Association between high plasma levels of legumain and cardiovascular events in patients undergoing coronary angiography.

Degradation of vascular extracellular matrix is important in atherosclerosis. Cysteine protease legumain is upregulated in atherosclerotic plaques. We recently reported that plasma legumain levels are high in patients with complex coronary lesions. This study investigated the association between legumain levels and cardiovascular events in 372 patients undergoing coronary angiography. Patients with acute coronary syndrome were excluded. Of the 372 patients, 225 had coronary artery disease (CAD). During a mean follow-up of 7.0 ± 4.3 years, cardiovascular events occured in 62 patients. Compared with 310 patients without events, 62 with events tended to have higher prevalence of complex lesions (15% vs. 10%). Notably, patients with events had higher legumain levels (median 5.51 vs. 4.90 ng/mL, P < 0.01) than those without events. A Kaplan-Meier analysis showed lower event-free survival in patients with legumain > 5.0 ng/mL than in those with ≤ 5.0 ng/mL (P < 0.01). In multivariate Cox regression analysis, legumain level was an independent predictor of cardiovascular events. The hazard ratio for legumain > 5.0 ng/mL for cardiovascular events was 2.18 (95%CI = 1.27-3.77, P < 0.01). Only among 225 patients with CAD, patients with events had higher legumain levels (5.49 vs. 4.73 ng/mL) than without events (P < 0.02). Legumain level was also a predictor of cardiovascular events in patients with CAD. Thus, high plasma legumain levels were associated with an increased risk of cardiovascular events in patients undergoing coronary angiography and those with stable CAD.

Reduced model to predict thrombin and fibrin during thrombosis on collagen/tissue factor under venous flow: Roles of γ'-fibrin and factor XIa.

During thrombosis, thrombin generates fibrin, however fibrin reversibly binds thrombin with low affinity E-domain sites (KD = 2.8 µM) and high affinity γ'-fibrin sites (KD = 0.1 µM). For blood clotting on collagen/tissue factor (1 TF-molecule/µm2) at 200 s-1 wall shear rate, high µM-levels of intraclot thrombin suggest robust prothrombin penetration into clots. Setting intraclot zymogen concentrations to plasma levels (and neglecting cofactor rate limitations) allowed the linearization of 7 Michaelis-Menton reactions between 6 species to simulate intraclot generation of: Factors FXa (via TF/VIIa or FIXa), FIXa (via TF/FVIIa or FXIa), thrombin, fibrin, and FXIa. This reduced model [7 rates, 2 KD's, enzyme half-lives~1 min] predicted the measured clot elution rate of thrombin-antithrombin (TAT) and fragment F1.2 in the presence and absence of the fibrin inhibitor Gly-Pro-Arg-Pro. To predict intraclot fibrin reaching 30 mg/mL by 15 min, the model required fibrinogen penetration into the clot to be strongly diffusion-limited (actual rate/ideal rate = 0.05). The model required free thrombin in the clot (~100 nM) to have an elution half-life of ~2 sec, consistent with measured albumin elution, with most thrombin (>99%) being fibrin-bound. Thrombin-feedback activation of FXIa became prominent and reached 5 pM FXIa at >500 sec in the simulation, consistent with anti-FXIa experiments. In predicting intrathrombus thrombin and fibrin during 15-min microfluidic experiments, the model revealed "cascade amplification" from 30 pM levels of intrinsic tenase to 15 nM prothrombinase to 15 µM thrombin to 90 µM fibrin. Especially useful for multiscale simulation, this reduced model predicts thrombin and fibrin co-regulation during thrombosis under flow.

Identification of novel diagnostic biomarkers for deep venous thrombosis.

The combination of a negative D-dimer and a Wells score can rule out, but not confirm, a diagnosis of deep venous thrombosis (DVT). We aimed to identify new diagnostic biomarkers for DVT and to investigate their relationship with hypercoagulability markers [D-dimer and activated protein C-protein C inhibitor (APC-PCI) complex]. We screened 92 cardiovascular-specific proteins in plasma samples from 45 confirmed DVT patients and 45 age- and sex-matched non-DVT patients selected from a prospective multicentre diagnostic management study (SCORE) by Proseek Multiplex CVDIII96×96 . Plasma levels of 30 proteins were significantly different between DVT and non-DVT patients. After Bonferroni correction, plasma levels of seven proteins: P-selectin, transferrin receptor protein 1, von Willebrand factor, tissue factor pathway inhibitor, osteopontin (OPN), bleomycin hydrolase and ST2 protein remained significantly different. The area under curve (AUC) for these proteins ranged from 0·70 to 0·84. Furthermore, all seven identified proteins were significantly associated with markers of hypercoagulability. A combination of OPN and APC-PCI had the best ability to discriminate DVT from non-DVT patients (AUC = 0·94; sensitivity = 89% and specificity = s84%). In conclusion, we identified multiple proteins associated with markers of hypercoagulability and with a potential to become novel diagnostic biomarkers for DVT.

