bluuebunny/crossref_metadata_2025_split huggingface dataset:
Cholera Toxin Indirectly Activates Human Monocyte-Derived Dendritic Cells In Vitro through the Production of Soluble Factors, Including Prostaglandin E2and Nitric Oxide
Authors: Bagley Kenneth C. , Abdelwahab Sayed F. , Tuskan Robert G. , Lewis George K. 
Published: January 2006

ABSTRACTCholera toxin (CT) is a potent adjuvant that activates dendritic cells (DC) by increasing intracellular cyclic AMP (cAMP) levels. In vivo and in vitro, very small amounts of CT induce potent adjuvant effects and activate DC. We hypothesized that DC intoxicated by CT may release factors that enhance their own maturation and induce the maturation of toxin-free bystander DC. Through the use of mixed cultures and transwell cultures, we found that human monocyte-derived DC (MDDC) pulsed with CT or other cAMP-elevating agonists induce the maturation of bystander DC. Many DC agonists including CT increase the production of prostaglandin E2(PGE2) and nitric oxide (NO). For this reason, we determined whether the actions of PGE2or NO are involved in the maturation of MDDC induced by CT or dibutyryl-cAMP (d-cAMP). We found that blocking the production of PGE2or blocking prostaglandin receptors inhibited MDDC maturation induced by CT and d-cAMP. Likewise, sequestering NO or blocking the downstream actions of NO resulted in the inhibition of MDDC maturation induced by CT and d-cAMP. These results indicate that endogenously produced factors including PGE2and NO contribute to the maturation of DC induced by CT and that these factors participate in bystander DC maturation. The results of this study may help explain why bacterial toxins that elevate cAMP are such potent adjuvants.
Mycoplasma suisAntigens Recognized during Humoral Immune Response in Experimentally Infected Pigs
Authors: Hoelzle L. E. , Hoelzle K. , Ritzmann M. , Heinritzi K. , Wittenbrink M. M. 
Published: January 2006

ABSTRACTToday, serodiagnostic tests forMycoplasma suisinfections in pigs have low accuracies. The development of novel serodiagnostic strategies requires a detailed analysis of the humoral immune response elicited byM. suisand, in particular, the identification of antigenic proteins of the agent. For this study, indirect enzyme-linked immunosorbent assay (ELISA) and immunoblot analyses were performed using pre- and sequential postinoculation sera fromM. suis-infected and mock-infected control pigs.M. suispurified from porcine blood served as the antigen. EightM. suis-specific antigens (p33, p40, p45, p57, p61, p70, p73, and p83) were identified as targets of the immunoglobulin G (IgG) antibody response during experimental infection, with p40, p45, and p70 being the preferentially recognizedM. suisantigens. Besides theM. suis-specific antigens, porcine immunoglobulins were identified in blood-derivedM. suispreparations. By immunoglobulin depletion, the specificity of theM. suisantigen for use in indirect ELISA was significantly improved.M. suis-specific Western blot and ELISA reactions were observed in all infected pigs by 14 days postinfection at the latest and until week 14, the end of the experiments. During acute clinical attacks of eperythrozoonosis, a derailment of the antibody response, determined by decreases in both theM. suisnet ELISA values and the numbers ofM. suis-specific immunoblot bands, was accompanied by peaking levels of autoreactive IgG antibodies. In conclusion, theM. suis-specific antigens found to stimulate specific IgG antibodies are potentially useful for the development of novel serodiagnostic tests.
Longitudinal Analysis of
Cryptosporidium
Species-Specific Immunoglobulin G Antibody Responses in Peruvian Children
Authors: Priest Jeffrey W. , Bern Caryn , Xiao Lihua , Roberts Jacquelin M. , Kwon James P. , Lescano Andres G. , Checkley William , Cabrera Lilia , Moss Delynn M. , Arrowood Michael J. , Sterling Charles R. , Gilman Robert H. , Lammie Patrick J. 
Published: January 2006

