A novel way to evaluate autoantibody interference in samples with mixed antinuclear antibody patterns in the HEp-2 cell based indirect immunofluorescence assay and comparison of conventional microscopic and computer-aided pattern recognition.

BACKGROUND: A major challenge of the HEp-2 cell-based indirect immunofluorescence (IIF) assays is the correct identification of the individual anti-nuclear antibodies (ANAs) if more than one is present in a sample. We created artificial mixes by pooling two different samples with a single autoantibody in different titers. Comparison of the expected and observed patterns and titers clarifies the interference between the two tested ANAs. METHODS: Serum samples with a single homogeneous or speckled ANA pattern were serially diluted and mixed in 16 combinations, providing end-point titers of 1:5,120 to 1:80 for both patterns. These mixes were tested by a HEp-2 IIF assay and were evaluated by conventional evaluation, the EUROPattern (EPa) system and on-screen analysis. RESULTS: Homogeneous pattern can alter the identification of the speckled pattern much more than vice versa, but both has an interfering effect on the other. The effect of the interfering on the tested pattern was higher if the titer of the former one was higher. The pattern recognition efficacy of conventional and the on-screen evaluation was similar and superior compared to the EPa analysis. CONCLUSIONS: The application of artificial mixed samples can help the evaluation of the efficacy of manual and computer-aided ANA HEp-2 pattern recognition.

Idiopathic inflammatory myopathies, signified by distinctive peripheral cytokines, chemokines and the TNF family members B-cell activating factor and a proliferation inducing ligand.

OBJECTIVE: Serum cytokines play an important role in the pathogenesis of myositis by initiating and perpetuating various cellular and humoral autoimmune processes. The aim of the present study was to describe a broad spectrum of T- and B-cell cytokines, growth factors and chemokines in patients with idiopathic inflammatory myopathies (IIMs) and healthy individuals. METHODS: A protein array system, denoted as multiplex cytokine assay was utilized to measure simultaneously the levels of 24 circulating cytokines, including B-cell activating factor (BAFF) and a proliferation inducing ligand (APRIL) of patients with IIMs and healthy individuals. Additionally, correlational clustering and discriminant function analysis (DFA), two multivariate, supervised analysis methods were employed to identify a subset of biomarkers in order to describe potential functional interrelationships among these pathological cytokines. RESULTS: Univariate analysis demonstrated that a complex set of immune and inflammatory modulating cytokines are significantly up-regulated in patients with IIMs relative to unaffected controls including IL-10, IL-13, IFN-α, epidermal growth factor (EGF), VEGF, fibroblast growth factor (FGF), CCL3 [macrophage inflammatory protein (MIP-1α)], CCL4 (MIP-1ß) and CCL11 (eotaxin), whereas G-CSF was significantly reduced in IIM patients. Correlational clustering was able to discriminate between, and hence sub-classify patients with IIMs. DFA identified EGF, IFN-α, VEGF, CCL3 (MIP-1α) and IL-12p40, as analytes with the strongest discriminatory power among various myositis patients and controls. CONCLUSIONS: Our findings suggest that these factors modulate myositis pathology and help to identify differences between subsets of the disease.

Anti-neutrophil cytoplasmic antibody testing by indirect immunofluorescence: Computer-aided versus conventional microscopic evaluation of routine diagnostic samples from patients with vasculitis or other inflammatory diseases.

BACKGROUND: Detection of anti-neutrophil cytoplasmic antibodies (ANCA) by indirect immunofluorescence assays (IFA) is of diagnostic importance in vasculitides and some other inflammatory diseases. Automation of IFA may be beneficial in high-throughput clinical laboratories. An analytical appraisal of the EUROPattern (EPa) automated microscope and image analysis system has not been reported in a routine clinical laboratory setting testing samples from both vasculitis and non-vasculitis patients. METHODS: Results of EPa and on-screen ANCA pattern recognition of 568 consecutive routine serum samples were compared to those of conventional visual evaluation. RESULTS: Agreement of discrimination between negative and non-negative samples was 86.1% comparing EPa and conventional reading, and it increased to 96.7% after on-screen user validation. Importantly, from the 334 samples classified as negative by EPa 328 (98.2%) were also negative by conventional evaluation. Pattern recognition showed 'moderate' agreement between classical microscopic and EPa analysis (κ = 0.446) and 'very good' agreement after user validation (κ = 0.900). Misclassification by EPa was dominantly due to the presence of anti-nuclear/cytoplasmic antibodies (incorrect pattern, 80/568) and the lower fluorescence cut-off of the automated microscope (false positives, 73/568). CONCLUSIONS: Automated ANCA testing by EPa is a reliable alternative of classical microscopic evaluation, though classification of sera needs correction by trained personnel during on-screen validation.

