{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,20]],"date-time":"2026-08-20T16:33:46Z","timestamp":1787243626798,"version":"build-2736575974"},"reference-count":19,"publisher":"MDPI AG","issue":"3","license":[{"start":{"date-parts":[[2019,9,3]],"date-time":"2019-09-03T00:00:00Z","timestamp":1567468800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Greek State Scholarships Foundation","award":["5001552"],"award-info":[{"award-number":["5001552"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Veterinary Sciences"],"abstract":"<jats:p>Intracellular bacteria provoking zoonoses, such as those of the genus Brucella, present a host cell tropism mostly limited to the monocyte\/macrophage lineage, leading to chronic inflammatory reactions, difficult-to-eradicate-infections, and widespread prevalence among ruminants. Eradication of brucellosis has been based on programs that translate into a substantial financial burden for both the authorities and stockbreeders, if not strictly followed. To this end, we sought to create an in vitro cell model that could be utilized as future reference for adequately measuring the number of engulfed brucellae\/cell, using peripheral blood-derived sheep macrophages infected with B. melitensis at decimal multiplicities of infection (MOI = 5000-5), to simulate the host cell\/microorganism interaction and monitor bacterial loads up to 6 days post-infection. We show that the MOI = 5000 leads to high numbers of engulfed bacteria without affecting macrophages\u2019 viability and that the minimum detection limit of our Real-Time PCR assay was 3.97 \u00b1 5.58 brucellae\/cell. Moreover, we observed a time-associated, significant gradual reduction in bacterial loads from Day 2 to Day 6 post-infection (p = 0.0013), as part of the natural bactericidal properties of macrophages. Overall, the work presented here constitutes a reliable in vitro cell model of Brucella melitensis for research purposes that can be utilized to adequately measure the number of engulfed brucellae\/cell and provides insights towards future utilization of molecular biology-based methods for detection of Brucella.<\/jats:p>","DOI":"10.3390\/vetsci6030071","type":"journal-article","created":{"date-parts":[[2019,9,4]],"date-time":"2019-09-04T08:28:13Z","timestamp":1567585693000},"page":"71","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":6,"title":["A Cellular Model of Infection with Brucella melitensis in Ovine Macrophages: Novel Insights for Intracellular Bacterial Detection"],"prefix":"10.3390","volume":"6","author":[{"given":"Garyfalia","family":"Karponi","sequence":"first","affiliation":[{"name":"Department of Microbiology and Infectious Diseases, School of Veterinary Medicine, Faculty of Health Sciences, Aristotle University of Thessaloniki, 54124 Thessaloniki, Greece"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Spyridon K.","family":"Kritas","sequence":"additional","affiliation":[{"name":"Department of Microbiology and Infectious Diseases, School of Veterinary Medicine, Faculty of Health Sciences, Aristotle University of Thessaloniki, 54124 Thessaloniki, Greece"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9008-5823","authenticated-orcid":false,"given":"Eleni","family":"Papanikolaou","sequence":"additional","affiliation":[{"name":"Laboratory of Biology, School of Medicine, National and Kapodistrian University of Athens, 11527 Athens, Greece"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3532-5724","authenticated-orcid":false,"given":"Evanthia","family":"Petridou","sequence":"additional","affiliation":[{"name":"Department of Microbiology and Infectious Diseases, School of Veterinary Medicine, Faculty of Health Sciences, Aristotle University of Thessaloniki, 54124 Thessaloniki, Greece"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2019,9,3]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"53","DOI":"10.20506\/rst.32.1.2187","article-title":"Epidemiology of brucellosis in domestic animals caused by Brucella melitensis, Brucella suis and Brucella abortus","volume":"32","year":"2013","journal-title":"Rev. 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