bluuebunny/crossref_metadata_2025_split huggingface dataset:
Enhancement by Ampicillin of Antibody Responses Induced by a Protein Antigen and a DNA Vaccine Carried by Live-Attenuated
Salmonella enterica
Serovar Typhi
Authors: Woo Patrick C. Y. , Tsoi Hoi-Wah , Leung Harry C. H. , Wong Lei-Po , Wong Samson S. Y. , Chan Eric , Yuen Kwok-Yung 
Published: July 2002

ABSTRACT

Live-attenuated
Salmonella
species are effective carriers of microbial antigens and DNA vaccines. In a mouse model, the immunoglobulin M (IgM) and total antibody levels directed toward the lipopolysaccharide of
Salmonella enterica
serovar Typhi were significantly enhanced at day 21 after oral immunization with live-attenuated serovar Typhi (strain Ty21a) when ampicillin was concomitantly administered (
P
< 0.05 and
P
< 0.005, respectively). The heat-killed Ty21a-stimulated lymphocyte proliferation indices for the ampicillin group at day 21 were significantly higher than those for the normal saline (NS) group (
P
< 0.005,
P
< 0.001, and
P
< 0.01) for all three doses of antigen (10
4
, 10
5
, and 10
6
heat-killed Ty21a per well, respectively). The 50% lethal doses for mice from the ampicillin and NS groups immunized with Ty21a with pBR322 after wild-type serovar Typhi challenge on day 24 were 3.4 × 10
7
and 5.0 × 10
6
CFU, respectively. The fecal bacterial counts for the ampicillin group at days 1, 3, and 5 were significantly lower than those for the NS group (
P
< 0.01,
P
< 0.01, and
P
< 0.05, respectively), and there was a trend toward recovery of Ty21a in a larger number of mice from the ampicillin group than from the NS group. Furthermore, the IgG2a levels directed toward tetanus toxoid were significantly enhanced at days 7 and 21 after oral immunization with Ty21a that carried the fragment c of tetanus toxoid when ampicillin was concomitantly administered (
P
< 0.05 and
P
< 0.005, respectively), and the IgM and total hepatitis B surface antibody levels were significantly enhanced at days 7 (
P
< 0.005 and
P
< 0.05, respectively) and 21 (
P
< 0.01 and
P
< 0.05, respectively) after oral immunization with Ty21a that carried the DNA vaccine that encodes hepatitis B surface antigen when ampicillin was concomitantly administered. The present observation may improve the efficacy of the protein antigens and DNA vaccines carried in live-attenuated bacteria, and further experiments should be carried out to determine the best antibiotics and dosage regimen to be used, as well as the best carrier system for individual protein antigens and DNA vaccines.
Evaluation of Two Slide Agglutination Tests and a Novel Immunochromatographic Assay for Rapid Diagnosis of Infectious Mononucleosis
Authors: Gómez M. Concepción , Nieto Jose A. , Escribano M. Angeles 
Published: July 2002

ABSTRACT
The results of three tests used for the rapid diagnosis of infectious mononucleosis (IM) were compared with those of Epstein-Barr virus-specific serology. The sensitivities ranged from 15 to 33% in children under 13 years of age and from 59 to 81% in patients over 13 years. The specificities ranged from 86 to 100% in both age groups. These tests have a poor sensitivity for the diagnosis of IM, particularly in children.
Brucella abortus
RB51 and Hot Saline Extract from
Brucella ovis
as Antigens in a Complement Fixation Test Used To Detect Sheep Vaccinated with
Brucella abortus
RB51
Authors: Adone Rosanna , Ciuchini Franco 
Published: July 2002

