Revised: 02/13/2022] [Accepted: 03/08/2022] [Indexed: 01/11/2023] Open
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Ito T, Kurata N, Fukunaga Y. Tissue-Resident Macrophages in the Stria Vascularis. Front Neurol 2022; 13:818395. [PMID: 35185769 PMCID: PMC8850293 DOI: 10.3389/fneur.2022.818395] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2021] [Accepted: 01/13/2022] [Indexed: 12/20/2022] Open
Abstract
Tissue-resident macrophages play an important role in clearance, development, and regulation of metabolism. They also function as sentinel immune cells, initiating inflammatory responses, clearing inflammatory debris, and maintaining homeostatic tissue environment. In the cochlea, the roles of tissue-resident macrophages include maintaining steady-state tissues, immunological defense, and repairing pathological conditions associated with noise, ototoxic drugs, aging, and various pathogens. Perivascular macrophages (PVMs) are a unique subset of tissue-resident macrophages that are closely associated with blood vessels and have unique expression markers in certain tissues. PVMs are found in the inner ear, brain, skin, liver, and retina. The origin of PVMs in the inner ear is unclear, but they are already present during embryonic development. PVMs are members of the blood labyrinth barrier and regulate blood vessel permeability in the stria vascularis, which lies on the lateral wall of the cochlear duct and is crucial for endocochlear potential formation. The cytoplasm of strial PVMs can contain pigment granules that increase in number with age. Strial PVMs are activated by the loss of Slc26a4 in the cochleae, and they subsequently phagocytose aggregated pigment granules and possibly degenerated intermediate cells. This review summarizes the current knowledge of characteristic features and proposed roles of PVMs in the stria vascularis. We also address macrophage activation and involvement of pigment granules with the loss of Slc26a4 in the cochleae.
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29
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Liu W, Danckwardt-Lillieström N, Schrott-Fischer A, Glueckert R, Rask-Andersen H. Distribution of Immune Cells Including Macrophages in the Human Cochlea. Front Neurol 2021; 12:781702. [PMID: 34880828 PMCID: PMC8645652 DOI: 10.3389/fneur.2021.781702] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2021] [Accepted: 10/21/2021] [Indexed: 12/20/2022] Open
Abstract
Background: The human cochlea was earlier believed to lack capacity to mount specific immune responses. Recent studies established that the human cochlea holds macrophages. The cells appear to surveil, dispose of, and restore wasted cells to maintain tissue integrity. Macrophage activities are believed to be the central elements in immune responses and could swiftly defuse invading microbes that enter via adjacent infection-prone areas. This review updates recent human studies in light of the current literature and adds information about chemokine gene expression. Materials and Methods: We analyzed surgically obtained human tissue using immunohistochemistry, confocal microscopy, and multichannel super-resolution structured illumination microscopy. The samples were considered representative of steady-state conditions. Antibodies against the ionized calcium-binding adaptor molecule 1 were used to identify the macrophages. CD68 and CD11b, and the major histocompatibility complex type II (MHCII) and CD4 and CD8 were analyzed. The RNAscope technique was used for fractalkine gene localization. Results: Many macrophages were found around blood vessels in the stria vascularis but not CD4 and CD8 lymphocytes. Amoeboid macrophages were identified in the spiral ganglion with surveilling "antennae" projecting against targeted cells. Synapse-like contacts were seen on spiral ganglion cell bodies richly expressing single CXC3CL gene transcripts. Branching neurite-like processes extended along central and peripheral axons. Active macrophages were occasionally found near degenerating hair cells. Some macrophage-interacting T lymphocytes were observed between the scala tympani wall and Rosenthal's canal. CD4 and CD8 cells were not found in the organ of Corti. Conclusions: The results indicate that the human cochlea is equipped with macrophages and potentially lymphocytes, suggesting both an innate and adaptive immune capacity. A rich expression of fractalkine gene transcripts in spiral ganglion neurons suggest an essential role for auditory nerve protection, as has been demonstrated experimentally. The findings provide further information on the important role of the immune machinery present in the human inner ear and its potential to carry adverse immune reactions, including cytotoxic and foreign body responses. The results can be used to form a rationale for therapies aiming to modulate these immune activities.
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Affiliation(s)
- Wei Liu
- Department of Surgical Sciences, Section of Otorhinolaryngology and Head and Neck Surgery, Uppsala University, Uppsala, Sweden
| | - Niklas Danckwardt-Lillieström
- Department of Surgical Sciences, Section of Otorhinolaryngology and Head and Neck Surgery, Uppsala University, Uppsala, Sweden
| | - Anneliese Schrott-Fischer
- Inner Ear Laboratory, Department of Otorhinolaryngology, Medical University Innsbruck, Innsbruck, Austria
| | - Rudolf Glueckert
- Inner Ear Laboratory, Department of Otorhinolaryngology, Medical University Innsbruck, Innsbruck, Austria
| | - Helge Rask-Andersen
- Department of Surgical Sciences, Section of Otorhinolaryngology and Head and Neck Surgery, Uppsala University, Uppsala, Sweden
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Okayasu T, O’Malley JT, Nadol JB. Prevalence of Macrophages Within the Cochlear Vessels Following Cochlear Implantation in the Human: An Immunohistopathological Study Using Anti-Iba1 Antibody. Otol Neurotol 2021; 42:e1470-e1477. [PMID: 34325451 PMCID: PMC8595581 DOI: 10.1097/mao.0000000000003312] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
HYPOTHESIS The prevalence of monocyte-derived macrophages within cochlear vessels may increase following cochlear implantation. BACKGROUND Recently, we reported an increase in the number of ionized calcium-binding adaptor molecule 1 (Iba1)-positive macrophages in selected cochlear sites such as the osseous spiral lamina and Rosenthal's canal following cochlear implantation. Activation of the immune system induces the recruitment of monocyte-derived macrophages. The prevalence of monocyte-derived macrophages within cochlear vessels may increase following cochlear implantation. However, the delivery system of macrophages to the human cochlea is incompletely understood. METHODS The prevalence of macrophages and monocytes within cochlear blood vessels in 10 human subjects who had undergone unilateral cochlear implantation was studied by light microscopy using anti-Iba1 immunostaining. The densities of Iba1-positve monocytes per area of lumen of cochlear vessels in the sections near the round window in implanted ears were compared with the contralateral unimplanted ears. The correlation between the densities of Iba1-positve monocytes and the duration (months after the cochlear implantation) was also evaluated. RESULTS The prevalence of Iba1-positive macrophages/monocytes in vessels near the round window in implanted ears (mean 26%, median 21%) was greater than in opposite unimplanted ears (mean 5.2%, median 2.5%: p < 0.01). The density of Iba1-positive monocytes in implanted ears (mean 32, median 16 cells/105 μm2) tended to be greater than that in unimplanted ears (mean 6.6, median 0.93 cells/105 μm2: p = 0.08). The density of Iba1-positive monocytes was significantly correlated with duration of implantation but not in the unimplanted ears. CONCLUSION An increase in prevalence of Iba1-positive macrophages/monocytes within cochlear blood vessels after cochlear implantation was demonstrated. These findings suggest a delivery system of Iba1-positive macrophages through cochlear vessels in human that is ongoing for long duration.
