bluuebunny/crossref_metadata_2025_split huggingface dataset:
Promising Multiple-Epitope Recombinant Vaccine against Foot-and-Mouth Disease Virus Type O in Swine
Authors: Shao Jun-Jun , Wong Chung Kai , Lin Tong , Lee Shuk Kwan , Cong Guo-Zheng , Sin Fion Wai Yee , Du Jun-Zheng , Gao Shan-Dian , Liu Xiang-Tao , Cai Xue-Peng , Xie Yong , Chang Hui-Yun , Liu Ji-Xing 
Published: November 2010

ABSTRACTIn order to develop a completely safe immunogen to replace the traditional inactivated vaccine, a tandem-repeat multiple-epitope recombinant vaccine against foot-and-mouth disease (FMD) virus (FMDV) type O was developed. It contained three copies each of residues 141 to 160 and 200 to 213 of VP1 of the O/China/99 strain of FMDV coupled with a swine immunoglobulin G heavy-chain constant region (scIgG). The data showed that the multiple-epitope recombinant vaccine elicited high titers of anti-FMDV specific antibodies in swine at 30 days postvaccination (dpv) and conferred complete protection against a challenge with 10350% swine infective doses of the O/China/99 strain. The anti-FMDV specific antibody titers were not significantly different between the multiple-epitope recombinant vaccine and the traditional vaccine (ttest,P> 0.05). The number of 50% pig protective doses was 6.47, which is higher than the number recommended by the World Organization for Animal Health. The multiple-epitope recombinant vaccine resulted in a duration of immunity of at least 6 months. We speculate that the multiple-epitope recombinant vaccine is a promising vaccine that may replace the traditional inactivated vaccine for the prevention and control of FMD in swine in the future.
Human Leukocyte Antigens A*3001 and A*3002 Show Distinct Peptide-Binding Patterns of theMycobacterium tuberculosisProtein TB10.4: Consequences for Immune Recognition
Authors: Axelsson-Robertson Rebecca , Ahmed Raija K. , Weichold Frank F. , Ehlers Marthie M. , Kock Marleen M. , Sizemore Donata , Sadoff Jerry , Maeurer Markus 
Published: November 2010

ABSTRACTHigh-tuberculosis (TB)-burden countries are located in sub-Saharan Africa. We examined the frequency of human leukocyte antigen (HLA) alleles, followed by recombinant expression of the most frequent HLA-A alleles, i.e., HLA-A*3001 and HLA-A*3002, to study differences in mycobacterial peptide presentation and CD8+T-cell recognition. We screened a peptide library (9-mer peptides with an 8-amino-acid overlap) for binding, affinity, and off-rate of theMycobacterium tuberculosis-associated antigen TB10.4 and identified only three TB10.4 peptides with considerable binding to HLA-A*3001. In contrast, 22 peptides bound to HLA-A*3002. This reflects a marked difference in the binding preference between the two alleles, with A*3002 tolerating a more promiscuous peptide-binding pattern and A*3001 accommodating only a very selective peptide repertoire. Subsequent analysis of the affinity and off-rate of the binding peptides revealed a strong affinity (8 nM to 7 μM) and moderate off-rate (20 min to 3 h) for both alleles. Construction of HLA-A*3001 and HLA-A*3002 tetramers containing selected binding peptides from TB10.4, including a peptide which was shared among both alleles, QIMYNYPAM (TB10.43-11), allowed us to enumerate epitope-specific T cells in HLA-A*3001- and HLA-A*3002-typed patients with active TB. HLA-A*3001 and HLA-A*3002 major histocompatibility complex-peptide complexes were recognized in individuals with active TB, irrespective of their homozygous HLA-A*3001 or HLA-A*3002 genetic background. The antigen-specific T cells exhibited the CD45RA+CCR7+precursor phenotype and the interleukin-7 receptor (CD127), which were different from the phenotype and receptor exhibited by the parental CD8+T-cell population.
Sublingual Administration of an Adenovirus Serotype 5 (Ad5)-Based Vaccine Confirms Toll-Like Receptor Agonist Activity in the Oral Cavity and Elicits Improved Mucosal and Systemic Cell-Mediated Responses against HIV Antigens despite Preexisting Ad5 Immunity
Authors: Appledorn Daniel M. , Aldhamen Yasser A. , Godbehere Sarah , Seregin Sergey S. , Amalfitano Andrea 
Published: November 2010

