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Wu M, Fletcher EL, Chinnery HR, Downie LE, Mueller SN. Redefining our vision: an updated guide to the ocular immune system. Nat Rev Immunol 2024:10.1038/s41577-024-01064-y. [PMID: 39215057 DOI: 10.1038/s41577-024-01064-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/01/2024] [Indexed: 09/04/2024]
Abstract
Balanced immune responses in the eyes are crucial to preserve vision. The ocular immune system has long been considered distinct, owing to the so-called 'immune privilege' of its component tissues. More recently, intravital imaging and transcriptomic techniques have reshaped scientific understanding of the ocular immune landscape, such as revealing the specialization of immune cell populations in the various tissues of the eye. As knowledge of the phenotypes of corneal and retinal immune cells has evolved, links to both the systemic immune system, and the central and peripheral nervous systems, have been identified. Using intravital imaging, T cells have recently been found to reside in, and actively patrol, the healthy human cornea. Disease-associated retinal microglia with links to retinal degeneration have also been identified. This Review provides an updated guide to the ocular immune system, highlighting current knowledge of the immune cells that are present in steady-state and specific diseased ocular tissues, as well as evidence for their relationship to systemic disease. In addition, we discuss emerging intravital imaging techniques that can be used to visualize immune cell morphology and dynamics in living human eyes and how these could be applied to advance understanding of the human immune system.
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Affiliation(s)
- Mengliang Wu
- Department of Optometry and Vision Sciences, The University of Melbourne, Carlton, Victoria, Australia
- Department of Microbiology and Immunology, The University of Melbourne, at The Peter Doherty Institute for Infection and Immunity, Melbourne, Victoria, Australia
| | - Erica L Fletcher
- Department of Anatomy and Physiology, The University of Melbourne, Carlton, Victoria, Australia
| | - Holly R Chinnery
- Department of Optometry and Vision Sciences, The University of Melbourne, Carlton, Victoria, Australia.
- Lions Eye Institute, Nedlands, Western Australia, Australia.
- Optometry, The University of Western Australia, Crawley, Western Australia, Australia.
| | - Laura E Downie
- Department of Optometry and Vision Sciences, The University of Melbourne, Carlton, Victoria, Australia.
| | - Scott N Mueller
- Department of Microbiology and Immunology, The University of Melbourne, at The Peter Doherty Institute for Infection and Immunity, Melbourne, Victoria, Australia.
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Gong Q, Huang K, Li K, Tong Y, Zhao J, Wang H, Xu Z, Lin M, Lu F, Hu L. Structural and functional changes of binocular corneal innervation and ocular surface function after unilateral SMILE and tPRK. Br J Ophthalmol 2024:bjo-2023-324358. [PMID: 38527771 DOI: 10.1136/bjo-2023-324358] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2023] [Accepted: 02/18/2024] [Indexed: 03/27/2024]
Abstract
AIMS To evaluate the bilateral changes in the sub-basal nerve plexus of the cornea and ocular surface function after unilateral small incision lenticule extraction (SMILE) and transepithelial photorefractive keratectomy (tPRK) procedures. METHODS 34 patients were enrolled in the study and underwent unilateral SMILE (21 of 34 patients) or unilateral tPRK (13 of 34 patients). Complete ophthalmic examinations, tear film function tests and Cochet-Bonnet esthesiometry were conducted to assess the effects of the surgeries on the corneal nerves and tear function. Morphological changes were assessed using in vivo confocal microscopy to evaluate the corneal sub-basal nerve plexus and dendritic cells. ELISA was used to measure the tear neuromediators. Clinical and morphological data at each follow-up point were compared with preoperative baseline values. RESULTS All patients who underwent unilateral SMILE or tPRK procedures exhibited bilateral corneal nerve degenerative changes, decreased corneal sensitivity, worsening of dry eye symptoms and changes in bilateral tear neuromediators. In the SMILE group, bilateral corneal sensitivity was positively correlated with corneal nerve fibre length and negatively correlated with dendritic cell area. The dry eye severity was negatively correlated with corneal sensitivity. Tear levels of substance P and nerve growth factor were positively correlated with mean dendritic cell area and dry eye severity, but negatively correlated with corneal sensitivity. In the tPRK group, bilateral corneal sensitivity was positively correlated with corneal nerve fibre density. CONCLUSIONS Unilateral refractive surgery may bilaterally affect the morphology and function of corneal nerves and ocular surface status postoperatively.
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Affiliation(s)
- Qianwen Gong
- National Clinical Research Center for Ocular Diseases, Eye Hospital, Wenzhou Medical University, Wenzhou, Zhejiang, China
- State Key Laboratory of Ophthalmology, Optometry and Visual Science, Eye Hospital, Wenzhou Medical University, Wenzhou, Zhejiang, China
| | - Kaiyan Huang
- National Clinical Research Center for Ocular Diseases, Eye Hospital, Wenzhou Medical University, Wenzhou, Zhejiang, China
- State Key Laboratory of Ophthalmology, Optometry and Visual Science, Eye Hospital, Wenzhou Medical University, Wenzhou, Zhejiang, China
| | - Kexin Li
- National Clinical Research Center for Ocular Diseases, Eye Hospital, Wenzhou Medical University, Wenzhou, Zhejiang, China
- State Key Laboratory of Ophthalmology, Optometry and Visual Science, Eye Hospital, Wenzhou Medical University, Wenzhou, Zhejiang, China
| | - Yixuan Tong
- National Clinical Research Center for Ocular Diseases, Eye Hospital, Wenzhou Medical University, Wenzhou, Zhejiang, China
- State Key Laboratory of Ophthalmology, Optometry and Visual Science, Eye Hospital, Wenzhou Medical University, Wenzhou, Zhejiang, China
| | - Jian Zhao
- National Clinical Research Center for Ocular Diseases, Eye Hospital, Wenzhou Medical University, Wenzhou, Zhejiang, China
- State Key Laboratory of Ophthalmology, Optometry and Visual Science, Eye Hospital, Wenzhou Medical University, Wenzhou, Zhejiang, China
| | - Hui Wang
- National Clinical Research Center for Ocular Diseases, Eye Hospital, Wenzhou Medical University, Wenzhou, Zhejiang, China
- State Key Laboratory of Ophthalmology, Optometry and Visual Science, Eye Hospital, Wenzhou Medical University, Wenzhou, Zhejiang, China
| | - Zhiqiang Xu
- National Clinical Research Center for Ocular Diseases, Eye Hospital, Wenzhou Medical University, Wenzhou, Zhejiang, China
- State Key Laboratory of Ophthalmology, Optometry and Visual Science, Eye Hospital, Wenzhou Medical University, Wenzhou, Zhejiang, China
| | - Meng Lin
- National Clinical Research Center for Ocular Diseases, Eye Hospital, Wenzhou Medical University, Wenzhou, Zhejiang, China
- State Key Laboratory of Ophthalmology, Optometry and Visual Science, Eye Hospital, Wenzhou Medical University, Wenzhou, Zhejiang, China
| | - Fan Lu
- National Clinical Research Center for Ocular Diseases, Eye Hospital, Wenzhou Medical University, Wenzhou, Zhejiang, China
- State Key Laboratory of Ophthalmology, Optometry and Visual Science, Eye Hospital, Wenzhou Medical University, Wenzhou, Zhejiang, China
| | - Liang Hu
- National Clinical Research Center for Ocular Diseases, Eye Hospital, Wenzhou Medical University, Wenzhou, Zhejiang, China
- State Key Laboratory of Ophthalmology, Optometry and Visual Science, Eye Hospital, Wenzhou Medical University, Wenzhou, Zhejiang, China
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Mardelle U, Bretaud N, Daher C, Feuillet V. From pain to tumor immunity: influence of peripheral sensory neurons in cancer. Front Immunol 2024; 15:1335387. [PMID: 38433844 PMCID: PMC10905387 DOI: 10.3389/fimmu.2024.1335387] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2023] [Accepted: 01/29/2024] [Indexed: 03/05/2024] Open
Abstract
The nervous and immune systems are the primary sensory interfaces of the body, allowing it to recognize, process, and respond to various stimuli from both the external and internal environment. These systems work in concert through various mechanisms of neuro-immune crosstalk to detect threats, provide defense against pathogens, and maintain or restore homeostasis, but can also contribute to the development of diseases. Among peripheral sensory neurons (PSNs), nociceptive PSNs are of particular interest. They possess a remarkable capability to detect noxious stimuli in the periphery and transmit this information to the brain, resulting in the perception of pain and the activation of adaptive responses. Pain is an early symptom of cancer, often leading to its diagnosis, but it is also a major source of distress for patients as the disease progresses. In this review, we aim to provide an overview of the mechanisms within tumors that are likely to induce cancer pain, exploring a range of factors from etiological elements to cellular and molecular mediators. In addition to transmitting sensory information to the central nervous system, PSNs are also capable, when activated, to produce and release neuropeptides (e.g., CGRP and SP) from their peripheral terminals. These neuropeptides have been shown to modulate immunity in cases of inflammation, infection, and cancer. PSNs, often found within solid tumors, are likely to play a significant role in the tumor microenvironment, potentially influencing both tumor growth and anti-tumor immune responses. In this review, we discuss the current state of knowledge about the degree of sensory innervation in tumors. We also seek to understand whether and how PSNs may influence the tumor growth and associated anti-tumor immunity in different mouse models of cancer. Finally, we discuss the extent to which the tumor is able to influence the development and functions of the PSNs that innervate it.
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Affiliation(s)
- Ugo Mardelle
- Aix-Marseille Université, Centre National de la Recherche Scientifique (CNRS), Institut National de la Santé et de la Recherche Médicale (INSERM), CIML, Centre d'Immunologie de Marseille-Luminy, Marseille, France
| | - Ninon Bretaud
- Aix-Marseille Université, Centre National de la Recherche Scientifique (CNRS), Institut National de la Santé et de la Recherche Médicale (INSERM), CIML, Centre d'Immunologie de Marseille-Luminy, Marseille, France
| | - Clara Daher
- Aix-Marseille Université, Centre National de la Recherche Scientifique (CNRS), Institut National de la Santé et de la Recherche Médicale (INSERM), CIML, Centre d'Immunologie de Marseille-Luminy, Marseille, France
| | - Vincent Feuillet
- Aix-Marseille Université, Centre National de la Recherche Scientifique (CNRS), Institut National de la Santé et de la Recherche Médicale (INSERM), CIML, Centre d'Immunologie de Marseille-Luminy, Marseille, France
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Lee SH, Chun YS, Kim KW. Ocular surface parameter changes in the untreated fellow eye after unilateral cataract surgery with short-term administration of anti-inflammatory eye drops. Sci Rep 2024; 14:1080. [PMID: 38212520 PMCID: PMC10784480 DOI: 10.1038/s41598-024-51764-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2023] [Accepted: 01/09/2024] [Indexed: 01/13/2024] Open
Abstract
This study aimed to investigate the changes in clinical parameters of dry eye disease and meibomian gland dysfunction in both the operated and untreated fellow eyes of patients who underwent unilateral cataract surgery with the short-term administration of anti-inflammatory eye drops in the surgical eye. The medical charts of 57 consecutive patients who underwent unilateral cataract surgery and received 1% prednisolone acetate and non-steroidal anti-inflammatory drug (NSAID, 0.1% bromfenac sodium) eye drops were reviewed. The preoperative ocular surface disease index questionnaire score (38.9 ± 20.5) decreased significantly to 15.2 ± 16.4 at post-surgical 1 week and further to 12.8 ± 11.4 after 1 month. Although meibum quality grade increased and corneal sensitivity decreased at 1 week in operated eyes, corneal erosion scores and Sjogren's International Collaborative Clinical Alliance ocular staining scores even improved over a month in the untreated fellow eyes. The tear matrix metalloproteinase (MMP)-9 grade decreased in both operated eyes and untreated fellow eyes after 1 month from surgery. In conclusion, the short-term topical anti-inflammatory treatment using steroid and NSAID eye drops in the operated eye after cataract surgery decreased subjective ocular surface discomfort and improved ocular surface staining scores and tear MMP-9 expression in the untreated fellow eyes.
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Affiliation(s)
- Seung Hyeun Lee
- Department of Ophthalmology, Chung-Ang University College of Medicine, Chung-Ang University Hospital, 102 Heukseok-ro, Dongjak-gu, Seoul, 06973, Republic of Korea
| | - Yeoun Sook Chun
- Department of Ophthalmology, Chung-Ang University College of Medicine, Chung-Ang University Hospital, 102 Heukseok-ro, Dongjak-gu, Seoul, 06973, Republic of Korea
| | - Kyoung Woo Kim
- Department of Ophthalmology, Chung-Ang University College of Medicine, Chung-Ang University Hospital, 102 Heukseok-ro, Dongjak-gu, Seoul, 06973, Republic of Korea.
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Dempsey MP, Conrady CD. The Host-Pathogen Interplay: A Tale of Two Stories within the Cornea and Posterior Segment. Microorganisms 2023; 11:2074. [PMID: 37630634 PMCID: PMC10460047 DOI: 10.3390/microorganisms11082074] [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: 06/05/2023] [Revised: 08/10/2023] [Accepted: 08/10/2023] [Indexed: 08/27/2023] Open
Abstract
Ocular infectious diseases are an important cause of potentially preventable vision loss and blindness. In the following manuscript, we will review ocular immunology and the pathogenesis of herpesviruses and Pseudomonas aeruginosa infections of the cornea and posterior segment. We will highlight areas of future research and what is currently known to promote bench-to-bedside discoveries to improve clinical outcomes of these debilitating ocular diseases.
