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Rolando M, Barabino S. Are there Clinical Ways to Assess Inflammation in Dry Eye Disease? Ocul Immunol Inflamm 2021; 29:1183-1189. [PMID: 34227903 DOI: 10.1080/09273948.2021.1916540] [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] [Indexed: 10/20/2022]
Abstract
In the diagnostic process of dry eye disease, the detection of inflammatory activity is critical in order to evaluate the risk of progression and immunologic shift of the disease, to predict patient response to treatment, and to design an efficient therapeutic strategy, including artificial tear replacement, punctal occlusion or anti-inflammatory therapy.Even if it is difficult to quantify, some indicators of the presence of inflammation are collectible during the examination of the ocular surface in a first-line clinical setting. This review presents and critically discusses the assessment of inflammation in dry eye disease in clinical practice.
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Affiliation(s)
- Maurizio Rolando
- Ocular Surface and Dry Eye Clinic, ISPRE Ophthalmica, Genoa, Italy
| | - Stefano Barabino
- Ocular Surface and Dry Eye Center, ASST Fatebenefratelli-Sacco, Sacco Hospital-University of Milan, Milan, Italy
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2
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Affiliation(s)
- Timothy R. Golding
- Corneal Biophysics Laboratory, Department of Optometry, University of Melbourne
| | - Noel A. Brennan
- Corneal Biophysics Laboratory, Department of Optometry, University of Melbourne
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Brockhausen I, Elimova E, Woodward AM, Argüeso P. Glycosylation pathways of human corneal and conjunctival epithelial cell mucins. Carbohydr Res 2018; 470:50-56. [PMID: 30392563 DOI: 10.1016/j.carres.2018.10.004] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2018] [Revised: 10/15/2018] [Accepted: 10/18/2018] [Indexed: 12/20/2022]
Abstract
Mucin glycoproteins on the ocular surface are rich in O-glycans and have important roles in the protection from physical, chemical and microbial impact. In this work, we have cultured human corneal and conjunctival epithelial cells to examine the glycosyltransferase activities that synthesize the O-glycans of mucins. The results indicate that ocular surface epithelial cells have active enzymes that synthesize O-glycans with sialylated core 1, Galβ1-3GalNAcα, and core 2, GlcNAcβ1-6(Galβ1-3)GalNAcα structures which corresponds to previous structural studies. Eye cells also have enzymes that synthesize complex N-glycans that are found on mucins. Results from treatment of eye cells with TNFα suggest that epithelial O-glycosylation changes in a dynamic fashion during inflammatory stimuli of the eye surface.
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Affiliation(s)
- Inka Brockhausen
- Department of Biomedical and Molecular Sciences, Queen's University, Kingston, Ontario, Canada.
| | - Elena Elimova
- Department of Biomedical and Molecular Sciences, Queen's University, Kingston, Ontario, Canada
| | - Ashley M Woodward
- Schepens Eye Research Institute of Massachusetts Eye and Ear, Department of Ophthalmology, Harvard Medical School, Boston, MA, United States
| | - Pablo Argüeso
- Schepens Eye Research Institute of Massachusetts Eye and Ear, Department of Ophthalmology, Harvard Medical School, Boston, MA, United States
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Bron AJ, de Paiva CS, Chauhan SK, Bonini S, Gabison EE, Jain S, Knop E, Markoulli M, Ogawa Y, Perez V, Uchino Y, Yokoi N, Zoukhri D, Sullivan DA. TFOS DEWS II pathophysiology report. Ocul Surf 2017; 15:438-510. [PMID: 28736340 DOI: 10.1016/j.jtos.2017.05.011] [Citation(s) in RCA: 949] [Impact Index Per Article: 135.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2017] [Accepted: 05/26/2017] [Indexed: 12/18/2022]
Abstract
The TFOS DEWS II Pathophysiology Subcommittee reviewed the mechanisms involved in the initiation and perpetuation of dry eye disease. Its central mechanism is evaporative water loss leading to hyperosmolar tissue damage. Research in human disease and in animal models has shown that this, either directly or by inducing inflammation, causes a loss of both epithelial and goblet cells. The consequent decrease in surface wettability leads to early tear film breakup and amplifies hyperosmolarity via a Vicious Circle. Pain in dry eye is caused by tear hyperosmolarity, loss of lubrication, inflammatory mediators and neurosensory factors, while visual symptoms arise from tear and ocular surface irregularity. Increased friction targets damage to the lids and ocular surface, resulting in characteristic punctate epithelial keratitis, superior limbic keratoconjunctivitis, filamentary keratitis, lid parallel conjunctival folds, and lid wiper epitheliopathy. Hybrid dry eye disease, with features of both aqueous deficiency and increased evaporation, is common and efforts should be made to determine the relative contribution of each form to the total picture. To this end, practical methods are needed to measure tear evaporation in the clinic, and similarly, methods are needed to measure osmolarity at the tissue level across the ocular surface, to better determine the severity of dry eye. Areas for future research include the role of genetic mechanisms in non-Sjögren syndrome dry eye, the targeting of the terminal duct in meibomian gland disease and the influence of gaze dynamics and the closed eye state on tear stability and ocular surface inflammation.
