A multi well plate with blood samples. Credit: Getty Images

Researchers have shown that SARS-CoV-2 can infect and replicate in lung tissues derived from human-induced pluripotent stem cells1. The virus induces massive inflammation, triggering fibrosis and the death of lung tissues.

The cell-based system could serve as a model to investigate the pathogenetic mechanisms of SARS-CoV-2 infection, says a team at Eyestem Research in Bangalore.

To date, there are no antivirals available to treat COVID-19. The lack of a cell-based model is a major obstacle to developing a therapy.

To better understand COVID-19 pathogenesis, the scientists cultured stem cells which differentiated into various types of lung tissues. The lung cells were then infected with the virus that use the spike protein to enter host cells.

The team, which included researchers at the University of Trans‐Disciplinary Health Sciences and Technology in Bangalore and the Translational Health Science and Technology Institute in Faridabad, detected the virus by using an antibody specific to the spike protein.

Analysis of the infected cells revealed a strong and consistent expression of specific host receptor proteins that help the virus to enter cells and proliferate. Identification of molecular markers, including some faulty genes, pointed towards mitochondrial damage, a key factor in severe COVID-19 infection.

The model shows cell damage and inflammatory responses similar to those seen in COVID‐19-positive lung tissues and could be used to discover and test therapeutic drugs against the disease, say the researchers.