Covid-19 appears to suppress the function of important immune system cells, preventing the body from fighting off the infection, researchers in Hong Kong reported Thursday.

The team at the University of Hong Kong (HKU) said their findings, published in the peer-reviewed journal Immunity, indicate that boosting immune response with certain drugs might help patients recover better. It’s an approach already being tested by several groups.

The researchers looked at the blood of 41 patients treated for coronavirus in Hong Kong early in the pandemic and compared their immune function to that of healthy volunteers.

Immune system cells known as dendritic cells, along with T-cells and natural killer cells in patients with Covid-19 all appeared to be suppressed. All these cells are part of the body’s response to an infection.

“The findings suggested that jump-starting the immune response with early use of drugs with both immune boosting or antiviral activity such as interferon beta-1b could be important in reducing morbidity and mortality of COVID-19,” Yuen Kwok-Yung, who chairs the infectious diseases department at HKU, said in a statement.

One of the drugs tested was interferon beta-1b. It was initially developed as a treatment for multiple sclerosis, but because it targets the body's immune system, it is also being tested in coronavirus patients.