{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,30]],"date-time":"2026-04-30T03:21:00Z","timestamp":1777519260466,"version":"3.51.4"},"reference-count":30,"publisher":"MDPI AG","issue":"18","license":[{"start":{"date-parts":[[2024,9,13]],"date-time":"2024-09-13T00:00:00Z","timestamp":1726185600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100004586","name":"FAPERJ","doi-asserted-by":"publisher","award":["E-26\/210.879\/2024"],"award-info":[{"award-number":["E-26\/210.879\/2024"]}],"id":[{"id":"10.13039\/501100004586","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100004586","name":"FAPERJ","doi-asserted-by":"publisher","award":["E26\/211.574\/2019"],"award-info":[{"award-number":["E26\/211.574\/2019"]}],"id":[{"id":"10.13039\/501100004586","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Cells"],"abstract":"<jats:p>Giardia doudenalis (lamblia, intestinalis) is a protozoan parasite that inhabits the lumen of the upper small intestine of vertebrates, causing chronic abdominal pains and severe diarrhea, symptoms of giardiasis, a persistent and recurrent infection. This characteristic is mainly due to the presence of membrane variant-specific surface proteins (VSPs) that give this parasite the ability to successively infect the host through antigenic variation. Using high-resolution scanning microscopy (HR-SM), we observed the presence, formation, and extension of tunneling-nanotube-like surface structures in Giardia, especially following parasite challenges with VSP antibodies. They were seen all over the parasite surface, both in vitro and in vivo, showing that G. duodenalis nanotube formation occurs in complex environments such as the gut. In addition, we also observed that some of these nanotubes displayed a periodic strangulation that produces 100 nm vesicles that seemed to be released in a process similar to that previously observed in Trypanosoma brucei. The presence of nanotube-like structures in G. duodenalis highlights yet another strategy of cellular communication utilized by these parasites, whether between themselves or with the host cell.<\/jats:p>","DOI":"10.3390\/cells13181538","type":"journal-article","created":{"date-parts":[[2024,9,13]],"date-time":"2024-09-13T06:39:16Z","timestamp":1726209556000},"page":"1538","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":4,"title":["Tunneling Nanotube-like Structures in Giardia duodenalis"],"prefix":"10.3390","volume":"13","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-9294-6597","authenticated-orcid":false,"given":"Victor","family":"Midlej","sequence":"first","affiliation":[{"name":"Structural Biology Laboratory, Oswaldo Cruz Institution, Fiocruz, Rio de Janeiro 21040-900, Brazil"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0354-5538","authenticated-orcid":false,"given":"Albano H.","family":"Tenaglia","sequence":"additional","affiliation":[{"name":"Consejo Nacional de Investigaciones Cient\u00edficas y T\u00e9cnicas (CONICET), Centro de Investigaciones en Qu\u00edmica Biol\u00f3gica de C\u00f3rdoba (CIQUIBIC), Universidad Nacional de C\u00f3rdoba, C\u00f3rdoba 5000, Argentina"},{"name":"Departamento de Qu\u00edmica Biol\u00f3gica Ranwel Caputto, Facultad de Ciencias Qu\u00edmicas, Universidad Nacional de C\u00f3rdoba, C\u00f3rdoba 5000, Argentina"},{"name":"Facultad de Ciencias de la Salud, Universidad Cat\u00f3lica de C\u00f3rdoba (UCC), C\u00f3rdoba 5004, Argentina"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3797-8315","authenticated-orcid":false,"given":"Hugo D.","family":"Luj\u00e1n","sequence":"additional","affiliation":[{"name":"Institute of Medical Microbiology and Hygiene, University Medical Center of the Johannes Gutenberg-University Mainz, 55131 Mainz, Germany"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1895-1299","authenticated-orcid":false,"given":"Wanderley","family":"de Souza","sequence":"additional","affiliation":[{"name":"Laborat\u00f3rio de Ultraestrutura Celular Hertha Meyer, Centro de Pesquisa em Medicina de Precis\u00e3o, Instituto de Biof\u00edsica Carlos Chagas Filho, Universidade Federal do Rio de Janeiro, Rio de Janeiro 21941-902, Brazil"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2024,9,13]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"526","DOI":"10.1016\/j.tcb.2016.03.003","article-title":"Signaling by Cellular Protrusions: Keeping the Conversation Private","volume":"26","author":"Buszczak","year":"2016","journal-title":"Trends Cell Biol."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"414","DOI":"10.1016\/j.tcb.2008.07.003","article-title":"Cytonemes and tunneling nanotubules in cell-cell communication and viral pathogenesis","volume":"18","author":"Sherer","year":"2008","journal-title":"Trends Cell Biol."},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"144","DOI":"10.1111\/boc.201400063","article-title":"Inhibition of the GTPase dynamin or actin depolymerization initiates outward plasma membrane tubulation\/vesiculation (cytoneme formation) in neutrophils","volume":"107","author":"Galkina","year":"2015","journal-title":"Biol. 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