bluuebunny/crossref_metadata_2025_split huggingface dataset:
Heat Shock Protein 70 of the Agent of Human Granulocytic Ehrlichiosis Binds toBorrelia burgdorferiAntibodies
Authors: Ijdo Jacob W. , Zhang Yan , Anderson Matthew L. , Goldberg David , Fikrig Erol 
Published: December 2019

ABSTRACTWe describe a patient with human granulocytic ehrlichiosis (HGE), a diagnosis confirmed by PCR and immunoblot analysis. Unexpectedly, immunoglobulin G (IgG) directed towards an 80-kDa ehrlichial antigen (without detectable IgM) was present in the patient’s serum in the first week of illness. Lyme disease immunoblots were reactive for IgG (but not IgM), a result indicative of prior exposure to the Lyme disease spirochete. Amino-terminal sequencing revealed that the 80-kDa ehrlichial antigen was an HSP-70 homolog similar toBorrelia burgdorferiHSP-70. We conclude that antibodies againstB. burgdorferiHSP-70 may cross-react with the ehrlichial heat shock protein and that this possibility must be considered when serologic test results for HGE and Lyme disease are interpreted.
Depressed Phagocytosis and Oxidative Burst in Polymorphonuclear Leukocytes from Individuals with Pulmonary Tuberculosis with or without Human Immunodeficiency Virus Type 1 Infection
Authors: Shalekoff Sharon , Tiemessen Caroline T. , Gray Clive M. , Martin Desmond J. 
Published: December 2019

ABSTRACT

Phagocytosis and oxidative burst in whole-blood granulocytes were assessed by flow cytometry with Phagotest and Bursttest kits, respectively. Seventy individuals were included in this study: 15 healthy, normal donors, 18 human immunodeficiency virus (HIV) type 1 (HIV-1)-seropositive patients, 19 patients with pulmonary tuberculosis (TB), and 18 patients co-infected with
Mycobacterium tuberculosis
and HIV-1 (TB-HIV). Granulocyte phagocytosis was assessed by incubating whole blood with fluorescence-labelled
Escherichia coli
and measuring the proportion of granulocytes with ingested bacteria and the capacity (fluorescence intensity) of each cell to phagocytose
E. coli
. The percentage of granulocytes converting nonfluorescent dihydrorhodamine to fluorescent rhodamine 123 on production of reactive oxygen intermediates (ROIs) and the mean channel shift were assessed as a measure of oxidative burst. No differences in the proportion of granulocytes that were capable of phagocytosing or producing ROIs in response to
E. coli
were observed between any of the study groups. Phagocytosis was significantly enhanced in granulocytes from HIV-1-infected individuals. On the other hand, granulocytes from individuals infected with
M. tuberculosis
alone or in combination with HIV-1 had a significantly reduced capacity to phagocytose
E. coli
and to produce ROIs in response to
E. coli
as an agonist. These results provide evidence that granulocytes from individuals with pulmonary TB with or without concomitant infection with HIV-1 have an impaired ability to phagocytose and to undergo oxidative burst, possibly contributing to the enhanced susceptibility to opportunistic infections in these patients.
Expression, Structure, and Location of Epitopes of the Major Surface Glycoprotein ofPneumocystis cariniif. sp.carinii
Authors: Linke Michael J. , Sunkin Susan M. , Andrews Ryan P. , Stringer James R. , Walzer Peter D. 
Published: December 2019

ABSTRACTThe major surface glycoprotein (MSG) ofPneumocystis cariniif. sp.cariniiconsists of a heterogeneous family of proteins that are encoded by approximately 100 unique genes. A genomic expression library was screened with a panel of MSG-specific monoclonal antibodies (MAbs) to identify conserved and rare epitopes. All of the antibodies reacted with epitopes that are encoded within the 5′ end of MSG. The results from the expression screening identified antibodies that recognize highly conserved, moderately conserved, and rare epitopes. Four MAbs (MAbs RA-F1, RA-E7, RA-G10, and RB-E3) reacted with a maltose binding protein–MSG-B fusion protein (MBPMSG-B41–1065) by immunoblotting and enzyme-linked immunosorbent assay. Three of the MAbs (MAbs RA-F1, RA-G10, and RA-E7) reacted with the same continuous epitope that was localized to amino acids 278 to 290 of MSG-B. Comparison of the sequence of the RA-F1-, RA-G10-, and RA-E7-reactive epitope to the deduced amino acid sequences of multiple MSGs demonstrated that it is highly conserved. The reactivity of RB-E3 with MSG-B was shown to be dependent on amino acids 184 to 192, which may comprise a portion of a discontinuous epitope.
HEp-2 Cell-Adherent
Escherichia coli
and Intestinal Secretory Immune Response to Human Immunodeficiency Virus (HIV) in Outpatients with HIV-Associated Diarrhea
Authors: Mathewson John J. , Salameh Bassam M. , DuPont Herbert L. , Jiang Zhi D. , Nelson Andrew C. , Arduino Roberto , Smith Melinda A. , Masozera Nicholas 
Published: December 2019

