Histopathological Lung Findings in COVID-19 B.1.617.2 SARS-CoV-2 Delta Variant

• Published in: Journal of personalized medicine Vol. 13; no. 2; p. 279
• Main Authors: Jeican, Ionuț Isaia, Inișca, Patricia, Gheban, Dan, Anton, Vlad, Lazăr, Mihaela, Vică, Mihaela Laura, Mironescu, Daniela, Rebeleanu, Codrin, Crivii, Carmen Bianca, Aluaș, Maria, Albu, Silviu, Siserman, Costel Vasile
• Format: Journal Article
• Language: English
• Published: Switzerland MDPI AG 31.01.2023; MDPI
• Subjects: Alveoli; Analysis; Autopsies; Autopsy; B.1.617.2; Biopsy; Coronaviruses; COVID-19; Delta variant; Edema; Endothelial cells; Ethylenediaminetetraacetic acid; Genomes; Health aspects; Histopathology; Immunohistochemistry; Infections; Legal medicine; lung; Medical research; Medicine, Experimental; Mutation; Precision medicine; Protein binding; Proteins; Severe acute respiratory syndrome coronavirus 2; Spike protein; Thrombosis; Virology; United Kingdom; Netherlands; Romania; South Korea; United States > US; Germany; COVID-19; lung; histopathology; Delta variant; B.1.617.2
• ISSN: 2075-4426; 2075-4426
• DOI: 10.3390/jpm13020279

The Delta variant (Pango lineage B.1.617.2) is one of the most significant and aggressive variants of SARS-CoV-2. To the best of our knowledge, this is the first paper specifically studying pulmonary morphopathology in COVID-19 caused by the B.1.617.2 Delta variant. The study included 10 deceased patients (40-83 years) with the COVID-19 Delta variant. The necrotic lung fragments were obtained either by biopsy (six cases) or autopsy (four cases). Tissue samples were subjected to virology analysis for identification of the SARS-CoV-2 variant, histopathology, and immunohistochemistry (anti-SARS coronavirus mouse anti-virus antibody). Virology analysis identified B.1.617.2 through genetic sequencing in eight cases, and in two cases, specific mutations of B.1.617.2 were identified. Macroscopically, in all autopsied cases, the lung had a particular appearance, purple in color, with increased consistency on palpation and abolished crepitations. Histopathologically, the most frequently observed lesions were acute pulmonary edema (70%) and diffuse alveolar damage at different stages. The immunohistochemical examination was positive for proteins of SARS-CoV-2 in 60% of cases on alveolocytes and in endothelial cells. The histopathological lung findings in the B.1.617.2 Delta variant are similar to those previously described in COVID-19. Spike protein-binding antibodies were identified immunohistochemically both on alveolocytes and in the endothelial cells, showing the potential of indirect damage from thrombosis.