Association between human paraoxonase 1 activity and intima-media thickness in subjects under 55 years of age with carotid artery disease.

BACKGROUND: Human serum paraoxonase (PON1) protects lipoproteins against oxidation by hydrolyzing lipid peroxides in oxidized low-density lipoprotein (oxLDL); therefore, it may protect against atherosclerosis. PON1 activity and polymorphisms have been inconsistently associated with carotid artery disease. The goal of this study was to clarify the role of PON1 activity and phenotype on carotid artery disease and its correlation with some inflammatory and immune markers in subjects under 55 years with early-onset carotid atherosclerosis. METHODS: Sixty patients with occlusive carotid artery disease and 30 healthy controls were enrolled. Intima-media thickness (IMT) was measured by high-resolution ultrasound of both common carotid arteries. Anti-oxLDL antibody levels were determined by ELISA. RESULTS: In the whole study population we found a negative correlation between PON1 activity and IMT (r = -0.27, p = 0.011), and between salt-stimulated PON1 activity and IMT (r = -0.24, p = 0.02). Both PON1 activity and salt-stimulated PON1 activity negatively correlated with anti-oxLDL levels (r = -0.28, p = 0.008; r = -0.26, p = 0.01). PON1 activity was lower in patients compared to controls; however, the difference was not significant.PON1 phenotype distribution of patients and controls did not differ significantly. CONCLUSION: The importance of PON1 activity as a predictive risk factor for early-onset occlusive carotid artery disease should be assessed in future studies.

Evaluation of antibodies to oxidized low-density lipoprotein and assessment of C-reactive protein in acute coronary syndrome and stable coronary artery disease.

The aim was to measure the level of antibodies to oxidized LDL (oxLDL) and C-reactive protein (CRP) in the serum of patients with acute coronary syndrome (ACS). The results were correlated with data obtained from patients with stable coronary artery disease (stable CAD) and healthy controls. Thirty-three patients with ACS and 62 stable CAD patients were enrolled in the study. Fifty healthy individuals served as controls. The evaluation of anti-oxLDL autoantibodies was performed by ELISA, while CRP levels were measured by turbidimetry. The level of antibodies to oxLDL was significantly higher in both groups of patients with ACS and stable CAD compared to controls. The comparison between the acute and stable groups showed that anti-oxLDL levels were higher in the acute group, but because of high SD, the difference was not significant. By performing group analysis, anti-oxLDL levels were found to be significantly higher in ACS patients with unstable clinical state (circulatory insufficiency, malignant arrhythmias, recurring ischemic pain, need for urgent coronary intervention and death). CRP level in patients with ACS was significantly higher than in those with stable CAD. A positive correlation was found between anti-oxLDL antibodies and CRP levels both in patients with ACS and stable CAD. The association between the two biomarkers was stronger in the ACS group. In conclusion, our findings support the notion that the presence of antibodies to oxLDL, a plaque-specific antigen, plays a major role as a predictor of complicated manifestations of ACS.

Determination of ligand binding capacity of soluble Fc gamma RII and Fc gamma RIII in sera of patients with SLE.