ABSTRACT

Cryptosporidium
species are ubiquitous in the environment and are frequently detected in the stools of children who live where sanitation conditions are poor. To better characterize the immune response to these parasites, we monitored immunoglobulin G (IgG) antibody levels in a cohort of children from Lima, Peru. Two new enzyme-linked immunosorbent assays based on the
C. parvum
(bovine, subtype IIa) Iowa strain 17-kDa and 27-kDa antigens were used to measure IgG antibody levels in longitudinal serum samples. Antibody responses were detected during infections with
C. parvum
,
C. felis
, and
C. meleagridis
and with four different subtypes of
C. hominis
. We also noted that the magnitude of the antibody response was related to the number of previous infections and that older children generally had higher levels of antibodies to the two
C. parvum
antigens. Antibody responses were not associated with infections with either
Cyclospora
sp. or
Giardia
sp. We believe the antibody assays will be important tools for monitoring the success of future public health interventions.
Epithelial Toll-Like Receptor 5 Is Constitutively Localized in the Mouse Cecum and Exhibits Distinctive Down-Regulation during Experimental Colitis
Authors: Ortega-Cava Cesar F. , Ishihara Shunji , Rumi Mohammad A. K. , Aziz M. M. , Kazumori Hideaki , Yuki Takafumi , Mishima Yoshiyuki , Moriyama Ichiro , Kadota Chikara , Oshima Naoki , Amano Yuji , Kadowaki Yasunori , Ishimura Norihisa , Kinoshita Yoshikazu 
Published: January 2006

ABSTRACT
We recently demonstrated that the pattern recognition receptors (PRRs) toll-like receptor 2 (TLR2), TLR4, and CD14 are expressed in mouse colonic epithelium in a compartmentalized manner. Here we report the localization of TLR5, the receptor for bacterial flagellin, and its distinctive down-regulation during experimental colitis. Guts from normal BALB/c mice and those with dextran sodium sulfate (DSS)-induced colitis were compared. Each gut was divided into seven segments (stomach, small intestine [three parts], and colon [three parts]), and epithelial cells and crypt units were collected by scraping and EDTA treatment, respectively. Northern blotting showed that TLR5 mRNA was preferentially expressed in the epithelium of the proximal colon in normal mice. Laser capture microdissection coupled to reverse transcriptase PCR confirmed this localization. TLR5 protein expression reflected mRNA expression, as evidenced by Western blotting. In mice with acute colitis, inflammation occurred mainly in the distal colon. Interestingly, while TLR2, TLR4, and CD14 were up-regulated in the inflamed colon, TLR5 was down-regulated at both the mRNA and protein levels. Decreased TLR5 expression was more evident during chronic colitis. Additional in vitro studies using a mouse cell line, Colon-26, showed that gamma interferon (IFN-γ) time- and dose-dependently down-regulates TLR5. In conclusion, epithelial cells, mainly in the proximal colon, constitutively express TLR5. TLR5 expression is down-regulated in vivo during acute and chronic DSS-induced colitis, in contrast to the expression of TLR2, TLR4, and CD14. The mechanism governing TLR5 regulation may therefore differ from that controlling other PRRs. Finally, IFN-γ may be involved in down-regulating TLR5 expression.
Multilocus Sequence Types, Serotypes, and Variants of the Surface Antigen PspA in
Streptococcus pneumoniae
Isolates from Meningitis Patients in Poland
Authors: Sadowy Ewa , Skoczyñska Anna , Fiett Janusz , Gniadkowski Marek , Hryniewicz Waleria 
Published: January 2006

ABSTRACT

Meningitis caused by
Streptococcus pneumoniae
represents an important factor of morbidity and mortality in humans. In a significant number of cases, this disease is associated with specific clones of the organism, the so-called invasive pneumococcal clones. The aim of the study was to analyze 156
S. pneumoniae
isolates identified as etiological agents of meningitis in Poland in the years 1997 through 2002. The isolates were characterized by multilocus sequence typing (MLST), and the results were compared with those obtained by pulsed-field gel electrophoresis (PFGE) and with the MLST data on invasive pneumococci from other countries. Eighty-nine different sequence types were found in the group of isolates, 50 of which had been known before including 19 of the major invasive clones. However, a significant fraction of the isolates possessed novel combinations of known and new MLST alleles. The majority of penicillin-nonsusceptible isolates belonged to the group of international multiresistant clones (Spain
23F
-1, Spain
6B
-2, Spain
9V
-3, Poland
23F
-16, and Poland
6B
-20), which underlined the importance of these in the dissemination of antimicrobial resistance. The results of the MLST analysis correlated well with the PFGE data, thus again demonstrating good congruence between the two typing methods for
S. pneumoniae
. The majority of the isolates (95.5%) belonged to families 1 or 2 of the surface protein PspA, confirming its potential usefulness as the vaccine antigen candidate.
Reverse Line Blot Assay for Direct Identification of Seven
Streptococcus agalactiae
Major Surface Protein Antigen Genes
Authors: Zhao Zuotao , Kong Fanrong , Gilbert Gwendolyn L. 
Published: January 2006

