New Biomarker Predicts Who Will Have Severe Coronavirus

Key biomarkers that could help pinpoint patients who are bound to get a severe reaction to COVID-19 infection have been discovered by KAIST researchers.

The findings help physicians provide the right treatments at the right time, potentially saving lives. The findings were published in the journal Frontiers in Immunology.

‘COVID-19 patients showing reduced glucocorticoid receptor expression, increased CXCL8 expression, and excess neutrophil recruitment to the airways could benefit from treatment with glucocorticoids to prevent airway damage. ’

To understand the differences in immune responses, Professor Heung Kyu Lee and PhD candidate Jang Hyun Park from the Graduate School of Medical Science and Engineering at KAIST analyzed RNA sequencing data extracted from each person's airway cells of healthy controls and of mildly and severely ill patients with COVID-19. The data was available in a public database previously published by a group of Chinese researchers.

"Our analyses identified an association between immune cells called neutrophils and special cell receptors that bind to the steroid hormone glucocorticoid," Professor Lee explained. "This finding could be used as a biomarker for predicting disease severity in patients and thus selecting a targeted therapy that can help treat them at an appropriate time," he added.

COVID-19 and Respiratory Distress Syndrome

Severe illness in COVID-19 is linked to acute respiratory distress syndrome (ARDS), excessive airway-damaging inflammation. ARDS accounts for 70% of deaths in fatal COVID-19 infections. This excessive inflammation involves heightened neutrophil recruitment to the airways, but this reaction's mechanism was unclear.

Myeloid cells, a type of immune cell, produced excess amounts of neutrophil-recruiting chemicals in severely ill patients, including a cytokine called tumor necrosis factor (TNF) and a chemokine called CXCL8.

Glucocorticoids and COVID-19

The airway cells in severely ill patients were not expressing enough glucocorticoid receptors. This was correlated with increased CXCL8 expression and neutrophil recruitment. Glucocorticoids are anti-inflammatory agents that could play a role in treating COVID-19.

Using glucocorticoids in early or mild forms of the infection was found to suppress the symptoms, but in severe airway damage cases, the treatment was ineffective.

"Our study could serve as a springboard towards more accurate and reliable COVID-19 treatments," Professor Lee said.

Source: Medindia