BACKGROUND: Soluble, human low affinity Fcgamma receptors, such as sFcgammaRII and sFcgammaRIII, are known to play a pathologic role in different diseases. Sandwich ELISAs had previously been applied for the specific detection and determination of these soluble receptors. In these ELISAs, commercial monoclonal antibodies (Ab) were used as capture antibodies with monoclonal or polyclonal antibodies serving as detector Abs. Increased levels of cell-free FcgammaRIII have been detected in patients with lupus but the functions and levels of sFcgammaRII have not been fully characterized yet. OBJECTIVES: The aim of this work was to determine the ligand binding capacities and levels of soluble FcgammaRII and FcgammaRIII in sera of patients with systemic lupus erythematosus (SLE). Moreover, correlation between the levels of sFcgammaRII and sFcgammaRIII and the clinical activity of the disease were investigated. METHODS: Sera of 47 patients with SLE, and 51 healthy subjects were analyzed. In the newly developed indirect sandwich ELISAs commercial monoclonal anti-FcgammaRs are used as capture antibodies, and the ligand of FcgammaRII and FcgammaRIII, an artificial immune complex (IC), serves as a detection component replacing the second antibodies used in previous methods. RESULTS: The ligand binding capacity of both soluble FcgammaRII and sFcgammaRIII were elevated in the sera of SLE patients compared to control samples. This increase was significant in patients with the active disease (n = 30; p < 0.01). It was also revealed that a substantial part of the soluble Fcgamma receptors in these patients was bound in vivo to circulating IC. CONCLUSION: These newly developed ELISAs are probably more phisiologically relevant than other previous assays because they detect the circulating receptors on the basis their in vitro ligan binding capacities. Therefore this method can separately measure the levels of the soluble, free FcgammaRs and those bound circulating IC in vivo.

Elemental Analysis of Whole and Protein Separated Blood Serum of Patients with Systemic Lupus Erythematosus and Sjögren's Syndrome.

Systemic lupus erythematosus (SLE) and Sjögren's syndrome (SS) are systemic autoimmune diseases with complex symptoms and pathogenesis that are still not completely understood. Several studies showed that the trace element homeostasis and also the levels of antioxidant plasma proteins are changed in autoimmune disorders; however, these results are controversial. In this study, the potassium (K), calcium (Ca), magnesium (Mg), copper (Cu), zinc (Zn), and iron (Fe) concentrations of the serum and proteins-immunoglobulin G (IgG), transferrin (Trf), albumin (Alb), and ceruloplasmin (Cp)-separated from serum samples by affinity chromatography were determined in patients with SLE and SS. Ca and K levels were found to be decreased in the case of both disorders compared to the control group, and the competitive antagonism of Cu and Zn was also observed: elevated Cu concentration together with a lower Zn concentration was measured in the sera of patients with autoimmune diseases. After fractionation, the trace element concentration of protein containing fractions altered to that of the control group. In case of the autoimmune disorders, the highest Cu concentration was determined in the Alb-containing protein fractions while the Zn level decreased in the Alb and increased in the Cp as well as in the IgG- and Trf-containing fractions compared to the healthy samples. Changes have also been found in the level and distribution of K and Ca.

Microscopic colitis: a retrospective study of clinical presentation in 53 patients.

AIM: To evaluate the relationship between symptoms and microscopic colitis (MC) subtypes: to test whether collagenous colitis (CC) and/or lymphocytic colitis (LC) might be related to both constipation and diarrhea. METHODS: A cohort of patients with independently confirmed typical histopathological changes was investigated. Fifty-three patients with histologically proved MC (46 with CC, 7 with LC) were included. The existence of diarrhea or constipation and the co-existence of autoimmune diseases were also investigated and all data were retrospectively analyzed. RESULTS: Twenty-three (43.39%) of MC patients had chronic constipation (20 in CC, 3 in LC patients). Twenty-four (45.28%) of MC patients had autoimmune disease and the diagnosis of autoimmune disease was always prior to MC. Sjögren's syndrome was associated only with the constipation subgroup. CONCLUSION: The Janus face of MC resembles the subgroups of irritable bowel syndrome. The co-existence of autoimmune diseases and MC is confirmed in both the constipation and diarrhea subgroups.

[Analysis of paraoxonase activity and lipid profile in lupus patients]. / Lipidprofil és paraoxonáz aktivitáis vizsgálata szisztémás lupus erythematosusban.

