Elli F. Kamper

CD40/CD40L signaling and its implication in health and disease.

CD40, a transmembrane receptor of the tumor necrosis factor gene superfamily is expressed on a variety of cells, such as monocytes, B‐cells, antigen presenting cells, endothelial, smooth muscle cells, and fibroblasts. The interaction between CD40 and CD40 ligand (CD40L) enhances the expression of cytokines, chemokines, matrix metalloproteinases, growth factors, and adhesion molecules, mainly through the stimulation of nuclear factor kappa B. The aim of this review is to summarize the molecular and cellular characteristics of CD40 and CD40L, the mechanisms that regulate their expression, the cellular responses they stimulate and finally their implication in the pathophysiology of inflammatory and autoimmune diseases.

The pattern of inflammatory/anti-inflammatory cytokines and chemokines in type 1 diabetic patients over time

Abstract Aims. To evaluate the profile of pro- and anti-inflammatory cytokines in type 1 diabetes mellitus (T1DM) and the way they are connected in co-regulated networks and determine whether disease duration influences their pattern. Methods. Plasma levels of 20 cytokines and soluble CD40 (sCD40) from 44 uncomplicated patients and 22 healthy controls (HCs) were measured using enzyme-linked immunosorbent assay (ELISA) and protein array technology. Results. Patients showed significantly higher levels of sCD40, IL-1a, IL-2, IL-4, IL-5, IL-10, granulocyte-macrophage colony-stimulating factor (GM-CSF), macrophage inflammatory protein (MIP)-1a, MIP-1b, regulated on activation normal T cell expressed and secreted (RANTES), matrix metalloproteinase (MMP)-9, and a trend to higher IL-6 than did HCs. RANTES and sCD40 discriminated significantly between diabetics and HCs. In patients with disease duration >6 months, cytokines were organized in two clusters mainly regulated by Th17 and Th1/Th2 cells respectively, while in those with disease duration ≤6 months a set of Th1-cytokines was separated apart from the second cluster. Monocyte chemotactic protein (MCP)-1 was revealed as the most discriminant factor between patients with disease duration of more than and less than 6 months. Conclusions. A parallel elevation of both inflammatory and anti-inflammatory cytokines was observed in patients compared with HCs. In T1DM patients with disease duration ≤6 months, Th1-cytokines were organized on a separate cluster, suggesting a possible role of Th1 cells in the progress of beta-cell destruction during the first period of the disease.

Sex differences in oxidant/antioxidant balance under a chronic mild stress regime.

The deterioration of homeostasis between oxidant/antioxidant species may represent an important mechanism linking psychological stress to cardiovascular risk despite the many sex differences in stress responsiveness. The goal of the present study was to investigate the influence of chronic mild stress (CMS), a widely accepted animal model of depression, on oxidative homeostasis-allostasis markers and sICAM-1, a marker of endothelial injury, in the serum of Wistar rats, by taking into account the effect of sex. After six weeks of exposure to mild unpredictable environmental stressors, both male and female rat groups displayed typical changes in hedonic status (anhedonia), which is a core symptom of human depression. Control female rats had higher (nitrite and nitrate) NOx, lower malondealdehyde (MDA) levels with lower activity of antioxidant enzymes and sICAM-1 levels than did control males. CMS induced oxidant/antioxidant responses in both sexes. Females tended to increase their nitric oxide (NO) levels further, while MDA levels did not reach those of males, thus retaining significantly higher NO bioavailability than in males. Concerning the antioxidant enzymes, CMS-females exhibited significantly higher glutathione peroxidase (GPx) activity and lower glutathione reductase (GR) and superoxide dismutase (SOD) activity compared to CMS-males. The CMS response in females was accompanied by lower sICAM-1 levels than in males, suggesting lower endothelial injury. In conclusion, the results of the present study showed that CMS induces different oxidative stress and compensatory responses in both sexes probably due to differences in the mechanisms regulating oxidant/antioxidant pathways.

Oxidative stress and adhesion molecules in children with type 1 diabetes mellitus: a possible link.

Objective:  To examine whether oxidative stress parameters were correlated with adhesion molecules derived from endothelial/platelet activation in a group of juveniles with type 1 diabetes mellitus (T1DM).

Serum levels of tetranectin, intercellular adhesion molecule-1 and interleukin-10 in B-chronic lymphocytic leukemia

