bluuebunny/crossref_metadata_2025 huggingface dataset:
Polymeric Display of Immunogenic Epitopes from Herpes Simplex Virus and Transmissible Gastroenteritis Virus Surface Proteins on an Enteroadherent Fimbria
Authors: Rani D. B. Rajini , Bayer Manfred E. , Schifferli Dieter M.
Published: December 2019

The strong immunogenicity of bacterial fimbriae results from their polymeric and proteinaceous nature, and the protective role of these immunogens in experimental or commercial vaccines is associated with their capacity to induce antiadhesive antibodies. Fimbria-mediated intestinal colonization by enteropathogens typically leads to similar antibody responses. The possibility of taking advantage of these properties was investigated by determining whether enteroadhesive fimbriae, like the 987P fimbriae of enterotoxigenic
Escherichia coli
, can serve as carriers for foreign antigens without losing their adhesive characteristics. Random linker insertion mutagenesis of the
fasA
gene encoding the major 987P subunit identified five different mutants expressing wild-type levels of fimbriation. The linker insertion sites of these mutants were used to introduce three continuous segments of viral surface glycoproteins known to be accessible to antibodies. These segments encode residues 11 to 19 or 272 to 279 of herpes simplex virus type 1 (HSV-1) glycoprotein D [gD(11–19) and gD(272–279), respectively] or residues 379 to 388 of the transmissible gastroenteritis virus (TGEV) spike protein [S(379–388)]. Studies of bacteria expressing fimbriae incorporating mutated FasA subunits alone or together with wild-type FasA subunits (hybrid fimbriae) indicated that foreign epitopes were best exported and displayed on assembled fimbriae when they were inserted near the amino terminus of FasA. Fimbriated bacteria expressing FasA subunits carrying the HSV gD(11–19) or the TGEV S(379–388) epitope inserted between the second and third residues of mature FasA elicited high levels of foreign epitope antibodies in all rabbits immunized parenterally. Antibodies against the HSV epitope were also shown to recognize the epitope in the context of the whole gD protein. Because the 987P adhesive subunit FasG was shown to be present on mutated fimbriae and to mediate bacterial attachment to porcine intestinal receptors, polymeric display of foreign epitopes on 987P offers new opportunities to test the potential beneficial effect of enteroadhesion for mucosal immunization and protection against various enteric pathogens.
Changes in Immune Parameters Seen in Gulf War Veterans but Not in Civilians with Chronic Fatigue Syndrome
Authors: Zhang Quanwu , Zhou Xia-Di , Denny Thomas , Ottenweller John E. , Lange Gudrun , LaManca John J. , Lavietes Marc H. , Pollet Claudia , Gause William C. , Natelson Benjamin H.
Published: December 2019

The purpose of this study was to evaluate immune function through the assessment of lymphocyte subpopulations (total T cells, major histocompatibility complex [MHC] I- and II-restricted T cells, B cells, NK cells, MHC II-restricted T-cell-derived naive and memory cells, and several MHC I-restricted T-cell activation markers) and the measurement of cytokine gene expression (interleukin 2 [IL-2], IL-4, IL-6, IL-10, IL-12, gamma interferon [IFN-γ], and tumor necrosis factor alpha [TNF-α]) from peripheral blood lymphocytes. Subjects included two groups of patients meeting published case definitions for chronic fatigue syndrome (CFS)—a group of veterans who developed their illness following their return home from participating in the Gulf War and a group of nonveterans who developed the illness sporadically. Case control comparison groups were comprised of healthy Gulf War veterans and nonveterans, respectively. We found no significant difference for any of the immune variables in the nonveteran population. In contrast, veterans with CFS had significantly more total T cells and MHC II+T cells and a significantly higher percentage of these lymphocyte subpopulations, as well as a significantly lower percentage of NK cells, than the respective controls. In addition, veterans with CFS had significantly higher levels of IL-2, IL-10, IFN-γ, and TNF-α than the controls. These data do not support the hypothesis of immune dysfunction in the genesis of CFS for sporadic cases of CFS but do suggest that service in the Persian Gulf is associated with an altered immune status in veterans who returned with severe fatiguing illness.
Identification of Common Lipooligosaccharide Types in Isolates from Patients with Otitis Media by Monoclonal Antibodies against NontypeableHaemophilus influenzae9274
Authors: Ueyama Tomoyo , Gu Xin-Xing , Tsai Chao-Ming , Karpas Arthur B. , Lim David J.
Published: December 2019