ABSTRACT

HEp-2 cell-adherent
Escherichia coli
and the human immunodeficiency virus (HIV) itself have recently been incriminated as causes of chronic HIV-associated diarrhea. This study sought to determine the prevalence of these two agents among HIV-infected patients with diarrhea in an outpatient setting in the United States and to compare their prevalence to that of other commonly recognized enteropathogens known to be present in this population. HEp-2 cell-adherent
E. coli
was found in 20 of 83 (24.1%) patients with diarrhea. A diffuse pattern of adherence was the most common, found in 14 of 20 (70%) patients, followed by a localized adherence pattern (6 of 20; 30%). An intestinal secretory immune response against the p24 antigen of HIV was found in 9 of 34 (27.5%) patients with HIV-associated diarrhea. The following pathogens or products were also detected in lower frequencies:
Cryptosporidium
spp. (10.8%),
Clostridium difficile
toxin (8.8%), microsporidia (6%),
Isospora belli
(3.6%),
Blastocystis hominis
(2.4%),
Giardia
spp. (1.2%),
Salmonella
spp. (1.2%), and
Mycobacterium
spp. (1.2%). The role of HEp-2 cell-adherent
E. coli
and HIV enteric infections in patients with HIV-associated diarrhea deserves further study.
Immunoreactivity of Five Monoclonal Antibodies against the 37-Kilodalton Common Cell Wall Protein (PsaA) ofStreptococcus pneumoniae
Authors: Crook Jennifer , Tharpe Jean A. , Johnson Scott E. , Williams Derrick B. , Stinson Annie R. , Facklam Richard R. , Ades Edwin W. , Carlone George M. , Sampson Jacquelyn S. 
Published: December 2019

ABSTRACTFive monoclonal antibodies (MAbs) were produced against theStreptococcus pneumoniaepneumococcal surface adhesin A (PsaA) 37-kDa common cell wall protein. These antibodies were used in a dot immunoblot and Western blot study of clinical isolates ofS. pneumoniaeto detect the presence of the protein. By both assays, the MAbs reacted with clinical isolates representing the 23 type-specific serotypes present in the licensed pneumococcal polysaccharide vaccine. Western blot analysis confirmed the presence of a protein migrating in the gel with a molecular mass of 37 kDa. An extension of the study by using dot immunoblot analysis that included an analysis of the 90 serotypes ofS. pneumoniaeshowed that all five MAbs reacted with 89 of the 90 serotypes tested. MAb 1B6, the exception, did not react withS. pneumoniaeserotype 16F. Dot immunoblot analysis of the MAbs withEnterococcus faecalisand viridans streptococci showed varied reactivity patterns, depending on the species. The MAbs against the 37-kDa antigen did not react withEscherichia coli, respiratory pathogens, or nonpathogens representing 22 genera and 29 species of bacteria. All five MAbs also reacted with five multidrug-resistant strains ofS. pneumoniae. In summary, these MAbs may be useful for detection of pneumococcal antigen and may lead to the development of diagnostic assays for pneumococcal disease.
Lipopolysaccharide from Nonvirulent Ara
+
Burkholderia pseudomallei
Isolates Is Immunologically Indistinguishable from Lipopolysaccharide from Virulent Ara
−
Clinical Isolates
Authors: Anuntagool Narisara , Intachote Pakamas , Wuthiekanun Vanaporn , White Nicholas J. , Sirisinha Stitaya 
Published: December 2019