ABSTRACT

The efficacy of
Brucella abortus
RB51 and hot saline extract (HSE) from
Brucella ovis
as antigens in complement fixation (CF) tests was comparatively evaluated in detecting immune responses of sheep vaccinated with
B. abortus
strain RB51. For this study, four 5-month-old sheep were vaccinated subcutaneously with 5 × 10
9
CFU of RB51, and two sheep received saline. Serum samples collected at different times after vaccination were tested for the presence of antibodies to RB51 by a CF test with RB51 as antigen, previously deprived of anticomplementary activity, and with HSE antigen, which already used as the official antigen to detect
B. ovis
-infected sheep. The results showed that vaccinated sheep developed antibodies which reacted weakly against HSE antigen and these antibodies were detectable for 30 days after vaccination. However, antibodies to RB51 could be detected for a longer period after vaccination by using homologous RB51 antigen in CF tests. In fact, high titers were still present at 110 days postvaccination with RB51 antigen. Sera from sheep naturally infected with
B. ovis
also reacted to RB51 but gave lower titers than those detected by HSE antigen. As expected, all sera from RB51-vaccinated sheep remained negative when tested with standard S-type
Brucella
standard antigens.
Development of a Novel Screen for Protease Inhibitors
Authors: Gillim L. , Gusella G. L. , Vargas J. , Marras D. , Klotman M. E. , Cara A. 
Published: July 2002

ABSTRACT
We have developed a novel plasmid-based, quantitative, in vitro screen to test the protease-inhibiting activities of existing and newly discovered agents.
Comparison of Immulite with Vidas for Detection of Infection in a Low-Prevalence Population of Pregnant Women in The Netherlands
Authors: Vlaspolder F. , Singer P. , Smit A. , Diepersloot R. J. A. 
Published: July 2002

ABSTRACT

A comparative evaluation of the Vidas system (bioMérieux, Marcy l'Etoile, France) and the Immulite System (Diagnostic Products Corporation) was performed using 500 prospectively collected serum samples. As part of a routine antenatal screening program, these samples were tested for hepatitis B surface antigen, and immunoglobulin G (IgG) and IgM antibodies to
Toxoplasma gondii
and rubella virus. The overall agreement between the two assay systems ranged from 98.0 to 99.8%. After discrepancy analysis the outcome in terms of relative sensitivity and specificity varied from 97.5 to 100%.
Intra- and Interlaboratory Variabilities of Results Obtained with the Quantiplex Human Immunodeficiency Virus Type 1 RNA bDNA Assay, Version 3.0
Authors: Kellogg James A. , Atria Peter V. , Sanders Jeffrey C. , Eyster M. Elaine 
Published: July 2002

ABSTRACT

Normal assay variation associated with bDNA tests for human immunodeficiency virus type 1 (HIV-1) RNA performed at two laboratories with different levels of test experience was investigated. Two 5-ml aliquots of blood in EDTA tubes were collected from each patient for whom the HIV-1 bDNA test was ordered. Blood was stored for no more than 4 h at room temperature prior to plasma separation. Plasma was stored at −70°C until transported to the Central Pennsylvania Alliance Laboratory (CPAL; York, Pa.) and to the Hershey Medical Center (Hershey, Pa.) on dry ice. Samples were stored at ≤−70°C at both laboratories prior to testing. Pools of negative (donor), low-HIV-1-RNA-positive, and high-HIV-1-RNA-positive plasma samples were also repeatedly tested at CPAL to determine both intra- and interrun variation. From 11 August 1999 until 14 September 2000, 448 patient specimens were analyzed in parallel at CPAL and Hershey. From 206 samples with results of ≥1,000 copies/ml at CPAL, 148 (72%) of the results varied by ≤0.20 log
10
when tested at Hershey and none varied by >0.50 log
10
. However, of 242 specimens with results of <1,000 copies/ml at CPAL, 11 (5%) of the results varied by >0.50 log
10
when tested at Hershey. Of 38 aliquots of HIV-1 RNA pool negative samples included in 13 CPAL bDNA runs, 37 (97%) gave results of <50 copies/ml and 1 (3%) gave a result of 114 copies/ml. Low-positive HIV-1 RNA pool intrarun variation ranged from 0.06 to 0.26 log
10
while the maximum interrun variation was 0.52 log
10
. High-positive HIV-1 RNA pool intrarun variation ranged from 0.04 to 0.32 log
10
, while the maximum interrun variation was 0.55 log
10
. In our patient population, a change in bDNA HIV-1 RNA results of ≤0.50 log
10
over time most likely represents normal laboratory test variation. However, a change of >0.50 log
10
, especially if the results are >1,000 copies/ml, is likely to be significant.
Characterization of a Monoclonal Antibody That Binds to an Epitope on Soluble Bacterial Peptidoglycan Fragments
Authors: Merkel Glenn J. , Scofield Barbara A. 
Published: July 2002

