{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,3]],"date-time":"2026-03-03T11:36:29Z","timestamp":1772537789856,"version":"3.50.1"},"reference-count":27,"publisher":"Springer Science and Business Media LLC","issue":"5","license":[{"start":{"date-parts":[[2021,1,14]],"date-time":"2021-01-14T00:00:00Z","timestamp":1610582400000},"content-version":"tdm","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0"},{"start":{"date-parts":[[2021,1,14]],"date-time":"2021-01-14T00:00:00Z","timestamp":1610582400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0"}],"funder":[{"name":"Projekt DEAL"}],"content-domain":{"domain":["link.springer.com"],"crossmark-restriction":false},"short-container-title":["Graefes Arch Clin Exp Ophthalmol"],"published-print":{"date-parts":[[2021,5]]},"abstract":"<jats:title>Abstract<\/jats:title><jats:sec>\n                <jats:title>Purpose<\/jats:title>\n                <jats:p>To analyze the effect of riboflavin UV-A illumination on mRNA and protein expression of healthy (HCFs) and keratoconus human corneal fibroblasts (KC-HCFs), concerning the inflammatory markers NF-\u03baB, iNOS, IL-6, and collagen 1 and 5 (Col 1\/Col 5).<\/jats:p>\n              <\/jats:sec><jats:sec>\n                <jats:title>Methods<\/jats:title>\n                <jats:p>Keratocytes were isolated from healthy (<jats:italic>n<\/jats:italic> = 3) and keratoconus (KC) corneas (<jats:italic>n<\/jats:italic> = 3) and were cultivated in basal medium with 5% fetal calf serum, which resulted in their transformation into human corneal fibroblasts (HCFs\/KC-HCFs). Cells underwent 0.1% riboflavin UV-A illumination for 250 s (CXL). NF-\u03baB, iNOS, IL-6, Col 1, and Col 5 expression was investigated by qPCR and Western blot analysis. IL-6 concentration of the cell culture supernatant and cell lysate was determined by ELISA.<\/jats:p>\n              <\/jats:sec><jats:sec>\n                <jats:title>Results<\/jats:title>\n                <jats:p>In untreated KC-HCFs, NF-\u03baB (<jats:italic>p<\/jats:italic> = 0.0002), iNOS (<jats:italic>p<\/jats:italic> = 0.0019), Col 1 (<jats:italic>p<\/jats:italic> = 0.0286), and Col 5 (<jats:italic>p<\/jats:italic> = 0.0054) mRNA expression was higher and IL-6 expression was lower (<jats:italic>p<\/jats:italic> = 0.0057), than in healthy controls. In HCFs, CXL led to an increased NF-\u03baB (<jats:italic>p<\/jats:italic> = 0.0286) and IL-6 (<jats:italic>p<\/jats:italic> = 0.0057) mRNA expression. The IL-6 concentration in the cell culture supernatant was increased in HCFs (<jats:italic>p<\/jats:italic> = 0.0485) and KC-HCFs (<jats:italic>p<\/jats:italic> = 0.0485) after CXL. CXL increased intracellular IL-6 concentration only in KC-HCFs (<jats:italic>p<\/jats:italic> = 0.0357). In the HCF group (<jats:italic>p<\/jats:italic> = 0.0286), an increased Col 1 mRNA expression after CXL could be observed.<\/jats:p>\n              <\/jats:sec><jats:sec>\n                <jats:title>Conclusion<\/jats:title>\n                <jats:p>Our study confirmed altered gene expression in untreated KC-HCFs compared to untreated HCFs. Riboflavin UV-A illumination affected gene expression only in HCFs. Increased IL-6 concentration in the cell culture supernatant and cell lysate indicate a secondary inflammatory response of HCFs and KC-HCFs to riboflavin UV-A illumination.