Transpeptidation-Mediated Assembly of Tripartite Split Green Fluorescent Protein for Label-Free Assay of Sortase Activity.

Transpeptidation of surface proteins catalyzed by the transpeptidase sortase plays a critical role in the infection process of Gram-positive pathogen, and probing sortase activity and screening its inhibitors are of great significance to fundamental biological research and pharmaceutical development, especially novel antivirulence drug design. Herein, we developed a novel fluorescent biosensor to detect sortase activity based on a transpeptidation-triggered assembly of tripartite split green fluorescent protein (split GFP). Peptide P1, composed the 10th ß-sheet of GFP (GFP10) and the sortase A (SrtA) recognition sequence (LPETX), and peptide P2, the 11th ß-sheet of GFP (GFP11) with oligoglycine at N-terminal, were designed and synthesized, respectively. Existence of SrtA enables P1 and P2 to ligate into one peptide, which could spontaneously bind to GFP1-9 (the 1st to 9th ß-sheets of GFP) and assemble into functional GFP. Thus, the sortase-catalyzed transpeptidation can switch on the fluorescence signal of GFP. The method was successfully applied to detect SrtA activity with a low detection limit of 0.16 nM and for its inhibition measurement. Moreover, the feasibility of the proposed assay was further expanded to detect SrtA in human blood and further Gram-positive pathogens analysis in frozen food. Our method, using tripartite split GFP as a readout, is facile, label-free, and sensitive and exhibits great potential as a promising platform for sortase detection and inhibitor screening.

Lipoprotein modifications by gingipains of Porphyromonas gingivalis.

BACKGROUND AND OBJECTIVE: Several studies have shown an association between periodontitis and cardiovascular disease (CVD). Atherosclerosis is the major cause of CVD, and a key event in the development of atherosclerosis is accumulation of lipoproteins within the arterial wall. Bacteria are the primary etiologic agents in periodontitis and Porphyromonas gingivalis is the major pathogen in the disease. Several studies support a role of modified low-density lipoprotein (LDL) in atherogenesis; however, the pathogenic stimuli that induce the changes and the mechanisms by which this occur are unknown. This study aims to identify alterations in plasma lipoproteins induced by the periodontopathic species of bacterium, P. gingivalis, in vitro. MATERIAL AND METHODS: Plasma lipoproteins were isolated from whole blood treated with wild-type and gingipain-mutant (lacking either the Rgp- or Kgp gingipains) P. gingivalis by density/gradient-ultracentrifugation and were studied using 2-dimensional gel electrophoresis followed by matrix-assisted laser desorption/ionization mass spectrometry. Porphyromonas gingivalis-induced lipid peroxidation and antioxidant levels were measured by thiobarbituric acid-reactive substances and antioxidant assay kits, respectively, and lumiaggregometry was used for measurement of reactive oxygen species (ROS) and aggregation. RESULTS: Porphyromonas gingivalis exerted substantial proteolytic effects on the lipoproteins. The Rgp gingipains were responsible for producing 2 apoE fragments, as well as 2 apoB-100 fragments, in LDL, and the Kgp gingipain produced an unidentified fragment in high-density lipoproteins. Porphyromonas gingivalis and its different gingipain variants induced ROS and consumed antioxidants. Both the Rgp and Kgp gingipains were involved in inducing lipid peroxidation. CONCLUSION: Porphyromonas gingivalis has the potential to change the expression of lipoproteins in blood, which may represent a crucial link between periodontitis and CVD.

Plasma Immunoproteasome Predicts Early Hemorrhagic Transformation in Acute Ischemic Stroke Patients.

