CpG oligodeoxynucleotide stimulates production of anti-neutrophil cytoplasmic antibodies in ANCA associated vasculitis

Background Wegener's Granulomatosis and Microscopic Polyangiitis are life-threatening systemic necrotizing vasculitides of unknown aetiology. The appearance of circulating antibodies to neutrophil cytoplasmic antigens (ANCA) is strongly associated with the development of the disease. A link between infection and disease has long been suspected, and the appearance of ANCA antibodies has been reported following bacterial and viral infections. The depletion of circulating B cells with monoclonal antibody therapy can induce remission, and this observation suggests a pathogenic role for B cells in this disease. As bacterial DNA is known to induce B cell proliferation and antibody production via TLR-9 stimulation, we have explored the possibility that unmethylated CpG oligodeoxynucleotide, as found in bacterial and viral DNA, may play a role in stimulating circulating autoreactive B cells to produce ANCA in patients with vasculitis. Results We have confirmed that unmethylated CpG oligonucleotide is a potent stimulator of antibody production by PBMC in vitro. The stimulation of PBMC with CpG oligonucleutides resulted in the production of similar amounts of IgG in both ANCA+ patients and normal controls. In spite of this, PR3 ANCA+ patients synthesised significantly higher amount of IgG ANCA than normal controls. In MPO ANCA+ patients, there was a tendency for patients to produce higher amount of ANCA than controls, however, the difference did not reach significance. Furthermore, we were able to detect circulating MPO-reactive B cells by ELISpot assay from the peripheral blood of 2 MPO+ ANCA vasculitis patients. Together, this indicates that circulating anti-neutrophil autoreactive B cells are present in ANCA+ vasculitis patients, and they are capable of producing antibodies in response to CpG stimulation. Of note, CpG also induced the production of the relevant autoantibodies in patients with other types of autoimmune diseases. Conclusion Circulating ANCA autoreactive B cells are present in patients with ANCA+ vasculitis. The production of ANCA from these cells in response to unmethylated CpG stimulation lead us to propose that stimulation of these cells by immunostimulatory DNA sequences such as CpG oligodeoxynucleotide during infection may provide a link between infection and ANCA associated vasculitis. This phenomenon may also apply to other antibody mediated autoimmune diseases.Plinio R Hurtado, Lisa Jeffs, Jodie Nitschke, Mittal Patel, Ghafar Sarvestani, John Cassidy, Pravin Hissaria, David Gillis and Chen Au Pe

Risk factors, health effects and behaviour in older people during extreme heat: A survey in South Australia

Older people had a high incidence of hospitalisation during the 2009 heat wave in South Australia. We sought to explore resilience, behaviours, health risk factors and health outcomes during recent heat waves for a representative sample of independently living residents. A telephone survey of 499 people aged 65 years and over was conducted, and included both metropolitan and rural residences. A variety of adaptive strategies were reported, with 75% maintaining regular appointments and activities during the heat. However, 74% took medication for chronic disease and 25% assessed their health status to be fair to poor. In a multivariate model, factors associated with heat health outcomes included medication for mental health, heart failure, diabetes or respiratory health, reporting a reduced health status, use of mobility aids and being female. Compared with younger participants, those over 75 had more check-up calls and visits by family, friends and neighbours. However, confidence to call on support was associated with indicators of social isolation. The study indicates that older people are generally resilient, but interventions addressing multi-morbidity and medication interactions and social isolation should be developed.Monika Nitschke, Alana Hansen, Peng Bi, Dino Pisaniello, Jonathan Newbury, Alison Kitson, Graeme Tucker, Jodie Avery and Eleonora Dal Grand

CpG oligodeoxynucleotide stimulates production of anti-neutrophil cytoplasmic antibodies in ANCA associated vasculitis-5