INTRODUCTION: Immune-inflammatory processes play important role in the pathogenesis of atherosclerosis. Therefore, increasing attention is focused on rheumatic diseases with chronic inflammation, such as systemic lupus erythematosus. Besides direct influences, inflammation may modify the development of atherosclerosis by other mechanisms. AIMS: To examine paraaoxonase activity and lipid profile in lupus patients. METHODS: Authors entered 37 definitive lupus patients and 30 age- and sex-matched normal controls into the present study. Patients' age was 40.8 +/- 13.9 year, follow-up time 6.7 +/- 6.2 year, disease activity index 2.8 +/- 3.4. Lipid parameters (total cholesterol, LDL-C, HDL-C, Apo-AI and ApoB) were determined by an autoanalyser, paraoxonase and arylesterase activities were measured spectrophotometrically. Phenotypic distribution of the enzyme was determined by dual substrate method. Anti-oxLDL was measured by ELISA method, CRP by automatised immunoassay. Statistical analysis was performed by SPSS program. RESULTS: Despite of long disease duration and low inflammatory activity authors found significantly (p < 0.001) decreased paraoxonase activity (121.9 +/- 65.9 U/mL) (p < 0.001) in lupus as compared to control (188.1 +/- 78.9 U/mL), which correlated with the presence of atherothrombotic complications (p = 0.009). High activity BB phenotype did not occur in lupus. Lipid parameters and arylesterase activity were within normal range in both groups. No significant correlation was found between paraoxonase activity and disease activity index, dose of corticosteroid therapy, CRP and anti-oxLDL level. Arylesterase activity did not differ in lupus and control groups. CONCLUSIONS: Present results suggest that other mechanisms, e.g. antibodies, genetic factors, alteration in the distribution of HDL-subfractions or ensyme abnormalities in HDL remodelling may stand at the background of reduced paraoxonase activity in lupus.

[Comparative hematologic and immunologic studies of patients with splenectomy and spleen autotransplantation]. / Splenectomizált és lép autotranszplantált betegek összehasonlító haematologiai és immunologiai vizsgálatai.

We compared changes in haematological and immunological parameters of patients with splenectomy (n=24), splenectomy plus spleen autotransplantation (n=12) and healthy controls (n=23). In the autotransplantation group pieces of the removed spleen were placed into the omentum with good visible circulation. Significant alterations in the hematological status and in some immunological parameters were observed in both groups of patients who were operated on compared to those in the control group. There was no difference, however, between the results of the two groups of operated patients. Therefore, we emphasize the importance of vaccination in patients with spleen autotransplantation in order to prevent potential sepsis. In addition, we recommend the possible further use of spleen autotransplantation.

Seroreactivity against Saccharomyces cerevisiae in patients with Crohn's disease and celiac disease.

AIM: To explore whether there was anti-Saccharomyces cerevisiae antibodies (ASCA) positivity in our patients with biopsy-confirmed celiac disease. METHODS: A cohort of patients with inflammatory bowel diseases (42 patients with Crohn's disease and 10 patients with ulcerative colitis) and gluten sensitive enteropathy (16 patients) from Debrecen, Hungary were enrolled in the study. The diagnosis was made using the formally accepted criteria. Perinuclear antineutrophil cytoplasmic antibodies (pANCA) and anti-Saccharomyces cerevisiae antibodies (ASCA), antiendomysium antibodies (EMA), antigliadin antibodies (AGA) and anti human tissue transglutaminase antibodies (tTGA) were investigated. RESULTS: The results showed that ASCA positivity occurred not only in Crohn's disease but also in Celiac disease and in these cases both the IgG and IgA type antibodies were proved. CONCLUSION: It is conceivable that ASCA positivity correlates with the (auto-) immune inflammation of small intestines and it is a specific marker of Crohn's disease.

Evaluation of significance of lymphocyte subpopulations and non-specific serologic markers in B-cell non-Hodgkin's lymphoma patients.