Twenty-one murine monoclonal antibodies (MAbs) were induced by nontypeableHaemophilus influenzae(NTHi) 9274. Nineteen MAbs were specific for the lipooligosaccharide (LOS) as determined by enzyme-linked immunosorbent assay (ELISA) and Western blot analysis. When the MAbs were assayed with five LOS prototype strains by ELISA, all bound to strain 3198 LOS (type III), while six of the MAbs were also reactive with LOSs from strain 1479 (type I), 5657 (type IV), or 7502 (type V). Ten MAbs had complement-mediated bactericidal activity, and three MAbs were opsonophagocytic against the homologous strain. Five LOS MAbs with different specificities were used to analyze 155 NTHi clinical isolates from the United States and from Japan. These isolates were classified into nine groups by ELISA. Only four isolates (2.6%) were not recognized by any of the five MAbs. Most of the isolates (91.6%) were in four groups which bound three of the five MAbs. One of three MAbs, 6347C11, had strong activity against the homologous strain and was also bactericidal to 45 clinical isolates (29%) which belonged to the four common patterns (25 belonged to pattern 1). These data indicate that these MAbs can be used for LOS typing in which almost all NTHi strains can be typed according to the LOS antigenicity. Among NTHi, at least one conserved LOS epitope which is a target of bactericidal antibodies exists. We conclude that strain 9274 LOS, which is the target for bactericidal antibodies, is a candidate for LOS-based NTHi vaccines.
Phagocytosis of
Vibrio cholerae
O139 Bengal by Human Polymorphonuclear Leukocytes
Authors: Albert M. John , Qadri Firdausi , Bhuiyan Nurul A. , Ahmad Shaikh M. , Ansaruzzaman M. , Weintraub Andrej
Published: December 2019

Capsulated bacteria exhibit serum (complement) resistance and resistance to phagocytosis, which result in disseminated infections.
Vibrio cholerae
O139 strains possess a thin capsule and have been found to be partially serum resistant in a previous study. In the present study, compared to a standard capsulated
Klebsiella pneumoniae
strain, which showed total resistance to killing by phagocytosis,
V. cholerae
O139 strains were shown to be only partially resistant, with most strains showing <40% survival. These findings may explain the relative rarity of
V. cholerae
O139 bacteremia in cholera caused by this organism.
Restricted Isotypic Antibody Reactivity to Hepatitis C Virus Synthetic Peptides in Immunocompromised Patients
Authors: Devesa Marisol , de Saez Arlette , León Graciela , Sirit Firelei , Cosson Clarisa , Bermúdez Henry , Liprandi Ferdinando , Noya Oscar , Pujol Flor H.
Published: December 2019

An enzyme immunoassay based on three synthetic peptides from the core, NS4, and NS5 regions of hepatitis C virus allowed the detection of antibodies in 100% of immunocompetent infected patients and in 91% of immunocompromised patients (hemodialysis and hemophiliac patients). Immune impairment seemed to restrict the spectrum of antibody isotypes reacting to the core peptide.
Comparison of the Frequencies and Levels of Human Immunodeficiency Virus Type 1 Markers in Specimens from Chronically Infected Human T-Lymphocyte Cultures and from Patients
Authors: Witt Donald J. , Ginocchio Christine C. , Wang Xue-Ping , Kaufman Mi Khinkhin Soe
Published: December 2019

Together with CD4
+
-cell counts as an indicator of immune function, the use of human immunodeficiency virus type 1 (HIV-1) RNA levels as a direct marker of viral load has gained widespread attention for evaluation of patient clinical status. Results obtained with other HIV-1 markers for this purpose are often inconsistent. This study examined the relationship between various HIV-1 markers by using clinical specimens (plasma) from HIV-1-infected individuals at different stages of disease progression and supernatant fluid from four human T-lymphocyte cell lines chronically infected with HIV-1. Cell culture specimens were collected periodically over 7 days and were tested for HIV-1 RNA levels with a nucleic acid amplification assay, for p24 with an enzyme-linked immunosorbent assay, and for reverse transcriptase activity by isotope uptake. An increase in the level of each marker was observed over the 7-day period with each of the four HIV-1 strains tested (LAV1, HTLV-IIIB, MN, and ARV2); with these specimens, the frequency of detection for each marker was 100%. In the clinical specimens, HIV-1 RNA was detected more often (143 of 183 specimens [78%]) than was p24 (87 of 183 [48%]); little correlation between the levels of the two markers was seen. In these clinical specimens evaluated, CD4
+
-cell counts were better correlated with the frequency and levels of HIV-1 RNA than with p24. In specimens (
n
= 38) collected serially from six HIV-1-infected subjects, HIV-1 RNA was detected more often (33 of 38 [85%]) than p24 (23 of 38 [59%]). When reported by the assays used, the levels of both HIV-1 markers fluctuated over time for each of the subjects. Although the markers correlated in the in vitro systems studied, the observed differences in the correlation of levels and frequencies of HIV-1 markers in vivo indicate that p24 has less clinical utility than does viral load testing when used in conjunction with CD4
+
-cell counts as a measure of immune system functioning.
Gamma Interferon Treatment of Patients with Chronic Granulomatous Disease Is Associated with Augmented Production of Nitric Oxide by Polymorphonuclear Neutrophils
Authors: Åhlin Anders , Lärfars Gerd , Elinder Göran , Palmblad Jan , Gyllenhammar Hans
Published: December 2019

