ABSTRACT
OBJECTIVE: The aim of the present study was to investigate the immunomodulating role of fat-soluble vitamins in 25 patients with primary SS (pSS) and 15 healthy individuals. METHODS: Plasma levels of vitamins A, D and E were determined by HPLC. Peripheral NK, NK T cells, T-cell subsets, B cells, IL-10 producing Tr1 cells, CD4(+)CD25(+) Treg cells and Th17 were determined by flow cytometry. Various Th1- and Th2-soluble cytokines were assessed by ELISA, whereas intracytoplasmic cytokines (IFN-gamma, IL-4, -10 and -17) were measured by flow cytometry. Correlation was assessed between vitamin levels and immunological and clinical parameters. RESULTS: Vitamin A levels did not differ between patients and controls, yet in patients with extraglandular manifestations (EGMs) a significant decrease in vitamin A levels was apparent compared with pSS patients without EGMs (P = 0.005). Vitamin E levels were increased in patients compared with controls (P = 0.004), whereas vitamin D levels were similar in pSS and control subjects. In patients, vitamin A showed a positive correlation with both NK cell (P = 0.038) and Th17 cell (P = 0.025), and a negative correlation with Schirmer's test values (P = 0.035). Positive correlation was found between vitamin E and NK cells (P = 0.043), Th1 cells (P = 0.049) and the Th1/Th2 ratio (P = 0.043). In the control group, we found correlation between vitamin E and serum IL-10 levels (P = 0.003). CONCLUSIONS: Our data suggest that fat-soluble vitamins may be important in immunoregulatory processes in patients with pSS.
Subject(s)
Sjogren's Syndrome/immunology , Vitamins/immunology , Aged , Cytokines/blood , Female , Humans , Interleukin-10/blood , Killer Cells, Natural/immunology , Lymphocyte Subsets/immunology , Male , Middle Aged , Th1 Cells/immunology , Th2 Cells/immunology , Vitamin A/immunology , Vitamin D/immunology , Vitamin E/immunologyABSTRACT
OBJECTIVE: Anti-cyclic citrullinated peptide (CCP) antibodies have emerged as sensitive and specific serological markers of rheumatoid arthritis (RA). However, antibodies to several other citrulline-containing proteins, including citrullinated fibrin and vimentin, have been detected in patients with RA, suggesting that citrulline is an essential constituent of autoantigens for RA-specific autoantibodies. We examined the diagnostic performance of the newly developed anti-mutated citrullinated vimentin (MCV) antibody assay. METHODS: Concentrations of anti-MCV, anti-CCP2, and rheumatoid factors (RF) were determined in the sera of 237 individuals: 119 patients with RA and 118 controls, including patients with other rheumatic diseases and healthy subjects. Diagnostic properties were compared by receiver-operating characteristic curve analysis. RESULTS: Using manufacturer's recommended cutoff values, sensitivity and specificity of anti-MCV antibodies were 75.6% and 91.5% in RA, compared to 66.4% and 98.3% for anti-CCP2. Introducing cutoff values to obtain the same 95% specificity resulted in decreased sensitivity of the anti-MCV test (69.7%) and increased sensitivity of the anti-CCP2 test (74.8%). At optimal cutoff levels, 29.4% of IgM RF-negative cases as well as 13.3% of anti-CCP2-negative cases in the RA group were anti-MCV-positive. Double-positivity for anti-MCV and anti-CCP2 provided 98.3% specificity with 97.5% positive predictive value in RA. CONCLUSION: Overall, the performance of the novel anti-MCV ELISA for the diagnosis of RA is similar to that of the anti-CCP2 test [area under the curve 0.853 (95% CI 0.801-0.905) vs 0.910 (95% CI 0.873-0.946); p not significant]. As the diagnostic spectrum of the anti-MCV assay is somewhat different from that of anti-CCP2, the combined application of the 2 assays can improve the laboratory diagnostics of RA.