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Affiliation(s)
- Michael P. Dempsey
- Department of Ophthalmology and Visual Sciences, Truhlsen Eye Center, University of Nebraska Medical Center, Omaha, NE 68105, USA
| | - Christopher D. Conrady
- Department of Ophthalmology and Visual Sciences, Truhlsen Eye Center, University of Nebraska Medical Center, Omaha, NE 68105, USA
- Department of Pathology and Microbiology, University of Nebraska Medical Center, Omaha, NE 68198, USA
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Shiuey EJ, Zhang Q, Rapuano CJ, Ayres BD, Hammersmith KM, Nagra PK, Syed ZA. Prior Contralateral Penetrating Keratoplasty Is a Risk Factor for Second Eye Graft Rejection. Ocul Immunol Inflamm 2023; 31:257-262. [PMID: 35050842 DOI: 10.1080/09273948.2021.2024860] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Abstract
AIMS To determine whether prior penetrating keratoplasty (PK) in the contralateral eye increases risk of second eye PK graft rejection. METHODS Cohort study of 593 consecutive PKs in transplant-naïve eyes (500 unilateral cases, 93 second eyes). Outcomes were compared between PKs performed in eyes with versus without a history of prior contralateral eye PK. Risks of rejection and failure were estimated using Cox proportional hazards models. RESULTS Mean age was 53.7 ± 23.3 years; average follow-up was 4.00 ± 2.87 years. Rejection occurred in 211 (35.6%) grafts. The incidence of rejection was 34.0% in unilateral cases and 44.1% in second eyes with PK in the contralateral eye. Prior contralateral PK was a significant risk factor for graft rejection (HR = 1.42, 95% CI 1.01-2.01, p = .045). CONCLUSION Contralateral PK is associated with increased risk of second eye graft rejection. Loss of ocular immune privilege is a possible mechanism.
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Affiliation(s)
- Eric J Shiuey
- Sidney Kimmel Medical College, Thomas Jefferson University, Philadelphia, Pennsylvania, USA
| | - Qiang Zhang
- Sidney Kimmel Medical College, Thomas Jefferson University, Philadelphia, Pennsylvania, USA.,Biostatistics Consulting Core, Vickie and Jack Farber Vision Research Center, Wills Eye Hospital, Philadelphia, Pennsylvania, USA
| | - Christopher J Rapuano
- Sidney Kimmel Medical College, Thomas Jefferson University, Philadelphia, Pennsylvania, USA.,Cornea Service, Wills Eye Hospital, Philadelphia, Pennsylvania, USA
| | - Brandon D Ayres
- Sidney Kimmel Medical College, Thomas Jefferson University, Philadelphia, Pennsylvania, USA.,Cornea Service, Wills Eye Hospital, Philadelphia, Pennsylvania, USA
| | - Kristin M Hammersmith
- Sidney Kimmel Medical College, Thomas Jefferson University, Philadelphia, Pennsylvania, USA.,Cornea Service, Wills Eye Hospital, Philadelphia, Pennsylvania, USA
| | - Parveen K Nagra
- Sidney Kimmel Medical College, Thomas Jefferson University, Philadelphia, Pennsylvania, USA.,Cornea Service, Wills Eye Hospital, Philadelphia, Pennsylvania, USA
| | - Zeba A Syed
- Sidney Kimmel Medical College, Thomas Jefferson University, Philadelphia, Pennsylvania, USA.,Cornea Service, Wills Eye Hospital, Philadelphia, Pennsylvania, USA
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Puri S, Kenyon BM, Hamrah P. Immunomodulatory Role of Neuropeptides in the Cornea. Biomedicines 2022; 10:1985. [PMID: 36009532 PMCID: PMC9406019 DOI: 10.3390/biomedicines10081985] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2022] [Revised: 08/11/2022] [Accepted: 08/12/2022] [Indexed: 12/21/2022] Open
Abstract
The transparency of the cornea along with its dense sensory innervation and resident leukocyte populations make it an ideal tissue to study interactions between the nervous and immune systems. The cornea is the most densely innervated tissue of the body and possesses both immune and vascular privilege, in part due to its unique repertoire of resident immune cells. Corneal nerves produce various neuropeptides that have a wide range of functions on immune cells. As research in this area expands, further insights are made into the role of neuropeptides and their immunomodulatory functions in the healthy and diseased cornea. Much remains to be known regarding the details of neuropeptide signaling and how it contributes to pathophysiology, which is likely due to complex interactions among neuropeptides, receptor isoform-specific signaling events, and the inflammatory microenvironment in disease. However, progress in this area has led to an increase in studies that have begun modulating neuropeptide activity for the treatment of corneal diseases with promising results, necessitating the need for a comprehensive review of the literature. This review focuses on the role of neuropeptides in maintaining the homeostasis of the ocular surface, alterations in disease settings, and the possible therapeutic potential of targeting these systems.
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Affiliation(s)
- Sudan Puri
- Center for Translational Ocular Immunology, Tufts Medical Center, Tufts University School of Medicine, Boston, MA 02111, USA
- Department of Ophthalmology, Tufts Medical Center, Tufts University School of Medicine, Boston, MA 02111, USA
| | - Brendan M. Kenyon
- Center for Translational Ocular Immunology, Tufts Medical Center, Tufts University School of Medicine, Boston, MA 02111, USA
- Program in Neuroscience, Graduate School of Biomedical Sciences, Tufts University, Boston, MA 02111, USA
| | - Pedram Hamrah
- Center for Translational Ocular Immunology, Tufts Medical Center, Tufts University School of Medicine, Boston, MA 02111, USA
- Department of Ophthalmology, Tufts Medical Center, Tufts University School of Medicine, Boston, MA 02111, USA
- Program in Neuroscience, Graduate School of Biomedical Sciences, Tufts University, Boston, MA 02111, USA
- Departments of Immunology and Neuroscience, Tufts University School of Medicine, Boston, MA 02111, USA
- Cornea Service, Tufts New England Eye Center, Boston, MA 02111, USA
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8
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Modulating the tachykinin: Role of substance P and neurokinin receptor expression in ocular surface disorders. Ocul Surf 2022; 25:142-153. [PMID: 35779793 DOI: 10.1016/j.jtos.2022.06.007] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2022] [Revised: 06/21/2022] [Accepted: 06/24/2022] [Indexed: 01/19/2023]
Abstract
Substance P (SP) is a tachykinin expressed by various cells in the nervous and immune systems. SP is predominantly released by neurons and exerts its biological and immunological effects through the neurokinin receptors, primarily the neurokinin-1 receptor (NK1R). SP is essential for maintaining ocular surface homeostasis, and its reduced levels in disorders like diabetic neuropathy disrupt the corneal tissue. It also plays an essential role in promoting corneal wound healing by promoting the migration of keratocytes. In this review, we briefly discuss the structure, expression, and function of SP and its principal receptor NK1R. In addition, SP induces pro-inflammatory effects through autocrine or paracrine action on the immune cells in various ocular surface pathologies, including dry eye disease, herpes simplex virus keratitis, and Pseudomonas keratitis. We provide an in-depth review of the pathogenic role of SP in various ocular surface diseases and several new approaches developed to counter the immune-mediated effects of SP either through modulating its production or blocking its target receptor.
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Erin N, Shurin GV, Baraldi JH, Shurin MR. Regulation of Carcinogenesis by Sensory Neurons and Neuromediators. Cancers (Basel) 2022; 14:cancers14092333. [PMID: 35565462 PMCID: PMC9102554 DOI: 10.3390/cancers14092333] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2022] [Revised: 04/26/2022] [Accepted: 05/05/2022] [Indexed: 12/12/2022] Open
Abstract
Simple Summary Sensory nerve fibers extensively innervate the entire body. They are the first to sense danger signals, including the ones coming from newly formed cancer cells. Various studies have demonstrated that the inactivation of sensory nerve fibers as well as the vagus nerve enhances tumor growth and spread in models including breast, pancreatic, and gastric cancer. On the other hand, there are also contradictory findings that show the opposite, namely that the inactivation of nerve fibers inhibits tumor growth. These discrepancies are likely caused by the stage and the level of aggressiveness of the tumor model used. Hence, further studies are required to determine the factors involved in neuro-immunological mechanisms of tumor growth and spread. Abstract Interactions between the immune system and the nervous system are crucial in maintaining homeostasis, and disturbances of these neuro-immune interactions may participate in carcinogenesis and metastasis. Nerve endings have been identified within solid tumors in humans and experimental animals. Although the involvement of the efferent sympathetic and parasympathetic innervation in carcinogenesis has been extensively investigated, the role of the afferent sensory neurons and the neuropeptides in tumor development, growth, and progression is recently appreciated. Similarly, current findings point to the significant role of Schwann cells as part of neuro-immune interactions. Hence, in this review, we mainly focus on local and systemic effects of sensory nerve activity as well as Schwann cells in carcinogenesis and metastasis. Specific denervation of vagal sensory nerve fibers, or vagotomy, in animal models, has been reported to markedly increase lung metastases of breast carcinoma as well as pancreatic and gastric tumor growth, with the formation of liver metastases demonstrating the protective role of vagal sensory fibers against cancer. Clinical studies have revealed that patients with gastric ulcers who have undergone a vagotomy have a greater risk of stomach, colorectal, biliary tract, and lung cancers. Protective effects of vagal activity have also been documented by epidemiological studies demonstrating that high vagal activity predicts longer survival rates in patients with colon, non-small cell lung, prostate, and breast cancers. However, several studies have reported that inhibition of sensory neuronal activity reduces the development of solid tumors, including prostate, gastric, pancreatic, head and neck, cervical, ovarian, and skin cancers. These contradictory findings are likely to be due to the post-nerve injury-induced activation of systemic sensory fibers, the level of aggressiveness of the tumor model used, and the local heterogeneity of sensory fibers. As the aggressiveness of the tumor model and the level of the inflammatory response increase, the protective role of sensory nerve fibers is apparent and might be mostly due to systemic alterations in the neuro-immune response. Hence, more insights into inductive and permissive mechanisms, such as systemic, cellular neuro-immunological mechanisms of carcinogenesis and metastasis formation, are needed to understand the role of sensory neurons in tumor growth and spread.
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Affiliation(s)
- Nuray Erin
- Department of Medical Pharmacology, Immunopharmacology, and Immuno-Oncology Unit, School of Medicine, Akdeniz University, 07070 Antalya, Turkey
- Correspondence:
| | - Galina V. Shurin
- Department of Pathology, University of Pittsburgh Medical Center and University of Pittsburgh Cancer Institute, Pittsburgh, 15213 PA, USA; (G.V.S.); (M.R.S.)
| | - James H. Baraldi
- Department of Neuroscience, University of Pittsburgh Medical Center and University of Pittsburgh Cancer Institute, Pittsburgh, 15213 PA, USA;
| | - Michael R. Shurin
- Department of Pathology, University of Pittsburgh Medical Center and University of Pittsburgh Cancer Institute, Pittsburgh, 15213 PA, USA; (G.V.S.); (M.R.S.)
- Department of Immunology, University of Pittsburgh Medical Center and University of Pittsburgh Cancer Institute, Pittsburgh, 15213 PA, USA
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10
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Inflammation-related molecules in tears of patients with chronic ocular pain and dry eye disease. Exp Eye Res 2022; 219:109057. [DOI: 10.1016/j.exer.2022.109057] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2022] [Revised: 03/21/2022] [Accepted: 03/24/2022] [Indexed: 12/28/2022]
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11
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Chen Y, Wang S, Alemi H, Dohlman T, Dana R. Immune regulation of the ocular surface. Exp Eye Res 2022; 218:109007. [PMID: 35257715 PMCID: PMC9050918 DOI: 10.1016/j.exer.2022.109007] [Citation(s) in RCA: 16] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2021] [Revised: 02/10/2022] [Accepted: 02/20/2022] [Indexed: 01/01/2023]
Abstract
Despite constant exposure to various environmental stimuli, the ocular surface remains intact and uninflamed while maintaining the transparency of the cornea and its visual function. This 'immune privilege' of the ocular surface is not simply a result of the physical barrier function of the mucosal lining but, more importantly, is actively maintained through a variety of immunoregulatory mechanisms that prevent the disruption of immune homeostasis. In this review, we focus on essential molecular and cellular players that promote immune quiescence in steady-state conditions and suppress inflammation in disease-states. Specifically, we examine the interactions between the ocular surface and its local draining lymphoid compartment, by encompassing the corneal epithelium, corneal nerves and cornea-resident myeloid cells, conjunctival goblet cells, and regulatory T cells (Treg) in the context of ocular surface autoimmune inflammation (dry eye disease) and alloimmunity (corneal transplantation). A better understanding of the immunoregulatory mechanisms will facilitate the development of novel, targeted immunomodulatory strategies for a broad range of ocular surface inflammatory disorders.
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Affiliation(s)
- Yihe Chen
- Schepens Eye Research Institute of Massachusetts Eye and Ear, Department of Ophthalmology, Harvard Medical School, Boston, MA, 02114, USA.
| | - Shudan Wang
- Schepens Eye Research Institute of Massachusetts Eye and Ear, Department of Ophthalmology, Harvard Medical School, Boston, MA, 02114, USA
| | - Hamid Alemi
- Schepens Eye Research Institute of Massachusetts Eye and Ear, Department of Ophthalmology, Harvard Medical School, Boston, MA, 02114, USA
| | - Thomas Dohlman
- Schepens Eye Research Institute of Massachusetts Eye and Ear, Department of Ophthalmology, Harvard Medical School, Boston, MA, 02114, USA
| | - Reza Dana
- Schepens Eye Research Institute of Massachusetts Eye and Ear, Department of Ophthalmology, Harvard Medical School, Boston, MA, 02114, USA
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12
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Tear film and ocular surface neuropeptides: Characteristics, synthesis, signaling and implications for ocular surface and systemic diseases. Exp Eye Res 2022; 218:108973. [PMID: 35149082 DOI: 10.1016/j.exer.2022.108973] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2021] [Revised: 12/14/2021] [Accepted: 02/01/2022] [Indexed: 01/13/2023]
Abstract
Ocular surface neuropeptides are vital molecules primarily involved in maintaining ocular surface integrity and homeostasis. They also serve as communication channels between the nervous system and the immune system, maintaining the homeostasis of the ocular surface. Tear film and ocular surface neuropeptides have a role in disease often due to abnormalities in their synthesis (either high or low production), signaling through defective receptors, or both. This creates imbalances in otherwise normal physiological processes. They have been observed to be altered in many ocular surface and systemic diseases including dry eye disease, ocular allergy, keratoconus, LASIK-induced dry eye, pterygium, neurotrophic keratitis, corneal graft rejection, microbial keratitis, headaches and diabetes. This review examines the characteristics of neuropeptides, their synthesis and their signaling through G-protein coupled receptors. The review also explores the types of neuropeptides within the tears and ocular surface, and how they change in ocular and systemic diseases.
