{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,1]],"date-time":"2026-09-01T06:47:28Z","timestamp":1788245248823,"version":"build-2803163510"},"reference-count":53,"publisher":"MDPI AG","issue":"1","license":[{"start":{"date-parts":[[2024,1,3]],"date-time":"2024-01-03T00:00:00Z","timestamp":1704240000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100003141","name":"CONAHCyT","doi-asserted-by":"publisher","award":["237523"],"award-info":[{"award-number":["237523"]}],"id":[{"id":"10.13039\/501100003141","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Pathogens"],"abstract":"<jats:p>Naegleria fowleri is a ubiquitous free-living amoeba that causes primary amoebic meningoencephalitis. As a part of the innate immune response at the mucosal level, the proteins lactoferrin (Lf) and lysozyme (Lz) are secreted and eliminate various microorganisms. We demonstrate that N. fowleri survives the individual and combined effects of bovine milk Lf (bLf) and chicken egg Lz (cLz). Moreover, amoebic proliferation was not altered, even at 24 h of co-incubation with each protein. Trophozoites\u2019 ultrastructure was evaluated using transmission electron microscopy, and these proteins did not significantly alter their organelles and cytoplasmic membranes. Protease analysis using gelatin-zymograms showed that secreted proteases of N. fowleri were differentially modulated by bLf and cLz at 3, 6, 12, and 24 h. The bLf and cLz combination resulted in the inhibition of N. fowleri-secreted proteases. Additionally, the use of protease inhibitors on bLf-zymograms demonstrated that secreted cysteine proteases participate in the degradation of bLf. Nevertheless, the co-incubation of trophozoites with bLf and\/or cLz reduced the cytopathic effect on the MDCK cell line. Our study suggests that bLf and cLz, alone or together, inhibited secreted proteases and reduced the cytopathic effect produced by N. fowleri; however, they do not affect the viability and proliferation of the trophozoites.<\/jats:p>","DOI":"10.3390\/pathogens13010044","type":"journal-article","created":{"date-parts":[[2024,1,3]],"date-time":"2024-01-03T03:18:07Z","timestamp":1704251887000},"page":"44","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":6,"title":["Lactoferrin and Lysozyme Inhibit the Proteolytic Activity and Cytopathic Effect of Naegleria fowleri Enzymes"],"prefix":"10.3390","volume":"13","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-9569-0064","authenticated-orcid":false,"given":"Moises","family":"Martinez-Castillo","sequence":"first","affiliation":[{"name":"Liver, Pancreas and Motility Laboratory, Unit of Research in Experimental Medicine, School of Medicine, Autonomous National University of Mexico (UNAM), Mexico City 06720, Mexico"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2546-2792","authenticated-orcid":false,"given":"Gerardo","family":"Ram\u00edrez-Rico","sequence":"additional","affiliation":[{"name":"Department of Cell Biology, Center for Research and Advanced Studies, Mexico City 07360, Mexico"},{"name":"Faculty of Professional Studies Cuautitlan, Autonomous National University of Mexico, Mexico City 54714, Mexico"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Mineko","family":"Shibayama","sequence":"additional","affiliation":[{"name":"Department of Infectomics and Molecular Pathogenesis, Center for Research and Advanced Studies, Mexico City 07360, Mexico"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Mireya","family":"de la Garza","sequence":"additional","affiliation":[{"name":"Department of Cell Biology, Center for Research and Advanced Studies, Mexico City 07360, Mexico"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2725-5743","authenticated-orcid":false,"given":"Jes\u00fas","family":"Serrano-Luna","sequence":"additional","affiliation":[{"name":"Department of Cell Biology, Center for Research and Advanced Studies, Mexico City 07360, Mexico"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2024,1,3]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"885","DOI":"10.1099\/jmm.0.000303","article-title":"Naegleria fowleri after 50 years: Is it a neglected pathogen?","volume":"65","author":"Debnath","year":"2016","journal-title":"J. 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