{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,12]],"date-time":"2026-10-12T13:44:54Z","timestamp":1791812694928,"version":"4.3.4"},"reference-count":28,"publisher":"Oxford University Press (OUP)","license":[{"start":{"date-parts":[[2026,10,5]],"date-time":"2026-10-05T00:00:00Z","timestamp":1791158400000},"content-version":"vor","delay-in-days":277,"URL":"https:\/\/creativecommons.org\/licenses\/by-nc-nd\/4.0\/"}],"funder":[{"DOI":"10.13039\/100000199","name":"United States Department of Agriculture","doi-asserted-by":"publisher","award":["58-3022-1-018-F"],"award-info":[{"award-number":["58-3022-1-018-F"]}],"id":[{"id":"10.13039\/100000199","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100002924","name":"FEDER","doi-asserted-by":"publisher","id":[{"id":"10.13039\/501100002924","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":[],"published-print":{"date-parts":[[2026,1,7]]},"abstract":"<jats:title>Abstract<\/jats:title>\n                  <jats:p>Ehrlichia ruminantium, the causative agent of heartwater disease, is an obligate intracellular bacterium that poses significant economic threats to livestock production in endemic regions. Current research models present substantial ethical, logistical, and economic constraints, particularly for studying host\u2013pathogen interactions within arthropod vectors. Here, we establish Galleria mellonella larvae as a tractable invertebrate infection model for Ehrlichia ruminantium, enabling experimental investigation of pathogen persistence and host\u2013pathogen interactions in an arthropod system. Following infection, G. mellonella proved susceptible to E. ruminantium with moderate mortality and remarkable bacterial persistence. Using rhodamine-labeled bacteria and fluorescence microscopy, we tracked bacterial dissemination from injection sites to systemic distribution in characteristic segmental patterns throughout the larval body. Rhodamine-labeled bacteria were consistently associated with hemocytes, the primary immune cells of G. mellonella, although widefield imaging cannot establish intracellular localization. Quantitative PCR revealed stable bacterial loads over the study period, and bacteria recovered from infected larvae remained viable and infectious for endothelial cells. These findings show that E. ruminantium persists in G. mellonella for at least two weeks without inducing a detectable melanization response. The fluorescence adopted a reproducible segmental distribution whose biological basis remains to be determined. This model offers significant advantages: ethical acceptability, cost-effectiveness, experimental tractability, and compatibility with high-throughput screening approaches. The G. mellonella system represents a valuable complement to existing mammalian models and provides a unique platform for investigating arthropod-specific aspects of E. ruminantium biology, screening antimicrobial compounds, and testing hypotheses of immune evasion that may inform strategies for heartwater disease control.<\/jats:p>","DOI":"10.1093\/femsle\/fnag113","type":"journal-article","created":{"date-parts":[[2026,10,2]],"date-time":"2026-10-02T11:40:32Z","timestamp":1790941232000},"source":"Crossref","is-referenced-by-count":0,"title":["<i>Galleria mellonella<\/i>\n                    as a novel invertebrate model for studying\n                    <i>Ehrlichia ruminantium<\/i>\n                    pathogenesis and host\u2013pathogen interactions"],"prefix":"10.1093","volume":"373","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-6597-9940","authenticated-orcid":false,"given":"Ma\u00eblle","family":"Bayet","sequence":"first","affiliation":[{"name":"CIRAD, UMR ASTRE, Centre for Research and Surveillance on Vector-borne