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Affiliation(s)
- Tadao Okayasu
- Otopathology Laboratory, Department of Otolaryngology-Head and Neck Surgery, Massachusetts Eye and Ear, 243 Charles Street, Boston, MA 02114 USA
- Department of Otolaryngology, Harvard Medical School-Head and Neck Surgery, 243 Charles Street, Boston, MA 02114 USA
- Department of Otolaryngology-Head and Neck Surgery, Nara Medical University, 840 Shijo-cho, Kashihara city, Nara 634-8522, Japan
| | - Jennifer T. O’Malley
- Otopathology Laboratory, Department of Otolaryngology-Head and Neck Surgery, Massachusetts Eye and Ear, 243 Charles Street, Boston, MA 02114 USA
| | - Joseph B. Nadol
- Otopathology Laboratory, Department of Otolaryngology-Head and Neck Surgery, Massachusetts Eye and Ear, 243 Charles Street, Boston, MA 02114 USA
- Department of Otolaryngology, Harvard Medical School-Head and Neck Surgery, 243 Charles Street, Boston, MA 02114 USA
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Quan Q, Hong L, Wang Y, Li R, Yin X, Cheng X, Liu G, Tang H, Meng H, Liu S, Guo Q, Lai B, Zhao Q, Wei M, Peng J, Tang P. Hybrid material mimics a hypoxic environment to promote regeneration of peripheral nerves. Biomaterials 2021; 277:121068. [PMID: 34419733 DOI: 10.1016/j.biomaterials.2021.121068] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/01/2021] [Revised: 07/29/2021] [Accepted: 08/08/2021] [Indexed: 12/17/2022]
Abstract
Between nerve defects, a bridge formed by multiple cells is the fundamental structure for guiding axons across this damaged region. Here, we developed a functional material that mimics hypoxia during the early stages of nerve regeneration by deferoxamine. We used this material and single-cell sequencing to analyze the "bridge" structure between peripheral nerve defects. We found that hypoxia in damaged tissues might play a key role in stimulating macrophages, promoting endothelial-to-mesenchymal transition, and driving the migration of endothelial cells to the injured region to form regenerative bridge tissue and guide the subsequent regeneration of Schwann cells and axons. The results showed that the final nerve defect repair outcomes were similar with autografts after intervention by this material. This study challenges the view that hypoxia is exclusively involved in peripheral nerve regeneration and provides a potentially valuable candidate material for clinical use.
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Affiliation(s)
- Qi Quan
- Department of Orthopedic Surgery, Key Laboratory of Musculoskeletal Trauma &War Injuries PLA, Beijing Key Lab of Regenerative Medicine in Orthopedics, The 4th Medical Centre, Chinese PLA General Hospital, Beijing, China.
| | - Lei Hong
- Department of Orthopedic Surgery, Key Laboratory of Musculoskeletal Trauma &War Injuries PLA, Beijing Key Lab of Regenerative Medicine in Orthopedics, The 4th Medical Centre, Chinese PLA General Hospital, Beijing, China
| | - Yu Wang
- Department of Orthopedic Surgery, Key Laboratory of Musculoskeletal Trauma &War Injuries PLA, Beijing Key Lab of Regenerative Medicine in Orthopedics, The 4th Medical Centre, Chinese PLA General Hospital, Beijing, China; The Neural Regeneration Co-Innovation Center of Jiangsu Province, Nantong, China
| | - Rui Li
- Department of Orthopedic Surgery, Key Laboratory of Musculoskeletal Trauma &War Injuries PLA, Beijing Key Lab of Regenerative Medicine in Orthopedics, The 4th Medical Centre, Chinese PLA General Hospital, Beijing, China
| | - Xin Yin
- Department of Orthopedic Surgery, Key Laboratory of Musculoskeletal Trauma &War Injuries PLA, Beijing Key Lab of Regenerative Medicine in Orthopedics, The 4th Medical Centre, Chinese PLA General Hospital, Beijing, China
| | - Xiaoqing Cheng
- Department of Orthopedic Surgery, Key Laboratory of Musculoskeletal Trauma &War Injuries PLA, Beijing Key Lab of Regenerative Medicine in Orthopedics, The 4th Medical Centre, Chinese PLA General Hospital, Beijing, China
| | - Guangbo Liu
- Department of Orthopedic Surgery, PLA Strategic Support Force Characteristic Medical Center, China
| | - He Tang
- Beijing Anzhen Hospital, Capital Medical University, Key Laboratory of Remodeling-Related Cardiovascular Diseases, Ministry of Education, Beijing Collaborative Innovation Center for Cardiovascular Disorders, China
| | - Haoye Meng
- Department of Orthopedic Surgery, Key Laboratory of Musculoskeletal Trauma &War Injuries PLA, Beijing Key Lab of Regenerative Medicine in Orthopedics, The 4th Medical Centre, Chinese PLA General Hospital, Beijing, China
| | - Shuyun Liu
- Department of Orthopedic Surgery, Key Laboratory of Musculoskeletal Trauma &War Injuries PLA, Beijing Key Lab of Regenerative Medicine in Orthopedics, The 4th Medical Centre, Chinese PLA General Hospital, Beijing, China
| | - Quanyi Guo
- Department of Orthopedic Surgery, Key Laboratory of Musculoskeletal Trauma &War Injuries PLA, Beijing Key Lab of Regenerative Medicine in Orthopedics, The 4th Medical Centre, Chinese PLA General Hospital, Beijing, China
| | - Biqin Lai
- Key Laboratory for Stem Cells and Tissue Engineering, Sun Yat-sen University, Ministry of Education, Guangzhou, China
| | - Qing Zhao
- Department of Orthopedic Surgery, Key Laboratory of Musculoskeletal Trauma &War Injuries PLA, Beijing Key Lab of Regenerative Medicine in Orthopedics, The 4th Medical Centre, Chinese PLA General Hospital, Beijing, China
| | - Min Wei
- Department of Orthopedic Surgery, Key Laboratory of Musculoskeletal Trauma &War Injuries PLA, Beijing Key Lab of Regenerative Medicine in Orthopedics, The 4th Medical Centre, Chinese PLA General Hospital, Beijing, China.
| | - Jiang Peng
- Department of Orthopedic Surgery, Key Laboratory of Musculoskeletal Trauma &War Injuries PLA, Beijing Key Lab of Regenerative Medicine in Orthopedics, The 4th Medical Centre, Chinese PLA General Hospital, Beijing, China; The Neural Regeneration Co-Innovation Center of Jiangsu Province, Nantong, China.
| | - Peifu Tang
- Department of Orthopedic Surgery, Key Laboratory of Musculoskeletal Trauma &War Injuries PLA, Beijing Key Lab of Regenerative Medicine in Orthopedics, The 4th Medical Centre, Chinese PLA General Hospital, Beijing, China.
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32
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Stothert AR, Kaur T. Innate Immunity to Spiral Ganglion Neuron Loss: A Neuroprotective Role of Fractalkine Signaling in Injured Cochlea. Front Cell Neurosci 2021; 15:694292. [PMID: 34408629 PMCID: PMC8365835 DOI: 10.3389/fncel.2021.694292] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2021] [Accepted: 07/14/2021] [Indexed: 12/20/2022] Open
Abstract
Immune system dysregulation is increasingly being attributed to the development of a multitude of neurodegenerative diseases. This, in large part, is due to the delicate relationship that exists between neurons in the central nervous system (CNS) and peripheral nervous system (PNS), and the resident immune cells that aid in homeostasis and immune surveillance within a tissue. Classically, the inner ear was thought to be immune privileged due to the presence of a blood-labyrinth barrier. However, it is now well-established that both vestibular and auditory end organs in the inner ear contain a resident (local) population of macrophages which are the phagocytic cells of the innate-immune system. Upon cochlear sterile injury or infection, there is robust activation of these resident macrophages and a predominant increase in the numbers of macrophages as well as other types of leukocytes. Despite this, the source, nature, fate, and functions of these immune cells during cochlear physiology and pathology remains unclear. Migration of local macrophages and infiltration of bone-marrow-derived peripheral blood macrophages into the damaged cochlea occur through various signaling cascades, mediated by the release of specific chemical signals from damaged sensory and non-sensory cells of the cochlea. One such signaling pathway is CX3CL1-CX3CR1, or fractalkine (FKN) signaling, a direct line of communication between macrophages and sensory inner hair cells (IHCs) and spiral ganglion neurons (SGNs) of the cochlea. Despite the known importance of this neuron-immune axis in CNS function and pathology, until recently it was not clear whether this signaling axis played a role in macrophage chemotaxis and SGN survival following cochlear injury. In this review, we will explore the importance of innate immunity in neurodegenerative disease development, specifically focusing on the regulation of the CX3CL1-CX3CR1 axis, and present evidence for a role of FKN signaling in cochlear neuroprotection.