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Affiliation(s)
- Anthony J Bron
- Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford, UK; Vision and Eye Research Unit, Anglia Ruskin University, Cambridge, UK.
| | - Cintia S de Paiva
- Department of Ophthalmology, Baylor College of Medicine, Houston, TX, USA
| | - Sunil K Chauhan
- Schepens Eye Research Institute & Massachusetts Eye and Ear, Harvard Medical School, Boston, MA, USA
| | - Stefano Bonini
- Department of Ophthalmology, University Campus Biomedico, Rome, Italy
| | - Eric E Gabison
- Department of Ophthalmology, Fondation Ophtalmologique Rothschild & Hôpital Bichat Claude Bernard, Paris, France
| | - Sandeep Jain
- Department of Ophthalmology and Visual Sciences, University of Illinois at Chicago, Chicago, IL, USA
| | - Erich Knop
- Departments of Cell and Neurobiology and Ocular Surface Center Berlin, Charité - Universitätsmedizin Berlin, Berlin, Germany
| | - Maria Markoulli
- School of Optometry and Vision Science, University of New South Wales, Sydney, Australia
| | - Yoko Ogawa
- Department of Ophthalmology, Keio University School of Medicine, Tokyo, Japan
| | - Victor Perez
- Department of Ophthalmology, Bascom Palmer Eye Institute, University of Miami, Miami, FL, USA
| | - Yuichi Uchino
- Department of Ophthalmology, Keio University School of Medicine, Tokyo, Japan
| | - Norihiko Yokoi
- Department of Ophthalmology, Kyoto Prefectural University of Medicine, Kyoto, Japan
| | - Driss Zoukhri
- Tufts University School of Dental Medicine, Boston, MA, USA
| | - David A Sullivan
- Schepens Eye Research Institute & Massachusetts Eye and Ear, Harvard Medical School, Boston, MA, USA
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Effect of diquafosol tetrasodium eye drop for persistent dry eye after laser in situ keratomileusis. Cornea 2015; 33:659-62. [PMID: 24858017 DOI: 10.1097/ico.0000000000000136] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
PURPOSE To evaluate the effect of diquafosol tetrasodium (DQS) for the treatment of persistent dry eye after laser in situ keratomileusis (LASIK). SETTING Miyata Eye Hospital, Miyazaki, Japan. DESIGN Noncomparative case series. METHODS This prospective study included 30 eyes of 15 patients in whom dry eye had persisted for over 12 months after LASIK, and the symptoms had not improved with artificial tears and sodium hyaluronate treatment. In addition, treatment with DQS 3% eye drops, 6 times a day, was performed for 12 weeks. Best-corrected visual acuity, tear secretion with the Schirmer test, tear break-up time, and fluorescein and lissamine green staining scores on the cornea and conjunctiva were examined before and at 1, 4, and 12 weeks after the addition. A subjective questionnaire of 14 symptoms was also assessed before and 12 weeks after treatment. RESULTS The fluorescein and lissamine green staining scores significantly improved over 12 weeks; however, the best-corrected visual acuity and tear secretion did not change. The symptoms of fatigue, dryness, grittiness, discomfort, difficulty in reading, and discomfort within the area of dryness improved after the additional DQS treatment. CONCLUSIONS The DQS treatment improved the subjective and objective symptoms of persistent dry eye after LASIK. Increased mucin production because of the addition of DQS probably improved the tear film stability and reduced the symptoms of dry eye in patients who had persistent dry eye after LASIK.
