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Sera Samples (sera + sample)
Selected AbstractsNeutralizing antibody response variation against dengue 3 strainsJOURNAL OF MEDICAL VIROLOGY, Issue 10 2008Mayling Alvarez Abstract To evaluate the neutralizing antibody activity of a human sera panel against seven strains of the homotypic virus. Sera were collected from DENV-3 immune individuals. Two DENV-3 genotypes and strains isolated at different time-points during the 2000 and 2001,2002 Havana epidemics were included. A panel of 20 late convalescent sera collected 16,18 months after acute illness from DF and DHF patients are studied. These individuals were infected during the 2001,2002 Havana DENV-3 epidemic. All but four sera collected from DF cases had a secondary DENV-1/DENV-3 infection. Sera neutralizing antibody titer against the seven DENV-3 strains were determined by plaque reduction neutralization technique. Sera samples were tested simultaneously. Studied sera showed higher levels of neutralizing antibodies to DENV-3 strains of genotype III compared to genotype V. Interesting, higher levels of neutralizing antibodies were detected to DENV-3 strain isolated at the end of the epidemic 2001,2002. An increased tendency of GMT of neutralizing antibodies according to epidemic evolution was observed for the 2001,2002 outbreak. In general, antibody levels in sera collected from DF cases were higher. Differences in the neutralization capacity of immune DENV-3 sera tested against two homologous genotypes including strains of the same genotype are demonstrated. Observed results suggest that virus changed in the course of the epidemic. The implications of this finding in terms of dengue pathogenesis and vaccine development need to be considered. J. Med. Virol. 80:1783,1789, 2008. © 2008 Wiley-Liss, Inc. [source] Novel TTV variants isolated in an epidemic of hepatitis of unknown etiologyJOURNAL OF MEDICAL VIROLOGY, Issue 1 2002Zhihua Liu Abstract TT virus (TTV) is a recently discovered single-stranded DNA virus that has been reported to be associated with elevated transminase levels in the patients with posttransfusion hepatitis of unknown etiology. TTV prevalence is very high in the common population and its pathogenicity remains unclear. In this study, we performed an epidemiological study to investigate the infection rate of TTV and its role in an epidemic of unknown-etiology hepatitis. Moreover, two TTV isolates named L01 and L02 were cloned from the serum of a patient with unknown-etiology hepatitis. Eighty-one subjects were included in the study and were divided into two groups: 18 in the case group and 63 in the control group. TTVDNA was detected by nested PCR from sera samples. The infection rates of TTV in case and control groups were 33.3 and 38.9%, respectively. There was no significant difference between the two groups. Homology analysis showed that L01 had a very poor homology with other TTV isolates and L02, and L02 was 75.5% identical to JA10. The result does not support TTV as a causative agent in this epidemic. The genetic divergence between L01 and other TTV isolates beyond genotype, so it represents a new genotype of TTV. J. Med. Virol. 67:113,117, 2002. © 2002 Wiley-Liss, Inc. [source] Occult hepatitis B virus infection in patients with autoimmune liver diseasesLIVER INTERNATIONAL, Issue 3 2009Sarah P. Georgiadou Abstract Background: Occult hepatitis B virus (HBV) infection is characterized by undetectable serum HBV surface antigen (HBsAg) but detectable HBV-DNA in serum or liver. Aims: To determine the prevalence and clinical impact of occult HBV in autoimmune liver diseases as similar data are missing. Methods: One hundred and ninety-six sera samples from HBsAg-negative patients, including 66 autoimmune hepatitis (AIH), 93 primary biliary cirrhosis (PBC) and 37 primary sclerosing cholangitis (PSC), were investigated for HBV-DNA using the polymerase chain reaction (PCR) before treatment initiation. One hundred and three serial samples from 38 AIH patients under immunosuppression and 282 selected blood donors (HBsAg negative; antibodies to HBV-core antigen positive) were also investigated. Fourteen available paraffin-embedded AIH liver samples were also investigated for HBV-DNA by nested-PCR. Results: Hepatitis B virus DNA was detected in the serum of 24/196 patients (12.2%) and 0/282 donors (P=0.0000). Nine patients had AIH (13.6%), eight had PBC (8.6%) and seven had PSC (18.9%) (P=0.0000 vs healthy). HBV-DNA detection in AIH livers was higher than in serum. HBV-DNA was associated neither with HBV markers nor with epidemiological, laboratory and clinical data. Serial testing of AIH patients revealed two HBV-DNA-negative patients before treatment becoming positive during treatment, while all HBV-DNA-positive