Treatment with gamma-interferon (IFN-γ) is associated with reduced frequency and severity of infections in chronic granulomatous disease (CGD), but the mechanism is unknown. Since the inducible nitric oxide (NO) synthase can be amplified by IFN-γ in murine macrophages, for example, we hypothesized that IFN-γ might modulate NO release from polymorphonuclear neutrophils (PMNs) in patients with CGD. Eight patients with CGD and eight healthy controls were studied. Each patient was given either 50 or 100 μg of IFN-γ per m
2
on two consecutive days. The production of NO from
N
-formyl-methionyl-leucyl-phenylalanine (fMLP)-stimulated PMNs was assessed as the
N
G
-monomethyl-
l
-arginine-inhibitable oxidation of oxyhemoglobin to methemoglobin in the presence of catalase and superoxide dismutase. Prior to IFN-γ treatment, the PMNs from CGD patients produced 372 ± 27 (mean ± standard error of the mean) pmol of NO/10
6
PMNs at 45 min, while the control PMNs produced 343 ± 44 pmol. On day 1 after IFN-γ treatment, NO production increased to 132% ± 25% of that for controls, and on day 3 it reached 360% ± 37% (
P
< 0.001) of that for controls. On day 8, the values still remained higher, 280% ± 78% more than the control values. Likewise, the bactericidal capacity of PMNs increased on day 3. The present data show that IFN-γ treatment of CGD patients is associated with an increased production of NO from PMNs when activated by fMLP. Since these PMNs lack the capacity to produce superoxide anions, it is conceivable that this increase in NO release could be instrumental in augmenting host defense.
Protective Effects of Pertussis Immunoglobulin (P-IGIV) in the Aerosol Challenge Model
Authors: Bruss Jon B. , Siber George R.
Published: December 2019

Pertussis in infants is often severe, resulting in prolonged hospitalization. Treatment is limited to supportive care. Antibiotics do not significantly alter the course of the disease unless administered during the catarrhal phase. Therapies directed at pertussis toxin, a major virulence factor ofBordetella pertussis, may be beneficial. This study uses the aerosol challenge model to further examine the protective effects of P-IGIV, a new intravenous immunoglobulin product, which has high levels of pertussis toxin antibodies. P-IGIV was prepared as a 4% immunoglobulin G (IgG) solution from the pooled donor plasma from donors immunized with inactivated pertussis toxoid. The IgG pertussis toxin antibody concentration in P-IGIV is >7-fold higher than conventional intravenous immunoglobulin products. In the aerosol challenge model, P-IGIV-treated mice exhibited a dose-dependent decrease in mortality when monitored for 28 days postchallenge. P-IGIV in doses of 2,800, 1,400, and 350 mg/kg significantly reduced mortality compared to saline (P< 0.01)- and human IGIV (P< 0.01)-treated controls. The 50% protective dose of pertussis toxin antibodies in P-IGIV was 147 μg/ml. Recovery of weight gain and normalization of leukocyte counts occurred in all P-IGIV-treated groups but did not exhibit dose-dependent characteristics. Even after 7 days of infection, P-IGIV reversed the effects of pertussis in mice. This study provides further evidence that pertussis toxin antibodies not only play a role in passive protection but can also reverse symptoms of established disease in mice. We feel that P-IGIV deserves further evaluation in children hospitalized with severe pertussis.
Serological Diagnosis of Human Cysticercosis by Use of Recombinant Antigens from
Taenia solium
Cysticerci
Authors: Hubert Kerstin , Andriantsimahavandy Abel , Michault Alain , Frosch Matthias , Mühlschlegel Fritz A.
Published: December 2019

A
Taenia solium
metacestode cDNA expression library in the lambda ZAPII vector was screened with pooled sera from patients with neurocysticercosis. Sixty primary clones were identified and shown to belong to two classes. The clones NC-3 and NC-9 did not reveal any significant homologies to sequences deposited in the databases and were further characterized. Both recombinant antigens were expressed as glutathione
S
-transferase fusion proteins and applied for serological diagnosis of human cysticercosis. An enzyme-linked immunosorbent assay was established and evaluated with 27 serum samples of La Réunion and Madagascar patients with cysticercosis. Diagnosis in these patients was established with radiological and serological procedures. For antigen NC-3 a sensitivity of 96.3% and a specificity of 91.5% for the serodiagnosis were achieved. In contrast, the sensitivity of antigen NC-9 was only 33.3%.
Diagnosis of Rickettsial Diseases Using Samples Dried on Blotting Paper
Authors: Fenollar Florence , Raoult Didier
Published: December 2019

The use of filter paper is an inexpensive and convenient method for collecting, storing, and transporting blood samples for serological studies. In addition, samples occupy little space and can be readily transported without refrigeration. Rickettsial diseases often evolve according to an epidemic mode and are now considered reemerging diseases, especially in developing countries, under conditions where fieldwork could be difficult. The suitability of collecting whole-blood specimens on filter paper discs for rickettsial antibody assay was evaluated. Dried blood specimens from 64 individuals with antibodies toCoxiella burnetii,Bartonella quintana, orRickettsia conoriiwere tested for rickettsial antibodies by microimmunofluorescence. Although occasional titers were 1 or 2 dilutions lower than those of tested serum samples, no statistically significant differences were observed. Among patients with negative serology, no false positives were found. This study demonstrated that the recovery of antibodies from finger-stick blood dried on filter paper after elution produces results comparable to those obtained by recovering antibodies from serum. Storing paper samples for 1 month at room temperature or at 4°C did not significantly affect the level of antibodies recovered. This report shows the utility of this sample collection method in developing countries where refrigeration is not possible and venipuncture is problematic.
Immunological Diagnosis of Human Cystic Echinococcosis: Utility of Discriminant Analysis Applied to the Enzyme-Linked Immunoelectrotransfer Blot
Authors: Gadea I. , Ayala G. , Diago M. T. , Cuñat A. , de Lomas J. García
Published: December 2019

