Sustained Lung Inflammation Post-SARS-CoV-2 Infection in Mice Is Associated with Increased Pulmonary T Cells

Area of Science:

• Immunology
• Virology
• Pulmonology

Background:

• Many SARS-CoV-2 patients suffer from chronic pulmonary issues and inflammation post-infection.
• The exact immunopathology driving these long-term effects is unclear due to limited animal models.

Purpose of the Study:

• To investigate the long-term pulmonary consequences of SARS-CoV-2 infection.
• To establish and utilize a suitable animal model for studying persistent lung inflammation.

Main Methods:

• A genetic cross of 129 mice and B6-K18-hACE2 transgene mice was used.
• Mice were infected with a low dose of ancestral SARS-CoV-2.
• Pulmonary inflammation and immune cell presence were analyzed up to 28 days post-infection.

Main Results:

• Complete viral clearance and weight recovery by day 8 post-infection.
• Prolonged lung and airway inflammation persisted until day 28.
• Inflammation was associated with CD4+ and CD8+ T cells, especially CD8+ effector T cells.

Conclusions:

• The 129xB6-K18-hACE2 mouse model effectively mimics long-term pulmonary inflammation after SARS-CoV-2 infection.
• This model is valuable for understanding the drivers of chronic lung inflammation.
• It can be used to test therapeutic strategies for post-COVID-19 pulmonary complications.