Department of Pathology, School of Medicine, University of São Paulo, São Paulo, Brazil.
Adolfo Lutz Institute, Division of Pathology, São Paulo, Brazil.
J Pathol. 2021 Jul;254(3):239-243. doi: 10.1002/path.5679. Epub 2021 May 21.
The ability of the new coronavirus SARS-CoV-2 to spread and contaminate is one of the determinants of the COVID-19 pandemic status. SARS-CoV-2 has been detected in saliva consistently, with similar sensitivity to that observed in nasopharyngeal swabs. We conducted ultrasound-guided postmortem biopsies in COVID-19 fatal cases. Samples of salivary glands (SGs; parotid, submandibular, and minor) were obtained. We analyzed samples using RT-qPCR, immunohistochemistry, electron microscopy, and histopathological analysis to identify SARS-CoV-2 and elucidate qualitative and quantitative viral profiles in salivary glands. The study included 13 female and 11 male patients, with a mean age of 53.12 years (range 8-83 years). RT-qPCR for SARS-CoV-2 was positive in 30 SG samples from 18 patients (60% of total SG samples and 75% of all cases). Ultrastructural analyses showed spherical 70-100 nm viral particles, consistent in size and shape with the Coronaviridae family, in the ductal lining cell cytoplasm, acinar cells, and ductal lumen of SGs. There was also degeneration of organelles in infected cells and the presence of a cluster of nucleocapsids, which suggests viral replication in SG cells. Qualitative histopathological analysis showed morphologic alterations in the duct lining epithelium characterized by cytoplasmic and nuclear vacuolization, as well as nuclear pleomorphism. Acinar cells showed degenerative changes of the zymogen granules and enlarged nuclei. Ductal epithelium and serous acinar cells showed intense expression of ACE2 and TMPRSS receptors. An anti-SARS-CoV-2 antibody was positive in 8 (53%) of the 15 tested cases in duct lining epithelial cells and acinar cells of major SGs. Only two minor salivary glands were positive for SARS-CoV-2 by immunohistochemistry. Salivary glands are a reservoir for SARS-CoV-2 and provide a pathophysiological background for studies that indicate the use of saliva as a diagnostic method for COVID-19 and highlight this biological fluid's role in spreading the disease. © 2021 The Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.
新型冠状病毒 SARS-CoV-2 的传播和污染能力是 COVID-19 大流行状况的决定因素之一。唾液中一直检测到 SARS-CoV-2，其灵敏度与鼻咽拭子相似。我们对 COVID-19 死亡病例进行了超声引导的尸检活检。获得了唾液腺（SG；腮腺、下颌下腺和小唾液腺）的样本。我们使用 RT-qPCR、免疫组织化学、电子显微镜和组织病理学分析来分析样本，以鉴定 SARS-CoV-2 并阐明唾液腺中的定性和定量病毒特征。该研究包括 13 名女性和 11 名男性患者，平均年龄为 53.12 岁（范围为 8-83 岁）。18 名患者的 30 个 SG 样本中 RT-qPCR 检测到 SARS-CoV-2 呈阳性（占总 SG 样本的 60%，占所有病例的 75%）。超微结构分析显示，SG 管腔衬里细胞的细胞质、腺泡细胞和管腔中存在大小和形状与冠状病毒科一致的 70-100nm 球形病毒颗粒。受感染细胞的细胞器也发生了退化，并且存在核衣壳簇，这表明 SG 细胞中的病毒复制。定性组织病理学分析显示，导管衬里上皮的形态发生改变，特征为细胞质和核空泡化以及核多形性。腺泡细胞显示酶原颗粒和增大的细胞核的退行性变化。导管上皮和浆液腺泡细胞强烈表达 ACE2 和 TMPRSS 受体。在 15 例经测试的主要 SG 导管衬里上皮细胞和腺泡细胞中，有 8 例（53%）抗 SARS-CoV-2 抗体呈阳性。只有两个小唾液腺的 SARS-CoV-2 免疫组织化学呈阳性。唾液腺是 SARS-CoV-2 的储存库，为表明唾液可作为 COVID-19 诊断方法的研究提供了病理生理学背景，并强调了这种生物液在传播疾病中的作用。