An enzyme-linked immunoelectrotransfer blot for the diagnosis of human hydatid disease was performed, and the different antibody responses were analyzed by a discriminant analysis. This multivariate technique gave us, first, a selection of the most important responses against
Echinococcus granulosus
infection and, second, a procedure for the classification of patients into two groups: patients with hydatid disease and patients without a history of hydatid disease. This method was applied to 67 patients, 25 with active hydatid cysts (24 hepatic and 1 pulmonary) and 42 without a history of hydatid disease and was compared with the results obtained by conventional serology: indirect hemagglutination, latex particle agglutination, and basophil degranulation. An immunoelectrotransfer blot coupled to a discriminant analysis was more sensitive than conventional serological diagnosis and detected 100% of patients with an active hepatic hydatid cyst with a specificity of 100%. This method, however, failed to detect an uncomplicated hyaline pulmonary hydatid cyst.
Identification ofBartonella-Specific Immunodominant Antigens Recognized by the Feline Humoral Immune System
Authors: Freeland R. L. , Scholl D. T. , Rohde K. R. , Shelton L. J. , O’Reilly K. L.
Published: December 2019

The seroreactivities of both naturally and experimentally infected cats toBartonella henselaewas examined. Serum samples collected weekly from nine cats experimentally infected withB. henselaeLSU16 were tested by enzyme-linked immunosorbent assay (ELISA) and Western blot analysis. The magnitude and isotype of the antibody response were investigated by ELISA. Western blot analysis allowed the identification of at least 24Bartonella-specific antigens recognized by the cats during infection. Antibody titers to specific antigens, as determined by Western blot analysis, ranged from 10 to 640 and varied among the different antibody-antigen interactions. Absorption of sera from an experimentally infected cat, using whole cells and cell lysates of variousBartonellaspecies and other bacteria that commonly colonize cats, supported the identification of thoseBartonella-specific antigens recognized by the experimentally infected cats. Furthermore, a number of possible species- and type-specific antigens were identified. Finally, sera obtained from cats at local animal shelters were screened for the presence of antibodies directed against theBartonella-specific bands identified in the experimentally infected cats. A number ofBartonella-specific antigens have been identified to which strong antibody responses are generated in both experimentally and naturally infected cats, some of which may be useful in diagnosing species- and/or type-specific infections. In addition, the results from these experiments will lead to the development of monoclonal antibodies targeted against those genus-, species-, and type-specific antigens.
Immunoreactivity to Putative B-Cell Epitopes of Hepatitis G Virus Polyprotein in Viremic and Nonviremic Subjects
Authors: Toniutto Pierluigi , Fabris Carlo , Barbone Fabio , Tisminetzky Sergio G. , Liani Dario , Galai Tiziana , Barillari Giovanni , Biffoni Franco , Gasparini Vinicio , Pirisi Mario
Published: December 2019

The hepatitis G virus (HGV) polyprotein was scanned by computer-aided prediction of antigenicity to search for B-cell epitopes. Four polypeptide sequences, V37D (amino acids [aa] 1685 to 1721), V36S (aa 2102 to 2137), P37R (aa 2156 to 2192), and C40P (aa 2280 to 2319), were identified and synthesized for use in immunoassays. Antibodies to these peptides were searched for in a panel of 239 serum samples, which were also tested for anti-E2 antibodies and HGV RNA. Furthermore, the course of HGV markers was studied prospectively in four patients who had been transfused with HGV RNA-positive blood. There was a negative association between immunoreactivity to V37D and P37R and presence of HGV RNA (2 of 53 and 1 of 53, respectively;
P
< 0.05); none of the subjects with dual antibody positivity was HGV RNA positive. Anti-V37D and anti-P37R antibodies compared favorably with anti-E2 antibodies as markers of recovery from HGV infection. These results might be useful for the development of new, more sensitive diagnostic assays.
Cellular Immune Responses to ESAT-6 Discriminate between Patients with Pulmonary Disease Due toMycobacterium aviumComplex and Those with Pulmonary Disease Due toMycobacterium tuberculosis
Authors: Lein A. David , von Reyn C. Fordham , Ravn Pernille , Horsburgh C. Robert , Alexander Lorraine N. , Andersen Peter
Published: December 2019

