SERPINB3 delays glomerulonephritis and attenuates the lupus-like disease in lupus murine models by inducing a more tolerogenic immune phenotype

Objective: To explore the effects of SERPINB3 administration in murine lupus models with a focus on lupus-like nephritis. Methods: 40 NZB/W F1 mice were subdivided into 4 groups and intraperitoneally injected with recombinant SERPINB3 (7.5 \u3bcg/0.1 mL or 15 \u3bcg/0.1 mL) or PBS (0.1 mL) before (group 1 and 2) or after (group 3 and 4) the development of proteinuria ( 65100 mg/dl). Two additional mice groups were provided by including 20 MRL/lpr mice which were prophylactically injected with SERPINB3 (10 mice, group 5) or PBS (10 mice, group 6). Time of occurrence and levels of anti-dsDNA and anti-C1q antibodies, proteinuria and serum creatinine, overall- and proteinuria-free survival were assessed in mice followed up to natural death. Histological analysis was performed in kidneys of both lupus models. The Th17:Treg cell ratio was assessed by flow-cytometry in splenocytes of treated and untreated MRL/lpr mice. Statistical analysis was performed using non parametric tests and Kaplan-Meier curves, when indicated. Results: Autoantibody levels and proteinuria were significantly decreased and time of occurrence significantly delayed in SERPINB3-treated mice vs. controls. In agreement with these findings, proteinuria-free and overall survival were significantly improved in SERPINB3-treated groups vs. controls. Histological analysis demonstrated a lower prevalence of severe tubular lesions in kidneys of group 5 vs. group 6. SERPINB3-treated mice showed an overall trend toward a reduced prevalence of severe lesions in both strains. Th17:Treg ratio was significantly decreased in splenocytes of MRL/lpr mice treated with SERPINB3, compared to untreated control mice. Conclusions: SERPINB3 significantly improves disease course and delays the onset of severe glomerulonephritis in lupus-prone mice, possibly inducing a more tolerogenic immune phenotype

Polarization of TH2 response is decreased during pregnancy in systemic lupus erythematosus

This study evaluated some cytokines involved in the Th1-Th2 shift during pregnancy in patients with systemic lupus erythematosus (SLE) and healthy women. Twenty-seven consecutive successful pregnancies in 26 SLE patients and 28 pregnancies in 28 matched healthy subjects, as controls, were enrolled and prospectively studied. Sera obtained at first and third trimesters of pregnancy were tested for IL-1α, IL-1β, IL-2, IL-6, IL-8, IL-10, IL-12p70, INF-γ, and TNF-α with a highly sensitive, multiplexed sandwich ELISA (SearchLight Human Inflammatory Cytokine Array). Statistics were performed by SPSS package. IL-8 serum levels were higher in the first (P<0.0001) and third (P=0.003) trimesters of pregnancy in SLE patients compared with controls, INF-γ serum levels in the third trimester (P=0.009), and IL-10 serum levels in the first and third trimesters (P=0.055 and P<0.0001, respectively). IL-2 (r=0.524 P=0.010), IL-12 (r=0.549 P=0.007), IFN-γ (r=0.492 P=0.017), and IL-6 (r=0.515 P=0.020) serum levels correlated with disease activity in SLE patients in the first trimester of pregnancy. Cytokine profile was similar in patients with and without lupus nephritis both in the first and in the third trimesters of pregnancy. IL-8 serum levels were lower in patients with a previous diagnosis of antiphospholipid antibody syndrome compared with those without, both in the first and in the third trimesters of pregnancy. In SLE patients, a lower than expected decrease in Th1 cytokine serum levels was observed in the third trimester of gestation which could contribute to a lower Th2 cytokine polarization during pregnancy

Detection of serum anti-B/B' UsnRNP antibodies in patients with connective tissue diseases by immunoblotting