Diseases in the Caribbean, WOAH Reference Laboratory for Heartwater , F-97170 Petit-Bourg, Guadeloupe ,","place":["France"]},{"name":"ASTRE, CIRAD, INRAE, Universit\u00e9 Montpellier , 34000 Montpellier ,","place":["France"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9335-446X","authenticated-orcid":false,"given":"Christina","family":"Nielsen-Leroux","sequence":"additional","affiliation":[{"name":"INRAE, Micalis & AgroParisTech-Universit\u00e9 Paris Saclay , 78352 Jouy-en-Josas ,","place":["France"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8390-4931","authenticated-orcid":false,"given":"Val\u00e9rie","family":"Rodrigues","sequence":"additional","affiliation":[{"name":"CIRAD, UMR ASTRE, Centre for Research and Surveillance on Vector-borne Diseases in the Caribbean, WOAH Reference Laboratory for Heartwater , F-97170 Petit-Bourg, Guadeloupe ,","place":["France"]},{"name":"ASTRE, CIRAD, INRAE, Universit\u00e9 Montpellier , 34000 Montpellier ,","place":["France"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2735-176X","authenticated-orcid":false,"given":"Damien F","family":"Meyer","sequence":"additional","affiliation":[{"name":"CIRAD, UMR ASTRE, Centre for Research and Surveillance on Vector-borne Diseases in the Caribbean, WOAH Reference Laboratory for Heartwater , F-97170 Petit-Bourg, Guadeloupe ,","place":["France"]},{"name":"ASTRE, CIRAD, INRAE, Universit\u00e9 Montpellier , 34000 Montpellier ,","place":["France"]}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"286","published-online":{"date-parts":[[2026,10,5]]},"reference":[{"key":"2026101208461924000_bib1","doi-asserted-by":"publisher","first-page":"66","DOI":"10.1159\/000535986","article-title":"Ehrlichia chaffeensis co-opts phagocytic hemocytes for systemic dissemination in the lone star tick, Amblyomma americanum","volume":"16","author":"Adegoke","year":"2024","journal-title":"J Innate Immun"},{"key":"2026101208461924000_bib2","doi-asserted-by":"publisher","first-page":"557","DOI":"10.20506\/rst.34.2.2379","article-title":"Heartwater-Ehrlichia ruminantium infection","volume":"34","author":"Allsopp","year":"2015","journal-title":"Rev Sci Tech OIE"},{"key":"2026101208461924000_bib3","doi-asserted-by":"publisher","first-page":"fuad011","DOI":"10.1093\/femsre\/fuad011","article-title":"Galleria mellonella-intracellular bacteria pathogen infection models: the ins and outs","volume":"47","author":"Asai","year":"2023","journal-title":"FEMS Microbiol Rev"},{"key":"2026101208461924000_bib4","doi-asserted-by":"publisher","first-page":"e631","DOI":"10.1371\/journal.pone.0000631","article-title":"Brucella abortus uses a stealthy strategy to avoid activation of the innate immune system during the onset of infection","volume":"2","author":"Barquero-Calvo","year":"2007","journal-title":"PLoS One"},{"key":"2026101208461924000_bib5","doi-asserted-by":"publisher","first-page":"63","DOI":"10.1016\/S0304-4017(02)00421-1","article-title":"Preparation of Ehrlichia ruminantium challenge material for quantifiable and reproducible challenge in mice and sheep","volume":"112","author":"Brayton","year":"2003","journal-title":"Vet Parasitol"},{"key":"2026101208461924000_bib6","doi-asserted-by":"publisher","first-page":"545","DOI":"10.1084\/jem.20030088","article-title":"Brucella evades macrophage killing via VirB-dependent sustained interactions with the endoplasmic reticulum","volume":"198","author":"Celli","year":"2003","journal-title":"J Exp Med"},{"key":"2026101208461924000_bib7","doi-asserted-by":"publisher","first-page":"263","DOI":"10.1016\/j.it.2008.02.009","article-title":"The proPO-system: pros and cons for its role in invertebrate immunity","volume":"29","author":"Cerenius","year":"2008","journal-title":"Trends