<\/jats:p>\n              <\/jats:sec>","DOI":"10.1007\/s00417-020-05058-z","type":"journal-article","created":{"date-parts":[[2021,1,14]],"date-time":"2021-01-14T10:03:43Z","timestamp":1610618623000},"page":"1225-1234","update-policy":"https:\/\/doi.org\/10.1007\/springer_crossmark_policy","source":"Crossref","is-referenced-by-count":13,"title":["NF-\u03baB, iNOS, IL-6, and collagen 1 and 5 expression in healthy and keratoconus corneal fibroblasts after 0.1% riboflavin UV-A illumination"],"prefix":"10.1007","volume":"259","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-2307-2237","authenticated-orcid":false,"given":"Tim","family":"Berger","sequence":"first","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"N\u00f3ra","family":"Szentm\u00e1ry","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Lorenz","family":"Latta","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Berthold","family":"Seitz","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Tanja","family":"Stachon","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"297","published-online":{"date-parts":[[2021,1,14]]},"reference":[{"key":"5058_CR1","doi-asserted-by":"publisher","first-page":"921","DOI":"10.1016\/j.ajo.2014.01.017","volume":"157","author":"JC Fan Gaskin","year":"2014","unstructured":"Fan Gaskin JC, Patel DV, McGhee CNJ (2014) Acute corneal hydrops in keratoconus - new perspectives. Am J Ophthalmol 157:921\u2013928. https:\/\/doi.org\/10.1016\/j.ajo.2014.01.017","journal-title":"Am J Ophthalmol"},{"key":"5058_CR2","doi-asserted-by":"publisher","first-page":"297","DOI":"10.1016\/S0039-6257(97)00119-7","volume":"42","author":"YS Rabinowitz","year":"1998","unstructured":"Rabinowitz YS (1998) Keratoconus. Surv Ophthalmol 42:297\u2013319. https:\/\/doi.org\/10.1016\/S0039-6257(97)00119-7","journal-title":"Surv Ophthalmol"},{"key":"5058_CR3","doi-asserted-by":"publisher","first-page":"169","DOI":"10.1016\/j.ajo.2016.12.015","volume":"175","author":"DA Godefrooij","year":"2017","unstructured":"Godefrooij DA, de Wit GA, Uiterwaal CS et al (2017) Age-specific incidence and prevalence of keratoconus: a nationwide registration study. Am J Ophthalmol 175:169\u2013172. https:\/\/doi.org\/10.1016\/j.ajo.2016.12.015","journal-title":"Am J Ophthalmol"},{"key":"5058_CR4","doi-asserted-by":"publisher","first-page":"924","DOI":"10.1038\/sj.eye.6701677","volume":"19","author":"I Cozma","year":"2005","unstructured":"Cozma I, Atherley C, James N (2005) Influence of ethnic origin on the incidence of keratoconus and associated atopic disease in Asian and white patients. Eye (Lond) 19:924\u2013925. https:\/\/doi.org\/10.1038\/sj.eye.6701677","journal-title":"Eye (Lond)"},{"key":"5058_CR5","doi-asserted-by":"publisher","first-page":"157","DOI":"10.1016\/j.clae.2010.04.006","volume":"33","author":"M Romero-Jim\u00e9nez","year":"2010","unstructured":"Romero-Jim\u00e9nez M, Santodomingo-Rubido J, Wolffsohn JS (2010) Keratoconus: a review. Contact Lens Anterior Eye 33:157\u2013166. https:\/\/doi.org\/10.1016\/j.clae.2010.04.006","journal-title":"Contact Lens Anterior Eye"},{"key":"5058_CR6","doi-asserted-by":"publisher","unstructured":"Stachon T, Latta L, Kolev K et al (2019) Increased NF-\u03baB and iNOS expression in keratoconus keratocytes - hints for an inflammatory component? Klin Monbl Augenheilkd. https:\/\/doi.org\/10.1055\/a-1002-0100","DOI":"10.1055\/a-1002-0100"},{"key":"5058_CR7","doi-asserted-by":"publisher","first-page":"654","DOI":"10.1016\/j.ophtha.2004.11.050","volume":"112","author":"I Lema","year":"2005","unstructured":"Lema I, Dur\u00e1n JA (2005) Inflammatory molecules in the tears of patients with keratoconus. Ophthalmology 