The use of rituximab brought attention to the hosts' immune system and to the microenvironment in non-Hodgkin's lymphoma cases. Our aim was to identify prognostic factors that can be measured easily to indicate the current state of the patient's immune status and possible reaction against malignant cells. In the retrospective analysis (2000-2008), 66 patients diagnosed with B-cell non-Hodgkin's lymphomas were enrolled (40 women, 26 men; mean age: 51 years). White blood cells, lymphocytes, CD3 +; CD4 +; CD8 + T-cells, immunoglobulin types A; G; M, anti-cardiolipin antibody isotypes A; G; M; and levels of beta-2-microglobulin were measured before the initiation of the first cycle of chemotherapy, during and after 4-weeks treatment. As for CD 3+ T-lymphocytes, the absolute CD 3+ T -lymphocyte numbers were higher before (0.78 × 10(9)/L) versus during (0.27 × 10(9)/L) treatment, and increased percentages were detected in pre- (66.57 %) and post-treatment (75.32 %). Absolute numbers of CD 8+ T-lymphocyte levels showed reduction before (0.26 × 10(9)/L) versus during (0.10 × 10(9)/L) therapy, but were elevated after (0.28 × 10(9)/L) treatment, while increased percentage before (21.99 %) versus after (29.85 %), and during (24.56 %) versus after (29.85 %) therapy were seen. Average white blood cell numbers were increased before (9.71 × 10(9)/L) versus during (12.07 × 10(9)/L) treatment, while decreased numbers could be observed, after (5.47 × 10(9)/L) treatment. IgA levels were decreased before (2.51 g/L) versus after (1.63 g/L) therapy. IgG levels were higher before (12.25 g/L) vs. after (8.64 g/L) treatment. IgM levels were decreased before (1.76 g/L) and after (0.83 g/L) as well as before (1.76 g/L) versus during (0.73 g/L) treatment. Anti-cardiolipin antibody type A level were decreased before (2.76 U/ml) versus after (2.49 U/ml) treatment. Decreased level of beta-2-microglobulin could be observed before (2.91 mg/L) versus post (2.28 mg/L) chemotherapy. Findings may provide better insight into the effects of immuno-chemotherapy on the hosts' immune system.

Increased levels of anti-heat-shock protein 60 (anti-Hsp60) indicate endothelial dysfunction, atherosclerosis and cardiovascular diseases in patients with mixed connective tissue disease.

Heat-shock protein 60 (Hsp60) has been shown to provoke inflammation, and anti-Hsp60 may facilitate the development of atherosclerosis. In this study, we have investigated 30 patients with mixed connective tissue disease (MCTD) and assessed anti-Hsp60 and their relationship to cardiovascular diseases (CVD). Out of 30 patients with MCTD, 15 had CVDs. Anti-Hsp60 antibody was determined by enzyme-linked immunosorbent assay. Since endothelial dysfunction and accelerated atherosclerosis are characteristic to MCTD, a wide array of MCTD-, endothelial dysfunction- and CVD-associated parameters was investigated: serum lipid levels, paraoxonase activity (PON1), rich nuclear ribonucleoprotein U1 (anti-U1RNP), anti-endothelial cell antibodies, anti-cardiolipin and anti-ß2-glycoprotein I antibody isotypes (anti-CL and anti-ß2GPI), endothelin-1 (ET-1) levels, also intima-media thickness (IMT), a quantitative indicator of atherosclerosis. In MCTD, anti-Hsp60 antibody levels were significantly higher than in healthy individuals (p < 0.02). MCTD patients with CVD had significantly higher levels of anti-Hsp60 compared to MCTD without CVD (p = 0.001). Patients with MCTD had significantly lower high-density lipoprotein cholesterol (p = 0.02) and PON activity (p < 0.001), and significantly increased systolic (p < 0.0002) and diastolic (p < 0.001) blood pressure compared to healthy individuals. Anti-U1RNP levels (p < 0.002) and IMT were higher in patients compared to controls (p = 0.002). The CVD-positive MCTD patients had increased anti-Hsp60 (p < 0.0013), anti-CL IgG (p = 0.0005), ET-1 serum concentration (p < 0.05) and IMT levels (p < 0.001) compared to MCTD patients without CVD. Anti-Hsp60 showed a strong correlation with anti-oxLDL (r = 0.36, p = 0.01) and serum ET-1 (r = 0.62, p < 0.001) and negative correlation with PON activity (r = -0.47, p = 0.01). Anti-Hsp60 indicates endothelial injury, CVD, and can function as a novel atherosclerotic risk factor, also a valuable diagnostic marker in patients with MCTD.

Altered Th17 cells and Th17/regulatory T-cell ratios indicate the subsequent conversion from undifferentiated connective tissue disease to definitive systemic autoimmune disorders.

