bluuebunny/crossref_metadata_2025_split huggingface dataset:
Use of Recombinant Flagellin Protein as a Tracer Antigen in a Fluorescence Polarization Assay for Diagnosis of Leptospirosis
Authors: Bughio Nasreen I. , Lin Min , Surujballi Om P. 
Published: December 2019

ABSTRACT

The objective of the present study was to investigate the usefulness of a recombinant flagellar protein, FlaB, of
Leptospira interrogans
serovar
pomona
in the serodiagnosis of leptospirosis by the fluorescence polarization assay (FPA). The recombinant protein FlaB was purified to homogeneity by a combination of nickel-nitriloacetic acid agarose chromatography, electrophoresis, and electroelution. Purified FlaB was labeled with fluorescein isothiocyanate (FITC). Western blotting was performed by using bovine sera with microscopic agglutination test (MAT) titers of antibodies against
L. interrogans
serovar
pomona
and
L. bergpetersenii
serovars
hardjo
and
sejroe
to confirm the antigenicity of FlaB. Western blot analysis demonstrated that labeled as well as unlabeled FlaB was recognized by the positive sera tested, indicating the broad serovar cross-reactivity of this protein. It also indicated that labeling with FITC did not affect the antigenicity. By using FITC-labeled FlaB as a tracer antigen, a homogeneous FPA was developed to detect antileptospiral antibodies in bovine sera. A population of 208 MAT-positive and 208 MAT-negative serum samples was tested by FPA. The FPA cutoff was determined by receiver operating characteristic analysis. By FPA, 83.7% of the MAT-positive serum samples were positive and 81.2% of the MAT-negative serum samples were negative. Compared to the results of MAT, the positive predictive value of FPA was 81.7% and the negative predictive value of FPA was 83.3%. The FPA is a simple and rapid technique for the detection of anti-
Leptospira
antibodies.
Modulation of T-Cell Responses to a Recall Antigen in Human T-Cell Leukemia Virus Type 1-Infected Individuals
Authors: Suzuki Muneou , Dezzutti Charlene S. , Okayama Akihiko , Tachibana Nobuyoshi , Tsubouchi Hirohito , Mueller Nancy , Lal Renu B. 
Published: December 2019

ABSTRACTTo determine the mechanism of the purified protein derivative (PPD)-specific hyporesponsiveness inMycobacterium bovisBCG-vaccinated human T-cell leukemia virus type 1 (HTLV-1)-infected individuals, we examined cytokine production in response to PPD in the following four groups of individuals: (i) HTLV-negative, PPD nonresponders (n= 11; NN); (ii) HTLV-negative, PPD responders (n= 18; NP); (iii) HTLV-positive, PPD nonresponders (n= 15; PN); and (iv) HTLV-positive, PPD responders (n= 15; PP). In vitro stimulation with PPD resulted in both proliferative responses and gamma interferon (IFN-γ) production in NP and PP (P< 0.02), with minimal proliferation and IFN-γ production in the NN and PN groups. Further, PPD-specific interleukin 10 (IL-10) production was significantly reduced in the PN group (P< 0.01), while the other groups had comparable levels. Cytokine reconstitution experiments demonstrated that while addition of recombinant IL-12 (rIL-12) plus anti-IL-4 restored PPD-specific responses in the NN group, it had no effect in the PN group. However, addition of rIL-12 resulted in the increased production of IFN-γ in both nonresponder groups (NN and PN), suggesting that the lack of IFN-γ production was not responsible for the PPD anergy. We conclude that PPD-specific anergy in HTLV-1-infected individuals appears to be due in part to their inability to respond to rIL-12.
A New Method with General Diagnostic Utility for the Calculation of Immunoglobulin G Avidity
Authors: Korhonen Maria H. , Brunstein John , Haario Heikki , Katnikov Alexei , Rescaldani Roberto , Hedman Klaus 
Published: December 2019

