Gm. Maher et Kr. Hartman, DETECTION OF ANTINEUTROPHIL AUTOANTIBODIES BY FLOW-CYTOMETRY - USE OFUNFIXED NEUTROPHILS AS ANTIGENIC TARGETS, Journal of clinical laboratory analysis, 7(6), 1993, pp. 334-340
Antineutrophil antibodies may be found in the sera of patients with ch
ronic neutropenia as well as in the sera of a variety of patients with
neutropenia and associated autoimmune or infectious disorders. We eva
luated an immunofluorescent flow cytometric technique for the measurem
ent of antineutrophil antibodies in serum. Sera from patients with sus
pected immune neutropenia were studied and compared with a group of se
ra from normal healthy individuals, as well as with sera from patients
with rheumatoid arthritis and systemic lupus erythematosus. Of 159 pa
tients with suspected immune neutropenia and a variety of associated c
linical disorders, 59 (37%) were found to have evidence for enhanced b
inding of IgG to normal target neutrophils, interpreted as positive fo
r antineutrophil antibodies. Whereas 0/37 nonneutropenic patients with
typical RA had positive results, 51/244 (21%) of sera from nonneutrop
enic patients with SLE or other collagen vascular disorders showed enh
anced IgG binding to neutrophils. Living neutrophils were used to stud
y the effects of cellular activation, and increased antibody binding w
as observed with certain sera that contained IgG directed against acti
vation-dependent antigens. We found that, under controlled conditions,
flow cytometry can be reliably used to detect antineutrophil autoanti
bodies, with unfixed, living neutrophils as antigenic targets. (C) 199
3 Wiley-Liss, Inc.