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Titers
Kinds of Titers Selected AbstractsABO Antibody Titer and Risk of Antibody-Mediated Rejection in ABO-Incompatible Renal TransplantationAMERICAN JOURNAL OF TRANSPLANTATION, Issue 5 2010A. A. R. Tobian Therapeutic plasma exchange (TPE) preconditioning with immunosuppressive therapy reduces ABO antibody titers, permitting engraftment of ABO-incompatible (ABO-I) kidney transplants. The posttransplant predictive role of ABO antibody titers for antibody-mediated rejection (AMR) is unknown. This retrospective study evaluated 46 individuals who received TPE to permit ABO-I kidney transplantation. ABO antibody titers were performed using donor-type indicator red cells. Seven individuals (15.2%) experienced clinical or subclinical AMR. There was no significant difference between recipient blood group, number of pretransplant TPE and baseline titer between those with and without AMR. At 1,2 weeks posttransplant the median titer was 64 (range 4 , 512) among individuals with AMR and 16 (range 2 , 256) among individuals without AMR. Total agglutination reactivity score was significantly higher among individuals with AMR (p = 0.046). The risk of AMR was significantly higher among individuals with an elevated posttransplant titer of ,64 (p = 0.006). The sensitivity of an elevated posttransplant titer was 57.1% with a specificity of 79.5%. The positive predictive value was 33.3% and the negative predictive value was 91.2%. Most individuals with AMR have an elevated titer, however, the positive predictive value of a high titer for AMR is poor. [source] Juvenile Hormone Binding Protein Titers During Adult Metamorphosis in Manduca sextaENTOMOLOGICAL RESEARCH, Issue 4 2003Young Jin KANG ABSTRACT ABSTRACT During the pupal and adult stages, the JHBP levels displayed a sex-related difference, with females showing higher levels than males. A sharp increase in JHBP levels was observed at day 2 of the pupal stage. After day 2 the JHBP titer declined precipitously, and then remained unchanged until day 12 in males. JHBP titers in females decreased slightly after day 2 and then remained relatively constant until day 12. In both sexes, the JHBP levels showed a steep increase and peaked around day 15. During the previtellogenic period, the JHBP titers declined dramatically until adult ecdysis. During early adult stage, JHBP titiers in the female remained constant at preecdysis level. This information could broaden our understanding of pest physiology during adult metamorphosis, and could have extensive implications for developing insect growth regulators to control agricultural pests. [source] Prevalence of high antibody titers of pertussis in Turkey: reflection of circulating microorganism and a threat to infantsJOURNAL OF CLINICAL LABORATORY ANALYSIS, Issue 3 2007Berrin Esen Abstract Acute pertussis infection among adults can cause its transmission to the larger population, especially to infants and young children, who can develop severe disease. In order to determine an age-dependent pertussis immune response, anti-pertussis toxin (PT) antibody was detected by the indirect enzyme-linked immunosorbent assay (ELISA) method in serum samples from 2,085 healthy subjects ranging in age from 6 months to ,60 years. Also included in the evaluation were responses to a questionnaire including sociodemographic characteristics, vaccination, and infection history. Titers of 50,99 ELISA units (EU)/mL and of ,100,EU/mL were accepted as indicative for recent exposure or infection. In addition, 30,EU/mL was estimated to be a sufficient titer in women of childbearing age to protect their newborns until administration of their first dose of pertussis vaccine. After the age of 4,5 years, presence of high-titered antibodies that increase with age might be a reflection of circulating infection and indicate the magnitude of the threat to infants. According to the questionnaires, in the groups younger than 15 years old, three to four doses of diphtheria toxoid-whole cell pertussis-tetanus toxoid (DwPT) were administered in 47.2 to 77.4%, 91.2 to 100.0%, and 83.5 to 100.0% of participants in Diyarbakir, Samsun, and Antalya, respectively. In addition, up to half of the expectant mothers we studied lacked a sufficient level of estimated antibody titers. To protect infants from life-threatening pertussis infection, improving vaccination coverage to ensure herd immunity and uniformly establishing coverage throughout the country are essential. Furthermore, revaccination with acellular vaccine for schoolchildren as well as for the households of pregnant women is recommended. J. Clin. Lab. Anal. 21:154,161, 2007. © 2007 Wiley-Liss, Inc. [source] Role of enzyme-treated cells in RBC antibody screening using the gel test: a study of anti-RH1, -RH2, and -RH3 antibodiesJOURNAL OF CLINICAL LABORATORY ANALYSIS, Issue 2 2007Jocelyne Conne Abstract The role of enzyme-treated cells (ETCs) in red blood cell (RBC) antibody screening has been the subject of controversy, and its place in the clinical routine remains to be determined. In this work, plasma samples containing anti-RH1 (anti-D; N = 10), anti-RH2 (anti-C; N = 10), or anti-RH3 (anti-E; N = 10) antibodies were studied. The samples were diluted in nonbuffered or buffered normal saline, as well as in a pool of AB plasma samples. Titers and scores were determined by means of the gel test, using the indirect antiglobulin test (IAT) as well as ETCs, with R0r, r,r, or r,r test cells. Our results showed that compared to the IAT, ETCs allowed a clearer detection of anti-RH2 and anti-RH3, but not of anti-RH1 antibodies. Based on our study, it is not clear whether the ETC phase of the gel test should be maintained for RBC antibody screening. J. Clin. Lab. Anal. 21:61,66, 2007. © 2007 Wiley-Liss, Inc. [source] Analyses of amino acid sequences in hypervariable region-1 of hepatitis C virus (HCV) in sera from chimpanzees infected three times with the same HCV strainJOURNAL OF MEDICAL PRIMATOLOGY, Issue 1 2010M. Sugitani Abstract Background, To investigate whether or not the same strain of hepatitis C virus (HCV) can twice re-infect the same chimpanzee, we analyzed nucleic and amino acid sequences in HCV hypervariable region-1 (HVR1). Two chimpanzees were inoculated, three times each, with the same HCV strain during the 1983,1991. After each inoculation, chimpanzees developed acute hepatitis C, and then recovered. Methods, Using sera, HVR1 cloning and antibody to HVR1 major clone measurement were performed. Results, Clones from the first inoculum were divisible into major and minor