P. Gionchetti et al., LACK OF EFFECT OF ANTINEUTROPHIL CYTOPLASMIC ANTIBODIES ASSOCIATED WITH ULCERATIVE-COLITIS ON SUPEROXIDE ANION PRODUCTION FROM NEUTROPHILS, Gut, 40(1), 1997, pp. 102-104
Background-Antineutrophil cytoplasmic antibodies (ANCAs) from patients
with vasculitidis can induce neutrophils to release oxygen radicals i
n vitro. ANCAs with a perinuclear pattern of immunefluorescence are fo
und in most patients with ulcerative colitis, but several findings are
against ANCAs having a pathogenetic role in this disease. Aims-To eva
luate the influence of ANCAs associated with ulcerative colitis on the
respiratory burst activity of neutrophils. Patients-Serum samples wer
e obtained from 14 patients with ulcerative colitis, seven of whom sho
wed positivity for p-ANCAs, three patients with vasculitidis, two with
positivity for p-ANCAs, and one for c-ANCAs, and seven healthy volunt
eers. Methods-A positive ANCA serology was determined with a standard
indirect immunofluroescence assay. Purified immunoglobulins (IgGs) wer
e prepared from serum samples by DEAE-Affigel blue chromatography. Hum
an neutrophils were prepared by dextran-Ficoll-Hypaque separation. Sup
eroxide anion (O-2-(.)) generation was measured by following the super
oxide dismutase inhibitable reduction of ferricytochrome. Results-Ther
e were no significant differences among samples from ulcerative coliti
s IgG p-ANCA positive, ulcerative colitis IgG p-ANCA negative patients
, and controls on O-2-(.) production, whereas ANCA positive IgG from v
asculitidis significantly enhanced O-2-(.) release (p<0.001). Conclusi
ons-p-ANCAs associated with ulcerative colitis have no effect on the r
espiratory burst activity of normal human neutrophils in vitro. These
results reinforce the hypotheses that ANCAs are unlikely to contribute
to the pathogenesis of ulcerative colitis.