Immunol"},{"key":"2026101208461924000_bib8","doi-asserted-by":"publisher","first-page":"106857","DOI":"10.1016\/j.prevetmed.2026.106857","article-title":"Risk factors associated with Ehrlichia ruminantium and tick infestation amongst cattle in Guadeloupe, French West Indies","volume":"252","author":"Dufleit","year":"2026","journal-title":"Prevent Vet Med"},{"key":"2026101208461924000_bib9","doi-asserted-by":"publisher","first-page":"105930","DOI":"10.1016\/j.micpath.2022.105930","article-title":"Development and evaluation of the Galleria mellonella (greater wax moth) infection model to study Brucella host-pathogen interaction","volume":"174","author":"Elizalde-Bielsa","year":"2023","journal-title":"Microb Pathogen"},{"key":"2026101208461924000_bib10","first-page":"50964","article-title":"Use of Galleria mellonella as a model organism to study Legionella pneumophila infection","author":"Harding","year":"2013","journal-title":"J Vis Exp"},{"key":"2026101208461924000_bib11","doi-asserted-by":"publisher","first-page":"2780","DOI":"10.1128\/IAI.00510-12","article-title":"Legionella pneumophila pathogenesis in the Galleria mellonella infection model","volume":"80","author":"Harding","year":"2012","journal-title":"Infect Immun"},{"key":"2026101208461924000_bib12","doi-asserted-by":"publisher","first-page":"101","DOI":"10.1016\/j.femsre.2003.09.002","article-title":"Exploiting the potential of insects for in vivo pathogenicity testing of microbial pathogens","volume":"28","author":"Kavanagh","year":"2004","journal-title":"FEMS Microbiol Rev"},{"key":"2026101208461924000_bib13","doi-asserted-by":"publisher","first-page":"55","DOI":"10.1186\/1741-7007-11-55","article-title":"Spatial and temporal in vivo analysis of circulating and sessile immune cells in mosquitoes: hemocyte mitosis following infection","volume":"11","author":"King","year":"2013","journal-title":"BMC Biol"},{"key":"2026101208461924000_bib14","doi-asserted-by":"publisher","first-page":"e06166","DOI":"10.7554\/eLife.06166","article-title":"Drosophila sessile hemocyte clusters are true hematopoietic tissues that regulate larval blood cell differentiation","volume":"4","author":"Leit\u00e3o","year":"2015","journal-title":"eLife"},{"key":"2026101208461924000_bib15","doi-asserted-by":"publisher","first-page":"241","DOI":"10.1007\/978-3-319-46859-4","article-title":"Ehrlichia ruminantium: the causal agent of heartwater","volume-title":"Rickettsiales","author":"Marcelino","year":"2016"},{"key":"2026101208461924000_bib16","doi-asserted-by":"publisher","first-page":"e3","DOI":"10.1017\/S1462399410001730","article-title":"Molecular and cellular pathobiology of Ehrlichia infection: targets for new therapeutics and immunomodulation strategies","volume":"13","author":"McBride","year":"2011","journal-title":"Expert Rev Mol Med"},{"key":"2026101208461924000_bib17","doi-asserted-by":"crossref","first-page":"782733","DOI":"10.3389\/fcimb.2021.782733","article-title":"Galleria mellonella as a suitable model of bacterial infection: past, present and future","volume":"11","author":"M\u00e9nard","year":"2021","journal-title":"Front Cell Infect Microbiol"},{"key":"2026101208461924000_bib18","doi-asserted-by":"publisher","first-page":"001415","DOI":"10.1099\/mic.0.001415","article-title":"Microbe Profile: ehrlichia ruminantium\u2014stealthy as it goes","volume":"169","author":"Meyer","year":"2023","journal-title":"Microbiology"},{"key":"2026101208461924000_bib19","doi-asserted-by":"crossref","first-page":"172","DOI":"10.1016\/j.micinf.2015.11.001","article-title":"Ehrlichia\u2019s molecular tricks to manipulate their host cells","volume":"18","author":"Moum\u00e8ne","year":"2016","journal-title":"Microbes