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author:("hipe, Falk")
1.  Active systemic lupus erythematosus is associated with a reduced cytokine production by B cells in response to TLR9 stimulation 
Introduction
Systemic lupus erythematosus (SLE) is an autoimmune disease associated with a break in self-tolerance reflected by a production of antinuclear autoantibodies. Since autoantibody production can be activated via nucleic acid Toll-like receptor 9 (TLR9), the respective pathway has been implicated in the development of SLE and pathogenic B cell responses. However, the response of B cells from SLE patients to TLR9 stimulation remains incompletely characterized.
Methods
In the current study, the response of B cells from SLE patients and healthy donors upon TLR9 stimulation was analyzed in terms of proliferation and cytokine production and correlated with the lupus disease activity and anti-dsDNA titers.
Results
B cells from SLE patients showed a reduced response to TLR9 agonist compared to B cells from healthy donors in terms of proliferation and activation. B cells from SLE patients with higher disease activity produced less interleukin (IL)-6, IL-10, vascular endothelial growth factor, and IL-1ra than B cells from healthy donors. Further analyses revealed an inverse correlation of cytokines produced by TLR9-stimulated B cells with lupus disease activity and anti-dsDNA titer, respectively.
Conclusion
The capacity of B cells from lupus patients to produce cytokines upon TLR9 engagement becomes less efficient with increasing disease activity, suggesting that they either enter an exhausted state or become tolerant to TLR stimulation for cytokine production when disease worsens.
Electronic supplementary material
The online version of this article (doi:10.1186/s13075-014-0477-1) contains supplementary material, which is available to authorized users.
doi:10.1186/s13075-014-0477-1
PMCID: PMC4247768  PMID: 25385499
2.  The protein tyrosine phosphatase PTP1B is a negative regulator of CD40 and BAFF-R signaling and controls B cell autoimmunity 
The protein tyrosine phosphatase PTP1B regulates co-receptor signaling on B cells and thus controls B cell autoimmunity.
Tyrosine phosphorylation of signaling molecules that mediate B cell activation in response to various stimuli is tightly regulated by protein tyrosine phosphatases (PTPs). PTP1B is a ubiquitously expressed tyrosine phosphatase with well-characterized functions in metabolic signaling pathways. We show here that PTP1B negatively regulates CD40, B cell activating factor receptor (BAFF-R), and TLR4 signaling in B cells. Specifically, PTP1B counteracts p38 mitogen-activated protein kinase (MAPK) activation by directly dephosphorylating Tyr182 of this kinase. Mice with a B cell–specific PTP1B deficiency show increased T cell–dependent immune responses and elevated total serum IgG. Furthermore, aged animals develop systemic autoimmunity with elevated serum anti-dsDNA, spontaneous germinal centers in the spleen, and deposition of IgG immune complexes and C3 in the kidney. In a clinical setting, we observed that B cells of rheumatoid arthritis patients have significantly reduced PTP1B expression. Our data suggest that PTP1B plays an important role in the control of B cell activation and the maintenance of immunological tolerance.
doi:10.1084/jem.20131196
PMCID: PMC3949573  PMID: 24590766
3.  Current state and future directions of autologous hematopoietic stem cell transplantation in systemic lupus erythematosus 
Annals of the rheumatic diseases  2011;70(12):2071-2074.
Autologous hematopoietic stem cell transplantation (AHSCT) has been proposed as a treatment modality which may arrest the autoimmune disease process and lead to sustained treatment-free remissions. Since the first consensus statement in 1997, approximately 200 autologous bone marrow or hematopoietic stem cell transplantations have been reported world-wide for SLE. The current state of AHSCT in SLE was reviewed at a recent meeting of the Autoimmune Working Party of the European Group for Blood and Marrow Transplantation. There was general agreement among experts in this field, that in patients with severe SLE refractory to conventional immunosuppressive therapies, AHSCT can achieve sustained clinical remissions (ranging from 50–70% disease free survival at 5 years) associated with qualitative immunological changes not seen with other forms of therapy. However, this clinical benefit is associated with an increase in short-term mortality in most but not all studies. Improving patient selection, long-term follow up of patients after AHSCT, optimization of induction and maintenance therapy along with detailed analysis of the immune system are identified as key areas for future research. Optimally, AHSCT should be compared to conventional therapy in randomized controlled trials. Development of stronger transplant registries, defining a core set of clinical data and standardizing biologic sample collections would make future collaborations and comparison of various studies more feasible.
doi:10.1136/ard.2010.148049
PMCID: PMC3923531  PMID: 21873334
4.  Cell-Specific Type I IFN Signatures in Autoimmunity and Viral Infection: What Makes the Difference? 
PLoS ONE  2013;8(12):e83776.