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13
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Mucosal immunology of the ocular surface. Mucosal Immunol 2022; 15:1143-1157. [PMID: 36002743 PMCID: PMC9400566 DOI: 10.1038/s41385-022-00551-6] [Citation(s) in RCA: 26] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2021] [Revised: 05/26/2022] [Accepted: 06/10/2022] [Indexed: 02/04/2023]
Abstract
The eye is a sensory organ exposed to the environment and protected by a mucosal tissue barrier. While it shares a number of features with other mucosal tissues, the ocular mucosal system, composed of the conjunctiva, Meibomian glands, and lacrimal glands, is specialized to address the unique needs of (a) lubrication and (b) host defense of the ocular surface. Not surprisingly, most challenges, physical and immunological, to the homeostasis of the eye fall into those two categories. Dry eye, a dysfunction of the lacrimal glands and/or Meibomian glands, which can both cause, or arise from, sensory defects, including those caused by corneal herpes virus infection, serve as examples of these perturbations and will be discussed ahead. To preserve vision, dense neuronal and immune networks sense various stimuli and orchestrate responses, which must be tightly controlled to provide protection, while simultaneously minimizing collateral damage. All this happens against the backdrop of, and can be modified by, the microorganisms that colonize the ocular mucosa long term, or that are simply transient passengers introduced from the environment. This review will attempt to synthesize the existing knowledge and develop trends in the study of the unique mucosal and immune elements of the ocular surface.
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Lasagni Vitar RM, Bonelli F, Rama P, Ferrari G. Immunity and pain in the eye: focus on the ocular surface. Clin Exp Immunol 2021; 207:149-163. [PMID: 35020868 PMCID: PMC8982975 DOI: 10.1093/cei/uxab032] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2021] [Revised: 10/21/2021] [Accepted: 12/10/2021] [Indexed: 02/03/2023] Open
Abstract
Most ocular diseases are associated with pain. While pain has been generally considered a mere (deleterious) additional symptom, it is now emerging that it is a key modulator of innate/adaptive immunity. Because the cornea receives the highest nerve density of the entire body, it is an ideal site to demonstrate interactions between pain and the immune response. Indeed, most neuropeptides involved in pain generation are also potent regulators of innate and adaptive leukocyte physiology. On the other hand, most inflammatory cells can modulate the generation of ocular pain through release of specific mediators (cytokines, chemokines, growth factors, and lipid mediators). This review will discuss the reciprocal role(s) of ocular surface (and specifically: corneal) pain on the immune response of the eye. Finally, we will discuss the clinical implications of such reciprocal interactions in the context of highly prevalent corneal diseases.
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Affiliation(s)
- Romina Mayra Lasagni Vitar
- Cornea and Ocular Surface Disease Unit, Eye Repair Lab, IRCCS San Raffaele Scientific Institute, Milan, Italy
| | - Filippo Bonelli
- Cornea and Ocular Surface Disease Unit, Eye Repair Lab, IRCCS San Raffaele Scientific Institute, Milan, Italy
| | - Paolo Rama
- Cornea and Ocular Surface Disease Unit, Eye Repair Lab, IRCCS San Raffaele Scientific Institute, Milan, Italy
| | - Giulio Ferrari
- Cornea and Ocular Surface Disease Unit, Eye Repair Lab, IRCCS San Raffaele Scientific Institute, Milan, Italy,Correspondence: Giulio Ferrari, Cornea and Ocular Surface Unit, Eye Repair Lab, IRCCS San Raffaele Scientific Institute, Milan, Italy. E-mail:
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15
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Luna C, Quirce S, Aracil-Marco A, Belmonte C, Gallar J, Acosta MC. Unilateral Corneal Insult Also Alters Sensory Nerve Activity in the Contralateral Eye. Front Med (Lausanne) 2021; 8:767967. [PMID: 34869482 PMCID: PMC8634144 DOI: 10.3389/fmed.2021.767967] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2021] [Accepted: 10/11/2021] [Indexed: 01/21/2023] Open
Abstract
After the unilateral inflammation or nerve lesion of the ocular surface, the ipsilateral corneal sensory nerve activity is activated and sensitized, evoking ocular discomfort, irritation, and pain referred to the affected eye. Nonetheless, some patients with unilateral ocular inflammation, infection, or surgery also reported discomfort and pain in the contralateral eye. We explored the possibility that such altered sensations in the non-affected eye are due to the changes in their corneal sensory nerve activity in the contralateral, not directly affected eye. To test that hypothesis, we recorded the impulse activity of the corneal mechano- and polymodal nociceptor and cold thermoreceptor nerve terminals in both eyes of guinea pigs, subjected unilaterally to three different experimental conditions (UV-induced photokeratitis, microkeratome corneal surgery, and chronic tear deficiency caused by removal of the main lacrimal gland), and in eyes of naïve animals ex vivo. Overall, after unilateral eye damage, the corneal sensory nerve activity appeared to be also altered in the contralateral eye. Compared with the naïve guinea pigs, animals with unilateral UV-induced mild corneal inflammation, showed on both eyes an inhibition of the spontaneous and stimulus-evoked activity of cold thermoreceptors, and increased activity in nociceptors affecting both the ipsilateral and the contralateral eye. Unilateral microkeratome surgery affected the activity of nociceptors mostly, inducing sensitization in both eyes. The removal of the main lacrimal gland reduced tear volume and increased the cold thermoreceptor activity in both eyes. This is the first direct demonstration that unilateral corneal nerve lesion, especially ocular surface inflammation, functionally affects the activity of the different types of corneal sensory nerves in both the ipsilateral and contralateral eyes. The mechanisms underlying the contralateral affectation of sensory nerves remain to be determined, although available data support the involvement of neuroimmune interactions. The parallel alteration of nerve activity in contralateral eyes has two main implications: a) in the experimental design of both preclinical and clinical studies, where the contralateral eyes cannot be considered as a control; and, b) in the clinical practice, where clinicians must consider the convenience of treating both eyes of patients with unilateral ocular conditions to avoid pain and secondary undesirable effects in the fellow eye.
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Affiliation(s)
- Carolina Luna
- Instituto de Neurociencias, Universidad Miguel Hernández-CSIC, San Juan de Alicante, Spain
| | - Susana Quirce
- Instituto de Neurociencias, Universidad Miguel Hernández-CSIC, San Juan de Alicante, Spain
| | - Adolfo Aracil-Marco
- Instituto de Neurociencias, Universidad Miguel Hernández-CSIC, San Juan de Alicante, Spain
| | - Carlos Belmonte
- Instituto de Neurociencias, Universidad Miguel Hernández-CSIC, San Juan de Alicante, Spain
| | - Juana Gallar
- Instituto de Neurociencias, Universidad Miguel Hernández-CSIC, San Juan de Alicante, Spain.,Instituto de Investigación Sanitaria y Biomédica de Alicante, San Juan de Alicante, Spain
| | - M Carmen Acosta
- Instituto de Neurociencias, Universidad Miguel Hernández-CSIC, San Juan de Alicante, Spain
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16
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Chin JY, Lin MTY, Lee IXY, Mehta JS, Liu YC. Tear Neuromediator and Corneal Denervation Following SMILE. J Refract Surg 2021; 37:516-523. [PMID: 34388069 DOI: 10.3928/1081597x-20210423-01] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
PURPOSE To investigate the changes in tear neuromediators and corneal subbasal nerve plexus following small incision lenticule extraction (SMILE) and to study its association with different refractive power of corrections. METHODS Thirty patients were included for tear neuromediator analysis (40 eyes) and corneal nerve analysis using in vivo confocal microscopy scans (20 eyes). Tear samples were collected preoperatively and 1 week and 1, 3, 6, and 12 months postoperatively and analyzed for the substance P, calcitonin gene-related peptide (CGRP), and nerve growth factor (NGF) concentrations using the enzyme-linked immunosor-bent assay (ELISA). RESULTS Corneal nerve fiber density (CNFD), corneal nerve fiber length (CNFL), and corneal nerve branch density (CNBD) decreased significantly postoperatively, then gradually increased from 3 months onward, but did not recover to the baseline levels at 12 months. Tear substance P and CGRP levels remained stable over 12 months. Tear NGF levels demonstrated a small peak at 1 week before decreasing significantly compared to preoperative levels at 6 months (P = .03) and 12 months (P = .007). The 1-month reduction in CNFL, tear substance P, and CGRP concentrations were significantly correlated with the corrected spherical equivalent (SE) (r = 0.71 for CNFL; r = -0.33 to -0.52 at different time points for substance P and CGRP, respectively, all P < .05). Compared to the low to moderate myopia group, the high myopia group (corrected SE greater than -6.00 diopters) had a significantly greater decrease in CNFD, significantly higher tear substance P concentrations at 1 week, 1 month, and 6 months, and significantly higher tear CGRP concentrations at 1 and 6 months. CONCLUSIONS These results provide new insight into the neurobiological responses and their potential implications in corneal nerve damage and recovery after SMILE. High myopia treatment was associated with greater corneal denervation and neuroinflammation. [J Refract Surg. 2021;37(8):516-523.].
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17
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Baird PN, Machin H, Brown KD. Corneal supply and the use of technology to reduce its demand: A review. Clin Exp Ophthalmol 2021; 49:1078-1090. [PMID: 34310836 DOI: 10.1111/ceo.13978] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2021] [Revised: 07/13/2021] [Accepted: 07/14/2021] [Indexed: 11/26/2022]
Abstract
Recovery and access to end-of-life corneal tissue for corneal transplantation, training and research is globally maldistributed. The reasons for the maldistribution are complex and multifaceted, and not well defined or understood. Currently there are few solutions available to effectively address these issues. This review provides an overview of the system, key issues impacting recovery and allocation and emphasises how end-user ophthalmologists and researchers, with support from administrators and the wider sector, can assist in increasing access long-term through sustaining eye banks nationally and globally. We posit that prevention measures and improved surgical techniques, together with the development of novel therapies will play a significant role in reducing demand and enhance the equitable allocation of corneas.
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Affiliation(s)
- Paul N Baird
- Department of Surgery, Ophthalmology, University of Melbourne, Melbourne, Victoria, Australia
| | - Heather Machin
- Centre for Eye Research Australia, Royal Victorian Eye and Ear Hospital, Melbourne, Australia
- Lions Eye Donation Service, Melbourne, Australia
| | - Karl D Brown
- Centre for Eye Research Australia, Royal Victorian Eye and Ear Hospital, Melbourne, Australia
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18
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Niederkorn JY. "Corneal Nerves, CD11c + Dendritic Cells and Their Impact on Ocular Immune Privilege". Front Immunol 2021; 12:701935. [PMID: 34220866 PMCID: PMC8253307 DOI: 10.3389/fimmu.2021.701935] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2021] [Accepted: 05/19/2021] [Indexed: 11/19/2022] Open
Abstract
The eye and the brain have limited capacities for regeneration and as such, immune-mediated inflammation can produce devastating consequences in the form of neurodegenerative diseases of the central nervous system or blindness as a result of ocular inflammatory diseases such as uveitis. Accordingly, both the eye and the brain are designed to limit immune responses and inflammation - a condition known as "immune privilege". Immune privilege is sustained by physiological, anatomical, and regulatory processes that conspire to restrict both adaptive and innate immune responses.
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Affiliation(s)
- Jerry Y. Niederkorn
- Department of Ophthalmology, University of Texas Southwestern Medical Center, Dallas, TX, United States
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19
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Lasagni Vitar RM, Rama P, Ferrari G. The two-faced effects of nerves and neuropeptides in corneal diseases. Prog Retin Eye Res 2021; 86:100974. [PMID: 34098111 DOI: 10.1016/j.preteyeres.2021.100974] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2021] [Revised: 05/13/2021] [Accepted: 05/17/2021] [Indexed: 12/16/2022]
Abstract
Corneal nerves are instrumental to maintain cornea integrity through regulation of key physiological functions such as tear secretion, blink reflex, and neuropeptide turnover. Corneal nerve injury/stimulation can follow many insults including mechanical/chemical trauma, infections and surgeries. Nerve disruption initiates a process named neurogenic inflammation which leads to edema, pain, and recruitment and activation of leukocytes. Interestingly, leukocyte influx in the cornea can further damage nerves by releasing inflammatory mediators-including neuropeptides. The clinical outcome of neuroinflammation can be beneficial or detrimental to corneal integrity. On one side, it ensures prompt wound healing and prevents infections. On the other, prolonged and/or deranged neuroinflammation can permanently disrupt corneal integrity and impair vision. The cornea is an ideal site to study peripheral neuroinflammation and neurogenic inflammation since it receives the highest density of sensory nerves of the entire body. We will review the corneal nerve anatomy and neurochemistry, discuss the beneficial and detrimental effects of neurogenic inflammation in corneal wound healing, inflammatory processes, and pain. We will also examine the emerging remote impact of corneal nerve disruption on the trigeminal ganglion and the brain, highlighting the key role of neuropeptide Substance P. Finally, we will discuss the clinical relevance of such neuroinflammatory network in the context of severe and highly prevalent ocular diseases, including potential treatments.
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Affiliation(s)
- Romina Mayra Lasagni Vitar
- Cornea and Ocular Surface Disease Unit, Eye Repair Lab, IRCCS San Raffaele Scientific Institute, Milan, Italy
| | - Paolo Rama
- Cornea and Ocular Surface Disease Unit, Eye Repair Lab, IRCCS San Raffaele Scientific Institute, Milan, Italy
| | - Giulio Ferrari
- Cornea and Ocular Surface Disease Unit, Eye Repair Lab, IRCCS San Raffaele Scientific Institute, Milan, Italy.
