bluuebunny/crossref_metadata_2025_split huggingface dataset:
Analysis of Complement Fixation and Commercial Enzyme Immunoassays for Detection of Antibodies to
Mycoplasma pneumoniae
in Human Serum
Authors: Thacker W. Lanier , Talkington Deborah F. 
Published: July 2002

ABSTRACT

The Meridian ImmunoCard (IC), GenBio ImmunoWELL-IgM, and Remel EIA commercial antibody tests are qualitative enzyme immunoassays that detect antibodies to
Mycoplasma pneumoniae
in serum. These tests were compared to an
M. pneumoniae
complement fixation (CF) assay, which uses a commercially available antigen component. The Meridian IC and the ImmunoWELL-IgM detect immunoglobulin M (IgM) only; the Remel EIA and the CF test detect both IgM and IgG antibodies. Detection of specific IgM antibody, which appears early in infection, can be, but is not always, indicative of a recent or current infection. Paired serum samples from 64 adult patients with probable
M. pneumoniae
infection were examined with each of the four tests. Thirty (47%) of the 64 acute-phase sera were IgM positive by Meridian IC, 26 (41%) were positive by Remel EIA, 24 (38%) were positive by CF, and 15 (23%) were positive by ImmunoWELL-IgM. When both the acute- and convalescent-phase serum samples from each patient were examined, 61 (95%) of the 64 patients were positive by CF, 60 patients (94%) were positive by Remel EIA, 52 patients (81%) were IgM positive by the Meridian IC, and 29 patients (45%) were IgM positive by the ImmunoWELL-IgM assay. The Meridian IC was more sensitive than the other tests for early detection of IgM antibodies. However, after examining paired serum samples, we concluded that the detection of IgM alone may not be useful for all cases of mycoplasma infection, especially in an adult population.
Structural and Immunological Characteristics of a 28-Kilodalton Cruzipain-Like Cysteine Protease ofParagonimus westermaniExpressed in the Definitive Host Stage
Authors: Yun Doo-Hee , Chung Joon-Yong , Chung Young-Bae , Bahk Young-Yil , Kang Shin-Yong , Kong Yoon , Cho Seung-Yull 
Published: July 2002

ABSTRACTA complete cDNA sequence encoding a 28-kDa cruzipain-like cysteine protease of adultParagonimus westermani, termed Pw28CCP, was isolated from an adult cDNA library. The cDNA contained a single open reading frame of 975 bp encoding 325 amino acids, which exhibited the structural motif and domain organization characteristic of cysteine proteases of non-cathepsin Bs including a hydrophobic signal sequence, an ERFNIN motif, and essential cysteine residues as well as active sites in the mature catalytic region. Analysis of its phylogenetic position revealed that this novel enzyme belonged to the cruzipain-like cysteine proteases. The sequence of the first 13 amino acids predicted from the mature domain of Pw28CCP was in accord with that determined from the native 28-kDa enzyme purified from the adult worm. Expression of Pw28CCP was observed specifically in juvenile and adult worms, with a location in the intestinal epithelium, suggesting that this enzyme could be secreted and involved in nutrient uptake and immune modulation. The recombinant protein expressed inEscherichia coliwas used to assess antigenicity by immunoblotting with sera from patients with active paragonimiasis and from those with other parasitic infections. The resulting sensitivity of 86.2% (56 of 65 samples) and specificity of 98% (147 of 150 samples) suggest its potential as an antigen for use in immunodiagnosis.
Cell-Mediated Immune Response to Tuberculosis Antigens: Comparison of Skin Testing and Measurement of In Vitro Gamma Interferon Production in Whole-Blood Culture
Authors: Katial Rohit K. , Hershey Joyce , Purohit-Seth Tejashiri , Belisle John T. , Brennan Patrick J. , Spencer John S. , Engler Renata J. M. 
Published: July 2002