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Affiliation(s)
- Andrew Rigel Stothert
- Department of Biomedical Sciences, School of Medicine, Creighton University, Omaha, NE, United States
| | - Tejbeer Kaur
- Department of Biomedical Sciences, School of Medicine, Creighton University, Omaha, NE, United States
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Wu L, Vasilijic S, Sun Y, Chen J, Landegger LD, Zhang Y, Zhou W, Ren J, Early S, Yin Z, Ho WW, Zhang N, Gao X, Lee GY, Datta M, Sagers JE, Brown A, Muzikansky A, Stemmer-Rachamimov A, Zhang L, Plotkin SR, Jain RK, Stankovic KM, Xu L. Losartan prevents tumor-induced hearing loss and augments radiation efficacy in NF2 schwannoma rodent models. Sci Transl Med 2021; 13:eabd4816. [PMID: 34261799 PMCID: PMC8409338 DOI: 10.1126/scitranslmed.abd4816] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2020] [Revised: 12/10/2020] [Accepted: 05/20/2021] [Indexed: 12/14/2022]
Abstract
Hearing loss is one of the most common symptoms of neurofibromatosis type 2 (NF2) caused by vestibular schwannomas (VSs). Fibrosis in the VS tumor microenvironment (TME) is associated with hearing loss in patients with NF2. We hypothesized that reducing the fibrosis using losartan, an FDA-approved antihypertensive drug that blocks fibrotic and inflammatory signaling, could improve hearing. Using NF2 mouse models, we found that losartan treatment normalized the TME by (i) reducing neuroinflammatory IL-6/STAT3 signaling and preventing hearing loss, (ii) normalizing tumor vasculature and alleviating neuro-edema, and (iii) increasing oxygen delivery and enhancing efficacy of radiation therapy. In preparation to translate these exciting findings into the clinic, we used patient samples and data and demonstrated that IL-6/STAT3 signaling inversely associated with hearing function, that elevated production of tumor-derived IL-6 was associated with reduced viability of cochlear sensory cells and neurons in ex vivo organotypic cochlear cultures, and that patients receiving angiotensin receptor blockers have no progression in VS-induced hearing loss compared with patients on other or no antihypertensives based on a retrospective analysis of patients with VS and hypertension. Our study provides the rationale and critical data for a prospective clinical trial of losartan in patients with VS.
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Affiliation(s)
- Limeng Wu
- Edwin L. Steele Laboratories, Department of Radiation Oncology, Massachusetts General Hospital and Harvard Medical School, Boston, MA 02114, USA
| | - Sasa Vasilijic
- Eaton-Peabody Laboratories and Department of Otolaryngology, Head and Neck Surgery, Massachusetts Eye and Ear and Harvard Medical School, Boston, MA 02114, USA
| | - Yao Sun
- Edwin L. Steele Laboratories, Department of Radiation Oncology, Massachusetts General Hospital and Harvard Medical School, Boston, MA 02114, USA
| | - Jie Chen
- Edwin L. Steele Laboratories, Department of Radiation Oncology, Massachusetts General Hospital and Harvard Medical School, Boston, MA 02114, USA
| | - Lukas D Landegger
- Eaton-Peabody Laboratories and Department of Otolaryngology, Head and Neck Surgery, Massachusetts Eye and Ear and Harvard Medical School, Boston, MA 02114, USA
| | - Yanling Zhang
- Edwin L. Steele Laboratories, Department of Radiation Oncology, Massachusetts General Hospital and Harvard Medical School, Boston, MA 02114, USA
| | - Wenjianlong Zhou
- Edwin L. Steele Laboratories, Department of Radiation Oncology, Massachusetts General Hospital and Harvard Medical School, Boston, MA 02114, USA
| | - Jun Ren
- Edwin L. Steele Laboratories, Department of Radiation Oncology, Massachusetts General Hospital and Harvard Medical School, Boston, MA 02114, USA
| | - Samuel Early
- Eaton-Peabody Laboratories and Department of Otolaryngology, Head and Neck Surgery, Massachusetts Eye and Ear and Harvard Medical School, Boston, MA 02114, USA
- Division of Otolaryngology, Head and Neck Surgery, Department of Surgery, UC San Diego Medical Center, San Diego, CA 92103, USA
| | - Zhenzhen Yin
- Edwin L. Steele Laboratories, Department of Radiation Oncology, Massachusetts General Hospital and Harvard Medical School, Boston, MA 02114, USA
| | - William W Ho
- Edwin L. Steele Laboratories, Department of Radiation Oncology, Massachusetts General Hospital and Harvard Medical School, Boston, MA 02114, USA
| | - Na Zhang
- Edwin L. Steele Laboratories, Department of Radiation Oncology, Massachusetts General Hospital and Harvard Medical School, Boston, MA 02114, USA
- Department of Otolaryngology, Head and Neck Surgery, Beijing TongRen Hospital, Capital Medical University, Beijing 100730, China
| | - Xing Gao
- Edwin L. Steele Laboratories, Department of Radiation Oncology, Massachusetts General Hospital and Harvard Medical School, Boston, MA 02114, USA
| | - Grace Y Lee
- St. Mark's School, Southborough, MA 01772, USA
| | - Meenal Datta
- Edwin L. Steele Laboratories, Department of Radiation Oncology, Massachusetts General Hospital and Harvard Medical School, Boston, MA 02114, USA
| | - Jessica E Sagers
- Eaton-Peabody Laboratories and Department of Otolaryngology, Head and Neck Surgery, Massachusetts Eye and Ear and Harvard Medical School, Boston, MA 02114, USA
| | - Alyssa Brown
- Eaton-Peabody Laboratories and Department of Otolaryngology, Head and Neck Surgery, Massachusetts Eye and Ear and Harvard Medical School, Boston, MA 02114, USA
| | - Alona Muzikansky
- Division of Biostatistics, Massachusetts General Hospital, Harvard Medical School, Boston, MA 02114, USA
| | | | - Luo Zhang
- Department of Otolaryngology, Head and Neck Surgery, Beijing TongRen Hospital, Capital Medical University, Beijing 100730, China
| | - Scott R Plotkin
- Department of Neurology and Cancer Center, Massachusetts General Hospital, Boston, MA 02114, USA
| | - Rakesh K Jain
- Edwin L. Steele Laboratories, Department of Radiation Oncology, Massachusetts General Hospital and Harvard Medical School, Boston, MA 02114, USA
| | - Konstantina M Stankovic
- Eaton-Peabody Laboratories and Department of Otolaryngology, Head and Neck Surgery, Massachusetts Eye and Ear and Harvard Medical School, Boston, MA 02114, USA.
| | - Lei Xu
- Edwin L. Steele Laboratories, Department of Radiation Oncology, Massachusetts General Hospital and Harvard Medical School, Boston, MA 02114, USA.
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34
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Zhang X, Wang LP, Ziober A, Zhang PJ, Bagg A. Ionized Calcium Binding Adaptor Molecule 1 (IBA1). Am J Clin Pathol 2021; 156:86-99. [PMID: 33582751 DOI: 10.1093/ajcp/aqaa209] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
OBJECTIVES Ionized calcium binding adaptor molecule 1 (IBA1), a marker of microglia/macrophages, has not been investigated in human hematopathologic contexts. We evaluated its expression in mature and immature neoplasms of monocytic/histiocytic and dendritic cell (DC) origin. METHODS Immunohistochemistry for IBA1, CD14, CD68, and CD163 was performed on a total of 114 cases, including a spectrum of monocytic/histiocytic and DC neoplasms (20 tissue based and 59 bone marrow based) and several nonhistiocytic/monocytic/DC neoplasms as control groups (15 tissue based and 20 bone marrow based). RESULTS IBA1 expression was observed in all types of mature tissue-based histiocytic/DC neoplasms (20/20) but not in the corresponding control group (0/15). In bone marrow-based cases, IBA1 was expressed in most acute myeloid leukemias (AMLs) with monocytic differentiation (48/53), both blastic plasmacytoid dendritic cell neoplasms (2/2), and all chronic myelomonocytic leukemias (4/4), while it was positive in only one nonmonocytic AML (1/15) and none of the acute lymphoblastic leukemias (0/5). Collectively, IBA1 showed much higher sensitivity and specificity (93.7%, 97.1%) compared with CD14 (65.4%, 88.2%), CD68 (74.4%, 74.2%), and CD163 (52.6%, 90.6%). CONCLUSIONS IBA1 is a novel, highly sensitive, and specific marker for diagnosing neoplasms of monocytic/histiocytic and DC origin.