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Abstract
PURPOSE The aim of this study was to investigate the effect of lubricant eyedrops containing propylene glycol 400 (PEG) and polyethylene glycol (PG) with hydroxypropyl guar (HP-guar) as a gelling agent on the precorneal mucous layer in vivo. METHODS Sixteen New Zealand white rabbits were randomly assigned to 1 of 4 groups. All rabbits received PEG/PG/HP-guar tear products in the right eye. PEG/PG/HP-guar with Polyquad, 0.1% hyaluronate sodium, 0.5% carboxymethylcellulose, or phosphate-buffered saline was placed in the left eyes of animals in each group. All eyedrops were used 4 times a day for 7 days. An additional 8 rabbits were randomly assigned to 1 of 2 groups. One group received PEG/PG/HP-guar products 4 times a day for 7 days (long-term exposure group), and the other group received PEG/PG/HP-guar products 3 times at 5-minute intervals (short-term exposure group). Fifteen minutes after the last drop was administered, each cornea was immediately excised and mucous layer thickness measured by transmission electron microscopy. RESULTS Mucous layer thickness was significantly greater in eyes treated with PEG/PG/HP-guar products compared with those treated with 0.1% hyaluronate sodium, 0.5% carboxymethylcellulose, or phosphate-buffered saline (all P values < 0.001). There were no significant differences in mucous layer thickness between PEG/PG/HP-guar products and PEG/PG/HP-guar with Polyquad or in the long- and short-term exposure animals. CONCLUSIONS This study demonstrates that even a short exposure to PEG/PG/HP-guar tear product increased precorneal mucous layer thickness.
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Chen YT, Nikulina K, Lazarev S, Bahrami AF, Noble LB, Gallup M, McNamara NA. Interleukin-1 as a phenotypic immunomodulator in keratinizing squamous metaplasia of the ocular surface in Sjögren's syndrome. THE AMERICAN JOURNAL OF PATHOLOGY 2010; 177:1333-43. [PMID: 20696775 DOI: 10.2353/ajpath.2010.100227] [Citation(s) in RCA: 63] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Chronic inflammation of the ocular surface in Sjögren's syndrome (SS) is associated with a vision-threatening, phenotypic change of the ocular surface, which converts from a nonkeratinized, stratified squamous epithelium to a nonsecretory, keratinized epithelium. This pathological process is known as squamous metaplasia. Based on a significant correlation between ocular surface interleukin (IL)-1beta expression and squamous metaplasia in patients with SS, we investigated the role of IL-1 in the pathogenesis of squamous metaplasia in an animal model that mimics the clinical characteristics of SS. Using autoimmune-regulator (aire)-deficient mice, we assessed lacrimal gland and ocular surface immunopathology by quantifying the infiltration of major histocompatibility complex class II(+) (I-A(d+)) dendritic cells and CD4(+) T cells. We examined squamous metaplasia using a biomarker of keratinization, small proline-rich protein 1B. We used lissamine green staining as a readout for ocular surface epitheliopathy and Alcian blue/periodic acid-Schiff histochemical analysis to characterize goblet cell muco-glycoconjugates. Within 8 weeks, the eyes of aire-deficient mice were pathologically keratinized with significant epithelial damage and altered mucin glycosylation. Although knockdown of IL-1 receptor 1 did not attenuate lymphocytic infiltration of the lacrimal gland or eye, it significantly reduced ocular surface keratinization, epitheliopathy, and muco-glycoconjugate acidification. These data demonstrate a phenotypic modulation role for IL-1 in the pathogenesis of squamous metaplasia and suggest that IL-1 receptor 1-targeted therapies may be beneficial for treating ocular surface disease associated with SS.