ABSTRACTAlthough delayed-type hypersensitivity skin testing with tuberculin purified protein derivative (PPD) is the standard for tuberculosis screening, its variability suggests the need for a more sensitive, noninvasive test. An in vitro whole-blood assay has been proposed as an alternative. Using health care worker volunteers, we confirmed the correlation between PPD skin test (PPD-ST) results (positive, induration of >15 mm) and a standardized gamma interferon (IFN-γ) assay, QuantiFERON-TB (Q-IFN), manufactured by CSL Biosciences in Australia, and we evaluatedMycobacterium tuberculosisculture subfractions as potential substitutes for PPD. Twenty healthy volunteers with positive PPD-ST results and 20 PPD-ST-negative controls were enrolled. Whole blood was cultured with human PPD antigens (HuPPD),Mycobacterium aviumcomplex (MAC) PPD, phytohemagglutinin (PHA), and fourM. tuberculosisculture subfractions: low-molecular-weight culture, filtrate, culture filtrate without lipoarabinomannan, soluble cell wall proteins, and cytosolic proteins, all developed fromM. tuberculosisstrain H37RV. Secretion of IFN-γ (expressed as international units per milliliter) was measured by an enzyme immunoassay. The PPD or subculture fraction response as a percentage of the PHA response was used to determine positivity. Sixteen of 20 PPD-ST-positive individuals were classified asM. tuberculosispositive by Q-IFN, and 1 was classified as MAC positive. Sixteen of 20 PPD-ST-negative individuals wereM. tuberculosisnegative by Q-IFN, 2 were MAC positive, and 2 wereM. tuberculosispositive. The tuberculosis culture subfractions stimulated IFN-γ production in PPD-ST-positive volunteers, and significant differences could be seen between the two PPD-ST groups with all subfractions except soluble cell wall protein; however, the response was variable and no better than the Q-IFN PPD. The agreement between the Q-IFN test and the PPD-ST was good (Cohen's kappa = 0.73). The Q-IFN assay can be a useful tool in further studies of immune responses toM. tuberculosisantigens.
Two Methods for Rapid Serological Diagnosis of Acute Leptospirosis
Authors: Levett Paul N. , Branch Songee L. , Whittington Carol U. , Edwards Charles N. , Paxton Helene 
Published: July 2002

ABSTRACT
Leptospirosis is a common and underdiagnosed zoonosis. Two rapid assays for serological diagnosis of acute leptospirosis in diagnostic laboratories, the immunoglobulin M (IgM)-dipstick assay and the indirect hemagglutination assay (IHA), were evaluated and compared with standard assays. Sera were examined from 104 patients admitted to a hospital for investigation in a leptospirosis diagnostic protocol. Specimens for serology were taken on days 1 and 4 of the patients' hospital stay. Antibodies were detected using an IgM-enzyme-linked immunosorbent assay (ELISA), microscopic agglutination test (MAT), an IgM-dipstick assay, and an IHA. Fifty-one patients were found to have leptospirosis. The sensitivity of the IgM-dipstick assay was 98%, its specificity was 90.6%, its positive predictive value was 90.9%, and its negative predictive value was 98%. The sensitivity of the IHA was 92.2%, its specificity was 94.4%, its positive predictive value was 95.9%, and its negative predictive value was 92.7%. The standard IgM-ELISA and MAT, were positive in the first samples tested from 67 and 55% of the cases, respectively, and the rapid IgM-dipstick assay and IHA were positive in 71 and 49%, respectively, in the first sample tested. Both rapid assays are highly sensitive and specific. Neither requires specialized equipment, and both are suitable for use in diagnostic laboratories.
Suppression of Endotoxin- and Staphylococcal Exotoxin-Induced Cytokines and Chemokines by a Phospholipase C Inhibitor in Human Peripheral Blood Mononuclear Cells
Authors: Krakauer Teresa 
Published: July 2002

ABSTRACTExcessive release of proinflammatory cytokines from cells stimulated with lipopolysaccharide (LPS) or staphylococcal exotoxin (SE) mediates the pathophysiologic manifestations of septic shock. Tricyclodecan-9-yl (D609), an inhibitor of phosphatidylcholine-specific phospholipase C, suppressed LPS- or SE-induced cytokines and chemokines in human peripheral blood mononuclear cells. These data suggest a potential role for D609 in the treatment of septic shock.
Celiac Disease-Associated Autoimmune Endocrinopathies
Authors: Kumar Vijay , Rajadhyaksha Manoj , Wortsman Jacobo 
Published: July 2002

ABSTRACTCeliac disease (CD) is an autoimmune disorder induced by gluten intake in genetically susceptible individuals. It is characterized by the presence of serum antibodies to endomysium, reticulin, gliadin, and tissue transglutaminase. The incidence of CD in various autoimmune disorders is increased 10- to 30-fold in comparison to the general population, although in many cases CD is clinically asymptomatic or silent. The identification of such cases with CD is important since it may help in the control of type I diabetes or endocrine functions in general, as well as in the prevention of long-term complications of CD, such as lymphoma. It is believed that CD may predispose an individual to other autoimmune disorders such as type I diabetes, autoimmune thyroid, and other endocrine diseases and that gluten may be a possible trigger. The onset of type I diabetes at an early age in patients with CD, compared to non-CD, and the prevention or delay in onset of diabetes by gluten-free diet in genetically predisposed individuals substantiates this antigen trigger hypothesis. Early identification of CD patients in highly susceptible population may result in the treatment of subclinical CD and improved control of associated disorders.
Enzyme-Linked Immunospot Assays Provide a Sensitive Tool for Detection of Cytokine Secretion by Monocytes
Authors: Kouwenhoven Mathilde , Özenci Volkan , Teleshova Natalia , Hussein Yassir , Huang Yu-Min , Eusebio Alexandre , Link Hans 
Published: July 2002