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20
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Galletti JG, de Paiva CS. The ocular surface immune system through the eyes of aging. Ocul Surf 2021; 20:139-162. [PMID: 33621658 PMCID: PMC8113112 DOI: 10.1016/j.jtos.2021.02.007] [Citation(s) in RCA: 32] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2020] [Revised: 02/04/2021] [Accepted: 02/16/2021] [Indexed: 02/06/2023]
Abstract
Since the last century, advances in healthcare, housing, and education have led to an increase in life expectancy. Longevity is accompanied by a higher prevalence of age-related diseases, such as cancer, autoimmunity, diabetes, and infection, and part of this increase in disease incidence relates to the significant changes that aging brings about in the immune system. The eye is not spared by aging either, presenting with age-related disorders of its own, and interestingly, many of these diseases have immune pathophysiology. Being delicate organs that must be exposed to the environment in order to capture light, the eyes are endowed with a mucosal environment that protects them, the so-called ocular surface. As in other mucosal sites, immune responses at the ocular surface need to be swift and potent to eliminate threats but are at the same time tightly controlled to prevent excessive inflammation and bystander damage. This review will detail how aging affects the mucosal immune response of the ocular surface as a whole and how this process relates to the higher incidence of ocular surface disease in the elderly.
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Affiliation(s)
- Jeremias G Galletti
- Innate Immunity Laboratory, Institute of Experimental Medicine (IMEX), CONICET-National Academy of Medicine, Buenos Aires, Argentina.
| | - Cintia S de Paiva
- Ocular Surface Center, Cullen Eye Institute, Department of Ophthalmology, Baylor College of Medicine, Houston, TX, 77030, USA.
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21
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Mousa HM, Saban DR, Perez VL. The cornea IV immunology, infection, neovascularization, and surgery chapter 1: Corneal immunology. Exp Eye Res 2021; 205:108502. [PMID: 33607075 DOI: 10.1016/j.exer.2021.108502] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2020] [Revised: 02/07/2021] [Accepted: 02/10/2021] [Indexed: 12/27/2022]
Abstract
PURPOSE of Review: This review offers an informed and up-to-date insight on the immune profile of the cornea and the factors that govern the regulation of such a unique immune environment. SUMMARY The cornea is a unique tissue that performs the specialized task of allowing light to penetrate for visual interpretation. To accomplish this, the ocular surface requires a distinct immune environment that is achieved through unique structural, cellular and molecular factors. Not only must the cornea be able to fend off invasive infectious agents but also control the inflammatory response as to avoid collateral, and potentially blinding damage; particularly of post-mitotic cells such as the corneal endothelium. To combat infections, both innate and adaptive arms of the inflammatory immune response are at play in the cornea. Dendritic cells play a critical role in coordinating both these responses in order to fend off infections. On the other side of the spectrum, the ocular surface is also endowed with a variety of anatomic and physiologic components that aid in regulating the immune response to prevent excessive, potentially damaging, inflammation. This attenuation of the immune response is termed immune privilege. The balance between pro and anti-inflammatory reactions is key for preservation of the functional integrity of the cornea. RECENT FINDINGS The understanding of the molecular and cellular factors governing corneal immunology and its response to antigens is a growing field. Dendritic cells in the normal cornea play a crucial role in combating infections and coordinating the inflammatory arms of the immune response, particularly through coordination with T-helper cells. The role of neuropeptides is recently becoming more highlighted with different factors working on both sides of the inflammatory balance.
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Affiliation(s)
- Hazem M Mousa
- Foster Center for Ocular Immunology at Duke Eye Center, Duke University Medical Center, Durham, NC, USA
| | - Daniel R Saban
- Foster Center for Ocular Immunology at Duke Eye Center, Duke University Medical Center, Durham, NC, USA; Department of Immunology, Duke University School of Medicine, Durham, NC, USA
| | - Victor L Perez
- Foster Center for Ocular Immunology at Duke Eye Center, Duke University Medical Center, Durham, NC, USA.
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22
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Abstract
Clear vision is dependent on features that protect the anatomical integrity of the eye (cornea and sclera) and those that contribute to internal ocular homeostasis by conferring hemangiogenic (avascular tissues and antiangiogenic factors), lymphangiogenic (lack of draining lymphatics), and immunologic (tight junctions that form blood-ocular barriers, immunosuppressive cells, and modulators) privileges. The later examples are necessary components that enable the eye to maintain an immunosuppressive environment that responds to foreign invaders in a deviated manner, minimizing destructive inflammation that would impair vision. These conditions allowed for the observations made by Medawar, in 1948, of delayed rejection of allogenic tissue grafts in the anterior chamber of mouse eye and permit the sequestration of foreign invaders (eg, Toxoplasma gondii) within the retina of healthy individuals. Yet successful development of intraocular drugs (biologics and delivery devices) has been stymied by adverse ocular pathology, much of which is driven by immune pathways. The eye can be intolerant of foreign protein irrespective of delivery route, and endogenous ocular cells have remarkable plasticity when recruited to preserve visual function. This article provides a review of current understanding of ocular immunology and the potential role of immune mechanisms in pathology observed with intraocular drug delivery.
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Affiliation(s)
| | | | - Sharmila Masli
- 12259Boston University School of Medicine, Boston, MA, USA
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23
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Yanai R, Nishida T, Hatano M, Uchi SH, Yamada N, Kimura K. Role of the Neurokinin-1 Receptor in the Promotion of Corneal Epithelial Wound Healing by the Peptides FGLM-NH2 and SSSR in Neurotrophic Keratopathy. Invest Ophthalmol Vis Sci 2021; 61:29. [PMID: 32697304 PMCID: PMC7425742 DOI: 10.1167/iovs.61.8.29] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Purpose Neurotrophic keratopathy is a corneal epitheliopathy induced by trigeminal denervation that can be treated with eyedrops containing the neuropeptide substance P (or the peptide FGLM-NH2 derived therefrom) and insulin-like growth factor 1 (or the peptide SSSR derived therefrom). Here, we examine the mechanism by which substance P (or FGLM-NH2) promotes corneal epithelial wound healing in a mouse model of neurotrophic keratopathy. Methods The left eye of mice subjected to trigeminal nerve axotomy in the right eye served as a model of neurotrophic keratopathy. Corneal epithelial wound healing was monitored by fluorescein staining and slit-lamp examination. The distribution of substance P, neurokinin-1 receptor (NK-1R), and phosphorylated Akt was examined by immunohistofluorescence analysis. Cytokine and chemokine concentrations in intraocular fluid were measured with a multiplex assay. Results Topical administration of FGLM-NH2 and SSSR promoted corneal epithelial wound healing in the neurotrophic keratopathy model in a manner sensitive to the NK-1R antagonist L-733,060. Expression of substance P and NK-1R in the superficial layer of the corneal epithelium decreased and increased, respectively, in model mice compared with healthy mice. FGLM-NH2 and SSSR treatment suppressed the production of interleukin-1α, macrophage inflammatory protein 1α (MIP-1α) and MIP-1β induced by corneal epithelial injury in the model mice. It also increased the amount of phosphorylated Akt in the corneal epithelium during wound healing in a manner sensitive to prior L-733,060 administration. Conclusions The substance P–NK-1R axis promotes corneal epithelial wound healing in a neurotrophic keratopathy model in association with upregulation of Akt signaling and attenuation of changes in the cytokine-chemokine network.
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Yoon CH, Choi HJ, Kim MK. Corneal xenotransplantation: Where are we standing? Prog Retin Eye Res 2021; 80:100876. [PMID: 32755676 PMCID: PMC7396149 DOI: 10.1016/j.preteyeres.2020.100876] [Citation(s) in RCA: 29] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2020] [Revised: 05/23/2020] [Accepted: 06/04/2020] [Indexed: 02/08/2023]
Abstract
The search for alternatives to allotransplants is driven by the shortage of corneal donors and is demanding because of the limitations of the alternatives. Indeed, current progress in genetically engineered (GE) pigs, the introduction of gene-editing technology by clustered regularly interspaced short palindromic repeats (CRISPR)-Cas9, and advanced immunosuppressants have made xenotransplantation a possible option for a human trial. Porcine corneal xenotransplantation is considered applicable because the eye is regarded as an immune-privileged site. Furthermore, recent non-human primate studies have shown long-term survival of porcine xenotransplants in keratoplasty. Herein, corneal immune privilege is briefly introduced, and xenogeneic reactions are compared with allogeneic reactions in corneal transplantation. This review describes the current knowledge on special issues of xenotransplantation, xenogeneic rejection mechanisms, current immunosuppressive regimens of corneal xenotransplantation, preclinical efficacy and safety data of corneal xenotransplantation, and updates of the regulatory framework to conduct a clinical trial on corneal xenotransplantation. We also discuss barriers that might prevent xenotransplantation from becoming common practice, such as ethical dilemmas, public concerns on xenotransplantation, and the possible risk of xenozoonosis. Given that the legal definition of decellularized porcine cornea (DPC) lies somewhere between a medical device and a xenotransplant, the preclinical efficacy and clinical trial data using DPC are included. The review finally provides perspectives on the current standpoint of corneal xenotransplantation in the fields of regenerative medicine.
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Affiliation(s)
- Chang Ho Yoon
- Department of Ophthalmology, Seoul National University College of Medicine, Seoul, Republic of Korea; Laboratory of Ocular Regenerative Medicine and Immunology, Seoul Artificial Eye Center, Seoul National University Hospital Biomedical Research Institute, Seoul, Republic of Korea
| | - Hyuk Jin Choi
- Department of Ophthalmology, Seoul National University College of Medicine, Seoul, Republic of Korea; Laboratory of Ocular Regenerative Medicine and Immunology, Seoul Artificial Eye Center, Seoul National University Hospital Biomedical Research Institute, Seoul, Republic of Korea; Department of Ophthalmology, Seoul National University Hospital Healthcare System Gangnam Center, Seoul, Republic of Korea
| | - Mee Kum Kim
- Department of Ophthalmology, Seoul National University College of Medicine, Seoul, Republic of Korea; Laboratory of Ocular Regenerative Medicine and Immunology, Seoul Artificial Eye Center, Seoul National University Hospital Biomedical Research Institute, Seoul, Republic of Korea.
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Perez VL, Stern ME, Pflugfelder SC. Inflammatory basis for dry eye disease flares. Exp Eye Res 2020; 201:108294. [PMID: 33039458 PMCID: PMC7736538 DOI: 10.1016/j.exer.2020.108294] [Citation(s) in RCA: 68] [Impact Index Per Article: 17.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2020] [Revised: 10/02/2020] [Accepted: 10/05/2020] [Indexed: 12/15/2022]
Abstract
Most patients with chronic dry eye disease (DED) have episodic flares, which can be triggered by a variety of activities and environmental stresses. These flares are typically associated with rapid exacerbation of discomfort symptoms, followed by prolonged elevation of inflammation. In an acute flare, ocular surface inflammation begins with a nonspecific innate immune response, in some cases followed by a slower but more specific adaptive immune response. At the ocular surface, epithelial cells are central to the innate immune response, and we discuss their role in DED flares alongside the other core components. Epithelial cells and other cells of the innate response (neutrophils, monocytes, macrophages and dendritic cells) trigger flares in response to increased osmolarity, detected via pattern receptors on their cell surface. Ultimately, downstream signaling pathways activate innate and adaptive immune responses, with consequent inflammation and symptoms. In chronic DED, pathogenic T cells have infiltrated the ocular surface tissues. The established adaptive immune response is likely to lead to flare-ups at lower thresholds of stress, with inflammation maintained over a longer period. Increased understanding of the inflammatory cascades activated during a flare may guide management and improve outcomes.
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Affiliation(s)
- Victor L Perez
- Duke University School of Medicine, Durham, NC, United States
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26
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Singh RB, Marmalidou A, Amouzegar A, Chen Y, Dana R. Animal models of high-risk corneal transplantation: A comprehensive review. Exp Eye Res 2020; 198:108152. [PMID: 32721424 PMCID: PMC7508940 DOI: 10.1016/j.exer.2020.108152] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2020] [Revised: 07/05/2020] [Accepted: 07/15/2020] [Indexed: 12/16/2022]
Abstract
Over the past century, corneal transplantation has become the most commonly performed allogeneic solid tissue transplantation. Although more than 80% of the corneal transplantations have favorable outcomes, immune-mediated rejection continues to be the major cause of failure in well over 50% of graft recipients that have inflamed and vascularized host beds. Over the past two decades, the progress in our understanding of the immunological pathways that mediate graft rejection has aided in the development of novel therapeutic strategies. In order to successfully test the efficacy of these interventions, it is essential to model the immunological processes occurring as a consequence of corneal transplantation. Herein, we have comprehensively reviewed the established animal models used for replicating the immunopathological processes causing graft rejection in high-risk corneal transplantation settings. We have also discussed the practical and technical differences, as well as biological and immunological variations in different animal models.
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Affiliation(s)
- Rohan Bir Singh
- Schepens Eye Research Institute, Massachusetts Eye and Ear, Harvard Medical School, Boston, MA, USA
| | - Anna Marmalidou
- Schepens Eye Research Institute, Massachusetts Eye and Ear, Harvard Medical School, Boston, MA, USA
| | - Afsaneh Amouzegar
- Schepens Eye Research Institute, Massachusetts Eye and Ear, Harvard Medical School, Boston, MA, USA; Department of Internal Medicine, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
| | - Yihe Chen
- Schepens Eye Research Institute, Massachusetts Eye and Ear, Harvard Medical School, Boston, MA, USA
| | - Reza Dana
- Schepens Eye Research Institute, Massachusetts Eye and Ear, Harvard Medical School, Boston, MA, USA.
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27
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Jamali A, Kenyon B, Ortiz G, Abou-Slaybi A, Sendra VG, Harris DL, Hamrah P. Plasmacytoid dendritic cells in the eye. Prog Retin Eye Res 2020; 80:100877. [PMID: 32717378 DOI: 10.1016/j.preteyeres.2020.100877] [Citation(s) in RCA: 29] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2020] [Revised: 05/28/2020] [Accepted: 06/05/2020] [Indexed: 02/07/2023]
Abstract
Plasmacytoid dendritic cells (pDCs) are a unique subpopulation of immune cells, distinct from classical dendritic cells. pDCs are generated in the bone marrow and following development, they typically home to secondary lymphoid tissues. While peripheral tissues are generally devoid of pDCs during steady state, few tissues, including the lung, kidney, vagina, and in particular ocular tissues harbor resident pDCs. pDCs were originally appreciated for their potential to produce large quantities of type I interferons in viral immunity. Subsequent studies have now unraveled their pivotal role in mediating immune responses, in particular in the induction of tolerance. In this review, we summarize our current knowledge on pDCs in ocular tissues in both mice and humans, in particular in the cornea, limbus, conjunctiva, choroid, retina, and lacrimal gland. Further, we will review our current understanding on the significance of pDCs in ameliorating inflammatory responses during herpes simplex virus keratitis, sterile inflammation, and corneal transplantation. Moreover, we describe their novel and pivotal neuroprotective role, their key function in preserving corneal angiogenic privilege, as well as their potential application as a cell-based therapy for ocular diseases.