types. Clones from the second and third inocula, as well as all post-inoculation sera, were essentially identical to the major type. Titers of antibody to HVR1 major clone were consistently low in pre- and post-inoculation sera. Conclusions, Both chimpanzees were re-infected twice with the same strain of HCV. The sequences from the second and third infections were similar to the major sequences in the first inoculum. [source] Antigenic cross-reactivity among Porphyromonas gingivalis serotypesMOLECULAR ORAL MICROBIOLOGY, Issue 3 2000Q. Fan The goal of our research program is to develop a Porphyromonas gingivalis vaccine. Vaccine development requires identification of antigenic components shared by the many clonal types of P. gingivalis. The purpose of the present study was to evaluate the extent and nature of antigenic cross-reactivity among serotypes of P. gingivalis and to identify shared antigenic components. Strains selected to represent serotypes A,D were 33277, A7A1-28 W50 and 381, respectively. Using intact cells, antibodies were raised in rabbits. Titers were assessed by enzyme-linked immunosorbent assay (ELISA) using intact cells as antigen, Western blots were prepared and biologic activity was measured as opsonization (chemiluminescence expressed as mV) and enhancement of phagocytosis and killing by polymorphonuclear leukocytes. Extensive cross-reactivity that varied greatly among serotypes was observed by ELISA. The Western blots showed an even greater extent of cross-reactivity, with shared protein components at approximately 140, 130, 37, 32 and 28 kDa and a shared variable molecular mass smear considered to be lipopolysaccharide and other carbohydrate. Additional protein components at 110, 85, 35 and 20 kDa appeared to be shared by some but not all serotypes. In the functional assays, strains 33277 and 381 were equally well opsonized by anti-33277 and anti-381 (500,650 mV) but opsonized to a much lesser extent by anti-A7A1-28 and anti-W50 (roughly 125 mV and 350 mV respectively). A7A1-28 and W50 were opsonized by all four immune sera almost equally but to a much lower extent (roughly 400 mV and 250 mV respectively). Enhancement of phagocytosis and killing in the presence of active complement mirrored opsonization with the exception that 381 was reasonably well opsonized by anti-A7A1-28 (400 mV) and anti-W50 (350 mV), but poorly killed. The protein components at 140, 130, 37 and 28 kDa shared by all of the four serotypes appear to have potential as vaccine candidate antigens. [source] Generation of stable retrovirus packaging cell lines after transduction with herpes simplex virus hybrid amplicon vectors,THE JOURNAL OF GENE MEDICINE, Issue 3 2002Miguel Sena-Esteves Abstract Background A number of properties have relegated the use of Moloney murine leukemia virus (Mo-MLV)-based retrovirus vectors primarily to ex vivo protocols. Direct implantation of retrovirus producer cells can bypass some of the limitations, and in situ vector production may result in a large number of gene transfer events. However, the fibroblast nature of most retrovirus packaging cells does not provide for an effective distribution of vector producing foci in vivo, especially in the brain. Effective development of new retrovirus producer cells with enhanced biologic properties may require the testing of a large number of different cell types, and a quick and efficient method to generate them is needed. Methods Moloney murine leukemia virus (Mo-MLV) gag-pol and env genes and retrovirus vector sequences carrying lacZ were cloned into different minimal HSV/AAV hybrid amplicons. Helper virus-free amplicon vectors were used to co-infect glioma cells in culture. Titers and stability of retrovirus vector production were assessed. Results Simultaneous infection of two glioma lines, Gli-36 (human) and J3T (dog), with both types of amplicon vectors, generated stable packaging populations that produced retrovirus titers of 0.5,1.2×105 and 3.1,7.1×103 tu/ml, respectively. Alternatively, when cells were first infected with retrovirus vectors followed by infection with HyRMOVAmpho amplicon vector, stable retrovirus packaging populations were obtained from Gli-36 and J3T cells producing retrovirus titers comparable to those obtained with a traditional retrovirus packaging cell line, ,CRIPlacZ. Conclusions This amplicon vector system should facilitate generation of new types of retrovirus producer cells. Conversion of cells with migratory or tumor/tissue homing properties could result in expansion of the spatial distribution or targeting capacity, respectively, of gene delivery by retrovirus vectors in vivo. Copyright © 2002 John Wiley & Sons, Ltd. [source] Relationships between Chlamydia trachomatis Antibody Titers and Tubal Pathology Assessed using Transvaginal Hydrolaparoscopy in Infertile WomenAMERICAN JOURNAL OF REPRODUCTIVE IMMUNOLOGY, Issue 1 2003Hiroaki Shibahara Problem: Since transvaginal hydrolaparoscopy (THL) was introduced as the first-line procedure in the early stages of the exploration of the adnexal structures in infertile women, it has been shown that THL is a less traumatic and a more suitable outpatient procedure than diagnostic laparoscopy. This study was performed to investigate the relationships between Chlamydia trachomatis antibody titers and tubal pathology assessed using THL in infertile women. Methods: The C. trachomatis antibody titers (IgG and IgA) were evaluated by ELISA. The posterior of the uterus and the tubo-ovarian structures were carefully observed, and tubal passage using indigocarmine was confirmed using THL. THL was carried out in 32 infertile women having C. trachomatis antibody in their sera between May 1999 and October 2001. Unilateral salpingectomy had been performed on two of the 32 patients. Results: Tubal occlusion was confirmed in 20 (32.3%) of the 62 tubes, while peritubal adhesion was diagnosed in 37 (59.7%) of the 62 tubes. Using receiver operating characteristics curves, the cut-off value of C. trachomatis IgG antibody titer to predict tubal occlusion was determined to be 3.55. Tubal occlusion was observed in 16 (51.6%) of the 31 tubes in patients with the C. trachomatis IgG antibody titer of more than 3.55, which was significantly higher in four (12.9%) of the 31 tubes having the antibody titer less than 3.55 (P = 0.004). However, there was no correlation between C. trachomatis IgG antibody titer and peritubal adhesion. As for C. trachomatis IgA antibody titer, there was no correlation between antibody titer and tubal occlusion or peritubal adhesion. Conclusions: These results suggest that C. trachomatis