{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,6]],"date-time":"2026-10-06T23:59:40Z","timestamp":1791331180966,"version":"4.3.1"},"reference-count":56,"publisher":"Frontiers Media SA","license":[{"start":{"date-parts":[[2022,8,25]],"date-time":"2022-08-25T00:00:00Z","timestamp":1661385600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":["frontiersin.org"],"crossmark-restriction":true},"short-container-title":["Front. Cell. Infect. Microbiol."],"abstract":"<jats:p>Enolase, a multifunctional protein expressed by multiple pathogens activates plasminogen to promote proteolysis on components of the extracellular matrix, an important event in early host-pathogen interactions. A secreted form of enolase that is released upon the interaction of trophozoites with epithelial cells has been detected in the secretome of <jats:italic>G. duodenalis<\/jats:italic>. However, the role of enolase in the host-pathogen interactions remains largely unknown. In this work, the effects of <jats:italic>G. duodenalis<\/jats:italic> enolase (Gd-eno) on the epithelial cell model (IEC-6) were analyzed. Firstly, the coding sequence of <jats:italic>Giardia<\/jats:italic> enolase was cloned and the recombinant protein used to raise antibodies that were then used to define the localization and role of enolase in epithelial cell-trophozoite interactions. Gd-eno was detected in small cytoplasmic vesicles as well as at the surface and is enriched in the region of the ventral disk of <jats:italic>Giardia<\/jats:italic> trophozoites. Moreover, the blocking of the soluble monomeric form of the enzyme, which is secreted upon interaction with IEC-6 cells by the anti-rGd-eno antibodies, significantly inhibited trophozoite attachment to intestinal IEC-6 cell monolayers. Further, rGd-eno was able to bind human plasminogen (HsPlg) and enhanced plasmin activity <jats:italic>in vitro<\/jats:italic> when the trophozoites were incubated with the intrinsic plasminogen activators of epithelial cells. In IEC-6 cells, rGd-eno treatment induced a profuse cell damage characterized by copious vacuolization, intercellular separation and detachment from the substrate; this effect was inhibited by either anti-Gd-eno Abs or the plasmin inhibitor \u03f5- aminocaproic acid. Lastly, we established that in epithelial cells rGd-eno treatment induced a necroptotic-like process mediated by tumor necrosis factor \u03b1 (TNF-\u03b1) and the apoptosis inducing factor (AIF), but independent of caspase-3. All together, these results suggest that <jats:italic>Giardia<\/jats:italic> enolase is a secreted moonlighting protein that stimulates a necroptotic-like process in IEC-6 epithelial cells <jats:italic>via<\/jats:italic> plasminogen activation along to TNF\u03b1 and AIF activities and must be considered as a virulence factor.<\/jats:p>","DOI":"10.3389\/fcimb.2022.928687","type":"journal-article","created":{"date-parts":[[2022,8,25]],"date-time":"2022-08-25T07:49:19Z","timestamp":1661413759000},"update-policy":"https:\/\/doi.org\/10.3389\/crossmark-policy","source":"Crossref","is-referenced-by-count":9,"title":["Giardia duodenalis enolase is secreted as monomer during trophozoite-epithelial cell interactions, activates plasminogen and induces necroptotic damage"],"prefix":"10.3389","volume":"12","author":[{"given":"Elisa","family":"Barroeta-Echegaray","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Roc\u00edo","family":"Fonseca-Li\u00f1\u00e1n","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ra\u00fal","family":"Arg\u00fcello-Garc\u00eda","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Rafael","family":"Rodr\u00edguez-Mu\u00f1oz","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Rosa Mar\u00eda","family":"Berm\u00fadez-Cruz","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Porfirio","family":"Nava","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"M. 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