Localization of the Human NA1 Alloantigen on Neutrophil Fc-γ-Receptors

The neutrophil-specific-NA antigen system is a biallelic system. It comprises the antigens NA1 and NA2, which in Caucasian populations show a phenotype frequency of 46% and 88%, respectively (1). It is clinically an important system because it may be involved in diseases such as neonatal alloimmune neutropenia and autoimmune neutropenia as well as in blood transfusion reactions such as rigors, fever, and respiratory distress (1,2).