{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,30]],"date-time":"2026-09-30T14:21:07Z","timestamp":1790778067991,"version":"4.1.0"},"reference-count":42,"publisher":"MDPI AG","issue":"4","license":[{"start":{"date-parts":[[2018,4,17]],"date-time":"2018-04-17T00:00:00Z","timestamp":1523923200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["IJMS"],"abstract":"<jats:p>Dry eye symptoms are among the leading complaints in ophthalmology. Dry eye disease (DED) is associated with significant pain affecting quality of life. Cellular and molecular mechanisms underlying ocular pain associated with DED are not fully understood. In this study, we investigated the ocular surface of patients with DED using in vivo confocal microscopy (IVCM) to quantify corneal nerve density and its relation with corneal inflammation. Gene expression of the proinflammatory markers HLA-DR, IL-6, CXCL12, and CCL2 and the receptors CXCR4 and CCR2, as well as PENK (enkephalin precursor), was therefore quantified in conjunctival impression cytology specimens. Thirty-two patients with DED and 15 age-matched controls were included. Subbasal nerve density was significantly lower in DED patients compared to controls. IVCM analysis revealed that DED patients had a significantly higher corneal dendritic cell density compared to controls. Conjunctival impression cytology analysis revealed that HLA-DR, IL-6, CXCR4, and CCL2\/CCR2 mRNA levels were significantly increased in DED patients compared to controls, whereas PENK mRNA levels were significantly decreased. Similar results were obtained in vitro on immortalized human conjunctiva-derived epithelial cells challenged with osmotic stress that mimics the DED condition. These results demonstrate that proinflammatory molecules and endogenous enkephalin have opposite gene regulation during DED.<\/jats:p>","DOI":"10.3390\/ijms19041221","type":"journal-article","created":{"date-parts":[[2018,4,18]],"date-time":"2018-04-18T03:51:13Z","timestamp":1524023473000},"page":"1221","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":62,"title":["Proinflammatory Markers, Chemokines, and Enkephalin in Patients Suffering from Dry Eye Disease"],"prefix":"10.3390","volume":"19","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-3283-9738","authenticated-orcid":false,"given":"Pierre","family":"Nicolle","sequence":"first","affiliation":[{"name":"Department of Ophthalmology III, Quinze-Vingts National Ophthalmology Hospital, F-75012 Paris, France"},{"name":"Quinze-Vingts National Ophthalmology Hospital, DHU Sight Restore, INSERM-DGOS CIC 1423, F-75012 Paris, France"},{"name":"Sorbonne Universit\u00e9, INSERM, CNRS, Institut de la Vision, F-75012 Paris, France"},{"name":"Department of Ophthalmology, Ambroise Par\u00e9 Hospital, APHP, University of Versailles Saint-Quentin en Yvelines, F-92100 Boulogne-Billancourt, France"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Hong","family":"Liang","sequence":"additional","affiliation":[{"name":"Department of Ophthalmology III, Quinze-Vingts National Ophthalmology Hospital, F-75012 Paris, France"},{"name":"Quinze-Vingts National Ophthalmology Hospital, DHU Sight Restore, INSERM-DGOS CIC 1423, F-75012 Paris, France"},{"name":"Sorbonne Universit\u00e9, INSERM, CNRS, Institut de la Vision, F-75012 Paris, France"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9264-1133","authenticated-orcid":false,"given":"Elodie","family":"Reboussin","sequence":"additional","affiliation":[{"name":"Sorbonne Universit\u00e9, INSERM, CNRS, Institut de la Vision, F-75012 Paris, France"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ghislaine","family":"Rabut","sequence":"additional","affiliation":[{"name":"Department of Ophthalmology III, Quinze-Vingts National Ophthalmology Hospital, F-75012 Paris, France"},{"name":"Quinze-Vingts National Ophthalmology Hospital, DHU Sight Restore, INSERM-DGOS CIC 1423, F-75012 Paris, France"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Elise","family":"Warcoin","sequence":"additional","affiliation":[{"name":"Sorbonne Universit\u00e9, INSERM, CNRS, Institut de la Vision, F-75012 Paris, France"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Fran\u00e7oise","family":"Brignole-Baudouin","sequence":"additional","affiliation":[{"name":"Sorbonne Universit\u00e9, INSERM, CNRS, Institut de la Vision, F-75012 Paris, France"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"St\u00e9phane","family":"Melik-Parsadaniantz","sequence":"additional","affiliation":[{"name":"Sorbonne Universit\u00e9, INSERM, CNRS, Institut de la Vision, F-75012 Paris, France"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1743-6698","authenticated-orcid":false,"given":"Christophe","family":"Baudouin","sequence":"additional","affiliation":[{"name":"Department of Ophthalmology III, Quinze-Vingts National Ophthalmology Hospital, F-75012 Paris, France"},{"name":"Quinze-Vingts National Ophthalmology Hospital, DHU Sight Restore, INSERM-DGOS CIC 1423, F-75012 Paris, France"},{"name":"Sorbonne Universit\u00e9, INSERM, CNRS, Institut de la Vision, F-75012 Paris, France"},{"name":"Department of Ophthalmology, Ambroise Par\u00e9 Hospital, APHP, University of Versailles Saint-Quentin en Yvelines, F-92100 Boulogne-Billancourt, France"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Antoine","family":"Labbe","sequence":"additional","affiliation":[{"name":"Department of Ophthalmology III, Quinze-Vingts National Ophthalmology Hospital, F-75012 Paris, France"},{"name":"Quinze-Vingts National Ophthalmology Hospital, DHU Sight Restore, INSERM-DGOS CIC 1423, F-75012 Paris, France"},{"name":"Sorbonne Universit\u00e9, INSERM, CNRS, Institut de la Vision, F-75012 Paris, France"},{"name":"Department of Ophthalmology, Ambroise Par\u00e9 Hospital, APHP, University of Versailles Saint-Quentin en Yvelines, F-92100 Boulogne-Billancourt, France"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3855-9523","authenticated-orcid":false,"given":"Annabelle","family":"Reaux-Le Goazigo","sequence":"additional","affiliation":[{"name":"Sorbonne Universit\u00e9, INSERM, CNRS, Institut de la Vision, F-75012 Paris, 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