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Affiliation(s)
- Arsia Jamali
- Center for Translational Ocular Immunology, Tufts Medical Center, Tufts University School of Medicine, Boston, MA, USA; Department of Ophthalmology, Tufts Medical Center, Tufts University School of Medicine, Boston, MA, USA
| | - Brendan Kenyon
- Center for Translational Ocular Immunology, Tufts Medical Center, Tufts University School of Medicine, Boston, MA, USA; Program in Neuroscience, Graduate School of Biomedical Sciences, Tufts University, Boston, MA, USA
| | - Gustavo Ortiz
- Center for Translational Ocular Immunology, Tufts Medical Center, Tufts University School of Medicine, Boston, MA, USA; Department of Ophthalmology, Tufts Medical Center, Tufts University School of Medicine, Boston, MA, USA
| | - Abdo Abou-Slaybi
- Center for Translational Ocular Immunology, Tufts Medical Center, Tufts University School of Medicine, Boston, MA, USA; Program in Immunology, Graduate School of Biomedical Sciences, Tufts University, Boston, MA, USA
| | - Victor G Sendra
- Center for Translational Ocular Immunology, Tufts Medical Center, Tufts University School of Medicine, Boston, MA, USA; Department of Ophthalmology, Tufts Medical Center, Tufts University School of Medicine, Boston, MA, USA
| | - Deshea L Harris
- Center for Translational Ocular Immunology, Tufts Medical Center, Tufts University School of Medicine, Boston, MA, USA; Department of Ophthalmology, Tufts Medical Center, Tufts University School of Medicine, Boston, MA, USA
| | - Pedram Hamrah
- Center for Translational Ocular Immunology, Tufts Medical Center, Tufts University School of Medicine, Boston, MA, USA; Department of Ophthalmology, Tufts Medical Center, Tufts University School of Medicine, Boston, MA, USA; Program in Neuroscience, Graduate School of Biomedical Sciences, Tufts University, Boston, MA, USA; Program in Immunology, Graduate School of Biomedical Sciences, Tufts University, Boston, MA, USA; Cornea Service, Tufts New England Eye Center, Boston, MA, USA.
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28
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Abstract
Human corneal transplantation (keratoplasty) is typically considered to have superior short- and long-term outcomes and lower requirement for immunosuppression compared to solid organ transplants because of the inherent immune privilege and tolerogenic mechanisms associated with the anterior segment of the eye. However, in a substantial proportion of corneal transplants, the rates of acute rejection and/or graft failure are comparable to or greater than those of the commonly transplanted solid organs. Critically, while registry data and observational studies have helped to identify factors that are associated with increased risk of corneal transplant failure, the extent to which these risk factors operate through enhancing immune-mediated rejection is less clear. In this overview, we summarize a range of important recent clinical and basic insights related to high-risk corneal transplantation, the factors associated with graft failure, and the immunological basis of corneal allograft rejection. We highlight critical research areas from which continued progress is likely to drive improvements in the long-term survival of high-risk corneal transplants. These include further development and clinical testing of predictive risk scores and assays; greater use of multicenter clinical trials to optimize immunosuppressive therapy in high-risk recipients and robust clinical translation of novel, mechanistically-targeted immunomodulatory and regenerative therapies that are emerging from basic science laboratories. We also emphasize the relative lack of knowledge regarding transplant outcomes for infection-related corneal diseases that are common in the developing world and the potential for greater cross-pollination and synergy between corneal and solid organ transplant research communities.
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29
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Das S, Gordián-Vélez WJ, Ledebur HC, Mourkioti F, Rompolas P, Chen HI, Serruya MD, Cullen DK. Innervation: the missing link for biofabricated tissues and organs. NPJ Regen Med 2020; 5:11. [PMID: 32550009 PMCID: PMC7275031 DOI: 10.1038/s41536-020-0096-1] [Citation(s) in RCA: 51] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2019] [Accepted: 04/29/2020] [Indexed: 12/15/2022] Open
Abstract
Innervation plays a pivotal role as a driver of tissue and organ development as well as a means for their functional control and modulation. Therefore, innervation should be carefully considered throughout the process of biofabrication of engineered tissues and organs. Unfortunately, innervation has generally been overlooked in most non-neural tissue engineering applications, in part due to the intrinsic complexity of building organs containing heterogeneous native cell types and structures. To achieve proper innervation of engineered tissues and organs, specific host axon populations typically need to be precisely driven to appropriate location(s) within the construct, often over long distances. As such, neural tissue engineering and/or axon guidance strategies should be a necessary adjunct to most organogenesis endeavors across multiple tissue and organ systems. To address this challenge, our team is actively building axon-based "living scaffolds" that may physically wire in during organ development in bioreactors and/or serve as a substrate to effectively drive targeted long-distance growth and integration of host axons after implantation. This article reviews the neuroanatomy and the role of innervation in the functional regulation of cardiac, skeletal, and smooth muscle tissue and highlights potential strategies to promote innervation of biofabricated engineered muscles, as well as the use of "living scaffolds" in this endeavor for both in vitro and in vivo applications. We assert that innervation should be included as a necessary component for tissue and organ biofabrication, and that strategies to orchestrate host axonal integration are advantageous to ensure proper function, tolerance, assimilation, and bio-regulation with the recipient post-implant.
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Affiliation(s)
- Suradip Das
- Center for Brain Injury & Repair, Department of Neurosurgery, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA USA
- Center for Neurotrauma, Neurodegeneration & Restoration, Corporal Michael J. Crescenz Veterans Affairs Medical Center, Philadelphia, PA USA
| | - Wisberty J. Gordián-Vélez
- Center for Brain Injury & Repair, Department of Neurosurgery, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA USA
- Center for Neurotrauma, Neurodegeneration & Restoration, Corporal Michael J. Crescenz Veterans Affairs Medical Center, Philadelphia, PA USA
- Department of Bioengineering, School of Engineering and Applied Science, University of Pennsylvania, Philadelphia, PA USA
| | | | - Foteini Mourkioti
- Department of Orthopedic Surgery, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA USA
- Department of Cell and Developmental Biology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA USA
| | - Panteleimon Rompolas
- Department of Dermatology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA USA
| | - H. Isaac Chen
- Center for Brain Injury & Repair, Department of Neurosurgery, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA USA
- Center for Neurotrauma, Neurodegeneration & Restoration, Corporal Michael J. Crescenz Veterans Affairs Medical Center, Philadelphia, PA USA
| | - Mijail D. Serruya
- Center for Neurotrauma, Neurodegeneration & Restoration, Corporal Michael J. Crescenz Veterans Affairs Medical Center, Philadelphia, PA USA
- Department of Neurology, Thomas Jefferson University, Philadelphia, PA USA
| | - D. Kacy Cullen
- Center for Brain Injury & Repair, Department of Neurosurgery, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA USA
- Center for Neurotrauma, Neurodegeneration & Restoration, Corporal Michael J. Crescenz Veterans Affairs Medical Center, Philadelphia, PA USA
- Department of Bioengineering, School of Engineering and Applied Science, University of Pennsylvania, Philadelphia, PA USA
- Axonova Medical, LLC., Philadelphia, PA USA
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Neelam S, Niederkorn JY. Corneal Nerve Ablation Abolishes Ocular Immune Privilege by Downregulating CD103 on T Regulatory Cells. Invest Ophthalmol Vis Sci 2020; 61:25. [PMID: 32305043 PMCID: PMC7401639 DOI: 10.1167/iovs.61.4.25] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2020] [Accepted: 02/28/2020] [Indexed: 11/24/2022] Open
Abstract
Purpose Severing corneal nerves during orthotopic corneal transplantation elicits the elaboration of the neuropeptide substance P (SP), which induces the generation of CD11c+ contrasuppressor (CS) cells. CS cells disable T regulatory cells (Tregs) that are induced when antigens enter the anterior chamber (AC), either by direct injection or by orthotopic corneal transplantation. This study examined the crucial cell surface molecules on Tregs that are adversely affected by CS cells that are generated by severing corneal nerves. Methods CS cells were induced by producing shallow 2.0-mm circular incisions in the corneal epithelium in BALB/c mice. CD8+ Tregs were generated by injecting ovalbumin into the AC. The effects of CS cells and SP on the expression and function of two cell surface molecules (CD103 and the receptor of interferon-γ) that are crucial for the induction and function of CD8+ Tregs were analyzed. Results SP converted CD11c+, but not CD11c- , dendritic cells (DCs) to CS cells. Severing corneal nerves resulted in a 66% reduction in the expression of CD103 on CD8+ AC-associated immune deviation (ACAID) Tregs, and a 50% reduction in the interferon-γ receptor (IFN-γR). These effects could be mimicked in vitro by coculturing CS cells with CD8+ ACAID Tregs. Conclusions The elaboration of SP in response to corneal nerve ablation converts CD11c+ DCs to CS cells. CS cells disable CD8+ ACAID Tregs by downregulating two crucial cell surface molecules, CD103 and IFN-γR, by an SP-dependent pathway. Blocking this pathway may provide a means of restoring ocular immune privilege in corneas subjected to corneal nerve injury.
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Affiliation(s)
- Sudha Neelam
- Department of Ophthalmology, University of Texas Southwestern Medical Center, Dallas, Texas, United States
| | - Jerry Y. Niederkorn
- Department of Ophthalmology, University of Texas Southwestern Medical Center, Dallas, Texas, United States
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31
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Giannaccare G, Bernabei F, Pellegrini M, Guaraldi F, Turchi F, Torrazza C, Senni C, Scotto R, Sindaco D, Di Cello L, Versura P, Scorcia V, Traverso CE, Vagge A. Bilateral morphometric analysis of corneal sub-basal nerve plexus in patients undergoing unilateral cataract surgery: a preliminary in vivo confocal microscopy study. Br J Ophthalmol 2020; 105:174-179. [PMID: 32245849 DOI: 10.1136/bjophthalmol-2019-315449] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2019] [Revised: 03/02/2020] [Accepted: 03/20/2020] [Indexed: 11/03/2022]
Abstract
AIMS To evaluate bilateral morphometric changes of corneal sub-basal nerve plexus (CSNP) occurring after unilateral cataract surgery by in vivo confocal microscopy (IVCM) images analysed with automated software. METHODS IVCM was performed before (V0) and 1 month after surgery (V1) in both operated eyes (OEs) and unoperated eyes (UEs) of 30 patients. Thirty age and sex-matched subjects acted as controls. Corneal nerve fibre density (CNFD), corneal nerve branch density (CNBD), corneal nerve fibre length (CNFL), corneal nerve total branch density (CTBD), corneal nerve fibre area (CNFA), corneal nerve fibre width, corneal nerve fractal dimension (CNFrD) and dendritic cells density were calculated. RESULTS Mean CNFD, CNBD, CNFL, CTBD, CNFA and CNFrD significantly decreased at V1 versus V0 in both eyes (respectively, 15.35±7.00 vs 21.21±6.56 n/mm2 in OEs and 20.11±6.69 vs 23.20±7.26 in UEs; 13.57±12.16 vs 26.79±16.91 n/mm2 in OEs and 24.28±14.88 vs 29.76±15.25 in UEs; 9.67±3.44 mm/mm2 vs 13.49±3.42 in OEs and 12.53±3.60 vs 14.02±3.82 in UEs; 22.81±18.77 vs 42.25±24.64 n/mm2 in OEs and 38.06±20.52 vs 43.93±22.27 in UEs; 0.0040±0.0021 vs 0.0058±0.0020 mm2/mm2 in OEs and 0.0049±0.0016 vs 0.0057±0.0019 in UEs; 1.418±0.058 vs 1.470±0.037 in OEs and 1.466±0.040 vs 1.477±0.036 in UEs; always p<0.049). CONCLUSION Patients undergoing cataract surgery exhibit bilateral alterations of CSNP. This finding could have broad implications in the setting of sequential cataract surgery.
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Affiliation(s)
- Giuseppe Giannaccare
- Department of Ophthalmology, University Magna Græcia of Catanzaro, Catanzaro, Italy
| | - Federico Bernabei
- Ophthalmology Unit, S.Orsola-Malpighi University Hospital, University of Bologna, Bologna, Italy
| | - Marco Pellegrini
- Ophthalmology Unit, S.Orsola-Malpighi University Hospital, University of Bologna, Bologna, Italy
| | - Fabio Guaraldi
- Ophthalmology Unit, S.Orsola-Malpighi University Hospital, University of Bologna, Bologna, Italy
| | - Federica Turchi
- Ophthalmology Unit, S.Orsola-Malpighi University Hospital, University of Bologna, Bologna, Italy
| | - Carlo Torrazza
- Ophthalmology Unit, S.Orsola-Malpighi University Hospital, University of Bologna, Bologna, Italy
| | - Carlotta Senni
- Ophthalmology Unit, S.Orsola-Malpighi University Hospital, University of Bologna, Bologna, Italy
| | - Riccardo Scotto
- Department of Neuroscience Rehabilitation Ophthalmology Genetics and Maternal and Child Health Genova, University of Genoa, Genova, Italy
| | - Daniele Sindaco
- Department of Neuroscience Rehabilitation Ophthalmology Genetics and Maternal and Child Health Genova, University of Genoa, Genova, Italy
| | - Luca Di Cello
- Department of Neuroscience Rehabilitation Ophthalmology Genetics and Maternal and Child Health Genova, University of Genoa, Genova, Italy
| | - Piera Versura
- Ophthalmology Unit, S.Orsola-Malpighi University Hospital, University of Bologna, Bologna, Italy
| | - Vincenzo Scorcia
- Department of Ophthalmology, University Magna Græcia of Catanzaro, Catanzaro, Italy
| | - Carlo E Traverso
- Di.N.O.G, Centro di Ricerca Clinica e Laboratorio per il Glaucoma e la Cornea, Eye Clinic, Genova, Italy
| | - Aldo Vagge
- Department of Neuroscience Rehabilitation Ophthalmology Genetics and Maternal and Child Health Genova, University of Genoa, Genova, Italy
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32
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Liu L, Dana R, Yin J. Sensory neurons directly promote angiogenesis in response to inflammation via substance P signaling. FASEB J 2020; 34:6229-6243. [PMID: 32162744 DOI: 10.1096/fj.201903236r] [Citation(s) in RCA: 32] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2019] [Revised: 02/26/2020] [Accepted: 02/27/2020] [Indexed: 12/14/2022]
Abstract
Blood vessels and nerves travel together to supply most tissues in the body. However, there is a knowledge gap in the mechanisms underlying the direct regulation of angiogenesis by nerves. In the current study, we examined the regulation of angiogenesis by sensory nerves in response to inflammation using the cornea, a normally avascular and densely innervated ocular tissue, as a model. We used desiccating stress as an inflammatory stimulus in vivo and found that sub-basal and epithelial nerve densities in the cornea were reduced in dry eye disease (DED). We established a co-culture system of trigeminal ganglion sensory neurons and vascular endothelial cells (VEC) and found that neurons isolated from mice with DED directly promoted VEC proliferation and tube formation compared with normal controls. In addition, these neurons expressed and secreted higher levels of substance P (SP), a proinflammatory neuropeptide. SP potently promoted VEC activation in vitro and blockade of SP signaling with spantide I, an antagonist of SP receptor Neurokinin-1, significantly reduced corneal neovascularization in vivo. Spantide I and siRNA knockdown of SP abolished the promotion of VEC activation by DED neurons in vitro. Taken together, our data suggested that sensory neurons directly promote angiogenesis via SP signaling in response to inflammation in the cornea.
