Bone Marrow Failure Disorders

In a letter to the editor published in Blood, researchers from the University of Michigan Medical School and the Johns Hopkins University School of Medicine highlight patient characteristics and reactions to vaccines against COVID-19 among patients with paroxysmal nocturnal hemoglobinuria (PNH). The researchers found that SARS-CoV-2 spike protein subunit 1 (S1) “did not increase hemolysis of PNH erythrocytes as compared with acidified normal human serum alone,” adding that “S1 does not appear to bind erythrocytes.” In conclusion, they wrote, “We postulate that strong complement amplification as a byproduct of the inflammatory response is responsible for the clinically observed hemolysis, as has been reported with other vaccines, infections, and surgeries.”