patients before immunosuppression became negative. Conclusion: Based mainly on serum HBV-DNA, we found a significant proportion of autoimmune liver disease patients with occult HBV compared with donors. However, taking into account our results in a small number of liver tissues, it should be emphasized that occult HBV could be even higher when both serum and liver specimens are investigated. Occult HBV does not seem to affect the clinical and laboratory features of the diseases, while AIH patients with occult HBV under immunosuppression do not deteriorate during follow-up. [source] Visceral schistosomiasis of domestic animals in India: humoral immune status of infected cattle, sheep and goats against major polypeptide antigens of Schistosoma indicum and S. spindalePARASITE IMMUNOLOGY, Issue 4 2004A. Singh SUMMARY Polypeptide profiles of Schistosoma indicum and S. spindale adult worm homogenates were obtained by sodium dodecyl sulphate-polyacrylamide gel electrophoresis. Humoral immune status of infected cattle, sheep and goats against Schistosoma indicum and S. spindale Ags was determined by immunoblot analysis and by indirect ELISA using four major polypeptides of approximate molecular masses 45 kDa, 40 kDa, 28 kDa and 15 kDa electro-eluted from the gel slices. Cattle sera samples had higher levels of antibodies against Si/s40 and Si/s28 than against Si/s45 antigen. Reasons have been discussed for the absence of detectable levels of anti-Si/s28, -Si/s45 and -Si/s40 antibodies in a significant number of sera samples from S. indicum egg-positive sheep. [source] ORIGINAL ARTICLE: In situ Reconstruction of Humoral Immune Response Against Sperm: Comparison of SCID and NOD/SCID Mouse ModelsAMERICAN JOURNAL OF REPRODUCTIVE IMMUNOLOGY, Issue 2 2009Beata Grygielska Problem, Comparison of two types of immunocompromised mouse strains (SCID and NOD/SCID) for production of human antisperm antibodies (AsA). Method of study, Human peripheral blood lymphocytes (PBL) were grafted to mouse peritoneal cavity and sensitized with natively glycosylated and N-deglycosylated sperm extracts. Results and conclusion, NOD/SCID mice inoculated with hu-PBLs exhibited higher AsA titres with a tendency for greater sperm agglutination than human AsA raised in SCID mouse model. A comparison between ,native' and deglycosylated sperm extracts revealed higher agglutination titres by sera induced with the latter ones. Inhibitory effect of human polyclonal AsA in sperm penetration assay, however, produced opposite results to that for agglutination. Western immunoblotting was used to evaluate reactive sperm antigens prior to and after in situ sensitization showing multiple bands different from positive reactions brought by original sera of in vivo primed AsA-positive males. It seems that in situ generated AsA recognized sperm entities different from those revealed by blood donor's sera samples. [source] Differential Capture of Serum Proteins for Expression Profiling and Biomarker Discovery in Pre- and Posttreatment Head and Neck Cancer Samples,THE LARYNGOSCOPE, Issue 1 2008Gary L. Freed MD Abstract Introduction: A long-term goal of our group is to develop proteomic-based approaches to the detection and use of protein biomarkers for improvement in diagnosis, prognosis, and tailoring of treatment for head and neck squamous cell cancer (HNSCC). We have previously demonstrated that protein expression profiling of serum can identify multiple protein biomarker events that can serve as molecular fingerprints for the assessment of HNSCC disease state and prognosis. Methods: An automated Bruker Daltonics (Billerica, MA) ClinProt matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) mass spectrometer was used. Magnetic chemical affinity beads were used to differentially capture serum proteins prior to MALDI-TOF analysis. The resulting spectra were analyzed using postprocessing software and a pattern recognition genetic algorithm (ClinProt 2.0). An HNSCC cohort of 48 sera samples from 24 patients consisting of matched pretreatment and 6 to 12 month posttreatment samples was used for further analysis. Low-mass differentially expressed peptides were identified using MALDI-TOF/TOF. Results: In the working mass range of 1,000 to 10,000 m/z, approximately 200 peaks were resolved for ionic bead capture approaches. For spectra generated from weak cation bead capture, a k-nearest neighbor genetic algorithm was able to correctly classify 94% normal from pretreatment HNSCC samples, 80% of pretreatment from posttreatment samples, and 87% of normal from posttreatment samples. These peptides were then analyzed by MALDI-TOF/TOF mass spectometry for sequence identification directly from serum processed with the same magnetic bead chemistry or alternatively after gel electrophoresis separation of