IL-1β production by human polymorphonuclear leucocytes stimulated by anti-neutrophil cytoplasmic autoantibodies: relevance to systemic vasculitis

Abstract

SUMMARYNeutrophils accumulate in the acute blood vessel lesions of patients with autoimmune systemic vasculitis. They have been shown previously to produce the cytokine IL-1¯in response to stimulation with TNF. This study demonstrates that neutrophils can be stimulated by anti-neutrophil cytoplasmic antibodies (ANCA), which are present in patients with systemic vasculitis, to express mRNA and protein for IL-1¯. Both human ANCA and MoAbs to a variety of autoantigens recognized by ANCA, including proteinase 3, myeloperoxidase, bactericidal/permeability increasing protein and elastase, are effective. This response can be inhibited by actinomycin and cycloheximide, suggesting a requirement for de novo protein synthesis. IL-1¯production can be inhibited by pooled human intravenous immunoglobulins but not by FK506 or cyclosporin A. These data suggest that ANCA in patients with active vasculitis may stimulate neutrophils to produce cytokines. It is hypothesized that cytokine production from neutrophils that accumulate in significant numbers in vasculitic lesions contribute to and augment the local inflammatory response by the activation of vascular endothelial cells and infiltrating leucocytes.

Dendritic cell uptake of human apoptotic and necrotic neutrophils inhibits CD40, CD80, and CD86 expression and reduces allogeneic T cell responses: Relevance to systemic vasculitis

“…Human neutrophils were isolated as previously described (37). Neutrophils were washed and resuspended to 5 ϫ 10 6 /ml in Iscove's modified Dulbecco's medium (IMDM; Sigma-Aldrich) supplemented with penicillin/streptomycin and 10% autologous serum.…”

“…Apoptotic neutrophils were resuspended to 5 ϫ 10 6 cells/ml in IMDM containing penicillin/streptomycin, but without serum. IgG was isolated from serum of normal healthy volunteers or from patients with PR3 ANCA or MPO ANCA, using a Hi-trap protein G affinity column (Amersham Pharmacia Biotech) as previously described (37) Quantitation of phagocytosis of neutrophils by DCs. Uptake of apoptotic neutrophils by DCs was assessed using an assay with microscopic quantification to determine macrophage ingestion of apoptotic neutrophils (38,39).…”

Antineutrophil Cytoplasmic Antibodies Induce Reactive Oxygen-Dependent Dysregulation of Primed Neutrophil Apoptosis and Clearance by Macrophages

“…19 Briefly, freshly isolated blood from six healthy donors was mixed with acid citrate dextrose (ACD) in a ratio of 1:10. This was then mixed with an equal volume of 4:5 Hespan (6% Hetastarch in 0.9% sodium chloride) and with 1:5 diluted ACD (diluted with distilled water to 1:10).…”

“…IgG was prepared from patient and normal human donor sera, using a Hi-trap protein G affinity column (Pharmacia) as previously described. 19 All IgG samples were used individually. ANCA specificity was confirmed by Western blot analysis and enzyme-linked immunosorbent assay (data not shown).…”

Cytoplasmic Pattern Anti-neutrophil Cytoplasmic Antibody (cANCA)-positive Cutaneous Leukocytoclastic Vasculitis Induced by Propylthiouracil: A Case Report

“…It has been demonstrated that ANCAs are able to stimulate neutrophils. In vitro, ANCAs can activate neutrophils primed with tumor necrosis factor-alpha (TNF-α) for the production of reactive oxygen intermediates (ROI), the release of lysosomal enzymes, and the secretion of interleukin-1 [1][2][3]. Apart from inducing the activation of neutrophils, ANCAs also activate monocytes and/or endothelial cells [3][4][5].…”