ABSTRACT

We developed a multiplex PCR-based reverse line blot hybridization assay (mPCR/RLB) to detect the genes encoding members of the family of variable surface-localized proteins of
Streptococcus agalactiae
(group B streptococcus [GBS]), namely, Bca (Cα), Rib, Epsilon (Epsilon/Alp1/Alp5), Alp2, Alp3, and Alp4, and the immunoglobulin A binding protein, Bac (Cβ). We used the assay to identify these genes in a collection of well-characterized GBS isolates and reference strains. The results showed that mPCR/RLB avoids the common problems of cross-reaction and nontypability associated with protein typing using antisera. It is as sensitive as, but more practical than, separate gene-specific PCRs and would be suitable for large molecular epidemiological studies of GBS.
Evaluation of the INOVA Diagnostics Enzyme-Linked Immunosorbent Assay Kits for Measuring Serum Immunoglobulin G (IgG) and IgA to Deamidated Gliadin Peptides
Authors: Prince Harry E. 
Published: January 2006

ABSTRACT
New assays for antibodies to deamidated gliadin peptides (DGP) expressing celiac disease-specific epitopes were evaluated using 154 sera previously tested for endomysial immunoglobulin A (IgA) (EMA), transglutaminase IgA (TGA), and conventional gliadin antibodies. DGP antibody results showed 97% concordance with EMA and TGA results. Of 56 sera negative for EMA and TGA but positive for conventional gliadin antibodies, 54 (96%) were negative for DGP antibodies.
Human Endotoxemia Induces Down-Regulation of Monocyte CC Chemokine Receptor 2
Authors: Heesen Michael , Renckens Rosemarijn , de Vos Alex F. , Kunz Dagmar , van der Poll Tom 
Published: January 2006

ABSTRACTUpon injection ofEscherichia colilipopolysaccharide into human volunteers, the monocyte density of CC chemokine receptor 2 (CCR2) decreased. Minimal CCR2 density was observed 4 h after injection. Peak plasma concentrations of the CCR2 ligand monocyte chemotactic protein 1 and of tumor necrosis factor alpha were reached after 4 h and 2 h, respectively.
Neutralizing and Hemagglutination-Inhibiting Activities of Antibodies Elicited by the 2004-2005 Influenza Vaccine against Drifted Viruses
Authors: Ansaldi Filippo , Bacilieri Sabrina , Banfi Federica , Durando Paolo , Sticchi Laura , Icardi Giancarlo , Gasparini Roberto 
Published: January 2006

ABSTRACT
Evaluation of the antibody responses induced by the 2004-2005 influenza vaccine strain against the homologous variant, the 2004-2005 field isolates, and a previous circulating strain showed that a correlation between neutralizing and hemagglutination-inhibiting activities exists only when the antigen is very close to the vaccine strain.
Interleukin-6 Promotes Anti-OspA Borreliacidal Antibody Production In Vitro
Authors: Munson Erik L. , Nardelli Dean T. , Luk K. H. Kevin , Remington Monica C. , Callister Steven M. , Schell Ronald F. 
Published: January 2006

ABSTRACT
Determination of the immunological mediators responsible for promoting the production of borreliacidal antibody may facilitate the development of an improved borreliosis vaccine for human and veterinary use. Previously, we developed an in vitro assay to determine if borreliacidal antibody production could be augmented by treatment with different cytokines. In this study, in vitro treatment of lymph node cells producing borreliacidal antibody with recombinant interleukin-6 (rIL-6) resulted in a fourfold enhancement of anti-OspA borreliacidal antibody. Moreover, rIL-6 enhanced Western immunoblot titers and increased the number of B lymphocytes. In contrast, treatment of anti-OspA borreliacidal antibody-producing cells with anti-IL-6 resulted in a fourfold reduction in borreliacidal activity. Treatment with anti-IL-6 also inhibited enhanced borreliacidal antibody production induced by anti-gamma interferon. These data suggest that IL-6 plays a significant role in the production of anti-OspA borreliacidal antibodies.
Cellular Immune Responses in Asymptomatic Human Immunodeficiency Virus Type 1 (HIV-1) Infection and Effects of Vaccination with Recombinant Envelope Glycoprotein ofHIV-1
Authors: Gorse Geoffrey J. , Simionescu Ramona E. , Patel Gira B. 
Published: January 2006

