bluuebunny/crossref_metadata_2025_split huggingface dataset:
An Immunoglobulin G1 Monoclonal Antibody Highly Specific to the Wall of
Cryptosporidium
Oocysts
Authors: Weir C. , Vesey G. , Slade M. , Ferrari B. , Veal D. A. , Williams K. 
Published: July 2002

ABSTRACT

The detection of
Cryptosporidium
oocysts in drinking water is critically dependent on the quality of immunofluorescent reagents. Experiments were performed to develop a method for producing highly specific antibodies to
Cryptosporidium
oocysts that can be used for water testing. BALB/c mice were immunized with six different antigen preparations and monitored for immunoglobulin G (IgG) and IgM responses to the surface of
Cryptosporidium
oocysts. One group of mice received purified oocyst walls, a second group received a soluble protein preparation extracted from the outside of the oocyst wall, and the third group received whole inactivated oocysts. Three additional groups were immunized with sequentially prepared oocyst extracts to provide for a comparison of the immune response. Mice injected with the soluble protein extract demonstrated an IgG response to oocysts surface that was not seen in the whole-oocyst group. Mice injected with whole oocysts showed an IgM response only, while mice injected with purified oocyst walls showed little increase in IgM or IgG levels. Of the additional reported preparations only one, BME (2-mercaptoethanol treated), produced a weak IgM response to the oocyst wall. A mouse from the soluble oocyst extract group yielding a high IgG response was utilized to produce a highly specific IgG
1
monoclonal antibody (Cry104) specific to the oocyst surface. Comparative flow cytometric analysis indicated that Cry104 has a higher avidity and specificity to oocysts in water concentrates than other commercially available antibodies.
High Prevalence of
Helicobacter pylori
in the Alaska Native Population and Association with Low Serum Ferritin Levels in Young Adults
Authors: Parkinson Alan J. , Gold Benjamin D. , Bulkow Lisa , Wainwright Robert B. , Swaminathan Balasubra , Khanna Bhawna , Petersen Kenneth M. , Fitzgerald Mary Anne 
Published: July 2002

ABSTRACT

Iron deficiency anemia is a common public health problem in the Alaska Native population. Yet, a clear etiology has eluded researchers for decades. Previous studies suggested a link between
Helicobacter pylori
infection, gastrointestinal blood loss due to hemorrhagic gastritis, and generalized iron deficiency anemia in adult Alaska Natives. Therefore, we examined the association between the prevalence of
H. pylori
-specific immunoglobulin G (IgG) and serum ferritin levels, a marker of iron deficiency. A random sample of 2,080 serum samples from Alaska Native residents drawn between 1980 and 1986 from residents in 13 regions was selected, and the samples were stratified by age, sex, and region. Overall, 75% were positive for
H. pylori
-specific IgG. The rate of
H. pylori
seropositivity increased with age; by age 14 years, 78% of the residents were positive. There were no gender differences in
H. pylori
seropositivity. However, marked regional differences were observed. Serum ferritin levels of <12 ng/ml were found most commonly among persons <20 years of age and among women of childbearing age. A significant association between low serum ferritin levels and prevalence of
H. pylori
-specific IgG was found, particularly for people aged less than 20 years.
H. pylori
may be a factor contributing to the iron deficiency anemia in the Alaska Native population.
Presence of Human T-Cell Responses to theMycobacterium leprae45-Kilodalton Antigen Reflects Infection with or Exposure toM. leprae
Authors: Macfarlane Anne , Mondragon-Gonzalez Rafael , Vega-Lopez Francisco , Wieles Brigitte , de Pena Josefina , Rodriguez Obdulia , Suarez y de la Torre Raul , de Vries Rene R. P. , Ottenhoff Tom H. M. , Dockrell Hazel M. 
Published: July 2002