ABSTRACT

The reference method for immunoglobulin G (IgG) avidity determination includes reagent-consuming serum titration. Aiming at better IgG avidity diagnostics, we applied a logistic model for the reproduction of antibody titration curves. This method was tested with well-characterized serum panels for cytomegalovirus, Epstein-Barr virus, rubella virus, parvovirus B19, and
Toxoplasma gondii
. This approach for IgG avidity calculation is generally applicable and attains the diagnostic performance of the reference method while being less laborious and twice as cost-effective.
Variability of the Glycoprotein G Gene in Clinical Isolates of Herpes Simplex Virus Type 1
Authors: Rekabdar Elham , Tunbäck Petra , Liljeqvist Jan-Åke , Bergström Tomas 
Published: December 2019

ABSTRACT

Glycoprotein G (gG) of herpes simplex virus type 1 (HSV-1) has been used as a prototype antigen for HSV-1 type-specific serodiagnosis, but data on the sequence variability of the gene coding for this protein in wild-type strains are lacking. In this study, direct DNA sequencing of the gG-1 genes from PCR products was performed with clinical HSV-1 isolates from 11 subjects as well as with strains Syn 17
+
, F, and KOS 321. The reference strains Syn 17
+
and F showed a high degree of conservation, while KOS 321 carried 13 missense mutations and, in addition, 12 silent mutations. Three clinical isolates showed mutations leading to amino acid alterations: one had a mutation of K
122
to N, which is a gG-1–to–gG-2 alteration; another contained all mutations which were observed in KOS 321 except two silent mutations; and the third isolate carried five missense mutations. Two clinical isolates as well as strain KOS 321 showed a mutation (F
111
→V) within the epitope of a gG-1-reactive monoclonal antibody (MAb). When all viruses were tested for reactivity with the anti-gG-1 MAb, the three strains with the F
111
→V mutation were found to be unreactive. Furthermore, gG-1 antibodies purified from sera from the two patients carrying strains mutated in this epitope were less reactive when they were tested by an HSV-1-infected-cell assay. Therefore, our finding that the sequence variability of the gG-1 gene also affects B-cell epitope regions of this protein in clinical isolates may have consequences for the use of this protein as a type-specific antigen for serodiagnosis.
Antibiotics Modulate Vaccine-Induced Humoral Immune Response
Authors: Woo Patrick C. Y. , Tsoi Hoi-Wah , Wong Lei-Po , Leung Harry C. H. , Yuen Kwok-Yung 
Published: December 2019

ABSTRACTThe effects of antibiotics on the antigen-specific humoral immune response are not known. Macrolides, tetracyclines, and beta-lactams are commonly prescribed antibiotics. The first two are known to have immunomodulatory activities. The effects of clarithromycin, doxycycline, and ampicillin on the primary and secondary antibody responses to tetanus toxoid, a pneumococcal polysaccharide vaccine, a hepatitis B virus surface antigen (HBsAg) vaccine, and live attenuatedSalmonella typhi(Ty21a) were investigated using a mouse model. For the mice receiving the tetanus toxoid, the immunoglobulin M (IgM) level of the clarithromycin group at day 7 was significantly lower than the corresponding antibody level of the normal saline (NS) group. For the mice receiving the pneumococcal polysaccharide vaccine, the total antibody and IgM levels of the clarithromycin group and the IgM level of the doxycycline group at day 7 were significantly lower than the corresponding antibody levels of the ampicillin and NS groups. For the mice receiving the HBsAg vaccine, the IgM level of the doxycycline group at day 7 was significantly lower than the corresponding antibody levels of the clarithromycin and NS groups, while the IgM level of the clarithromycin group at day 28 was significantly lower than the corresponding antibody levels of the doxycycline, ampicillin, and NS groups. For the mice receiving all three vaccines, there were no statistically significant differences between any of the antibody levels of the ampicillin group and the corresponding antibody levels of the NS group. For the mice receiving Ty21a, the total antibody levels of the ampicillin group at days 7 and 21 were significantly higher than the corresponding antibody levels of the NS group. Moreover, the IgM levels of the clarithromycin, doxycycline, and ampicillin groups at days 7 and 21 were significantly higher than the corresponding antibody levels of the NS group. Furthermore, the total antibody level of the ampicillin group at day 21 was significantly higher than the corresponding antibody level of the doxycycline group. For all four vaccines, there were no statistically significant differences among the serum levels of interleukin-10 and gamma interferon for the mice treated with the various antibiotics. We conclude that clarithromycin and doxycycline, but not ampicillin, suppress the antibody responses of mice to T-cell-dependent and T-cell-independent antigens, whereas all three antibiotics enhance the antibody response to live attenuated mucosal bacterial vaccines.
Development of a Recombinant Antigen for Antibody-Based Diagnosis of
Mycoplasma bovis
Infection in Cattle
Authors: Brank Marion , Le Grand Dominique , Poumarat François , Bezille Pierre , Rosengarten Renate , Citti Christine 
Published: December 2019