ABSTRACT

HIV/AIDS continue to devastate populations worldwide. Recent studies suggest that vaccines that induce beneficial immune responses in the mucosal compartment may improve the efficacy of HIV vaccines. Adenovirus serotype 5 (Ad5)-based vectors remain a promising platform for the development of effective vaccines. In an effort to improve the efficacy of Ad5-based vaccines, even in the presence of preexisting Ad5 immunity, we evaluated the potential for an Ad5-based HIV vaccine to induce antigen-specific immune responses following sublingual (s.l.) administration, a route not previously tested in regard to Ad-based vaccines. s.l. vaccination with an Ad5-based HIV-Gag vaccine resulted in a significant induction of Gag-specific cytotoxic T-lymphocyte (CTL) responses in both the systemic and the mucosal compartment. We also show that s.l. immunization not only avoided preexisting Ad5 immunity but also elicited a broad repertoire of antigen-specific CTL clones. Additionally, we confirm for the first time that oral delivery of a vaccine expressing a potent Toll-like receptor (TLR) agonist can stimulate innate immune responses through induction of cytokines and chemokines and activation of NK cells, NKT cells, and macrophages
in vivo
. These results positively correlated with improved antigen-specific CTL responses. These results could be achieved both in Ad5-naïve mice and in mice with preexisting immunity to Ad5. The simplicity of the s.l. vaccination regimen coupled with augmentation of TLR-dependent pathways active in the oral cavity makes s.l. delivery a promising method for HIV vaccine development specifically, as well as for many other vaccine applications in general.
Differentiation between Human Coronaviruses NL63 and 229E Using a Novel Double-Antibody Sandwich Enzyme-Linked Immunosorbent Assay Based on Specific Monoclonal Antibodies
Authors: Sastre Patricia , Dijkman Ronald , Camuñas Ana , Ruiz Tamara , Jebbink Maarten F. , van der Hoek Lia , Vela Carmen , Rueda Paloma 
Published: November 2010

ABSTRACTHuman coronaviruses (HCoVs) are responsible for respiratory tract infections ranging from common colds to severe acute respiratory syndrome. HCoV-NL63 and HCoV-229E are two of the four HCoVs that circulate worldwide and are close phylogenetic relatives. HCoV infections can lead to hospitalization of children, elderly individuals, and immunocompromised patients. Globally, approximately 5% of all upper and lower respiratory tract infections in hospitalized children are caused by HCoV-229E and HCoV-NL63. The latter virus has recently been associated with the childhood disease croup. Thus, differentiation between the two viruses is relevant for epidemiology studies. The aim of this study was to develop a double-antibody sandwich enzyme-linked immunosorbent assay (DAS-ELISA) as a potential tool for identification and differentiation between HCoV-NL63 and HCoV-229E. The nucleocapsid (N) proteins of HCoV-NL63 and HCoV-229E were expressed in anEscherichia colisystem and used to immunize mice in order to obtain monoclonal antibodies (MAbs) specific for each virus. Three specific MAbs to HCoV-NL63, one MAb specific to HCoV-229E, and four MAbs that recognized both viruses were obtained. After their characterization, three MAbs were selected in order to develop a differential DAS-ELISA. The described assay could detect up to 3 ng/ml of N protein and 50 50% tissue culture infective doses/ml of virus stock. No cross-reactivity with other human coronaviruses or closely related animal coronaviruses was found. The newly developed DAS-ELISA was species specific, and therefore, it could be considered a potential tool for detection and differentiation of HCoV-NL63 and HCoV-229E infections.
Multilaboratory Comparison of
Streptococcus pneumoniae
Opsonophagocytic Killing Assays and Their Level of Agreement for the Determination of Functional Antibody Activity in Human Reference Sera
Authors: Rose Charles E. , Romero-Steiner Sandra , Burton Robert L. , Carlone George M. , Goldblatt David , Nahm Moon H. , Ashton Lindsey , Haston Mitch , Ekström Nina , Haikala Raili , Käyhty Helena , Henckaerts Isabelle , Durant Nathalie , Poolman Jan T. , Fernsten Phil , Yu Xinhong , Hu Branda T. , Jansen Kathrin U. , Blake Milan , Simonetti Elles R. , Hermans Peter W. M. , Plikaytis Brian D. 
Published: November 2010

