Quinine-dependent antibodies to neutrophils react with a 60-Kd glycoprotein on which neutrophil-specific antigen NB1 is located and an 85-Kd glycosyl-phosphatidylinositol-linked N-glycosylated plasma membrane glycoprotein

Abstract

We have previously described a 24-year-old woman with quinine-dependent antibodies that reacted with neutrophils, red blood cells (RBCs), platelets, and T lymphocytes. The drug-dependent neutrophil antibody was found to react with 85- and 60-Kd neutrophil membrane molecules. In these studies, we further characterized these molecules and found that both were glycosyl-phosphatidylinositol (GPI)-linked and contained sialic acid residues and N-linked carbohydrate side chains, but neither contained O-linked carbohydrates. The protein backbone of the 60-Kd molecule was 45 Kd, and the 85 Kd glycoprotein (GP) was made up of 33- and 31-Kd proteins. While some GPI-anchored neutrophil GPs are released by stimulated neutrophils, neither the 85- nor the 60-Kd GP was released by neutrophil stimulated with C5a, f-met-leu-phe (FMLP), or phorbol myristate acetate (PMA). Neutrophil-specific antigen NB1 is located on a 58- to 64-Kd GP. To determine if the quinine-dependent antibody and anti-NB1 recognize the same GP, immunoprecipitation studies were performed with the quinine-dependent antibody using neutrophils with varying NB1 phenotypes. The 60-Kd GP was detected on NB1-positive neutrophils from 11 of 12 donors tested, but not on NB1- negative neutrophils from two donors tested. After solubilized 125I- labeled neutrophils were absorbed with anti-NB1, the quinine-dependent antibody immunoprecipitated the 85-Kd GP, but not the 60-Kd GP. These results indicate that anti-NB1 and the quinine-dependent antibody identified the same GP. The 85-Kd GP was detected on neutrophils from all 14 donors tested. The electrophoretic mobility of the 85-Kd GP was similar to the electrophoretic mobility of the major 125I-labeled neutrophil protein.

Immune mediated agranulocytosis and anemia associated with thymoma

“…There have been other reports of patients with multiple autoantibodies directed to blood cells [3,4,21]. These include patients with drug-dependent cytopenias [20,22,23].…”

Human neutrophil alloantigens

“…HNA-2 alloantibodies have been associated with TRALI [54] and their pathogenetic relevance confirmed in an ex vivo lung model [50]. Like the Fc γ RIIIb, the CD177 glycoprotein can form neoantigens with drugs or their metabolites that can be recognized by drug-dependent neutrophil antibodies [55].…”

Human neutrophil antigen‐2a expression on neutrophils from healthy adults in western Japan

“…H uman neutrophil antigen-2a (HNA-2a), also known as neutrophil-specific antigen NB1 and CD177, is a 56-to 64-kDa glycosylphosphatidylinositol (GPI)-anchored plasma membrane glycoprotein. 1,2 It is found not only on the membrane, but also intracellularly on the membranes of vesicles and specific granules. 3 This antigen is expressed on subpopulations of neutrophils.…”