ABSTRACT

Mycoplasma bovis
induces various clinical manifestations in cattle, such as mastitis, arthritis, and pneumonia. We have evaluated the immunoreactivity of three variable surface proteins (Vsps) of
M. bovis
, namely VspA, VspB, and VspC, with sera collected from herds with mycoplasmosis or from cattle experimentally infected with
M. bovis
. Western blot analysis revealed that the Vsps are the predominant antigens recognized by the host humoral response during
M. bovis
infection. The immunoreactivity of VspA, VspB, and VspC with host antibodies was independent of the clinical manifestations, the geographical origin of the
M. bovis
isolates, the mode of infection, and the animal’s history. Moreover, the results showed that Vsp-specific host antibodies can be detected about 10 days after experimental infection and for up to several months. The full-length or truncated versions of the VspA product were overexpressed in
Escherichia coli
as fusion proteins (FP-VspA). Recombinant products showed strong immunoreactivity with the Vsp-specific monoclonal antibodies 1A1 and 1E5, with the corresponding epitopes localized at the VspA N-terminal and C-terminal ends, respectively. Anti-
M. bovis
sera of cattle naturally or experimentally infected also strongly recognized the full-length FP-VspA. The seroreactivity of sera collected from cattle between 6 and 10 days after experimental infection was weaker with truncated versions of VspA lacking the 1E5 epitope than with the full-length VspA or the truncated versions lacking the 1A1 epitope. Overall, the results indicate that the Vsps, despite their inter- and intraclonal variability, may be applied as target antigens in serodiagnostic assays for epidemiological studies.
Decay of Passively Acquired Maternal Antibodies against Measles, Mumps, and Rubella Viruses
Authors: Nicoara Corina , Zäch Kristina , Trachsel Daniel , Germann Daniel , Matter Lukas 
Published: December 2019

ABSTRACT
The decay of maternally derived antibodies to measles, mumps, and rubella viruses in Swiss infants was studied in order to determine the optimal time for vaccination. A total of 500 serum or plasma samples from infants up to 2 years of age were tested by enzyme-linked immunosorbent assay and fluorescent-antibody testing. The decline of antibody prevalence was slowest against the measles virus. By 9 to 12 months of age, only 5 of 58 (8.6%; 95% CI, 2.9 to 19.0) infants were antibody positive for the measles virus, and only 2 had levels above 200 mIU/ml. Mumps and rubella virus antibody seropositivity was lowest at 9 to 12 months of age with 3 of 58 (5.2%; 95% CI, 1.1 to 14.4) infants and at 12 to 15 months with 1 of 48 (2.1%; 95% CI, 0.1 to 11.1) infants, respectively. Concentrations of passively acquired antibodies decreased rapidly within the first 6 months of life. We observed no significant differences in antibody prevalence or concentration according to gender in any age group. In conclusion, MMR vaccination at 12 instead of 15 months of age could reduce the pool of susceptible subjects in infancy and support the efforts to eliminate these infections, particularly in combination with a second vaccine dose before school entry.
Role of p38 in the Priming of Human Neutrophils by Peritoneal Dialysis Effluent
Authors: Daniels Ian , Fletcher John , Haynes Andrew Paul 
Published: December 2019

