SETTINGS AND DESIGN: Case-control study at Rheumatology Clinic of Universiti Sains Malaysia Hospital.
SUBJECTS AND METHODS: The sera of SLE patients and HCs were tested for the presence of anti-CLIC2 and anti-HMGB1 autoantibodies using human recombinant proteins and ELISA methodologies. Other serological parameters were evaluated according to routine procedures, and patients' demographic and clinical data were obtained.
STATISTICAL ANALYSIS: Mann-Whitney U-test, Chi-square test, Fisher's exact test, and receiver operating characteristic analysis.
RESULTS: Anti-CLIC2 autoantibody levels were significantly higher in SLE patients compared to HCs (P = 0.0035), whereas anti-HMGB1 autoantibody levels were not significantly elevated (P = 0.7702). Anti-CLIC2 and anti-HMGB1 autoantibody levels were not associated with ANA pattern, anti-dsDNA, and CRP. Interestingly, SLEDAI score (≥6) was associated with anti-CLIC2 (P = 0.0046) and with anti-HMGB1 (P = 0.0091) autoantibody levels.
CONCLUSION: Our findings support the potential of using anti-CLIC2 autoantibodies as a novel biomarker for SLE patients. Both anti-CLIC2 and anti-HMGB1 autoantibody levels demonstrated potential in monitoring SLE disease activity.
METHODS: An indirect enzyme-linked immunosorbent assay (ELISA) was developed to evaluate the usefulness of USM.TOXO1 antigen for the detection of IgG antibodies against Toxoplasma gondii in human sera. Whereas the reactivity of the developed antigen against IgM antibody was evaluated by western blot and Dot enzyme immunoassay (dot-EIA) analysis.
RESULTS: The diagnostic performance of the new antigens in IgG ELISA was achieved at the maximum values of 85.43% and 81.25% for diagnostic sensitivity and specificity respectively. The USM.TOXO1 was also proven to be reactive with anti- T. gondii IgM antibody.
CONCLUSIONS: This finding makes the USM.TOXO1 antigen an attractive candidate for improving the toxoplasmosis serodiagnosis and demonstrates that multiepitope antigens could be a potential and promising diagnostic marker for the development of high sensitive and accurate assays.
METHODOLOGY/PRINCIPAL FINDINGS: Using in silico tools, we designed and expressed four novel P. knowlesi protein products to address the distinct lack of suitable serosurveillance tools: PkSERA3 antigens 1 and 2, PkSSP2/TRAP and PkTSERA2 antigen 1. Antibody prevalence to these antigens was determined by ELISA for three time-points post-treatment from a hospital-based clinical treatment trial in Sabah, East Malaysia (n = 97 individuals; 241 total samples for all time points). Higher responses were observed for the PkSERA3 antigen 2 (67%, 65/97) across all time-points (day 0: 36.9% 34/92; day 7: 63.8% 46/72; day 28: 58.4% 45/77) with significant differences between the clinical cases and controls (n = 55, mean plus 3 SD) (day 0 p<0.0001; day 7 p<0.0001; day 28 p<0.0001). Using boosted regression trees, we developed models to classify P. knowlesi exposure (cross-validated AUC 88.9%; IQR 86.1-91.3%) and identified the most predictive antibody responses.
CONCLUSIONS/SIGNIFICANCE: The PkSERA3 antigen 2 had the highest relative variable importance in all models. Further validation of these antigens is underway to determine the specificity of these tools in the context of multi-species infections at the population level.
MATERIALS AND METHODS: A total of 60 subjects were selected for this study. 40 subjects presented with periodontitis, which included 20 snuff users (SP) and 20 nonsnuff users (NS). 20 periodontally healthy patients formed the controls (healthy control: HC). The clinical parameters recorded were gingival index (GI), plaque index, calculus index, bleeding on probing (BOP), probing depth (PD), recession (RC), and clinical attachment level (CAL). The IL-1 β and IL-8 levels were assessed through enzyme-linked immunosorbent assay (Quantikine(®)). Analysis of variance (ANOVA), post-hoc Tukey's, Kruskal-Walli's ANOVA and Mann-Whitney test was used for comparison among groups and P > 0.05 was considered statistically significant.
RESULTS: No significant difference was seen in levels of IL-1 β and IL-8 between SP and NS groups (P = 0.16, 0.97). However, both the periodontitis groups (SP and NS) had increased IL-β levels when compared to HC group (P = 0.01, 0.001). The snuff users showed significant increase in GI, BOP, RC, and CAL when compared with NS (P = 0.002, 0.001, 0.012, 0.002) whereas NS group had significant increase in PD (P = 0.003).
CONCLUSION: Within the limitations of this study, use of snuff does not affect the host inflammatory response associated with periodontitis and leads to RC and increased CAL due to local irritant effect.