ABSTRACTBlood monocytes as well as tissue-differentiated macrophages play a pivotal role in controlling immune reactions. Monocytes regulate the extent, nature, and duration of immune responses by secretion of cytokines. Interleukin 6 (IL-6), tumor necrosis factor alpha (TNF-α), IL-10, and IL-12 are of particular interest, since IL-12 shifts the immune response towards a Th1 type, facilitating the production of, e.g., TNF-α and IL-6, while IL-10 counteracts Th1 responses and promotes the production of Th2-related cytokines such as IL-4. A tight regulation of these four cytokines keeps the balance and decides whether Th1 or Th2 will predominate in immune reactions. Enzyme-linked immunospot (ELISPOT) assays are among the most-sensitive and -specific methods available for cytokine research. They permit ex vivo identification of individual cells actively secreting cytokines. In the present study we prepared monocytes from healthy subjects' blood and adapted ELISPOT assays to define optimal conditions to detect and enumerate monocytes secreting IL-6, TNF-α, IL-10, and IL-12. The optimal time for monocyte incubation was 24 h, and optimal monocyte numbers (in cells per well) were 2,000 for IL-6, 1,000 for TNF-α, 50,000 for IL-10, and 100,000 for enumeration of IL-12 secreting monocytes. Among healthy subjects, 10% ± 5% of the monocytes secreted IL-6, 12% ± 12% secreted TNF-α, 0.1% ± 0.1% secreted IL-10, and 0.2% ± 0.3% secreted IL-12 (values are means ± standard deviations). In conclusion, ELISPOT assays constitute a valuable tool to enumerate monocytes secreting IL-6, TNF-α, IL-10, and IL-12 and probably to enumerate monocytes secreting other cytokines and proteins.
Immunobiological Effects of Fumonisin B1 in Experimental Subchronic Mycotoxicoses in Rats
Authors: Theumer M. G. , López A. G. , Masih D. T. , Chulze S. N. , Rubinstein H. R. 
Published: July 2002

ABSTRACTFumonisin B1 (FB1), the principal secondary metabolite produced by the fungusFusarium verticillioides(Gibberella fujikuroimating population A), is a potent toxin that can be found in fungus-contaminated corn and corn-based food products. We have investigated the immunobiological effects of subchronic dietary exposure to FB1 in male Wistar rats. Animals were fed with diets containing 0 (control) or 100 ppm of FB1 for 12 weeks. The total FB1 intake on day 90 was 810 mg/kg of body weight. Food consumption, body weight, and body weight gain on day 90 were reduced in animals exposed to FB1. Histopathologic changes consisted of histiocytic perivascular infiltrate and an increased number of Kupffer cells in the liver, necrosis and apoptosis of tubular epithelial cells in the kidney, and increased mitotic figures and lymphocytic infiltrate in the small intestine. Serum enzyme alkaline phosphatase was significantly elevated in rats fed FB1, while triglyceride levels decreased compared to controls. Treatment with FB1 in vivo or in vitro did not have a significant effect on mitogen-induced proliferation of spleen mononuclear cells. However, increased levels of interleukin-4 (IL-4) and decreased levels of IL-10 were released by these cells in culture compared to controls. FB1 in vivo or in vitro decreased the hydrogen peroxide (H2O2) released by peritoneal macrophages, while no changes in levels of superoxide anion produced by total peritoneal cells were detected. The results from the present work demonstrate that subchronic FB1 intake could affect the small intestine and alter the interleukin profile and some main functions of macrophages in antitumor activity.
Genotypic Testing for Human Immunodeficiency Virus Type 1 Drug Resistance
Authors: Shafer Robert W. 
Published: July 2002