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Affiliation(s)
- Ying-Ting Chen
- University of California, San Francisco, Francis I. Proctor Foundation, San Francisco, CA 94143, USA
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Guzman-Aranguez A, Argüeso P. Structure and Biological Roles of Mucin-type O-glycans at the Ocular Surface. Ocul Surf 2010; 8:8-17. [DOI: 10.1016/s1542-0124(12)70213-6] [Citation(s) in RCA: 81] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
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Guzman-Aranguez A, Mantelli F, Argüeso P. Mucin-type O-glycans in tears of normal subjects and patients with non-Sjögren's dry eye. Invest Ophthalmol Vis Sci 2009; 50:4581-7. [PMID: 19407012 PMCID: PMC2751810 DOI: 10.1167/iovs.09-3563] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
PURPOSE O-linked carbohydrates (O-glycans) contribute to the hydrophilic character of mucins in mucosal tissues. This study was conducted to identify the repertoire of O-glycans in the tear film and the glycosyltransferases associated with their biosynthesis, in normal subjects and patients with non-Sjögren's dry eye. METHODS Human tear fluid was collected from the inferior conjunctival fornix. O-glycans were released by hydrazinolysis, labeled with 2-aminobenzamide, and analyzed by fluorometric, high-performance liquid chromatography (HPLC) coupled with exoglycosidase digestions. O-glycan structures identified in tears were related to potential biosynthetic pathways in human conjunctival epithelium by using a glycogene microarray database. Lectin-binding analyses were performed with agglutinins from Arachis hypogaea, Maackia amurensis, and Sambucus nigra. RESULTS The O-glycan profile of human tears consisted primarily of core 1 (Gal beta 1-3GalNAc alpha 1-Ser/Thr)-based structures. Mono-sialyl O-glycans represented approximately 66% of the glycan pool, with alpha2-6-sialyl core 1 being the predominant O-glycan structure in human tears (48%). Four families of glycosyltransferases potentially related to the biosynthesis of these structures were identified in human conjunctiva. These included 13 polypeptide-GalNAc-transferases (GALNT), the core 1 beta-3-galactosyltransferase (T-synthase), three alpha2-6-sialyltransferases (ST6GalNAc), and two alpha2-3-sialyltransferases (ST3Gal). No significant differences in total amount of O-glycans were detected between tears of normal subjects and patients with dry eye, by HPLC and lectin blot. Likewise, no differences in glycosyltransferase expression were found by glycogene microarray. CONCLUSIONS This study identified the most common mucin-type O-glycans in human tears and their expected biosynthetic pathways in ocular surface epithelia. Patients with non-Sjögren's dry eye showed no alterations in composition and amount of O-glycans in the tear fluid.
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Affiliation(s)
- Ana Guzman-Aranguez
- Schepens Eye Research Institute and Department of Ophthalmology, Harvard Medical School, Boston, Massachusetts 02114, USA
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Abstract
PURPOSE OF REVIEW The purpose of the present review is to describe new concepts on the role of mucins in the protection of corneal and conjunctival epithelia and to identify alterations of mucins in ocular surface diseases. RECENT FINDINGS New evidence indicates that gel-forming and cell surface-associated mucins contribute differently to the protection of the ocular surface against allergens, pathogens, extracellular molecules, abrasive stress, and drying. SUMMARY Mucins are high-molecular weight glycoproteins characterized by their extensive O-glycosylation. Major mucins expressed by the ocular surface epithelia include cell surface-associated mucins MUC1, MUC4, MUC16, and the gel-forming mucin MUC5AC. Recent advances using functional assays have allowed the examination of their roles in the protection of corneal and conjunctival epithelia. Alterations in mucin and mucin O-glycan biosynthesis in ocular surface disorders, including allergy, nonautoimmune dry eye, autoimmune dry eye, and infection, are presented.
