{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,13]],"date-time":"2026-04-13T06:44:08Z","timestamp":1776062648549,"version":"3.50.1"},"reference-count":38,"publisher":"Frontiers Media SA","license":[{"start":{"date-parts":[[2026,4,13]],"date-time":"2026-04-13T00:00:00Z","timestamp":1776038400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100007414","name":"Qassim University","doi-asserted-by":"publisher","id":[{"id":"10.13039\/501100007414","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":["frontiersin.org"],"crossmark-restriction":true},"short-container-title":["Front. Pharmacol."],"abstract":"<jats:sec>\n                    <jats:title>Background<\/jats:title>\n                    <jats:p>\n                      <jats:italic>Clostridioides difficile<\/jats:italic>\n                      infection (CDI) is a significant global health burden.\n                      <jats:italic>Galleria mellonella<\/jats:italic>\n                      offers an ethical, cost-effective invertebrate alternative to mammalian pre-clinical models. This study evaluated the feasibility of using\n                      <jats:italic>Galleria mellonella<\/jats:italic>\n                      to study CDI pathogenesis and treatment.\n                    <\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Methods<\/jats:title>\n                    <jats:p>\n                      We optimized larval storage, temperature, and inoculum size. The model was validated by assessing survival following infection with diverse\n                      <jats:italic>C. difficile<\/jats:italic>\n                      ribotypes (RT) and vancomycin treatment. Bacterial burden was quantified via qPCR, and survival was analyzed using Kaplan-Meier curves.\n                    <\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Results<\/jats:title>\n                    <jats:p>\n                      An inoculum of 1 \u00d7 10\n                      <jats:sup>7<\/jats:sup>\n                      \u00a0CFU\/mL in fresh larvae (&amp;lt;7 days since receipt) at 37\u00a0\u00b0C proved optimal. Fresh larvae exhibited significantly higher survival compared to older larvae (P = 0.003). Infection with toxigenic strains resulted in significantly lower survival (35%) compared to uninfected controls (90%; P &amp;lt; 0.001), with virulence varying significantly among RTs. Vancomycin treatment improved survival to 90% in a dose-dependent manner compared to untreated controls (P &amp;lt; 0.001), with a corresponding reduction in bacterial burden confirmed by qPCR.\n                    <\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Conclusion<\/jats:title>\n                    <jats:p>\n                      We conclude that this optimized oral\n                      <jats:italic>G. mellonella<\/jats:italic>\n                      model provides a robust and ethically sound high-throughput platform for screening novel anti-\n                      <jats:italic>C. difficile<\/jats:italic>\n                      compounds and for comparative virulence studies of diverse ribotypes, effectively bridging\n                      <jats:italic>in vitro<\/jats:italic>\n                      assays and mammalian studies for future drug development.\n                    <\/jats:p>\n                  <\/jats:sec>","DOI":"10.3389\/fphar.2026.1792859","type":"journal-article","created":{"date-parts":[[2026,4,13]],"date-time":"2026-04-13T05:45:34Z","timestamp":1776059134000},"update-policy":"https:\/\/doi.org\/10.3389\/crossmark-policy","source":"Crossref","is-referenced-by-count":0,"title":["Bridging the gap in AMR research: validation of a standardized Galleria mellonella model to evaluate Clostridioides difficile pathogenesis and treatment efficacy"],"prefix":"10.3389","volume":"17","author":[{"given":"Faris S.","family":"Alnezary","sequence":"first","affiliation":[{"name":"Department of Pharmacy Practice, College of Pharmacy, Taibah University","place":["Madinah, Saudi Arabia"]}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Masaad Saeed","family":"Almutairi","sequence":"additional","affiliation":[{"name":"Department of Pharmacy Practice, College of Pharmacy, Qassim University","place":["Qassim, Saudi Arabia"]}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1965","published-online":{"date-parts":[[2026,4,13]]},"reference":[{"key":"B1","doi-asserted-by":"publisher","first-page":"1","DOI":"10.1016\/j.micpath.2018.04.013","article-title":"Molecular characterization of Clostridium difficile isolated from carriage and association of its pathogenicity to prevalent toxic genes","volume":"120","author":"Abuderman","year":"2018","journal-title":"Microb. 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