ABSTRACTEffects of human immunodeficiency virus type 1 (HIV-1) recombinant envelope glycoprotein vaccines on cell-mediated immune (CMI) responses were assessed in HIV-1-infected patients. Asymptomatic, antiretroviral-treatment-naïve, HIV-1-infected patients with CD4+T-cell counts greater than 400/μl received multiple intramuscular injections of HIV-1 IIIB recombinant envelope glycoprotein (rgp160) vaccine or HIV-1 MN recombinant envelope glycoprotein (rgp120) vaccine (eight patients, referred to as the HIV-1 vaccinees) or placebo or hepatitis B vaccine (three patients, referred to as the controls). Lymphocyte proliferation in response to HIV-1 envelope glycoproteins, both homologous and heterologous to the HIV-1 immunogens, was absent prior to study treatment in all patients but increased significantly during the vaccination series and after the final vaccination in HIV-1 vaccinees (P< 0.05) and remained absent in control patients. In flow cytometric analyses of intracellular cytokines, T-cell receptor stimulation with an anti-CD3 antibody induced gamma interferon (IFN-γ) expression by activated CD4+and CD8+lymphocytes at greater frequencies than did stimulation with recombinant envelope glycoprotein and p24 of HIV-1 (P< 0.05). Mean frequencies of HIV-1 envelope glycoprotein-stimulated, activated intracellularIFN-γ-producing CD4+and CD8+lymphocytes and of interleukin-2-producing CD4+lymphocytes did not increase after vaccination, but cytokine-producing cells were detectable in some patients. Comparing pre- to post-HIV-1 vaccination time points, changes in frequencies of activated, IFN-γ-producing CD4+cells correlated inversely with changes in lymphocyte proliferation in response to recombinant envelope glycoprotein in HIV-1 vaccinees (P< 0.05). Increased CMI responses to HIV-1 envelope glycoprotein measured by lymphocyte proliferation were associated with HIV-1 recombinant envelope glycoprotein vaccines.
Immunoglobulin G Avidity in Differentiation between Early and Late Antibody Responses to West Nile Virus
Authors: Fox Janet L. , Hazell Stuart L. , Tobler Leslie H. , Busch Michael P. 
Published: January 2006

ABSTRACT
In 1999 West Nile virus (WNV) surfaced in the United States in the city of New York and spread over successive summers to most of the continental United States, Canada, and Mexico. Because WNV immunoglobulin M (IgM) antibodies have been shown to persist for up to 1 year, residents in areas of endemicity can have persistent WNV IgM antibodies that are unrelated to a current illness with which they present. We present data on the use of IgG avidity testing for the resolution of conflicting data arising from the testing of serum or plasma for antibodies to WNV. Thirteen seroconversion panels, each consisting of a minimum of four samples, were used. All samples were tested for the presence of WNV IgM and IgG antibodies, and the avidity index for the WNV IgG-positive samples was calculated. Panels that exhibited a rise in the WNV IgM level followed by a sequential rise in the WNV IgG level were designated “primary.” Panels that exhibited a marked rise in the WNV IgG level followed by a sequential weak WNV IgM response and that had serological evidence of a prior flavivirus infection were designated “secondary.” All samples from the “primary” panels exhibited low avidity indices (less than 40%) for the first 20 to 30 days after the recovery of the index sample (the sample found to be virus positive). All of the “secondary” samples had elevated WNV IgG levels with avidity indices of ≥55%, regardless of the number of days since the recovery of the index sample. These data demonstrate that it is possible to differentiate between recent and past exposure to WNV or another flavivirus through the measurement of WNV IgG avidity indices.
Simultaneous Detection of Antibodies to Six Nonhuman-Primate Viruses by Multiplex Microbead Immunoassay
Authors: Khan Imran H. , Mendoza Sara , Yee JoAnn , Deane Matthew , Venkateswaran Kodumudi , Zhou Shan S. , Barry Peter A. , Lerche Nicholas W. , Luciw Paul A. 
Published: January 2006

ABSTRACT
To maintain healthy nonhuman primates for use in biomedical research, animals are routinely screened for several infectious agents at most facilities. Commonly, monkey serum samples are tested by conventional immunoassays, such as enzyme-linked immunosorbent assays (ELISAs) or Western blotting, for antibodies to specific infectious agents. For testing for antibodies against multiple agents in each sample, conventional immunoassays are laborious and time-consuming. More efficient immunoassays are needed. Accordingly, we have developed a novel multiplex serodiagnostic system based on individually identifiable, fluorescent microbead sets, where each bead set is coated with antigens from a purified preparation of a specific virus. The coated bead sets are mixed to enable the detection of antibodies to multiple viruses in one serum or plasma sample. These viruses include four agents that are routinely tested for maintenance of specific-pathogen-free monkeys, namely, simian immunodeficiency virus, simian type D retrovirus, simian T-cell lymphotropic virus, and herpes B virus, as well as simian foamy virus and rhesus cytomegalovirus, both of which are commonly found in nonhuman primates. This multiplex microbead immunoassay (MMIA) enabled the simultaneous detection of antibodies to all six viruses in single serum samples as small as 1 microliter. The results obtained by MMIA analysis correlated with results of conventional ELISAs, which detect antibodies to single agents. Thus, this multiplex microbead detection system is an efficient diagnostic modality for serosurveillance of nonhuman primates.
Comparison of a New ESAT-6/CFP-10 Peptide-Based Gamma Interferon Assay and a Tuberculin Skin Test for Tuberculosis Screening in a Moderate-Risk Population
Authors: Porsa Emaeil , Cheng Lee , Seale Michael M. , Delclos George L. , Ma Xin , Reich Robert , Musser James M. , Graviss Edward A. 
Published: January 2006