ESAT-6 (for 6-kDa early secreted antigenic target) is a secreted antigen found almost exclusively in organisms of theMycobacterium tuberculosiscomplex. We compared in vitro gamma interferon (IFN-γ) responses by peripheral blood mononuclear cells to this antigen in patients with pulmonary disease due to eitherMycobacterium aviumcomplex (MAC) orMycobacterium tuberculosiswith those in healthy, skin test-negative, control subjects. Significant IFN-γ responses to ESAT-6 were detected in 16 (59%) of 27M. tuberculosispulmonary disease patients, 0 (0%) of 8 MAC disease patients, and 0 (0%) of 8 controls. Significant IFN-γ responses toM. tuberculosispurified protein derivative were detected in 23 (85%) of 27M. tuberculosisdisease patients, 2 (25%) of 8 MAC disease patients, and 5 (63%) of 8 healthy controls.M. aviumsensitin was recognized in 24 (89%) of 27M. tuberculosisdisease patients, 4 (50%) of 8 MAC disease patients, and 1 (13%) of 8 controls. IFN-γ responses to ESAT-6 are specific for disease due toM. tuberculosisand are not observed in patients with MAC disease or in healthy controls.
Serum Antibody Responses to
Helicobacter pylori
and the
cagA
Marker in Patients with Mucosa-Associated Lymphoid Tissue Lymphoma
Authors: Taupin Anne , Occhialini Alessandra , Ruskone-Fourmestraux Agnès , Delchier Jean-Charles , Rambaud Jean-Claude , Mégraud Francis
Published: December 2019

The lymphoma of the mucosa-associated lymphoid tissue (MALT) of the stomach has been linked to
Helicobacter pylori
infection, but the mechanisms involved in B-cell proliferation remain elusive. In a search for putative
H. pylori
-specific monoclonal immunoglobulin production, an
H. pylori
strain was isolated from 10 patients with MALT lymphoma and used to detect the specific serum antibody response to the homologous strain by immunoblotting. Moreover, the antigenicity of the different strains was compared by using each of the 10 sera. We found that the different strains induced highly variable patterns of systemic immunoglobulin G antibody response, although several bacterial antigens, such as the 60-kDa urease B, were often recognized by the different sera. The
cagA
marker was detected in the strains by PCR with specific primers and by dot blot analysis, and the CagA protein was found in the sera of 4 of the 10 patients by immunoblotting. In conclusion, MALT lymphoma patients, like other patients with
H. pylori
gastritis, exhibit a polymorphic systemic antibody response, despite an apparently similar antigenic profile. The CagA marker of pathogenicity is not associated with this disease.
Increased Levels of Alternatively Spliced Interleukin 4 (IL-4δ2) Transcripts in Peripheral Blood Mononuclear Cells from Patients with Systemic Sclerosis
Authors: Sakkas Lazaros I. , Tourtellotte Charles , Berney Steve , Myers Allen R. , Platsoucas Chris D.
Published: December 2019

Recent in vitro studies have shown that interleukin 4 (IL-4) induces and gamma interferon (IFN-γ) inhibits collagen production. To define the TH1(IFN-γ) and TH2(IL-4) cytokine profiles in systemic sclerosis (Sscl), a disease characterized by widespread fibrosis, we investigated IL-4 and IFN-γ transcripts in peripheral blood mononuclear cells and plasma protein levels in 13 patients with Sscl. Two previously identified IL-4 transcripts, a full-length transcript and an alternatively spliced (truncated) transcript (designated IL-4δ2), were identified in patients and normal controls. Significantly increased levels of total IL-4 transcripts (full-length plus IL-4δ2 transcripts) were found in patients with Sscl in comparison to those found in healthy controls (P= 0.003), and this increase was primarily due to an increase in the level of the alternatively spliced IL-4δ2 form. The IL-4δ2/full-length-IL-4 transcript ratio was significantly increased in Sscl patients (P< 0.0001, versus healthy controls). Sequencing analysis revealed that the frequency of IL-4 clones carrying the IL-4δ2 transcript was also substantially increased in patients with Sscl. Plasma IL-4 protein levels were increased in Sscl patients compared to those in healthy controls (P= 0.001) and correlated with total IL-4 transcript levels. The up-regulation of the fibrogenic IL-4 (a TH2 cytokine) in Sscl suggests a pathogenic role for IL-4 in this disease.
Comparison of PanBio Dengue Duo Enzyme-Linked Immunosorbent Assay (ELISA) and MRL Dengue Fever Virus Immunoglobulin M Capture ELISA for Diagnosis of Dengue Virus Infections in Southeast Asia
Authors: Cuzzubbo Andrea J. , Vaughn David W. , Nisalak Ananda , Solomon Tom , Kalayanarooj Siripen , Aaskov John , Dung Nguyen Minh , Devine Peter L.
Published: December 2019

The performances of the MRL dengue fever virus immunoglobulin M (IgM) capture enzyme-linked immunosorbent assay (ELISA) and the PanBio Dengue Duo IgM capture and IgG capture ELISA were compared. Eighty sera from patients with dengue virus infections, 24 sera from patients with Japanese encephalitis (JE), and 78 sera from patients with nonflavivirus infections, such as malaria, typhoid, leptospirosis, and scrub typhus, were used. The MRL test showed superior sensitivity for dengue virus infections (94 versus 89%), while the PanBio test showed superior specificity for JE (79 versus 25%) and other infections (100 versus 91%). The PanBio ELISA showed better overall performance, as assessed by the sum of sensitivity and specificity (
F
value). When dengue virus and nonflavivirus infections were compared,
F
values of 189 and 185 were obtained for the PanBio and MRL tests, respectively, while when dengue virus infections and JE were compared,
F
values of 168 and 119 were obtained. The results obtained with individual sera in the PanBio and MRL IgM ELISAs showed good correlation, but this analysis revealed that the cutoff value of the MRL test was set well below that of the PanBio test. Comparing the sensitivity and specificity of the tests at different cutoff values (receiver-operator analysis) revealed that the MRL and PanBio IgM ELISAs performed similarly in distinguishing dengue virus from nonflavivirus infections, although the PanBio IgM ELISA showed significantly better distinction between dengue virus infections and JE. The implications of these findings for the laboratory diagnosis of dengue are discussed.
Cloning and Expression of an Immunogenic Membrane-Associated Protein of
Helicobacter hepaticus
for Use in an Enzyme-Linked Immunosorbent Assay
Authors: Livingston Robert S. , Riley Lela K. , Hook Reuel R. , Besch-Williford Cynthia L. , Franklin Craig L.
Published: December 2019

