The liberated domain I of urokinase plasminogen activator receptor – a new tumour marker in small cell lung cancer

The prognosis of small cell lung cancer (SCLC) remains poor with a 5‐year survival rate of 4–6%. In non‐small cell lung cancer (NSCLC), high levels of intact and cleaved forms of the receptor for urokinase plasminogen activator (uPAR) are significantly associated with short overall survival. Our aim was therefore to determine the prognostic value of the different uPAR forms in blood from SCLC patients. Serum samples from 92 treatment naive SCLC patients were analysed. Intact uPAR, uPAR(I–III), intact and cleaved uPAR, uPAR(I–III) + uPAR(II–III) and the liberated domain I, uPAR(I) were measured using time‐resolved fluorescence immunoassays (TR‐FIA 1–3). Assessment of association of the uPAR forms to overall survival (OS) was done using Cox regression analysis adjusted for clinical covariates [age, gender, stage, lactate dehydrogenase (LDH), WHO performance status (PS)]. Multivariate survival analysis demonstrated that high levels of uPAR(I) were significantly (p = 0.009) associated with short overall survival (OS). Patients with uPAR(I) levels above the second tertile had a hazard ratio (HR) of 1.9 (95% confidence interval (CI): 1.1–3.3), compared to patients with levels below the first tertile. High serum uPAR(I) levels are associated with short OS in SCLC patient, independent of LDH and PS.     

Sensitive and rapid immunoassays for Salmonella enteritidis.

In order to develop more sensitive, specific, and rapid immunoassays to detect Salmonella enteritidis in food supplies, we have applied various approaches by using several different antibody preparations. Utilizing ELISA in both a plate and immunodot assay, we employed (i) a polycolonal rabbit antiserum to a boiled suspension of the organism; (ii) a monoclonal antibody to the cell surface of the bacterium; and (iii) mouse antisera to two oligosaccharides each containing the rare sugar tyvelose, and exhibited by S. enteritidis, a member of the group D salmonellae. We showed that the polyclonal antiserum and monoclonal antibody IG-10 to the cell surface could specifically detect from 10(2) to 10(3) organisms in a 10-microl sample in the plate and immunodot assay. Both assays are read in 4-5 hr. Further, in the mice immunized to the trisaccharide, (alpha-D-galactose-alpha-tyvelose-alpha-D-mannose), as well as those mice immunized to the tetrasaccharide, (alpha-D-galactose-alpha-tyvelose-alpha-D-mannose-alpha-L-rhamnose), specificity to tyvelose was determined by inhibition studies. The inhibitors of the antisera to the trisaccharide included the single sugar tyvelose conjugated to bovine serum albumin (BSA), a tetrasaccharide in which tyvelose is excluded, but contains alpha-D-galactose, alpha-ascarose, alpha-D-mannose, and alpha-L-rhamnose (conjugated to BSA), and others. The inhibition studies suggest that the mouse antisera are specific for tyvelose and also contain antibodies for mannose and rhamnose. The antibodies that have been made to the unique sugar tyvelose should improve the specificity in assays for S. enteritidis.     

Barriers to successful transplantation of the sensitized patient

Antibody present in the transplant recipient that yields a positive crossmatch with donor cells has long been considered a contraindication and an absolute barrier to transplantation. However, improved methods of antibody detection and characterization have shown that some reactivity with donor cells may be inconsequential to transplantation. Furthermore, the development of treatment protocols to downregulate the humoral immune response has shown that the barrier of sensitization can be overcome, permitting safe transplantation of the sensitized patient. Both of these factors have not only led to an increased rate of transplantation among sensitized patients but have also added to our understanding of the immune response and immune regulation. Here, we review the characteristics of antibodies believed to be relevant to transplant success and the various approaches to dealing with them.     

Evaluation of the performance of 5 commercialized enzyme immunoassays for the detection of Taenia solium antibodies and for the diagnosis of neurocysticercosis

This study aimed to evaluate 5 enzyme immunoassays for detecting human antibodies against Taenia solium in human serum and for the diagnosis of neurocysticercosis (NCC): DRG™, RIDASCREEN™, NOVATECH™, CYPRESS™, and IVD™. A collection of 114 reference serum samples were used. All sera were tested both by ELISA and by an immunoblot method (enzyme-linked immunoelectrotransfer blot [EITB]). When compared with EITB, the Ridascreen™ test had the best positive concordance rate (85.1-91.2%) and the NovaLisa test™ showed the optimal negative concordance rate (93.7-95.6%). All tests had a sensitivity under 72% and a specificity above 60%. The best sensitivity was obtained using Ridascreen™ test (71.4%). An optimal specificity was achieved by the NovaLisa test™. T. solium-positive sera all cross-reacted with E. granulosus positive samples. In the commercial assays evaluated here, the most appropriate ELISA test for screening may be the Ridascreen™ assay. Antibody detection seems to be not appropriate for NCC diagnosis because of its overall lack of sensitivity.     

Comparison of four digoxin immunoassays with respect to interference from digoxin-like immunoreactive factors

Objectives: Comparison of a new monoclonal digoxin assay with three polyclonal digoxin assays for their cross-reactivity to digoxinlike immunoreactive factors (DLIF) and digoxin metabolites.