Gene expression profiling of peripheral blood mononuclear cells (PBMCs) has revealed a crucial role for type I interferon (IFN) in the pathogenesis of systemic lupus erythematosus (SLE). However, it is unclear how particular leucocyte subsets contribute to the overall type I IFN signature of PBMCs and whole blood samples.Furthermore, a detailed analysis describing the differences in the IFN signature in autoimmune diseases from that observed after viral infection has not been performed to date. Therefore, in this study, the transcriptional responses in peripheral T helper cells (CD4+) and monocyte subsets (CD16− inflammatory and CD16+ resident monocytes) isolated from patients with SLE, healthy donors (ND) immunised with the yellow fever vaccine YFV-17Dand untreated controls were compared by global gene expression profiling.It was striking that all of the transcripts that were regulated in response to viral exposure were also found to be differentially regulated in SLE, albeit with markedly lower fold-change values. In addition to this common IFN signature, a pathogenic IFN-associated gene signature was detected in the CD4+ T cells and monocytes from the lupus patients. IL-10, IL-9 and IL-15-mediated JAK/STAT signalling was shown to be involved in the pathological amplification of IFN responses observed in SLE. Type I IFN signatures identified were successfully applied for the monitoring of interferon responses in PBMCs of an independent cohort of SLE patients and virus-infected individuals. Moreover, these cell-type specific gene signatures allowed a correct classification of PBMCs independent from their heterogenic cellular composition. In conclusion, our data show for the first time that monocytes and CD4 cells are sensitive biosensors to monitor type I interferon response signatures in autoimmunity and viral infection and how these transriptional responses are modulated in a cell- and disease-specific manner.
doi:10.1371/journal.pone.0083776
PMCID: PMC3877094  PMID: 24391825
5.  Belimumab Reduces Autoantibodies, Normalizes Low Complement, and Reduces Select B-Cell Populations in Patients With Systemic Lupus Erythematosus 
Arthritis and Rheumatism  2012;64(7):2328-2337.
Objective
To assess the effects of the B-lymphocyte stimulator (BLyS)-specific inhibitor belimumab on immunologic biomarkers, including B- and T-cell populations, and maintenance of antibody titers to prior vaccines in autoantibody-positive systemic lupus erythematosus (SLE) patients.
Methods
Pooled data from two phase 3 trials—BLISS-52 and -76—comparing belimumab 1 or 10 mg/kg vs placebo (each plus standard SLE therapy) were analyzed for changes in autoantibodies, immunoglobulin (Ig), and complement (C); BLISS-76 patients were analyzed for changes in B- and T-cell populations, and effects on prior vaccine-induced antibody levels.
Results
Belimumab-treated patients experienced significant sustained reductions in IgG and autoantibodies, and improvement in C3/C4, resulting in greater positive-to-negative conversion rates for IgG anti–double-stranded DNA (anti-dsDNA), anti-Smith, anticardiolipin, and antiribosomal P autoantibodies, and normalization of hypergammaglobulinemia and low C3/C4. Belimumab-treated patients experienced significant decreases in naïve and activated B cells, as well as plasma cells, whereas memory B cells and T-cell populations did not decrease. Belimumab did not substantially affect pre-existing antipneumococcal or antitetanus antibody levels. Post-hoc analysis showed greater reductions in SLE disease activity and the risk of severe flares in patients treated with belimumab 10 mg/kg (P ≤ 0.01) who were anti-dsDNA positive with low C3/C4 at baseline. Normalization of C3 or anti-dsDNA by 8 weeks, irrespective of therapy, was predictive of a reduced risk of severe flare over 52 weeks.