Infect"},{"key":"2026101208461924000_bib20","doi-asserted-by":"publisher","first-page":"1175","DOI":"10.1099\/mic.0.077230-0","article-title":"Galleria mellonella as an alternative model of Coxiella burnetii infection","volume":"160","author":"Norville","year":"2014","journal-title":"Microbiology"},{"key":"2026101208461924000_bib21","doi-asserted-by":"publisher","first-page":"417","DOI":"10.1016\/j.jinsphys.2006.01.005","article-title":"Insect hemocytes: what type of cell is that?","volume":"52","author":"Ribeiro","year":"2006","journal-title":"J Insect Physiol"},{"key":"2026101208461924000_bib22","doi-asserted-by":"publisher","first-page":"297","DOI":"10.1007\/978-3-319-75241-9","article-title":"Role and function of the Type IV secretion system in Anaplasma and Ehrlichia species","volume-title":"Type IV Secretion in Gram-Negative and Gram-Positive Bacteria","author":"Rikihisa","year":"2017"},{"key":"2026101208461924000_bib23","article-title":"Heartwater","volume-title":"MSD Manual, Veterinary Manual","author":"Rodrigues","year":"2024"},{"key":"2026101208461924000_bib24","doi-asserted-by":"publisher","first-page":"100959","DOI":"10.1016\/j.ijppaw.2024.100959","article-title":"Retrospective analysis of laboratory diagnostic data to assess the prevalence and seasonal variation of Ehrlichia ruminantium in commercial farms of Lephalale Municipality, Limpopo, South Africa","volume":"24","author":"Seakamela","year":"2024","journal-title":"Int J Parasitol Parasit Wildlife"},{"key":"2026101208461924000_bib25","doi-asserted-by":"publisher","first-page":"424","DOI":"10.1196\/annals.1374.131","article-title":"Evaluation of E. ruminantium genes in DBA\/2 mice as potential DNA vaccine candidates for control of heartwater","volume":"1078","author":"Simbi","year":"2006","journal-title":"Ann New York Acad Sci"},{"key":"2026101208461924000_bib26","doi-asserted-by":"crossref","DOI":"10.1007\/978-3-319-46859-4","volume-title":"Rickettsiales: Biology, Molecular Biology, Epidemiology, and Vaccine Development","author":"Thomas","year":"2016"},{"key":"2026101208461924000_bib27","doi-asserted-by":"crossref","first-page":"67","DOI":"10.3390\/nano15010067","article-title":"Galleria mellonella (Greater Wax Moth) as a reliable animal model to study the efficacy of nanomaterials in fighting pathogens","volume":"15","author":"Villani","year":"2025","journal-title":"Nanomaterials"},{"key":"2026101208461924000_bib28","author":"World Organisation for Animal Health (WOAH)","year":"2018"}],"container-title":["FEMS Microbiology Letters"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/academic.oup.com\/femsle\/advance-article-pdf\/doi\/10.1093\/femsle\/fnag113\/71604093\/fnag113.pdf","content-type":"application\/pdf","content-version":"am","intended-application":"syndication"},{"URL":"https:\/\/academic.oup.com\/femsle\/article-pdf\/doi\/10.1093\/femsle\/fnag113\/71604093\/fnag113.pdf","content-type":"application\/pdf","content-version":"vor","intended-application":"syndication"},{"URL":"https:\/\/academic.oup.com\/femsle\/article-pdf\/doi\/10.1093\/femsle\/fnag113\/71604093\/fnag113.pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2026,10,12]],"date-time":"2026-10-12T12:46:38Z","timestamp":1791809198000},"score":1,"resource":{"primary":{"URL":"https:\/\/academic.oup.com\/femsle\/article\/doi\/10.1093\/femsle\/fnag113\/8864985"}},"subtitle":[],"editor":[{"given":"Akio","family":"Nakane","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"editor"}]}],"short-title":[],"issued":{"date-parts":[[2026]]},"references-count":28,"URL":"https:\/\/doi.org\/10.1093\/femsle\/fnag113","relation":{},"ISSN":["1574-6968"],"issn-type":[{"value":"1574-6968","type":"electronic"}],"subject":[],"published-other":{"date-parts":[[2026]]},"published":{"date-parts":[[2026]]},"article-number":"fnag113"}}