ABSTRACT

We employed an inhibition-type enzyme-linked immunosorbent assay (ELISA) to characterize a murine immunoglobulin M monoclonal antibody (MAb) that bound soluble macromolecular peptidoglycan (PG). With this ELISA, the MAb was capable of detecting soluble PG concentrations of less than 10 ng/ml. Enzymatic digestion of PG reduced binding by more than 100-fold, implying that the epitope recognized by this antibody depended on repeating subunits within the glycan backbone. Additionally, the MAb bound to epitopes on both O-acetylated and non-O-acetylated PG fragments from gram-negative bacteria, as well as PG fragments from
Staphylococcus aureus
and PG fragments released into the medium by a number of gram-positive and gram-negative bacteria.
Expression of a Novel Protein by Regenerating Hepatocytes and Peripheral Blood Lymphocytes
Authors: Chedid Antonio , Sung Ching C. , Lepe Maria R. , Ahmed Syed A. , Iftikhar Syeda A. , Feller Axel , Beaman Kenneth D. 
Published: July 2002

ABSTRACT
Regeneration and tolerance factor (RTF) is a protein with immunosuppressive activity and is normally present in the thymus and placenta. RTF was measured in the livers of patients with regenerating nodules due to alcoholic cirrhosis and hepatitis C. RTF was expressed in the regenerating nodules of 26 patients with alcoholic cirrhosis. All patients with chronic hepatitis C without cirrhosis failed to express RTF. Flow cytometry revealed upregulation of RTF on the lymphocytes from alcoholic cirrhosis and downregulation in hepatitis C disease.
Immunophenotyping of Peripheral Blood Lymphocytes in Saudi Men
Authors: Al Qouzi Abdulla , Al Salamah Abdulla , Al Rasheed Reem , Al Musalam Abdulla , Al Khairy Khalid , Kheir Osman , Al Ajaji Sulieman , Hajeer Ali H. 
Published: July 2002

ABSTRACT

Flow cytometry is an important tool for the diagnosis and follow-up of immunodeficiency patients, as well as for pateints with leukemia and lymphoma. Lymphocytes and their subsets show variations with race. The aim of this study was to establish reference ranges for lymphocytes and their subsets in an Saudi adult population by using flow cytometry. Blood samples obtained from 209 healthy Saudi men were used for this study. All blood donors were between 18 and 44 years old. Lymphocytes and their subsets were analyzed by flow cytometry, and the absolute and percentage values were calculated. We investigated the expression of T-cell markers (CD3, CD4, and CD8), B cells (CD19), and natural killer cells (CD16 and CD56). The absolute and percent values of each cell subset were compared with published data from different populations by using the Student
t
test. Reference ranges, each expressed as the mean ± the standard deviation, were as follows: leukocytes (6,335 ± 1759), total lymphocytes (2,224 ± 717), CD3 cells (1,618 ± 547), CD4 cells (869 ± 310), CD8 cells (615 ± 278), CD19 cells (230 ± 130), and CD3-CD16
+
/CD56+ cells (262 ± 178). The CD4/CD8 ratio was 1.6 ± 0.7. Our results for B cells, CD4 cells, and CD8 cells and for the CD4/CD8 ratio fell in between the reported results for Ethiopian and Dutch subjects. Our results were also different from previously reported findings in an Saudi adult population that showed no increase in CD8 T cells. We thus establish here the reference ranges for lymphocytes and their subsets in a large cohort of Saudi men. The CD8 cell count was not abnormally high, as previously reported, and fell in between previous results obtained for African and European populations.
Granulocyte Colony-Stimulating Factor Improves Deficient In Vitro Neutrophil Transendothelial Migration in Patients with Advanced Liver Disease
Authors: Fiuza Carmen , Salcedo Magdalena , Clemente Gerardo , Tellado Jose M. 
Published: July 2002