ABSTRACT

Antibody-mediated killing of
Streptococcus pneumoniae
(pneumococcus) by phagocytes is an important mechanism of protection of the human host against pneumococcal infections. Measurement of opsonophagocytic antibodies by use of a standardized opsonophagocytic assay (OPA) is important for the evaluation of candidate vaccines and required for the licensure of new pneumococcal conjugate vaccine formulations. We assessed agreement among six laboratories that used their own optimized OPAs on a panel of 16 human reference sera for 13 pneumococcal serotypes. Consensus titers, estimated using an analysis-of-variance (ANOVA) mixed-effects model, provided a common reference for assessing agreement among these laboratories. Agreement was evaluated in terms of assay accuracy, reproducibility, repeatability, precision, and bias. We also reviewed four acceptance criterion intervals for assessing the comparability of protocols when assaying the same reference sera. The precision, accuracy, and concordance results among laboratories and the consensus titers revealed acceptable agreement. The results of this study indicate that the bioassays evaluated in this study are robust, and the resultant OPA values are reproducible for the determination of functional antibody titers specific to 13 pneumococcal serotypes when performed by laboratories using highly standardized but not identical assays. The statistical methodologies employed in this study may serve as a template for evaluating future multilaboratory studies.
Promoter Discrimination at Class I MarA Regulon Promoters Mediated by Glutamic Acid 89 of the MarA Transcriptional Activator ofEscherichia coli
Authors: Martin Robert G. , Rosner Judah L. 
Published: November 2010

ABSTRACTThree paralogous transcriptional activators MarA, SoxS, and Rob, activate >40Escherichia colipromoters. To understand why MarA does not activate certain promoters as strongly as SoxS, we compared MarA, MarA mutants, and SoxS for their abilities to activate 16 promoters and to bind their cognate marbox binding sites. Replacement of the MarA glutamic acid residue 89 with alanine greatly increased the marbox binding and activation of many class I promoters. Like cells constitutive for SoxS, cells expressing the MarA with the E89A mutation were more resistant to superoxides than those harboring WT MarA. The activities of several other E89 substitutions ranked as follows: E89A > E89G > E89V > WT > E89D. Increased binding and activation occurred only at class I promoters when the 12th base of the promoter's marbox (a position at which there is no known interaction between the marbox and MarA) was not a T residue. Furthermore, WT MarA binding to a synthetic marboxin vitrowas enhanced when the phosphate group between positions 12 and 13 was eliminated on one strand. The results demonstrate that relatively minor changes in a single amino acid side chain (e.g., alanine to valine or glutamic acid to aspartic acid) can strongly influence activity despite any evidence that the side chain is involved in positive interactions with either DNA or RNA polymerase. We present a model which attributes the differences in binding and activation to the interference between the β- and γ-carbons of the amino acid at position 89 and the phosphate group between positions 12 and 13.
Spatial Regulation of Histidine Kinases Governing Biofilm Formation inBacillus subtilis
Authors: McLoon Anna L. , Kolodkin-Gal Ilana , Rubinstein Shmuel M. , Kolter Roberto , Losick Richard 
Published: November 2010

ABSTRACTBacillus subtilisis able to form architecturally complex biofilms on solid medium due to the production of an extracellular matrix. A master regulator that controls the expression of the genes involved in matrix synthesis is Spo0A, which is activated by phosphorylation via a phosphorelay involving multiple histidine kinases. Here we report that four kinases, KinA, KinB, KinC, and KinD, help govern biofilm formation but that their contributions are partially masked by redundancy. We show that the kinases fall into two categories and that the members of each pair (one pair comprising KinA and KinB and the other comprising KinC and KinD) are partially redundant with each other. We also show that the kinases are spatially regulated: KinA and KinB are active principally in the older, inner regions of the colony, and KinC and KinD function chiefly in the younger, outer regions. These conclusions are based on the morphology of kinase mutants, real-time measurements of gene expression using luciferase as a reporter, and confocal microscopy using a fluorescent protein as a reporter. Our findings suggest that multiple signals from the older and younger regions of the colony are integrated by the kinases to determine the overall architecture of the biofilm community.
Altered Regulation of the OmpF Porin by Fis inEscherichia coliduring an Evolution Experiment and between B and K-12 Strains
Authors: Crozat Estelle , Hindré Thomas , Kühn Lauriane , Garin Jérome , Lenski Richard E. , Schneider Dominique 
Published: November 2010

