{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,18]],"date-time":"2026-08-18T05:00:55Z","timestamp":1787029255190,"version":"build-2736575974"},"reference-count":34,"publisher":"MDPI AG","issue":"2","license":[{"start":{"date-parts":[[2026,2,10]],"date-time":"2026-02-10T00:00:00Z","timestamp":1770681600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/100007699","name":"University of Georgia","doi-asserted-by":"crossref","id":[{"id":"10.13039\/100007699","id-type":"DOI","asserted-by":"crossref"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Pathogens"],"abstract":"<jats:p>Understanding the determinants of host specificity in Dirofilaria immitis can be advanced through the use of the nonpermissive Mongolian gerbil (jird) model. We hypothesized that host immunity dictates D. immitis establishment following the third larval molt. Jirds were infected intraperitoneally with 100 Brugia malayi (permissive control) or D. immitis third-stage larvae (L3). Necropsies occurred at 1, 3, 10, and 36 days post infection (dpi) to quantify larvae via peritoneal lavage. Initial recovery at 1 dpi showed 37.4% for B. malayi but only 0.4% for D. immitis (p &lt; 0.0001). Dirofilaria immitis recovery increased to 23.6% by 3 dpi, suggesting a period of transient tissue residence during the third molt. Recovery for both species decreased by 10 dpi. Brugia malayi reached the immature adult stage (15.2%) by 36 dpi, whereas no viable D. immitis were recovered (p &lt; 0.0001). These findings suggest that D. immitis larvae encounter a robust cellular response, primarily macrophages, shortly after the third molt. Identifying the specific larval stage at which establishment fails provides critical insight into the mechanisms governing filarial host specificity.<\/jats:p>","DOI":"10.3390\/pathogens15020199","type":"journal-article","created":{"date-parts":[[2026,2,10]],"date-time":"2026-02-10T15:23:14Z","timestamp":1770736994000},"page":"199","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":1,"title":["Transient Intraperitoneal Residence of Dirofilaria immitis Larvae in the Mongolian Gerbil (Meriones unguiculatus)"],"prefix":"10.3390","volume":"15","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-1096-1510","authenticated-orcid":false,"given":"Elyssa","family":"Campbell","sequence":"first","affiliation":[{"name":"Department of Infectious Diseases, College of Veterinary Medicine, University of Georgia, Athens, GA 30602, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Michael","family":"Dzimianski","sequence":"additional","affiliation":[{"name":"Department of Infectious Diseases, College of Veterinary Medicine, University of Georgia, Athens, GA 30602, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Katelin","family":"Greenway","sequence":"additional","affiliation":[{"name":"Department of Infectious Diseases, College of Veterinary Medicine, University of Georgia, Athens, GA 30602, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Kaori","family":"Sakamoto","sequence":"additional","affiliation":[{"name":"Department of Infectious Diseases, College of Veterinary Medicine, University of Georgia, Athens, GA 30602, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6473-3743","authenticated-orcid":false,"given":"Andrew","family":"Moorhead","sequence":"additional","affiliation":[{"name":"Department of Infectious Diseases, College of Veterinary Medicine, University of Georgia, Athens, GA 30602, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,2,10]]},"reference":[{"key":"ref_1","unstructured":"Companion Animal Parasite Council (2026, January 15). Parasite Prevalence Maps. Available online: https:\/\/capcvet.org\/maps\/#\/2025\/all-year\/heartworm-canine\/dog\/united-states\/."