the captured proteins. We were able to compare this with similar studies using surface-enhanced laser desorption ionization (SELDI)-TOF to show this method as a valid tool for this process with some improvement in the identification of our groups. Conclusions: This initial study using new high-resolution MALDI-TOF mass spectrometry coupled with bead fractionation is suitable for automated protein profiling and has the capability to simultaneously identify potential biomarker proteins for HNSCC. In addition, we were able to show improvement with the MALDI-TOF in identifying groups with HNSCC when compared with our prior data using SELDI-TOF. Using this MALDI-TOF technology as a discovery platform, we anticipate generating biomarker panels for use in more accurate prediction of prognosis and treatment efficacies for HNSCC. [source] Anti-JC virus antibodies: Implications for PML Risk StratificationANNALS OF NEUROLOGY, Issue 3 2010Leonid Gorelik PhD Objective A study was undertaken to establish an enzyme-linked immunosorbent assay (ELISA) to detect JC virus (JCV)-specific antibodies in multiple sclerosis (MS) patients, and to evaluate its potential utility for identifying patients at higher or lower risk (ie, risk stratification) of developing progressive multifocal leukoencephalopathy (PML). Methods A 2-step assay for detecting and confirming the presence of anti-JCV antibodies in human serum and plasma was developed and demonstrated to be both sensitive and specific. ELISA cutpoints were statistically established using sera from >800 MS patients from natalizumab clinical studies. Subsequently, this assay was used to determine the presence of anti-JCV antibodies in natalizumab-treated PML patients where serum samples were collected 16-180 months prior to the diagnosis of PML. Results In our evaluation of natalizumab-treated MS patients, 53.6% tested positive for anti-JCV antibodies, with a 95% confidence interval of 49.9 to 57.3%. The false-negative rate of the ELISA was calculated to be approximately 2.5%, with an upper 1-sided confidence limit of 4.4%. Notably, we observed anti-JCV antibodies in all 17 available pre-PML sera samples, which was significantly different from the 53.6% seropositivity observed in the overall MS study population (p < 0.0001). Interpretation This 2-step assay provides a means to classify MS patients as having detectable or not detectable levels of anti-JCV antibodies. The finding that all 17 of the pre-PML samples that were available tested seropositive, and none tested seronegative, warrants further research on the clinical utility of the anti-JCV antibody assay as a potential tool for stratifying MS patients for higher or lower risk of developing PML. Ann Neurol 2010 [source] A food safety control low mass-range proteomics platform for the detection of illicit treatments in veal calves by MALDI-TOF-MS serum profilingBIOTECHNOLOGY JOURNAL, Issue 11 2009Lorenza Della Donna Abstract Performance enhancing agents (PEAs) are illegally used in cattle and other meat producing species to increase food conversion and lean meat production. Due to the very short breeding cycle, veal calves represent the meat producing bovine category mostly subjected to illicit treatments. These chemical agents are difficult to detect by conventional analytical approaches due to the employment of synergistic formulations at very low dosage and given the use of uncharacterized novel compounds. Such a scenario has fostered a strong interest in the discovery of functional molecular biomarkers for the detection of growth promoting agents in meat producing species. A multivariate MALDI-TOF-MS proteomics platform has been developed using bovine serum samples. Analytical performances have been thoroughly evaluated in order to enable reproducible profiles from 10 ,L sera samples. We propose univariate and multivariate discrimination models capable to identify calves undergoing illicit treatments. In particular, we found a strong discrimination power associated with a polypeptide fragment from ,2-glycoprotein-I. We provide a fundamental proof of concept in the potential application of MALDI-TOF-MS proteomics profiling in the food safety control. [source] Hepatitis B e antigen positive mother hepatitis B e antigen long persistence in her non-infected babyACTA PAEDIATRICA, Issue 2 2007D Selton Abstract We report the case of a baby born to a hepatitis B virus (HBV) carrier mother. This infant had a hepatitis B e antigen (HBeAg) in the serum until 6 months of age. Serial sera samples were analysed for HBV markers. No breakthrough of HBV infection was detected. The origin of this HBV marker has been questioned. Conclusion: HBeAg can persist at a non-infected baby born to an HBeAg-positive mother up to the age of 6 months. [source] | |||||||||||||