{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,25]],"date-time":"2026-03-25T12:17:47Z","timestamp":1774441067262,"version":"3.50.1"},"reference-count":58,"publisher":"MDPI AG","issue":"7","license":[{"start":{"date-parts":[[2026,3,24]],"date-time":"2026-03-24T00:00:00Z","timestamp":1774310400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Delta Dental Research Program to MS","award":["#44-762-54"],"award-info":[{"award-number":["#44-762-54"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["IJMS"],"abstract":"<jats:p>Taste dysfunction, or dysgeusia, is a frequent symptom associated with infections and systemic diseases, yet its cellular and molecular basis remains poorly understood. The COVID-19 pandemic provided an opportunity to study dysgeusia as a \u201cnatural experiment\u201d due to its high prevalence in those with acute and long COVID (LC). We investigated salivary epithelial cells (SECs) using single-cell RNA sequencing to elucidate molecular changes underlying taste dysfunction in LC. Functional enrichment analysis of SEC transcriptomes from individuals with bitter taste dysfunction (LC-D) revealed downregulation of genes involved in cytoskeletal dynamics and taste cell\u2013nerve synapse assembly. Further, specific Type II and III taste receptor genes, critical for bitter taste perception, were reduced. Microbial defense markers such as Toll-like receptors TLR2 and TLR4 were also downregulated, suggesting chronic inflammation. These findings support a model of sustained dysregulated epithelial turnover due to impaired taste in LC-D. Saliva-based single-cell approaches offer promising tools for future diagnostics and mechanistic studies of taste systems.<\/jats:p>","DOI":"10.3390\/ijms27072953","type":"journal-article","created":{"date-parts":[[2026,3,25]],"date-time":"2026-03-25T09:11:14Z","timestamp":1774429874000},"page":"2953","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Single-Cell Transcriptomic Analysis of Salivary Epithelial Cells Reveals Large-Scale Dysregulation in Bitter Taste Dysfunction"],"prefix":"10.3390","volume":"27","author":[{"given":"Shveta","family":"Jaishankar","sequence":"first","affiliation":[{"name":"Department of Oral Pathology, Medicine and Radiology, Indiana University School of Dentistry, Indianapolis, IN 46202, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0009-0003-6374-7478","authenticated-orcid":false,"given":"David","family":"Schaeper","sequence":"additional","affiliation":[{"name":"Department of Biomedical Engineering and Informatics, Luddy School of Informatics, Computing and Engineering, Indiana University Indianapolis, 535 West Michigan Street, Indianapolis, IN 46202, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7351-6268","authenticated-orcid":false,"given":"Sarath Chandra","family":"Janga","sequence":"additional","affiliation":[{"name":"Department of Biomedical Engineering and Informatics, Luddy School of Informatics, Computing and Engineering, Indiana University Indianapolis, 535 West Michigan Street, Indianapolis, IN 46202, USA"},{"name":"Center for Computational Biology and Bioinformatics, Indiana University School of Medicine, 5021 Health Information and Translational Sciences (HITS), 410 West 10th Street, Indianapolis, IN 46202, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Mythily","family":"Srinivasan","sequence":"additional","affiliation":[{"name":"Department of Oral Pathology, Medicine and Radiology, Indiana University School of Dentistry, Indianapolis, IN 46202, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2026,3,24]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"303","DOI":"10.1016\/B978-0-444-63855-7.00019-8","article-title":"Neurolocalization of taste disorders","volume":"164","author":"Bromley","year":"2019","journal-title":"Handb. 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