112:654\u2013659. https:\/\/doi.org\/10.1016\/j.ophtha.2004.11.050","journal-title":"Ophthalmology"},{"key":"5058_CR8","doi-asserted-by":"publisher","first-page":"4608","DOI":"10.1038\/srep04608","volume":"4","author":"D Karamichos","year":"2014","unstructured":"Karamichos D, Hutcheon A, Rich C et al (2014) In vitro model suggests oxidative stress involved in keratoconus disease. Sci Rep 4:4608. https:\/\/doi.org\/10.1038\/srep04608","journal-title":"Sci Rep"},{"key":"5058_CR9","doi-asserted-by":"publisher","first-page":"1","DOI":"10.1016\/j.exer.2015.01.007","volume":"132","author":"D Karamichos","year":"2015","unstructured":"Karamichos D, Zieske J, Sejersen H et al (2015) Tear metabolite changes in keratoconus. Exp Eye Res 132:1\u20138. https:\/\/doi.org\/10.1016\/j.exer.2015.01.007","journal-title":"Exp Eye Res"},{"key":"5058_CR10","doi-asserted-by":"publisher","first-page":"326","DOI":"10.1016\/j.exer.2010.06.021","volume":"91","author":"J Hassell","year":"2010","unstructured":"Hassell J, Birk D (2010) The molecular basis of corneal transparency. Exp Eye Res 91:326\u2013335. https:\/\/doi.org\/10.1016\/j.exer.2010.06.021","journal-title":"Exp Eye Res"},{"key":"5058_CR11","doi-asserted-by":"publisher","first-page":"423","DOI":"10.1016\/j.exer.2006.10.014","volume":"84","author":"S Hayes","year":"2007","unstructured":"Hayes S, Boote C, Tuft S et al (2007) A study of corneal thickness, shape and collagen organisation in keratoconus using videokeratography and X-ray scattering techniques. Exp Eye Res 84:423\u2013434. https:\/\/doi.org\/10.1016\/j.exer.2006.10.014","journal-title":"Exp Eye Res"},{"key":"5058_CR12","doi-asserted-by":"publisher","first-page":"1","DOI":"10.1038\/s41598-019-56529-1","volume":"9","author":"A Alkanaan","year":"2019","unstructured":"Alkanaan A, Barsotti R, Kirat O et al (2019) Collagen fibrils and proteoglycans of peripheral and central stroma of the keratoconus cornea - ultrastructure and 3D transmission electron tomography. Sci Rep 9:1\u201311. https:\/\/doi.org\/10.1038\/s41598-019-56529-1","journal-title":"Sci Rep"},{"key":"5058_CR13","doi-asserted-by":"publisher","first-page":"459","DOI":"10.1016\/j.survophthal.2015.02.004","volume":"60","author":"JS Parker","year":"2015","unstructured":"Parker JS, van Dijk K, Melles GRJ (2015) Treatment options for advanced keratoconus: a review. Surv Ophthalmol 60:459\u2013480. https:\/\/doi.org\/10.1016\/j.survophthal.2015.02.004","journal-title":"Surv Ophthalmol"},{"key":"5058_CR14","doi-asserted-by":"publisher","first-page":"65","DOI":"10.1016\/j.jtos.2013.01.002","volume":"11","author":"F Raiskup","year":"2013","unstructured":"Raiskup F, Spoerl E (2013) Corneal crosslinking with riboflavin and ultraviolet A. I. principles. Ocul Surf 11:65\u201374. https:\/\/doi.org\/10.1016\/j.jtos.2013.01.002","journal-title":"Ocul Surf"},{"key":"5058_CR15","doi-asserted-by":"publisher","first-page":"148","DOI":"10.1007\/s12094-008-0172-2","volume":"10","author":"A Juarranz","year":"2008","unstructured":"Juarranz A, Ja\u00e9n P, Sanz-Rodriguez F, Cuevas-Santos J (2008) Photodynamic therapy of cancer. Basic principles and applications. Clin Transl Oncol 10:148\u2013154. https:\/\/doi.org\/10.1007\/s12094-008-0172-2","journal-title":"Basic principles and applications. Clin Transl Oncol"},{"key":"5058_CR16","doi-asserted-by":"publisher","first-page":"620","DOI":"10.1016\/S0002-9394(02)02220-1","volume":"135","author":"G Wollensak","year":"2003","unstructured":"Wollensak G, Spoerl E, Seiler T (2003) Riboflavin\/ultraviolet-A-induced collagen crosslinking for the treatment of keratoconus. Am J Ophthalmol 