ABSTRACTBacterial infections are frequent complications in patients with liver cirrhosis. Cirrhotic patients present abnormalities in both innate and adaptive immune responses, including a deficient neutrophil recruitment to infected sites. The purpose of this study was to assess neutrophil-endothelium interactions in cirrhotic patients and evaluate the effects of G-CSF on this process. We studied neutrophil adhesion and transendothelial migration in 14 cirrhotic patients and 14 healthy controls. We also analyzed neutrophil expression of the adhesion molecules CD62L and CD11b in whole blood by flow cytometry. Cirrhotic patients expressed higher levels of CD11b than healthy controls, whereas CD62L expression was significantly lower, suggesting exposure of neutrophils to activating agents within the bloodstream. Neutrophils from cirrhotic patients showed increased adhesion to both resting and tumor necrosis factor alpha-stimulated microvascular endothelial cells and decreased transendothelial migration. Granulocyte colony-stimulating factor (G-CSF) (100 ng/ml) significantly enhanced neutrophil adhesion to microvascular endothelial cells in healthy controls but not in cirrhotic patients. G-CSF also significantly improved neutrophil transmigration in cirrhotic patients and healthy controls. In conclusion, cirrhotic patients exhibit increased neutrophil adhesion to microvascular endothelium and deficient transendothelial migration. G-CSF enhances neutrophil transendothelial migration in cirrhotic patients despite having no effect on neutrophil adhesion. Therefore, G-CSF may be able to increase neutrophil recruitment into infected sites in these patients.
Reactivity of Rheumatic Fever and Scarlet Fever Patients' Sera with Group A Streptococcal M Protein, Cardiac Myosin, and Cardiac Tropomyosin: a Retrospective Study
Authors: Jones Kevin F. , Whitehead Stephen S. , Cunningham Madeleine W. , Fischetti Vincent A. 
Published: July 2002

ABSTRACTArchived sera (collected in 1946) from acute rheumatic fever (ARF) and untreated scarlet fever and/or pharyngitis patients were reacted with streptococcal M protein, cardiac myosin, and cardiac tropomyosin. Except for very low levels to tropomyosin, antibodies to other antigens were not elevated in the sera of ARF patients relative to those of non-ARF patients, even though there was roughly equivalent exposure to group A streptococci. This suggests that antibodies to these molecules may not play a central role in the induction of ARF.
Vaccine Efficacy of RecombinantPlasmodium falciparumMerozoite Surface Protein 1 in Malaria-Naive, -Exposed, and/or -RechallengedAotus vociferansMonkeys
Authors: Egan Andrea F. , Blackman Michael J. , Kaslow David C. 
Published: July 2002