infection is significantly associated with tubal pathology. Although the cut-off value of C. trachomatis IgG antibody titer to predict the existence of tubal occlusion was shown to be 3.55, we would suggest that THL or standard laparoscopy is performed to consider appropriate treatments in patients with past C. trachomatis infection because of the high prevalence of peritubal adhesion. [source] Rituximab is effective in the treatment of refractory ophthalmic Wegener's granulomatosisARTHRITIS & RHEUMATISM, Issue 5 2009Simon R. J. Taylor Objective To investigate the efficacy of rituximab in patients with refractory ophthalmic Wegener's granulomatosis (WG). Methods Data from 10 consecutive patients with refractory ophthalmic WG treated with rituximab were retrospectively reviewed. In all patients, the ophthalmic disease was driving treatment decisions, and disease activity had persisted despite standard immunosuppressive treatment. Patients had refractory scleritis (n = 3), orbital granulomas causing optic nerve compromise (n = 4), or a combination of both conditions (n = 3). All patients had been treated with at least 3 different immunosuppressive agents, and 5 patients had previously been treated with tumor necrosis factor , blockade. Rituximab was administered intravenously in 2 doses, 2 weeks apart, in combination with standard treatment. Disease activity was monitored clinically by an interdisciplinary approach, including disease activity scoring, immunodiagnostics, and magnetic resonance imaging, as well as by corresponding reductions in the required dose of conventional medication. Results A beneficial response to treatment with rituximab was seen in all 10 patients, including induction of clinical remission. In all patients, the peripheral blood B cell count fell to zero during treatment with rituximab. Titers of classic antineutrophil cytoplasmic antibodies fell in association with B cell counts, and this reduction was correlated with improved clinical findings. Conclusion In contrast to previous observations, this study showed that treatment with rituximab was associated with clinical improvement in patients with refractory ophthalmic WG. [source] Serological Immunoglobulin G Antibody Titers to Helicobacter pylori in Japanese Brazilian and Non-Japanese Brazilian Gastric Cancer Patients and Controls in São PaulCANCER SCIENCE, Issue 8 2001Naoko Fujioka First page of article [source] Life history of the bird cherry-oat aphid, Rhopalosiphum padi, on transgenic and non-transformed wheat challenged with Wheat streak mosaic virusENTOMOLOGIA EXPERIMENTALIS ET APPLICATA, Issue 1 2009Edgardo S. Jiménez-Martínez Abstract The life history of the bird cherry-oat aphid, Rhopalosiphum padi (L.) (Hemiptera: Aphididae), was studied via laboratory assays on Wheat streak mosaic virus (WSMV)-infected and non-infected transgenic and non-transformed wheat [Triticum aestivum L. (Poaceae)]. Although R. padi is not a WSMV vector, it is known to colonize WSMV-infected wheat plants. Two transgenic soft white winter wheat genotypes, 366-D03 and 366-D8, that express the WSMV coat protein gene, and the WSMV-susceptible non-transformed cultivar Daws were tested. All genotypes showed disease symptoms when infected with WSMV. Whereas plant height was significantly reduced on virus-infected compared to non-infected plants of all genotypes, virus-infected transgenic plants exhibited lower virus titer and lower disease rating scores than Daws. No significant effects of WSMV infection or genotypes were observed on the length of R. padi nymphal development period, nor on their pre-, and post-reproductive periods. Rhopalosiphum padi reproductive period was significantly longer on Daws infected with WSMV than on non-infected plants of this cultivar. In contrast, there were no significant differences in length of R. padi reproductive period between virus-infected and non-infected transgenic plants within a genotype. Rhopalosiphum padi daily fecundity was significantly lower and adult longevity significantly longer on virus-infected than on non-infected plants of all genotypes. Total aphid fecundity and intrinsic rate of increase were not significantly different among treatments. The percentage of winged aphids that developed was greater on WSMV-infected compared to non-infected plants within a genotype. Results indicate that both virus infection status of plants and wheat genotype influence the life history of R. padi. [source] Juvenile Hormone Binding Protein Titers During Adult Metamorphosis in Manduca sextaENTOMOLOGICAL RESEARCH, Issue 4 2003Young Jin KANG ABSTRACT ABSTRACT During the pupal and adult stages, the JHBP levels displayed a sex-related difference, with females showing higher levels than males. A sharp increase in JHBP levels was observed at day 2 of the pupal stage. After day 2 the JHBP titer declined precipitously, and then remained unchanged until day 12 in males. JHBP titers in females decreased slightly after day 2 and then remained relatively constant until day 12. In both sexes, the JHBP levels showed a steep increase and peaked around day 15. During the previtellogenic period, the JHBP titers declined dramatically until adult ecdysis. During early adult stage, JHBP titiers in the female remained constant at preecdysis level. This information could broaden our understanding of pest physiology during adult metamorphosis, and could have extensive implications for developing insect growth regulators to control agricultural pests. [source] Long-term maternal imprinting of the specific B cell repertoire by maternal antibodiesEUROPEAN JOURNAL OF IMMUNOLOGY, Issue 1 2008Katja Fink Abstract Maternal antibodies protect newborns whilst they are immunologically immature. This study shows that maternal antibodies can also shape the B cell repertoire of the offspring long after the maternal antibodies themselves become undetectable. VHDJH gene-targeted (VI10) mice expressing a heavy chain specific for vesicular stomatitis virus (VSV) produce a 20-fold increased spontaneous titer of VSV-neutralizing antibodies. When transferred from mother to offspring, these antibodies prevented accumulation of Ag-specific transitional type,2 and marginal zone B cells with an activated phenotype and favored selection to the B cell follicles. This effect was B cell-intrinsic and lasted up to adulthood. The pups nursed by mothers producing specific antibodies developed higher endogenous antibody titers of this specificity which perpetuated the effects of specific B cell selection into the mature follicular compartment, presumably by blocking auto-Ag-dependent