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Mantelli F, Schaffer L, Dana R, Head SR, Argüeso P. Glycogene expression in conjunctiva of patients with dry eye: downregulation of Notch signaling. Invest Ophthalmol Vis Sci 2008; 50:2666-72. [PMID: 19011014 DOI: 10.1167/iovs.08-2734] [Citation(s) in RCA: 52] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
PURPOSE Glycoconjugates regulate a variety of biological events in mucosal surfaces, such as differentiation of postmitotic epithelial cells and maintenance of the wet-surfaced phenotype. This study aimed to identify the repertoire of genes (glycogenes) involved in biosynthesis of glycoconjugates in conjunctiva of normal subjects and patients with dry eye. METHODS RNA from conjunctival impression cytology samples was amplified and hybridized to a custom-designed glycogene microarray. Intensity data were converted to expression values and analyzed by ANOVA. Microarray data for selected Notch glycogenes were confirmed by quantitative real-time PCR. Notch receptors and ligands were immunolocalized on conjunctival biopsies by confocal microscopy. RESULTS By microarray, 424 glycogenes were identified in normal conjunctival epithelium; galectins, glycosyltransferases, mucins, Notch signaling molecules, and proteoglycans were among the most highly expressed. In dry eye, 46 glycogenes were significantly downregulated, including five members of the Notch signaling pathway (Notch1, Notch 2, Notch 3, Jagged1, Delta1), four Wnt signaling molecules (Wnt4, -5A, Frizzled6, -7), and three heparan sulfate glycotransferases (HS2ST1, HS3ST6, EXTL2). Only interferon-induced transmembrane protein 1 was upregulated. By real-time PCR, expression ratios of Notch1, Notch 3, and Jagged1 in dry eye were 0.43, 0.56, and 0.50, respectively, compared to controls (P < 0.05). Notch1, Notch3, and Jagged1 were immunolocalized throughout the conjunctival epithelium, whereas Notch2 and Delta1 were distributed apically. CONCLUSIONS This study revealed the differential glycogene expression profiles in normal subjects and patients with dry eye. Downregulation of Notch signaling in dry eye may result in abnormal differentiation of the conjunctival epithelium and have implications in the pathogenesis of the disease.
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Affiliation(s)
- Flavio Mantelli
- Department of Ophthalmology, Schepens Eye Research Institute, Harvard Medical School, Boston, Massachusetts 02114, USA
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Hori Y, Sugiyama H, Soma T, Nishida K. Expression of Membrane-associated Mucins in Cultivated Human Oral Mucosal Epithelial Cells. Cornea 2007; 26:S65-9. [PMID: 17881919 DOI: 10.1097/ico.0b013e31812f6c95] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
PURPOSE Membrane-associated mucins present in the cells of the ocular surface epithelium (MUC1, -4, and -16) are believed to contribute to the maintenance of the health and wet surface of epithelial cells. Recent studies have reported the use of cultivated oral mucosal epithelial sheet transplantation for reconstruction of the ocular surface. We studied the expression of membrane-associated mucins in cultivated human oral mucosal epithelial sheets and compared it with that in human ocular surface epithelial cells. METHODS Specimens (3 x 3 mm) of oral mucosal tissue were harvested from healthy volunteers. The oral mucosal epithelial cells obtained from the specimens, the corneal epithelial cells, or an oral mucosal cell line (KB cells) were cultured together with mitomycin C-treated 3T3 feeder cells on temperature-responsive culture surfaces for 2 weeks to produce stratified cell sheets. Reverse transcriptase-polymerase chain reaction was used to determine the expression of membrane-associated mucins (MUC1, -3, -4, -12, -13, -15, -16, and -17) in these cells. RESULTS MUC1, -4, and -16 but not -3, -12, -13, -15, or -17 mRNA was detected in the oral mucosal epithelial sheet and in the corneal epithelial sheet. KB cells, although unable to produce a stratified cell sheet, showed expression of MUC1, -12, -13, and -16 mRNA. CONCLUSIONS The membrane-associated mucins of the ocular surface, MUC1, -4, and -16, are expressed in human oral mucosal epithelial sheets and corneal epithelium. These membrane-associated mucins may therefore contribute to ocular surface reconstruction after oral mucosal epithelial sheet transplantation for patients with severe ocular surface disorders.
