Comparative analysis of inflammatory responses in lung tissue of K18-hACE2 transgenic mice infected with SARS-CoV-2 prototype and variant strains
10.13200/j.cnki.cjb.004465
- VernacularTitle:SARS-CoV-2原型株及变异株感染K18-hACE2转基因小鼠肺组织炎性反应的比较
- Author:
SUN Kaili
- Publication Type:Journal Article
- Keywords:
SARS-CoV-2;
Prototype strain;
Variant strain;
Inflammatory responses;
Cytokines
- From:
Chinese Journal of Biologicals
2025;38(04):407-412
- CountryChina
- Language:Chinese
-
Abstract:
Objective To compare the immune responses in lung tissue of K18-hACE2 transgenic mice infected with SARS-CoV-2 prototype strain Prototype and its variants Delta and Omicron BF.7, so as to provide experimental evidence for the research and development of related drugs. Methods K18-hACE2 transgenic mice were infected with Prototype, Delta or Omicron BF.7 by nasal drip. On the 7th day after infection, the lung tissues of mice were taken aseptically for subsequent analyses. Viral RNA copy numbers and cytokine gene expression levels in the lung tissues were quantified by qPCR. Histopathological examination of lung tissue damage was performed using HE staining. Results The copy number of viral nucleic acid in lung tissue of mice in Delta group was significantly higher than that in Prototype and Omicron BF.7 groups(t = 5. 419-6. 908, each P < 0. 01), the expression levels of interferon γ(IFN γ)and interleukin-13(IL-13)in lung tissue were significantly higher than those in Prototype and Omicron BF.7 groups(t = 3. 990-7. 282, each P < 0. 05), and the expression levels of tumor necrosis factor-α(TNF-α),and IL-5 were significantly higher than those in Prototype group(t = 7. 108 and 2. 908,each P < 0. 05). In addition, obvious pathological changes related to virus infection were observed in lung tissue sections of mice in three groups. Conclusion Delta variant strain induced the strongest inflammatory response in lung tissue of K18-hACE2 transgenic mice with the highest pathogenicity, followed by prototype strain and Omicron BF.7 variant strain.