ABSTRACTThe ability of the 45-kDa serine-richMycobacterium lepraeantigen to stimulate peripheral blood mononuclear cell (PBMC) proliferation and gamma interferon (IFN-γ) production was measured in leprosy patients, household contacts, and healthy controls from areas of endemicity in Mexico. Almost all the tuberculoid leprosy patients gave strong PBMC proliferation responses to theM. leprae45-kDa antigen (92.8%;n= 14). Responses were lower in lepromatous leprosy patients (60.6%;n= 34), but some responses to the 45-kDa antigen were detected in patients unresponsive toM. lepraesonicate. The proportion of positive responses to theM. leprae45-kDa antigen was much higher in leprosy contacts (88%;n= 17) than in controls from areas of endemicity (10%;n= 20). None of 15 patients with pulmonary tuberculosis gave a positive proliferation response to the 45-kDa antigen. The 45-kDa antigen induced IFN-γ secretion similar to that induced by the nativeMycobacterium tuberculosis30/31-kDa antigen in tuberculoid leprosy patients and higher responses than those induced by the other recombinant antigens (M. leprae10- and 65-kDa antigens, thioredoxin, and thioredoxin reductase); in patients with pulmonary tuberculosis it induced lower IFN-γ secretion than the other recombinant antigens. These results suggest that theM. leprae45-kDa antigen is a potent T-cell antigen which isM. lepraespecific in these Mexican donors. This antigen may therefore have diagnostic potential as a new skin test reagent or as an antigen in a simple whole-blood cytokine test.
groEL
Encodes a Highly Antigenic Protein in
Burkholderia pseudomallei
Authors: Woo Patrick C. Y. , Leung Patricia K. L. , Wong Samson S. Y. , Ho Pak-Leung , Yuen Kwok-Yung 
Published: July 2002

ABSTRACT

No recombinant protein is available for serodiagnosis of melioidosis. In this study, we report the cloning of the
groEL
gene, which encodes an immunogenic protein of
Burkholderia pseudomallei
. Bidirectional DNA sequencing of
groEL
revealed that the gene contained a single open reading frame encoding 546 amino acid residues with a predicted molecular mass of 57.1 kDa. Basic Local Alignment Search Tool analysis showed that the putative protein encoded by
groEL
is homologous to the chaperonins encoded by the
groEL
genes of other bacteria. It has 98% amino acid identity with the GroEL of
Burkholderia cepacia,
98% amino acid identity with the GroEL of
Burkholderia vietnamiensis,
and 82% amino acid identity with the GroEL of
Bordetella pertussis
. Furthermore, it was observed that patients with melioidosis develop a strong antibody response against GroEL, suggesting that the recombinant protein and its monoclonal antibody may be useful for serodiagnosis in patients with melioidosis and that the protein may represent a good cell surface target for host humoral immunity. Further studies in these directions would be warranted.
Recognition of Multiple Classes of Hepatitis C Antibodies Increases Detection Sensitivity in Oral Fluid
Authors: Zmuda Jonathan F. , Wagoneer Barbara , Liotta Lance , Whiteley Gordon 
Published: July 2002

ABSTRACT
Paired serum-oral fluid samples from 127 hepatitis C virus (HCV)-positive and 31 HCV-negative patients were tested for the presence of anti-HCV using the Ortho HCV 3.0 ELISA. Using the immunoglobulin G (IgG)-specific detection antibody provided with the HCV 3.0 ELISA we attained 100% sensitivity and specificity with serum samples; however, sensitivity in oral fluid samples was only 81%. By modifying the HCV 3.0 ELISA to utilize a secondary antibody cocktail that recognizes not only IgG but IgA and IgM as well, we attained 100% specificity and sensitivity with oral fluid samples.
Increased Levels of Inflammatory Mediators in Children and Adults Infected withVibrio choleraeO1 and O139
Authors: Qadri Firdausi , Raqib Rubhana , Ahmed Firoz , Rahman Taufiqur , Wenneras Christine , Kumar Das Swadesh , Alam Nur Haque , Mathan Minnie M. , Svennerholm Ann-Mari 
Published: July 2002