A shift in the balance between Th17-cells and regulatory T-cells (Treg) is an important feature of systemic autoimmune diseases (SAID), and may also contribute to their development. Hereby, we assessed the distribution of peripheral Th17 and Treg-cells in patients with undifferentiated connective tissue disease (UCTD), the forerunner of SAIDs and followed these parameters during the development towards definitive SAIDs. Fifty-one UCTD patients were investigated and followed-up for 3 years. Flow cytometry was used to identify and follow three cell-populations: Th17-cells (CD4+IL-17+ T-cells), natural regulatory T-cells (CD4(+)CD25(bright)FoxP3(+); nTregs) and IL-10 producing Type-1 regulatory T-cells (CD4+IL-10+ T-cells; Tr1). Altogether 37.3% of these patients progressed into SAIDs. Th17-cells were increased in UCTD vs. controls, which further increased in those, whom developed SAIDs eventually. The Th17/nTreg ratio gradually increased from controls through UCTD patients, reaching the highest values in SAID-progressed patients. Regarding the Th17/Tr1 ratios, a similar tendency was observed moreover Th17/Tr1 could distinguish between UCTD patients with, or without subsequent SAID progression in a very early UCTD stage. Various immunoserological markers showed association with Th17 and Th17/nTreg at baseline, indicating the consecutive development of a distinct SAID. The derailed Th17/Treg balance may contribute to disease progression therefore could function as a prognostic marker.

Celiac disease and microscopic colitis: a report of 4 cases.

Celiac disease (CD) is an autoimmune disorder of the small intestine that occurs in genetically predisposed people at all ages. However, it can be associated also to other immunopathological disorders, and may be associated with abnormal histology in segments of the gut other than the small bowel including colonic inflammation. While guidelines for endoscopic investigation of the jejunum are well defined, no indication is defined for colonic investigation. We describe four cases of concurrent CD and microscopic colitis (MC) diagnosed at our department over a 10-year period and analyzed the main features and outcomes of CD in this setting. The symptoms of these patients were improved initially by a gluten-free diet before the onset of MC symptoms. Two of the patients were siblings and had an atypical form of CD. The other two patients with CD and MC also presented with fibrosing alveolitis and were anti-Saccharomyces cerevisiae antibody positive. The co-existence of immune-mediated small bowel and colonic inflammatory and pulmonary diseases are not well-known, and no systematic approach has been used to identify the lifelong patterns of these immune-based diseases. Patients can develop, or present with CD at any stage in life, which can co-exist with other gastrointestinal diseases of (auto-) immune origin. In addition, the familial co-existence and prevalence of MC in patients with a prior diagnosis of CD are unclear. Clinicians managing celiac disease should be aware of these associations and understand when to consider colon investigation.

Vitamin D insufficiency in a large MCTD population.

OBJECTIVES: The aim of the present study was to evaluate the vitamin D status in patients with mixed connective tissue disease (MCTD) and to determine which clinical symptoms, laboratory parameters and endothelial cell markers are associated with low vitamin D levels. METHODS: 125 female MCTD patients and 48 age- and sex-matched healthy controls were enrolled in the study. The clinical symptoms, autoantibodies (anti-U1-RNP, anti-cardiolipin - anti-CL and anti-endothelial cell antibody - AECA), serum cytokines (IFN-γ, IL-6, IL-12, IL-23, IL-17 and IL-10), soluble endothelial cell markers (endothelin, thrombomodulin - TM, and von Willebrand factor antigen - vWFAg) and serum lipids (total cholesterol, triglyceride, LDL-C, HDL-C, apolipoprotein A1, and apolipoprotein B) were investigated for an association with vitamin D levels by univariate and multivariate statistical analyses. RESULTS: The mean vitamin D levels were significantly lower in MCTD patients, as compared with the control group (26.16±13.50ng/ml vs. 34.92±9.64ng/ml; p<0.001). In laboratory parameters, vitamin D levels were inversely associated with serum IL-6 (p<0.001), IL-23 (p=0.011), IL-10 (p=0.033) cytokine levels, TM (p=0.001) and endothelin (p=0.033) levels. Low vitamin D levels were also significantly associated with carotid artery intima media thickness (p<0.001), fibrinogen (p=0.010), total cholesterol (p=0.042) and ApoA1 (p=0.004) levels. Among the clinical symptoms, the cardiovascular involvement showed an inverse correlation with vitamin D status in MCTD (p<0.001). CONCLUSIONS: The prevalence of vitamin D insufficiency is high in patients with MCTD. We assume that vitamin D insufficiency along with inflammatory parameters and lipid abnormalities may provoke cardiovascular events.