},{"key":"ref_2","unstructured":"Companion Animal Parasite Council (2026, January 15). Heartworm. Revised 2026. Available online: https:\/\/capcvet.org\/guidelines\/heartworm\/."},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"251","DOI":"10.2307\/3275301","article-title":"Morphology of the larval stages of Dirofilaria immitis in the dog","volume":"47","author":"Orihel","year":"1961","journal-title":"J. Parasitol."},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"1127","DOI":"10.1016\/j.cvsm.2009.06.003","article-title":"Heartworm biology, treatment, and control","volume":"39","author":"Bowman","year":"2009","journal-title":"Vet. Clin. N. Am. Small Anim. Pract."},{"key":"ref_5","doi-asserted-by":"crossref","first-page":"425","DOI":"10.1890\/140368","article-title":"A world without parasites: Exploring the hidden ecology of infection","volume":"13","author":"Wood","year":"2015","journal-title":"Front. Ecol. Environ."},{"key":"ref_6","unstructured":"American Heartworm Society (2026, January 15). Canine Guidelines for the Prevention, Diagnosis, and Management of Heartworm (Dirofilaria immitis) Infection in Dogs. Revised 2024. Available online: https:\/\/www.heartwormsociety.org\/resources\/54-heartworm-guidelines\/375-canine-heartworm-guidelines."},{"key":"ref_7","doi-asserted-by":"crossref","first-page":"193","DOI":"10.1016\/S0065-308X(08)00204-2","article-title":"Chapter 4 Heartworm disease in animals and humans","volume":"66","author":"McCall","year":"2008","journal-title":"Adv. Parasitol."},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"513","DOI":"10.1186\/s13071-017-2433-9","article-title":"Examination of the \u201csusceptibility gap\u201d in the treatment of canine heartworm infection","volume":"10","author":"Bowman","year":"2017","journal-title":"Parasit. Vectors"},{"key":"ref_9","doi-asserted-by":"crossref","first-page":"969","DOI":"10.2307\/3277515","article-title":"Development of subperiodic Brugia malayi in the jird, Meriones unguiculatus, with notes on infections in other rodents","volume":"56","author":"Ash","year":"1970","journal-title":"J. Parasitol."},{"key":"ref_10","doi-asserted-by":"crossref","first-page":"1827","DOI":"10.1007\/s00436-014-3829-5","article-title":"Intraperitoneal development of the filarial nematode Brugia malayi in the Mongolian jird (Meriones unguiculatus)","volume":"113","author":"Mutafchiev","year":"2014","journal-title":"Parasitol. Res."},{"key":"ref_11","doi-asserted-by":"crossref","first-page":"573","DOI":"10.2307\/3279357","article-title":"Development of intraperitoneally inoculated Dirofilaria immitis in the laboratory Mongolian jird (Meriones unguiculates)","volume":"61","author":"Wong","year":"1975","journal-title":"J. Parasitol."},{"key":"ref_12","unstructured":"Filariasis Research Reagent Resource Center (2026, January 15). Collecting Infective Larvae of Brugia pahangi, B. malayi, Dirofilaria immitis, and Dirofilaria repens from Infected Mosquitoes. Available online: https:\/\/web.archive.org\/web\/20231203233659\/http:\/\/www.filariasiscenter.org\/protocols\/Protocols\/collecting-infective-larvae-of-brugia-pahangi-b.-malayi-dirofilaria-immitis-and-dirofilaria-repens-from-infected-mosquitoes."},{"key":"ref_13","unstructured":"Filariasis Research Reagent Resource Center (2026, January 15). Mosquito Rearing Techniques. Available online: https:\/\/web.archive.org\/web\/20231204001248\/http:\/\/www.filariasiscenter.org\/protocols\/Protocols\/mosquito-rearing-techniques."