ABSTRACTThe phenotypic plasticity of global regulatory networks provides bacteria with rapid acclimation to a wide range of environmental conditions, while genetic changes in those networks provide additional flexibility as bacteria evolve across long time scales. We previously identified mutations in the global regulator-encoding genefisthat enhanced organismal fitness during a long-term evolution experiment withEscherichia coli. To gain insight into the effects of these mutations, we produced two-dimensional protein gels with strains carrying differentfisalleles, including a beneficial evolved allele and one with an in-frame deletion. We found that Fis controls the expression of the major porin-encoding geneompFin theE. coliB-derived ancestral strain used in the evolution experiment, a relationship that has not been described before. We further showed that this regulatory connection evolved over two different time scales, perhaps explaining why it was not observed before. On the longer time scale, we showed that this regulation ofompFby Fis is absent from the more widely studied K-12 strain and thus is specific to the B strain. On a shorter time scale, this regulatory linkage was lost during 20,000 generations of experimental evolution of the B strain. Finally, we mapped the Fis binding sites in theompFregulatory region, and we present a hypothetical model ofompFexpression that includes its other known regulators.
Comparison of the RealTime HIV-1, COBAS TaqMan 48 v1.0, Easy Q v1.2, and Versant v3.0 assays for Determination of HIV-1 Viral Loads in a Cohort of Canadian Patients with Diverse HIV Subtype Infections
Authors: Church Deirdre , Gregson Daniel , Lloyd Tracie , Klein Marina , Beckthold Brenda , Laupland Kevin , Gill M. John 
Published: November 2010

ABSTRACT

HIV clinics in Canada provide care to an increasing number of patients born outside of Canada with HIV-1 non-B subtype infections. Because the Easy Q HIV-1 v1.2 assay (EQ; bioMérieux) failed to detect some non-B subtype infections, a multiassay HIV-1 viral load (VL) study was conducted with patients with diverse HIV subtype infections. Patients were enrolled from the Southern Alberta HIV Clinic (SAC), Calgary, Alberta, Canada (
n
= 349) and the McGill HIV Clinic (MHC), Montreal, Quebec, Canada (
n
= 20) and had four or five tubes of blood drawn for testing by EQ and three other commercial HIV VL assays: (i) the Versant 3.0 HIV-1 test, with the Versant 440 instrument (branched DNA [bDNA]; Siemens), (ii) the RealTime HIV-1 test, with the
m
2000rt instrument (
m
2000rt; Abbott Molecular Diagnostics), and (iii) the COBAS AmpliPrep TaqMan HIV-1 48 test (CAP-CTM; Roche Molecular Diagnostics). Blood was processed according to the individual manufacturer's requirements and stored frozen at −86°C. The HIV subtype was known for patients who had undergone HIV genotypic resistance testing (Virco, Belgium). Data analyses were done using standard statistical methods within Stata 9.0 (StataCorp, College Station, TX). A total of 371 samples were tested on 369 patients, of whom 291 (81%) had a Virco genotype result of B (195; 53%) or non-B (96; 26%) subtypes A to D and F to K, as well as circulating recombinant forms (CRFs) (i.e., CRF01_AE and CRF02_AG). Most (58/78; 74%) patients of unknown subtype were recent African emigrants who likely have non-subtype B infection. Overall bias was small in pairwise Bland-Altman plots, but the limits of agreement between assays were wide. Discordant viral load results occurred for 98 samples and were due to missing values, false negatives, and significant underquantification that varied by HIV subtype. Results were obtained for all 371 samples with
m
2000rt, but for only 357 (97%) with CAP-CTM, 338 (92%) with EQ, and 276 (75%) with bDNA due to errors/equipment failures. False-negative results (nondetection of viral RNA versus other assay results) occurred for all platforms, as follows: for
m
2000rt, 8 (2%) [B(4) and non-B(4) subtypes], CAP-CTM, 9 (2.5%) [B(6) and non-B(3) subtypes]; EQ, 20 (6%) [B(7) and non-B(13) subtypes]; bDNA, 5 (2%) [B(1) and C(4)]. EQ and bDNA had the highest rates of underquantification by ≥1.0 log
10
copies/ml, mainly for HIV non-B subtypes. Performance significantly varied between HIV VL platforms according to subtype. HIV viral diversity in the population being tested must be considered in selection of the viral load platform.
Multiple-Locus Variable-Number Tandem Repeat Analysis of
Neisseria gonorrhoeae
Authors: Heymans Raymond , Schouls Leo M. , van der Heide Han G. J. , Schim van der Loeff Maarten F. , Bruisten Sylvia M. 
Published: November 2010