Helicobacter hepaticus
is a bacterial pathogen that causes chronic active hepatitis and inflammatory bowel disease in mice. The purpose of this study was to develop a recombinant antigen-based enzyme-linked immunosorbent assay (ELISA) to detect
H. hepaticus
-infected mice. A genomic library of
H. hepaticus
was constructed and was screened with sera from
H. hepaticus
-infected mice. A 459-bp open reading frame that coded for an 18-kDa immunoreactive protein, MAP18, was identified. The gene had high identity with genes coding for outer membrane proteins of other bacteria, and the predicted amino acid sequence of MAP18 had a putative membrane-trafficking signal sequence and a putative signal peptidase II cleavage site. The recombinant protein was expressed in
Escherichia coli
as a glutathione
S
-transferase (GST) fusion protein, GST-MAP18, and purified by affinity chromatography. The 44-kDa fusion protein was detected on Western blots probed with sera from
H. hepaticus
-infected mice but was not detected on blots probed with sera from mice infected with
Helicobacter muridarum
or
Helicobacter bilis
or with sera from mice free of
Helicobacter
infection. The GST-MAP18 fusion protein was used as an antigen in an ELISA to detect anti-
H. hepaticus
antibodies in sera from infected mice. This ELISA was compared to an
H. hepaticus
-specific ELISA that uses a detergent extract of
H. hepaticus
as the antigen. Sera from mice naturally and experimentally infected with
H. hepaticus
,
H. bilis
, or
H. muridarum
and sera from mice free of
Helicobacter
infection were evaluated. Both ELISAs performed with a high specificity (98%); however, the detergent extract-based ELISA performed with a higher sensitivity (89%) than the recombinant protein-based ELISA (sensitivity, 66%). These data indicate that
H. hepaticus
carries a gene that encodes an immunogenic 18-kDa membrane-associated protein; however, antibodies to this protein are not detected in all infected mice.
Th1 Cytokine Patterns in Cervical Human Papillomavirus Infection
Authors: Scott Mark , Stites Daniel P. , Moscicki Anna-Barbara
Published: December 2019

The host’s immune response to cervical human papillomavirus (HPV) infection is poorly understood. In a longitudinal cohort of women with cervical HPV infections, defined by PCR-based HPV DNA testing, we used exfoliated cervical cells and reverse transcription-PCR to examine the cervical mucosal mRNA expression of cytokines involved in regulating cell-mediated immunity. We identified seven HPV-positive subjects who were found to have cleared their HPV infections 4 months later. In all seven, a T-helper type 1 (Th1) cytokine pattern (expression of gamma interferon and absence of interleukin-4) preceded clearance. The more variable cytokine patterns seen in HPV-negative subjects suggest that the Th1 pattern in the women with subsequent clearance was a response to the HPV infection. This contention is supported by additional cross-sectional data showing a Th1 pattern in a majority of HPV-positive women. This study establishes a feasible means for assessing local cytokine expression in the cervical milieu and demonstrates that a Th1 cytokine response is associated with subsequent clearance of cervical HPV infection.
Serological Evidence of Human Infection with the ProtozoanNeospora caninum
Authors: Tranas Jennifer , Heinzen Robert A. , Weiss Louis M. , McAllister Milton M.
Published: December 2019

Neospora caninumis a protozoan parasite that is closely related toToxoplasma gondii. Dogs are a definitive host. Prior to its discovery in 1988,N. caninuminfection in animals was often mistakenly diagnosed as toxoplasmosis. Neosporosis in animals is characterized by encephalitis, abortion, and other conditions that clinically and pathologically resemble toxoplasmosis. The potential ofN. caninumto infect humans is unknown. Therefore, evidence of human exposure to this parasite was sought by screening for antibodies in blood donors by indirect fluorescent antibody (IFA) tests and immunoblotting. Of 1,029 samples screened, 69 (6.7%) had titers of 1:100 by IFA testing. Fifty of the 69 (72%) sera that were positive forN. caninumwere also negative for a closely related protozoan pathogen of humans,T. gondii. Immunoblot analysis confirmed the specificity of the positive sera forN. caninumantigens, with several sera recognizing multipleNeosporaantigens with molecular masses similar to those of antigens recognized by monkey anti-N. caninumserum. An immunodominant antigen of approximately 35 kDa was observed with 12 sera. These data provide evidence of human exposure toN. caninum, although the antibody titers in healthy donors were low. The significance of human exposure to, and possible infection with, this parasite is unknown and warrants further study.
Effects of Orally Administered Viable
Lactobacillus rhamnosus
GG and
Propionibacterium freudenreichii
subsp.
shermanii
JS on Mouse Lymphocyte Proliferation
Authors: Kirjavainen Pirkka V. , ElNezami Hani S. , Salminen Seppo J. , Ahokas Jorma T. , Wright Paul F. A.
Published: December 2019

