Serum anti-dsDNA Antibody Research Articles

AB0499 Changes in the Relationship between Baff, BAFF-R and B Cell Phenotype following Treatment with Rituximab in Patients with Systemic Lupus Erythematosus

BackgroundIn vitro, the key B-cell cytokine BAFF (B-lymphocyte activating factor) differentially promotes the survival of transitional B-cells and plasmablasts through interaction with specific receptors. Following rituximab (RTX) therapy in patients...

THU0049 Uc-Mscs Inhibit Both T Cell Apoptosis and Autophagy in Patients with Systemic Lupus Erythematosus

BackgroundT cells from SLE patients have higher spontaneous apoptotic rate than that from healthy donors. The appearance of nucleosomes from these apoptotic cells in circulation may induce the production of...

Pathogenetic role of an autoimmune susceptibility locus derived from MRL/MpJ strain chromosome 1 in chronic pancreas inflammation

We examined the role of Mag, an autoimmune susceptibility locus encoded by the telomeric region of MRL/MpJ mouse chromosome 1, in the pathogenesis of autoimmune exocrinopathy. At nine to 12 months of age, strain-specific differences were observed in the pancreas of the animals. B- and T-cell-containing periductal/perivascular cell infiltrations in the pancreases of MRL/MpJ and B6.MRLc1 congenic C57BL/6-background Mag-carrying strains were more severe than were those of C57BL/6. Pancreatic periductal/perivascular cell infiltration was observed frequently in A/J, AKR/N, B6.MRLc1, C57BL/6, and MRL/MpJ, moderately in DBA/1 and DBA/2, and rarely in BALB/c and C3H/He strains. Females tended to have greater pancreatic periductal/perivascular cell infiltration than males. C57BL/6 mice possessed defined borders between cell infiltrations and acini, but borders were indistinct in MRL/MpJ and B6.MRLc1 mice. We attributed this to the invasion of inflammatory cells between each acinus and the disruption of acinar cells around cell infiltrations in the latter strains. No strain-specific differences were observed in the appearance of fibrotic lesions and high endothelial venules in the cell infiltrates. The levels of serum anti-dsDNA antibodies and amylase, and mRNA expression of tumor necrosis factor-α and Fc gamma receptor III (encoded on Mag) in the pancreases, were elevated in MRL/MpJ- and B6.MRLc1-strain mice relative to C57BL/6. These results emphasized the crucial roles of Mag in the molecular and genetic pathogenesis of autoimmune-mediated pancreatitis.

Antibody against chromatin assembly factor-1 is a novel autoantibody specifically recognized in systemic lupus erythematosus.

Autoantibodies to proliferating cell nuclear antigen (PCNA) are specifically, if rarely, present in systemic lupus erythematosus (SLE) patient sera. Even SLE patients lacking PCNA reactivity often show reaction to PCNA-binding protein. Here, immunoreactivity to chromatin assembly factor-1 (CAF-1), an essential molecule for DNA replication and a PCNA-binding protein, was compared for the sera of SLE patients, normal healthy controls (NHCs) and other disease controls, and in autoimmune sera reactive to standard autoantigens, by enzyme-linked immunosorbent assay (ELISA), indirect immunofluorescence, and immunoblotting. CAF1 and IRF1 expression in SLE and NHC peripheral mononuclear cells were compared by quantitative real-time polymerase chain reaction. Serum interferon-γ-inducing protein-10 and anti-double-stranded (ds)DNA antibody levels were measured by ELISA. Increased CAF-1 autoimmune reactivity was recognized in SLE or serum anti-dsDNA antibody-positive patients. Significantly greater central nervous system (CNS) involvement (aseptic meningitis) and serum anti-dsDNA antibody titers were present more often in anti-CAF-1 antibody-positive than antibody-negative SLE patients. IFN-γ positively regulated CAF-1 expression invitro and was associated with anti-CAF-1 antibody production in SLE. Thus, a novel anti-CAF-1 autoantibody is frequently found in patients with SLE and is a useful biomarker for diagnosis, especially in cases with CNS involvement. Aberrant IFN-γ regulation appears to play an important role in anti-CAF-1 antibody production in SLE.