ABSTRACTInvestigations were carried out to study the production of factors associated with the innate immune response in the systemic and mucosal compartments in adults and children infected withVibrio choleraeO1 andV. choleraeO139. The levels of nonspecific mediators of the innate defense system, i.e., prostaglandin E2(PGE2), leukotriene B4(LTB4), and lactoferrin (Lf), as well as myeloperoxidase (MPO), were elevated at the acute stage of the disease in stools obtained from both O1- and O139-infected adults and children. In the systemic compartment, the levels of Lf were increased after onset of disease, which in children remained elevated up to convalescence compared to the healthy controls. Increased concentrations of C-reactive protein were seen in the sera of adult cholera patients at the acute stage of infection. Elevated levels of the nitric oxide (NO·) metabolites (nitrite and nitrate [NO2−and NO3−]) were detected in plasma but not in urine. The activity of the scavenger of reactive oxygen species, superoxide dismutase, was higher in the plasma of adults immediately after the onset of disease, suggesting that an active scavenging of reactive oxygen species was taking place. The concentration of 8-iso-prostaglandin F2αremained unchanged in the systemic and mucosal compartments in the study subjects. After the recovery of patients from cholera, the concentration of the majority of the metabolites decreased to baseline levels by day 30 after the onset of infection. Immunohistochemical staining showed increased tissue expression of MPO, Lf, and inducible nitric oxide synthase at the acute stage in the duodenal biopsies of adults and rectal biopsies obtained from children with cholera. Very little difference was seen in the levels of the different inflammatory mediators in patients infected withV. choleraeO1 or the encapsulatedV. choleraeO139. In summary, these results suggest that elevated concentrations of Lf, MPO, PGE2, LTB4, and NO·, as well as other metabolites, during the acute stage of the disease indicate that the innate defense system, as well as the inflammatory process, is activated in both adults and pediatric patients infected withV. choleraeO1 and O139.
Sensitive and Specific Identification ofNeospora caninumInfection of Cattle Based on Detection of Serum Antibodies to Recombinant Ncp29
Authors: Howe Daniel K. , Tang Keliang , Conrad Patricia A. , Sverlow Karen , Dubey J. P. , Sibley L. David 
Published: July 2002

ABSTRACTNeosporosis is an economically important disease of dairy cattle caused by the protozoanNeospora caninum. Diagnostic tests for neosporosis are complicated by the potential for cross-reaction of antibodies to antigens that are similar betweenN. caninumand closely related parasitesToxoplasma gondiiandSarcocystis cruzi.To provide a sensitive and specific assay for detecting antibodies toN. caninumin the serum of infected animals, we have investigated a recombinant form of the antigen known as Ncp29 (rNcp29), which is a major surface protein of the parasite. Ncp29 is encoded by a gene that is homologous to theSAG1gene previously characterized fromT. gondii.An enzyme-linked immunosorbent assay (ELISA) was used to screen animals for the presence of serum antibodies specific to rNcp29. The rNcp29 ELISA readily distinguished between cattle known to be infected withN. caninum(optical density [OD] > 1.2 at 1:500 or greater dilution) and negative controls (OD < 0.5 at 1:500). Additionally, sera from animals that were infected withT. gondiiorS. cruziwere negative. The rNcp29 ELISA developed here provides a specific and sensitive assay for detecting neosporosis in cattle.
Infection of Tick Cells and Bovine Erythrocytes with One Genotype of the Intracellular EhrlichiaAnaplasma marginaleExcludes Infection with Other Genotypes
Authors: de la Fuente José , Garcia-Garcia Jose C. , Blouin Edmour F. , Saliki Jeremiah T. , Kocan Katherine M. 
Published: July 2002

ABSTRACTAnaplasma marginale,a tick-borne rickettsial pathogen of cattle, is endemic in several areas of the United States. Many geographic isolates ofA. marginalethat occur in the United States are characterized by the major surface protein 1a, which varies in sequence and molecular weight due to different numbers of tandem repeats of 28 or 29 amino acids. Recent studies (G. H. Palmer, F. R. Rurangirwa, and T. F. McElwain, J. Clin. Microbiol. 39:631-635, 2001) of anA. marginale-infected herd of cattle in an area of endemicity demonstrated that multiplemsp1αgenotypes were present but that only one genotype was found per individual bovine. These findings suggested that infection of cattle with other genotypes was excluded. The present study was undertaken to confirm the phenomenon of infection exclusion ofA. marginalegenotypes in infected bovine erythrocytes and cultured tick cells. Two tick-transmissible isolates ofA. marginale, one from Virginia and one from Oklahoma, were used for these studies. In two separate trials, cattle inoculated with equal doses of the two isolates developed infection with only one genotype. Tick cell cultures inoculated with equal doses of the two isolates became infected with only the Virginia isolate ofA. marginale. When cultures were inoculated with different ratios of the Oklahoma and Virginia isolates ofA. marginale, the isolate inoculated in the higher ratio became established and excluded infection with the other. When cultures with established infections of one isolate were subsequently infected with the other, only the established isolate was detected. We documented infection exclusion during initial infection in cell culture by labeling each isolate with a different fluorescent dye. After 2 days in culture, only a single isolate was detected per cell by fluorescence microscopy. Finally, whenAnaplasma ovisinfections were established in cultures that were subsequently inoculated with the Virginia or Oklahoma isolate ofA. marginale,A. marginaleinfection was excluded. These studies confirm that infection exclusion occurs withA. marginalein bovine erythrocytes and tick cells, resulting in the establishment of only one genotype, and appears to be the first report of infection exclusion forAnaplasmaandEhrlichiaspecies.
Analysis of Human Antibodies to Erythrocyte Binding Antigen 175 of
Plasmodium falciparum
Authors: Okenu Daniel M. N. , Riley Eleanor M. , Bickle Quentin D. , Agomo Philip U. , Barbosa Arnoldo , Daugherty Jon R. , Lanar David E. , Conway David J. 
Published: July 2002