development of transitional type,2 B cells in the spleen. This repertoire change was functional, as following infection of adult mice with VSV, those pups that had received specific maternal antibodies as neonates had increased pre-immune titers and mounted strong early IgG neutralizing antibodies. [source] Enhancement of protective humoral immune responses against Herpes simplex virus-2 in DNA-immunized guinea-pigs using protein boostingFEMS IMMUNOLOGY & MEDICAL MICROBIOLOGY, Issue 1 2008Fatemeh Fotouhi Abstract Genital Herpes is a common sexually transmitted disease that is caused mostly by Herpes simplex virus type 2 (HSV-2). Its prevalence has increased in developing countries in spite of the availability of valuable antiviral drug therapy. Considering the importance of HSV-2 infections, effective vaccines remain the most likely hope for controlling the spread of HSV diseases. In the present study, the complete HSV-2 glycoprotein D gene was isolated and cloned into different plasmid vectors to construct a DNA vaccine and prepare recombinant subunit vaccines using a baculovirus expression system. The vaccines were tested alone or in combination to evaluate their ability to induce protective immunity in guinea-pigs against genital HSV infections. Immunization elicited humoral responses as measured by neutralization tests and enzyme-linked immunosorbent assay, and immunized animals had less severe genital skin disease as well as reduced replication of the challenging virus in the genital tract during experimental infection. Our results further demonstrate that DNA priming-protein boosting induced a neutralizing antibody titer higher than that obtained with DNA,DNA vaccination. The massive increase of antibody titer following DNA priming-protein boosting might be attributed to a recall of B cell memory. [source] Role of anti-,-glucan antibody in host defense against fungiFEMS IMMUNOLOGY & MEDICAL MICROBIOLOGY, Issue 1 2005Ken-ichi Ishibashi Abstract We have recently detected an anti-,-glucan antibody in normal human and normal mouse sera. The anti-,-glucan antibody showed reactivity to pathogenic fungal Aspergillus and Candida cell wall glucan. Anti-,-glucan antibody could bind whole Candida cells. It also enhanced the candidacidal activity of macrophages in vitro. The anti-,-glucan antibody titer of DBA/2 mice intravenously administered either Candida or Aspergillus solubilized cell wall ,-glucan decreased remarkably dependent on dose. Moreover, in deep mycosis patients, the anti-,-glucan antibody titer decreased, and this change correlated with clinical symptoms and other parameters such as C-reactive protein. It was suggested that the anti-,-glucan antibody formed an antigen,antibody complex and participated in the immune response as a molecule recognizing pathogenic fungi. [source] Genetic improvement of processes yielding microbial productsFEMS MICROBIOLOGY REVIEWS, Issue 2 2006Jose L. Adrio Abstract Although microorganisms are extremely good in presenting us with an amazing array of valuable products, they usually produce them only in amounts that they need for their own benefit; thus, they tend not to overproduce their metabolites. In strain improvement programs, a strain producing a high titer is usually the desired goal. Genetics has had a long history of contributing to the production of microbial products. The tremendous increases in fermentation productivity and the resulting decreases in costs have come about mainly by mutagenesis and screening/selection for higher producing microbial strains and the application of recombinant DNA technology. [source] Low-dose immune tolerance induction for paediatric haemophilia patients with factor VIII inhibitorsHAEMOPHILIA, Issue 2 2008A. UNUVAR Summary., The development of an inhibitor against factor VIII (FVIII) is a serious complication in children with haemophilia A. Immune tolerance induction (ITI) therapy is generally considered to be the best approach to eradicate the inhibitor. In this paper, the low-dose (,50 IU kg,1 twice or three times weekly with plasma-derived factor concentrates) ITI regimen used in Turkey is discussed. This regimen was given to 21 haemophilia A patients with high titer inhibitors. The median age at the beginning of ITI was 9 years and exposure days were 25. The median pre-ITI historical peak inhibitor titer, and inhibitor titer when ITI started were 80 BU (range 6.0,517), 19.2 BU (range 3.6,515), respectively. Complete immune tolerance was defined as the time at which at least two negative inhibitor assays was obtained with no anamnestic response. Our two cases were not reached in follow-up period. Immune tolerance could be achieved in 5 of 19 (26.3%) patients within a median time of 6 months. Partial tolerance was obtained in 7 patients while treatment failed in spite of significant decreased inhibitor levels in the other patients. A relapse developed in one immune-tolerized patient, one year later. The level of inhibitor titer at the beginning of ITI (,10 BU), the pre-ITI historical peak inhibitor titer (<50 BU), and the time between the first diagnosis inhibitor to starting ITI (<12 months) were main factors in the success (complete or partial tolerance) of ITI. In conclusion, the outcome of low-dose ITI protocol was not satisfactory in this retrospective study. [source] Serum hepatitis B surface antigen and hepatitis B e antigen titers: Disease phase influences correlation with viral load and intrahepatic hepatitis B virus markers,,HEPATOLOGY, Issue 6 2010Alexander J.V. Thompson Although threshold levels for hepatitis B surface antigen (HBsAg) and hepatitis B e antigen (HBeAg) titers have recently been proposed to guide therapy for chronic hepatitis B (CHB), their relationship to circulating hepatitis B virus (HBV) DNA and intrahepatic HBV replicative intermediates, and the significance of emerging viral variants, remains unclear. We therefore tested the hypothesis that HBsAg and HBeAg titers may vary independently of viral replication in vivo. In all, 149 treatment-naïve CHB patients were recruited (HBeAg-positive, n = 71; HBeAg-negative, n = 78). Quantification of HBeAg and HBsAg was performed by enzyme immunoassay. Virological characterization included serum HBV DNA load, HBV genotype, basal core promoter (BCP)/precore (PC) sequence, and, in a subset (n = 44), measurement of intrahepatic covalently closed circular DNA (cccDNA) and total HBV DNA, as well as quantitative immunohistochemical (IHC) staining for HBsAg. In HBeAg-positive CHB, HBsAg was positively correlated with serum HBV DNA and intrahepatic cccDNA and total