ABSTRACT

Different lines of evidence suggest that a discrepancy between the distribution of
Burkholderia (Pseudomonas) pseudomallei
in the environment and the distribution of the disease melioidosis is attributable, at least in part, to phenotypic differences between clinical and some environmental isolates. Two antigenically and biochemically distinct biotypes have been described, only one of which is virulent. In this study, lipopolysaccharides (LPSs) were extracted by the proteinase K digestion method from a total of 214
B. pseudomallei
isolates, and their immunoreactivities with sera from patients with different clinical spectra and with other infections were evaluated. With the exception of 4 isolates from a total of 214 tested, the sodium dodecyl sulfate-polyacrylamide gel electrophoresis silver-staining profiles of the LPSs from the two biotypes showed identical ladder patterns that were typical for smooth LPSs from other gram-negative bacteria. The 210 isolates with typical LPS patterns (119 Ara
−
clinical, 13 Ara
−
soil, 70 Ara
+
soil, and 8 reference National Type Culture Collection strains) also exhibited similar immunoblot profiles against pooled sera from patients with melioidosis and hyperimmune mouse sera. Concordant findings were noted in the indirect enzyme-linked immunosorbent assay with Ara
−
and Ara
+
LPSs to coat the microtiter plates. The LPSs of the different
B. pseudomallei
biotypes appear antigenically indistinguishable. It is, therefore, unlikely that this component is related to the virulence and pathogenicity of
B. pseudomallei.
Development of a Blocking Enzyme-Linked Immunosorbent Assay for Detection of Serum Antibodies to O157 Antigen ofEscherichia coli
Authors: Laegreid William , Hoffman Mark , Keen James , Elder Robert , Kwang Jimmy 
Published: December 2019

ABSTRACTThe O157 antigen ofEscherichia colishares structural elements with lipopolysaccharide (LPS) antigens of other bacterial species, notablyBrucella abortusandYersinia enterocoliticaO9, a fact that confounds the interpretation of assays for anti-O157 antibodies. To address this problem, a blocking enzyme-linked immunosorbent assay (bELISA) was designed withE. coliO157:H7 LPS as the antigen and a monoclonal antibody specific forE. coliO157, designated 13B3, as the competing antibody. The bELISA had equivalent sensitivity to, and significantly higher specificity than, the indirect ELISA (iELISA), detecting anti-O157 antibodies in sera from cattle experimentally inoculated with O157:H7. Only 13% of sera from naive heifers vaccinated for or experimentally infected withB. abortushad increased anti-O157 bELISA titers, while 61% of anti-O157 iELISA titers were increased. The bELISA is a sensitive and specific method for the detection of serum antibodies resulting from exposure toE. coliO157.
Kinetics of Local and Systemic Immune Responses to an Oral Cholera Vaccine Given Alone or Together with Acetylcysteine
Authors: Kilhamn J. , Jertborn M. , Svennerholm A.-M. 
Published: December 2019

ABSTRACT
The possibility that a mucolytic drug, i.e., acetylcysteine, given orally may enhance the gut mucosal or systemic immune response to an oral B-subunit–whole-cell (B-WC) cholera vaccine was evaluated for 40 adult Swedish volunteers, and the kinetics of the immune responses were monitored for responding volunteers. Two doses of vaccine induced similar frequencies of immunoglobulin A (IgA) and IgG antitoxin responses (80 to 90%) and vibriocidal titer increases (60 to 65%) in serum irrespective of whether the vaccine was given alone or together with 2 g of acetylcysteine. In feces the frequencies of IgA antitoxin (67%) and antibacterial (33 to 40%) antibody responses were also comparable in the two immunization groups. Six months after vaccination, IgA and IgG antitoxin as well as vibriocidal antibody titer increases in serum could still be detected in approximately 80% of initially responding vaccinees. Significantly elevated fecal antitoxin and antibacterial IgA antibody levels were found in, respectively, 50 and 43% of those volunteers who initially had responded to the vaccine. Determination of IgA antibodies in feces does not seem to offer any advantages compared to determination in serum for assessment of immune responses after immunization with inactivated cholera vaccine.
Use of
trans
-Sialidase Inhibition Assay in a Population Serologically Negative for
Trypanosoma cruzi
but at a High Risk of Infection
Authors: Leguizamón María S. , Russomando Graciela , Rojas de Arias Antonieta , Samudio Margarita , Cabral Margarita , González-Cappa Stella Maris , Frasch Alberto Carlos C. , Campetella Oscar 
Published: December 2019

ABSTRACT

trans
-Sialidase inhibition assay (TIA) was employed in a population at high risk of
Trypanosoma cruzi
infection. From 20 serum samples that were negative by conventional serologic and parasitologic assays, 18 (90%) were reactive in TIA, providing further evidence of the higher sensitivity of TIA and suggesting that the actual prevalence of
T. cruzi
infection might be underestimated.
Serological, Hematologic, and PCR Studies of Cattle in an Area of Switzerland in Which Tick-Borne Fever (Caused by
Ehrlichia phagocytophila
) Is Endemic
Authors: Pusterla Nicola , Pusterla Jeannine Berger , Braun Ueli , Lutz Hans 
Published: December 2019

