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Background and objectives ANCA-associated vasculitis is commonly found in elderly patients, but there are few data concerning outcome and treatment in the highest age groups.Design, setting, participants, & measurements Consecutive patients (N=151) presenting between 1997 and 2009 were retrospectively included from local registries in six centers in Sweden, the United Kingdom, and the Czech Republic if diagnosed with microscopic polyangiitis or granulomatosis with polyangiitis at age $75 years during the study period. Patients were followed until 2 years from diagnosis or death. Data on survival and renal function were analyzed with respect to age, sex, ANCA specificity, renal function, C-reactive protein, comorbidities, and Birmingham Vasculitis Activity Score at diagnosis as well as treatment during the first month.Results Median follow-up was 730 days (interquartile range, 244-730). Overall 1-year survival was 71.5% and 2-year survival was 64.6%. Older age, higher creatinine, and lower Birmingham Vasculitis Activity Score were associated with higher mortality in multivariable analysis. Patients who were not treated with standard immunosuppressive therapy had significantly worse survival. Renal survival was 74.8% at 1 year. No new cases of ESRD occurred during the second year. High creatinine at diagnosis was the only significant predictor of renal survival in multivariable analysis.Conclusions ANCA-associated vasculitis is a disease with substantial mortality and morbidity among elderly patients. This study showed a better prognosis for those who received immunosuppressive treatment and those who were diagnosed before having developed advanced renal insufficiency.

Detection of antineutrophil cytoplasmic antibodies (ANCA) has become a useful tool in the diagnosis of Wegener's granulomatosis and microscopic polyangiitis. However, the results obtained with indirect immunofluorescence (IIF) and by ELISA for ANCA demonstration do not always correlate. A possible explanation for this finding could be that proteins are denatured during the process of antigen purification or during coating onto the solid phase. To avoid this possibility, a monoclonal antibody to PR3 that is precoated on the plate can be used. In the present study we have used the monoclonal antibody (MoAb) 4A3 for the capture of PR3 in an ELISA, and a clinical evaluation of the diagnostic properties of the new capture ELISA has been made. The sensitivity of the capture PR3-ANCA ELISA was 85% in a material of c-ANCA positive sera. A specificity of 90% was obtained in analyses from patients having various forms of glomerulonephritis. There was a significantly higher diagnostic sensitivity of the capture PR3-ANCA ELISA (85%) compared to c-ANCA by IIF (58%) in patients with Wegener's granulomatosis with renal involvement. Capture PR3-ANCA and direct ELISA for MPO-ANCA together gave a diagnostic sensitivity of 98%, versus 75% using IIF. In conclusion, the capture PR3-ANCA ELISA seems to be a valuable tool in the diagnosis of Wegener's granulomatosis with renal involvement. Preliminary data suggest that the technique may have an advantage over direct ELISA for PR3-ANCA, as well as in the follow-up of c-/PR3-ANCA associated vasculitides. However, further prospective studies are needed to clarify this premise.

Abstract. Wegener granulomatosis (WG) and microscopic polyangiitis (MP), diseases associated with antineutrophil cytoplasmic antibodies (ANCA), had an extremely poor prognosis before the introduction of cyclophosphamide and corticosteroids for their treatment. However, there is still reduced patient survival, and some studies have documented severe side effects of the immunosuppressants used. This 10-yr follow-up study assessed 117 consecutive patients with WG or MP with biopsy-confirmed renal involvement. The cumulative relative patient survival was lower: 0.664 for women and 0.648 for men. The causes of death (n ϭ 64) were in most cases registered as associated with the vasculitic disease. Analysis of possible predictive factors for patient survival by multiple Cox regression analysis revealed that a very high level of proteinase 3 (PR3)-ANCA measured by the capture ELISA method, a diagnosis of MP, and older age were factors predicting poorer patient survival. High levels of B-thrombocytes at time of diagnosis were associated with a better prognosis. For patients surviving the first year, remission-sustaining therapy with azathioprine for longer than 12 mo was associated with improved patient survival. Thirty-nine patients developed end-stage renal failure. Elevated serum creatinine at time of diagnosis and a very high level of PR3-ANCA by capture ELISA were factors predicting a higher risk for renal failure during follow-up. The epitope on PR3 assessed by capture ELISA needs to be further analyzed and explored: it seemed to implicate poorer patient and renal survival in WG or MP with renal involvement.