SUMMARYThere are 16 approved human immunodeficiency virus type 1 (HIV-1) drugs belonging to three mechanistic classes: protease inhibitors, nucleoside and nucleotide reverse transcriptase (RT) inhibitors, and nonnucleoside RT inhibitors. HIV-1 resistance to these drugs is caused by mutations in the protease and RT enzymes, the molecular targets of these drugs. Drug resistance mutations arise most often in treated individuals, resulting from selective drug pressure in the presence of incompletely suppressed virus replication. HIV-1 isolates with drug resistance mutations, however, may also be transmitted to newly infected individuals. Three expert panels have recommended that HIV-1 protease and RT susceptibility testing should be used to help select HIV drug therapy. Although genotypic testing is more complex than typical antimicrobial susceptibility tests, there is a rich literature supporting the prognostic value of HIV-1 protease and RT mutations. This review describes the genetic mechanisms of HIV-1 drug resistance and summarizes published data linking individual RT and protease mutations to in vitro and in vivo resistance to the currently available HIV drugs.
Innate Immunity toMycobacterium tuberculosis
Authors: van Crevel Reinout , Ottenhoff Tom H. M. , van der Meer Jos W. M. 
Published: July 2002

SUMMARYThe different manifestations of infection with Mycobacterium tuberculosis reflect the balance between the bacillus and host defense mechanisms. Traditionally, protective immunity to tuberculosis has been ascribed to T-cell-mediated immunity, with CD4+T cells playing a crucial role. Recent immunological and genetic studies support the long-standing notion that innate immunity is also relevant in tuberculosis. In this review, emphasis is on these natural, innate host defense mechanisms, referring to experimental data (e.g., studies in gene knockout mice) and epidemiological, immunological, and genetic studies in human tuberculosis. The first step in the innate host defense is cellular uptake of M. tuberculosis, which involves different cellular receptors and humoral factors. Toll-like receptors seem to play a crucial role in immune recognition of M. tuberculosis, which is the next step. The subsequent inflammatory response is regulated by production of pro- and anti-inflammatory cytokines and chemokines. Different natural effector mechanisms for killing of M. tuberculosis have now been identified. Finally, the innate host response is necessary for induction of adaptive immunity to M. tuberculosis. These basic mechanisms augment our understanding of disease pathogenesis and clinical course and will be of help in designing adjunctive treatment strategies.
Mycobacterium bovisBCG Induces Similar Immune Responses and Protection by Rectal and Parenteral Immunization Routes
Authors: M Abolhassani , Lagranderie M. , Chavarot P. , Balazuc A.-M. , Marchal G. 
Published: July 2002

ABSTRACTWe compared cellular immune responses to rectal, subcutaneous, and intradermal administration ofMycobacterium bovisBCG for 5 to 20 weeks in mice, guinea pigs, and macaques. Strong lymphoproliferative responses were induced in spleen cells after in vitro stimulation with purified protein derivative in guinea pigs and macaques, whatever the route of immunization. Comparable high numbers of gamma interferon- and tumor necrosis factor alpha-producing cells were found in the spleen after rectal, subcutaneous, and intradermal immunization of mice and macaques. Similar levels of precursors of cytotoxic T lymphocytes specific for mycobacterial antigens were observed in mice for all immunization routes. In macaques, cytotoxic activity, determined only at the end of the experiment (20 weeks), was similar after rectal and intradermal immunization. Six months after immunization, rectal and subcutaneous routes induced in mice similar levels of protective immunity against challenge with a virulentMycobacterium tuberculosisstrain (H37Rv). Rectal immunization gave immune responses and protective capacity similar to those for parenteral immunization and seemed to be a promising new route of vaccination against tuberculosis; in our study, immunization via the rectal route never induced side effects associated with parenteral routes (axillary adenitis) and could also effectively reduce the risks of viral transmission associated with unsafe injections in the developing world.
Peritoneal Culture Alters
Streptococcus pneumoniae
Protein Profiles and Virulence Properties
Authors: Orihuela Carlos J. , Janssen Rob , Robb Christopher W. , Watson David A. , Niesel David W. 
Published: July 2002

ABSTRACT

We have examined the properties of
Streptococcus pneumoniae
cultured in the murine peritoneal cavity and compared its virulence-associated characteristics to those of cultures grown in vitro. Analysis of mRNA levels for specific virulence factors demonstrated a 2.8-fold increase in
ply
expression and a 2.2-fold increase in
capA3
expression during murine peritoneal culture (MPC). Two-dimensional gels and immunoblots using convalescent-phase patient sera and murine sera revealed distinct differences in protein production in vivo (MPC). MPC-grown pneumococci adhered to A549 epithelial cell lines at levels 10-fold greater than those cultured in vitro.
imp
A, a Gene Coding for an Inner Membrane Protein, Influences Colonial Morphology of
Actinobacillus actinomycetemcomitans
Authors: Mintz Keith P. , Fives-Taylor Paula M. 
Published: July 2002

