Comparative analysis of three methods in anti-dsDNA antibodies detection: implications for Systemic Lupus Erythematosus diagnosis.

The evaluation of anti-dsDNA antibodies represents one of the essential diagnostic and prognostic marker features in patients affected by Systemic Lupus Erythematosus (SLE). In this study, we have compared immunoblotting (IB) with Crithidia luciliae indirect immunofluorescence test (CLIFT) and chemiluminescent immunoassay (CLIA) in 91 patients referred to our hospital for anti-dsDNA antibodies detection. The concordance and correlation measured by Cohen's kappa and Spearman's coefficient respectively was significant between CLIFT and CLIA (0.70; 0,7404, P < .0001) and among CLIA and IB (0.79; 0,5377, P < 0,0001) and lower between CLIFT and IB (0.55; 0,4373, P  <0,0001). Among the 46 IB-positive samples, 14 were positive for either CLIA or CLIFT. It is noteworthy that 11 out of these 14 samples had the final diagnosis of SLE. Thirteen out of fourteen samples were also positive for anti-nucleosome antibodies as measured concomitantly in immunoblotting. While our observations are based on a limited number of samples and will have to be confirmed in a bigger cohort, they underline the contribution of immunoblotting as an additional assay in defining the anti-dsDNA antibody profile in association with other well-established methods such as CLIA and CLIFT.

Biomarkers of Glyco-Metabolic Control in Hemodialysis Patients: Glycated Hemoglobin vs. Glycated Albumin.

Background and Objectives: Glycated hemoglobin (HbA1c) dosage is considered the gold standard in glycol-metabolic monitoring, but it presents limits, which can underestimate the glycemia trend. In this regard, it was introduced the glycated albumin (GA). The aim of the study is to verify the predictivity of the GA compared to HbA1c in identifying glyco-metabolic alterations in non-diabetic and diabetic hemodialysis (HD) patients. Materials and Methods: For this purpose, we conducted a multicenter study involving one analysis laboratory and six dialysis centers in the Lazio region (Rome, Italy). Both diabetic and non-diabetic HD patients represent the study population, and the protocol included five time points. Results: The analyzed data highlighted the ability of GA to predict changes in glycemic metabolism in HD patients, and GA values are not significantly influenced, like HbA1c, by dialysis therapy itself and by comorbidities of the uremic state, such as normochromic and normocytic anemia. Thus, GA seems to reflect early glyco-metabolic alterations, both in patients with a previous diagnosis of diabetes and in subjects without diabetes mellitus. As part of this study, we analyzed two HD patients (one diabetic and one non-diabetic) in which GA was more predictive of glycol-metabolic alterations compared to HbA1c. Our study confirms the need to compare classical biomarkers used for the monitoring of glyco-metabolic alterations with new ones, likely more reliable and effective in specific subgroups of patients in which the classic biomarkers can be influenced by the preexisting pathological conditions. Conclusions: In conclusion, our evidence highlights that in uremic patients, GA shows a better ability to predict glyco-metabolic alterations allowing both an earlier diagnosis of DM and a prompt modulation of the hypoglycemic therapy, thus improving the clinical management of these patients.

[Marked increase in high-sensitivity troponin I without evidence of acute coronary syndrome]. / Marcato incremento della troponina I ad alta sensibilità in assenza di evidenza di sindrome coronarica acuta.

Troponins measured by high-sensitivity methods (hs-cTn) are the current reference biomarkers to diagnose acute myocardial infarction. Conditions other than obstructive coronary heart disease may present an increase in hs-cTn. Heterophilic antibodies can interfere with the hs-cTn dosage. We report the case of a patient affected by rheumatoid arthritis, hospitalized for syncope and atypical chest pain. Serial blood samples documented high values of high-sensitivity troponin I and normal values of creatine kinase-MB and myoglobin. Echocardiogram, coronary angiography and electrophysiological study were normal. The use of heterophilic antibody blockers defined these values as false positive results. Therefore, to diagnose acute myocardial infarction, laboratory data should be integrated with clinical information and instrumental examinations. Marker release kinetics is crucial. Finally, there may be some possible causes of heterophilic antibodies (rheumatoid arthritis, Sjogren's syndrome, systemic lupus erythematosus, mixed cryoglobulinemia, hepatitis C, infections, cancer, sarcoidosis) that could interfere with biomarker dosage.