Detection of dynamic frequencies of Th17 cells and their associations with clinical parameters in patients with systemic lupus erythematosus receiving standard therapy.

Recent evidence implicated an important role of Th17 cells in the pathogenesis of systemic lupus erythematosus (SLE). However, the association between dynamic changes of Th17 cell frequency and clinical parameters in SLE patients receiving clinical managements remains unknown. Here, we sought to evaluate their correlation in Chinese new-onset SLE patients with standard therapy. We found that the frequency of Th17 cells was higher in SLE patients than that in healthy controls and could be decreased by standard care. In consistent, the level of serum IL-6, IL-1β, IL-23, and Stat3 activity was elevated in SLE patients and down-regulated by disease treatment. Of note, the frequency of Th17 cells was correlated with SLEDAI and serum C3 in SLE patients. The changes of Th17 cell frequency were associated with those of SLEDAI and serum C3 in SLE patients between pretreatment and posttreatment. Further, the Th17 cell frequency was positively correlated with serum anti-dsDNA antibody in SLE patients. The changes of Th17 cell frequency were associated with those of serum anti-dsDNA antibody in SLE patients. Our findings showed that dynamic frequencies of Th17 cells were closely correlated with clinical parameters in SLE patients receiving standard treatment, which could facilitate the efficient management and development of novel therapeutics for SLE.

Endogenous IL-17A promotes pristane-induced systemic autoimmunity and experimental lupus nephritis (BA4P.218)

Abstract IL-17A is increased in serum and in kidney biopsies from patients with lupus nephritis, but direct evidence of pathogenicity is less well established. These studies sought to define the role of IL-17A in experimental lupus induced by the administration of pristane to WT and IL-17A-/- mice. Local and systemic immune responses were assessed after 6 days and 8 weeks, and autoimmunity, glomerular inflammation and renal injury were determined at 7 months. Peritoneal IL-17A production increased significantly 6 days after pristane injection, with innate cells (neutrophils and macrophages) being the predominant source of IL-17A. After 8 weeks, while systemic IL-17A was still readily detected in WT mice, IFN-γ and TNF were diminished in IL-17A-/- mice. Seven months after pristane, humoral autoimmunity was diminished in IL-17A-/- mice, with decreased serum lgG and anti-dsDNA antibody titers. Renal inflammation and injury was less in the absence of IL-17A. Compared to WT mice, glomerular IgG, complement deposition, glomerular CD4+ T cells and intrarenal pro-inflammatory mediator expression were decreased in IL-17A-/- mice. WT mice developed progressive albuminuria, but albuminuria (7 months: WT 271±56, IL-17A 88±16μg/day; P<0.05) and histological abnormalities were attenuated in IL-17A-/- mice. Therefore, IL-17A is required for the full development of systemic autoimmunity and experimental lupus nephritis. Early in the development of autoimmunity, innate immune cells produce IL-17A.

A8.13 Changes in the relationship between BAFF, BAFF-R and B cell phenotype following rituximab in patients with systemic lupus erythematosus

Background and AimsIn vitro, BAFF (B-lymphocyte activating factor) differentially promotes the survival of B-cells and plasmablasts through receptors for the key B-cell cytokine BAFF. Following rituximab (RTX) therapy in patients...

Close Relations between Podocyte Injuries and Membranous Proliferative Glomerulonephritis in Autoimmune Murine Models