ABSTRACT

The purpose of this study was to examine the seasonal variations in seroprevalence to
Ehrlichia phagocytophila
in cattle pastured during the summer months in an area where tick-borne fever is endemic. The study was performed during a 1-year period from April 1996 to March 1997 and involved 34 cows, 22 pregnant heifers, and 14 calves. Blood samples, collected from all 70 cattle once a month, were used to determine serum immunoglobulin G titers by indirect immunofluorescence. In addition, blood smears were examined for
Ehrlichia
organisms, and PCR amplification was performed for the molecular detection of
E. phagocytophila
. Prior to the pasture period, the seroprevalence was 16%. Two weeks after the start of pasturing, it was 43%, after which it progressively increased and reached a maximum of 63% in September. The seroprevalence progressively decreased after the end of pasturing to a low of 23%. The variation in antibody titers was similar to that of seroprevalence.
E. phagocytophila
organisms were detected in blood smears of 7 animals and by nested PCR in 12. Only four cows, which were on the pastures of endemicity for the first time, had clinical signs of ehrlichiosis. This study demonstrated marked seasonal variations in seroprevalence and in serum titers of antibody to
E. phagocytophila
in cattle. The incidence of clinical signs of ehrlichiosis was increased in cattle grazing on the pastures of endemicity for the first time.
Cytokine Gene Expression in Normal Human Lymphocytes in Response to Stimulation
Authors: Fan Jiang , Nishanian Parunag , Breen Elizabeth C. , McDonald Matthew , Fahey John L. 
Published: December 2019

ABSTRACTSequential gene expression of two type 1 cytokines (interleukin 2 [IL-2] and gamma interferon), one type 2 cytokine (IL-10), two monokines (IL-6 and tumor necrosis factor alpha), and one cytokine receptor (IL-2 receptor [IL-2R]) in normal human peripheral blood mononuclear cells (PBMC) following in vitro stimulation was investigated by reverse transcription-PCR methods. Two stimuli were utilized: phytohemagglutinin (PHA), which acts on the CD2 molecule and T-cell receptors, and anti-CD3 monoclonal antibody, which acts on the CD3 molecule and on T-cell receptors. Increased expression of all studied genes occurred between 1 and 4 hours after stimulation, except for that of the gene encoding IL-10, which was delayed. Expression of all but one of the genes was transient, with a maximal mRNA accumulation at about 8 h on average. IL-2R mRNA expression was an exception, showing a prolonged increase (72 h). The general profiles of expression of the five cytokine genes were similar but not identical, suggesting some shared regulatory mechanisms. When responses to four additional stimuli (pokeweed mitogen,Candida albicans, and IL-2 at high and low doses) were compared, similar profiles of cytokine gene expression were found. Thus, the various stimuli caused induction of all cytokines with quantitative, not qualitative, differences. Altogether, the present data are useful for defining the kinetics of gene expression for key cytokines in response to standard immune-cell stimuli.
Correlation between Serological and Sequencing Analyses of the PorB Outer Membrane Protein in the
Neisseria meningitidis
Serotyping System
Authors: Sacchi Claudio T. , Lemos Ana P. S. , Whitney Anne M. , Solari Claude A. , Brandt Mary E. , Melles Carmo E. A. , Frasch Carl E. , Mayer Leonard W. 
Published: December 2019

ABSTRACT

The current serological typing scheme for
Neisseria meningitidis
is not comprehensive; a proportion of isolates are not serotypeable. DNA sequence analysis and predicted amino acid sequences were used to characterize the structures of variable-region (VR) epitopes on
N. meningitidis
PorB proteins (PorB VR typing). Twenty-six
porB
gene sequences were obtained from GenBank and aligned with 41 new sequences. Primary amino acid structures predicted from those genes were grouped into 30 VR families of related variants that displayed at least 60% similarity. We correlated VR families with monoclonal antibody (MAb) reactivities, establishing a relationship between VR families and epitope locations for 15 serotype-defining MAbs. The current panel of serotype-defining MAbs underestimates by at least 50% the PorB VR variability because reagents for several major VR families are lacking or because a number of VR variants within some families are not recognized by serotype-defining MAbs. These difficulties, also reported for serosubtyping based on the PorA protein, are shown as inconsistent results between serological and sequence analyses, leading to inaccurate strain identification and incomplete epidemiological data. The information from this study enabled the expansion of the panel of MAbs currently available for serotyping, by including MAbs of previously undetermined specificities. Use of the expanded serotype panel enabled us to improve the sensitivity of serotyping by resolving a number of formerly nonserotypeable strains. In most cases, this information can be used to predict the VR family placement of unknown PorB proteins without sequencing the entire
porB
gene. PorB VR typing complements serotyping, and a combination of both techniques may be used for full characterization of meningococcal strains. The present work represents the most complete and integrated data set of PorB VR sequences and MAb reactivities of serogroup B and C meningococci produced to date.
Multicolor Cytoenzymatic Evaluation of Dipeptidyl Peptidase IV (CD26) Function in Normal and Neoplastic Human T-Lymphocyte Populations
Authors: Ruiz Phillip , Zacharievich Natalia , Shenkin Mark 
Published: December 2019

