{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,29]],"date-time":"2026-09-29T08:40:36Z","timestamp":1790671236966,"version":"4.1.0"},"reference-count":44,"publisher":"MDPI AG","issue":"9","license":[{"start":{"date-parts":[[2021,8,29]],"date-time":"2021-08-29T00:00:00Z","timestamp":1630195200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Pathogens"],"abstract":"<jats:p>Chlamydia (C.) suis can often be isolated from conjunctival swab specimens from pigs with conjunctivitis or keratoconjunctivitis. In the field, it is assumed to be a multifactorial disease triggered by immunosuppressing factors. This is the first experimental study to provoke clinical signs of conjunctivitis in pigs after C. suis primary mono-infection. Five six-week-old male piglets, free of ocular chlamydia shedding and seronegative for Chlamydia, were conjunctivally infected with the C. suis-type strain S45 (1 \u00d7 109 inclusion forming units), while four piglets served as negative controls. The infection group developed clinical signs of conjunctivitis with a peak in the first week post-infection. Immunohistochemical evaluation revealed the presence of Chlamydia not only in the conjunctival epithelium, but also in the enlarged lacrimal glands, lungs, and intestine. No circulating antibodies could be detected during the whole study period of three weeks, although three different test systems were applied as follows: the complement fixation test, MOMP-based Chlamydiaceae ELISA, and PmpC-based C. suis ELISA. Meanwhile, high numbers of IFN-\u03b3-producing lymphocytes within PBMC were seen after C. suis re-stimulation 14 days post-infection. Hence, these data suggest that entry via the eye may not elicit immunological responses comparable to other routes of chlamydial infections.<\/jats:p>","DOI":"10.3390\/pathogens10091103","type":"journal-article","created":{"date-parts":[[2021,8,31]],"date-time":"2021-08-31T04:07:28Z","timestamp":1630382848000},"page":"1103","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":12,"title":["Characteristics of Chlamydia suis Ocular Infection in Pigs"],"prefix":"10.3390","volume":"10","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-4965-2088","authenticated-orcid":false,"given":"Christine","family":"Unterweger","sequence":"first","affiliation":[{"name":"University Clinic for Swine, Department for Farm Animals and Veterinary Public Health, University of Veterinary Medicine, 1210 Vienna, Austria"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7854-3812","authenticated-orcid":false,"given":"Aleksandra","family":"Inic-Kanada","sequence":"additional","affiliation":[{"name":"Institute of Specific Prophylaxis and Tropical Medicine, Center for Pathophysiology, Infectiology and Immunology, Medical University of Vienna, 1090 Vienna, Austria"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Sara","family":"Setudeh","sequence":"additional","affiliation":[{"name":"University Clinic for Swine, Department for Farm Animals and Veterinary Public Health, University of Veterinary Medicine, 1210 Vienna, Austria"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Christian","family":"Knecht","sequence":"additional","affiliation":[{"name":"University Clinic for Swine, Department for Farm Animals and Veterinary Public Health, University of Veterinary Medicine, 1210 Vienna, Austria"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Sophie","family":"Duerlinger","sequence":"additional","affiliation":[{"name":"University Clinic for Swine, Department for Farm Animals and Veterinary Public Health, University of Veterinary Medicine, 1210 Vienna, Austria"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7996-179X","authenticated-orcid":false,"given":"Melissa","family":"Stas","sequence":"additional","affiliation":[{"name":"University Clinic for Swine, Department for Farm Animals and Veterinary Public Health, University of Veterinary Medicine, 1210 Vienna, Austria"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Daisy","family":"Vanrompay","sequence":"additional","affiliation":[{"name":"Laboratory for Immunology and Animal Biotechnology, Department of Animal Science and Aquatic Ecology, Faculty of Bioscience Engineering, Coupure Links, 654, 9000 Ghent, Belgium"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Celien","family":"Kiekens","sequence":"additional","affiliation":[{"name":"Laboratory for Immunology and Animal Biotechnology, Department of Animal Science and Aquatic Ecology, Faculty of Bioscience Engineering, Coupure Links, 654, 9000 Ghent, Belgium"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Romana","family":"Steinparzer","sequence":"additional","affiliation":[{"name":"Institute for Veterinary Disease Control, Austrian Agency for Health and Food Safety (AGES), Robert Koch Gasse 17, 2340 Moedling, Austria"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2431-5889","authenticated-orcid":false,"given":"Wilhelm","family":"Gerner","sequence":"additional","affiliation":[{"name":"Institute of Immunology, Department of Pathobiology, University of Veterinary Medicine, 1210 Vienna, Austria"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Andrea","family":"Ladinig","sequence":"additional","affiliation":[{"name":"University Clinic for Swine, Department for Farm Animals and Veterinary Public Health, University of Veterinary Medicine, 1210 Vienna, Austria"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Talin","family":"Barisani-Asenbauer","sequence":"additional","affiliation":[{"name":"OCUVAC Centre of Ocular Inflammation and Infection, Laura Bassi Centre of Expertise, Center of Pathophysiology, Infectiology and Immunology, Medical University of Vienna, 1090 Vienna, Austria"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2021,8,29]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"29","DOI":"10.1186\/1297-9716-42-29","article-title":"Chlamydiaceae infections in pig","volume":"42","author":"Schautteet","year":"2011","journal-title":"Vet. 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