Aim: In this study, we employed chimeric human/mouse Proteinase 3 (PR3) proteins as tools to induce an autoantibody response to PR3 in rats and mice. Method: Rats and mice were immunised with recombinant human PR3 (HPR3), recombinant murine PR3 (mPR3), single chimeric human/mouse PR3 (HHm, HmH, mHH, mmH, mHm, Hmm) or pools of chimeric proteins. Antibodies to mPR3 and HPR3 were measured by ELISA. Antibodies to rat PR3 were determined by indirect immunofluorescence (IIF) on rat white blood cells. Urinalysis was performed by dipstick analysis. Kidney and lung tissue was obtained for pathological examination. Results: In mice, immunisation with the chimeric human/mouse PR3 Hmm led to an autoantibody response to mPR3. Rats immunised with the chimeric human/mouse PR3 Hmm, HmH and mmH, or a pool of the chimeric human/mouse PR3 proteins, produced antibodies selectively binding to rat granulocytes as detected by IIF. No gross pathological abnormalities could be detected in kidney or lungs of mice or rats immunised with chimeric human/mouse PR3. Conclusion: Immunisation with chimeric human/mouse proteins induces autoantibodies to PR3 in rats and mice. Chimeric proteins can be instrumental in developing experimental models for autoimmune diseases. W egener's granulomatosis (WG) is associated with antineutrophil cytoplasmic antibodies (ANCA), 1 in particular to Proteinase 3 (PR3).2 PR3-ANCA are a specific and sensitive marker for WG, whereas other ANCAassociated vasculitides are associated with antimyeloperoxidase (MPO) antibodies. 3 The association between fluctuations in PR3-ANCA and relapsing disease in WG suggests a pathogenic role for PR3-ANCA. 4 However, although animal models support a pathogenic role for MPO-ANCA in vasculitis development 5 attempts to develop an animal model for PR3-ANCA-associated vasculitis have not been successful thus far. 6 Recently, chimeric Pr3 proteins that are partly composed of the human amino acid sequence and partly of the sequence of the mouse homologue have been described. 7 In this study, we employed these chimeric proteins as immunological tools to induce an autoantibody response in rats and mice to PR3. We hypothesised that, by epitope spreading, 8 antibodies could develop to rat or mouse PR3 leading to an autoimmune response to PR3. As the homology between rat and mouse PR3 is 94%, antibodies to mouse PR3 will likely also recognise rat PR3. 9In a set of experiments, rats and mice were immunised with separate chimeric human/mouse PR3 proteins or combinations thereof. Indeed, rats immunised with chimeric human/mouse PR3 developed autoantibodies to mouse PR3 and rat granulocytes and mice immunised with one specific chimeric human/ mouse PR3 induced antibodies to mouse PR3. The results provide the first evidence that an autoantibody response can be generated in rats and mice by immunisation with chimeric proteins. MATERIALS AND METHODS AnimalsExperiments were performed in conventionally housed 10-week-old female Wistar Kyoto (WKY) rats, Brown Norway (BN) rats and C57BL/6J mice (Harl...

SUMMARYAutoantibodies against proteinase 3 (PR3) and myeloperoxidase (MPO) (ANCA = anti-neutrophil cytoplasmic antibodies) are used as diagnostic tools for patients with small vessel vasculitis. ANCA are detected by different assays, but the correlation between the results of these assays is generally poor. The overall aim of the study was to provide a framework for the future development of new assays with an increased diagnostic yield. In order to express discrete epitopes of human PR3 (hPR3), the nonantigenic molecules murine PR3 (mPR3) and human leucocyte elastase (HLE) were used as a framework. We constructed recombinant chimeric vectors and were able to produce 6 hPR3/mPR3 proteins and 3 hPR3/HLE proteins. Anti-PR3 monoclonal antibodies differed in their binding pattern to the chimeras, but no distinct binding region could be identified for any monoclonal antibody. The recombinant hPR3/ mPR3 were also tested in ELISA with sera from patients with Wegener's granulomatosis with renal involvement. The results show that patients have antibodies to different constructs, indicating that the patients vary in their antibody repertoire from the beginning of the disease, and that patients may have antibodies from a broad range of clones early in the course of the disease. Recombinant hPR3/mPR3 chimeric proteins have a potential to be used as antigens in future ANCA assays.