BACKGROUND AND PURPOSE: Currently, blood biomarkers associated with an increased hemorrhagic transformation (HT) risk remain uncertain. We aimed to determine the significance of immunoproteasome as predictors of early HT in acute ischemic stroke patients. METHODS: This study enrolled 316 patients with ischemic stroke. HT was assessed by computed tomography examination performed on day 5 ± 2 after stroke onset or immediately in case of clinical deterioration (CD). Plasma immunoproteasome subunits low molecular mass peptide 2 (LMP2), multicatalytic endopeptidase complex-like 1 (MECL-1), LMP7, interleukin-1ß (IL1ß), and high-sensitivity C-reactive protein (Hs-CRP) were measured with quantitative sandwich enzyme-linked immunosorbent assay kits. Factors associated with HT were analyzed using a multivariate logistic regression analysis. RESULTS: There were 42 (13.3%, 42 of 316) patients who experienced HT. Compared with those patients without HT, plasma LMP2, MECL-1, LMP7, IL1ß, and Hs-CRP concentrations on admission were significantly increased in patients with subsequent HT (P < .001). These protein concentrations increased with hemorrhage severity. Patients with CD caused by HT had the highest levels of LMP2 (1679.5 [1394.6-136.6] pg/mL), MECL-1 (992.5 [849.7-1075.8] pg/mL), LMP7 (822.6 [748.6-1009.5] pg/mL), IL1ß (113.2 [90.6-194.5] pg/mL), and Hs-CRP (30.0 [12.8-75.6] mg/L) (P < .05). Logistic regression analysis showed cardioembolism, LMP2, MECL-1, and LMP7 as independent predictors of HT (P < .05). Receiver operating characteristic curve analysis demonstrated LMP2 ≥ 988.3 pg/mL, MECL-1 ≥ 584.7 pg/mL, and LMP7 ≥ 509.0 pg/mL as independent factors associated with HT (P < .001). CONCLUSION: Evaluation of plasma levels of immunoproteasome could be helpful in the early prediction of HT in acute ischemic stroke patients.

Effects by periodontitis on pristane-induced arthritis in rats.

BACKGROUND: An infection-immune association of periodontal disease with rheumatoid arthritis has been suggested. This study aimed to investigate the effect of pre-existing periodontitis on the development and the immune/inflammatory response of pristane-induced arthritis. METHODS: We investigated the effect of periodontitis induced by ligature placement and Porphyromonas gingivalis (P. gingivalis) infection, in combination with Fusobacterium nucleatum to promote its colonization, on the development of pristane-induced arthritis (PIA) in rats (Dark Agouti). Disease progression and severity of periodontitis and arthritis was monitored using clinical assessment, micro-computed tomography (micro-CT)/intraoral radiographs, antibody response, the inflammatory markers such as α-1-acid glycoprotein (α-1-AGP) and c-reactive protein (CRP) as well as cytokine multiplex profiling at different time intervals after induction. RESULTS: Experimentally induced periodontitis manifested clinically (P < 0.05) prior to pristane injection and progressed steadily until the end of experiments (15 weeks), as compared to the non-ligated arthritis group. Injection of pristane 8 weeks after periodontitis-induction led to severe arthritis in all rats demonstrating that the severity of arthritis was not affected by the pre-existence of periodontitis. Endpoint analysis showed that 89% of the periodontitis-affected animals were positive for antibodies against arginine gingipain B and furthermore, the plasma antibody levels to a citrullinated P. gingivalis peptidylarginine deiminase (PPAD) peptide (denoted CPP3) were significantly (P < 0.05) higher in periodontitis rats with PIA. Additionally, there was a trend towards increased pro-inflammatory and anti-inflammatory cytokine levels, and increased α-1-AGP levels in plasma from periodontitis-challenged PIA rats. CONCLUSIONS: Pre-existence of periodontitis induced antibodies against citrullinated peptide derived from PPAD in rats with PIA. However, there were no differences in the development or severity of PIA between periodontitis challenged and periodontitis free rats.

Role of legumain in metabolic dysfunction, diagnosis, and prognosis of patients with atherosclerosis.

