{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,14]],"date-time":"2026-07-14T10:47:03Z","timestamp":1784026023543,"version":"3.55.0"},"reference-count":35,"publisher":"MDPI AG","issue":"8","license":[{"start":{"date-parts":[[2020,8,3]],"date-time":"2020-08-03T00:00:00Z","timestamp":1596412800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100004569","name":"Ministerstwo Nauki i Szkolnictwa Wy\u017cszego","doi-asserted-by":"publisher","award":["010\/RID\/2018\/19"],"award-info":[{"award-number":["010\/RID\/2018\/19"]}],"id":[{"id":"10.13039\/501100004569","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Pathogens"],"abstract":"<jats:p>The pathology of pigeon circovirus (PiCV) is still unknown, but it is regarded as an immunosuppressant. This study aimed to find a correlation between PiCV natural infection and immunosuppression. The study was conducted with 56 pigeons divided into the following groups: PiCV-positive but showing (group S) or not (group I) non-specific clinical symptoms and asymptomatic pigeons negative for PiCV (group H). The percentage and apoptosis of T CD3+ and B IgM+ splenocytes; the expression of CD4, CD8, and IFN-\u03b3 genes in splenic mononuclear cells; the number of PiCV viral loads in the bursa of Fabricius; and the level of anti-PiCV antibodies were analyzed. The results showed that the percentage of B IgM+ cells was almost two-fold lower in group S than in group H, and that ca. 20% of the lymphocytes were apoptotic. No increased apoptosis was detected in TCD3+ subpopulation. The PiCV viral loads were approximately one thousand and ten thousand times higher in group S than in groups I and H, respectively. Our results indicate a possible correlation between the number of PiCV viral loads and severity of PiCV infection and confirm that PiCV infection leads to the suppression of humoral immunity by inducing B lymphocyte apoptosis.<\/jats:p>","DOI":"10.3390\/pathogens9080632","type":"journal-article","created":{"date-parts":[[2020,8,3]],"date-time":"2020-08-03T09:02:48Z","timestamp":1596445368000},"page":"632","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":23,"title":["The Clinical Infection with Pigeon Circovirus (PiCV) Leads to Lymphocyte B Apoptosis But Has No Effect on Lymphocyte T Subpopulation"],"prefix":"10.3390","volume":"9","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-6268-9841","authenticated-orcid":false,"given":"Tomasz","family":"Stenzel","sequence":"first","affiliation":[{"name":"Department of Poultry Diseases, Faculty Veterinary Medicine, University of Warmia and Mazury in Olsztyn, 10-719 Olsztyn, Poland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6425-1202","authenticated-orcid":false,"given":"Daria","family":"Dziewulska","sequence":"additional","affiliation":[{"name":"Department of Poultry Diseases, Faculty Veterinary Medicine, University of Warmia and Mazury in Olsztyn, 10-719 Olsztyn, Poland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4711-1619","authenticated-orcid":false,"given":"Bart\u0142omiej","family":"Tyka\u0142owski","sequence":"additional","affiliation":[{"name":"Department of Microbiology and Clinical Pathology, Faculty of Veterinary Medicine, University of Warmia and Mazury in Olsztyn, 10-719 Olsztyn, Poland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Andrzej","family":"Koncicki","sequence":"additional","affiliation":[{"name":"Department of Poultry Diseases, Faculty Veterinary Medicine, University of Warmia and Mazury in Olsztyn, 10-719 Olsztyn, Poland"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2020,8,3]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"2469","DOI":"10.1007\/s007050070002","article-title":"Cloning and sequencing of columbid circovirus (CoCV), a new circovirus from pigeons","volume":"145","author":"Mankertz","year":"2000","journal-title":"Arch. 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