HBV DNA (r = 0.69, 0.71, 0.76, P < 0.01). HBeAg correlated with serum HBV DNA (r = 0.60, P < 0.0001), although emerging BCP/PC variants reduced HBeAg titer independent of viral replication. In HBeAg-negative CHB, HBsAg correlated poorly with serum HBV DNA (r = 0.28, P = 0.01) and did not correlate with intrahepatic cccDNA nor total HBV DNA. Quantitative IHC for hepatocyte HBsAg confirmed a relationship with viral replication only in HBeAg-positive patients. Conclusion: The correlation between quantitative HBsAg titer and serum and intrahepatic markers of HBV replication differs between patients with HBeAg-positive and HBeAg-negative CHB. HBeAg titers may fall independent of viral replication as HBeAg-defective variants emerge prior to HBeAg seroconversion. These findings provide new insights into viral pathogenesis and have practical implications for the use of quantitative serology as a clinical biomarker. (HEPATOLOGY 2010) [source] HCV796: A selective nonstructural protein 5B polymerase inhibitor with potent anti-hepatitis C virus activity In Vitro, in mice with chimeric human livers, and in humans infected with hepatitis C virus,HEPATOLOGY, Issue 3 2009Norman M. Kneteman Anti-hepatitis C virus (HCV) drug development has been challenged by a lack of experience with inhibitors inclusive of in vitro, animal model, and clinical study. This manuscript outlines activity and correlation across such a spectrum of models and into clinical trials with a novel selective nonstructural protein 5B (NS5B) polymerase inhibitor, HCV796. Enzyme assays yielded median inhibitory concentration (IC50) values of 0.01 to 0.14 ,M for genotype 1, with half maximal effective concentration (EC50s) of 5 nM and 9 nM against genotype 1a and 1b replicons. In the chimeric mouse model, a 2.02 ± 0.55 log reduction in HCV titer was seen with monotherapy, whereas a suboptimal dose of 30 mg/kg three times per day in combination with interferon demonstrated a 2.44 log reduction (P = 0.001 versus interferon alone) Clinical outcomes in combination with pegylated interferon and ribavirin have revealed additive efficacy in treatment naïve patients. Abnormal liver function test results were observed in 8% of HCV-796 patients treated for over 8 weeks, resulting in suspension of further trial activity. Conclusion: The RNA-dependent RNA polymerase inhibitor HCV796 demonstrated potent anti-HCV activity consistently through enzyme inhibition assays, subgenomic replicon, and chimeric mouse studies. Strong correlations of outcomes in the mouse model were seen with subsequent clinical trials, including a plateau in dose-related antiviral activity and additive impact from combination therapy with interferon. These outcomes demonstrate the utility of the range of in vitro and in vivo models now available for anti-HCV drug development and support the potential utility of polymerase inhibitors in future combination therapies for HCV treatment. (HEPATOLOGY 2009.) [source] Waning immunity to plasma-derived hepatitis B vaccine and the need for boosters 15 years after neonatal vaccinationHEPATOLOGY, Issue 6 2004Chun-Yi Lu Neonatal immunization with hepatitis B (HB) vaccine is highly effective; however, more needs to be learned about the duration of protection and indications for boosters. We measured antibody to HB core antigen (anti-HBc), HB surface antigen (HBsAg), and pre- and postbooster titers of HBsAg antibody (anti-HBs) 15 years after primary neonatal immunization with plasma-derived HB vaccines in 2 cohorts of 15-year-old children. Group A consisted of 78 children who were born to HB e antigen,positive HBsAg carrier mothers and had developed protective levels of anti-HBs antibodies (,10 mIU/mL) following HB immunization. Group B consisted of 113 apparently healthy children whose anti-HBs titers after vaccination were unknown. Anti-HBs was undetectable (antibody titer <10 mIU/mL) in 29.9% in group A and 62.4% in group B (P < .001). Anti-HBc was detected in 33.3 % in group A and 4.4 % in group B (P < .001). After a single booster dose of HB vaccine, 2.7% in group A and 3.3% in group B remained anti-HBs,negative. A blunted serological response was noted in approximately 20% in both groups. One HBsAg carrier was detected in group A (1.3%) and 4 in group B (3.5%). Fifteen years after neonatal immunization with plasma-derived HB vaccine, a large proportion of children exhibited waning immunity. This poses the risk of breakthrough infection. A single booster augmented the serological response to the vaccine in most but not all subjects. In conclusion, our findings suggest that one or more booster immunizations are needed in seronegative subjects by at least 15 years following neonatal immunization with plasma-derived HB vaccine. (HEPATOLOGY 2004;40:1415,1420.) [source] Suppression of HCV-specific T cells without differential hierarchy demonstrated ex vivo in persistent HCV infectionHEPATOLOGY, Issue 6 2003Kazushi Sugimoto Hepatitis C virus (HCV) has a high propensity for persistence. To better define the immunologic determinants of HCV clearance and persistence, we examined the circulating HCV-specific T-cell frequency, repertoire, and cytokine phenotype ex vivo in 24 HCV seropositive subjects (12 chronic, 12 recovered), using 361 overlapping peptides in 36 antigenic pools that span the entire HCV core, NS3-NS5. Consistent with T-cell-mediated control of HCV, the overall HCV-specific type-1 T-cell response was significantly greater in average frequency (0.24% vs. 0.04% circulating lymphocytes, P = .001) and scope (14/36 vs. 4/36 pools, P = .002) among the recovered than the chronic subjects, and the T-cell response correlated inversely with HCV titer among the chronic subjects (R = ,0.51, P = .049). Although highly antigenic regions were identified throughout the HCV genome, there was no apparent difference in the overall HCV-specific T-cell repertoire or type-1/type-2 cytokine profile relative to outcome. Notably, HCV persistence was associated with a reversible CD4-mediated suppression of HCV-specific CD8 T cells and with higher frequency of CD4+CD25+ regulatory T cells (7.3% chronic vs. 2.5% recovered, P = .002) that could directly suppress HCV-specific type-1 CD8 T cells ex vivo. In conclusion, we found that HCV persistence is associated with a global quantitative and functional suppression of HCV-specific T cells but not differential antigenic hierarchy or cytokine phenotype relative to HCV clearance. The high frequency of CD4+CD25+ regulatory T cells and their suppression of HCV-specific CD8 T cells ex vivo suggests a novel role for regulatory T cells in HCV