BACKGROUND: The purpose of this study was to investigate the role of legumain in metabolic dysfunction, diagnosis, and prognosis in patients with atherosclerosis. METHODS: Plasma levels of legumain from patients with atherosclerosis (n = 320) and healthy controls (n = 320), expression of legumain in atheromatous plaque and secreted from monocyte-derived macrophages were measured using enzyme-linked-immunosorbent assay, reverse transcription-polymerase chain reaction, Western blot, immunohistochemistry, and fluorescence. RESULTS: Data demonstrated that atherosclerotic patients had higher plasma level of legumain than healthy controls, which was a diagnostic and prognostic marker and corrected with the degree of atherosclerosis. It found that atheromatous plaque and endothelial cell had higher legumain expression than non-atherosclerotic arteries (controls). Legumain showed significantly increased secretion from pro-inflammatory M1 compared to pro-resolving M2 macrophages during monocyte-derived macrophages, which was localized to structures resembling foam cells. CONCLUSION: In conclusion, our data indicate that legumain expression is upregulated in both plasma and plaques of patients with atherosclerosis, which is associated with metabolic dysfunction of endothelial cell and might be a diagnostic and prognostic marker of atherosclerosis.

Varying allergen composition and content affects the in vivo allergenic activity of commercial Dermatophagoides pteronyssinus extracts.

BACKGROUND: Diagnosis and immunotherapy of house-dust mite (HDM) allergy is still based on natural allergen extracts. The aim of this study was to analyze commercially available Dermatophagoides pteronyssinus extracts from different manufacturers regarding allergen composition and content and whether variations may affect their allergenic activity. METHODS: Antibodies specific for several D. pteronyssinus allergens (Der p 1, 2, 5, 7, 10 and 21) were used to analyze extracts from 10 different manufacturers by immunoblotting. Sandwich ELISAs were used to quantify Der p 1 and Der p 2 in the extracts. Mite-allergic patients (n = 45) were skin-tested with the extracts and tested for immunoglobulin E (IgE) reactivity to a panel of 10 mite allergens (Der p 1, 2, 4, 5, 7, 8, 10, 14, 20 and 21) by dot blot. RESULTS: Only Der p 1 and Der p 2 were detected in all extracts but their concentrations and ratios showed high variability (Der p 1: 6.0-40.8 µg ml(-1); Der p 2: 1.7-45.0 µg ml(-1)). At least 1 out of 4 allergens (i.e. Der p 5, 7, 10 and 21) was not detected in 8 of the studied extracts. Mite-allergic subjects showed different IgE reactivity profiles to the individual mite allergens, the extracts showed different allergenic activity in skin-prick tests and false-negative results. CONCLUSIONS: Commercially available D. pteronyssinus extracts lack important allergens, show great variability regarding allergen composition and content and some gave false-negative diagnostic test results in certain patients.

A universal immuno-PCR platform for comparative and ultrasensitive quantification of dual affinity-tagged proteins in complex matrices.

Protein detection in complex biological fluids and matrices has become a widely diversified field utilizing a number of different technologies. The quantification of target proteins in complex media such as serum remains a challenge for most technologies such as mass spectrometry, ELISA and western blot. Quantitative Immuno-PCR has been heavily used for antigen detection in immunoassays, but minimally so for quantifying affinity-tagged proteins expressed or circulating in complex matrices--despite its high sensitivity and robustness--because it suffers from detrimental background effects arising from its extreme detection power. We report the development of a universal qIPCR-based platform for the reproducible detection of dual affinity-tagged protein analytes in crude complex matrices such as serum and cell culture media or lysates. The system uses a couple of high-affinity antibodies against two affinity tags (GFP and HA) for the detection of dual-tagged proteins. The dual-tagged analyte is immuno-captured by one of its tags, while the second tag is bound by a detection device consisting of a new kind of self-assembled antibody-DNA conjugate. The new qIPCR platform enabled picomolar quantification of dual-tagged sortase in crude serum in 4 h including the PCR step.

The performance of a component-based allergen microarray for the diagnosis of kiwifruit allergy.