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Affiliation(s)
- Lingjia Liu
- Schepens Eye Research Institute of Massachusetts Eye and Ear, Harvard Medical School, Boston, MA, USA.,School of Medicine, Nankai University, Tianjin, China
| | - Reza Dana
- Schepens Eye Research Institute of Massachusetts Eye and Ear, Harvard Medical School, Boston, MA, USA
| | - Jia Yin
- Schepens Eye Research Institute of Massachusetts Eye and Ear, Harvard Medical School, Boston, MA, USA
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33
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Kinetics of Tear Fluid Proteins after Endothelial Keratoplasty and Predictive Factors for Recovery from Corneal Haze. J Clin Med 2019; 9:jcm9010063. [PMID: 31888042 PMCID: PMC7019256 DOI: 10.3390/jcm9010063] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2019] [Revised: 12/10/2019] [Accepted: 12/21/2019] [Indexed: 12/18/2022] Open
Abstract
Endothelial keratoplasty (EK) is less invasive with faster recovery as compared to conventional penetrating keratoplasty, however, it relies on the clarity of the host corneal stroma. Corneal transplantation involves the induction of immune tolerance for allogeneic tissues as well as the corneal wound healing process, in which coordinated interactions between cytokines and growth factors are critical. In this study, we profiled the expression of 51 soluble factors in the tear fluid over the course of EK and have provided evidence of dynamic changes in cytokine expression in the ipsilateral and contralateral eyes. Cluster analyses classified the cytokine expression kinetics into five groups. Group 1 proteins included TGF-b1, IL-1b, and innate proinflammatory cytokines, which bilaterally increased after surgery, despite the use of topical corticosteroid in the transplanted eyes. Local corticosteroids suppressed cytokines involved in adaptive immunity in the transplanted eyes but not in the contralateral eyes. We found tear protein expression at baseline and one week post-surgery to be a potential predictive biomarker of delayed recovery after EK in terms of the corneal haze and visual acuity. Furthermore, Group 1 tear proteins were most associated with persistent corneal haze pre-surgery as well as visual acuity at one month-post transplant.
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34
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Niederkorn JY. The Eye Sees Eye to Eye With the Immune System: The 2019 Proctor Lecture. Invest Ophthalmol Vis Sci 2019; 60:4489-4495. [PMID: 31661549 PMCID: PMC6819053 DOI: 10.1167/iovs.19-28632] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023] Open
Affiliation(s)
- Jerry Y. Niederkorn
- Department of Ophthalmology, University of Texas Southwestern Medical Center, Dallas, Texas, United States
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35
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Jiao H, Naranjo Golborne C, Dando SJ, McMenamin PG, Downie LE, Chinnery HR. Topographical and Morphological Differences of Corneal Dendritic Cells during Steady State and Inflammation. Ocul Immunol Inflamm 2019; 28:898-907. [PMID: 31429614 DOI: 10.1080/09273948.2019.1646775] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
PURPOSE We report novel differences in mouse corneal DC morphology and density during local and systemic inflammation. METHODS Local inflammation was induced by topical application of saline or TLR9 agonist CpG-ODN on abraded C57BL6J mouse corneas. Systemic inflammation was induced by intraperitoneal injection of lipopolysaccharide (LPS) in CD11c-YFP mice. Corneal epithelial DCs from uninjured, injured and contralateral eyes were analysed by confocal microscopy. RESULTS Following local CpG delivery on the injured cornea, the DC density and size increased in both central and peripheral regions. Contralateral uninjured eyes displayed enlarged DC morphology in the central cornea compared to naïve cohorts. After systemic LPS, the size of DCs in the central cornea was lower at 2 hours, returning to baseline after 24 hours. CONCLUSIONS Corneal DCs respond differently in terms of shape and distribution during local and systemic inflammation. These features can serve as in vivo indicators in ocular and systemic diseases.
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Affiliation(s)
- Haihan Jiao
- Department of Optometry and Vision Sciences, The University of Melbourne , Melbourne, Australia
| | - Cecilia Naranjo Golborne
- Monash Genome Modification Platform, Faculty of Medicine, Nursing and Health Sciences, Monash University , Melbourne, Australia
| | - Samantha J Dando
- School of Biomedical Sciences and Institute of Health and Biomedical Innovation, Queensland University of Technology , Brisbane, Australia.,Monash Biomedicine Discovery Institute and Department of Anatomy & Developmental Biology, Faculty of Medicine, Nursing and Health Sciences, Monash University , Melbourne, Australia
| | - Paul G McMenamin
- Monash Biomedicine Discovery Institute and Department of Anatomy & Developmental Biology, Faculty of Medicine, Nursing and Health Sciences, Monash University , Melbourne, Australia
| | - Laura E Downie
- Department of Optometry and Vision Sciences, The University of Melbourne , Melbourne, Australia
| | - Holly R Chinnery
- Department of Optometry and Vision Sciences, The University of Melbourne , Melbourne, Australia
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Royer DJ, Echegaray-Mendez J, Lin L, Gmyrek GB, Mathew R, Saban DR, Perez VL, Carr DJ. Complement and CD4 + T cells drive context-specific corneal sensory neuropathy. eLife 2019; 8:48378. [PMID: 31414985 PMCID: PMC6783265 DOI: 10.7554/elife.48378] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2019] [Accepted: 08/15/2019] [Indexed: 12/18/2022] Open
Abstract
Whether complement dysregulation directly contributes to the pathogenesis of peripheral nervous system diseases, including sensory neuropathies, is unclear. We addressed this important question in a mouse model of ocular HSV-1 infection, where sensory nerve damage is a common clinical problem. Through genetic and pharmacologic targeting, we uncovered a central role for C3 in sensory nerve damage at the morphological and functional levels. Interestingly, CD4 T cells were central in facilitating this complement-mediated damage. This same C3/CD4 T cell axis triggered corneal sensory nerve damage in a mouse model of ocular graft-versus-host disease (GVHD). However, this was not the case in a T-dependent allergic eye disease (AED) model, suggesting that this inflammatory neuroimmune pathology is specific to certain disease etiologies. Collectively, these findings uncover a central role for complement in CD4 T cell-dependent corneal nerve damage in multiple disease settings and indicate the possibility for complement-targeted therapeutics to mitigate sensory neuropathies.
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Affiliation(s)
- Derek J Royer
- Department of Ophthalmology, Duke University Medical Center, Durham, United States.,Department of Ophthalmology, University of Oklahoma Health Sciences Center, Oklahoma City, United States
| | | | - Liwen Lin
- Department of Ophthalmology, Duke University Medical Center, Durham, United States
| | - Grzegorz B Gmyrek
- Department of Ophthalmology, University of Oklahoma Health Sciences Center, Oklahoma City, United States
| | - Rose Mathew
- Department of Ophthalmology, Duke University Medical Center, Durham, United States
| | - Daniel R Saban
- Department of Ophthalmology, Duke University Medical Center, Durham, United States.,Department of Immunology, Duke University Medical Center, Durham, United States
| | - Victor L Perez
- Department of Ophthalmology, Duke University Medical Center, Durham, United States
| | - Daniel Jj Carr
- Department of Ophthalmology, University of Oklahoma Health Sciences Center, Oklahoma City, United States.,Department of Microbiology and Immunology, University of Oklahoma Health Sciences Center, Oklahoma City, United States
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37
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Gross J, Willimsky E, Wegener AR, Kronschläger M, Schönfeld CL, Holz FG, Meyer LM. Ultraviolet Radiation Exposure of One Eye Stimulates Sympathizing Expression of Neurokinin-1 Receptor but Not Monocyte Chemoattractant Protein-1 in the Partner Eye. Ophthalmic Res 2019; 63:59-71. [PMID: 31408874 DOI: 10.1159/000501320] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2019] [Accepted: 05/28/2019] [Indexed: 11/19/2022]
Abstract
PURPOSE To investigate the influence of unilateral ultraviolet radiation (UVR) exposure on the unexposed, partner eye in vivo. To characterize the immunological cross-talk between the eyes and verify a sympathizing reaction of the partner eye via a neurokinin-dependent signaling pathway of substance P and its neurokinin-1 receptor (NKR-1) and/or monocyte chemoattractant protein-1 (MCP-1). METHODS C57BL/6 mice were unilaterally exposed in vivo to UVR-B to a 5-fold cataract threshold equivalent dose of 14.5 kJ/m2 with a UV irradiation Bio-Spectra system. The unexposed contralateral eye was completely shielded during irradiation. After 3 and 7 days post exposure, eyes were stained with fluorescence-coupled antibody for substance P NKR-1. The same was performed in control animals receiving only anesthesia but no UVR-B exposure. NKR-1 and MCP-1 levels in ocular tissue lysates were quantified by enzyme-linked immunosorbent assay. RESULTS UVR-B induces NKR-1 upregulation after 3 and 7 days in the exposed and in the unexposed, contralateral mouse eye. NKR-1 protein level was upregulated in the exposed and contralateral iris/ciliary body complex, choroidea and in the contralateral retina as well as in the exposed cornea. MCP-1 levels were elevated in the exposed cornea, iris/ciliary body complex, and aqueous humor but not in contralateral ocular tissues. CONCLUSIONS UVR-B exposure triggers NKR-1 upregulation not only in the exposed but also in the unexposed, partner eye in various ocular tissues. Following UVR-B exposure, MCP-1 protein levels are upregulated in the exposed eye, but the contralateral side remains unaffected.
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Affiliation(s)
- Janine Gross
- Department of Ophthalmology, University of Bonn, Bonn, Germany,
| | - Eva Willimsky
- Department of Ophthalmology, University of Bonn, Bonn, Germany
| | | | | | - Carl-Ludwig Schönfeld
- Herzog Carl Theodor Eye Clinic, Munich, Germany.,Department of Ophthalomology, Ludwig-Maximilians University, Munich, Germany
| | - Frank G Holz
- Department of Ophthalmology, University of Bonn, Bonn, Germany
| | - Linda M Meyer
- Department of Ophthalmology, University of Bonn, Bonn, Germany.,Herzog Carl Theodor Eye Clinic, Munich, Germany
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38
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Zhao HX, Li XY, Guan WY, Han XT. Impact of co-blocking the costimulatory signals on immune-related genes after high-risk rabbit corneal allograft using 2nd-generation DNA sequencing technology. Genet Mol Biol 2019; 42:472-479. [PMID: 31323080 PMCID: PMC6726163 DOI: 10.1590/1678-4685-gmb-2018-0150] [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: 05/31/2018] [Accepted: 10/15/2018] [Indexed: 11/22/2022] Open
Abstract
The aim of this study was to evaluate the impact and mechanism of co-blocking of costimulatory signals CD28-B7-CD40-CD40L during immune allograft rejection. Forty-eight recipient rabbits were prepared as a high-risk corneal allograft model. After surgery, the animals were randomly divided into: control group, MR1 group, anti-B7 group, and co-blocking group (n=12, each group). Subconjunctival injection was first performed on the allograft surgery day until post-surgery day five. Four weeks later, or when immune rejection occurred, the cornea was sampled to detect and analyze the gene spectrum. The survival time in the co-blocking group was significantly longer than that in the other three groups (p < 0.05). Gene expression analysis revealed that the expression of genes associated with immune rejection, interleukin (IL)-1α, IL-1β, intercellular cell adhesion molecule-1, and IL-2 was down-regulated in the co-blocking group, while IL-10 was up-regulated, but the changes in nuclear factor-κB and interferon-γ were not significant. In conclusion, the co-blocking of costimulatory signals can significantly reduce genes that promote corneal allograft rejection. The inhibition of corneal allograft rejection gene expression was significantly enhanced. These gene expression results can explain the conclusion of previous work at the genetic level.