Conclusion
Belimumab appears to promote normalization of serologic activity and reduce BLyS-dependent B-cell subsets in serologically and clinically active SLE. Greater serologic activity may predict a better treatment response to belimumab.
doi:10.1002/art.34400
PMCID: PMC3350827  PMID: 22275291
7.  Certolizumab pegol plus methotrexate provides broad relief from the burden of rheumatoid arthritis: analysis of patient-reported outcomes from the RAPID 2 trial 
Annals of the Rheumatic Diseases  2011;70(6):996-1002.
Objective
To assess the impact of certolizumab pegol (CZP) on patient-reported outcomes (PROs) in rheumatoid arthritis (RA), and to interpret these results using number needed to treat (NNT), and associations between PRO responses and longer term outcomes.
Methods
A total of 619 patients with active RA were randomised to CZP 200 or 400 mg, or placebo plus methotrexate (MTX). PROs assessed included pain, patient's global assessment of disease activity (PtGA), physical function, fatigue and health-related quality of life. Treatment impact on PROs, NNT to achieve simultaneous improvements in multiple PROs and correlations between PROs were calculated. Times to onset of improvements greater than or equal to minimum clinically important differences (MCIDs) in pain as a determinant of clinical outcomes at week 24 were compared between week 6 and 12 responders, and in patients with improvements in pain ≥MCID at week 12 (week 12 responders/non-responders).
Results
CZP 200 and 400 mg plus MTX were associated with rapid, clinically meaningful improvements in all PROs. The NNT for subjects to report changes ≥MCID in up to five PROs was two to three, and five for all six PROs (pain, PtGA, physical function, fatigue and short-form 36-item Physical and Mental Component Summary Scores). More patients with improvements ≥MCID in pain at week 6 than those at week 12 had lower disease activity at week 24. Week 12 pain responders had better clinical outcomes at week 24 than non-responders.
Conclusions
The data demonstrate that CZP provides broad relief from the burden of RA.
Trial registration number
NCT00160602.
doi:10.1136/ard.2010.143586
PMCID: PMC3086050  PMID: 21415050
8.  Treatment of active lupus nephritis with the novel immunosuppressant 15-deoxyspergualin: an open-label dose escalation study 
Introduction
As the immunosuppressive potency of 15-deoxyspergualin (DSG) has been shown in the therapy of renal transplant rejection and Wegener's granulomatosis, the intention of this study was to evaluate the safety of DSG in the therapy of lupus nephritis (LN).
Methods
Patients with histologically proven active LN after prior treatment with at least one immunosuppressant were treated with 0.5 mg/kg normal body weight/day DSG, injected subcutaneously for 14 days, followed by a break of one week. These cycles were repeated to a maximum of nine times. Doses of oral corticosteroids were gradually reduced to 7.5 mg/day or lower by cycle 4. Response was measured according to a predefined decision pattern. The dose of DSG was adjusted depending on the efficacy and side effects.
Results
A total of 21 patients were included in this phase-I/II study. After the first DSG injection, one patient was excluded from the study due to renal failure. Five patients dropped out due to adverse events or serious adverse events including fever, leukopenia, oral candidiasis, herpes zoster or pneumonia. Eleven out of 20 patients achieved partial (4) or complete responses (7), 8 were judged as treatment failures and 1 patient was not assessable. Twelve patients completed all nine cycles; in those patients, proteinuria decreased from 5.88 g/day to 3.37 g/day (P = 0.028), Selena-SLEDAI (Safety of Estrogens in Lupus Erythematosus - National Assessment - systemic lupus erythematosus disease activity index) decreased from 17.6 to 11.7. In 13 out of 20 patients, proteinuria decreased by at least 50%; in 7 patients to less than 1 g/day.
Conclusions
Although the number of patients was small, we could demonstrate that DSG provides a tolerably safe treatment for LN. The improvement in proteinuria encourages larger controlled trials.
Trial registration
ClinicalTrials.gov: NCT00709722
doi:10.1186/ar3268
PMCID: PMC3132014  PMID: 21356124
9.  Diagnostic value and clinical laboratory associations of antibodies against recombinant ribosomal P0, P1 and P2 proteins and their native heterocomplex in a Caucasian cohort with systemic lupus erythematosus 
Introduction
In this study, we sought to determine the diagnostic value and clinical laboratory associations of autoantibodies against recombinant ribosomal P0, P1 and P2 proteins and their native heterocomplex in systemic lupus erythematosus (SLE).