BACKGROUND: Allergy to kiwifruit is increasingly reported across Europe. Currently, the reliability of its diagnosis by the measurement of allergen-specific IgE with extracts or by skin testing with fresh fruits is unsatisfying. OBJECTIVE: To evaluate the usefulness of a component-based allergen microarray for the diagnosis of kiwifruit allergy in a large group of patients. METHODS: With an allergen microarray, we measured specific IgE and IgG4 levels to a panel of nine kiwifruit allergens in sera of 237 individuals with kiwifruit allergy. Sera from 198 allergic patients without kiwifruit allergy served as controls. Furthermore, we determined the extent of sensitization to latex. RESULTS: The panel of kiwifruit allergens showed a diagnostic sensitivity of 66%, a specificity of 56% and a positive predictive value of 73%. Sera from kiwifruit-allergic patients contained significantly more frequently Act d 1-specific IgE than sera from control patients. Furthermore, 51% of the positive sera contained IgE directed to a single allergen, namely Act d 1 (45%), Act d 9 (27%) or Act d 7 (13%). Within the control group, 36% sera recognized a single allergen. Out of those, 48% were positive to the cross-reactive glycoallergen Act d 7, 43% to the profilin Act d 9 and only 5% to Act d 1. Allergen-specific IgG4 levels did not differ between kiwifruit-allergic and -tolerant patients. Kiwifruit- and latex-allergic patients contained Hev b 11-specific IgE significantly more frequently than latex-allergic patients without kiwifruit allergy. CONCLUSIONS: Act d 1 can be considered a marker allergen for genuine sensitization to kiwifruit. We demonstrated that a component-based kiwifruit allergen microarray would improve the prognostic value of in vitro diagnostic tests.

Genotyping of acute hepatitis a virus isolates from China, 2003-2008.

Hepatitis A virus (HAV) is usually transmitted by an oral-fecal route and is prevalent not only in developing countries but also in developed countries. In the present study, the phylogenetic characterization of the VP1/2A junction region (321 nucleotides) of China HAV isolates was examined. Anti-HAV IgM-positive serum samples were collected from 8 provinces, including 20 cities or counties in China from 2003 to 2008; 337 isolates from 406 HAV patients' serum samples were amplified by RT-PCR, sequenced at the VP1/2A junction region and aligned with the published sequences from GenBank to establish phylogenetic analysis. All China HAV isolates in this study belonged to genotype I, with 98.8% (333/337) of samples clustering in sub-genotype IA and 1.2% (4/337) in sub-genotype IB. In addition, sub-genotype IA isolates clustered into four groups (92.7-100% nucleotide identity), and the samples collected from all China HAV isolates in this investigation showed 87.5-100% nucleotide identity, but the amino acids in this region were more conserved (95.2-100% identity). Few unique amino acid changes could be deduced (VP1-253: Glu → Gly; 2A-34: Pro → Ala; 2A-33: Leu → Phe). Genetically identical or similar HAV strains existed in some investigated areas in China during different years, suggesting that an indigenous strain has been circulating in those regions. This report provides new data on the genetic relatedness and molecular epidemiology of HAV isolates from China as well as the distribution of sub-genotype IA and IB in this part of the world.

Plasma EVs Display Antigen-Presenting Characteristics in Patients With Allergic Rhinitis and Promote Differentiation of Th2 Cells.

Background: Allergic rhinitis (AR) is characterized by IgE-mediated mucosa response after exposure to allergens. Extracellular vesicles (EVs) are nano-size vesicles containing biological cargos for intercellular communications. However, the role of plasma EVs in pathogenesis of AR remains largely unknown. Methods: Plasma EVs from patients with AR were isolated, quantified, and characterized. The expression of Der p 1 and antigen-presenting molecules on EVs was determined by Western blot, flow cytometry, or ELISA. PKH26- and CFSE (carboxyfluorescein succinimidyl ester)-stained AR-EVs were used to determine the uptake of EVs by CD4+T cells and their effects on CD4+T cell proliferation, respectively. Results: Plasma EVs in healthy control (HC) and AR patients were similar in the concentration of particles, expression for specific EV markers, and both had structural lipid bilayer. However, the levels of Der p 1 on plasma EVs from both mild and moderate-severe AR patients were significantly higher than that on HC. The levels of antigen-presenting molecules on plasma EVs were similar from three subjects. Moreover, levels of Der p 1 on EVs in plasma, but not nasal secretion, were significantly associated with the symptom score of AR patients and level of plasma IL-13. Additionally, plasma EVs from patients with AR promoted the development of Th2 cells, while no effect was found on CD4+ T-cell proliferation. Conclusions: Plasma EVs derived from patients with AR exhibited antigen-presenting characteristics and promoted differentiation of Th2 cells, thus providing novel understanding of the pathogenesis of AR.

Increased activity of procoagulant factors in patients with small cell lung cancer.

