{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,29]],"date-time":"2026-09-29T03:06:28Z","timestamp":1790651188745,"version":"4.1.0"},"reference-count":27,"publisher":"MDPI AG","issue":"7","license":[{"start":{"date-parts":[[2023,7,9]],"date-time":"2023-07-09T00:00:00Z","timestamp":1688860800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Italian Ministry of Health"},{"name":"ondazione IRCCS Ca\u2019 Granda Ospedale Maggiore Policlinico"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Microorganisms"],"abstract":"<jats:p>The global outbreak of human monkeypox virus (hMPXV1) in 2022 highlighted the usefulness of dermatological manifestations for its diagnosis. Infection by the human monkeypox virus thus necessitated inclusion in the diagnostic repertoire of dermatopathology. To assess the histopathological and microscopical findings of cutaneous lesions related to hMPXV infection, we analyzed skin biopsies from patients with positive MPXV DNA polymerase chain reaction presenting with a typical course of hMPXV1 infection. The most prominent histopathological findings were ascribable to a pustular stage in which epidermal necrosis with areas of non-viable keratinocytes and a \u201cshadow cell\u201d appearance were evident; in some cases, the deep portion of the hair follicle and the acrosyringial epithelium were affected. The main cytopathic modifications included ballooning keratinocytes, followed by Guarnieri bodies and a ground glass appearance of the keratinocytes\u2019 nuclei, together with a dense mixed inflammatory cell infiltrate with prominent neutrophil exocytosis. Transmission electron microscopy analysis demonstrated viral particle aggregates in the cytoplasm of keratinocytes, without any involvement of the nucleus. Interestingly, we also found the presence of viral particles in infected mesenchymal cells, although to a lesser extent than in epithelial cells. Through this study, we contributed to expanding the histological and microscopic knowledge of the human mpox virus, a key step to understanding current and potential future trends of the disease, as well as of other Orthopoxvirus infections.<\/jats:p>","DOI":"10.3390\/microorganisms11071781","type":"journal-article","created":{"date-parts":[[2023,7,10]],"date-time":"2023-07-10T00:45:37Z","timestamp":1688949937000},"page":"1781","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":29,"title":["Monkeypox: A Histopathological and Transmission Electron Microscopy Study"],"prefix":"10.3390","volume":"11","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-0060-5870","authenticated-orcid":false,"given":"Chiara","family":"Moltrasio","sequence":"first","affiliation":[{"name":"Dermatology Unit, Fondazione IRCCS Ca\u2019 Granda Ospedale Maggiore Policlinico, 20122 Milan, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2313-9585","authenticated-orcid":false,"given":"Francesca Laura","family":"Boggio","sequence":"additional","affiliation":[{"name":"Pathology Unit, Fondazione IRCCS Ca\u2019 Granda Ospedale Maggiore Policlinico, 20122 Milan, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7015-8319","authenticated-orcid":false,"given":"Maurizio","family":"Romagnuolo","sequence":"additional","affiliation":[{"name":"Dermatology Unit, Fondazione IRCCS Ca\u2019 Granda Ospedale Maggiore Policlinico, 20122 Milan, Italy"},{"name":"Department of Pathophysiology and Transplantation, Universit\u00e0 Degli Studi di Milano, 20122 Milan, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2670-3532","authenticated-orcid":false,"given":"Rachele","family":"Cagliani","sequence":"additional","affiliation":[{"name":"Scientific Institute IRCCS E. MEDEA, Bioinformatics, 23842 Bosisio Parini, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2267-5266","authenticated-orcid":false,"given":"Manuela","family":"Sironi","sequence":"additional","affiliation":[{"name":"Scientific Institute IRCCS E. MEDEA, Bioinformatics, 23842 Bosisio Parini, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Alessandra","family":"Di Benedetto","sequence":"additional","affiliation":[{"name":"Dermatology Unit, Fondazione IRCCS Ca\u2019 Granda Ospedale Maggiore Policlinico, 20122 Milan, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8160-4169","authenticated-orcid":false,"given":"Angelo Valerio","family":"Marzano","sequence":"additional","affiliation":[{"name":"Dermatology Unit, Fondazione IRCCS Ca\u2019 Granda Ospedale Maggiore Policlinico, 20122 Milan, Italy"},{"name":"Department of Pathophysiology and Transplantation, Universit\u00e0 Degli Studi di Milano, 20122 Milan, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Biagio Eugenio","family":"Leone","sequence":"additional","affiliation":[{"name":"Department of Medicine and Surgery, University of Milano-Bicocca, 20900 Monza, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Barbara","family":"Vergani","sequence":"additional","affiliation":[{"name":"Department of Medicine and Surgery, University of Milano-Bicocca, 20900 Monza, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2023,7,9]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"782","DOI":"10.3201\/eid2604.191164","article-title":"Human-to-human transmission of monkeypox virus, United Kingdom, October 2018","volume":"26","author":"Vaughan","year":"2020","journal-title":"Emerg. 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