SPECIFICATION

Code	Description
VAS-3-A	PR3、MPO、GBM
VAS-2-A	PR3、MPO

INTENDED USE

The Antibodies against PR3, MPO and GBM Line ImmunoAssay is for the qualitative measurement of IgG class antibodies against PR3, MPO and GBM in human serum. The assay is intended for in vitro diagnostic use only as an aid in the diagnosis of systemic vasculitis, i.e. Wegener’s granulomatosis, and the Goodpasture syndrome.

Proteinase 3 (PR3) is the main target of cytoplasmic antineutrophil cytoplasm antibodies (cANCA). In contrast to that, perinuclear ANCA (pANCA) mainly react with myeloperoxidase (MPO).

cANCA are closely related to Wegener's granulomatosis classically causing severe glomerulonephritis. Repeated examination for cANCA is therefore of value for monitoring of disease activity and effect of treatment.

pANCA, detected by indirect immunofluorescence, can also be found in a lot of diseases apart from vasculitis. Consequently the detection of cANCA and pANCA by indirect immune fluorescence is not sufficient to proof systemic necrotising vasculitis. Therefore it is necessary to analyze the fine specification of PR3-ANCA and MPO-ANCA by ELISA as a second step or in parallel.

Anti-GBM antibodies (anti-glomerular basement membrane antibodies) can be detedted in about 90% of patients with Good pasture's syndrome. While Goodpasture's syndrome is a relatively rare condition (0.5% of all patients with renal diseases), it is rapidly progressive and, if not treated, fatal in 75-90%. An early diagnosis and an immediate and correct treatment decrease the lethality dramatically.

ASSAY PRINCIPLE

The test is based on the principle of the line immune assay (LIA).

PR3, MPO and GBM autoantigens are applied as lines on a nitrocellulose membrane. The nitrocellulose membrane is blocked to prevent unspecific reactions. During incubation of a strip with diluted patient samples, autoantibodies present in the sample will bind to the antigens on the strip. For the detection of the bound antibodies, an alkaline phosphatase labelled anti-human IgG antibody is used. After addition of the substrate solution, the appearance of purple blue lines indicates the existence of (auto) antibodies against the respective antigens.

斯德润诊断

Line Immuno Assay (LIA) for the Detection of Antibodies in Autoimmune Vasculitis