ABSTRACT

Invasion of human erythrocytes by
Plasmodium falciparum
merozoites is a multistep process. For many strains of the parasite, part of this process requires that the erythrocyte binding antigen 175 (EBA-175) of the merozoite binds to sialic acid residues of glycophorin A on the erythrocyte surface, a receptor-ligand interaction which represents a potential target for inhibition by antibodies. This study characterizes the reactivity of naturally acquired human antibodies with four recombinant proteins representing parts of EBA-175 (region II, regions III to V, and the dimorphic C and F segment region) in populations in which the organism is endemic. Serum immunoglobulin G (IgG) recognizing the recombinant proteins is predominantly of the IgG1 and IgG3 subclasses, and its prevalence increases with age. In a large population study in The Gambia, serum positivity for IgG or IgG1 and IgG3 subclass antibodies to each of the EBA-175 recombinant antigens was not significantly associated with subsequent protection from clinical malaria. However, there was a trend indicating that individuals with high levels of IgG to region II may have some protection.
Interleukin 12 as an Adjuvant to WI-1 Adhesin Immunization Augments Delayed-Type Hypersensitivity, Shifts the Subclass Distribution of Immunoglobulin G Antibodies, and Enhances Protective Immunity toBlastomyces dermatitidisInfection
Authors: Wüthrich Marcel , Finkel-Jiminez Beatriz E. , Klein Bruce S. 
Published: July 2002

ABSTRACTCell-mediated immunity is pivotal in host resistance toBlastomyces dermatitidisinfection. Immunization of mice with the WI-1 adhesin enhances resistance against experimental pulmonary infection but elicits features of a mixed T-helper-cell immune response. Immune mice acquire delayed-type hypersensitivity (DTH) but also high titers of WI-1-specific immunoglobulin G1 (IgG1) and IgG2b, a result indicative of T-helper-2 cellular immunity. We report that interleukin-12, used as an adjuvant for WI-1 immunization, augments DTH, shifts the balance of the T-helper phenotype toward Th1, and enhances resistance toB. dermatitidisinfection.
Bacterial Induction of Beta Interferon in Mice Is a Function of the Lipopolysaccharide Component
Authors: Sing Andreas , Merlin Thomas , Knopf Hans-Peter , Nielsen Peter J. , Loppnow Harald , Galanos Chris , Freudenberg Marina A. 
Published: July 2002

ABSTRACTWe investigated the reason for the inability of lipopolysaccharide (LPS)-resistant (Lps-defective [Lpsd]) C57BL/10ScCr mice to produce beta interferon (IFN-β) when stimulated with bacteria. For this purpose, the IFN-β and other macrophage cytokine responses induced by LPS and several killed gram-negative and gram-positive bacteria in LPS-sensitive (Lps-normal [Lpsn]; C57BL/10ScSn and BALB/c) andLpsd(C57BL/10ScCr and BALB/c/l) mice in vitro and in vivo were investigated on the mRNA and protein levels. In addition, double-stranded RNA (dsRNA) was used as a nonbacterial stimulus. LPS and all gram-negative bacteria employed induced IFN-β in theLpsnmice but not in theLpsdmice. All gram-positive bacteria tested failed to induce significant amounts of IFN-β in all four of the mouse strains used. As expected, all other cytokines tested (tumor necrosis factor alpha, interleukin 1α [IL-1α], IL-6, and IL-10) were differentially induced by gram-negative and gram-positive bacteria. Stimulation with dsRNA induced IFN-β and all other cytokines mentioned above in all mouse strains, regardless of their LPS sensitivities. The results suggest strongly that LPS is the only bacterial component capable of inducing IFN-β in significant amounts that are readily detectable under the conditions used in this study. Consequently, in mice, IFN-β is inducible only by gram-negative bacteria, but not in C57BL/10ScCr or other LPS-resistant mice.
Comparative Genome Analysis of the Pathogenic Spirochetes
Borrelia burgdorferi
and
Treponema pallidum
Authors: Subramanian G. , Koonin Eugene V. , Aravind L. 
Published: July 2002