persistence. [source] Immunization with an adjuvant hepatitis B vaccine after liver transplantation for hepatitis B-related diseaseHEPATOLOGY, Issue 4 2003Ulrich Bienzle M.D. Patients who undergo transplantation for hepatitis B virus (HBV)-related diseases are treated indefinitely with hepatitis B hyperimmunoglobulin (HBIG) to prevent endogenous HBV reinfection of the graft. Active immunization with standard hepatitis B vaccines in these patients has recently been reported with conflicting results. Two groups of 10 liver transplant recipients on continuous HBIG substitution who were hepatitis B surface antigen (HBsAg) positive and HBV DNA negative before transplantation were immunized in a phase I study with different concentrations of hepatitis B s antigen formulated with the new adjuvants 3-deacylated monophosphoryl lipid A (MPL) and Quillaja saponaria (QS21) (group I/vaccine A: 20 ,g HBsAg, 50 ,g MPL, 50 ,g QS21; group II/vaccine B: 100 ,g HBsAg, 100 ,g MPL, 100 ,g QS21). Participants remained on HBIG prophylaxis and were vaccinated at weeks 0, 2, 4, 16, and 18. They received 3 additional doses of vaccine B at bimonthly intervals if they did not reach an antibody titer against hepatitis B surface antigen (anti-HBs) greater than 500 IU/L. Sixteen (8 in each group) of 20 patients (80%) responded (group I: median, 7,293 IU/L; range, 721,45,811 IU/L anti-HBs; group II: median, 44,549 IU/L; range, 900,83, 121 IU/L anti-HBs) and discontinued HBIG. They were followed up for a median of 13.5 months (range, 6,22 months). The vaccine was well tolerated. In conclusion, most patients immunized with the new vaccine can stop HBIG immunoprophylaxis for a substantial, yet to be determined period of time. (Hepatology 2003;38:811,819). [source] Development of antibody to hepatitis B surface antigen after liver transplantation for chronic hepatitis BHEPATOLOGY, Issue 1 2003Chung-Mau Lo Patients with chronic hepatitis B virus (HBV) infection have a defective HBV-specific immune response, and the spontaneous development of antibody against hepatitis B surface antigen (anti-HBs) after liver transplantation has not been observed. We report the spontaneous production of anti-HBs in 21 of 50 (42%) patients receiving lamivudine monoprophylaxis after liver transplantation. Seroconversion to anti-HBs status (>10 mIU/mL) was found at a median of 8 days (range, 1 to 43 days) after transplantation. In each case, serial serum samples showed a >100% increase in antibody titer as compared with that of day 7 after transplantation in the absence of any blood product transfusion. The anti-HBs titer increased to a maximum within 3 months, and the peak titer was <100 mIU/mL in 10 patients, 100 to 1000 mIU/mL in 5 patients, and >1,000 mIU/mL in 6 patients. In 12 patients, anti-HBs disappeared from serum at a median of 201 days (range, 24 to 414 days), whereas the other 9 patients remained positive for anti-HBs at a median of 221 days (range, 94 to 1,025 days) after transplantation. Patients in whom anti-HBs in serum developed had a more rapid clearance of serum hepatitis B surface antigen (HBsAg) (log rank test, P = .011). Using logistic regression analysis, the only predictor of anti-HBs production was an HBV-immune donor (odds ratio, 18.9; 95% confidence interval, 3.2 to 112.4; P = .001). In conclusion, patients who undergo liver transplantation for chronic hepatitis B using lamivudine prophylaxis may develop anti-HBs spontaneously. The antibody is likely to be of donor origin, suggesting the possibility of adoptive immunity transfer through a liver graft. [source] Two week induction of interferon-beta followed by pegylated interferon alpha-2b and ribavirin for chronic infection with hepatitis CHEPATOLOGY RESEARCH, Issue 8 2010Keiji Matsui Objectives:, To elucidate the efficacy of interferon (IFN)-beta induction therapy followed by pegylated IFN alpha and ribavirin for chronic infection with hepatitis C virus (HCV). Methods:, Patients chronically infected with HCV genotype 1, high titer were enrolled. Twice daily bolus injections of 3 million units IFN-beta were administered for 14 days. Thereafter, weekly injection of pegylated IFN alpha 2b and daily intake of ribavirin were followed. Therapy duration was adjusted according to the response to the therapy. When time to an undetectable HCV-RNA was 1, 2, 4, 8, and 12 weeks, total duration of therapy was 12, 24, 36, 48 and 60 weeks, respectively. Patients who failed to achieve an undetectable HCV-RNA within 12 weeks discontinued therapy on 12 week. Results:, Among the 101 patients treated, 56 (55.4%) achieved sustained virological response (SVR). SVR rate for each treatment duration was 10/10 for 12 weeks, 12/14 for 24 weeks, 18/19 for 36 weeks, 15/26 for 48 weeks, 1/4 for 60 weeks and 0/28 for patients who discontinued therapy at 12 weeks. Mean time to an undetectable HCV-RNA was 35.5 ± 2.7 days. Mean therapy duration was 27.3 ± 1.4 weeks. Using a cut off value of 21.5 fmol/L of HCV core-antigen in the first week, SVR could be predicted by sensitivity of 0.91 and specificity of 0.78. Conclusion:, IFN-beta induction therapy resulted in acceptable SVR rates despite short therapy duration. Steep reduction of HCV by IFN-beta enables us to predict SVR in the first week of therapy. [source] Double-dose double-phase use of second generation hepatitis B virus vaccine in patients after living donor liver transplantation: Not an effective measure in transplant recipientsHEPATOLOGY RESEARCH, Issue 1 2009Noriyo Yamashiki Aims:, Post-transplant active immunization for chronic hepatitis B patients has been attempted in several studies with controversial results. We assessed the effect of a double-dose double-phase vaccination regimen among partial living donor liver recipients. Methods:, Eighteen patients who underwent liver transplantation (LT) for chronic hepatitis B and two non-hepatitis B virus (HBV)-infected patients who received hepatitis B core antibody (HBcAb)-positive donor organs were recruited 18,78 months after LT. All were on hepatitis B immunoglobulin (HBIG) mono-prophylaxis before and throughout vaccination, to maintain hepatitis B surface antibody (HBsAb) titers of more than 100 IU/mL. Recombinant hepatitis B surface antigen vaccine (40 µg) was administered intramuscularly during weeks 0, 4, 8, 24, 28 and 32. Results:, The patients consisted of 15 males and five females with a median age of 52 (39,59) years. None developed a sufficient HBsAb titer above 500 IU/mL by week 48. In two patients whose maximum HBsAb titer increased to above 300 IU/mL, we attempted to skip HBIG, but shortly thereafter the titer