Endothelial cell markers reflecting endothelial cell dysfunction in patients with mixed connective tissue disease.

INTRODUCTION: The aim of the present study was to investigate the association between cardiovascular risk factors and endothelial dysfunction in patients with mixed connective tissue disease (MCTD) and to determine which biomarkers are associated with atherosclerotic complications, such as cardiovascular disease. METHODS: Fifty MCTD patients and 38 healthy age-matched and sex-matched controls were enrolled in this study. In order to describe endothelial dysfunction, we assessed flow-mediated dilation (FMD), nitrate-mediated dilation (NMD) and carotid artery intima-media thickness (IMT). We investigated FMD of the brachial artery after reactive hyperemia and NMD after sublingual nitroglycerin administration, while the IMT of the common carotid artery was determined by ultrasound. Anti-U1 ribonucleoprotein (anti-U1RNP) antibodies, anti-cardiolipin (anti-CL) antibodies, anti-endothelial cell antibody (AECA) and endothelial cell markers, such as soluble thrombomodulin (TM) and von Willebrand factor antigen (vWFAg), were assessed. RESULTS: The endothelium-dependent vasodilation (FMD) was significantly impaired in patients with MCTD, as compared with controls (%FMD: 4.7+/-4.2% vs. 8.7+/-5.0%; P<0.001), while the percentage NMD did not differ (%NMD: 14.3+/-6.6% vs. 17.1+/-6.7%; P=0.073). Mean carotid IMT values were higher in patients than in controls (IMT: MCTD, 0.64+/-0.13 mm vs. controls, 0.53+/-0.14 mm; P<0.001). FMD negatively correlated with disease duration, the levels of apolipoprotein A1, the paraoxonase-1 activity, and systolic blood pressure in MCTD patients. The percentage FMD was significantly lower in MCTD patients with cardiovascular diseases (CVD), than in those without CVD (%FMD: 3.5+/-2.9 vs. 5.8+/-4.8, P<0.0002), while percentage NMD did not differ between patients with and without CVDs. Serum levels of autoantibodies (anti-U1RNP, AECA and anti-CL) were significantly higher in MCTD patients and differed between MCTD patients with and without CVD. Endothelial cell markers such as soluble TM (12.2+/-8.1 ng/ml vs. 3.2+/-1.3 ng/ml; P<0.001) and vWFAg (224.1+/-115% vs. 89.4+/-27.1%, P<0.001) were the highest in MCTD patients with CVD. CONCLUSIONS: FMD is a reliable sensitive marker of endothelial cell dysfunction in MCTD. Beside the traditional risk factors, anti-U1RNP, AECA and anti-CL antibodies may be important not only in the pathogenesis of MCTD but in the induction of endothelial cell activation, and may play crucial roles in the development of early atherosclerosis in MCTD.

Autoantibodies to alfa-fodrin in patients with Hashimoto thyroiditis and Sjögren's syndrome: possible markers for a common secretory disorder.

Presence of autoantibodies to alfa-fodrin was investigated in patients with Sjögren's syndrome (n = 61), Hashimoto thyroiditis (n = 27), Sjögren's syndrome associated with Hashimoto thyroiditis (n = 31) and in healthy persons (n = 77). In each group, level of alfa-fodrin antibodies was higher than in the controls. There was no significant difference in their presence either between patients with Hashimoto thyroiditis with or without Sjögren's syndrome, or-in IgA isotype-between Sjögren's and Hashimoto thyroiditis patients. Correlation was found between the level of IgG alfa-fodrin and anti-thyroglobulin antibodies. Based on these findings, fodrin can be associated with both endocrine and exocrine glandular secretion. Antibodies to alfa-fodrin might have a role in the pathogenesis of Hashimoto thyroiditis concerning the "final common effectory pathway", secretion. Alfa-fodrin antibodies can be good markers of secretory disorders. Assessment of these autoantibodies might help the diagnosis and follow-up of patients with impaired secretory capability of not only autoimmune origin.