Background: Membranous proliferative glomerulonephritis (MPGN) is a major primary cause of chronic kidney disease (CKD). Podocyte injury is crucial in the pathogenesis of glomerular disease with proteinuria, leading to CKD. To assess podocyte injuries in MPGN, the pathological features of spontaneous murine models were analyzed. Methods: The autoimmune-prone mice strains BXSB/MpJ-Yaa and B6.MRL-(D1Mit202-D1Mit403) were used as the MPGN models, and BXSB/MpJ-Yaa⁺ and C57BL/6 were used as the respective controls. In addition to clinical parameters and glomerular histopathology, the protein and mRNA levels of podocyte functional markers were evaluated as indices for podocyte injuries. The relation between MPGN pathology and podocyte injuries was analyzed by statistical correlation. Results: Both models developed MPGN with albuminuria and elevated serum anti-double-strand DNA (dsDNA) antibody levels. BXSB/MpJ-Yaa and B6.MRL showed severe proliferative lesions with T and B cell infiltrations and membranous lesions with T cell infiltrations, respectively. Foot process effacement and microvillus-like structure formation were observed ultrastructurally in the podocytes of both MPGN models. Furthermore, both MPGN models showed a decrease in immune-positive areas of nephrin, podocin and synaptopodin in the glomerulus, and in the mRNA expression of Nphs1, Nphs2, Synpo, Actn4, Cd2ap, and Podxl in the isolated glomerulus. Significant negative correlations were detected between serum anti-dsDNA antibody levels and glomerular Nphs1 expression, and between urinary albumin-to-creatinine ratio and glomerular expression of Nphs1, Synpo, Actn4, Cd2ap, or Podxl.Conclusion: MPGN models clearly developed podocyte injuries characterized by the decreased expression of podocyte functional markers with altered morphology. These data emphasized the importance of regulation of podocyte injuries in MPGN.

Long-Term Tacrolimus-Based Immunosuppressive Treatment for Young Patients with Lupus Nephritis: A Prospective Study in Daily Clinical Practice

Background: The optimal long-term treatment for lupus nephritis (LN) in pubertal patients remains to be determined. Tacrolimus (Tac) inhibits T cell activation, and is therefore expected to be effective in patients with LN. However, little has been published about the long-term efficacy and safety of Tac-based immunosuppressive treatment of young patients with LN in daily clinical practice. Methods: Nineteen consecutive patients with biopsy-proven LN were recruited for an open-label, prospective, long-term Tac-based treatment regimen. Tac was administered once daily at a dose of 3 mg as induction- or reinduction-maintenance treatment. Four patients (21%) with new-onset LN received mizoribine at a dose of 150 mg once daily in addition to Tac. Treatment outcomes were defined by the European Consensus Lupus Activity Measurement (ECLAM) index, urinary protein/creatinine ratio (Up/cr), serum creatinine and serological lupus markers (complement C3, complement hemolytic activity, CH₅₀, and anti-dsDNA antibody titer). Data on these parameters were collected prospectively. The median follow-up was 42 months. Results: Baseline characteristics of the patients were as follows: mean age, 18 years; Up/cr, 0.89 ± 1.17; serum C3, 68.1 ± 23.2 mg/dl (normal, 79–152 mg/dl); serum CH₅₀, 26.4 ± 10.5 U/ml (normal, 23–46 U/ml); serum anti-dsDNA antibody titer, 69.3 ± 67.5 IU/ml (normal, <12.0 IU/ml); serum creatinine, 0.55 ± 0.18 mg/dl, and ECLAM index, 4.6 ± 1.9. Despite gradually tapering the dose of concomitantly administered prednisolone, a marked improvement compared with baseline values was observed in all outcome measures as early as 3 months after the initiation of treatment, and the favorable changes persisted throughout the treatment period in most of the patients. Sustained improvements in the outcome measures compared with the baseline values were confirmed after a mean of 42 months of treatment: ECLAM index, 1.1 ± 1.1; serum CH₅₀, 36.0 ± 12.8 U/ml, anti-dsDNA antibody titer, 22.5 ± 26.5 IU/ml (all p < 0.01); Up/cr ratio, 0.35 ± 0.58, and serum C3 level, 79.7 ± 17.6 mg/dl (both p < 0.05). Serum creatinine level remained within the normal range in all the study participants. Complete response was achieved in 12 patients (63%), and a partial response was achieved in 5 patients (26%). The remaining 2 patients showed no response. No serious adverse effects were observed. Conclusion: The data suggest that long-term, relatively low-dose Tac-based immunosuppressive treatment is beneficial and has low cytotoxicity, and therefore represents an attractive option for the treatment of young patients with LN in daily clinical practice. Further studies involving a larger number of patients are needed to confirm these results.