ABSTRACTProtection against a lethal challenge infection ofPlasmodium falciparumwas elicited in malaria-naiveAotus vociferansmonkeys by vaccination with the C terminus 19-kDa protein of the major merozoite surface protein (MSP-119) fused to tetanus toxoid universal T-cell epitopes P30 and P2. Three of four monkeys were protected against a 104-parasite challenge. Four monkeys were challenged with 105parasites; one self-cured the infection, two were protected against high parasitemia (<2%) but were treated for severe anemia (hematocrit of <25%), and the fourth was not protected. In this model system, anemia appears to be a manifestation of incomplete protection (prolonged low-level parasitemia). Enzyme-linked immunosorbent assay (ELISA) antibody titers correlated with protection. Antibodies from some protected monkeys inhibited secondary processing of MSP-142to MSP-133and MSP-119. To mimic the repeated reinfections seen in regions where malaria is endemic, a second malaria parasite challenge was administered 4 months later. All P30P2MSP-119-vaccinated monkeys were protected; thus, a single challenge infection may underestimate vaccine efficacy. ELISA antibody titers correlated with protection against a second infection but had decreased compared to the first challenge. As most target populations for asexual blood-stage malaria vaccines will have been exposed to malaria parasites, a malaria parasite-exposed monkey was vaccinated with P30P2MSP-119. This monkey was completely protected, while a malaria parasite-naive P30P2MSP-119-vaccinated monkey self-cured a low-grade parasitemia. Prior malaria parasite infection primed the production of anti-native MSP-119antibodies, which were boosted by vaccination with recombinant P30P2MSP-119. Preliminary data suggest that immunogenicity studies of vaccines designed for malaria parasite-exposed populations should also be conducted in malaria parasite-exposed subjects.
RpmA Is Required for Nonopsonic Phagocytosis of
Pseudomonas aeruginosa
Authors: Simpson David A. , Speert David P. 
Published: July 2002

ABSTRACT

Pseudomonas aeruginosa
causes severe respiratory tract infections in patients with cystic fibrosis (CF). We have been examining nonopsonic phagocytosis of
P. aeruginosa
by macrophages. To study the
P. aeruginosa
-macrophage interaction at the molecular level, we have constructed a transposon Tn
5
G bank in a clinical isolate of
P. aeruginosa
(strain 4020) and identified mutants resistant to nonopsonic phagocytosis. Phagocytosis-resistant mutants were enriched by passaging the transposon bank over 18 macrophage monolayers. Of 900 individual mutants isolated from this enriched pool in a nonopsonic phagocytosis assay, we identified 85 putative mutants that were resistant to phagocytosis. In this study, we have characterized one of these transposon mutants,
P. aeruginosa
4020 H27A, which was poorly ingested. H27A possessed a Tn
5
G insertion in a gene encoding a protein with homology to the MotA proteins of several species of bacteria. We have called this gene
rpmA
for required for phagocytosis by macrophages. RpmA is one of two MotA paralogs in
P. aeruginosa
. This
rpmA
::Tn
5
G mutant was motile both on agar plates and in visual examination of wet mounts. The phagocytosis defect was partially complemented by providing the
rpmA
gene in
trans
and fully complemented when both
rpmA
and
rpmB
were provided. A
rpmA
null mutant was ingested by macrophages similar to the H27A transposon mutant. These data suggest that the
rpmA
and
rpmB
gene products are required for the efficient ingestion of
P. aeruginosa
by macrophages.
Coimmunization with Complementary Glucosyltransferase Peptides Results in Enhanced Immunogenicity and Protection against Dental Caries
Authors: Taubman Martin A. , Smith Daniel J. , Holmberg Cynthia J. , Eastcott Jean W. 
Published: July 2002