D mitogen (PWM) + IL2, or inactivated + IL2. A representative set of results is shown from a PR3ANCA patient (and a MPOANCA patient ().<p><b>Copyright information:</b></p><p>Taken from "CpG oligodeoxynucleotide stimulates production of anti-neutrophil cytoplasmic antibodies in ANCA associated vasculitis"</p><p>http://www.biomedcentral.com/1471-2172/9/34</p><p>BMC Immunology 2008;9():34-34.</p><p>Published online 14 Jul 2008</p><p>PMCID:PMC2483256.</p><p></p

CpG oligodeoxynucleotide stimulates production of anti-neutrophil cytoplasmic antibodies in ANCA associated vasculitis-4

G-B and IL-2. Each patient assay was paired with a healthy control. After 12 days of culture, supernatants were harvested. IgG concentration and supernatant reactivity to either PR3 or MPO was measured by ELISA. The amount of IgG detected in the supernatants was of 5.5 ± 2.2 μg mLin the patients compared to 4.1 ± 1.2 μg mLin the control group (. Figure shows the reactivity of the supernatants from PR3ANCA patients towards PR3 antigen. The difference against control individuals was highly significant (P = 0.0082). Figure shows the reactivity of the supernatants from MPOANCA patients towards MPO antigen. The difference was not significant (P = 0.072) although their supernatants showed a clear tendency towards higher reactivity compared to controls. There was no correlation between patients' serum ANCA titre at the time of the assay and their production of ANCA in response to CpG-B as shown in (r= 0.172).<p><b>Copyright information:</b></p><p>Taken from "CpG oligodeoxynucleotide stimulates production of anti-neutrophil cytoplasmic antibodies in ANCA associated vasculitis"</p><p>http://www.biomedcentral.com/1471-2172/9/34</p><p>BMC Immunology 2008;9():34-34.</p><p>Published online 14 Jul 2008</p><p>PMCID:PMC2483256.</p><p></p

CpG oligodeoxynucleotide stimulates production of anti-neutrophil cytoplasmic antibodies in ANCA associated vasculitis-1

D mitogen (PWM) + IL2, or inactivated + IL2. A representative set of results is shown from a PR3ANCA patient (and a MPOANCA patient ().<p><b>Copyright information:</b></p><p>Taken from "CpG oligodeoxynucleotide stimulates production of anti-neutrophil cytoplasmic antibodies in ANCA associated vasculitis"</p><p>http://www.biomedcentral.com/1471-2172/9/34</p><p>BMC Immunology 2008;9():34-34.</p><p>Published online 14 Jul 2008</p><p>PMCID:PMC2483256.</p><p></p

CpG oligodeoxynucleotide stimulates production of anti-neutrophil cytoplasmic antibodies in ANCA associated vasculitis-0

G-B and IL-2. Each patient assay was paired with a healthy control. After 12 days of culture, supernatants were harvested. IgG concentration and supernatant reactivity to either PR3 or MPO was measured by ELISA. The amount of IgG detected in the supernatants was of 5.5 ± 2.2 μg mLin the patients compared to 4.1 ± 1.2 μg mLin the control group (. Figure shows the reactivity of the supernatants from PR3ANCA patients towards PR3 antigen. The difference against control individuals was highly significant (P = 0.0082). Figure shows the reactivity of the supernatants from MPOANCA patients towards MPO antigen. The difference was not significant (P = 0.072) although their supernatants showed a clear tendency towards higher reactivity compared to controls. There was no correlation between patients' serum ANCA titre at the time of the assay and their production of ANCA in response to CpG-B as shown in (r= 0.172).<p><b>Copyright information:</b></p><p>Taken from "CpG oligodeoxynucleotide stimulates production of anti-neutrophil cytoplasmic antibodies in ANCA associated vasculitis"</p><p>http://www.biomedcentral.com/1471-2172/9/34</p><p>BMC Immunology 2008;9():34-34.</p><p>Published online 14 Jul 2008</p><p>PMCID:PMC2483256.</p><p></p