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Affiliation(s)
- Xiaoming Zhang
- Department of Pathology and Laboratory Medicine, Hospital of the University of Pennsylvania, Philadelphia
| | - Li-Ping Wang
- Department of Pathology and Laboratory Medicine, Hospital of the University of Pennsylvania, Philadelphia
| | - Amy Ziober
- Department of Pathology and Laboratory Medicine, Hospital of the University of Pennsylvania, Philadelphia
| | - Paul J Zhang
- Department of Pathology and Laboratory Medicine, Hospital of the University of Pennsylvania, Philadelphia
| | - Adam Bagg
- Department of Pathology and Laboratory Medicine, Hospital of the University of Pennsylvania, Philadelphia
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The Distribution and Prevalence of Macrophages in the Cochlea Following Cochlear Implantation in the Human: An Immunohistochemical Study Using Anti-Iba1 Antibody. Otol Neurotol 2021; 41:e304-e316. [PMID: 31821256 DOI: 10.1097/mao.0000000000002495] [Citation(s) in RCA: 24] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
HYPOTHESIS Cochlear implantation may cause an increase in the number of macrophages in the human cochlea similar to previous findings in the vestibular endorgans. BACKGROUND Macrophages play a key role in both an inflammatory response and homeostatic maintenance. Recently, an increase in the prevalence of macrophages was demonstrated in the human vestibular endorgans after implantation. However, the prevalence of macrophages in the cochlea after implantation is unclear. The aim of this study was to compare the distribution and prevalence of macrophages in implanted human cochleae and the contralateral unimplanted ears. METHODS The prevalence of macrophages in the cochlea in 10 human subjects who had undergone unilateral cochlear implantation was studied by light microscopy using anti-Iba1 immunostaining. The densities of macrophages in the osseous spiral lamina (OSL) and Rosenthal's canal (RC) in implanted cochleae were compared with the contralateral unimplanted ears. The distribution of macrophage morphology (amoeboid, transitional, and ramified) was also compared. RESULTS There were activated and phagocytosing macrophages within the fibrotic sheath surrounding the electrode track and within fibrous tissue with lymphocytic infiltration in implanted ears. The densities of macrophages in OSL and RC in implanted ears were significantly greater than in unimplanted ears in some areas. There was also a difference in the prevalence of macrophage phenotype between the OSL and RC. CONCLUSION An increase in the density of macrophages in the cochlea after cochlear implantation was demonstrated. Both phagocytosis and anti-inflammatory activity of macrophages were suggested by the distribution and prevalence of macrophages in the implanted cochlea.
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Liu W, Luque M, Li H, Schrott-Fischer A, Glueckert R, Tylstedt S, Rajan G, Ladak H, Agrawal S, Rask-Andersen H. Spike Generators and Cell Signaling in the Human Auditory Nerve: An Ultrastructural, Super-Resolution, and Gene Hybridization Study. Front Cell Neurosci 2021; 15:642211. [PMID: 33796009 PMCID: PMC8008129 DOI: 10.3389/fncel.2021.642211] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2020] [Accepted: 02/22/2021] [Indexed: 11/23/2022] Open
Abstract
Background: The human auditory nerve contains 30,000 nerve fibers (NFs) that relay complex speech information to the brain with spectacular acuity. How speech is coded and influenced by various conditions is not known. It is also uncertain whether human nerve signaling involves exclusive proteins and gene manifestations compared with that of other species. Such information is difficult to determine due to the vulnerable, "esoteric," and encapsulated human ear surrounded by the hardest bone in the body. We collected human inner ear material for nanoscale visualization combining transmission electron microscopy (TEM), super-resolution structured illumination microscopy (SR-SIM), and RNA-scope analysis for the first time. Our aim was to gain information about the molecular instruments in human auditory nerve processing and deviations, and ways to perform electric modeling of prosthetic devices. Material and Methods: Human tissue was collected during trans-cochlear procedures to remove petro-clival meningioma after ethical permission. Cochlear neurons were processed for electron microscopy, confocal microscopy (CM), SR-SIM, and high-sensitive in situ hybridization for labeling single mRNA transcripts to detect ion channel and transporter proteins associated with nerve signal initiation and conductance. Results: Transport proteins and RNA transcripts were localized at the subcellular level. Hemi-nodal proteins were identified beneath the inner hair cells (IHCs). Voltage-gated ion channels (VGICs) were expressed in the spiral ganglion (SG) and axonal initial segments (AISs). Nodes of Ranvier (NR) expressed Nav1.6 proteins, and encoding genes critical for inter-cellular coupling were disclosed. Discussion: Our results suggest that initial spike generators are located beneath the IHCs in humans. The first NRs appear at different places. Additional spike generators and transcellular communication may boost, sharpen, and synchronize afferent signals by cell clusters at different frequency bands. These instruments may be essential for the filtering of complex sounds and may be challenged by various pathological conditions.
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Affiliation(s)
- Wei Liu
- Section of Otolaryngology, Department of Surgical Sciences, Head and Neck Surgery, Uppsala University Hospital, Uppsala, Sweden
| | - Maria Luque
- Department of Otorhinolaryngology, Medical University of Innsbruck, Innsbruck, Austria
| | - Hao Li
- Section of Otolaryngology, Department of Surgical Sciences, Head and Neck Surgery, Uppsala University Hospital, Uppsala, Sweden
| | | | - Rudolf Glueckert
- Department of Otorhinolaryngology, Medical University of Innsbruck, Innsbruck, Austria
| | - Sven Tylstedt
- Department of Olaryngology, Västerviks Hospital, Västervik, Sweden
| | - Gunesh Rajan
- Department of Otolaryngology, Head & Neck Surgery, Luzerner Kantonsspital, Luzern, Switzerland
- Department of Otolaryngology, Head & Neck Surgery, Division of Surgery, Medical School, University of Western Australia, Perth, WA, Australia
| | - Hanif Ladak
- Department of Otolaryngology-Head and Neck Surgery, Department of Medical Biophysics and Department of Electrical and Computer Engineering, Western University, London, ON, Canada
| | - Sumit Agrawal
- Department of Otolaryngology-Head and Neck Surgery, Western University, London, ON, Canada
| | - Helge Rask-Andersen
- Section of Otolaryngology, Department of Surgical Sciences, Head and Neck Surgery, Uppsala University Hospital, Uppsala, Sweden
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Outcome of Cochlear Implantation in NLRP3-related Autoinflammatory Inner Ear Disorders. Otol Neurotol 2021; 42:e168-e171. [PMID: 33156237 DOI: 10.1097/mao.0000000000002933] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
OBJECTIVE Hearing loss is a highly penetrant phenotype in NLRP3 (Nod-Like-Receptor-Pyrin containing 3) gene-related autoinflammatory disorders. A recent study revealed potential medical treatment of hearing loss with anakinra (anti-interleukin 1 receptor antagonist) in selected cases. However, for severely aggravated hearing loss not responsive to anakinra, cochlear implantation (CI) would be the last resort for hearing rehabilitation. Outcome of CI is not clearly elucidated yet in this emerging type of hearing loss related to NLRP3-related autoinflammatory disorders, which has a systemic nature and ubiquitous distribution of resident macrophages involving the spiral ganglion neuron and the cochlear nerve. Here, we report the successful outcome of CI in NLRP3-related autoinflammatory disorder. PATIENTS Three subjects representing each type of NLRP3-related autoinflammatory disorder: chronic infantile, neurological, cutaneous, and articular syndrome; Muckle-Wells syndrome; and DFNA34, who underwent CI for auditory rehabilitation, were recruited. INTERVENTIONS Phenotypes as well as genotypes were reviewed in the subjects. MAIN OUTCOME MEASURES Audiologic performances before/after CI over time were evaluated. RESULTS All three subjects showed excellent audiological outcomes with rapid improvement of speech perception test result reaching plateau at 3 months after CI, although distribution of the disease predicted poor outcome based on theoretical analysis. CONCLUSIONS This is the first report to present outcome of CI among subjects with a confirmed NLRP3 genetic etiology and resultant systemic inflammation, and suggests that CI is a viable treatment option in this disease entity.