A Case of ANA-negative, Anti-dsDNA Negative, and Anti-Ro/SSA Positive Membranous Lupus Nephropathy

Systemic lupus erythematosus (SLE) is an autoimmune disease characterized by the production of diverse autoantibodies with various systemic organ involvements. In patients with SLE, autoantibodies, such as antinuclear antibody (ANA) and anti-dsDNA antibody, play an important role not only in diagnosing the disease, but also representing the pathogenesis of the disease. ANA is the main screening tool in diagnosis and serum complement levels and anti-dsDNA antibody level are closely related to the disease activities. Nevertheless, exceptionally, some patients represent with negative ANA and/or anti-dsDNA antibody leading to difficulties in diagnosing the disease. Here, we report a case of 37-year old female SLE patient with negative ANA, negative anti-dsDNA antibody, and positive anti-Ro/SSA antibody, which manifested with nephrotic syndrome.

Detection of Antinuclear Antibodies (ANA), Antibodies to Double Stranded DNA (Anti-Dsdna) and Antibodies to Extractable Nuclear Antigens (Anti-ENA) in Greek Patients

The diagnosis of autoimmune diseases depends on clinical history, physical examination, and laboratory detection of specific autoantibodies directed against nuclear or cytoplasmic antigens. The aim of this study was to investigate the types and prevalence of serum ANA, anti-dsDNA, and anti-ENA antibodies in a population examined at the Immunology Laboratory of the Naval Hospital of Athens and their correlation with patient age and gender. We evaluated the sera of 3000 patients, both male and female, aged between 18 and 75 years old, born in different parts of Greece. All requests for ANA detection were performed by enzyme linked immunoassay (ELI SA). All ELISA borderline, weak positive and pbsitive results were run on the indirect immunofluorescence assay (IFA) on Hep-2 cells. Anti-dsDNA antibodies were detected by IFA on Crithidia luciliae substrate slides. Antibodies to Sm, RNP, SS-A(Ro), SS-B(La), Jo-1, and Scl-70 were determined by an immunodot qualitative test. 206 patients were positive for ANA, representing a prevalence of 6.87%. The positive samples demonstrated the expected variety of titers and reactivity patterns. 9 samples (4.37%) presented anti-dsDNA positive result and 44 (21.36%) presented reactivity to various ENA autoantibodies. All the examined autoantibodies presented a higher prevalence among women. In this study we estimated the prevalence of ANA, anti-dsDNA, and anti-ENA antibodies in samples of 3000 sera. We followed the strategy of performing immunofluorescence testing in order to confirm positive ELISA results, proposed by many scientists. We also evaluated autoantibody titers and fluorescence patterns, and we examined the correlation of autoantibody presence with patient age and gender.

Blimp-1 siRNA inhibits B cell differentiation and prevents the development of lupus in mice

Cumulative evidence suggest that B-lymphocytes play a role in the development of systemic lupus erythematosus (SLE). Thus, the therapeutic approach targeting specific B cells provides a promising way to treat SLE. Blimp-1 (B lymphocyte induced maturation protein), a transcriptional factor, controls the terminal differentiation of mature B cells to plasma cells. To explore the potential of Blimp-1 in the SLE development, we constructed the adenovirus encoding Blimp-1 siRNA, and injected it into BWF1 lupus mice. The results demonstrated that Blimp-1 siRNA decreased the Blimp-1 expression of B cells by regulating XBP-1 (X Box binding protein-1), BCMA (B-cell maturation antigen) expression through c-myc pathway. In addition, Blimp-1 siRNA eliminated anti-dsDNA antibody-producing plsma cells, reduced serum anti-dsDNA antibody levels and impeded the development of lupus. Therefore, our data provide the insight into the mechanism of Blimp-1 in SLE development and might represent a promising therapeutic strategy for autoantibody-mediated diseases.

Circulating anti-double-stranded DNA antibody-secreting cells in patients with systemic lupus erythematosus: a novel biomarker for disease activity