ABSTRACT

Peptide constructs from the catalytic (CAT) and glucan-binding (GLU) regions of the mutans streptococcal glucosyltransferase enzymes (GTF) can provide immunity to dental caries infection. A strategy of coimmunization was tested to determine whether protection could be enhanced. Rats were immunized with one of the previously described peptide constructs from the CAT or GLU region of the GTF of mutans streptococci or coimmunized with a combination of these constructs (CAT-GLU). Coimmunized animals demonstrated significantly higher serum immunoglobulin G (IgG) and salivary IgA antibody levels to CAT or GTF than rats immunized with either construct alone. To assess the functional significance of coimmunization with these constructs, animals were immunized as above or with
Streptococcus sobrinus
GTF and then infected with
S. sobrinus
to explore the effects of immunization on immunological, microbiological, and disease (dental caries) parameters. Serum antibody from the communized group inhibited
S. sobrinus
GTF-mediated insoluble glucan synthesis in vitro above that of the individual-construct-immunized groups. Immunization with CAT or GLU constructs resulted in significantly reduced dental caries after infection with
S. sobrinus
compared with sham-immunized animals. Coimmunization produced greater reductions in caries than after immunization with either CAT or GLU. Also, significant elevations in lymphocyte proliferative responses to CAT, GLU, and GTF were observed after coimmunization with CAT-GLU compared with the responses after immunization with the individual constructs. The results suggested that increased numbers of memory T cells, which could proliferate to CAT, were generated by coimmunization. The experiments support the functional significance of these GTF domains in dental caries pathogenesis and present coimmunization as a simple alternative to intact GTF to enhance protective immunity against cariogenic microorganisms.
Functional Analysis of Genes in the
rfb
Locus of
Leptospira borgpetersenii
Serovar Hardjo Subtype Hardjobovis
Authors: Bulach Dieter M. , Kalambaheti Thareerat , de la Peña-Moctezuma Alejandro , Adler Ben 
Published: July 2002

ABSTRACT

Lipopolysaccharide (LPS) is a key antigen in immunity to leptospirosis. Its biosynthesis requires enzymes for the biosynthesis and polymerization of nucleotide sugars and the transport through and attachment to the bacterial membrane. The genes encoding these functions are commonly clustered into loci; for
Leptospira borgpetersenii
serovar Hardjo subtype Hardjobovis, this locus, named
rfb
, spans 36.7 kb and contains 31 open reading frames, of which 28 have been assigned putative functions on the basis of sequence similarity. Characterization of the function of these genes is hindered by the fact that it is not possible to construct isogenic mutant strains in
Leptospira
. We used two approaches to circumvent this problem. The first was to clone the entire locus into a heterologous host system and determine if a “recombinant” LPS or polysaccharide was synthesized in the new host. The second approach used putative functions to identify mutants in other bacterial species whose mutations might be complemented by genes on the leptospiral
rfb
locus. This approach was used to investigate the function of three genes in the leptospiral
rfb
locus and demonstrated function for
orfH10
, which complemented a
wbpM
strain of
Pseudomonas aeruginosa
, and
orfH13
, which complemented an
rfbW
strain of
Vibrio cholerae
. However, despite the similarity of OrfH11 to WecC, a
wecC
strain of
E. coli
was not complemented by
orfH11
. The predicted protein encoded by
orfH8
is similar to GalE from a number of organisms. A
Salmonella enterica
serovar Typhimurium strain producing no GalE was used as a background in which
orfH8
produced detectable GalE enzyme activity.
Pseudomonas aeruginosaExoenzyme S Induces Transcriptional Expression of Proinflammatory Cytokines and Chemokines
Authors: Epelman Slava , Bruno Tony F. , Neely Graham G. , Woods Donald E. , Mody Christopher H. 
Published: July 2002

ABSTRACTPseudomonas aeruginosainfection of cystic fibrosis patients causes lung damage that is substantially orchestrated by cytokines. In this study, multi-gene probe analysis was used to characterize the ability of theP. aeruginosamitogen, exoenzyme S, to induce proinflammatory and immunoregulatory cytokines and chemokines. Exoenzyme S strongly induced transcription of proinflammatory cytokines and chemokines (tumor necrosis factor alpha, interleukin-1α [IL-1α], IL-1β, IL-6, IL-8, MIP-1α, MIP-1β, MCP-1, RANTES, and I-309), modest transcription of immunoregulatory cytokines (IL-10 and IL-12p40), and weak transcription of Th1 cytokines (IL-2 and gamma interferon). The response occurred early and subsided without evolving over time. These data suggest that cells responding to exoenzyme S would rapidly express proinflammatory cytokines and chemokines that may contribute to pulmonary inflammation in cystic fibrosis.