Methods
Autoantibodies against recombinant ribosomal P proteins (aRibPR0, aRibPR1 and aRibPR2) and antibodies against native ribosomal P heterocomplex (aRibPNH) were determined in sera from patients with SLE (n = 163), systemic sclerosis (n = 66), Sjögren's syndrome (n = 54), rheumatoid arthritis (n = 90) and healthy donors (n = 100) using enzyme-linked immunosorbent assay. Test results were correlated to medical records, including the American College of Rheumatology criteria, the Systemic Lupus Erythematosus Disease Activity Index 2000, laboratory data and medications of all SLE patients.
Results
Sensitivities of 22.0% for aRibPR0, 14.9% for aRibPR2, 14.3% for aRibPNH and 10.7% for aRibPR1 were obtained at a specificity of 99%. The assay for aRibPR0 detection demonstrated the best performance in receiver-operating characteristics analysis, with aRibPR0 detectable in 10% of anti-Smith antibody and anti-double-stranded DNA-negative sera at a specificity of 100%. ARibPR0 positivity was associated with lymphocytopenia. ARibPR1+ patients had significantly higher γ-glutamyl transpeptidase (GGT) levels than their aRibPR1- counterparts. No specific damage occurred in aRibP+ lupus patients compared with a group of age-, sex- and nephritis-matched aRibP- lupus patients within 3 years.
Conclusions
The determination of antibodies against ribosomal P proteins improves the diagnosis of SLE and should therefore be implemented in upcoming criteria for the diagnosis or classification of SLE. High titers of aRibPR0 can be associated with lymphocytopenia, and high titers of aRibPR1 can be associated with elevated GGT levels. So far, there is no evidence for a prognostic value of aRibPs for damage.
doi:10.1186/ar3244
PMCID: PMC3241364  PMID: 21310064
10.  Anti-dsDNA-NcX ELISA: dsDNA-loaded nucleosomes improve diagnosis and monitoring of disease activity in systemic lupus erythematosus 
Introduction
The objective of this study was to compare the clinical usefulness of the new anti-double-stranded DNA nucleosome-complexed enzyme-linked immunosorbent assay (Anti-dsDNA-NcX ELISA), which is based on dsDNA-loaded nucleosomes as antigens, with established test systems based on dsDNA or nucleosomes alone for systemic lupus erythematosus (SLE) diagnostics and determination of disease activity.
Methods
Sera from a cohort of 964 individuals comprising 207 SLE patients, 357 disease controls and 400 healthy donors were investigated using the Anti-dsDNA-NcX ELISA, Farr assay, Anti-dsDNA ELISA, Anti-nucleosome ELISA and Crithidia luciliae immunofluorescence (CLIF) assay, all of which are tests available from EUROIMMUN Medizinische Labordiagnostika AG (Lübeck, Germany). Receiver operating characteristic curve analyses were performed to compare the sensitivity and specificity of each assay. The test results yielded by these assays in a group of 165 fully characterized SLE patients were compared with the corresponding medical records.
Results
The Anti-dsDNA-NcX ELISA was found to have a sensitivity of 60.9% and a specificity of 98.9% in all 964 individuals at the manufacturer's cutoff of 100 U/ml. At a comparable specificity of 99%, the sensitivity amounted to 59.9% for the Anti-dsDNA-NcX ELISA, 54.1% for the Farr assay, 53.6% for the antinucleosome ELISA and 35.8% for the anti-dsDNA ELISA. The CLIF assay had a sensitivity of 28.0% and a specificity of 98.2%. The Anti-dsDNA-NcX ELISA correlated mostly with global disease activity in a cross-sectional analysis. In a longitudinal analysis of 20 patients with 69 patient visits, changes in Anti-dsDNA-NcX ELISA and antinucleosome ELISA results correlated highly with changes in disease activity over time.
