{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,25]],"date-time":"2026-08-25T00:37:52Z","timestamp":1787618272183,"version":"build-2736575974"},"reference-count":49,"publisher":"MDPI AG","issue":"4","license":[{"start":{"date-parts":[[2021,4,15]],"date-time":"2021-04-15T00:00:00Z","timestamp":1618444800000},"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>A small number of neonates delivered to women with SARS-CoV-2 infection have been found to become infected through intrauterine transplacental transmission. These cases are associated with a group of unusual placental pathology abnormalities that include chronic histiocytic intervillositis, syncytiotrophoblast necrosis, and positivity of the syncytiotrophoblast for SARS-CoV-2 antigen or RNA. Hofbauer cells constitute a heterogeneous group of immunologically active macrophages that have been involved in transplacental infections that include such viral agents as Zika virus and human immunodeficiency virus. The role of Hofbauer cells in placental infection with SARS-CoV-2 and maternal-fetal transmission is unknown. This study uses molecular pathology techniques to evaluate the placenta from a neonate infected with SARS-CoV-2 via the transplacental route to determine whether Hofbauer cells have evidence of infection. We found that the placenta had chronic histiocytic intervillositis and syncytiotrophoblast necrosis, with the syncytiotrophoblast demonstrating intense positive staining for SARS-CoV-2. Immunohistochemistry using the macrophage marker CD163, SARS-CoV-2 nucleocapsid protein, and double staining for SARS-CoV-2 with RNAscope and anti-CD163 antibody, revealed that no demonstrable virus could be identified within Hofbauer cells, despite these cells closely approaching the basement membrane zone of the infected trophoblast. Unlike some other viruses, there was no evidence from this transmitting placenta for infection of Hofbauer cells with SARS-CoV-2.<\/jats:p>","DOI":"10.3390\/pathogens10040479","type":"journal-article","created":{"date-parts":[[2021,4,15]],"date-time":"2021-04-15T21:35:13Z","timestamp":1618522513000},"page":"479","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":28,"title":["Molecular Pathology Analysis of SARS-CoV-2 in Syncytiotrophoblast and Hofbauer Cells in Placenta from a Pregnant Woman and Fetus with COVID-19"],"prefix":"10.3390","volume":"10","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-3309-8011","authenticated-orcid":false,"given":"Denise","family":"Morotti","sequence":"first","affiliation":[{"name":"Department of Pathology, Papa Giovanni XXIII Hospital, 24127 Bergamo, Italy"},{"name":"Medical Genetics Laboratory, Papa Giovanni XXIII Hospital, 24127 Bergamo, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0899-7613","authenticated-orcid":false,"given":"Massimiliano","family":"Cadamuro","sequence":"additional","affiliation":[{"name":"Department of Molecular Medicine, University of Padova, 35122 Padova, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Elena","family":"Rigoli","sequence":"additional","affiliation":[{"name":"Department of Pathology, Papa Giovanni XXIII Hospital, 24127 Bergamo, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Aurelio","family":"Sonzogni","sequence":"additional","affiliation":[{"name":"Department of Pathology, Papa Giovanni XXIII Hospital, 24127 Bergamo, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Andrea","family":"Gianatti","sequence":"additional","affiliation":[{"name":"Department of Pathology, Papa Giovanni XXIII Hospital, 24127 Bergamo, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Cristina","family":"Parolin","sequence":"additional","affiliation":[{"name":"Department of Molecular Medicine, University of Padova, 35122 Padova, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Luisa","family":"Patan\u00e8","sequence":"additional","affiliation":[{"name":"Obstetrics and Gynecology Department, Papa Giovanni XXIII Hospital, 24127 Bergamo, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7486-8545","authenticated-orcid":false,"given":"David A.","family":"Schwartz","sequence":"additional","affiliation":[{"name":"Department of Pathology, Medical College of Georgia, Augusta University, Augusta, GA 30912, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2021,4,15]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"799","DOI":"10.5858\/arpa.2020-0901-SA","article-title":"An Analysis of 38 Pregnant Women with COVID-19, Their Newborn Infants, and Maternal-Fetal Transmission of SARS-CoV-2: Maternal Coronavirus Infections and Pregnancy Outcomes","volume":"144","author":"Schwartz","year":"2020","journal-title":"Arch. 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