Increased circulating neutrophils with surface receptor activity for immunoglobulin G in polycythemia vera and myeloid metaplasia

Reports of heterogeneity of IgG receptor activity of normal circulating neutrophils prompted measurements in myeloproliferative disease to determine if dysplasia of the hematic stem cell resulted in an abnormality of this membrane property. IgG receptors were assayed by rosette formation in suspension with human Rh-positive erythrocytes sensitized with high-titer Rh antiserum. IgG receptors were detected on 19 +/- 1.6% (mean +/- SEM) of neutrophils from 45 normal subjects. A significant increase in IgG-receptor-bearing neutrophils was found in polycythemia vera (PV) and myeloid metaplasia (MyM), with values of 70 +/- 3.6% and 69.7 +/- 4.3%, respectively. Normal values were observed in polycythemic states not due to myeloproliferative disease and in chronic myelocytic leukemia. Rosette-forming neutrophils were increased to 52.3 +/- 3.7% in infection and inflammatory disease, but this value was significantly lower than those in PV and MyM. Increased IgG receptors in PV and MyM may be related to the activated state of the neutrophil and may result from an intrinsic cellular abnormality of the proliferating clone or from altered bone marrow release. Quantitation of neutrophil IgG receptors may be of value in the differential diagnosis of PV and MyM and may offer insights into the derangement of hematopoiesis that underlies these myeloproliferative disorders.