dropped below 100 IU/mL and HBIG administration was resumed. Although the HBIG dose was reduced during and after vaccination, cessation of administration was not achieved. Conclusion:, Double-dose double-phase use of second generation recombinant vaccine was not effective in this study population. The selected population should be targeted for a conventional vaccine regimen, and different approaches, such as strong adjuvant or pre-S containing protein, should be further tested in a larger number of patients after LT for chronic hepatitis B. [source] Long-term clinical outcome of living-donor liver transplantation for primary biliary cirrhosisHEPATOLOGY RESEARCH, Issue 2007Etsuko Hashimoto Aim:, We described the recurrence of primary biliary cirrhosis (PBC) after living donor liver transplantation (LDLT) (Liver Transplantation, 7, 2001: 588). However, since the follow-up period in that study was insufficiently long (median 35.5 months), we performed a long-term study to further characterize recurrence of PBC after LDLT. Patients:, From 1991 to 2006, 15 patients with end-stage PBC underwent LDLT at Tokyo Women's Medical University. Of these patients, we studied 8 PBC patients (age 29 to 51 years, all females) who survived LDLT for more than 5 years. The follow-up period for these patients ranged form 68 to 120 months. Immunosuppression was maintained with tacrolimus and prednisone. Laboratory examinations performed in every patient and donor before LDLT included routine biochemical studies, antimitochondrial antibody (AMA) by immunofluorescence (IF), anti-M2 by enzyme-linked immunosorbent assay as well as antinuclear antibody (ANA) by IF, and immunoglobulin. After LDLT, the same laboratory examinations were performed in patients every 6 months. Liver biopsy was performed when patients exhibited clinical or biochemical signs of graft dysfunction. In addition, protocol biopsy was performed every 1 to 2 years after LDLT. Results:, At the time of LDLT, all patients had end-stage cholestatic liver failure. Seven patients were positive for AMAand anti-M2 while 1 patient was negative for these markers but strongly positive for ANA. Donors were blood relatives in 6 cases, and 2 donors who were not blood relatives still exhibited multiple HLA matches with the recipients. At the end of the study in May 2006, all patients were doing well. On laboratory examination, mild abnormal liver function test results were found in 4 patients: 3 were probably due to recurrence of PBC, 1 resulted from nonalcoholic steatohepatitis. Comparison of the AMA titer between before LDLT and the most recent follow-up visit showed an increase in three patients, a decrease in two patients and no change in three patients. In contrast, the ANA titer increased in five patients. Histologically, strong evidence of recurrent PBC was found in 4 patients, and findings compatible with PBC were present in 2 additional patients. Conclusions:, Although the number of our patients is small, our findings confirm that PBC can recur at high frequency after LDLT. However, this complication has not developed to advanced stages and has not caused appreciable symptoms in our patients, all of whom have a good quality of life. [source] Specific antibodies against recombinant protein of insertion element 900 of Mycobacterium avium subspecies paratuberculosis in Japanese patients with Crohn's diseaseINFLAMMATORY BOWEL DISEASES, Issue 1 2006Hiroshi Nakase Background:Mycobacterial avium subspecies paratuberculosis (MAP) infection has been hypothesized as an etiological factor of Crohn's disease (CD). However, the involvement of MAP in the pathophysiology of CD is controversial. The aim of this study is to investigate whether MAP is involved in the pathogenesis of CD with the glutathione S-transferase fusion recombinant protein encoding a portion of insertion element (IS) 900 (IS900-GST), which is specific for MAP. Methods: Serum samples from the patients with CD (n = 50), ulcerative colitis (n = 40), colonic tuberculosis (n = 20), and non-IBD controls (n = 44), were applied for solid-phase enzyme-linked immunosorbent assay (ELISA) to detect antibodies against MAP and Saccharomyces cerevisiae. IS900-GST, which was made by the pGST-4T-2 vector inserted with polymerase chain reaction-amplified IS900DNA, was used as an antigen of MAP. Moreover, we studied the relationship between antibodies against IS900-GST and clinical characteristics. Results: ELISA showed that the serum level of immunoglobulin G and immunoglobulin A antibodies against IS900-GST (anti-IS900) in patients with CD were significantly higher than those with ulcerative colitis, colonic tuberculosis, and control subjects. The levels of anti-IS900 tended to be higher in CD patients with small intestinal involvement than with colonic involvement alone. Anti-IS900 in patients with penetrating- and stricture-type CD was significantly higher than with inflammatory-type CD. Furthermore, a negative correlation was found between the titer of anti-IS900 and disease duration. Anti-IS900 was not associated with surgical treatment nor was it associated with the use of immunosuppressants. No significant correlation was observed between the serum levels of anti-IS900 and anti- S cerevisiae antibody. Conclusions: This is the first demonstration of the ELISA system of detecting antibodies against IS900 in IBD patients. MAP could be involved in the pathophysiology of Japanese patients with CD. [source] Influenza virus assays based on virus-inducible reporter cell linesINFLUENZA AND OTHER RESPIRATORY VIRUSES, Issue 5 2009Yunsheng Li Background, Virus-inducible reporter genes have been used as the basis of virus detection and quantitation assays for a number of viruses. A strategy for influenza A virus-induction of a reporter gene was recently described. In this report, we describe the extension of this strategy to influenza B virus, the generation of stable cell lines with influenza A and B virus-inducible reporter genes, and the use of these cells in various clinically relevant viral assays. Each of the cell lines described herein constitutively express an RNA transcript that contains a reporter gene coding region flanked by viral 5,- and 3,-untranslated regions (UTR) and therefore mimics an influenza virus genomic segment. Upon infection of the cells with influenza virus the virus-inducible reporter gene segment (VIRGS) is replicated and transcribed by the viral polymerase complex resulting in reporter gene expression. Findings, Reporter gene induction occurs after infection with a number of laboratory strains and clinical isolates of