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Affiliation(s)
- Yuichi Hori
- Department of Ophthalmology, Osaka University Medical School, Suita 565-0871, Japan.
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Gipson IK, Hori Y, Argüeso P. Character of ocular surface mucins and their alteration in dry eye disease. Ocul Surf 2007; 2:131-48. [PMID: 17216084 DOI: 10.1016/s1542-0124(12)70149-0] [Citation(s) in RCA: 140] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
At the ocular surface, three types of mucins are present. The large gel-forming mucin MUC5AC is expressed by conjunctival goblet cells. Some cells of the lacrimal gland acini express the small soluble mucin MUC7. The corneal and conjunctival epithelia express the membrane-associated mucins MUCs 1, 4, and 16. With the characterization of the mucin gene repertoire of the ocular surface epithelia, studies of the function of specific mucins, their gene regulation, and their alteration in ocular surface disease have begun. Current information suggests that all the mucins are hydrophilic and play a role in maintenance of water on the surface of the eye. The large secreted mucins represent the "janitorial service" that moves over the surface of the eye to wrap up and remove debris. The membrane-associated mucins form the glycocalyx, which provides a continuous barrier across the surface of the eye that prevents pathogen penetrance and has signaling capabilities that influence epithelial activity. Factors regulating mucin gene expression include retinoic acid, serum, and dexamethasone. Alteration in both secreted and membrane-associated mucins occur in drying ocular surface diseases. In Sjogren syndrome, MUC5AC expression is reduced, and in non-Sjogren dry eye, glycosylation of MUC16 appears to be altered. The pattern of expression of enzymes that glycosylate mucins is altered in ocular cicatricial pemphigoid. Therapies being evaluated for dry eye, including cyclosporine A, P2Y2 agonists, gefarnate, 15-(S)-HETE, and corticosteroids, may be efficacious due to their effect on mucin gene expression and secretion.
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Affiliation(s)
- Ilene K Gipson
- Schepens Eye Research Institute and Department of Ophthalmology, Harvard Medical School, Boston, Massachusetts 02114, USA.
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Abstract
Members of the DEWS Research Subcommittee reviewed research into the basic mechanisms underlying dry eye disease. Evidence was evaluated concerning the tear film, lacrimal gland and accessory lacrimal glands, ocular surface epithelia (including cornea and conjunctiva), meibomian glands, lacrimal duct system and the immune system. Consideration was given to both animal and human research data. Results are presented as a series of information matrices, identifying what is known and providing supporting references. An attempt is made to identify areas for further investigation.
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Nakamura Y, Yokoi N, Tokushige H, Kinoshita S. Sialic acid in normal and dry eye tear fluid. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2003; 506:347-51. [PMID: 12613932 DOI: 10.1007/978-1-4615-0717-8_50] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Affiliation(s)
- Yo Nakamura
- Department of Ophthalmology, Kyoto Prefectural University of Medicine, Kyoto, Japan
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Garcher C, Bron A, Baudouin C, Bildstein L, Bara J. CA 19-9 ELISA test: a new method for studying mucus changes in tears. Br J Ophthalmol 1998; 82:88-90. [PMID: 9536889 PMCID: PMC1722341 DOI: 10.1136/bjo.82.1.88] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
AIMS This study investigated mucus changes in the tears in various eye conditions using impression cytology. The quantity of mucins was measured by enzyme linked immunosorbent assay (ELISA) using the tumour marker CA 19-9. This assay quantifies the sialylated Lewis(a) structure mainly associated with ocular mucins. METHODS Impression cytology was performed using a cellulose nitrate membrane, on 53 healthy patients, 50 glaucoma patients treated with beta blockers, 24 patients suffering from dry eye syndrome, and 45 contact lens wearers. The tear film glycoproteins were eluted and CA 19-9 was measured. RESULTS CA 19-9 content expressed as kilo units (kU) per microgram of tears was significantly decreased in dry eye syndrome (25.8 kU (SD 17.3)/microgram) (p < 0.05), glaucoma patients over 60 years (28.9 (19.5) kU/microgram) (p < 0.05), and contact lens wearers (28.4 kU (18)/microgram) (p < 0.05), when compared with healthy individuals (39.4 kU (22.2)/microgram). CONCLUSION Impression cytology can be regarded as a valuable method for obtaining samples of glycoconjugates of mucin. The decrease of sialylated chains observed with this method confirms the hypothesis that some quantitative changes in the tear film may be encountered in ocular surface disorders.