Design and Methods: Sixty-:six nondigitalized patient samples from 5 different groups: neonates, women in 3rd trimester pregnancy, and patients with liver or renal diseases, or undergoing organ transplants, and 139 samples from digoxin-treated patients of 4 categories (hospital sick, liver, renal, and outpatients) were compared in 4 different digoxin assays: (a) ACS™ Digoxin (ACS) developed for the automated chemiluminescent Ciba Corning ACS 180^® system, (b) Baxter Stratus™ (Stratus, a fluoroimmunoassay), (c) Ciba-Corning Magic^TM (Magic, a radioimmunoassay), and (d) an in-house radioimmunoassay (RIA). The ACS^TM and RIA were also compared for their cross-reactivity to four principal digoxin metabolites.

Results and Conclusion: Among the nondigitalized specimens, no significant DLIF interference was found for all 4 assays among the pregnant women or liver and transplant patients. However, the neonates registered high DLIF interference with Magic™ and RIA, but none for ACS™ or Stratus™. DLIF interference in renal samples was highest in the Magic assay and lowest in RIA. Among the specimens with digoxin, a higher number of discrepant samples were found from the sick patients than from outpatients. In 75% of such discrepant samples, the ACS™ result was less than other assay results, suggesting DLIF as the probable cause. The two assays differed most in their cross-reactivity to the deglycated metabolites, digoxigenin and its mono-digitoxoside.     

Effect of high- versus low-dose angiotensin converting enzyme inhibition on cytokine levels in chronic heart failure

OBJECTIVES

We examined the effect of long-term treatment with two doses of the angiotensin converting enzyme (ACE) inhibitor enalapril on various immunological variables in patients with chronic congestive heart failure (CHF).

BACKGROUND

Immunological mediators are increasingly recognized to play a pathogenic role in the pathophysiology of CHF. Whether ACE inhibitor therapy modifies immunological variables has not previously been investigated.

METHODS

Seventy-five patients (mean age 52 ± 11 years) with CHF were randomized between low- (5 mg daily) and high-dose (40 mg daily) enalapril in a double-blind trial. Circulating levels of immunological parameters (i.e., proinflammatory cytokines, chemokines and adhesion molecules) were measured at baseline, at 10 weeks and at the end of the study (34 weeks).

RESULTS

All immunological parameters, except soluble interleukin (IL)-6 receptor, were increased in CHF compared with 21 healthy controls. During the study immunoreactive IL-6 levels decreased (p < 0.05) and soluble IL-6 receptor increased (p < 0.05) during high-dose but not during low-dose enalapril therapy. Furthermore, IL-6 bioactivity decreased only during the high-dose (p < 0.001), resulting in a significant difference in change during treatment between the two dosage groups (p < 0.001). This decrease in IL-6 bioactivity was significantly associated with decreased interventricular septum thickness as assessed by echocardiography (r = 0.56, p = 0.013). No other variables changed during treatment.

CONCLUSIONS

In patients with severe CHF, high-dose enalapril therapy is associated with a significant decrease in IL-6 activity. However, despite treatment with a high-dose ACE inhibitor, a persistent immune activation exists in these patients which may be of importance for the progression of CHF.     

HIV testing in 2006: issues and methods

Infection with HIV and subsequent development of AIDS is a pandemic. The Joint United Nations Program on HIV/AIDS together with the WHO and many relevant funding bodies demand that those infected should be reliably identified so that people who need, or will need, therapy may be provided for over time. This means that there is a renewed interest in testing for HIV and in laboratories’ performances and quality. Whatever the conditions under which testing is performed, and whatever the levels of training, the tests and their outcomes must exhibit equivalent, high standards of performance and reliable results. This is regardless of whether testing is conducted in the most sophisticated laboratories (either diagnostic or transfusion screening) to voluntary testing and counseling centers where those conducting testing may not be technically trained. This is not currently the case, especially in some places where HIV is most prevalent. To achieve uniformly high performance standards, quality assurance programs are imperative, but currently not sufficiently valued to be well supported with adequate funding or human resources. Accurate HIV testing is a cornerstone of blood safety, diagnosis of infection, patient management and surveillance.     

D-dimer and its relationship to fibrinogen/fibrin degradation products (FDPs) in disorders associated with activation of coagulation or fibrinolytic systems

Levels of D-dimer and fibrinogen/fibrin degradation products (FDPs) are significantly elevated in patients with deep venous thrombosis, pulmonary embolism, disseminated intravascular coagulation, or other complications. The diagnosis of these disorders can be difficult, time-consuming, and expensive. Assays for the detection of FDPs and D-dimer are used in many laboratories to investigate these disorders. The aim of this study was to compare plasma D-dimer levels obtained by the immuno-turdimetric method (Liatest D-Dimer Diagnostica Stago, Asnières, France) with plasma FDPs were measured by latex agglutination to investigate the relationship between these parameters. These immunoassays were tested in 144 blood samples from patients with suspected disorders associated with activation of coagulation or fibrinolytic systems. D-dimer and FDPs assays were performed in plasma samples by the use of Liatest D-dimer and plasma FDPs (Diagnostica Stago), respectively. Patients were divided into four groups according to plasma D-dimer levels. In group 1, 47.4% had negative FDPs and 52.6% had positive FDPs. In group 2, 15.4% had negative FDPs and 84.6% had positive FDPs. In group 3, 10.3% had negative FDPs and 89.7% had positive FDPs. All of the patients in group 4 had positive FDPs. It was shown that plasma D-dimer levels measured by Liatest D-dimer have a relation to FDP levels measured by latex agglutination.