4259 – Anti-PR3 hs

Intended Purpose

The Anti-PR3 hs is a quantitative immunoassay for the determination of IgG antibodies against proteinase 3 (PR3) in human serum. The Anti-PR3 hs is intended as an aid in the diagnosis of systemic vasculitides (SV) in conjunction with other clinical and laboratory findings. The immunoassay is designed for manual professional in vitro diagnostic use.

Diagnostic Relevance

Anti-neutrophil cytoplasmic antibodies (ANCA) play an important role in the serological diagnosis of SV. These antibodies are usually determined by indirect immunofluorescence (IIF) of ethanol-fixed human neutrophils, in which the pattern of the IIF distinguishes cytoplasmic ANCA (cANCA) and perinuclear ANCA (pANCA). In IIF, the pattern of pANCA is mainly caused by the reactivity of MPO, a cationic protein found in azurophilic granules. MPO autoantibodies occur in a variety of vasculitides such as microscopic polyangiitis, Churg-Strauss syndrome and Polyarteritis nodosa. Autoantibodies to PR3 are a specific serological marker for Wegener’s granulomatosis (WG), especially the strong association of the titres with disease activity and the inhibition of the proteolytic activity of PR3.