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Baumgartner JE, Baumgartner LS, Baumgartner ME, Moore EJ, Messina SA, Seidman MD, Shook DR. Progenitor cell therapy for acquired pediatric nervous system injury: Traumatic brain injury and acquired sensorineural hearing loss. Stem Cells Transl Med 2021; 10:164-180. [PMID: 33034162 PMCID: PMC7848325 DOI: 10.1002/sctm.20-0026] [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: 01/22/2020] [Revised: 08/18/2020] [Accepted: 08/24/2020] [Indexed: 12/16/2022] Open
Abstract
While cell therapies hold remarkable promise for replacing injured cells and repairing damaged tissues, cell replacement is not the only means by which these therapies can achieve therapeutic effect. For example, recent publications show that treatment with varieties of adult, multipotent stem cells can improve outcomes in patients with neurological conditions such as traumatic brain injury and hearing loss without directly replacing damaged or lost cells. As the immune system plays a central role in injury response and tissue repair, we here suggest that multipotent stem cell therapies achieve therapeutic effect by altering the immune response to injury, thereby limiting damage due to inflammation and possibly promoting repair. These findings argue for a broader understanding of the mechanisms by which cell therapies can benefit patients.
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Affiliation(s)
- James E. Baumgartner
- Advent Health for ChildrenOrlandoFloridaUSA
- Department of Neurological SurgeryUniversity of Central Florida College of MedicineOrlandoFloridaUSA
| | | | | | - Ernest J. Moore
- Department of Audiology and Speech Language PathologyUniversity of North TexasDentonTexasUSA
| | | | - Michael D. Seidman
- Advent Health CelebrationCelebrationFloridaUSA
- Department of OtorhinolaryngologyUniversity of Central FloridaOrlandoFloridaUSA
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Abstract
Emotional stress has accompanied humans since the dawn of time and has played an essential role not only in positive selection and adaptation to an ever-changing environment, but also in the acceleration or even initiation of many illnesses. The three main somatic mechanisms induced by stress are the hypothalamus-pituitary-adrenal axis (HPA axis), the sympathetic-adreno-medullar (SAM) axis, and the immune axis. In this chapter, the stress-induced mechanisms that can affect cochlear physiology are presented and discussed in the context of tinnitus generation and auditory neurobiology. It is concluded that all of the presented mechanisms need to be further investigated. It is advised that clinical practitioners ask patients about stressful events or chronic stress preceding the tinnitus onset and measure the vital signs. Finally, taking into account that tinnitus itself acts as a stressor, the implementation of anti-stress therapies for tinnitus treatment is recommended.
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40
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Rai V, Wood MB, Feng H, Schabla NM, Tu S, Zuo J. The immune response after noise damage in the cochlea is characterized by a heterogeneous mix of adaptive and innate immune cells. Sci Rep 2020; 10:15167. [PMID: 32938973 PMCID: PMC7495466 DOI: 10.1038/s41598-020-72181-6] [Citation(s) in RCA: 37] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2020] [Accepted: 08/24/2020] [Indexed: 02/08/2023] Open
Abstract
Cells of the immune system are present in the adult cochlea and respond to damage caused by noise exposure. However, the types of immune cells involved and their locations within the cochlea are unclear. We used flow cytometry and immunostaining to reveal the heterogeneity of the immune cells in the cochlea and validated the presence of immune cell gene expression by analyzing existing single-cell RNA-sequencing (scRNAseq) data. We demonstrate that cell types of both the innate and adaptive immune system are present in the cochlea. In response to noise damage, immune cells increase in number. B, T, NK, and myeloid cells (macrophages and neutrophils) are the predominant immune cells present. Interestingly, immune cells appear to respond to noise damage by infiltrating the organ of Corti. Our studies highlight the need to further understand the role of these immune cells within the cochlea after noise exposure.
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MESH Headings
- Adaptive Immunity
- Animals
- B-Lymphocytes/immunology
- B-Lymphocytes/pathology
- Cochlea/immunology
- Cochlea/injuries
- Cochlea/pathology
- Disease Models, Animal
- Evoked Potentials, Auditory, Brain Stem/immunology
- Female
- Hearing Loss, Noise-Induced/immunology
- Hearing Loss, Noise-Induced/pathology
- Hearing Loss, Noise-Induced/physiopathology
- Immunity, Innate
- Killer Cells, Natural/immunology
- Killer Cells, Natural/pathology
- Leukocyte Common Antigens/metabolism
- Macrophages/immunology
- Macrophages/pathology
- Male
- Mice
- Mice, 129 Strain
- Mice, Inbred C57BL
- Mice, Transgenic
- Neutrophils/immunology
- Neutrophils/pathology
- Organ of Corti/immunology
- Organ of Corti/injuries
- Organ of Corti/pathology
- RNA-Seq
- T-Lymphocytes/immunology
- T-Lymphocytes/pathology
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Affiliation(s)
- Vikrant Rai
- Department of Biomedical Science, Creighton University School of Medicine, 2500 California Plaza, Omaha, NE, 68178, USA
| | - Megan B Wood
- Department of Otolaryngology-Head and Neck Surgery, Johns Hopkins University School of Medicine, 733 N Broadway, Baltimore, MD, 21205, USA
- Department of Developmental Neurobiology, St. Jude Children's Research Hospital, Memphis, TN, 38105, USA
| | - Hao Feng
- Department of Biomedical Science, Creighton University School of Medicine, 2500 California Plaza, Omaha, NE, 68178, USA
| | - Nathan M Schabla
- Department of Medical Microbiology and Immunology and Flow Cytometry Core, Creighton University School of Medicine, 2500 California Plaza, Omaha, NE, 68178, USA
| | - Shu Tu
- Department of Biomedical Science, Creighton University School of Medicine, 2500 California Plaza, Omaha, NE, 68178, USA
| | - Jian Zuo
- Department of Biomedical Science, Creighton University School of Medicine, 2500 California Plaza, Omaha, NE, 68178, USA.
- Department of Developmental Neurobiology, St. Jude Children's Research Hospital, Memphis, TN, 38105, USA.
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41
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Density of Macrophages Immunostained With Anti-iba1 Antibody in the Vestibular Endorgans After Cochlear Implantation in the Human. Otol Neurotol 2020; 40:e774-e781. [PMID: 31335797 DOI: 10.1097/mao.0000000000002313] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
HYPOTHESIS Cochlear implantation may result in an increase in the density of macrophages in vestibular endorgans in the human. BACKGROUND Vestibular symptoms are a common complication of cochlear implantation. In a previous study, we demonstrated histological evidence of a foreign-body response caused by silicon and platinum in the human cochlea following cochlear implantation. The objective of the current study was to seek evidence of a possible immune response in vestibular endorgans after cochlear implantation. METHODS The density of macrophages immunostained with anti-Iba1 antibody in the vestibular endorgans (lateral and posterior semicircular canals, utricle and saccule) in 10 human subjects who had undergone unilateral cochlear implantation was studied by light microscopy. The densities of macrophages in the neuroepithelium, subepithelial stroma, and among dendritic processes in the mid-stromal zone in four vestibular endorgans in the implanted and the opposite unimplanted ears were compared. The distributions of macrophage morphology (amoeboid, transitional and ramified) were also compared. RESULTS The densities of macrophages in implanted ears in four vestibular endorgans were significantly greater than that in opposite unimplanted ears except in the subepithelial zone of the utricle and posterior semicircular canal. In contrast to the neuroepithelium, the subepithelial distribution of amoeboid macrophages in implanted ears was significantly less than in unimplanted ears. CONCLUSION An increase in the density of macrophages in four vestibular endorgans after implantation was demonstrated. The transition among phenotype of macrophages suggested possible migration of amoeboid macrophages from the subepithelial stroma into the neuroepithelium.