When applying the Chapel Hill nomenclature, PAN is a rare but severe disease with a high incidence of renal involvement and frequent relapses.

Background In ANCA vasculitis, the anaphylatoxin C5a amplifies neutrophil influx and activation through C5aR. CCX168, an oral specific C5aR antagonist, is in clinical development for ANCA-associated renal vasculitis (AARV). Objectives A Phase 2 clinical trial was conducted to investigate the potential of CCX168 to contribute to disease remission and permit glucocorticoid reduction or avoidance in patients with active AARV receiving cyclophosphamide (CYC). Methods This randomized, double-blind, placebo-controlled Phase 2 trial was performed in a stepwise manner. In Step 1 (N=12), CCX168+CYC+low dose prednisone (20 mg/day starting dose) was compared to standard-of-care (SOC) (CYC+high dose prednisone, 60 mg/day starting dose). In Step 2 (N=14), CCX168+CYC and no prednisone was compared to SOC. Eligible patients had GPA, MPA, or renal limited vasculitis, were PR3 or MPO-ANCA positive, and had active renal vasculitis with a GFR >30ml/min. The dose of CCX168 was 30 mg BID PO for 12 weeks and the dose of CYC was 15 mg/kg IV q2-3 wks. Results Baseline characteristics and efficacy results at Week 12 are shown in the table. The number of steroid rescue events was not higher in the CCX168 groups compared to SOC. The incidence of renal remission was higher in the CCX168 groups compared to the SOC control group. The percent decrease from baseline in BVAS, urinary ACR and urinary MCP-1/creatinine was higher in the CCX168 groups compared to SOC. Renal function, as measured by eGFR, increased in all 3 groups, with the largest increase (6.8 mL/min/1.73 m2) in the CCX168+low dose steroids group. CCX168 appeared to be well tolerated. No unexpected serious adverse reactions were observed with CCX168 use. There was one early withdrawal from study, in the control, SOC, group. Parameter CCX168+CYC+Low-Dose Steroids CCX168+CYC+No Steroids Standard of Care: CYC+High-Dose Steroids (N=8) (N=8) (N=9) Demographics and baseline characteristics  Age, mean (SD); Male/Female (%) 55 (15); 50:50 58 (14); 50:50 55 (16); 70/30  Newly diagnosed/relapsing disease (%) 75/25 87.5/12.5 70/30  MPO/PR3+ ANCA (%) 62.5/37.5 50/37.5 40/60  BVAS version 3, mean (SD) 13 (8) 14 (8) 9 (4)  eGFR, mL/min/1.73 m2, mean (SD) 52 (18) 57 (25) 57 (15) Efficacy results  Steroid rescue events 0 1 (13%) 1 (11%)  Renal remission* 6 (75%) 5 (63%) 4 (44%)  U-ACR mean % change** −63% −59% −9%  eGFR mean (SE) change (mL/min/1.73 m2) 6.8 (2.1) 0.6 (3.6) 2.2 (3.3)  Urinary MCP-1/creatinine mean % change** −72% −52% −37%  BVAS mean (SE) % change** −71 (9)% −65 (11)% −26 (25)% *Renal remission is defined as a reduction from baseline in urinary RBCs and improvement in renal function based on eGFR. **Based on ratio of geometric means of Wk12:Baseline. Conclusions CCX168 plus CYC appear to be at least as effective, if not more effective, as full dose steroids plus CYC in treatment of patients with an ANCA associated renal vasculitis flare. Disclosure of Interest D. Jayne Consultant for: ChemoCentryx, Inc., A. Bruchfeld Consultant for...