ABSTRACTPeritoneal dialysis effluent (PDE) contains a low-molecular-weight substance that is able to prime human neutrophils for the release of arachidonic acid and superoxide anion. Conventional priming agents, such as tumor necrosis factor alpha (TNF-α), are known to signal via mitogen-activated protein (MAP) kinases; at least one possible substrate for MAP kinases is cytosolic phospholipase A2(cPLA2). Phosphorylation of this enzyme results in arachidonic acid release, and this fatty acid is a potent primer and activator of the human neutrophil NADPH oxidase. Because of the striking similarities between the priming of neutrophils with agents such as TNF-α and PDE, we have investigated the signalling pathways evoked by PDE and explored the possibility that cPLA2is a target for activated MAP kinases. Our results show that PDE treatment of human neutrophils results in the phosphorylation of the p38 kinase rather than the p42 and p44 kinases. Phosphorylation of p38 is transient with maximal activity being observed 1 min after exposure to PDE. We were unable to demonstrate that activation of p38 resulted in phosphorylation of cPLA2; furthermore, translocation of this enzyme to a membrane-containing fraction was not enhanced in PDE-treated neutrophils. Taken together, these data suggest that, in a manner similar to that of TNF-α, PDE primes human neutrophils by the activation of the p38 kinase. However, unlike the cytokine, the activation of this protein does not result in phosphorylation or activation of cPLA2.
Can an Antibiotic (Macrolide) Prevent
Chlamydia pneumoniae
-Induced Atherosclerosis in a Rabbit Model?
Authors: Fong Ignatius W. , Chiu Brian , Viira Esther , Jang Dan , Fong Michael W. , Peeling Rosanna , Mahony James B. 
Published: December 2019

ABSTRACT

There is increasing data implicating
Chlamydia pneumoniae
in the pathogenesis of atherosclerosis, and antibiotics may theoretically be useful to prevent secondary vascular complications. Three groups of New Zealand White specific-pathogen-free rabbits, fed cholesterol-free chow, were inoculated via the nasopharynx on three occasions, 2 weeks apart, with
C. pneumoniae
. Group I (
n
= 23) rabbits were untreated; group II (
n
= 24) rabbits were treated with azithromycin at 30 mg/kg of body weight daily for 3 days and then once every 6 days, starting 5 days after first inoculation and continuing until sacrifice (early treatment); and group III (
n
= 24) rabbits were treated with the same dose of azithromycin but initiated 2 weeks after the last inoculation. All animals were sacrificed at 10 to 11 weeks after initial inoculation and examined for signs of atherosclerosis of the aorta. Eight (34.8%) untreated rabbits developed early signs of atherosclerosis, whereas only one (4.2%) in the early-treatment group had such signs (
P
= 0.02). However, eight rabbits (33.3%) of the delayed-treatment group had atherosclerotic changes of the aorta and no significant reduction compared to untreated rabbits. Early treatment of
C. pneumoniae
-infected rabbits with azithromycin was highly effective (87%) in preventing atherosclerotic changes, but delayed treatment was ineffective. It is possible that longer or more aggressive antibiotic treatment may be needed to reverse preformed lesions or that antibiotics may not be of value once lesions have formed.
Sézary T-Cell Activating Factor Is aChlamydia pneumoniae-Associated Protein
Authors: Abrams J. Todd , Vonderheid Eric C. , Kolbe Sonya , Appelt Denah M. , Arking E. James , Balin Brian J. 
Published: December 2019

