Age-related differences in the cytokine profile in the lungs of Syrian hamsters (Mesocricetus auratus) infected with SARS-CoV-2 virus

Cytokine profile and age play a significant role in COVID-19. A hyperinflammatory response caused by proinflammatory cytokines can lead to cytokine storm and tissue damage. And the levels of interferons, which play an essential role in antiviral immunity, decrease with age. In this regard, there is a need to study the age-related characteristics of COVID-19. Syrian hamsters (Mesocricetus auratus) are the primary model objects for studying the SARS-CoV-2 infectious process. Classic laboratory animals such as mice and rats are not infected by this virus. Current research aimed to examine and compare the cytokine profile in the lungs of young (5-month-old) and aging (18-month-old) individuals of Syrian hamsters infected with the SARS-CoV-2 virus. The levels of cytokines were studied by ELISA: TNF-α, as the main proinflammatory cytokine; IL-6, as the predictor of severe COVID-19; INF-α and INF-γ, which are important components of antiviral immunity. The study showed that during COVID-19, the level of the proinflammatory marker TNF-α significantly increased in 5-month-old hamsters, while Il-6 increased in 18-month-old hamsters. Interferon levels were higher in young, healthy animals than in healthy, aging animals.