Conclusions
The use of dsDNA-complexed nucleosomes as antigens in ELISA leads to optimized determination of diagnosis and disease activity in SLE patients and is available for clinical practice.
doi:10.1186/ar3250
PMCID: PMC3241370  PMID: 21329504
11.  Clinical and serological evaluation of a novel CENP-A peptide based ELISA 
Introduction
Anti-centromere antibodies (ACA) are useful biomarkers in the diagnosis of systemic sclerosis (SSc). ACA are found in 20 to 40% of SSc patients and, albeit with lower prevalence, in patients with other systemic autoimmune rheumatic diseases. Historically, ACA were detected by indirect immunofluorescence (IIF) on HEp-2 cells and confirmed by immunoassays using recombinant CENP-B. The objective of this study was to evaluate a novel CENP-A peptide ELISA.
Methods
Sera collected from SSc patients (n = 334) and various other diseases (n = 619) and from healthy controls (n = 175) were tested for anti-CENP-A antibodies by the novel CENP-A enzyme linked immunosorbent assay (ELISA). Furthermore, ACA were determined in the disease cohorts by IIF (ImmunoConcepts, Sacramento, CA, USA), CENP-B ELISA (Dr. Fooke), EliA® CENP (Phadia, Freiburg, Germany) and line-immunoassay (LIA, Mikrogen, Neuried, Germany). Serological and clinical associations of anti-CENP-A with other autoantibodies were conducted in one participating centre. Inhibition experiments with either the CENP-A peptide or recombinant CENP-B were carried out to analyse the specificity of anti-CENP-A and -B antibodies.
Results
The CENP-A ELISA results were in good agreement with other ACA detection methods. According to the kappa method, the qualitative agreements were: 0.73 (vs. IIF), 0.81 (vs. LIA), 0.86 (vs. CENP-B ELISA) and 0.97 (vs. EliA® CENP). The quantitative comparison between CENP-A and CENP-B ELISA using 265 samples revealed a correlation value of rho = 0.5 (by Spearman equation). The receiver operating characteristic analysis indicated that the discrimination between SSc patients (n = 131) and various controls (n = 134) was significantly better using the CENP-A as compared to CENP-B ELISA (P < 0.0001). Modified Rodnan skin score was significantly lower in the CENP-A negative group compared to the positive patients (P = 0.013). Inhibition experiments revealed no significant cross reactivity of anti-CENP-A and anti-CENP-B antibodies. Statistically relevant differences for gender ratio (P = 0.0103), specific joint involvement (Jaccoud) (P = 0.0006) and anti-phospholipid syndrome (P = 0.0157) between ACA positive SLE patients and the entire SLE cohort were observed.
Conclusions
Anti-CENP-A antibodies as determined by peptide ELISA represent a sensitive, specific and independent marker for the detection of ACA and are useful biomarkers for the diagnosis of SSc. Our data suggest that anti-CENP-A antibodies are a more specific biomarker for SSc than antibodies to CENP-B. Furthers studies are required to verify these findings.
doi:10.1186/ar3029
PMCID: PMC2911886  PMID: 20487535
12.  Biomarkers as tools for improved diagnostic and therapeutic monitoring in systemic lupus erythematosis 
One of the major challenges in rheumatology is to overcome the classification criteria that previously defined systemic lupus erythematosis, since the heterogeneity of the disease(s) appears to represent a complexity that probably substantially contributed to the failure of a number of recent trials. For those engaged in clinical trials, validated disease activity biomarkers that respond rapidly to treatment and are predictive of clinical response would greatly facilitate early decision-making around futility and dose selection. Likewise, use of validated patient stratification biomarkers possibly in conjunction with autoantibody profiles and disease manifestations will result in the recruitment of more homogeneous patient populations during later stage clinical studies, thereby decreasing size, costs, and risks in pivotal studies.
doi:10.1186/ar2834
PMCID: PMC3003542  PMID: 19939293
13.  Diagnostic value of anti-topoisomerase I antibodies in a large monocentric cohort 
Introduction
In the present study, the detection of anti-topoisomerase I (anti-topo I) autoantibodies was evaluated for diagnosis and risk assessment of systemic sclerosis (SSc) patients in a well characterized large monocentric cohort.