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Affiliation(s)
- C Garcher
- Department of Ophthalmology, CHU Dijon, France
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Corfield AP, Carrington SD, Hicks SJ, Berry M, Ellingham R. Ocular mucins: Purification, metabolism and functions. Prog Retin Eye Res 1997. [PMCID: PMC7128873 DOI: 10.1016/s1350-9462(96)00039-0] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/01/2022]
Abstract
Mucins are present at the ocular surface in both secreted and membrane-bound forms. Mucins are produced in partby the conjunctial goblet cells, and are complemented by non-globet secretions. This review focuses on secreted ocular mucins. They are present in the tear film, probably both in gel and soluble form, and play a role in lubrication and ocular defense. It is apparent that mucins are highly adapted to their functions. State of the art techniques for mucin purification and analysis are presented. Density gradient centrifugation, gel filtration, ion-exchange chromatography and agarose gel electrophoresis are discussed, together with methods of oliogosaccharide analysis. Reagents for the detection of mucin are considered in conjunction with these methods, which we have employed in the analysis of human and canine ocular mucins. The general structure of mucins is reviewed. The biosyntheas and glycosylation of ocular mucins are not yet fully understood, and are discussed in relation to currently established concepts. The impaact of disease on the nature and secretion of mucins is considered, as well as the physiological and pathological significance of mucus degradation.
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Versura P, Maltarello MC, Caramazza R, Laschi R. Mucus alteration and eye dryness. A possible relationship. Acta Ophthalmol 1989; 67:455-64. [PMID: 2801051 DOI: 10.1111/j.1755-3768.1989.tb01632.x] [Citation(s) in RCA: 23] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
From a very early phase we studied 15 patients suffering from a dry-eye condition ant associated to systemic diseases. Conjunctival biopsies were studied in Transmission (TEM) and Scanning (SEM) electron microscopy. Moreover, the lectin-gold cytochemistry at ultrastructural level was applied to investigate the distribution of some glycosidic receptors produced by both the goblet cells and the vesicles belonging to the Second Mucus System (SMS). No evidence of epithelial stratification and only a decrease in the goblet cell population was observed. The SMS vesicles and the superficial cell microvilli did not appear greatly reduced in number. A difference in the mucus composition in terms of content of glycosidic residues was detected in dry-eye patients compared to the normal subjects. The role of the mucus produced by both the goblet cells and the SMS vesicles in debated. A possible correlation between the alteration of the mucus content and the failure of the tear film stability is proposed. On the basis of these data, a new therapeutic approach for eye dryness is suggested.
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Affiliation(s)
- P Versura
- Institute of Clinical Electron Microscopy, University of Bologna, Italy
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Versura P, Maltarello MC. An improved processing method for electron microscopy investigation of conjunctival biopsies. Curr Eye Res 1987; 6:943-6. [PMID: 3621986 DOI: 10.3109/02713688709034863] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
A new schedule in the processing of conjunctival biopsies for ultrastructural investigations is proposed. The specimens are first examined in Scanning Electron Microscopy (SEM), briefly rehydrated and secondly processed for observation in Transmission Electron Microscopy (TEM). The rehydration counterbalances the shrinkage due to the previous processing steps applied for SEM examination and allows a good TEM morphology of the recovered specimens to be achieved. The correlative SEM/TEM study on the same conjunctival biopsy provides complete informations on both the surface and the inner structure of the tissue. This appears of value in the investigation of conjunctival biopsy from eyes affected by tear film quantitative and/or qualitative alterations.
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