"Glycophorin A the most abundant sialoglycoprotein on erythrocytes engaged neutrophil Siglec-9 a sialic acid-recognizing receptor known to dampen innate immune cell activation. These studies demonstrate a previously unsuspected role for erythrocytes in suppressing neutrophils ex vivo and in vitro and help explain why neutrophils become easily activated after separation from whole blood."xsd:string