ABSTRACT

Screening for latent tuberculosis infection (LTBI) with Mantoux tuberculin skin test (TST) has many limitations, including false-positive results due to exposure to
Mycobacterium
other than tuberculosis (TB) and BCG vaccination. A total of 474 adult inmates in a county jail were screened for LTBI using TST and a new ESAT-6/CFP-10 peptide-based whole-blood gamma interferon (IFN-γ) assay. LTBI prevalence was 9.0 and 5.4% as determined by TST and IFN-γ assay, respectively. Overall, agreement between test results was 90% (
κ =
0.25). Positive TST results were significantly associated with increased age (odds ratio [OR], 1.04; 95% confidence interval [CI], 1.01 to 1.08), African-American ethnicity (OR, 4.97; 95% CI, 1.58 to 15.68), foreign birth (OR, 20.20; 95% CI, 4.21 to 97.02) and prior incarceration (OR, 6.19; 95% CI, 1.48 to 25.95). Positive IFN-γ assay results were significantly associated with African-American ethnicity (OR, 5.58; 95% CI, 1.16 to 26.74). Factors associated with statistically significant discordance between TST and IFN-γ assay results were African-American ethnicity (OR, 0.29; 95% CI, 0.11 to 0.77), foreign birth (OR, 0.23; 95% CI, 0.07-0.80), and prior incarceration (OR, 0.06; 95% CI, 0.01-0.50). Among subjects born in the United States, African-American ethnicity was the only variable significantly associated with positive test results for both TST (OR, 4.26; 95% CI, 1.38 to 13.16) and IFN-γ assay (OR, 5.74; 95% CI, 1.19 to 27.75) and remained associated with statistically significant discordance between TST and IFN-γ assay results. The reactivity of the new IFN-γ assay is unaffected by prior BCG vaccination or serial TSTs but may be diminished in African-Americans. Future longitudinal studies are needed to assess the sensitivity and specificity of this new assay in detecting LTBI.
Recombinant Multiepitope Protein for Early Detection of Dengue Infections
Authors: AnandaRao Ravulapalli , Swaminathan Sathyamangalam , Fernando Sirimali , Jana Asha M. , Khanna Navin 
Published: January 2006

ABSTRACT

Dengue fever is a mosquito-borne viral disease prevalent mainly in tropical countries. As the clinical manifestations of dengue are not very unique, laboratory diagnosis is crucial in identifying cases of dengue infection. Detection of dengue infection based on the identification of antidengue antibodies has emerged as a practical and reliable means of diagnosing dengue fever. We recently developed a customized recombinant dengue multiepitope protein (r-DME-G) that can specifically detect the immunoglobulin G (IgG) class of antidengue antibodies in patient sera. Using this strategy, we have now created another dengue multiepitope protein, r-DME-M, with specificity for the IgM class of antidengue antibodies. A synthetic gene encoding the r-DME-M protein was expressed as a maltose-binding protein fusion in
Escherichia coli
. The recombinant protein was purified in a single affinity chromatographic step to obtain yields of ∼15 mg purified protein/liter of culture. The purified protein was used to develop an in-house IgM enzyme-linked immunosorbent assay (ELISA) and tested using a panel of 172 patient sera characterized using the commercially available Dengue Duo rapid strip test from PanBio, Australia. The IgM ELISA results showed that the r-DME-M protein not only recognized all IgM
+
samples identified by the PanBio test but also identified samples missed by the latter test. We also successfully adapted the r-DME-M protein to a rapid strip test format. This approach of creating customized antigens coupled to overexpression in
E. coli
and simple purification offers a promising alternative option to dengue diagnosis with the potential to circumvent the drawbacks of the whole virus antigen-based commercial kits.