“In the blood of the long COVID patients, the team [at the University of Alberta] found higher levels of various proteins related to systemic inflammation—especially galectin-9 and artemin.. higher levels of galectin-9 in patients are associated with increased inflammation and brain fog.. higher levels of artemin are associated with widespread pain, more severe pain and cognitive impairment.. galectin-9 is shed by stressed neutrophils—the most abundant white blood cells—in long COVID patients. This released galectin-9 can promote chronic inflammation by affecting various immune cells.. long COVID dysregulates the production of red blood cells, which results in an abundance of immature red blood cells in the blood of these patients. Normally, immature red blood cells are present in the bone marrow but not in the blood of healthy people. It is these immature red blood cells in the blood that suppress the immune system and contribute to the elevation of artemin in the plasma of long-COVID patients."