{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,5,22]],"date-time":"2026-05-22T18:06:29Z","timestamp":1779473189578,"version":"3.53.1"},"reference-count":35,"publisher":"Public Library of Science (PLoS)","issue":"5","license":[{"start":{"date-parts":[[2026,5,22]],"date-time":"2026-05-22T00:00:00Z","timestamp":1779408000000},"content-version":"vor","delay-in-days":0,"URL":"http:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/100010010","name":"Glasgow Caledonian University","doi-asserted-by":"publisher","id":[{"id":"10.13039\/100010010","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":["www.plosone.org"],"crossmark-restriction":false},"short-container-title":["PLoS One"],"abstract":"<jats:sec id=\"sec001\">\n                    <jats:title>Purpose<\/jats:title>\n                    <jats:p>\n                      Demodex mites act as a carrier vector for the bacterium\n                      <jats:italic>Bacillus oleronius<\/jats:italic>\n                      . Antigenic proteins from this bacterium are capable of producing an inflammatory response. This study investigated the potential effects of Demodex spp.-associated\n                      <jats:italic>Bacillus oleronius<\/jats:italic>\n                      proteins and dry eye-induced hyperosmolarity on an immortalised human conjunctival epithelial (Chang) cell line.\n                    <\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec id=\"sec002\">\n                    <jats:title>Methods<\/jats:title>\n                    <jats:p>\n                      The Wong Kilbourne derivative of the Chang (WKD) HeLa-modified conjunctiva-derived epithelial cell line was cultured in a series of NaCl-hyperosmolar conditions with various concentrations ranging from 350mOsm\/L to 550mOsm\/L. Chang cells were then exposed to semi-purified\n                      <jats:italic>B.oleronius<\/jats:italic>\n                      proteins at 2 \u00b5g and 6 \u00b5g either alone or in conjunction with dry eye-induced hyperosmolar (HO) stress at 2 \u00b5g\u2009+\u2009HO500 mOsm\/L and 6 \u00b5g\u2009+\u2009HO500 mOsm\/L. The cell viability was assessed with the RealTime-Glo MT cell viability assay.\n                    <\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec id=\"sec003\">\n                    <jats:title>Results<\/jats:title>\n                    <jats:p>\n                      Compared to controls, the cell viability appeared to decrease in a dose-dependent manner. B.\n                      <jats:italic>oleronius<\/jats:italic>\n                      concentration at 6 \u00b5g showed significantly lower cell viability than both controls (p\u2009&lt;\u20090.001) and 2 \u00b5g (p\u2009&lt;\u20090.001). When 500mOsm\/L was added to the 2 \u00b5g and 6 \u00b5g concentrations, the lowest cell viability was observed (p\u2009&lt;\u20090.001). At 24 hours, the\n                      <jats:italic>B.oleronius<\/jats:italic>\n                      2 \u03bcg combined with HO500 resulted in 38% viable cells, compared to 81% viability in\n                      <jats:italic>B.oleronius<\/jats:italic>\n                      2 \u03bcg alone (p\u2009&lt;\u20090.001). Similarly, the\n                      <jats:italic>B.oleronius<\/jats:italic>\n                      6 \u03bcg combined with HO500 showed only 23% metabolising cells compared to 60% viability cells in\n                      <jats:italic>B.oleronius<\/jats:italic>\n                      6 \u03bcg alone (p\u2009&lt;\u20090.001).\n                    <\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec id=\"sec004\">\n                    <jats:title>Conclusion<\/jats:title>\n                    <jats:p>\n                      The results suggest that the presence of bacterial proteins and hyperosmolarity have a dose and time-dependent effect on cellular viability. These experiments suggest that patients affected with the comorbidity of dry eye disease and\n                      <jats:italic>Demodex<\/jats:italic>\n                      blepharitis could experience more severe signs than those with\n                      <jats:italic>Demodex-<\/jats:italic>\n                      associated blepharitis alone.\n                    <\/jats:p>\n                  <\/jats:sec>","DOI":"10.1371\/journal.pone.0350103","type":"journal-article","created":{"date-parts":[[2026,5,22]],"date-time":"2026-05-22T17:39:34Z","timestamp":1779471574000},"page":"e0350103","update-policy":"https:\/\/doi.org\/10.1371\/journal.pone.corrections_policy","source":"Crossref","is-referenced-by-count":0,"title":["The effect of Demodex-associated Bacillus oleronius proteins and hyperosmolarity on a human conjunctival epithelial cell line"],"prefix":"10.1371","volume":"21","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-8851-9891","authenticated-orcid":true,"given":"Nikhil","family":"Sharma","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Eilidh","family":"Martin","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Edward Ian","family":"Pearce","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Suzanne","family":"Hagan","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"340","published-online":{"date-parts":[[2026,5,22]]},"reference":[{"issue":"2","key":"pone.0350103.ref001","first-page":"1021","article-title":"Conjunctival flora of normal human eye.","volume":"2","author":"PR Sthapit","year":"2014","journal-title":"JSM Ophthalmol"},{"issue":"4","key":"pone.0350103.ref002","doi-asserted-by":"crossref","first-page":"254","DOI":"10.1097\/ICL.0000000000000697","article-title":"Next-generation sequencing of the ocular surface microbiome: in health, contact lens wear, diabetes, trachoma, and dry eye","volume":"46","author":"A Okonkwo","year":"2020","journal-title":"Eye Contact Lens"},{"issue":"1","key":"pone.0350103.ref003","doi-asserted-by":"crossref","first-page":"24296","DOI":"10.1038\/s41598-021-03801-y","article-title":"Effect of ocular demodicosis on the stability of the tear film and the tear break up time","volume":"11","author":"A S\u0119dzikowska","year":"2021","journal-title":"Sci Rep"},{"key":"pone.0350103.ref004","doi-asserted-by":"crossref","first-page":"57","DOI":"10.2147\/OPTO.S142708","article-title":"Demodexblepharitis: clinical perspectives","volume":"10","author":"S Fromstein","year":"2018","journal-title":"Clin Optom (Auckl)"},{"issue":"8","key":"pone.0350103.ref005","doi-asserted-by":"crossref","first-page":"699","DOI":"10.1139\/m95-096","article-title":"Bacillus oleronius sp.nov., a member of the hindgut flora of the termite Reticulitermes santonensis (Feytaud)","volume":"41","author":"T Kuhnigk","year":"1995","journal-title":"Can J Microbiol"},{"issue":"3","key":"pone.0350103.ref006","doi-asserted-by":"crossref","first-page":"474","DOI":"10.1111\/j.1365-2133.2007.08028.x","article-title":"Mite-related bacterial antigens stimulate inflammatory cells in rosacea","volume":"157","author":"N Lacey","year":"2007","journal-title":"Br J Dermatol"},{"issue":"5","key":"pone.0350103.ref007","article-title":"Correlation between ocular Demodex infestation and serum immunoreactivity to Bacillus proteins in patients with Facial rosacea","volume":"117","author":"J Li","year":"2010","journal-title":"Ophthalmology"},{"key":"pone.0350103.ref008","doi-asserted-by":"crossref","first-page":"31","DOI":"10.1016\/j.jtos.2021.12.010","article-title":"Reconsidering the pathogenesis of chalazion","volume":"24","author":"T Suzuki","year":"2022","journal-title":"Ocul Surf"},{"issue":"4","key":"pone.0350103.ref009","doi-asserted-by":"crossref","first-page":"777","DOI":"10.1515\/ap-2015-0110","article-title":"Demodex mites as potential etiological factor in chalazion - 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