EBV up-regulates PD-L1 on the surface of primary monocytes by increasing ROS and activating TLR signaling and STAT3.

Programmed death ligand 1 (PD-L1) (also called B7-H1) is a membrane immune-modulatory protein whose overexpression on the surface of tumor cells as well as APCs impairs T-cell-mediated killing. Viruses that establish chronic infections have developed a number of strategies to escape from immune recognition including the up-regulation of PD-L1. This study shows for the first time that the human oncovirus EBV infects human primary monocytes using HLA-DR and induced a strong up-regulation of PD-L1 expression on their surface. Searching for the underlying mechanism/s leading to this immune suppressive effect, we found that EBV activated TLR signaling, increased intracellular ROS, and phosphorylated STAT3. Targeting these molecules partially reverted PD-L1 up-regulation that correlated with an altered cytokine production and a reduction of monocyte cell survival, strongly impairing the antiviral immune response.

Quercetin induces apoptosis and autophagy in primary effusion lymphoma cells by inhibiting PI3K/AKT/mTOR and STAT3 signaling pathways.

Quercetin, a bioflavonoid contained in several vegetables daily consumed, has been studied for long time for its antiinflammatory and anticancer properties. Quercetin interacts with multiple cancer-related pathways such as PI3K/AKT, Wnt/ß-catenin and STAT3. These pathways are hyperactivated in primary effusion lymphoma (PEL), an aggressive B cell lymphoma whose pathogenesis is strictly linked to the oncogenic virus Kaposis' Sarcoma-associated Herpesvirus (KSHV). In this study, we found that quercetin inhibited PI3K/AKT/mTOR and STAT3 pathways in PEL cells, and as a consequence, it down-regulated the expression of the prosurvival cellular proteins such as c-FLIP, cyclin D1 and cMyc. It also reduced the release of IL-6 and IL-10 cytokines, leading to PEL cell death. Moreover, quercetin induced a prosurvival autophagy in these cells and increased the cytotoxic effect of bortezomib, a proteasomal inhibitor, against them. Interestingly, quercetin decreased also the expression of latent and lytic KSHV proteins involved in PEL tumorigenesis and up-regulated the surface expression of HLA-DR and calreticulin, rendering the dying cells more likely detectable by the immune system. The results obtained in this study indicate that quercetin, which does not exert any cytotoxicity against normal B cells, may represent a good candidate for the treatment of this aggressive B cell lymphoma, especially in combination with autophagy inhibitors or with bortezomib.

Elevated antinuclear antibodies and altered anti-Epstein-Barr virus immune responses.

It has been shown that Epstein-Barr virus (EBV) is able to alter the immune response towards self-antigens and may enhance risk of autoimmune diseases such as systemic lupus erythematosus (SLE) in genetically predisposed individuals. In this study, we evaluated the specific antibody immune response against EBV in patients with anti-nuclear autoantibodies (ANA) in comparison with ANA-negative healthy controls. For this purpose, 92 patients with an high anti-ANA reactivity with or without concomitant extractable nuclear antigen (ENA) or double stranded DNA (dsDNA) positivity were selected and compared with 146 healthy donors. We found that anti-EBV-VCA and EA IgG concentrations were significantly higher in ANA-positive patients in comparison to the controls (VCA P<0.0001 and EA P<0,03) as well as in those ANA-positive patients that showed a concomitant ENA positivity (P=0.0002). Interestingly, elevated anti-EBNA-1 IgG was found in a group of patients who had anti SSA/Ro antibodies. Anti-VCA IgM Abs were more frequently found in those patients with a very high titer of ANA (P=0.06); moreover detection of anti-VCA IgM/IgG in absence of anti-EBNA-1 IgG was more frequent in the patient than in the control group. Both these conditions correlate with a recent EBV infection or reactivation. The data suggest that EBV, particularly during acute infection or in its reactivation phase, could be involved in the ANA and ENA autoantibody formation.