Antibodies against double-stranded DNA (dsDNA) are widely used to diagnose systemic lupus erythematosus (SLE) and evaluate its activity in patients. This study was undertaken to examine the clinical utility of circulating anti-dsDNA antibody-secreting cells for evaluating SLE patients. Anti-dsDNA antibody-secreting cells quantified using an enzyme-linked immunospot assay were detected in the spleen, bone marrow and peripheral blood from MRL/lpr but not in control BALB/c mice. Circulating anti-dsDNA antibody-secreting cells were detected in 29 (22%) of 130 patients with SLE, but in none of 49 with non-SLE connective-tissue disease or 18 healthy controls. The presence of circulating anti-dsDNA antibody-secreting cells was associated with persistent proteinuria, high SLE disease activity index and systemic lupus activity measures, and a high serum anti-dsDNA antibody titre measured with an enzyme-linked immunosorbent assay. The positive predictive value for active disease was 48% for circulating anti-dsDNA antibody-secreting cells versus 17% for serum anti-dsDNA antibodies. A prospective cohort of patients with circulating anti-dsDNA antibodies and inactive SLE showed that the cumulative disease flare-free rate was significantly lower in patients with than without circulating anti-dsDNA antibody-secreting cells (p < 0.001). Circulating anti-dsDNA antibody-secreting cells are a useful biomarker for assessing disease activity in SLE patients.

Apolipoprotein E-knockout mice show increased titers of serum anti-nuclear and anti-dsDNA antibodies

Apolipoprotein E-knockout (ApoE−/−) mice, atherosclerosis-prone mice, show an autoimmune response, but the pathogenesis is not fully understood. We investigated the pathogenesis in female and male ApoE−/− mice. The spleens of all ApoE−/− and C57BL/6 (B6) mice were weighed. The serum IgG level and titers of anti-nuclear antibody (ANA) and anti-double-stranded DNA (anti-dsDNA) antibody were assayed by ELISA. Apoptosis of spleen tissue was evaluated by TUNEL. TLR4 level in spleen tissue was tested by immunohistochemistry and Western blot analysis. Levels of MyD88, p38, phosphorylated p38 (pp38), interferon regulatory factor 3 (IRF3) and Bcl-2-associated X protein (Bax) in spleen tissue were detected by Western blot analysis. We also survey the changes of serum autoantibodies, spleen weight, splenocyte apoptosis and the expressions of TLR4, MyD88, pp38, IRF3 and Bax in spleen tissue in male ApoE−/− mice after 4weeks of lipopolysaccharide (LPS), Toll-like receptor 4 ligand, administration. ApoE−/− mice showed splenomegaly and significantly increased serum level of IgG and titers of ANA and anti-dsDNA antibody as compared with B6 mice. Splenocyte apoptosis and the expression of TLR4, MyD88, pp38, IRF3 and Bax in spleen tissue were significantly lower in ApoE−/− than B6 mice. The expression of TLR4, MyD88, IRF3, pp38, and Bax differed by sex in ApoE−/− spleen tissue. The down-regulation of TLR4 signal molecules induced by LPS led to decreased expression of Bax and increased serum titers of ANA and anti-dsDNA antibody. Therefore, the TLR4 signal pathway may participate in maintaining the balance of splenocyte apoptosis and autoantibody production in ApoE−/− mice.

Heat shock protein 90 inhibition by 17-DMAG lessens disease in the MRL/lpr mouse model of systemic lupus erythematosus

Elevated expression of heat shock protein 90 (HSP90) has been found in kidneys and serum of systemic lupus erythematosus (SLE) patients and MRL/Mp-Fas(lpr)/Fas(lpr) (MRL/lpr) autoimmune mice. We investigated if inhibition of HSP90 would reduce disease in MRL/lpr mice. In vitro, pretreatment of mesangial cells with HSP90 inhibitor Geldanamycin prior to immune-stimulation showed reduced expression of IL-6, IL-12 and NO. In vivo, we found HSP90 expression was elevated in MRL/lpr kidneys when compared to C57BL/6 mice and MRL/lpr mice treated with HSP90 inhibitor 17-DMAG. MRL/lpr mice treated with 17-DMAG showed decreased proteinuria and reduced serum anti-dsDNA antibody production. Glomerulonephritis and glomerular IgG and C3 were not significantly affected by administration of 17-DMAG in MRL/lpr. 17-DMAG increased CD8(+) T cells, reduced double-negative T cells, decreased the CD4/CD8 ratio and reduced follicular B cells. These studies suggest that HSP90 may play a role in regulating T-cell differentiation and activation and that HSP90 inhibition may reduce inflammation in lupus.

