COVID-19 lung damage caused by persistence of 'abnormal cells', say scientist

The research also showed the long-term persistence of the viral genome in

respiratory cells and in cells lining the blood vessels, along with the infected

cell syncytia.

COVID-19 lung damage caused by persistence of 'abnormal cells', say scientists

Photo for representation only. Source: iStock.

Scientists have analysed organ samples from deceased COVID-19 patients and found extensive

lung damage in most cases caused by the persistence of abnormal "fused cells," an advance

which sheds more light on the progression of the disease.

The researchers, including those from King's College London in the UK, examined lung, heart,

liver, and kidney samples of 41 patients who died of COVID-19 to examine the behaviour of

the novel coronavirus SARS-CoV-2.

In the study, published in the journal eBioMedicine, they revealed the unique characteristics of

the virus that may explain why some patients experience disease symptoms for months --

known as 'long COVID'—with a feeling of fatigue and lack of breath.

The findings show extensive lung damage in most cases, with patients experiencing profound

disruption of the normal lung structure and the transformation of respiratory tissue into fibrotic

material.

According to the scientists, nearly 90 per cent of the patients showed additional characteristics

that were quite unique to COVID-19 compared to other forms of pneumonia.

They said there was extensive blood clotting of the lung arteries and veins, and several lung

cells were abnormally large with many nuclei, resulting from the fusion of different cells into

single large cells.

The researchers noted that this formation of fused cells—syncytia—is due to the viral spike

protein, which the virus uses to enter the cell.

When the protein is present on the surface of cells infected by the COVID-19 virus, the study

noted that it stimulates their fusion with other normal lung cells, which can be a cause for

inflammation and thrombosis.

The research also showed the long-term persistence of the viral genome in respiratory cells and

in cells lining the blood vessels, along with the infected cell syncytia.

According to the researchers, the presence of these infected cells can cause the major structural

changes observed in lungs, which can persist for several weeks or months, and could eventually

explain 'long COVID'.

"The findings indicate that COVID-19 is not simply a disease caused by the death of virusinfected

cells but is likely the consequence of these abnormal cells persisting for long periods

inside the lungs," said Mauro Giacca, a co-author of the study from King's College London

https://www.tribuneindia.com/news/health/covid-19-lung-damage-caused-by-persistence-ofabnormal-

cells-say-scientists-165949