Small cell lung cancer (SCLC) patients have augmented risk of developing venous thromboembolism, but the mechanisms triggering this burden on the coagulation system remain to be understood. Recently, cell-derived microparticles carrying procoagulant phospholipids (PPL) and tissue factor (TF) in their membrane have attracted attention as possible contributors to the thrombogenic processes in cancers. The aims of this study were to assess the coagulation activity of platelet-poor plasma from 38 SCLC patients and to provide a detailed procoagulant profiling of small and large extracellular vesicles (EVs) isolated from these patients at the time of diagnosis, during and after treatment compared to 20 healthy controls. Hypercoagulability testing was performed by thrombin generation (TG), procoagulant phospholipid (PPL), TF activity, Protein C, FVIII activity and cell-free deoxyribonucleic acid (cfDNA), a surrogate measure for neutrophil extracellular traps (NETs). Our results revealed a coagulation activity that is significantly increased in the plasma of SCLC patients when compared to age-related healthy controls, but no substantial changes in coagulation activity during treatment and at follow-up. Although EVs in the patients revealed an increased PPL and TF activity compared with the controls, the TG profiles of EVs added to a standard plasma were similar for patients and controls. Finally, we found no differences in the coagulation profile of patients who developed VTE to those who did not, i.e. the tests could not predict VTE. In conclusion, we found that SCLC patients display an overall increased coagulation activity at time of diagnosis and during the disease, which may contribute to their higher risk of VTE.

Serum Legumain Is Associated with Peripheral Artery Disease in Patients with Type 2 Diabetes.

BACKGROUND: Legumain is related to carotid atherosclerotic plaques and may be a new biomarker of carotid atherosclerosis. However, the association between legumain and peripheral artery disease (PAD) of lower extremity has been less studied. This study is aimed at exploring the potential link between legumain and PAD in patients with type 2 diabetes mellitus (T2DM). METHODS: A cross-sectional study was conducted on 483 hospitalized T2DM patients. The serum legumain level was measured by a sandwich enzyme-linked immunosorbent assay. PAD was evaluated by color Doppler sonography. The association between legumain and PAD was tested by logistic regression. The predictive power of legumain for PAD was evaluated with the receiver-operating-characteristic (ROC) curve. RESULTS: Overall, 201 (41.6%) patients suffered from PAD. Patients with PAD had significantly higher serum legumain level than those without PAD [11.9 (6.3, 17.9) µg/L vs. 7.6 (3.2, 14.2) µg/L, p < 0.001]. Logistic regression showed that a higher serum legumain level was independently associated with a greater risk of PAD in T2DM patients [adjusted odds ratio (aOR): 1.03; 95% confidence interval (CI): 1.01-1.06]. The area under the ROC curve was 0.634 (95% CI, 0.585 to 0.684). CONCLUSION: High serum legumain level was significantly correlated with an increased risk of PAD in T2DM patients.

Detection of the Sm31 antigen in sera of Schistosoma mansoni- infected patients from a low endemic area.

Schistosoma mansoni cathepsin B (Sm31) is a major antigen from adult worms that circulates in the blood of infected patients (Li et al., Parasitol Res 1996; 82: 14-18). An analysis of the Sm31 sequence (Klinkert et al., Mol Biochem Parasitol 1989; 33: 113-122) allowed the prediction of seven hydrophilic regions that were confirmed to be exposed on the surface of a 3D model of Sm31; the species specificity of these regions was checked using BLAST analysis. The corresponding peptides were chemically synthesized in polymerazible forms using the t-Boc technique. Rabbits developed a high humoral response against these peptides as tested by a multiple antigen blot assay; it recognized native Sm31 in crude S. mansoni extracts and as circulating antigen in sera of S. mansoni-infected patients by western blot. Relevant antigenic determinants were located at the N- and C-terminus sequences. Antibodies against these regions recognized the native enzyme in an ELISA-like assay called cysteine protease immuno assay in which the immunocaptured enzyme was revealed by the intrinsic cathepsin B hydrolytic activity of Sm31. The method successfully and specifically detected Sm31 in sera of infected individuals, most of them (83.3%) with light infections, offering a rationale for the development of parasite enzyme capture assays using anti-synthetic peptide antibodies for possible use in the diagnosis of schistoso,iasis.

Indication of participation of caspase-2 and caspase-5 in mechanisms of human cervical malignancy.