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42
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Hayashi Y, Suzuki H, Nakajima W, Uehara I, Tanimura A, Himeda T, Koike S, Katsuno T, Kitajiri SI, Koyanagi N, Kawaguchi Y, Onomoto K, Kato H, Yoneyama M, Fujita T, Tanaka N. Cochlear supporting cells function as macrophage-like cells and protect audiosensory receptor hair cells from pathogens. Sci Rep 2020; 10:6740. [PMID: 32317718 PMCID: PMC7174420 DOI: 10.1038/s41598-020-63654-9] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2019] [Accepted: 04/01/2020] [Indexed: 12/25/2022] Open
Abstract
To protect the audiosensory organ from tissue damage from the immune system, the inner ear is separated from the circulating immune system by the blood-labyrinth barrier, which was previously considered an immune-privileged site. Recent studies have shown that macrophages are distributed in the cochlea, especially in the spiral ligament, spiral ganglion, and stria vascularis; however, the direct pathogen defence mechanism used by audiosensory receptor hair cells (HCs) has remained obscure. Here, we show that HCs are protected from pathogens by surrounding accessory supporting cells (SCs) and greater epithelial ridge (GER or Kölliker’s organ) cells (GERCs). In isolated murine cochlear sensory epithelium, we established Theiler’s murine encephalomyelitis virus, which infected the SCs and GERCs, but very few HCs. The virus-infected SCs produced interferon (IFN)-α/β, and the viruses efficiently infected the HCs in the IFN-α/β receptor-null sensory epithelium. Interestingly, the virus-infected SCs and GERCs expressed macrophage marker proteins and were eliminated from the cell layer by cell detachment. Moreover, lipopolysaccharide induced phagocytosis of the SCs without cell detachment, and the SCs phagocytosed the bacteria. These results reveal that SCs function as macrophage-like cells, protect adjacent HCs from pathogens, and provide a novel anti-infection inner ear immune system.
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Affiliation(s)
- Yushi Hayashi
- Department of Molecular Oncology, Institute for Advanced Medical Sciences, Nippon Medical School, Tokyo, Japan
| | - Hidenori Suzuki
- Division of Morphological and Biomolecular Research, Nippon Medical School, Tokyo, Japan
| | - Wataru Nakajima
- Department of Molecular Oncology, Institute for Advanced Medical Sciences, Nippon Medical School, Tokyo, Japan
| | - Ikuno Uehara
- Department of Molecular Oncology, Institute for Advanced Medical Sciences, Nippon Medical School, Tokyo, Japan
| | - Atsuko Tanimura
- Department of Molecular Oncology, Institute for Advanced Medical Sciences, Nippon Medical School, Tokyo, Japan
| | - Toshiki Himeda
- Department of Microbiology, Kanazawa Medical University School of Medicine, Ishikawa, Japan
| | - Satoshi Koike
- Neurovirology Project, Tokyo Metropolitan Institute of Medical Science, Tokyo, Japan
| | - Tatsuya Katsuno
- Department of Otolaryngology, Head and Neck Surgery, Kyoto University, Kyoto, Japan
| | - Shin-Ichiro Kitajiri
- Department of Otolaryngology, Head and Neck Surgery, Kyoto University, Kyoto, Japan
| | - Naoto Koyanagi
- Division of Molecular Virology, Department of Microbiology and Immunology, The Institute of Medical Science, The University of Tokyo, Tokyo, Japan
| | - Yasushi Kawaguchi
- Division of Molecular Virology, Department of Microbiology and Immunology, The Institute of Medical Science, The University of Tokyo, Tokyo, Japan
| | - Koji Onomoto
- Division of Molecular Immunology, Medical Mycology Research Center, Chiba University, Chiba, Japan
| | - Hiroki Kato
- Laboratory of Molecular Genetics, Institute for Virus Research, Kyoto University, Kyoto, Japan
| | - Mitsutoshi Yoneyama
- Division of Molecular Immunology, Medical Mycology Research Center, Chiba University, Chiba, Japan
| | - Takashi Fujita
- Laboratory of Molecular Genetics, Institute for Virus Research, Kyoto University, Kyoto, Japan
| | - Nobuyuki Tanaka
- Department of Molecular Oncology, Institute for Advanced Medical Sciences, Nippon Medical School, Tokyo, Japan.
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Mitochondrial Damage and Necroptosis in Aging Cochlea. Int J Mol Sci 2020; 21:ijms21072505. [PMID: 32260310 PMCID: PMC7177801 DOI: 10.3390/ijms21072505] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2020] [Revised: 04/02/2020] [Accepted: 04/02/2020] [Indexed: 12/14/2022] Open
Abstract
Age-related hearing loss (ARHL) is an irreversible, progressive neurodegenerative disorder and is presently untreatable. Previous studies using animal models have suggested mitochondrial damage and programmed cell death to be involved with ARHL. Thus, we further investigated the pathophysiologic role of mitochondria and necroptosis in aged C57BL/6J male mice. Aged mice (20 months old) exhibited a significant loss of hearing, number of hair cells, neuronal fibers, and synaptic ribbons compared to young mice. Ultrastructural analysis of aged cochleae revealed damaged mitochondria with absent or disorganized cristae. Aged mice also showed significant decrease in cochlear blood flow, and exhibited increase in gene expression of proinflammatory cytokines (IL-1β, IL-6, and TNF-α), receptor-interacting serine/threonine-protein kinase 1 and 3 (RIPK1 and RIPK3) and the pseudokinase mixed-lineage kinase domain-like (MLKL). Immunofluorescence (IF) assays of cytochrome C oxidase I (COX1) confirmed mitochondrial dysfunction in aged cochleae, which correlated with the degree of mitochondrial morphological damage. IF assays also revealed localization and increased expression of RIPK3 in sensorineural tissues that underwent significant necroptosis (inner and outer hair cells and stria vascularis). Together, our data shows that the aging cochlea exhibits damaged mitochondria, enhanced synthesis of proinflammatory cytokines, and provides new evidence of necroptosis in the aging cochlea in in vivo.
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Wen L, Fan Z, Mikulski Z, Ley K. Imaging of the immune system - towards a subcellular and molecular understanding. J Cell Sci 2020; 133:133/5/jcs234922. [PMID: 32139598 DOI: 10.1242/jcs.234922] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
Immune responses involve many types of leukocytes that traffic to the site of injury, recognize the insult and respond appropriately. Imaging of the immune system involves a set of methods and analytical tools that are used to visualize immune responses at the cellular and molecular level as they occur in real time. We will review recent and emerging technological advances in optical imaging, and their application to understanding the molecular and cellular responses of neutrophils, macrophages and lymphocytes. Optical live-cell imaging provides deep mechanistic insights at the molecular, cellular, tissue and organism levels. Live-cell imaging can capture quantitative information in real time at subcellular resolution with minimal phototoxicity and repeatedly in the same living cells or in accessible tissues of the living organism. Advanced FRET probes allow tracking signaling events in live cells. Light-sheet microscopy allows for deeper tissue penetration in optically clear samples, enriching our understanding of the higher-level organization of the immune response. Super-resolution microscopy offers insights into compartmentalized signaling at a resolution beyond the diffraction limit, approaching single-molecule resolution. This Review provides a current perspective on live-cell imaging in vitro and in vivo with a focus on the assessment of the immune system.