ABSTRACTWe previously identified a protein that was stimulatory for malignant Sézary T cells, termed Sézary T-cell activating factor (SAF). However, the identity of this protein has not been fully elucidated, nor has it’s role been determined in the pathogenesis of cutaneous T-cell lymphoma (CTCL). The basis for epidermotropism and proliferation of malignant cells in the skin of patients with CTCL is unknown. Using a monoclonal antibody inhibitory for SAF activity, we demonstrated that SAF is present in the skin of 16 of 27 samples from patients with mycosis fungoides, the predominant form of CTCL. In this report, the SAF determinant is demonstrated to be associated withChlamydia pneumoniaebacteria by immunohistochemistry, immunoelectron microscopy, and culture analysis. Reactivity of antibodies against an outer membrane protein ofC. pneumoniaeor against the lipopolysaccharide ofChlamydiaespp. demonstrated that these determinants are coexpressed in 90% of the SAF-positive samples. We confirmed the presence ofC. pneumoniaeDNA and RNA in the skin by PCR and reverse transcription-PCR and by sequence analysis of the PCR products. The expression of theC. pneumoniaeantigens and SAF appears to be associated with active disease in thatC. pneumoniaeantigens were absent or greatly diminished in the skin of three patients examined after Psoralen and long-wave UVA radiation treatment. Our results suggest that SAF is aChlamydia-associated protein and that further investigation is warranted to determine whether SAF andC. pneumoniaeplay a role in the pathogenesis of CTCL.
Genotyping of the CCR5 Chemokine Receptor by Isothermal NASBA Amplification and Differential Probe Hybridization
Authors: Romano Joseph W. , Tetali Surya , Lee Eun Mi , Shurtliff Roxanne N. , Wang Xue Ping , Pahwa Savita , Kaplan Mark H. , Ginocchio Christine C. 
Published: December 2019

ABSTRACT
The human CCR5 chemokine receptor functions as a coreceptor with CD4 for infection by macrophage-tropic isolates of human immunodeficiency virus type 1 (HIV-1). A mutated CCR5 allele which encodes a protein that does not function as a coreceptor for HIV-1 has been identified. Thus, expression of the wild-type and/or mutation allele is relevant to determining the infectibility of patient peripheral blood mononuclear cells (PBMC) and affects disease progression in vivo. We developed a qualitative CCR5 genotyping assay using NASBA, an isothermal nucleic acid amplification technology. The method involves three enzymes and two oligonucleotides and targets the CCR5 mRNA, which is expressed in PBMC at a copy number higher than 2, the number of copies of DNA present encoding the gene. The single oligonucleotide set amplifies both alleles, and genotyping is achieved by separate hybridizations of wild-type- and mutation-specific probes directly to the single-stranded RNA amplification product. Assay sensitivity and specificity were demonstrated with RNAs produced in vitro from plasmid clones bearing the DNA encoding each allele. No detectable cross-reactivity between wild-type and mutation probes was found, and 50 copies of each allele were readily detectable. Analysis of patient samples found that 20% were heterozygous and 1% were homozygous for the CCR5 mutation. Thus, NASBA is a sensitive and specific means of rapidly determining CCR5 genotype and provides several technical advantages over alternative assay systems.
Relative Avidities of Human Immunoglobulin G Antibodies for Streptococcal Pyrogenic Exotoxins A and B
Authors: Mascini Ellen M. , Jansze Margriet , Verhoef Jan , van Dijk Hans 
Published: December 2019

ABSTRACT

In this pilot study, we investigated the relative avidities for streptococcal pyrogenic exotoxin A (SPE-A) and SPE-B of antibodies in sera from patients with fatal streptococcal toxic shock-like syndrome and from healthy individuals and in intravenous immunoglobulin (IVIG) preparations. We observed a great variation in the relative avidities of patient, control, and IVIG immunoglobulin G (IgG) (values estimated to be between 10
−7
and 10
−11
M), with mean values for patient IgG about 10-fold lower than those of control IgG.
Distinct Characteristics of Resistance toBorrelia burgdorferi-Induced Arthritis in C57BL/6N Mice
Authors: Ma Ying , Seiler Kathleen Petri , Eichwald Ernst J. , Weis John H. , Teuscher Cory , Weis Janis J. 
Published: December 2019