Methods
Sera from patients with SSc (diffuse n = 96, limited n = 113), from patients with overlap syndromes (n = 51), from patients with other diseases associated with SSc (n = 20), as well as from disease controls (n = 487) were analysed for the presence of anti-topo I antibodies by line immunoblot assay and ELISA. Assessment of organ manifestations was performed as proposed by the European Scleroderma Trial and Research network.
Results
The applied test systems for the detection of anti-topo I antibodies revealed a diagnostic sensitivity for SSc of approximately 24% and a diagnostic specificity of at least 99.6%. The sensitivity to identify patients with diffuse SSc amounted to 60%. Patients with anti-topo I antibodies showed a higher burden of skin and lung fibrosis, contractures, electrocardiogram changes, as well as digital ulcers and had more active disease than antibody-negative patients. Signal strengths correlated only weakly with disease activity, with modified Rodnan skin score, with predicted forced vital capacity, and with predicted diffusion capacity levels (P = 0.01, ρ = 0.234, ρ = 0.413, ρ = -0.215, ρ = -0.219). High signal intensities were associated with an increased mortality in diffuse SSc patients (P = 0.003).
Conclusions
Diagnosis and risk assessment of SSc patients can be supported by the detection of anti-topo I antibodies. Signal intensities as obtained by line immunoblot assay or ELISA can be used as a surrogate marker for fibrosis, active disease and worse prognosis.
doi:10.1186/ar2622
PMCID: PMC2688262  PMID: 19232127
14.  Antibodies against PM/Scl-75 and PM/Scl-100 are independent markers for different subsets of systemic sclerosis patients 
Introduction
Anti-PM/Scl antibodies are present in sera from patients with polymyositis (PM), systemic sclerosis (SSc), and PM/SSc overlap syndromes. The prevalence of antibodies against the 75- and 100-kDa PM/Scl proteins and their clinical associations have not been studied in SSc patients in detail so far but could provide a valuable tool for risk assessment in these patients. Furthermore, it remains speculative whether commercially available test systems detecting only anti-PM/Scl-100 antibodies are sufficient in SSc patients.
Methods
Two hundred eighty sera from SSc patients, patients with other connective tissue diseases (n = 209), and healthy blood donors (n = 50) were analyzed for the presence of anti-PM/Scl-75 and anti-PM/Scl-100 antibodies by means of line immunoblot assay. For the SSc patients, possible associations between both subsets of anti-PM/Scl antibodies with clinical and laboratory findings were studied.
Results
The determination of anti-PM/Scl reactivity revealed a diagnostic sensitivity of 12.5% and a specificity of 96.9% for SSc. Among anti-PM/Scl-positive SSc patients, 10.4% and 7.1% were positive for anti-PM/Scl-75 and anti-PM/Scl-100 antibodies, respectively. The highest prevalences of reactivity to PM/Scl were detected in diffuse SSc (19.8%) and overlap syndromes (17.6%). Patients with diffuse SSc showed mainly an anti-PM/Scl-75 response, whereas most cases of overlap syndromes were characterized by reactivity to both PM/Scl antigens. The presence of anti-PM/Scl-75/100 antibodies was associated with muscular and lung involvements as well as with digital ulcers; pulmonary arterial hypertension was found less frequently. Anti-PM/Scl-75 antibodies were detected more frequently in younger and more active patients with joint contractures. Anti-PM/Scl-100 antibodies were associated with creatine kinase elevation; however, gastrointestinal involvements were observed less frequently.
Conclusions
Anti-PM/Scl antibodies are common in distinct SSc subsets and are associated with several clinical symptoms. They are directed mainly to the PM/Scl-75 antigen. Consequently, the detection of anti-PM/Scl antibodies by tests based only on PM/Scl-100 as an antigen source may miss a relevant number of SSc patients positive for these antibodies.
doi:10.1186/ar2614
PMCID: PMC2688254  PMID: 19220911
15.  Developments in lupus 2006 
Published reports in 2006 on systemic lupus erythematosus are reviewed with regard to preclinical and clinical studies on disturbances of the immune system including co-stimulation, cytokines and recent insights into new therapeutic approaches. Increasing knowledge of components of the innate immune system, such as certain receptors (Toll-like receptors, Fc receptors and complement receptors) and cytokines as well as immune cells (dendritic cells, plasmacytoid cells and neutrophils) supports their immunopathogenic relevance and enhance our understanding of the pathogenic complexity of lupus. Although it remains to be shown which of those could be targets for therapy or biomarkers, lymphocyte-directed therapy is currently under promising clinical investigation.