BACKGROUND AND OBJECTIVE The fibrinolytic regulator tetranectin (TN), in association with the circulating intercellular adhesive molecule-1 (cICAM-1) and interleukin -10 (IL-10), may be involved in the metastatic cascade of B-chronic lymphocytic leukemia (B-CLL). Our aim was to investigate the potential usefulness of these molecules as prognostic markers in B-CLL. DESIGN AND METHODS Therefore, TN, cICAM-1, and IL-10 were assessed (ELISA) in the serum of 53 B-CLL patients, classified in Binet A, B, and C stages in comparison with those in 45 healthy subjects (HS). RESULTS TN was significantly lower in B-CLL patients than in HS (9.63 [8.75-11.51] mg/L, 13.75 [12.56-14.64] ng/mL, respectively, p<10(-5)), being lower (p = 0.05) in B and C stage patients (subgroup B+C) than in A stage ones (subgroup A). cICAM-1 levels were significantly higher in B-CLL patients than in HS (475.86 [355.86-593.79] ng/mL vs. 225.62 [118.49-312.83] ng/mL, respectively, p<10(-5)) with a tendency for higher levels in subgroup B+C than in subgroup A. A significant correlation of cICAM-1 with lactate dehydrogenase (LDH) (r(s) = 0.532, p = 0.049), and a significant increase in cICAM-1 in B-CLL with diffuse bone marrow infiltration (BMI) compared to that in B-CLL with nondiffuse BMI (624.48 [557.24-726.55] ng/mL vs. 480.34 [368.96-590.34] ng/mL, respectively, p = 0.0172) were found. A significant negative correlation between TN and cICAM-1 (r = -0.5017, p = 0.0001) was observed. IL-10 was detected in all B-CLL patients and in no HS (7.37 [5.30-10.55] pg/mL), being higher (p = 0.0153) in C than in A stage patients. A significant correlation of IL-10 with TN and cICAM-1 in subgroup B+C (r(s) = -0.659 [p = 0.014] and r = 0.679 [p = 0.011], respectively) was found. CONCLUSIONS The abovementioned findings and good performance characteristics of TN and cICAM-1 in B-CLL suggest the potential usefulness of these adhesive/recognition molecules as prognostic markers in B-CLL. The implication of these molecules along with IL-10 in the disease process deserves further study.

Tetranectin levels in patients with acute myocardial infarction and their alterations during thrombolytic treatment

Tetranectin (TN), a new regulator of fibrinolysis, was studied in the plasma of 60 patients with acute myocardial infarction (AMI) and 30 healthy subjects (HS), in relation to D-dimer (DD) and α2-plasmin inhibitor (α2-PI), to investigate its possible involvement in the pathophysiology of AMI. Thirty patients underwent thrombolytic treatment with fibrin-specific plasminogen activator (rt-PA) (group A); the other 30 patients, according to the exclusion criteria, were conventionally treated (group B). Twenty of the thrombolysized patients established early recanalization (subgroup A1), while 10 failed to respond to thrombolytic treatment (subgroup A2). Median (interquartile range), baseline plasma TN levels were lower in AMI patients compared to HS [8·27 (2·75) mg/L versus 12·1 (0·55) mg/L, P <10−6]. In subgroup A1, TN increased at the end of rt-PA infusion and returned to the baseline levels 12 h later. A positive association between DD and TN release (3 h level minus baseline level) was found (r s = 0·48, P = 0·03) in subgroup A1. No significant alterations of TN levels were observed during therapy in subgroup A2 and group B. TN, DD and α2-PI concentrations in group B remained relatively constant during the study period. This study provides evidence of a significant decrease of TN levels in AMI patients compared to healthy subjects and of a remarkable difference in the evolution of TN levels during thrombolytic treatment with rt-PA between recanalized and non-recanalized AMI patients. Thus, an involvement of TN in the formation and dissolution of fibrin clot in AMI patients is worthy of further investigation.

Modulation of synaptosomal plasma membrane-bound enzyme activity through the perturbation of plasma membrane lipid structure by bupivacaine

We investigated modulations of lipid dynamics and lipid-protein interactions of rat brain synaptosomal plasma membrane (SPM) as one of the possible mechanisms by which the local anesthetic bupivacaine (BPV) has an adverse effect on nerve cell function, with SPM-bound enzyme activity used as a functional probe. The kinetics of BPV impact on the activity of the endoenzymes Ca2+/Mg2+-stimulated ATPase and Na+/K+-stimulated ATPase and the active concentrations of the drug were relevant to those that produce biphasic systemic toxicity. Arrhenius plots of these enzymes showed a transition temperature of 26.6 +/- 1.8[degree sign]C and 24.5 +/- 1.2[degree sign]C (mean +/- SD), respectively, in control SPM, which shifted to 17.1 +/- 0.95[degree sign]C (P < 0.01) and 18.2 +/- 0.85[degree sign]C (P < 0.05) in SPM treated with 10-5 M BPV. The Hill coefficients for the allosteric inhibition of Ca2+/Mg2+-stimulated ATPase by Na+ and Na+/K+-stimulated ATPase by fluoride decreased from 1.73 +/- 0.20 and 1.95 +/- 0.25, respectively, in controls to 0.92 +/- 0.09 (P < 0.001) and 1.09 +/- 0.11 (P < 0.001) in the presence of 10-5 M BPV. The fluidity perturbation in the microenvironment of the ectoenzyme acetylcholinesterase was observed only at 5 x 10-3 M BPV, as confirmed by the disparity in transition temperature between the controls (22.3 +/- 1.2[degree sign]C) and the BPV-treated SPM (17.5 +/- 0.8[degree sign]C, P < 0.01) and that in the Hill coefficient in the two groups: 2.15 +/- 0.24 and 0.97 +/- 0.12 (P < 0.001), respectively. Implications: We propose that under physiological conditions, the neutral and protonated forms of local anesthetics can affect nerve cell function through the asymmetric perturbation of the membrane lipid structure, accompanied by synaptosomal plasma membrane-bound enzyme dysfunction. (Anesth Analg 1997;85:1337-43)

Alterations in biomarkers of endothelial function following on-pump coronary artery revascularization.