Immunomodulation by probiotics is a subject of growing interest, but the knowledge of dose response and time profile relationships is minimal. In this study we examined the effects of
Lactobacillus rhamnosus
GG (LGG) and
Propionibacterium freudenreichii
subsp.
shermanii
JS (PJS) on the proliferative activity of murine lymphocytes ex vivo. Dose dependency was assessed by treating animals perorally with a low or a high dose (i.e., 10
9
or 10
12
viable bacteria/kg of body weight) for 7 days. The lower dose levels of each strain appeared to enhance T-cell proliferation at the optimal concanavalin A (ConA) concentration (by 69 to 84%) and B-cell proliferation at the optimal and supraoptimal concentrations of lipopolysaccharide (by 57 to 82%). B-cell proliferation was also enhanced by the high LGG dose (by 32 to 39%) but was accompanied by a marginal decrease in T-cell proliferation (by 8%) at the optimal ConA concentration. The time profiles of the immune responses were assessed after daily treatment with the higher dose for 3, 7, and 14 days. A significant decrease in basal lymphoproliferation (by 32 to 42%) was observed with PJS treatment after the 3- and 7-day periods; however, this activity returned to control levels after 14 days of treatment, which also resulted in significantly enhanced T-cell proliferation at optimal and supraoptimal ConA concentrations (by 24 to 80%). The 14-day LGG treatment also enhanced the latter activity (by 119%). In conclusion, LGG and PJS have specific dose- and duration-dependent immunomodulatory effects on the proliferative activity of B and T lymphocytes and may also reduce lymphocyte sensitivity to the cytotoxic effects of lectin mitogens.
Lipopolysaccharide- and Cholera Toxin-Specific Subclass Distribution of B-Cell Responses in Cholera
Authors: Qadri Firdausi , Ahmed Firoz , Karim M. Manjurul , Wenneras Christine , Begum Yasmin Ara , Salam Mohammad Abdus , Albert M. John , McGhee Jerry R.
Published: December 2019

The immunoglobulin subclass responses to homologous lipopolysaccharide (LPS) and to cholera toxin (CT) in adult patients infected withVibrio choleraeO1 andV. choleraeO139 were studied. LPS-specific antibody-secreting cells (ASC) of both the immunoglobulin A1 (IgA1) and IgA2 subclasses were seen, with the IgA1 ASC response predominating in bothV. choleraeO1- and O139-infected patients. For antibodies in plasma, by day 11 after onset of disease, allV. choleraeO1- infected patients responded to homologous LPS with the IgA1 subclass (P= 0.001), whereas fewer (68%) responded with the IgA2 subclass (P= 0.007). About 89% ofV. choleraeO139-infected patients responded with the IgA1 subclass (P= 0.003), and only 21% responded with the IgA2 subclass (not significant [NS]). Both groups of cholera patients showed significant increases in LPS-specific IgG1, IgG2, and IgG3 antibodies in plasma. In feces, the response to homologous LPS occurred in both groups of patients with the IgA1 and IgA2 subclasses, with 55 to 67% of patients showing a positive response.V. choleraeO1- and O139-infected patients showed CT-specific ASC responses of the different IgG and IgA subclasses in the circulation, and the pattern followed the order IgG1 > IgA1 > IgG2 > IgA2, with low levels of IgG3 and IgG4 ASC. Plasma anti-CT antibody responses in all subclasses were seen by day 11 after onset of disease. Although there were no increases in CT-specific ASC of the IgG3 (NS) and IgG4 (NS) subtypes, there were significant increases of these two subclasses in plasma (P≤ 0.001). The response to CT in the fecal extracts was contributed to by both IgA1 and IgA2 isotypes, with 67 to 75% of the patients responding. Thus, the mucosa-derived ASC and fecal antibodies to LPS and CT were of both the IgA1 and IgA2 subclasses; in plasma, the contribution from IgA2 was lower. Very little difference in the B-cell responses to LPS and CT in the different subclasses was seen in the two groups of cholera patients. Vaccines against O1 and O139 cholera ideally should stimulate antibody subclasses that are likely to offer protection.
Changes in Endotoxin-Binding Proteins during Major Elective Surgery: Important Role for Soluble CD14 in Regulation of Biological Activity of Systemic Endotoxin
Authors: Hiki Naoki , Berger Dieter , Dentener Mieke A. , Mimura Yoshikazu , Buurman Wim A. , Prigl Claus , Seidelmann Manuela , Tsuji Eiichi , Kaminishi Michio , Beger Hans G.
Published: December 2019