INTRODUCTION: When apoptosis is disrupted, the transformed cells can survive, proliferate, and evolve into a malignancy. The strictly conserved caspase genes and the reliable experimental data clearly show that some caspases play a crucial role in apoptosis even if some of them have no apoptotic activity and others exhibit both apoptotic and nonapoptotic properties. Although caspase-2 belongs to initiator caspases, its normal role remains unclear. Experimental studies have shown that it is primarily necessary for the execution of apoptosis in mutagenic cells. Human caspase-5 is classified as an inflammatory caspase, although its substrate has not been identified yet. In this research, the activities of caspase-2 and caspase-5 have been estimated during the progression of human cervical malignancy. METHODS: The experimental material includes human cervical tissue samples (normal and pathological) and blood serum samples of the corresponding tissue donors, where enzyme activities have been measured colorimetrically. RESULTS: Both caspases' activities showed the highest increase, statistically significant (P < 0.01, by t test) compared with the controls, in the low-grade squamous intraepithelial lesion tissues. Caspase-2 of all pathological tissues was proved more active than the controls. Serum caspases' activities were significantly lower than those of the tissues. Serum caspase-2's activity in patients with low-grade squamous intraepithelial lesion stage showed no statistically significant increase compared with the controls. Serum caspase-5's activity of all patients with malignancy stages was presented elevated, whereas that of the serum of patients with cervical cancer had the highest activity (P < 0.01, by t test). CONCLUSIONS: The changes of caspase-2 and caspase-5 activities could be indicative of their involvement in the cervical malignancy mechanisms.

Differences in cysteine peptidases-like activity in sera of patients with breast cancer.

BACKGROUND: The key role in carcinogenesis with destruction of the extracellular matrix is played by proteases released by invasive cancer cells. Cysteine peptidases, such as cathepsin B and L, take an important role in cancer progression and metastasis. OBJECTIVES: Cysteine peptidase-like activity (CPA) in sera of patients with breast cancer at different stages of disease and the influence of genetic predisposition associated with BRCA-1 gene mutations were analysed. METHODS: CPA in serum was determined with the spectrofluorometric technique using Z-Phe-Arg-AMC as a substrate. Determination was carried out in 111 breast cancer patients in comparison to a control group of 50 healthy subjects. RESULTS: The highest CPA was found in breast cancer patients with a hereditary predisposition bearing BRCA1 gene mutations, and the lowest activity was found in patients who had a tumour surgically removed and before adjuvant therapy. The differences in the activities between control group and cancer groups were statistically significant (p< 0.05), except from group of cancer patients in complete remission (p< 0.52). CONCLUSIONS: Serum CPA in patients with breast cancer differs depending on the cancer stage and treatment methods. Our study demonstrate the correlation between BRCA-1 gene mutations and the increased level of CPA.

Legumain in Acute Coronary Syndromes: A Substudy of the PLATO (Platelet Inhibition and Patient Outcomes) Trial.

Background The cysteine protease legumain is increased in patients with atherosclerosis, but its causal role in atherogenesis and cardiovascular disease is still unclear. The aim of the study was to investigate the association of legumain with clinical outcome in a large cohort of patients with acute coronary syndrome. Methods and Results Serum levels of legumain were analyzed in 4883 patients with acute coronary syndrome from a substudy of the PLATO (Platelet Inhibition and Patient Outcomes) trial. Levels were analyzed at admission and after 1 month follow-up. Associations between legumain and a composite of cardiovascular death, spontaneous myocardial infarction or stroke, and its individual components were assessed by multivariable Cox regression analyses. At baseline, a 50% increase in legumain level was associated with a hazard ratio (HR) of 1.13 (95% CI, 1.04-1.21), P=0.0018, for the primary composite end point, adjusted for randomized treatment. The association remained significant after adjustment for important clinical and demographic variables (HR, 1.10; 95% CI, 1.02-1.19; P=0.013) but not in the fully adjusted model. Legumain levels at 1 month were not associated with the composite end point but were negatively associated with stroke (HR, 0.62; 95% CI, 0.44-0.88; P=0.0069), including in the fully adjusted model (HR, 0.57; 95% CI, 0.37-0.88; P=0.0114). Conclusions Baseline legumain was associated with the primary outcome in patients with acute coronary syndrome, but not in the fully adjusted model. The association between high levels of legumain at 1 month and decreased occurrence of stroke could be of interest from a mechanistic point of view, illustrating the potential dual role of legumain during atherogenesis and acute coronary syndrome. Registration URL: https://www.clini​caltr​ials.gov; Unique identifier: NCT00391872.