ABSTRACTStudies of mice infected withBorrelia burgdorferihave indicated that the severity of arthritis is influenced by the genetic composition of the host: the C3H mouse develops severe arthritis while BALB/c and C57BL/6 mice develop mild arthritis. In this study, the effects of increasing infectious dose on the severity of arthritis were determined in these three mouse strains. C3H/He mice developed severe arthritis at all infectious doses, with 100% infection requiring 200 spirochetes. In BALB/cAnN mice, arthritis severity was dependent on infectious dose; symptoms were mild with infection by 200B. burgdorferiand progressively more severe with increasing infectious dose. Infection of BALB/cAnN mice with 2 × 104B. burgdorferiresulted in arthritis with severity identical to that in C3H/He mice. Spirochete levels in rear ankle joints of C3H/HeJ and C3H/HeN mice were relatively high, as detected by PCR, and did not increase with infectious dose. Spirochete levels in joints from BALB/cAnN mice increased with increasing infectious dose to levels found in severely arthritic C3H/He mice. Thus, resistance to severe arthritis in BALB/cAnN mice was conditional: it could be overcome by high infectious dose and the arthritis became severe when high levels ofB. burgdorferiwere present in joints. A unique response to increasing infectious dose was seen in C57BL/6N mice, which displayed mild to moderate arthritis at all doses ofB. burgdorferitested, up to 2 × 105. At all infectious doses, the levels of spirochetes in ankle joints of C57BL/6N mice were high, equivalent to those found in the severely arthritic C3H/He mice. The arthritis observed in infected (C57BL/6N × C3H/HeN)F1mice was of severity intermediate between those of the two parental strains. The finding that resistance to severe arthritis in C57BL/6N mice could not be overcome by high infectious doses and was independent of spirochete levels in joints suggested that it was mediated by a distinct mechanism from that operating in BALB/cAnN mice.
Identification and Characterization of Protective T Cells in hsp65 DNA-Vaccinated andMycobacterium tuberculosis-Infected Mice
Authors: Bonato Vania L. D. , Lima Valeria M. F. , Tascon Ricardo E. , Lowrie Douglas B. , Silva Celio L. 
Published: December 2019

ABSTRACTImmunization by intramuscular injection of plasmid DNA expressing mycobacterial 65-kDa heat shock protein (hsp65) protects mice against challenge with virulentMycobacterium tuberculosisH37Rv. During infection or after immunization, CD4+/CD8−and CD8+/CD4−hsp65-reactive T cells increased equally in spleens. During infection, the majority of these cells were weakly CD44 positive (CD44lo) and produced interleukin 4 (IL-4) whereas after immunization the majority were highly CD44 positive (CD44hi) and produced gamma interferon (IFN-γ). In adoptive transfer of protection to naive mice, the total CD8+/CD4−cell population purified from spleens of immunized mice was more protective than that from infected mice. When the cells were separated into CD4+/CD8−and CD8+/CD4−types and then into CD44hiand CD44lotypes, CD44locells were essentially unable to transfer protection, the most protective CD44hicells were CD8+/CD4−, and those from immunized mice were much more protective than those from infected mice. Thus, whereas the CD44loIL-4-producing phenotype prevailed during infection, protection was associated with the CD8+/CD44hiIFN-γ-producing phenotype that predominated after immunization. This conclusion was confirmed and extended by analysis of 16 hsp65-reactive T-cell clones from infected mice and 16 from immunized mice; the most protective clones, in addition, displayed antigen-specific cytotoxicity.