ABSTRACT

A comparative analysis of the predicted protein sequences encoded in the complete genomes of
Borrelia burgdorferi
and
Treponema pallidum
provides a number of insights into evolutionary trends and adaptive strategies of the two spirochetes. A measure of orthologous relationships between gene sets, termed the orthology coefficient (OC), was developed. The overall OC value for the gene sets of the two spirochetes is about 0.43, which means that less than one-half of the genes show readily detectable orthologous relationships. This emphasizes significant divergence between the two spirochetes, apparently driven by different biological niches. Different functional categories of proteins as well as different protein families show a broad distribution of OC values, from near 1 (a perfect, one-to-one correspondence) to near 0. The proteins involved in core biological functions, such as genome replication and expression, typically show high OC values. In contrast, marked variability is seen among proteins that are involved in specific processes, such as nutrient transport, metabolism, gene-specific transcription regulation, signal transduction, and host response. Differences in the gene complements encoded in the two spirochete genomes suggest active adaptive evolution for their distinct niches. Comparative analysis of the spirochete genomes produced evidence of gene exchanges with other bacteria, archaea, and eukaryotic hosts that seem to have occurred at different points in the evolution of the spirochetes. Examples are presented of the use of sequence profile analysis to predict proteins that are likely to play a role in pathogenesis, including secreted proteins that contain specific protein-protein interaction domains, such as von Willebrand A, YWTD, TPR, and PR1, some of which hitherto have been reported only in eukaryotes. We tentatively reconstruct the likely evolutionary process that has led to the divergence of the two spirochete lineages; this reconstruction seems to point to an ancestral state resembling the symbiotic spirochetes found in insect guts.
Identification of Potential Vaccine and Drug Target Candidates by Expressed Sequence Tag Analysis and Immunoscreening ofOnchocerca volvulusLarval cDNA Libraries
Authors: Lizotte-Waniewski Michelle , Tawe Wilson , Guiliano David B. , Lu Wenhong , Liu Jing , Williams Steven A. , Lustigman Sara 
Published: July 2002

ABSTRACTThe search for appropriate vaccine candidates and drug targets against onchocerciasis has so far been confronted with several limitations due to the unavailability of biological material, appropriate molecular resources, and knowledge of the parasite biology. To identify targets for vaccine or chemotherapy development we have undertaken two approaches. First, cDNA expression libraries were constructed from life cycle stages that are critical for establishment ofOnchocerca volvulusinfection, the third-stage larvae (L3) and the molting L3. A gene discovery effort was then initiated by random expressed sequence tag analysis of 5,506 cDNA clones. Cluster analyses showed that many of the transcripts were up-regulated and/or stage specific in either one or both of the cDNA libraries when compared to the microfilariae, L2, and both adult stages of the parasite. Homology searches against the GenBank database facilitated the identification of several genes of interest, such as proteinases, proteinase inhibitors, antioxidant or detoxification enzymes, and neurotransmitter receptors, as well as structural and housekeeping genes. OtherO. volvulusgenes showed homology only to predicted genes from the free-living nematodeCaenorhabditis elegansor were entirely novel. Some of the novel proteins contain potential secretory leaders. Secondly, by immunoscreening the molting L3 cDNA library with a pool of human sera from putatively immune individuals, we identified six novel immunogenic proteins that otherwise would not have been identified as potential vaccinogens using the gene discovery effort. This study lays a solid foundation for a better understanding of the biology ofO. volvulusas well as for the identification of novel targets for filaricidal agents and/or vaccines against onchocerciasis based on immunological and rational hypothesis-driven research.