Increased CD45RA+FoxP3low Regulatory T Cells with Impaired Suppressive Function in Patients with Systemic Lupus Erythematosus

BackgroundThe role of naturally occurring regulatory T cells (Treg) in the control of the development of systemic lupus erythematosus (SLE) has not been well defined. Therefore, we dissect the phenotypically heterogeneous CD4+FoxP3+ T cells into subpopulations during the dynamic SLE development.Methodlogy/Principal FindingsTo evaluate the proliferative and suppressive capacities of different CD4+ T cell subgroups between active SLE patients and healthy donors, we employed CD45RA and CD25 as surface markers and carboxyfluorescein diacetatesuccinimidyl ester (CFSE) dilution assay. In addition, multiplex cytokines expression in active SLE patients was assessed using Luminex assay. Here, we showed a significant increase in the frequency of CD45RA+FoxP3low naive Treg cells (nTreg cells) and CD45RA−FoxP3low (non-Treg) cells in patients with active SLE. In active SLE patients, the increased proportions of CD45RA+FoxP3low nTreg cells were positively correlated with the disease based on SLE disease activity index (SLEDAI) and the status of serum anti-dsDNA antibodies. We found that the surface marker combination of CD25+CD45RA+ can be used to defined CD45RA+FoxP3low nTreg cells for functional assays, wherein nTreg cells from active SLE patients demonstrated defective suppression function. A significant correlation was observed between inflammatory cytokines, such as IL-6, IL-12 and TNFα, and the frequency of nTreg cells. Furthermore, the CD45RA+FoxP3low nTreg cell subset increased when cultured with SLE serum compared to healthy donor serum, suggesting that the elevated inflammatory cytokines of SLE serum may promote nTreg cell proliferation/expansion.Conclusions/SignificanceOur results indicate that impaired numbers of functional CD45RA+FoxP3low naive Treg cell and CD45RA−FoxP3low non-suppressive T cell subsets in inflammatory conditions may contribute to SLE development. Therefore, analysis of subsets of FoxP3+ T cells, using a combination of FoxP3, CD25 and CD45RA, rather than whole FoxP3+ T cells, will help us to better understand the pathogenesis of SLE and may lead to the development of new therapeutic strategies.

Early treatment with rituximab in newly diagnosed systemic lupus erythematosus patients: a steroid-sparing regimen

To assess the effectiveness of B-cell depletion therapy (BCDT) as a steroid-sparing treatment in newly diagnosed SLE patients. Eight female SLE patients were treated with BCDT using a rituximab/CYC-based regimen aiming to avoid the routine use of oral steroids. Post-treatment, patients were given AZA. The BILAG disease activity index was used for clinical assessment. Serum anti-dsDNA, complement (C3), ESR, circulating B lymphocytes (CD19(+)) and protein : creatinine ratio were tested at 0, 1, 3, 6 and 12 months post-treatment. Disease activity and steroid requirement over the first 6 months of treatment were compared with three SLE patients treated conventionally, each carefully matched for ethnicity, sex, age at disease onset and disease duration at diagnosis. All patients achieved B-cell depletion (CD19 count <0.005 × 10(9)/l). The mean decrease in global BILAG at 6 months for the BCDT patients was -12.0 vs 13.22 for the controls. Post-BCDT, no patient developed any significant deterioration, mean ESR fell from 70.12 to 17.14 mm/h at 6 months, mean serum anti-dsDNA antibody levels fell by >70% at 1 month and serum C3 level normalized in two patients by 6 months. There were no adverse events. The mean cumulative prednisolone dose at 6 months for the BCDT patients was 1287.3 mg (range 250-4501.8 mg) vs 2834.6 mg (range 0-6802.5 mg) for the controls. Early treatment of SLE patients with BCDT is safe and effective and enables a reduction in the overall steroid burden.