},{"key":"ref_14","unstructured":"Filariasis Research Reagent Resource Center (2026, January 15). Infecting Aedes aegypti with Brugia pahangi, B. malayi, and Dirofilaria immitis. Available online: https:\/\/web.archive.org\/web\/20231203232414\/http:\/\/www.filariasiscenter.org\/protocols\/Protocols\/infecting-aedes-aegypti-with-brugia-pahangi-b.-malayi-and-dirofilaria-immitis."},{"key":"ref_15","unstructured":"Filariasis Research Reagent Resource Center (2026, January 15). Experimental Infection of Dogs, Cats, Ferrets, and Rodents with Dirofilaria immitis, Brugia malayi, B. pahangi, or Dipetalonema reconditum. Available online: https:\/\/web.archive.org\/web\/20231204004252\/http:\/\/www.filariasiscenter.org\/protocols\/Protocols\/experimental-infection-of-dogs-cats-ferrets-and-rodents-with-dirofilaria-immitis-brugia-malayi-b.-pahangi-or-dipetalonema-reconditum."},{"key":"ref_16","doi-asserted-by":"crossref","first-page":"25","DOI":"10.1186\/s13071-020-04455-x","article-title":"A rapid, parasite-dependent cellular response to Dirofilaria immitis in the Mongolian jird (Meriones unguiculatus)","volume":"14","author":"Evans","year":"2021","journal-title":"Parasit. Vectors"},{"key":"ref_17","doi-asserted-by":"crossref","first-page":"20","DOI":"10.1016\/j.ijppaw.2022.03.012","article-title":"Detection of Dirofilaria immitis via integrated serological and molecular analyses in coyotes from Texas, United States","volume":"18","author":"Sobotyk","year":"2022","journal-title":"Int. J. Parasitol. Parasites Wildl."},{"key":"ref_18","doi-asserted-by":"crossref","first-page":"306","DOI":"10.1186\/s13071-022-05372-x","article-title":"Probe-based qPCR as an alternative to modified Knott\u2019s test when screening dogs for heartworm (Dirofilaria immitis) infection in combination with antigen detection tests","volume":"15","author":"Negron","year":"2022","journal-title":"Parasit. Vectors"},{"key":"ref_19","doi-asserted-by":"crossref","first-page":"319","DOI":"10.1186\/s13071-020-04185-0","article-title":"Development of a multiplex qPCR-based approach for the diagnosis of Dirofilaria immitis, D. repens and Acanthocheilonema reconditum","volume":"13","author":"Laidoudi","year":"2020","journal-title":"Parasit. Vectors"},{"key":"ref_20","doi-asserted-by":"crossref","first-page":"584","DOI":"10.1136\/gut.2004.058982","article-title":"Roles of virD4 and cagG genes in the cag pathogenicity island of Helicobacter pylori using a Mongolian gerbil model","volume":"54","author":"Saito","year":"2005","journal-title":"Gut"},{"key":"ref_21","doi-asserted-by":"crossref","first-page":"137","DOI":"10.1016\/j.jtherbio.2019.02.015","article-title":"Brown adipose tissue plays thermoregulatory role within the thermoneutral zone in Mongolian gerbils (Meriones unguiculatus)","volume":"81","author":"Guo","year":"2019","journal-title":"J. Therm. Biol."},{"key":"ref_22","doi-asserted-by":"crossref","unstructured":"Lewczuk, A., Boraty\u0144ska-Jasi\u0144ska, A., and Zab\u0142ocka, B. (2023). Validation of the reference genes for expression analysis in the hippocampus after transient ischemia\/reperfusion injury in gerbil brain. Int. J. Mol. Sci., 24.","DOI":"10.3390\/ijms24032756"},{"key":"ref_23","unstructured":"Bio-Rad Laboratories, Inc. (2026, January 15). QX200TM Droplet Reader and QX Manager Software, Standard Edition. Version 2.2, 2023. Available online: https:\/\/www.bio-rad.com\/en-us\/life-science\/digital-pcr\/qx-software."},{"key":"ref_24","doi-asserted-by":"crossref","first-page":"3887","DOI":"10.1128\/JCM.00969-06","article-title":"Detection of Brugia parasite DNA in human blood by real-time PCR","volume":"44","author":"Rao","year":"2006","journal-title":"J. Clin. Microbiol."