Impact of Autoantibodies to Complement Components on the Disease Activity in SLE.

INTRODUCTION: Systemic Lupus Erythematosus (SLE) is a chronic multi-system autoimmune disease with varied clinical presentations. Complement components are the major players in disease pathogenesis. This retrospective cross-sectional study was aimed at assessing the role of autoantibodies to these complement components and their association disease activity in newly diagnosed SLE patients from India. METHOD: Clinically diagnosed SLE patients (n=57) classified as per 2015 ACR/SLICC revised criteria were enrolled between November 2016 to April 2017. Patients' sera were tested for C3 and C4 by nephelometry, while serum levels of factor H, factor P (properdin) as well as autoantibodies to C3, C4, factor H and factor P were detected by ELISA. GraphPad Prism Version 6.01 was used for statistical analysis. Mean, SD, SEM were calculated. Mann Whittney U-test, ANOVA, Chi-square test, Odd's Ratio were calculated. Pearson's correlation was used to study relativeness of the study parameters. RESULTS: Among the 57 SLE patients, low C3 were seen in 51% patients, low C4 in 49%, low factor H in 19% and low factor P in 49% patients. Positivity for autoantibodies against complement components, anti-C3 were seen in 42% patients, anti-C4 in 7%, anti-factor H in 19% and anti-factor P in 28% patients. Serum levels of C3 (p=0.0009), C4 (p=0.0031) and anti-C3 autoantibodies (p=0.0029) were significantly associated with ACR/SLICC 2015 scores. CONCLUSION: Hypocomplementemia was found to be associated with higher disease damage score in newly diagnosed SLE patients. This study adds novel arguments for the importance of the anti-C3 autoantibodies as a marker of SLE.

Fibrotic Cytokine Interplay in Evaluation of Disease Activity in Treatment Naïve Systemic Sclerosis Patients from Western India.

BACKGROUND: : Systemic sclerosis (SSc) is a demyelinating disease of skin, subcutaneous tissue, muscles and internal organs, with fibrosis as an important pathological event. AIM: : To understand cytokine interplay of IL-1ß, IL-4 and IL-6 and their association with disease activity in treatment naïve active cases of systemic sclerosis from Western India. METHODS: Twenty-five SSc patients as per ACR-EULAR 2013 criteria (classified based on pulmonary fibrosis and generalized fibrosis) and 25 age-sex matched controls were enrolled. Serum cytokine levels of IL-1ß, IL-4 and IL-6 were assessed by multiplex bead based immunoassay. RESULTS: Ten patients had Interstitial lung disease (ILD), whereas, 16 patients had generalized fibrosis. Anti-nuclear antibodies were seen in 22 patients (88%); antiScl70 in 15 patients (60%) and anti-Centromere antibodies in 5 patients (20%). Serum levels of IL-1ß in patients were significantly higher than healthy controls (p=0.0006). IL-4 levels in all SSc patients were marginally raised (p=0.0102), while IL-6 levels were significantly raised (p<0.0001). IL-4 was found to be significantly raised in SSc patients with ILD (p=0.021) as compared to patients without ILD. IL-1ß (p=0.0293) and IL-4 (p<0.0001) were significantly higher in SSc patients with fibrosis. On the contrary, IL-6 levels in patients with fibrosis were found to be lower than in patients without fibrosis. CONCLUSION: Significantly raised cytokine levels among treatment naïve systemic sclerosis patients were found to be associated with higher disease severity in our study. Higher levels of IL-1ß and IL-6 indicated an active inflammatory status, whereas significantly raised IL-4 levels indicated at higher fibrotic activity.

Catalytic antibodies in patients with systemic lupus erythematosus.

OBJECTIVE: Antibodies with catalytic (hydrolytic) properties to DNA or RNA have been reported in systemic lupus erythematosus (SLE). However, it is well known that ethnicity plays an important role in the presentation of SLE and severity of the disease; hence, these data may not truly represent a general feature of all SLE patients. Therefore, we have analyzed the hydrolyzing activity of immunoglobulin G (IgG) of SLE patients from the Indian population with an aim to decode whether the catalytic antibody response represents part of an active disease process. METHODS: IgGs were isolated from the sera of 72 consecutive patients diagnosed with SLE. As a control, IgGs from healthy donors were used. The catalytic activity of IgG was measured by PFR-MCA and affinity-linked oligonucleotide nuclease assay. RESULTS: IgGs from patients with SLE from the Indian subcontinent displayed significantly higher hydrolysis rates of both the surrogate substrate, PFR-MCA, and the DNA than IgG from healthy individuals. Intergroup comparisons of the IgG-PFR-MCA interactions with clinical manifestations of the disease demonstrated a significantly increased level of hydrolysis among the patients with renal involvement who tested positive for anti-dsDNA antibodies. The PFR-MCA hydrolysis also appears to be associated with the active disease (p=0.0988, vs. inactive group). CONCLUSION: The prevalence of catalytic antibodies represents a general feature of SLE patients, irrespective of their origin.