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Affiliation(s)
- Hai-Xia Zhao
- Center of Myopia, The Affiliated Hospital of Inner Mongolia Medical University, Hohhot, China
| | - Xin-Yu Li
- Center of Myopia, The Affiliated Hospital of Inner Mongolia Medical University, Hohhot, China
| | - Wen-Ying Guan
- Center of Myopia, The Affiliated Hospital of Inner Mongolia Medical University, Hohhot, China
| | - Xiao-Tong Han
- Center of Myopia, The Affiliated Hospital of Inner Mongolia Medical University, Hohhot, China
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Hos D, Matthaei M, Bock F, Maruyama K, Notara M, Clahsen T, Hou Y, Le VNH, Salabarria AC, Horstmann J, Bachmann BO, Cursiefen C. Immune reactions after modern lamellar (DALK, DSAEK, DMEK) versus conventional penetrating corneal transplantation. Prog Retin Eye Res 2019; 73:100768. [PMID: 31279005 DOI: 10.1016/j.preteyeres.2019.07.001] [Citation(s) in RCA: 146] [Impact Index Per Article: 29.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2018] [Revised: 07/01/2019] [Accepted: 07/02/2019] [Indexed: 12/12/2022]
Abstract
In the past decade, novel lamellar keratoplasty techniques such as Deep Anterior Lamellar Keratoplasty (DALK) for anterior keratoplasty and Descemet stripping automated endothelial keratoplasty (DSAEK)/Descemet membrane endothelial keratoplasty (DMEK) for posterior keratoplasty have been developed. DALK eliminates the possibility of endothelial allograft rejection, which is the main reason for graft failure after penetrating keratoplasty (PK). Compared to PK, the risk of endothelial graft rejection is significantly reduced after DSAEK/DMEK. Thus, with modern lamellar techniques, the clinical problem of endothelial graft rejection seems to be nearly solved in the low-risk situation. However, even with lamellar grafts there are epithelial, subepithelial and stromal immune reactions in DALK and endothelial immune reactions in DSAEK/DMEK, and not all keratoplasties can be performed in a lamellar fashion. Therefore, endothelial graft rejection in PK is still highly relevant, especially in the "high-risk" setting, where the cornea's (lymph)angiogenic and immune privilege is lost due to severe inflammation and pathological neovascularization. For these eyes, currently available treatment options are still unsatisfactory. In this review, we will describe currently used keratoplasty techniques, namely PK, DALK, DSAEK, and DMEK. We will summarize their indications, provide surgical descriptions, and comment on their complications and outcomes. Furthermore, we will give an overview on corneal transplant immunology. A specific focus will be placed on endothelial graft rejection and we will report on its incidence, clinical presentation, and current/future treatment and prevention options. Finally, we will speculate how the field of keratoplasty and prevention of corneal allograft rejection will develop in the future.
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Affiliation(s)
- Deniz Hos
- Department of Ophthalmology, University of Cologne, Cologne, Germany; Center for Molecular Medicine Cologne (CMMC), University of Cologne, Cologne, Germany
| | - Mario Matthaei
- Department of Ophthalmology, University of Cologne, Cologne, Germany
| | - Felix Bock
- Department of Ophthalmology, University of Cologne, Cologne, Germany; Center for Molecular Medicine Cologne (CMMC), University of Cologne, Cologne, Germany
| | - Kazuichi Maruyama
- Department of Innovative Visual Science, Graduate School of Medicine, Osaka University, Japan
| | - Maria Notara
- Department of Ophthalmology, University of Cologne, Cologne, Germany; Center for Molecular Medicine Cologne (CMMC), University of Cologne, Cologne, Germany
| | - Thomas Clahsen
- Department of Ophthalmology, University of Cologne, Cologne, Germany
| | - Yanhong Hou
- Department of Ophthalmology, University of Cologne, Cologne, Germany
| | - Viet Nhat Hung Le
- Department of Ophthalmology, University of Cologne, Cologne, Germany; Department of Ophthalmology, Hue College of Medicine and Pharmacy, Hue University, Viet Nam
| | | | - Jens Horstmann
- Department of Ophthalmology, University of Cologne, Cologne, Germany
| | - Bjoern O Bachmann
- Department of Ophthalmology, University of Cologne, Cologne, Germany
| | - Claus Cursiefen
- Department of Ophthalmology, University of Cologne, Cologne, Germany; Center for Molecular Medicine Cologne (CMMC), University of Cologne, Cologne, Germany.
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Hori J, Yamaguchi T, Keino H, Hamrah P, Maruyama K. Immune privilege in corneal transplantation. Prog Retin Eye Res 2019; 72:100758. [PMID: 31014973 DOI: 10.1016/j.preteyeres.2019.04.002] [Citation(s) in RCA: 92] [Impact Index Per Article: 18.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2019] [Revised: 04/14/2019] [Accepted: 04/16/2019] [Indexed: 12/13/2022]
Abstract
Corneal transplantation is the most successful solid organ transplantation performed in humans. The extraordinary success of orthotopic corneal allografts, in both humans and experimental animals, is related to the phenomenon of "immune privilege". Inflammation is self-regulated to preserve ocular functions because the eye has immune privilege. At present, three major mechanisms are considered to provide immune privilege in corneal transplantation: 1) anatomical, cellular, and molecular barriers in the cornea; 2) tolerance related to anterior chamber-associated immune deviation and regulatory T cells; and 3) an immunosuppressive intraocular microenvironment. This review describes the mechanisms of immune privilege that have been elucidated from animal models of ocular inflammation, especially those involving corneal transplantation, and its relevance for the clinic. An update on molecular, cellular, and neural interactions in local and systemic immune regulation is provided. Therapeutic strategies for restoring immune privilege are also discussed.
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Affiliation(s)
- Junko Hori
- Department of Ophthalmology, Nippon Medical School, 1-1-5 Sendagi, Bunkyo-ku, Tokyo, 113-8603, Japan; Department of Ophthalmology, Nippon Medical School, Tama-Nagayama Hospital, 1-7-1 Nagayama, Tama, Tokyo, 206-8512, Japan.
| | - Takefumi Yamaguchi
- Department of Ophthalmology, Tokyo Dental College Ichikawa General Hospital, 5-11-13 Sugano, Ichikawa-shi, Chiba, 272-8513, Japan; Department of Ophthalmology, Keio University School of Medicine, 35 Shinanomachi, Shinjuku-ku, Tokyo, 160-8582, Japan
| | - Hiroshi Keino
- Department of Ophthalmology, Kyorin University School of Medicine, 6-20-2 Shinkawa, Mitaka-shi, Tokyo, 181-8611, Japan
| | - Pedram Hamrah
- Center for Translational Ocular Immunology, Tufts Medical Center, Tufts University School of Medicine, Tufts University, 800 Washington St, Boston, MA, 02111, USA; Department of Ophthalmology, Tufts Medical Center, Tufts University School of Medicine, Tufts University, 800 Washington St, Boston, MA, 02111, USA
| | - Kazuichi Maruyama
- Department of Innovative Visual Science, Graduate School of Medicine, Osaka University, 2-2 Yamadaoka, Suita, Osaka 565-0871, Japan
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Neelam S, Mellon J, Wilkerson A, Niederkorn JY. Induction of Contrasuppressor Cells and Loss of Immune Privilege Produced by Corneal Nerve Ablation. Invest Ophthalmol Vis Sci 2019; 59:4738-4747. [PMID: 30267096 PMCID: PMC6161365 DOI: 10.1167/iovs.18-24894] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
Purpose Severing of corneal nerves in preparation of corneal transplantation abolishes immune privilege of subsequent corneal transplants placed into either eye: a phenomenon termed sympathetic loss of immune privilege (SLIP). SLIP is due to the disabling of T regulatory cells (Tregs) by CD11c+ contrasuppressor (CS) cells. This study characterized the induction, function, and manipulation of CS cell activity and the effect of these cells on Tregs induced by anterior chamber-associated immune deviation (ACAID). Methods CS cells were induced using a 2.0-mm trephine to score the corneal epithelium. CD11c+ CS cells were evaluated by adoptive transfer and by their capacity to disable CD8+ ACAID Tregs in local adoptive transfer (LAT) of suppression assays. CD11c+ cells were deleted from the ocular surface by subconjunctival injection of clodronate-containing liposomes. Results CD11c+ CS cell were radiosenstive and long lived. As few as 1000 CS cells blocked the suppressive activity of previously generated CD8+ ACAID Tregs, indicating that CS cells act at the efferent arm of the immune response. Depletion of resident CD11c+ cells at the ocular surface prevented the generation of CS cells. Conclusions Corneal nerve injury that occurs during keratoplasty converts ocular surface CD11c+ cells into CS cells that block CD8+ Tregs, which are induced by introducing antigens into the anterior chamber (i.e., ACAID Tregs). Depletion of CD11c+ cells at the ocular surface prevents the generation of CS cells and may be a useful strategy for preventing SLIP and enhancing the survival of second corneal transplants.
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Affiliation(s)
- Sudha Neelam
- Department of Ophthalmology, University of Texas Southwestern Medical Center, Dallas, Texas, United States
| | - Jessamee Mellon
- Department of Ophthalmology, University of Texas Southwestern Medical Center, Dallas, Texas, United States
| | - Amber Wilkerson
- Department of Ophthalmology, University of Texas Southwestern Medical Center, Dallas, Texas, United States
| | - Jerry Y Niederkorn
- Department of Ophthalmology, University of Texas Southwestern Medical Center, Dallas, Texas, United States
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Lee HK, Kim KW, Ryu JS, Jeong HJ, Lee SM, Kim MK. Bilateral Effect of the Unilateral Corneal Nerve Cut on Both Ocular Surface and Lacrimal Gland. ACTA ACUST UNITED AC 2019; 60:430-441. [DOI: 10.1167/iovs.18-26051] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Affiliation(s)
- Hyo Kyung Lee
- Department of Ophthalmology, Seoul National University College of Medicine, Seoul, Korea
- Laboratory of Ocular Regenerative Medicine and Immunology, Seoul Artificial Eye Center, Seoul National University Hospital Clinical Research Institute, Seoul, Korea
| | - Kyoung Woo Kim
- Department of Ophthalmology, Seoul National University College of Medicine, Seoul, Korea
- Laboratory of Ocular Regenerative Medicine and Immunology, Seoul Artificial Eye Center, Seoul National University Hospital Clinical Research Institute, Seoul, Korea
| | - Jin Suk Ryu
- Laboratory of Ocular Regenerative Medicine and Immunology, Seoul Artificial Eye Center, Seoul National University Hospital Clinical Research Institute, Seoul, Korea
| | - Hyun Jeong Jeong
- Laboratory of Ocular Regenerative Medicine and Immunology, Seoul Artificial Eye Center, Seoul National University Hospital Clinical Research Institute, Seoul, Korea
| | - Sang-Mok Lee
- HanGil Eye Hospital, Catholic Kwandong University College of Medicine, Incheon, South Korea
| | - Mee Kum Kim
- Department of Ophthalmology, Seoul National University College of Medicine, Seoul, Korea
- Laboratory of Ocular Regenerative Medicine and Immunology, Seoul Artificial Eye Center, Seoul National University Hospital Clinical Research Institute, Seoul, Korea
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Guzmán M, Miglio MS, Zgajnar NR, Colado A, Almejún MB, Keitelman IA, Sabbione F, Fuentes F, Trevani AS, Giordano MN, Galletti JG. The mucosal surfaces of both eyes are immunologically linked by a neurogenic inflammatory reflex involving TRPV1 and substance P. Mucosal Immunol 2018; 11:1441-1453. [PMID: 29867077 DOI: 10.1038/s41385-018-0040-5] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2018] [Revised: 04/08/2018] [Accepted: 04/15/2018] [Indexed: 02/04/2023]
Abstract
Immunological interdependence between the two eyes has been reported for the cornea and the retina but not for the ocular mucosal surface. Intriguingly, patients frequently report ocular surface-related symptoms in the other eye after unilateral ocular surgery. Here we show how unilateral eye injuries in mice affect the mucosal immune response of the opposite ocular surface. We report that, despite the lack of lymphatic cross-drainage, a neurogenic inflammatory reflex in the contralateral conjunctiva is sufficient to increase, first, epithelial nuclear factor kappa B signaling, then, dendritic cell maturation, and finally, expansion of effector, instead of regulatory, T cells in the draining lymph node, leading to disrupted ocular mucosal tolerance. We also show that damage to ocular surface nerves is required. Using pharmacological inhibitors and agonists, we identified transient receptor potential vanilloid 1 (TRPV1) channel as the receptor sensing tissue damage in the injured eye and substance P released in the opposite ocular surface as the effector of the sympathetic response. Finally, blocking either step prevented subsequent ocular allergic reactions in the opposite eye in a unilateral corneal alkali burn model. This study demonstrates that both ocular surfaces are immunologically linked and suggests potential therapeutic targets for intervention.
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Affiliation(s)
- Mauricio Guzmán
- Immunology Laboratory, Institute of Experimental Medicine (IMEX), National Academy of Medicine/CONICET, Buenos Aires, Argentina
| | - Maximiliano S Miglio
- Immunology Laboratory, Institute of Experimental Medicine (IMEX), National Academy of Medicine/CONICET, Buenos Aires, Argentina
| | - Nadia R Zgajnar
- Nuclear Receptors Laboratory, Institute of Experimental Biology & Medicine (IBYME)-CONICET, Buenos Aires, Argentina
| | - Ana Colado
- Immunology Laboratory, Institute of Experimental Medicine (IMEX), National Academy of Medicine/CONICET, Buenos Aires, Argentina
| | - María B Almejún
- Immunology Laboratory, Institute of Experimental Medicine (IMEX), National Academy of Medicine/CONICET, Buenos Aires, Argentina
| | - Irene A Keitelman
- Immunology Laboratory, Institute of Experimental Medicine (IMEX), National Academy of Medicine/CONICET, Buenos Aires, Argentina
| | - Florencia Sabbione
- Immunology Laboratory, Institute of Experimental Medicine (IMEX), National Academy of Medicine/CONICET, Buenos Aires, Argentina
| | - Federico Fuentes
- Immunology Laboratory, Institute of Experimental Medicine (IMEX), National Academy of Medicine/CONICET, Buenos Aires, Argentina
| | - Analía S Trevani
- Immunology Laboratory, Institute of Experimental Medicine (IMEX), National Academy of Medicine/CONICET, Buenos Aires, Argentina.,Microbiology, Parasitology & Immunology Department, School of Medicine, University of Buenos Aires, Buenos Aires, Argentina
| | - Mirta N Giordano
- Immunology Laboratory, Institute of Experimental Medicine (IMEX), National Academy of Medicine/CONICET, Buenos Aires, Argentina.,Microbiology, Parasitology & Immunology Department, School of Medicine, University of Buenos Aires, Buenos Aires, Argentina
| | - Jeremías G Galletti
- Immunology Laboratory, Institute of Experimental Medicine (IMEX), National Academy of Medicine/CONICET, Buenos Aires, Argentina.
