The Journal of Immunology, 2007, 178: 101.13.
Copyright © 2007 by The American Association of Immunologists, Inc.
Increased nitric oxide production by peripheral blood monocytes and selective elevation of serum IgE in patients with systemic lupus erythematosus (SLE).
Dalia Khalifa1,
Patricia Chimezie4,
Soojin Ahn4,
Anna Finkielstein2,
George Dimitrios2,
Susan Lee3,
Ellen Ginzler3,
Helen G Durkin2 and
Maja Nowakowski2
1 Pediatrics,
2 Pathology,
3 Medicine, SUNY Downstate Medical Center, 450 Clarkson Ave, Brooklyn, NY, 11203,
4 SUNY Downstate Medical Center, 450 Clarkson Ave, Brooklyn, NY, 11203
Abstract
Prospective studies of patients with SLE have reported a prevalence of clinically apparent coronary artery disease (CAD) of up to 20%, a marked increase compared with the estimated CAD prevalence rate of 3.5% among healthy females 20–35 years (AHA 1997 Heart and Stroke Statistical Update). Nitric oxide is an important mediator of inflammation associated with vascular damage. We measured nitric oxide production by cultures of peripheral blood monocytes (N= 26) from patients with SLE and determined serum immunoglobulin concentrations (N=19). Elevated immunoglobulin concentrations were observed in sera from 8 patients (42%), and 4 individuals had a selective increase in IgE (>100 IU/ml), with other immunoglobulin isotypes in the normal range. Nitric oxide (NO) production by adherent monocyte cultures from patients with SLE was determined on day 7 using a modified colorimetric Griess reaction to measure nitrite, the stable NO metabolite. The results showed activation in 31% of the patients, with nitrite concentrations exceeding the baseline of 2.8µM more than threefold, reaching 8.8 µM. The mechanism of this in vivo activation of blood monocytes among some patients with SLE remains to be established. Activated monocyte-derived nitric oxide may contribute to the development of atherosclerosis and cardiovascular complications seen in many patients with SLE.