Background: Cardiopulmonary bypass (CPB) has been associated with activation and injury of endothelial cells, probably responsible for the systemic inflammatory response syndrome (SIRS) taking place in these patients. Methods: We measured plasma concentrations of soluble P‐selectin (sP‐s), E‐selectin (sE‐s), tetranectin (TN), vonWillebrand factor (vWF) levels, and angiotensin‐converting enzyme (ACE) activity in 31 adult patients undergoing elective coronary artery bypass grafting, just before and up to three days after surgery, and in 25 healthy volunteers. Results: Patients showed higher plasma sP‐s and sE‐s and ACE concentrations, just before surgery, but significantly lower TN levels, compared with controls. During the first three postoperative days (PD), the concentration of each of the molecules followed a different and independent pattern, although in the third PD, the levels of sP‐s, sE‐s and ACE were higher and those of vWF and TN lower, compared with the preoperative ones. However, patients had higher sP‐s (P=0.06), sE‐s (P=0.07), and vWF (P=0.005), but lower TN concentrations (P=0.02) on the third PD compared with controls. Conclusions: CPB is characterised by pronounced changes in plasma sP‐s, sE‐s, TN, vWF levels, and ACE activity, which are associated with significant alteration in the intra‐ and early postoperative endothelial function observed in open heart surgery. J. Clin. Lab. Anal. 24:389–398, 2010.

Comparative study of tetranectin levels in serum and synovial fluid of patients with rheumatoid arthritis, seronegative spondylarthritis and osteoarthritis

Tetranectin (TN) was assessed in paired synovial fluid (SF) and serum (S) samples from 27 patients with rheumatoid arthritis (RA), 23 with seronegative spondylarthritis (SSA) and 22 with osteoarthritis (OA). RA patients had a stronger correlation between serum and SF TN and a higher SF/S TN ratio than did SSA and OA patients. Moreover, the SF/S TN ratio exceeded 1 in most RA patients but not in SSA and OA patients, indicating the possibility of intraarticular TN synthesis in RA. A strong correlation of serum and SF TN with known inflammatory markers was observed in RA. The TN/proteinase inhibitors (PIs: α1-antitrypsin, α2-macroglobulin molar ratio in SF was lower in RA and SSA patients to a statistically significant degree than in OA patients. In RA, in contrast to SSA and OA, this ratio correlated positively with the SF interleukin-8 (IL-8), responsible for neutrophil recruitment and degranulation and negatively with erythrocyte sedimentation rate, serum C-reactive protein and fibrinogen, known markers of disease activity. In conclusion, patients with RA showed lower serum TN levels, a higher SF/S TN ratio and a lower SF TN/PI molar ratio than did SSA and OA patients, suggesting the implication of TN in the impaired regulation of fibrinolysis associated with the inflammatory process.

Increased serum type I interferon activity in organ-specific autoimmune disorders: clinical, imaging, and serological associations

Background: Activation of the type I interferon (IFN) pathway has been implicated in the pathogenesis of systemic autoimmune disorders but its role in the pathogenesis of organ-specific autoimmunity is limited. We tested the hypothesis that endogenous expression of type I IFN functional activity contributes to the pathogenesis of autoimmune thyroid disease (ATD) and type I diabetes (T1DM). Methods: We studied 39 patients with ATD and 39 age and sex matched controls along with 88 T1DM patients and 46 healthy matched controls respectively. Available clinical and serological parameters were recorded by chart review, and thyroid ultrasound was performed in 17 ATD patients. Type I IFN serum activity was determined in all subjects using a reporter cell assay. The rs1990760 SNP of the interferon-induced helicase 1 gene was genotyped in ATD patients. Results: Serum type I IFN activity was increased in patients with ATD and T1DM compared to controls (p-values: 0.002 and 0.04, respectively). ATD patients with high type I IFN serum activity had increased prevalence of antibodies against thyroglobulin (anti-Tg) and cardiopulmonary manifestations compared to those with low IFN activity. Additionally, the presence of micronodules on thyroid ultrasound was associated with higher type I IFN levels. In patients with T1DM, high IFN levels were associated with increased apolipoprotein-B levels. Conclusion: Serum type I IFN activity is increased in ATD and T1DM and is associated with specific clinical, serological, and imaging features. These findings may implicate type I IFN pathway in the pathogenesis of specific features of organ-specific autoimmunity.