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Foulsham W, Coco G, Amouzegar A, Chauhan SK, Dana R. When Clarity Is Crucial: Regulating Ocular Surface Immunity. Trends Immunol 2018; 39:288-301. [PMID: 29248310 PMCID: PMC5880704 DOI: 10.1016/j.it.2017.11.007] [Citation(s) in RCA: 54] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2017] [Revised: 11/28/2017] [Accepted: 11/29/2017] [Indexed: 12/23/2022]
Abstract
The ocular surface is a unique mucosal immune compartment in which anatomical, physiological, and immunological features act in concert to foster a particularly tolerant microenvironment. These mechanisms are vital to the functional competence of the eye, a fact underscored by the devastating toll of excessive inflammation at the cornea - blindness. Recent data have elucidated the contributions of specific anatomical components, immune cells, and soluble immunoregulatory factors in promoting homeostasis at the ocular surface. We highlight research trends at this distinctive mucosal barrier and identify crucial gaps in our current knowledge.
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Affiliation(s)
- William Foulsham
- Schepens Eye Research Institute, Massachusetts Eye and Ear Infirmary, Department of Ophthalmology, Harvard Medical School, Boston, MA, USA; University College London (UCL) Institute of Ophthalmology, University College London, London, UK
| | - Giulia Coco
- Schepens Eye Research Institute, Massachusetts Eye and Ear Infirmary, Department of Ophthalmology, Harvard Medical School, Boston, MA, USA
| | - Afsaneh Amouzegar
- Schepens Eye Research Institute, Massachusetts Eye and Ear Infirmary, Department of Ophthalmology, Harvard Medical School, Boston, MA, USA
| | - Sunil K Chauhan
- Schepens Eye Research Institute, Massachusetts Eye and Ear Infirmary, Department of Ophthalmology, Harvard Medical School, Boston, MA, USA.
| | - Reza Dana
- Schepens Eye Research Institute, Massachusetts Eye and Ear Infirmary, Department of Ophthalmology, Harvard Medical School, Boston, MA, USA.
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Zhong W, Montana M, Santosa SM, Isjwara ID, Huang YH, Han KY, O'Neil C, Wang A, Cortina MS, de la Cruz J, Zhou Q, Rosenblatt MI, Chang JH, Azar DT. Angiogenesis and lymphangiogenesis in corneal transplantation-A review. Surv Ophthalmol 2017; 63:453-479. [PMID: 29287709 DOI: 10.1016/j.survophthal.2017.12.008] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2017] [Revised: 12/12/2017] [Accepted: 12/18/2017] [Indexed: 12/13/2022]
Abstract
Corneal transplantation has been proven effective for returning the gift of sight to those affected by corneal disorders such as opacity, injury, and infections that are a leading cause of blindness. Immune privilege plays an important role in the success of corneal transplantation procedures; however, immune rejection reactions do occur, and they, in conjunction with a shortage of corneal donor tissue, continue to pose major challenges. Corneal immune privilege is important to the success of corneal transplantation and closely related to the avascular nature of the cornea. Corneal avascularity may be disrupted by the processes of angiogenesis and lymphangiogenesis, and for this reason, these phenomena have been a focus of research in recent years. Through this research, therapies addressing certain rejection reactions related to angiogenesis have been developed and implemented. Corneal donor tissue shortages also have been addressed by the development of new materials to replace the human donor cornea. These advancements, along with other improvements in the corneal transplantation procedure, have contributed to an improved success rate for corneal transplantation. We summarize recent developments and improvements in corneal transplantation, including the current understanding of angiogenesis mechanisms, the anti-angiogenic and anti-lymphangiogenic factors identified to date, and the new materials being used. Additionally, we discuss future directions for research in corneal transplantation.
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Affiliation(s)
- Wei Zhong
- Department of Ophthalmology, China-Japan Union Hospital of Jilin University, Changchun, Jilin, P.R. China; Department of Ophthalmology and Visual Sciences, Illinois Eye and Ear Infirmary, College of Medicine, University of Illinois at Chicago, Chicago, Illinois, USA
| | - Mario Montana
- Department of Ophthalmology and Visual Sciences, Illinois Eye and Ear Infirmary, College of Medicine, University of Illinois at Chicago, Chicago, Illinois, USA
| | - Samuel M Santosa
- Department of Ophthalmology and Visual Sciences, Illinois Eye and Ear Infirmary, College of Medicine, University of Illinois at Chicago, Chicago, Illinois, USA
| | - Irene D Isjwara
- Department of Ophthalmology and Visual Sciences, Illinois Eye and Ear Infirmary, College of Medicine, University of Illinois at Chicago, Chicago, Illinois, USA
| | - Yu-Hui Huang
- Department of Ophthalmology and Visual Sciences, Illinois Eye and Ear Infirmary, College of Medicine, University of Illinois at Chicago, Chicago, Illinois, USA
| | - Kyu-Yeon Han
- Department of Ophthalmology and Visual Sciences, Illinois Eye and Ear Infirmary, College of Medicine, University of Illinois at Chicago, Chicago, Illinois, USA
| | - Christopher O'Neil
- Department of Ophthalmology and Visual Sciences, Illinois Eye and Ear Infirmary, College of Medicine, University of Illinois at Chicago, Chicago, Illinois, USA
| | - Ashley Wang
- Department of Ophthalmology and Visual Sciences, Illinois Eye and Ear Infirmary, College of Medicine, University of Illinois at Chicago, Chicago, Illinois, USA
| | - Maria Soledad Cortina
- Department of Ophthalmology and Visual Sciences, Illinois Eye and Ear Infirmary, College of Medicine, University of Illinois at Chicago, Chicago, Illinois, USA
| | - Jose de la Cruz
- Department of Ophthalmology and Visual Sciences, Illinois Eye and Ear Infirmary, College of Medicine, University of Illinois at Chicago, Chicago, Illinois, USA
| | - Qiang Zhou
- Department of Ophthalmology and Visual Sciences, Illinois Eye and Ear Infirmary, College of Medicine, University of Illinois at Chicago, Chicago, Illinois, USA
| | - Mark I Rosenblatt
- Department of Ophthalmology and Visual Sciences, Illinois Eye and Ear Infirmary, College of Medicine, University of Illinois at Chicago, Chicago, Illinois, USA
| | - Jin-Hong Chang
- Department of Ophthalmology and Visual Sciences, Illinois Eye and Ear Infirmary, College of Medicine, University of Illinois at Chicago, Chicago, Illinois, USA.
| | - Dimitri T Azar
- Department of Ophthalmology and Visual Sciences, Illinois Eye and Ear Infirmary, College of Medicine, University of Illinois at Chicago, Chicago, Illinois, USA.
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Suvas S. Role of Substance P Neuropeptide in Inflammation, Wound Healing, and Tissue Homeostasis. THE JOURNAL OF IMMUNOLOGY 2017; 199:1543-1552. [PMID: 28827386 DOI: 10.4049/jimmunol.1601751] [Citation(s) in RCA: 206] [Impact Index Per Article: 29.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/12/2016] [Accepted: 06/13/2017] [Indexed: 11/19/2022]
Abstract
Substance P (SP) is an undecapeptide present in the CNS and the peripheral nervous system. SP released from the peripheral nerves exerts its biological and immunological activity via high-affinity neurokinin 1 receptor (NK1R). SP is also produced by immune cells and acts as an autocrine or paracrine fashion to regulate the function of immune cells. In addition to its proinflammatory role, SP and its metabolites in combination with insulin-like growth factor-1 are shown to promote the corneal epithelial wound healing. Recently, we showed an altered ocular surface homeostasis in unmanipulated NK1R-/- mice, suggesting the role of SP-NK1R signaling in ocular surface homeostasis under steady-state. This review summarizes the immunobiology of SP and its effect on immune cells and immunity to microbial infection. In addition, the effect of SP in inflammation, wound healing, and corneal epithelial homeostasis in the eye is discussed.
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Affiliation(s)
- Susmit Suvas
- Department of Ophthalmology/Kresge Eye Institute, Wayne State University School of Medicine, Detroit, MI 48201; .,Department of Anatomy and Cell Biology, Wayne State University School of Medicine, Detroit, MI 48201; and .,Department of Immunology and Microbiology, Wayne State University School of Medicine, Detroit, MI 48201
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Abstract
Pain associated with mechanical, chemical, and thermal heat stimulation of the ocular surface is mediated by trigeminal ganglion neurons, while cold thermoreceptors detect wetness and reflexly maintain basal tear production and blinking rate. These neurons project into two regions of the trigeminal brain stem nuclear complex: ViVc, activated by changes in the moisture of the ocular surface and VcC1, mediating sensory-discriminative aspects of ocular pain and reflex blinking. ViVc ocular neurons project to brain regions that control lacrimation and spontaneous blinking and to the sensory thalamus. Secretion of the main lacrimal gland is regulated dominantly by autonomic parasympathetic nerves, reflexly activated by eye surface sensory nerves. These also evoke goblet cell secretion through unidentified efferent fibers. Neural pathways involved in the regulation of meibomian gland secretion or mucin release have not been identified. In dry eye disease, reduced tear secretion leads to inflammation and peripheral nerve damage. Inflammation causes sensitization of polymodal and mechano-nociceptor nerve endings and an abnormal increase in cold thermoreceptor activity, altogether evoking dryness sensations and pain. Long-term inflammation and nerve injury alter gene expression of ion channels and receptors at terminals and cell bodies of trigeminal ganglion and brainstem neurons, changing their excitability, connectivity and impulse firing. Perpetuation of molecular, structural and functional disturbances in ocular sensory pathways ultimately leads to dysestesias and neuropathic pain referred to the eye surface. Pain can be assessed with a variety of questionaires while the status of corneal nerves is evaluated with esthesiometry and with in vivo confocal microscopy.
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Affiliation(s)
- Mehran Zarei-Ghanavati
- Eye Research Center, Farabi Eye Hospital, Tehran University of Medical Sciences, Tehran, Iran
- Sussex Eye Hospital, Brighton, Eastern Road, England BN2 5BF
| | - Christopher Liu
- Sussex Eye Hospital, Brighton, Eastern Road, England BN2 5BF
- Brighton and Sussex Medical School, Brighton, England
- Tongdean Eye Clinic, Hove, England
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49
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Mo J, Neelam S, Mellon J, Brown JR, Niederkorn JY. Effect of Corneal Nerve Ablation on Immune Tolerance Induced by Corneal Allografts, Oral Immunization, or Anterior Chamber Injection of Antigens. Invest Ophthalmol Vis Sci 2017; 58:137-148. [PMID: 28114571 PMCID: PMC5231905 DOI: 10.1167/iovs.16-20601] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
Purpose Severing corneal nerves during corneal transplantation does not affect first corneal transplants, but abolishes immune privilege of subsequent corneal allografts. This abrogation of immune privilege is attributable to the disabling of T regulatory cells (T regs) induced by corneal transplantation. The goal of this study was to determine if severing corneal nerves induces the development of contrasuppressor (CS) cells, which disable T regs that impair other forms of immune tolerance. Methods Effect of corneal nerve ablation on immune tolerance was assessed in four forms of immune tolerance: anterior chamber-associated immune deviation (ACAID); oral tolerance; corneal transplantation, and intravenously (IV) induced immune tolerance. T regulatory cell activity was assessed by adoptive transfer and by local adoptive transfer (LAT) of suppression assays. Results Corneal nerve ablation prevented ACAID and oral tolerance, but did not affect IV-induced immune tolerance. Contrasuppressor cells blocked the action of T regs that were generated by anterior chamber injection, oral tolerance, or orthotopic corneal transplantation. The neuropeptide substance P (SP) was crucial for contrasuppressor activity as CS cells could not be induced in SP-/- mice and the SP receptor inhibitor, Spantide II, prevented the expression of CS cell activity in vivo. Contrasuppressor cells expressed CD11c surface marker that identifies dendritic cells (DC). Conclusions The loss of immune privilege produced by corneal nerve ablation following corneal transplantation extends beyond the eye and also affects immune tolerance induced through mucosal surfaces and appears to be mediated by a novel cell population of CD11c+ CS cells that disables T regs.
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Affiliation(s)
- Juan Mo
- Department of Ophthalmology, University of Texas Southwestern Medical Center, Dallas, Texas, United States
| | - Sudha Neelam
- Department of Ophthalmology, University of Texas Southwestern Medical Center, Dallas, Texas, United States
| | - Jessamee Mellon
- Department of Ophthalmology, University of Texas Southwestern Medical Center, Dallas, Texas, United States
| | - Joseph R Brown
- Department of Ophthalmology, University of Texas Southwestern Medical Center, Dallas, Texas, United States
| | - Jerry Y Niederkorn
- Department of Ophthalmology, University of Texas Southwestern Medical Center, Dallas, Texas, United States
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50
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Bilateral Alterations in Corneal Nerves, Dendritic Cells, and Tear Cytokine Levels in Ocular Surface Disease. Cornea 2017; 35 Suppl 1:S65-S70. [PMID: 27617877 DOI: 10.1097/ico.0000000000000989] [Citation(s) in RCA: 42] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
This review summarizes the recent literature regarding corneal imaging in human subjects using in vivo confocal microscopy. It also covers the recent literature on corneal immune cells, nerves, and tear cytokine levels in ocular surface diseases as well as corneal immune privilege. The significance of interactions between corneal immune cells and nerves in health, neurotrophic keratopathy, and infectious keratitis is discussed. Furthermore, bilateral alterations of immune cells and nerves in clinically unilateral corneal diseases and the link to changes of tear cytokines or neuropeptide levels in contralateral eyes are described. Recent studies reported increased density and morphologic changes of corneal dendritic cells in ocular surface disease that correlated with a decrease in subbasal nerve and corneal nerve density, suggesting potential interactions between the immune and nervous systems in the cornea. Although the relevance of tear cytokines is poorly understood, tear cytokines might have an important role in the pathogenesis of ocular surface diseases. In humans and experimental animal models, alterations in immune cells, cytokines, and immunomodulatory neuropeptide levels in contralateral eyes might mediate the incidence of bilateral infectious keratitis and loss of immune privilege of the cornea in bilateral corneal transplantation or neurotrophic keratopathy cases. The discovery of bilateral alterations of immune cells and nerves in ocular surface diseases is considered the missing link between the immune and nervous systems in the cornea, and demonstrates how studies of animal models and humans aid our understanding of human corneal disease phenomena.
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