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Affiliation(s)
- Lai Wen
- Laboratory of Inflammation Biology, La Jolla Institute for Immunology, 9420 Athena Circle Drive, La Jolla, CA 92037, USA
| | - Zhichao Fan
- Department of Immunology, School of Medicine, UConn Health, 263 Farmington Avenue, Farmington, CT 06030, USA
| | - Zbigniew Mikulski
- Microscopy Core Facility, La Jolla Institute for Immunology, 9420 Athena Circle Drive, La Jolla, CA 92037, USA
| | - Klaus Ley
- Laboratory of Inflammation Biology, La Jolla Institute for Immunology, 9420 Athena Circle Drive, La Jolla, CA 92037, USA .,Department of Bioengineering, University of California, San Diego, 9500 Gilman Drive, La Jolla, CA 92093, USA
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Ahmadi N, Gausterer JC, Honeder C, Mötz M, Schöpper H, Zhu C, Saidov N, Gabor F, Arnoldner C. Long-term effects and potential limits of intratympanic dexamethasone-loaded hydrogels combined with dexamethasone-eluting cochlear electrodes in a low-insertion trauma Guinea pig model. Hear Res 2019; 384:107825. [PMID: 31669876 DOI: 10.1016/j.heares.2019.107825] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/26/2019] [Revised: 09/07/2019] [Accepted: 10/16/2019] [Indexed: 12/11/2022]
Abstract
Cochlear implantation has become the most effective hearing restoration method and is one of the great advances in modern medicine. Early implants have been continuously developed into more efficient devices, and electro-acoustic stimulation is increasingly expanding the indication criteria for cochlear implants to patients with more residual hearing. Therefore, protecting the cochlear structures and maintaining its intrinsic capacities like residual hearing has become more important than ever before. In the present study, we aimed to assess the long-term protective effects of a dexamethasone-eluting electrode combined with the preoperative intratympanic application of a dexamethasone-loaded thermoreversible hydrogel in a cochlear implant guinea pig model. 40 normal-hearing animals were equally randomized into a control group receiving an unloaded hydrogel and a non-eluting electrode, a group receiving a dexamethasone-loaded hydrogel and a non-eluting electrode, a group receiving an unloaded hydrogel and a dexamethasone-eluting electrode and a group receiving both a dexamethasone-loaded hydrogel and a dexamethasone-eluting electrode. Residual hearing and impedances were investigated during a period of 120 days. Tissue response and histological changes of cochlear structures were analyzed at the end of the experiments. Treatment with dexamethasone did not show a significant protective effect on residual hearing independent of treatment group. Although the majority of the cochleae didn't exhibit any signs of electrode insertion trauma, a small degree of tissue response could be observed in all animals without a significant difference between the groups. Foreign body giant cells and osteogenesis were significantly associated with tissue response. Hair cells, synapsin-1-positive cells and spiral ganglion cells were preserved in all study groups. Cochlear implantation using a dexamethasone-eluting electrode alone and in combination with a dexamethasone-loaded hydrogel significantly protected auditory nerve fibers on day 120. Post-implantation impedances were equal across study groups and remained stable over the duration of the experiment. In this study we were able to show that use of a dexamethasone-eluting electrode alone and in combination with preoperative application of dexamethasone-loaded hydrogel significantly protects auditory nerve fibers. Furthermore, we have shown that a cochlear implantation-associated hearing threshold shift and tissue response may not be completely prevented by the sole application of dexamethasone.
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Affiliation(s)
- Navid Ahmadi
- Department of Otorhinolaryngology, Head and Neck Surgery, Medical University of Vienna, Vienna, Austria.
| | - Julia Clara Gausterer
- Department of Pharmaceutical Technology and Biopharmaceutics, University of Vienna, Vienna, Austria.
| | - Clemens Honeder
- Department of Otorhinolaryngology, Head and Neck Surgery, Medical University of Vienna, Vienna, Austria.
| | - Marlene Mötz
- Department of Pathobiology, Institute of Anatomy, Histology and Embryology, University of Veterinary Medicine Vienna, Austria.
| | - Hanna Schöpper
- Department of Pathobiology, Institute of Anatomy, Histology and Embryology, University of Veterinary Medicine Vienna, Austria.
| | - Chengjing Zhu
- Department of Otorhinolaryngology, Head and Neck Surgery, Medical University of Vienna, Vienna, Austria.
| | - Nodir Saidov
- Department of Otorhinolaryngology, Head and Neck Surgery, Medical University of Vienna, Vienna, Austria.
| | - Franz Gabor
- Department of Pharmaceutical Technology and Biopharmaceutics, University of Vienna, Vienna, Austria.
| | - Christoph Arnoldner
- Department of Otorhinolaryngology, Head and Neck Surgery, Medical University of Vienna, Vienna, Austria.
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Ito T, Inui H, Miyasaka T, Shiozaki T, Fujita H, Yamanaka T, Kichikawa K, Kitahara T. Relationship between changes in hearing function and volumes of endolymphatic hydrops after endolymphatic sac drainage. Acta Otolaryngol 2019; 139:739-746. [PMID: 31274039 DOI: 10.1080/00016489.2019.1630757] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
Background: Endolymphatic sac drainage (ELSD) may have a positive effect on endolymphatic hydrops (EH) and may help to preserve inner ear function. However, the relationship between changes in EH volumes and hearing function after ELSD has not been described. Objectives: We aimed to reveal the factors related to changes in hearing and EH following ELSD. Material and Methods: Twenty-one patients who received ELSD were enrolled. Pure tone audiometry and 3-T magnetic resonance imaging (MRI) 4 h after intravenous injection of gadolinium enhancement were performed just before surgery and 2 years later. To characterize the endolymphatic space (ELS), we measured the volume of the total fluid (TFS) and ELS and calculated the ratio of ELS to TFS (ELS ratio). Results: The ELS ratio of the patients who showed hearing improvement was 18.5 ± 11.4% before surgery and 23.9 ± 14.3% after. For those with no change, it was 29.7 ± 10.8% before and 29.4 ± 9.5% after, and in patients with worsened hearing function it was 22.7 ± 7.5% before and 27.2 ± 13.4% after. Conclusion: We found no correlation between the changes in hearing function and the volume of EH after ELSD.
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Affiliation(s)
- Taeko Ito
- Department of Otolaryngology – Head and Neck Surgery, Nara Medical University, Kashihara, Japan
| | - Hiroshi Inui
- Department of Otolaryngology – Head and Neck Surgery, Nara Medical University, Kashihara, Japan
- Inui ENT Clinic, Sakurai, Japan
| | | | - Tomoyuki Shiozaki
- Department of Otolaryngology – Head and Neck Surgery, Nara Medical University, Kashihara, Japan
| | - Hiroto Fujita
- Department of Otolaryngology – Head and Neck Surgery, Nara Medical University, Kashihara, Japan
| | - Toshiaki Yamanaka
- Department of Otolaryngology – Head and Neck Surgery, Nara Medical University, Kashihara, Japan
| | | | - Tadashi Kitahara
- Department of Otolaryngology – Head and Neck Surgery, Nara Medical University, Kashihara, Japan
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Noble KV, Liu T, Matthews LJ, Schulte BA, Lang H. Age-Related Changes in Immune Cells of the Human Cochlea. Front Neurol 2019; 10:895. [PMID: 31474935 PMCID: PMC6707808 DOI: 10.3389/fneur.2019.00895] [Citation(s) in RCA: 31] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2019] [Accepted: 08/02/2019] [Indexed: 12/12/2022] Open
Abstract
Age-related hearing loss is a chronic degenerative disorder affecting one in two individuals above the age of 75. Current population projections predict a steady climb in the number of older individuals making the search for interventions to prevent or reverse this disorder even more critical. There is growing acceptance that aberrant activity of resident or infiltrating immune cells, such as macrophages, is a major factor contributing to the onset and progression of age-related degenerative diseases. However, how macrophage populations and their functionally-driven morphological characteristics change with age in the human cochlea remains largely unknown. In this study, we employed immunohistochemical approaches along with confocal and super-resolution imaging, three-dimensional reconstructions, and quantitative analysis to determine age-related changes in macrophage numbers and morphology as well as interactions with other cell-types and structures of the auditory nerve and lateral wall in the human cochlea. In the cochlea of human ears from young and middle aged adults those macrophages in the auditory nerve assumed a worm-like structure in contrast to those in the spiral ligament or associated with the dense microvascular network in the stria vascularis which exhibited a highly ramified morphology. Macrophages in both the auditory nerve and cochlear lateral wall showed morphological alterations with age. The population of activated macrophages in the auditory nerve increased in cochleas obtained from older donors. Dual-immunohistochemical staining with macrophage, myelin, and neuronal markers revealed increased interactions of macrophages with the glial and neuronal components of the aged auditory nerve. These findings implicate the involvement of abnormal macrophage-glia interactions in age-related physiological and pathological alterations in the human cochlea. There is clearly a need to further investigate the contribution of macrophage-associated inflammatory dysregulation in human presbyacusis.