doi:10.1186/ar2183
PMCID: PMC2206361  PMID: 17634152
16.  International Multicenter Evaluation of Autoantibodies to Ribosomal P Proteins 
Autoantibodies to the ribosomal phosphoproteins (Rib-P) are a serological feature of patients with systemic lupus erythematosus (SLE). The reported prevalence of anti-Rib-P antibodies in SLE ranges from 10 to 40%, being higher in Asian patients. The variation in the observed frequency may be related to a number of factors but is dependent in large part on the test system used to detect the autoantibodies. An association of anti-Rib-P with central nervous system involvement and neuropsychiatric manifestations of SLE has been controversial. In the present international multicenter study, we evaluated the clinical accuracy of a new sensitive Rib-P-specific enzyme-linked immunosorbent assay based on recombinant Rib-P polypeptides. The results showed that 21.3% of 947 SLE patients, but only 0.7% of 1,113 control patients, had a positive test result (P < 0.0001). The sensitivity, specificity, positive and negative predictive values, and diagnostic efficiency were determined to be 21.3%, 99.3%, 95.6%, 62.2%, and 65.3%, respectively. When evaluated in the context of participating centers, the prevalence of anti-Rib-P antibodies was found in descending frequency, as follows: China (35%) > Poland (34%) > Japan (28%) > United States (26%) > Germany (Freiburg; 23.3%) > Denmark (20.5%) > Germany (Berlin; 19%) > Mexico (15.7%) > Israel (11.7%) > Brazil (10%) > Canada (8%). The substantial data from this study indicate that the prevalence of anti-Rib-P antibodies may not be restricted to the genetic background of the patients or to the detection system but may depend on regional practice differences and patient selection. We confirm previously reported associations of antiribosomal antibodies with clinical symptoms and serological findings. Remarkably, we found a lower occurrence of serositis in Rib-P-positive lupus patients.
doi:10.1128/CVI.13.1.77-83.2006
PMCID: PMC1356623  PMID: 16426003
17.  Short-lived Plasmablasts and Long-lived Plasma Cells Contribute to Chronic Humoral Autoimmunity in NZB/W Mice 
The Journal of Experimental Medicine  2004;199(11):1577-1584.
The current view holds that chronic autoimmune diseases are driven by the continuous activation of autoreactive B and T lymphocytes. However, despite the use of potent immunosuppressive drugs designed to interfere with this activation the production of autoantibodies often persists and contributes to progression of the immunopathology. In the present study, we analyzed the life span of (auto)antibody-secreting cells in the spleens of NZB × NZW F1 (NZB/W) mice, a murine model of systemic lupus erythematosus. The number of splenic ASCs increased in mice aged 1–5 mo and became stable thereafter. Less than 60% of the splenic (auto)antibody-secreting cells were short-lived plasmablasts, whereas 40% were nondividing, long-lived plasma cells with a half-life of >6 mo. In NZB/W mice and D42 Ig heavy chain knock-in mice, a fraction of DNA-specific plasma cells were also long-lived. Although antiproliferative immunosuppressive therapy depleted short-lived plasmablasts, long-lived plasma cells survived and continued to produce (auto)antibodies. Thus, long-lived, autoreactive plasma cells are a relevant target for researchers aiming to develop curative therapies for autoimmune diseases.
doi:10.1084/jem.20040168
PMCID: PMC2211779  PMID: 15173206
plasma cell; autoimmunity; SLE; antibodies; anti-DNA
18.  Autologous stem-cell transplantation in refractory autoimmune diseases after in vivo immunoablation and ex vivo depletion of mononuclear cells 
Arthritis Research  2000;2(4):327-336.