ABSTRACT

Directed mutagenesis of a gene coding for a membrane protein of the periodontopathogen
Actinobacillus actinomycetemcomitans
was achieved by conjugation. The gene was disrupted by insertion of an antibiotic cassette into a unique endonuclease restriction sequence engineered by inverse PCR. The disrupted gene was cloned into a conjugative plasmid and transferred from
Escherichia coli
to
A. actinomycetemcomitans
. The allelic replacement mutation resulted in the loss of a 22-kDa inner membrane protein. The loss of this protein (ImpA) resulted in changes in the outer membrane protein composition of the bacterium. Concurrent with the mutation in
impA
was a change in the pattern of growth of the mutant bacteria in broth cultures. The progenitor bacteria grew as a homogeneous suspension of cells compared to a granular, autoaggregating adherent cell population described for the mutant bacteria. These data suggest that ImpA may play a regulatory role or be directly involved in protein(s) that are exported and associated with colony variations in
A. actinomycetemcomitans.
Sialylation of Lipooligosaccharide Cores Affects Immunogenicity and Serum Resistance of
Campylobacter jejuni
Authors: Guerry Patricia , Ewing Cheryl P. , Hickey Thomas E. , Prendergast Martina M. , Moran Anthony P. 
Published: July 2002

ABSTRACT

Three genes involved in biosynthesis of the lipooligosaccharide (LOS) core of
Campylobacter jejuni
MSC57360, the type strain of the HS:1 serotype, whose structure mimics GM
2
ganglioside, have been cloned and characterized. Mutation of genes encoding proteins with homology to a sialyl transferase (
cstII
) and a putative
N
-acetylmannosamine synthetase (
neuC1
), part of the biosynthetic pathway of
N
-acetylneuraminic acid (NeuNAc), have identical phenotypes. The LOS cores of these mutants display identical changes in electrophoretic mobility, loss of reactivity with cholera toxin (CT), and enhanced immunoreactivity with a hyperimmune polyclonal antiserum generated against whole cells of
C. jejuni
MSC57360. Loss of sialic acid in the core of the
neuC1
mutant was confirmed by fast atom bombardment mass spectrometry. Mutation of a gene encoding a putative β-1,4-
N
-acetylgalactosaminyltransferase (Cgt) resulted in LOS cores intermediate in electrophoretic mobility between that of wild type and the mutants lacking NeuNAc, loss of reactivity with CT, and a reduced immunoreactivity with hyperimmune antiserum. Chemical analyses confirmed the loss of
N
-acetylgalactosamine (GalNAc) and the presence of NeuNAc in the
cgt
mutant. These data suggest that the Cgt enzyme is capable of transferring GalNAc to an acceptor with or without NeuNAc and that the Cst enzyme is capable of transferring NeuNAc to an acceptor with or without GalNAc. A mutant with a nonsialylated LOS core is more sensitive to the bactericidal effects of human sera than the wild type or the mutant lacking GalNAc.
Differential Alteration in Intestinal Epithelial Cell Expression of Toll-Like Receptor 3 (TLR3) and TLR4 in Inflammatory Bowel Disease
Authors: Cario Elke , Podolsky Daniel K. 
Published: July 2002

ABSTRACTInitiation and perpetuation of the inflammatory intestinal responses in inflammatory bowel disease (IBD) may result from an exaggerated host defense reaction of the intestinal epithelium to endogenous lumenal bacterial flora. Intestinal epithelial cell lines constitutively express several functional Toll-like receptors (TLRs) which appear to be key regulators of the innate response system. The aim of this study was to characterize the expression pattern of TLR2, TLR3, TLR4, and TLR5 in primary intestinal epithelial cells from patients with IBD. Small intestinal and colonic biopsy specimens were collected from patients with IBD (Crohn's disease [CD], ulcerative colitis [UC]) and controls. Non-IBD specimens were assessed by immunofluorescence histochemistry using polyclonal antibodies specific for TLR2, TLR3, TLR4, and TLR5. Primary intestinal epithelial cells (IEC) of normal mucosa constitutively expressed TLR3 and TLR5, while TLR2 and TLR4 were only barely detectable. In active IBD, the expression of TLR3 and TLR4 was differentially modulated in the intestinal epithelium. TLR3 was significantly downregulated in IEC in active CD but not in UC. In contrast, TLR4 was strongly upregulated in both UC and CD. TLR2 and TLR5 expression remained unchanged in IBD. These data suggest that IBD may be associated with distinctive changes in selective TLR expression in the intestinal epithelium, implying that alterations in the innate response system may contribute to the pathogenesis of these disorders.