Objective: To investigate the reliability of the immunoblot method in the detection of serum immunoreactivity towards the B/B' polypeptides of U small nuclear ribonucleoproteins (UsnRNP) and to assess the significance of these antibodies in connective tissue disease (CTD) patients. Methods: We tested the sera of 348 patients with CTD (101 SLE, 51 systemic sclerosis, 53 primary Sjogren's syndrome, 27 poly/dermatomyositis, 15 rheumatoid arthritis and 101 overlap CTD), of 31 matched healthy subjects and 13 patients with primary Epstein-Barr virus (EBV) infection with high titre IgG anti-EBV antibodies. IgG anti-UsnRNP antibodies were determined by immunoblotting on nuclear extract from Raji cells (an EBV-immortalised human B lymphoid cell line) and Jurkat cells (a human T lymphoid cell line). Anti-dsDNA antibodies were detected by indirect immunofluorescence on Crithidia luciliae and anti-ENA by counterimmunoelectrophoresis. Anti-dsDNA activity and avidity were measured in SLE sera by ELISA with Scatchard analysis. Results were statistically analysed by chi-square and Mann-Whitney tests. Results: A high frequency of anti-B/B' antibodies was found in the sera of CTD patients, confined to SLE (54.4%) and overlap CTD with SLE features (55,2%). Anti-B/B' immune reactivity was closely associated with other anti-UsnRNP specificities, gel precipitating anti-nRNP and anti-P antibodies. Nine out of 15 (60%) anti-B/B' positive/anti-ENA negative lupus sera on Raji blots were confirmed to be positive also on Jurkat blots. The sera from patients with EBV infection provided, on Raji blots, completely different band patterns from those obtained with auto-immune sera. Conclusions. The Sm B/B' proteins are the predominant or, at least, the most frequently targeted antigens of the UsnRNP auto-immune response in SLE and "lupus-like" overlap CTD. Moreover, anti-B/B' is diagnostically specific for CTD with SLE features. Immunoblotting on human B lymphoid cells is a reliable method, in terms of sensitivity and specificity, for the detection of anti-Sm B/B' antibodies

[Myositis specific and myositis associated autoantibodies in idiopathic inflammatory myopathies: a serologic study of 46 patients]

Objective. To characterize serum autoantibody profiles of patients with idiopathic inflammatory myopathies (IIM) by searching for myositis-specific (MSA) and myositis-associated (MAA) antibodies with sensitive and specific laboratory tests. Methods. We tested the sera from 46 Caucasian patients diagnosed as affected with IIM at the Division of Rheumatology of Padova University (21 polimyositis, PM; 22 dermatomyositis, DM; 3 myositis overlap syndrome). All patients had definite IIM according to the criteria of Bohan-Peter. MSA including anti-tRNA synthetase (anti-Jo-1 and others) and anti-Mi-2 were determined by RNA immunoprecipitation and a modified immunoblot test, respectively. MAA (-U1RNP, -U2RNP, RoRNP, PM/Scl, Ku) were detected by counterimmunoelectrophoresis and immunoblot. Results. Serum MSA and/or MAA were found in 30/46 (65%) patients with IIM. Twenty-three patients (50%) were positive for at least one MSA: anti-Jo-1 in 15 (33%), anti-Mi-2 in 6 (13%), and other anti-tRNA synthetase in 3 (6%).One patient was anti-Jo-1/Mi-2 positive. Moreover, 18 patients (39%) were positive for at least one MAA: anti-Ro/SSA in 13 (28%), anti-U1RNP in 4 (9%), anti-PM/Scl in 1 (2%) and anti-Ku in 1 (2%). Coexisting MSA and MAA were observed in 8 patients (17%), anti-Jo-1/SSA positive in most cases. Anti-Jo-1 was predominantly associated with PM (57% in PM vs 14% in DM), whereas anti-Mi-2 was exclusively found in DM patients (27%). Anti-synthetase antibodies were closely associated with interstitial lung disease and polyarthritis; anti-Mi-2 positive DM patients did not have lung involvement. Notably, anti-Ro/SSA antibody was frequently observed and almost equally detected in either PM or DM (about 30%): in more than 50% of cases the antibody was associated with one MSA. Conclusions. By means of analytically reliable methods, MSA was detected in 50% of our IIM patients. Searching for MSA in patients with IIM is recommended because of its diagnostic and prognostic value