},{"key":"ref_25","doi-asserted-by":"crossref","first-page":"33","DOI":"10.1016\/j.molbiopara.2013.05.001","article-title":"A TaqMan-based multiplex real-time PCR assay for the simultaneous detection of Wuchereria bancrofti and Brugia malayi","volume":"189","author":"Pilotte","year":"2013","journal-title":"Mol. Biochem. Parasitol."},{"key":"ref_26","doi-asserted-by":"crossref","first-page":"2199","DOI":"10.2460\/ajvr.1982.43.12.2199","article-title":"Developmental stages of Dirofilaria immitis in the dog","volume":"43","author":"Kotani","year":"1982","journal-title":"Am. J. Vet. Res."},{"key":"ref_27","doi-asserted-by":"crossref","first-page":"822","DOI":"10.1645\/GE-400R.1","article-title":"Profiling the cellular immune response to multiple Brugia pahangi infections in a susceptible host","volume":"91","author":"Chirgwin","year":"2005","journal-title":"J. Parasitol."},{"key":"ref_28","doi-asserted-by":"crossref","first-page":"330","DOI":"10.1016\/0014-4894(76)90100-4","article-title":"Brugia malayi, Brugia pahangi, and Brugia patei: Pulmonary pathology in jirds, Meriones unguiculatus","volume":"40","author":"Vincent","year":"1976","journal-title":"Exp. Parasitol."},{"key":"ref_29","doi-asserted-by":"crossref","first-page":"283","DOI":"10.1017\/S0022149X00008105","article-title":"Variable infectivity of third-stage larvae of Brugia malayi","volume":"59","author":"Eberhard","year":"1985","journal-title":"J. Helminthol."},{"key":"ref_30","doi-asserted-by":"crossref","first-page":"237","DOI":"10.2307\/3283753","article-title":"Early migration and development of Dirofilaria immitis in the Ferret, Mustela putorius furo","volume":"80","author":"Supakorndej","year":"1994","journal-title":"J. Parasitol."},{"key":"ref_31","unstructured":"(2026, January 15). H.R.4757. Cease Animal Research Grants Overseas Act of 2023. 118th Congress (2023\u20132024) 2023, Available online: https:\/\/www.congress.gov\/bill\/118th-congress\/house-bill\/4757."},{"key":"ref_32","unstructured":"(2026, January 15). MI-SB0149. Animals: Research Facilities; Certain Research Facilities to Offer Certain Laboratory Animals for Adoption Before Euthanization; Require. Amends Title & Secs. 1 & 7 of 1969 PA 224 (MCL 287.381 & 287.387) & Adds Sec. 8a. TIE BAR WITH: SB 0148\u201923. State of Michigan, 102nd Legislature\u2014Regular Session of 2023 2023 02\/13\/2024. Available online: https:\/\/legiscan.com\/MI\/text\/SB0149\/id\/2864838."},{"key":"ref_33","unstructured":"(2026, January 15). S.4288. Reducing Animal Testing Act. 117th Congress (2021\u20132022) 2022, Available online: https:\/\/www.congress.gov\/bill\/117th-congress\/senate-bill\/4288."},{"key":"ref_34","unstructured":"(2026, January 15). S.1378. Animal Freedom from Testing, Experiments, and Research Act of 2021. 117th Congress (2021\u20132022) 2021, Available online: https:\/\/www.congress.gov\/bill\/117th-congress\/senate-bill\/1378\/all-info."}],"container-title":["Pathogens"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/2076-0817\/15\/2\/199\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2026,2,12]],"date-time":"2026-02-12T05:14:54Z","timestamp":1770873294000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/2076-0817\/15\/2\/199"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2026,2,10]]},"references-count":34,"journal-issue":{"issue":"2","published-online":{"date-parts":[[2026,2]]}},"alternative-id":["pathogens15020199"],"URL":"https:\/\/doi.org\/10.3390\/pathogens15020199","relation":{},"ISSN":["2076-0817"],"issn-type":[{"value":"2076-0817","type":"electronic"}],"subject":[],"published":{"date-parts":[[2026,2,10]]}}}