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Affiliation(s)
- Kenyaria V. Noble
- Department of Pathology and Laboratory Medicine, Medical University of South Carolina, Charleston, SC, United States
| | - Ting Liu
- Department of Pathology and Laboratory Medicine, Medical University of South Carolina, Charleston, SC, United States
| | - Lois J. Matthews
- Department of Otolaryngology-Head and Neck Surgery, Medical University of South Carolina, Charleston, SC, United States
| | - Bradley A. Schulte
- Department of Pathology and Laboratory Medicine, Medical University of South Carolina, Charleston, SC, United States
- Department of Otolaryngology-Head and Neck Surgery, Medical University of South Carolina, Charleston, SC, United States
| | - Hainan Lang
- Department of Pathology and Laboratory Medicine, Medical University of South Carolina, Charleston, SC, United States
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Liu W, Luque M, Glueckert R, Danckwardt-Lillieström N, Nordström CK, Schrott-Fischer A, Rask-Andersen H. Expression of Na/K-ATPase subunits in the human cochlea: a confocal and super-resolution microscopy study with special reference to auditory nerve excitation and cochlear implantation. Ups J Med Sci 2019; 124:168-179. [PMID: 31460814 PMCID: PMC6758701 DOI: 10.1080/03009734.2019.1653408] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
Background: For the first time the expression of the ion transport protein sodium/potassium-ATPase and its isoforms was analyzed in the human cochlea using light- and confocal microscopy as well as super-resolution structured illumination microscopy. It may increase our understanding of its role in the propagation and processing of action potentials in the human auditory nerve and how electric nerve responses are elicited from auditory prostheses. Material and methods: Archival human cochlear sections were obtained from trans-cochlear surgeries. Antibodies against the Na/K-ATPase β1 isoform together with α1 and α3 were used for immunohistochemistry. An algorithm was applied to assess the expression in various domains. Results: Na/K ATPase β1 subunit was expressed, mostly combined with the α1 isoform. Neurons expressed the β1 subunit combined with α3, while satellite glial cells expressed the α1 isoform without recognized association with β1. Types I and II spiral ganglion neurons and efferent fibers expressed the Na/K-ATPase α3 subunit. Inner hair cells, nerve fibers underneath, and efferent and afferent fibers in the organ of Corti also expressed α1. The highest activity of Na/K-ATPase β1 was at the inner hair cell/nerve junction and spiral prominence. Conclusion: The human auditory nerve displays distinct morphologic features represented in its molecular expression. It was found that electric signals generated via hair cells may not go uninterrupted across the spiral ganglion, but are locally processed. This may be related to particular filtering properties in the human acoustic pathway.
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Affiliation(s)
- Wei Liu
- Department of Surgical Sciences, Section of Otolaryngology, Uppsala University Hospital, Uppsala, Sweden
- Wei Liu
| | - Maria Luque
- Department of Otolaryngology, Medical University of Innsbruck, Innsbruck, Austria
| | - Rudolf Glueckert
- Department of Otolaryngology, Medical University of Innsbruck, Innsbruck, Austria
| | | | - Charlotta Kämpfe Nordström
- Department of Surgical Sciences, Section of Otolaryngology, Uppsala University Hospital, Uppsala, Sweden
| | | | - Helge Rask-Andersen
- Department of Surgical Sciences, Head and Neck Surgery, Section of Otolaryngology, Uppsala University Hospital, Uppsala, Sweden
- CONTACT Helge Rask-Andersen Department of Surgical Sciences, Head and Neck Surgery, Section of Otolaryngology, Uppsala University Hospital, SE-751 85, Uppsala, Sweden
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Liu W, Kämpfe Nordström C, Danckwardt-Lillieström N, Rask-Andersen H. Human Inner Ear Immune Activity: A Super-Resolution Immunohistochemistry Study. Front Neurol 2019; 10:728. [PMID: 31354608 PMCID: PMC6635812 DOI: 10.3389/fneur.2019.00728] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2019] [Accepted: 06/19/2019] [Indexed: 12/20/2022] Open
Abstract
Background: Like the brain, the human inner ear was long thought to be devoid of immune activity. Only the endolymphatic sac (ES) was known to be endowed with white blood cells that could process antigens and serve as an immunologic defense organ for the entire inner ear. Unexpectedly, the cochlear and vestibular organs, including the eighth cranial nerve, were recently shown to contain macrophages whose functions and implication in ear disease are somewhat undefined. Here, we review recent inner ear findings in man and extend the analyses to the vestibular nerve using super-resolution structured illumination microscopy (SR-SIM). Materials and Methods: Human ESs and cochleae were collected during surgery to treat patients with vestibular schwannoma and life-threatening petro-clival meningioma compressing the brainstem. The ESs and cochleae were placed in fixative, decalcified, and rapidly frozen and cryostat sectioned. Antibodies against ionized calcium-binding adaptor molecule 1-expressing cells (IBA1 cells), laminin β2 and type IV collagen TUJ1, cytokine fractalkine (CX3CL1), toll-like receptor 4 (TLR4), CD68, CD11b, CD4, CD8, the major histocompatibility complex type II (MHCII), and the microglial marker TEME119 were used. Results: IBA1-positive cells were present in the ESs, the cochlea, central and peripheral axons of the cochlear nerve, and the vestibular nerve trunk. IBA1 cells were found in the cochlear lateral wall, spiral limbus, and spiral ganglion. Notable variants of IBA1 cells adhered to neurons with “synapse-like” specializations and cytoplasmic projections. Slender IBA1 cells occasionally protracted into the basal lamina of the Schwann cells and had intimate contact with surrounding axons. Discussion: The human eighth nerve may be under the control of a well-developed macrophage cell system. A small number of CD4+ and CD8+ cells were found in the ES and occasionally in the cochlea, mostly located in the peripheral region of Rosenthal's canal. A neuro-immunologic axis may exist in the human inner ear that could play a role in the protection of the auditory nerve. The implication of the macrophage system during disease, surgical interventions, and cell-based transplantation should be further explored.
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Affiliation(s)
- Wei Liu
- Section of Otolaryngology, Department of Surgical Sciences, Uppsala University Hospital, Uppsala, Sweden
| | - Charlotta Kämpfe Nordström
- Section of Otolaryngology, Department of Surgical Sciences, Uppsala University Hospital, Uppsala, Sweden
| | | | - Helge Rask-Andersen
- Section of Otolaryngology, Department of Surgical Sciences, Uppsala University Hospital, Uppsala, Sweden
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Köles L, Szepesy J, Berekméri E, Zelles T. Purinergic Signaling and Cochlear Injury-Targeting the Immune System? Int J Mol Sci 2019; 20:ijms20122979. [PMID: 31216722 PMCID: PMC6627352 DOI: 10.3390/ijms20122979] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2019] [Revised: 06/14/2019] [Accepted: 06/14/2019] [Indexed: 02/06/2023] Open
Abstract
Hearing impairment is the most common sensory deficit, affecting more than 400 million people worldwide. Sensorineural hearing losses currently lack any specific or efficient pharmacotherapy largely due to the insufficient knowledge of the pathomechanism. Purinergic signaling plays a substantial role in cochlear (patho)physiology. P2 (ionotropic P2X and the metabotropic P2Y) as well as adenosine receptors expressed on cochlear sensory and non-sensory cells are involved mostly in protective mechanisms of the cochlea. They are implicated in the sensitivity adjustment of the receptor cells by a K+ shunt and can attenuate the cochlear amplification by modifying cochlear micromechanics. Cochlear blood flow is also regulated by purines. Here, we propose to comprehend this field with the purine-immune interactions in the cochlea. The role of harmful immune mechanisms in sensorineural hearing losses has been emerging in the horizon of cochlear pathologies. In addition to decreasing hearing sensitivity and increasing cochlear blood supply, influencing the immune system can be the additional avenue for pharmacological targeting of purinergic signaling in the cochlea. Elucidating this complexity of purinergic effects on cochlear functions is necessary and it can result in development of new therapeutic approaches in hearing disabilities, especially in the noise-induced ones.
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Affiliation(s)
- László Köles
- Department of Pharmacology and Pharmacotherapy, Semmelweis University, H-1089 Budapest, Hungary.
| | - Judit Szepesy
- Department of Pharmacology and Pharmacotherapy, Semmelweis University, H-1089 Budapest, Hungary.
| | - Eszter Berekméri
- Department of Pharmacology and Pharmacotherapy, Semmelweis University, H-1089 Budapest, Hungary.
- Department of Ecology, University of Veterinary Medicine, H-1078 Budapest, Hungary.
| | - Tibor Zelles
- Department of Pharmacology and Pharmacotherapy, Semmelweis University, H-1089 Budapest, Hungary.
- Department of Pharmacology, Institute of Experimental Medicine, Hungarian Academy of Sciences, H-1083 Budapest, Hungary.
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