Autoimmune diseases that are resistant to conventional treatment cause severe morbidity and even mortality. In the present study we demonstrate that complete remissions can be achieved in refractory polychondritis and systemic lupus erythematosus (SLE), even at advanced stage, with the use of autologous stem-cell transplantation (SCT). Remissions persisted after reconstitution of the immune system. In the treatment of advanced systemic sclerosis (SSc), stable disease may be achieved with autologous SCT.
Introduction:
Patients with persistently active autoimmune diseases are considered to be candidates for autologous SCT. We performed a phase 1/2 study in a limited number of patients who were refractory to conventional immunosuppressive treatment. Following a period of uncontrolled disease activity for at least 6 months, autologous SCT was performed, after in vivo immunoablation and ex vivo depletion of mononuclear cells.
Aims:
To investigate feasibility, toxicity and efficacy of the treatment, and the incidence of emergent infections.
Methods:
Seven patients (aged between 23 and 48 years) were included in the single-centre trial: one had relapsing polychondritis, three had treatment-refractory SLE and three patients had SSc. Stem-cell mobilization was achieved by treatment with moderate-dose cyclophosphamide (2 g/m2; in terms of myelotoxic side effects or myelosuppression) and granulocyte colony-stimulating factor (G-CSF). CD34- cells of the leukapheresis products were removed by high-gradient magnetic cell sorting. After stem-cell collection, immunoablation was performed with high-dose cyclophosphamide (200 mg/kg body weight) and antithymocyte globulin (ATG; 90 mg/kg body weight). Autologous SCT was followed by reconstitution of the immune system, which was monitored by six-parameter flow cytometry and standard serology. The trial fulfilled the European League Against Rheumatism (EULAR) and the European Group for Blood and Marrow Transplantation (EBMT) guidelines for blood and bone marrow stem-cell transplants in autoimmune disease.
Results:
Among the seven patients studied, the patient with relapsing polychondritis and the patients with SLE were successfully treated and remained in complete remission during a follow up of 10-21 months. Remission persisted despite reconstitution of the immune system, resulting in high numbers of effector-/memory-type T-helper lymphocytes and increasing populations in the naïve T-cell compartment. Before autologous SCT, one of the patients with SLE had a long-lasting secondary antiphospholipid syndrome, with high anticardiolipin antibodies and thromboembolic events. After autologous SCT the antiphospholipid antibodies became negative, and no thrombosis occurred during follow up. Two of the patients with SSc were unaffected by treatment with autologous SCT for 6 or 13 months. The other patient with SSc died 2 days after autologous SCT because of cardiac failure.
During stem-cell mobilization with G-CSF, flares of autoimmune disease were seen in the patient with polychondritis and in one patient with SLE. The strategy utilized for depletion of CD34- cells led to a reduction by 4.5-5 log of contaminating CD3+ cells in the transplant. T-cell add-back was required in the patient with polychondritis and in one patient with SLE to provide a dose of 1×104 CD3+ cells/kg body weight for the transplant.
Discussion:
In vivo immunoablation in combination with autologous SCT after ex vivo depletion of CD34- cells can block the autoimmune process in relapsing polychondritis or SLE without incidence of severe infections. The remissions were achieved in patients with advanced disease that was refractory to previous intensive immunosuppressive therapy. The present results do not indicate that large-scale contamination of the stem-cell transplant with autoreactive cells after selection for CD34+cells occurred. After the preparative regimen, the application of G-CSF was avoided, because induction of flares of the autoimmune disease were noticed during the mobilization of stem cells. In SSc patients, distinct remissions were not observable after autologous SCT; the serological and clinical status did not improve. Follow-up periods of more than 12 months may be required to identify successful treatment with autologous SCT in SSc patients. Among the various autoimmune diseases the efficacy of autologous SCT appears to be dependent on the underlying pathophysiology. The results of the present phase 1/2 study suggest that patients with advanced stage SSc should not be treated with autologous SCT, until the reasons for the lack of response and the possible mortality due to cardiac complications are identified. The observation of flares of autoimmune disease after application of G-CSF emphasizes the need for critical evaluation of the role of G-CSF in immunoablative regimens.
PMCID: PMC17815  PMID: 11056673
autologous stem-cell transplantation; polychondritis; refractory autoimmune disease; systemic lupus erythematosus; systemic sclerosis

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