ABSTRACT

The prevalence of
Neisseria gonorrhoeae
in the Netherlands has increased in recent years. A multiple-locus variable-number tandem repeat analysis (MLVA) was developed to assess the molecular epidemiology of
N
.
gonorrhoeae
and to elucidate transmission networks in high-risk groups in Amsterdam. The MLVA was evaluated using 5 variable-number tandem repeat (VNTR) loci with various degrees of polymorphism that were amplified in 2 multiplex PCRs and were then separated and sized on an automated sequencer. The assessed number of repeats was used to create MLVA profiles that consisted of strings of 5 integers. The stability of the VNTR loci was assessed using isolates obtained from multiple anatomical locations from the same patient (
n
= 118) and from patients and their sexual partners (
n
= 55). When isolates with a single locus variant were considered to belong to the same MLVA type, 87% of samples from multiple anatomical locations and 88% of samples from sexual partners shared an MLVA type. MLVA was ultimately performed on 880 isolates that were previously genotyped by restriction fragment length polymorphism (RFLP) analysis of the
por-opa
genes. Hierarchical cluster analysis of the MLVA profiles from 716 patient visits (one anatomical location per visit) classified 430 patient visits into 14 larger clusters (≥10 patient visits). In 7 clusters, 81% to 100% of isolates came from men who have sex with men (MSM); in 5 clusters, 79% to 100% of isolates came from heterosexuals; and 2 clusters contained isolates from fully mixed populations. Clusters also differed in characteristics such as ethnic background and coinfections. MLVA provided accurate identification of genetically related
N. gonorrhoeae
strains and revealed clusters of MSM and heterosexuals reflecting distinct transmission networks.
Comparison of Three Molecular Techniques for Typing
Pseudomonas aeruginosa
Isolates in Sputum Samples from Patients with Cystic Fibrosis
Authors: Kidd Timothy J. , Grimwood Keith , Ramsay Kay A. , Rainey Paul B. , Bell Scott C. 
Published: November 2010

ABSTRACT

Monitoring the emergence and transmission of
Pseudomonas aeruginosa
strains among cystic fibrosis (CF) patients is important for infection control in CF centers internationally. A recently developed multilocus sequence typing (MLST) scheme is used for epidemiologic analyses of
P. aeruginosa
outbreaks; however, little is known about its suitability for isolates from CF patients compared with that of pulsed-field gel electrophoresis (PFGE) and enterobacterial repetitive intergenic consensus-PCR (ERIC-PCR). As part of a prevalence study of
P. aeruginosa
strains in Australian CF clinics, we compared the discriminatory power and concordance of ERIC-PCR, PFGE, and MLST among 93 CF sputum and 11 control
P. aeruginosa
isolates. PFGE and MLST analyses were also performed on 30 paired isolates collected 85 to 354 days apart from 30 patients attending two CF centers separated by 3,600 kilometers in order to detect within-host evolution. Each of the three methods displayed high levels of concordance and discrimination; however, overall lower discrimination was seen with ERIC-PCR than with MLST and PFGE. Analysis of the 50 ERIC-PCR types yielded 54 PFGE types, which were related by ≤6 band differences, and 59 sequence types, which were classified into 7 BURST groups and 42 singletons. MLST also proved useful for detecting novel and known strains and for inferring relatedness among unique PFGE types. However, 47% of the paired isolates produced PFGE patterns that within 1 year differed by one to five bands, whereas with MLST all paired isolates remained identical. MLST thus represents a categorical analysis tool with resolving power similar to that of PFGE for typing
P. aeruginosa
. Its focus on highly conserved housekeeping genes is particularly suited for long-term clinical monitoring and detecting novel strains.
Granulomatous Amebic Encephalitis in a Child with Acute Lymphoblastic Leukemia Successfully Treated with Multimodal Antimicrobial Therapy and Hyperbaric Oxygen
Authors: Maritschnegg P. , Sovinz P. , Lackner H. , Benesch M. , Nebl A. , Schwinger W. , Walochnik J. , Urban C. 
Published: November 2010

ABSTRACT

Acanthamoeba is the causative agent of granulomatous amebic encephalitis, a rare and usually fatal disease. We report a child with acute lymphoblastic leukemia who developed brain abscesses caused by
Acanthamoeba
during induction therapy. Multimodal antimicrobial chemotherapy and hyperbaric oxygen therapy resulted in complete resolution of symptoms and of pathology as seen by magnetic resonance imaging.