135:620\u2013627. https:\/\/doi.org\/10.1016\/S0002-9394(02)02220-1","journal-title":"Am J Ophthalmol"},{"key":"5058_CR17","doi-asserted-by":"publisher","first-page":"254237","DOI":"10.1155\/2015\/254237","volume":"2015","author":"X Song","year":"2015","unstructured":"Song X, Stachon T, Wang J et al (2015) Viability, apoptosis, proliferation, activation, and cytokine secretion of human keratoconus keratocytes after cross-linking. Biomed Res Int 2015:254237. https:\/\/doi.org\/10.1155\/2015\/254237","journal-title":"Biomed Res Int"},{"key":"5058_CR18","doi-asserted-by":"publisher","unstructured":"Stachon T, Latta L, Seitz B, Szentm\u00e1ry N (2020) Hypoxic stress increases NF-\u03baB and iNOS mRNA expression in normal, but not in keratoconus corneal fibroblasts. Graefe\u2019s Arch Clin Exp Ophthalmol. https:\/\/doi.org\/10.1007\/s00417-020-04900-8","DOI":"10.1007\/s00417-020-04900-8"},{"key":"5058_CR19","doi-asserted-by":"publisher","first-page":"775","DOI":"10.1016\/j.bbagrm.2010.05.004","volume":"1799","author":"SC Gupta","year":"2010","unstructured":"Gupta SC, Sundaram C, Reuter S, Aggarwal BB (2010) Inhibiting NF-\u03baB activation by small molecules as a therapeutic strategy. Biochim Biophys Acta - Gene Regul Mech 1799:775\u2013787. https:\/\/doi.org\/10.1016\/j.bbagrm.2010.05.004","journal-title":"Biochim Biophys Acta - Gene Regul Mech"},{"key":"5058_CR20","doi-asserted-by":"publisher","first-page":"2327","DOI":"10.1128\/mcb.10.5.2327","volume":"10","author":"TA Libermann","year":"1990","unstructured":"Libermann TA, Baltimore D (1990) Activation of interleukin-6 gene expression through the NF-kappa B transcription factor. Mol Cell Biol 10:2327\u20132334. https:\/\/doi.org\/10.1128\/mcb.10.5.2327","journal-title":"Mol Cell Biol"},{"key":"5058_CR21","doi-asserted-by":"publisher","first-page":"1442","DOI":"10.1128\/IAI.71.3.1442-1452.2003","volume":"71","author":"KR Morris","year":"2003","unstructured":"Morris KR, Lutz RD, Choi HS et al (2003) Role of the NF-\u03baB signaling pathway and \u03baB cis-regulatory elements on the IRF-1 and iNOS promoter regions in mycobacterial lipoarabinomannan induction of nitric oxide. Infect Immun 71:1442\u20131452. https:\/\/doi.org\/10.1128\/IAI.71.3.1442-1452.2003","journal-title":"Infect Immun"},{"key":"5058_CR22","doi-asserted-by":"publisher","first-page":"144","DOI":"10.1165\/ajrcmb.26.1.4477","volume":"26","author":"LE Donnelly","year":"2002","unstructured":"Donnelly LE, Barnes PJ (2002) Expression and regulation of inducible nitric oxide synthase from human primary airway epithelial cells. Am J Respir Cell Mol Biol 26:144\u2013151. https:\/\/doi.org\/10.1165\/ajrcmb.26.1.4477","journal-title":"Am J Respir Cell Mol Biol"},{"key":"5058_CR23","doi-asserted-by":"publisher","first-page":"1902","DOI":"10.1167\/iovs.05-0828","volume":"47","author":"M Chwa","year":"2006","unstructured":"Chwa M, Atilano SR, Reddy V et al (2006) Increased stress-induced generation of reactive oxygen species and apoptosis in human keratoconus fibroblasts. Invest Ophthalmol Vis Sci 47:1902\u20131910. https:\/\/doi.org\/10.1167\/iovs.05-0828","journal-title":"Invest Ophthalmol Vis Sci"},{"key":"5058_CR24","doi-asserted-by":"publisher","first-page":"321","DOI":"10.7555\/JBR.29.20130173","volume":"29","author":"T Stachon","year":"2015","unstructured":"Stachon T, Wang J, Song X et al (2015) Impact of crosslinking\/riboflavin-UVA-photodynamic inactivation on viability, apoptosis and activation of human keratocytes in vitro. J Biomed Res 29:321\u2013325. https:\/\/doi.org\/10.7555\/JBR.29.20130173","journal-title":"J Biomed