The dual role of complement in the progression of renal disease in NZB/W F1 mice and alternative pathway inhibition

Complement plays a dual role in the progression of systemic lupus erythematosus since it has important protective functions, such as the clearance of immune complexes and apoptotic cells, but is also a mediator of renal inflammation. To investigate this balance in a clinically relevant setting, we investigated how targeted inhibition of all complement pathways vs. targeted inhibition of only the alternative pathway impacts immune and therapeutic outcomes in NZB/W F1 mice. Following onset of proteinuria, mice were injected twice weekly with CR2-fH (inhibits alternative pathway), CR2-Crry (inhibits all pathways at C3 activation step), sCR2 (C3d targeting vehicle) or saline. Sera were analyzed every 2 weeks for anti-dsDNA antibody levels, and urinary albumin excretion was determined. Kidneys were collected for histological evaluation at 32 weeks. Compared to the control group, all CR2-fH, CR2-Crry and sCR2 treated groups showed significantly reduced serum anti-dsDNA antibody levels and strong trends towards reduced glomerular IgG deposition levels. Glomerular C3 deposition levels were also significantly reduced in all three-treated groups. However, significant reductions of disease activity (albuminuria and glomerulonephritis) were only seen in the CR2-fH treated group. These data highlight the dual role played by complement in the pathogenesis of lupus, and demonstrate a benefit of selectively inhibiting the alternative complement pathway, presumably because of protective contributions from the classical and/or lectin pathways. The sCR2 targeting moiety appears to be contributing to therapeutic outcome via modulation of autoimmunity. Furthermore, these results are largely consistent with our previous data using the MRL/lpr lupus model, thus broadening the significance of these findings.

Antinucleosome antibodies as a potential biomarker for the evaluation of renal pathological activity in patients with proliferative lupus nephritis

The objective of this study is to evaluate the correlation between antinucleosome antibodies and renal pathological activity in patients with proliferative lupus nephritis (LN). We evaluated 36 patients with proliferative LN, 14 non-renal lupus patients and 10 healthy volunteers. Lupus activity was assessed using the British Isles Lupus Assessment Group 2004 (BILAG 2004) index, serum anti-double stranded DNA (anti-dsDNA) levels, serum complement levels and daily urinary protein levels. All 36 lupus nephritis patients received renal biopsy. Antinucleosome antibodies were detected by enzyme-linked immunosorbent assay (ELISA). Our results showed that levels of serum antinucleosome antibodies were significantly higher in LN patients (median 90.35 units/ml, interquartile range [IQR] 37.38-135.23) than in non-renal SLE patients (median 5.45 units/ml, IQR 2.6-28.93, p <0.05) and in healthy volunteers (median 3.35 units/ml, IQR 2.95-5.23, p <0.001). Serum levels of antinucleosome antibodies were positively correlated with BILAG index (Spearman's r = 0.645, p <0.001) and serum anti-dsDNA antibody levels (r(s) = 0.644, p <0.01), while serum levels of antinucleosome antibodies were negatively correlated with serum levels of C3 (r(s) = -0.400, p <0.01) and C4 (r(s) = -0.300, p <0.05). Serum levels of antinucleosome antibodies were positively correlated with the histological activity index of LN (r(s) = 0.368, p <0.05). However, there was no significant correlation between serum levels of antinucleosome antibodies and the histological chronicity index. In conclusion, the serum level of antinucleosome antibodies is a potential biomarker for early recognition of renal involvement and evaluation of disease activity in SLE. Our preliminary results suggested that serum levels of antinucleosome antibodies might be a potential biomarker in evaluating pathological activity of LN.

Effects of water-soluble tacrolimus-PEG conjugate on insulin-dependent diabetes mellitus and systemic lupus erythematosus

The effects of a water-soluble tacrolimus-PEG conjugate (KI-102) on insulin-dependent diabetes mellitus and systemic lupus erythematosus were investigated. KI-102 was stable at pH 4.0-4.5 and 4°C. The area under the concentration-time curve, the time of maximum concentration, and the maximum concentration were 43.4 ng·h/mL, 0.85 h, and 8.1 ng/mL, respectively, similar to those of FK506. Mice that administered KI-102 at 4.32 mg/kg had the plasma glucose concentrations that decreased to 7.5 mmol/L after 170 days, similar to that of mice administered FK506 at 0.6 mg/kg. There were no incidences of diabetes when KI-102 was administered at 86.4 mg/kg after 24 weeks. The group that administered 43.2 mg/kg had decreases in the concentrations of β-hydroxybutyrate (60%), triglyceride (24%), and cholesterol (30%). KI-102 administered at 180 mg/kg reduced serum anti-dsDNA antibody activity by 64% compared with a control. Urinary albumin concentration in the same group decreased 81% compared with the control. These results indicate that KI-102 may be practically applicable as prodrug of FK506.