influenza virus including several H5N1 strains. The induction is dose-dependent and highly specific for influenza A or influenza B viruses. Conclusions, These cell lines provide the basis of simple, rapid, and objective assays that involve virus quantitation such as determination of viral titer, assessment of antiviral susceptibility, and determination of antibody neutralization titer. These cell lines could be very useful for influenza virus researchers and vaccine manufacturers. [source] HORMONAL CONTROL OF THE VITELLOGENESIS IN THE JAPANESE OAK SILKWORM, ANTHERAEA YAMAMAZ (LEPIDOPTERA: SATURNIIDAE)INSECT SCIENCE, Issue 1 2002YE Gong-yin Abstract Effects of ecdysteroid and juvenile hormone (JH) on vitellogenesis of the Japanese oak silkworm, Antheraea yamami are reported in this article. After topical treatment with 20-hydroxyecdysone alone or JH analog (i.e. methoprene) alone and combined treatment with these two chemicals, vitellogenin (Vg) titers in the fat body and haemolymph at the pupal stage were mostly higher than those of the control, indicating that both ecdysteroid and JH exerted a promoting effect on the synthesis of Vg. In contrast, the Vg uptake was markedly inhibited by JH while stimulating effect of the ecdysteroid could be shown that vitellin (Vt) titer in the ovary was lower after methoprene treatments, but higher after 20-hydroxyecdyson treatments. Meanwhile, effects of these two hormones on Vg synthesis in the fat body were also tested with the incubation in vitro with Grace medium containing H-leucine and the hormones. The results demonstrated that Vg synthesis was stimulated after treating with methoprene alone or 20-hydroxyecdysone alone and combined treating with these two chemicals, and particularly ecdysteroid had more marked positive effect. To comprehensively concluded our results, it could be regarded that ecdysteroid play the main role in the regulation of vitellogenesis for the Japanese oak silkworm. [source] An unusual association of pemphigus vulgaris with hyperprolactinemiaINTERNATIONAL JOURNAL OF DERMATOLOGY, Issue 10 2002MNAMS, Sujay Khandpur MD A 21-year-old unmarried woman presented with oral ulcerations and generalized, itchy, fluid-filled, skin lesions of 10 days' duration. The lesions ruptured spontaneously, resulting in extensive denuded areas covered by crusts. One month prior to this, she experienced pain and enlargement of both breasts with galactorrhea. Her menstrual cycles were normal initially, but later she developed menstrual irregularities. No past history suggestive of any other systemic or skin disease, including atopy or drug allergies, could be obtained. Her family history was not contributory. Dermatologic examination revealed multiple, flaccid bullae and extensive denuded areas of skin covered with crusts over the scalp, face, trunk, and upper and lower limbs (Fig. 1). Bulla spread sign and Nikolsky's sign were positive. The oral mucosa, including the lips, buccal surface, tongue, and palate, showed multiple erosions covered with necrotic slough. The rest of the mucocutaneous and systemic examination was within normal limits. Figure 1. Extensive erosions and flaccid bullae over the trunk with breast enlargement The patient's diagnostic work-up revealed: hemoglobin, 11.2 g%; total leukocyte count, 7400/mm3; differential leukocyte count, P62L34E2M2; erythrocyte sedimentation rate, 34 mm/h. A peripheral blood smear examination, urinalysis, blood sugar, and renal and liver function tests were normal. Venereal Disease Research Laboratory (VDRL) test and enzyme-linked immunoabsorbent assay (ELISA) for human immunodeficiency virus (HIV) were nonreactive. Antinuclear antibody, lupus erythematosus (LE) cell, rheumatoid factor, and anti-dsDNA levels were normal. Serum protein electrophoresis demonstrated increased levels of immunoglobulin G (IgG) antibody. The serum prolactin level was significantly raised to 139.49 ng/mL (normal, 3.6,18.9 ng/mL). The sex hormone levels, however, including follicle-stimulating hormone (FSH), luteinizing hormone (LH), estradiol, and progesterone, were within normal limits. The thyroid hormone profile was also unaltered. Chest X-ray was normal. Ultrasound of the abdomen and pelvis revealed no visceral abnormality and computerized tomography (CT) scan of the pituitary sella showed no adenoma. Mammography was negative for breast malignancy. A Tzanck smear prepared from the base of the erosion showed multiple acantholytic cells and lymphocytes. Histologic examination from an intact vesicle was suggestive of pemphigus vulgaris (PV), showing a suprabasal cleft with acantholytic cells and the basal layer demonstrating a "row of tombstones" appearance (Fig. 2). Direct immunofluorescence (DIF) revealed the intercellular deposition of IgG and C3 throughout the epidermis in a "fishnet pattern." Indirect immunofluorescence (IIF) test performed on rat esophagus for circulating IgG antibody was positive in a titer of 1 : 120. Figure 2. Photomicrograph showing suprabasal cleft with "row of tombstones" appearance, suggestive of pemphigus vulgaris (hematoxylin and eosin, × 40) Based on the clinical and immunohistological features, a diagnosis of PV with idiopathic hyperprolactinemia was made. The patient was treated with bromocriptine mesylate (Tablet Proctinal, Glaxo Wellcome Ltd, India) at a dose of 2.5 mg twice a day. After 2 months of therapy, significant improvement in the skin lesions was observed. The existing lesions re-epithelialized with a drastic reduction in the number and distribution of new vesicles. However, no change in the mucosal erosions was noticed. IIF test demonstrated a lower antibody titer (1 : 40). The breast complaints also improved with a reduction in serum prolactin level to 6.5 ng/mL. The patient refused further treatment as she experienced nausea and dizziness with bromocriptine. After 2 weeks, the disease relapsed with the appearance of new vesicles over the forearms, abdomen, back, and thighs. She again complained of breast tenderness and galactorrhea, and the serum prolactin level was 95 ng/mL. The IgG titer increased to 1 : 120. Hence, treatment with oral prednisolone (2 mg/kg/day) and bromocriptine (2.5 mg twice a day) with an antiemetic was initiated. After 6 weeks, the skin lesions had cleared completely, the breast symptoms had improved, menses had become regular, and the prolactin level had decreased to 4 ng/mL. IIF test was negative for circulating antibody. Steroids were tapered off and maintenance therapy with bromocriptine at a dose of 2.5 mg/day was continued. [source] | ||||||||||||||||||||||||||||||||||||||||