Res"},{"key":"5058_CR25","doi-asserted-by":"publisher","first-page":"111","DOI":"10.1097\/ICO.0b013e31824d701b","volume":"32","author":"E Messmer","year":"2012","unstructured":"Messmer E, Meyer P, Herwig-Carl M et al (2012) Morphological and immunohistochemical changes after corneal cross-linking. Cornea 32:111\u2013117. https:\/\/doi.org\/10.1097\/ICO.0b013e31824d701b","journal-title":"Cornea"},{"key":"5058_CR26","doi-asserted-by":"publisher","first-page":"701","DOI":"10.1055\/s-0042-100626","volume":"233","author":"MW Belin","year":"2016","unstructured":"Belin MW, Duncan JK (2016) Keratoconus: the ABCD Grading System. Klin Monbl Augenheilkd 233:701\u2013707. https:\/\/doi.org\/10.1055\/s-0042-100626","journal-title":"Klin Monbl Augenheilkd"},{"key":"5058_CR27","doi-asserted-by":"publisher","first-page":"12517","DOI":"10.1038\/s41598-017-12598-8","volume":"7","author":"R Sharif","year":"2017","unstructured":"Sharif R, Hjortdal J, Sejersen H et al (2017) Human in vitro model reveals the effects of collagen cross-linking on keratoconus pathogenesis. Sci Rep 7:12517. https:\/\/doi.org\/10.1038\/s41598-017-12598-8","journal-title":"Sci Rep"}],"container-title":["Graefe's Archive for Clinical and Experimental Ophthalmology"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/link.springer.com\/content\/pdf\/10.1007\/s00417-020-05058-z.pdf","content-type":"application\/pdf","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/link.springer.com\/article\/10.1007\/s00417-020-05058-z\/fulltext.html","content-type":"text\/html","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/link.springer.com\/content\/pdf\/10.1007\/s00417-020-05058-z.pdf","content-type":"application\/pdf","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2021,5,6]],"date-time":"2021-05-06T04:15:24Z","timestamp":1620274524000},"score":1,"resource":{"primary":{"URL":"https:\/\/link.springer.com\/10.1007\/s00417-020-05058-z"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2021,1,14]]},"references-count":27,"journal-issue":{"issue":"5","published-print":{"date-parts":[[2021,5]]}},"alternative-id":["5058"],"URL":"https:\/\/doi.org\/10.1007\/s00417-020-05058-z","relation":{},"ISSN":["0721-832X","1435-702X"],"issn-type":[{"value":"0721-832X","type":"print"},{"value":"1435-702X","type":"electronic"}],"subject":[],"published":{"date-parts":[[2021,1,14]]},"assertion":[{"value":"26 August 2020","order":1,"name":"received","label":"Received","group":{"name":"ArticleHistory","label":"Article History"}},{"value":"12 December 2020","order":2,"name":"revised","label":"Revised","group":{"name":"ArticleHistory","label":"Article History"}},{"value":"18 December 2020","order":3,"name":"accepted","label":"Accepted","group":{"name":"ArticleHistory","label":"Article History"}},{"value":"14 January 2021","order":4,"name":"first_online","label":"First Online","group":{"name":"ArticleHistory","label":"Article History"}},{"order":1,"name":"Ethics","group":{"name":"EthicsHeading","label":"Compliance with ethical standards"}},{"value":"The authors declare that they have no conflict of interest.","order":2,"name":"Ethics","group":{"name":"EthicsHeading","label":"Conflict of interest"}},{"value":"This study was performed in accordance with the Declaration of Helsinki and was approved by the Ethics Committee of Saarland\/Germany (No. 41\/18). An informed consent was obtained from all participants with KC, before keratoplasty was performed.","order":3,"name":"Ethics","group":{"name":"EthicsHeading","label":"Ethics approval and consent to participate"}}]}}