ABSTRACTDipeptidyl peptidase IV (DPP IV), also identified as the glycoprotein CD26, is a transmembrane 110- to 120-kDa serine aminopeptidase involved in immune responses by influencing T-cell costimulation and by cleaving cytokines. Additionally, CD26 is a nonintegrin receptor that contains a binding site for extracellular matrix and other molecules. In order to further define the expression and functional activity of this membrane exopeptidase in human T cells, we developed a nondisruptive, four-color cytofluorogenic assay that utilizes three separate antibodies to cell-surface molecules (e.g., CD4/CD8/CD26 and CD19/CD56/CD26) along with a rhodamine 110-conjugated dipeptide substrate that allows the measurement of DPP IV activity in phenotypically defined cells. We found normal human thymi to have notable differences in time-dependent DPP IV activity among the thymocyte subsets defined by their CD4/CD8 phenotype, with CD4−/CD8−thymocytes containing less DPP IV activity than cells expressing CD4 and/or CD8 (i.e., maturing). CD26 positivity was moderately intense in thymocytes and tended to identify cells with higher DPP IV activity. The four-color technique was also used to examine mature peripheral blood lymphocytes, along with an assortment of leukemias and transformed T-cell lines. These experiments revealed that while DPP IV was consistently evident in normal T cells, neoplastic T cells could vary in their expression patterns. Furthermore, the presence (or intensity) of surface CD26 in some abnormal T cells and certain normal peripheral blood mononuclear cells was separable from the level of DPP IV measured intracellularly. Our results established that multicolor cytofluorographic analysis can be a practical means to measure DPP IV activity in various human cell populations. Furthermore, we found that DPP IV activity could vary in T cells according to their differentiation status and that under certain circumstances surface CD26 expression can be disassociated from the level of measured enzyme (i.e., DPP IV) activity.
A Bereavement Support Group Intervention Is Longitudinally Associated with Salutary Effects on the CD4 Cell Count and Number of Physician Visits
Authors: Goodkin Karl , Feaster Daniel J. , Asthana Deshratn , Blaney Nancy T. , Kumar Mahendra , Baldewicz Teri , Tuttle Raymond S. , Maher Kevin J. , Baum Marianna K. , Shapshak Paul , Fletcher Mary Ann 
Published: December 2019

ABSTRACTA randomized, controlled, clinical trial was conducted to examine the impact of a semistructured, 10-week, once weekly, 90-min/session bereavement support group intervention on immunological, neuroendocrine, and clinical health status in human immunodeficiency virus type 1-seropositive (HIV-1+) and HIV-1-seronegative (HIV-1−) homosexual men, compared to a standard of care control condition. A total of 119 homosexual men (74 HIV-1+and 45 HIV-1−) were assessed at baseline, 10 weeks, and 6 months follow-up. At the 6-month follow-up assessment, the intervention groups exhibited significant beneficial effects compared to controls on changes in CD4 cell, total T-lymphocyte, and total lymphocyte counts, when baseline levels, antiretroviral medication use, CDC stage of disease, and other potentially confounding factors were accounted for. There was no statistically significant effect on the CD4/CD8 ratio or on the CD8 cell count. The effect on CD4 cell count was associated with group attendance and with changes in plasma cortisol level. Plasma cortisol levels decreased significantly among intervention subjects, compared to controls. A significantly reduced number of health care visits over the 6-month follow-up period among the intervention subjects supported the clinical relevance of the immunological changes observed for both HIV-1+and HIV-1−individuals. These results indicate that behavioral interventions may have salutary immunological and clinical health effects following bereavement among HIV-1-infected individuals. The effect in HIV-1−individuals suggests that this bereavement support group intervention might have similar salutary effects in the general population. Potential effects of such interventions on clinical HIV disease progression are of interest and should be studied.