Assessment of circulating endotoxin during the perioperative period, which is only demonstrated by theLimulusamebocyte lysate (LAL) test, may be modulated by several endotoxin-binding proteins. Endotoxin-neutralizing capacity (ENC) and the plasma levels of soluble CD14 (sCD14), lipopolysaccharide-binding protein, and bactericidal/permeability-increasing protein (BPI) were determined in 40 patients 6 h prior to skin incision for major abdominal surgery. The bioactivity of plasma endotoxin was tested by the polymyxin B-inhibited stimulatory activity of the plasma samples on healthy monocytes as measured by the release of tumor necrosis factor alpha. Plasma endotoxin levels in almost all patients increased from 0.05 ± 0.01 to 0.23 ± 0.03 experimental units (EU) per ml (P< 0.001); more specifically, 17 of 40 samples showed endotoxin levels of greater than 0.2 EU per ml and corresponding reductions in ENC. Soluble CD14 plasma levels were decreased from 5.6 ± 0.3 to 4.6 ± 0.3 μg per ml (P< 0.05). ENC was strongly correlated with the sCD14 plasma concentration throughout the period of observation. The addition of sCD14-neutralizing monoclonal anti-sCD14 antibodies reduced ENC both pre- and postoperatively. No correlation could be established between ENC and the plasma levels of BPI, high-density lipoproteins, or low-density lipoproteins determined by measuring the concentrations of apoprotein A and apoprotein B. Biologically active endotoxin was found in only 6 of 17 samples with endotoxin levels greater than 0.2 EU per ml in the LAL test. These samples could be characterized by their perioperative loss of at least 35% of their sCD14. No change in sCD14 was detected in the remaining 11 samples. The perioperative loss of ENC is partly caused by the loss of sCD14 resulting from its consumption by endotoxin reaching the bloodstream. This study demonstrated the role of sCD14 on the bioactivity of circulating endotoxin in a human model of endotoxemia after major abdominal surgery.
Identification of a Subset of Common Variable Immunodeficiency Patients with Impaired B-Cell Protein Tyrosine Phosphorylation
Authors: Schwartz Rivka , Porat Yael Ben-Anat , Handzel Zeev , Sthoeger Zeev , Garty Ben-Zion , Confino-Cohen Ronit , Levy Jacov , Zan-Bar Israel
Published: December 2019

The mechanisms responsible for common variable immunodeficiency syndrome (CVID) are as yet unknown. In the present study, we show that the B-cell dysfunction in a subset of CVID patients is caused by defective protein tyrosine phosphorylation (PTP). We demonstrated that the PTP level and immunoglobulin (Ig) secretion malfunctions can be successfully repaired when normal plasma membrane components are implanted into these patients’ B cells. Stimulation of CVID patients’ peripheral blood mononucleated cells with anti-Ig antibody revealed that 7 of 11 patients had lower PTP levels than those found in the normal donor cells. Plasma membrane implantation to the cells of these patients resulted in elevated PTP levels which reached normal levels upon stimulation with anti-human Ig antibody. The results revealed two distinct groups of CVID patients. The first group included patients whose B cells expressed low PTP levels after Ig stimulation. In these patients the plasma membrane implantation restored the normal PTP level as well as the ability to secrete IgM and/or IgG after B-cell stimulation. In the second group, patients whose B cells expressed a normal PTP level after Ig stimulation, with no restoration of their ability to secrete Ig upon plasma membrane implantation and lipopolysaccharide stimulation. We conclude that the first group has an early signal transduction defect located in the B-cell plasma membrane, while in the second group the defect is located elsewhere.
Sterols of
Pneumocystis carinii hominis
Organisms Isolated from Human Lungs
Authors: Kaneshiro Edna S. , Amit Zunika , Chandra Jyotsna , Baughman Robert P. , Contini Carlo , Lundgren Bettina
Published: December 2019

The opportunistic pathogen
Pneumocystis carinii
causes pneumonia (
P. carinii
pneumonia, or PCP) in immunocompromised individuals such as AIDS patients. Rat-derived
P. carinii carinii
organisms have distinct sterols which are not synthesized by mammals and not found in other microbes infecting mammalian lungs. The dominant sterol present in the organism is cholesterol (which is believed to be scavenged from the host), but other sterols in
P. carinii carinii
have an alkyl group at C-24 of the sterol side chain (C
28
and C
29
24-alkylsterols) and a double bond at C-7 of the nucleus. Recently, pneumocysterol (C
32
), which is essentially lanosterol with a C-24 ethylidene group, was detected in lipids extracted from a formalin-fixed human
P. carinii
-infected lung, and its structures were elucidated by gas-liquid chromatography, mass spectrometry, and nuclear magnetic resonance spectrometry in conjunction with analyses of chemically synthesized authentic standards. The sterol composition of isolated
P. carinii hominis
organisms has yet to be reported. If
P. carinii
from animal models is to be used for identifying potential drug targets and for developing chemotherapeutic approaches to clear human infections, it is important to determine whether the 24-alkylsterols of organisms found in rats are also present in organisms in humans. In the present study, sterol analyses of
P. carinii hominis
organisms isolated from cryopreserved human
P. carinii
-infected lungs and from bronchoalveolar lavage fluid were performed. Several of the same distinct sterols (e.g., fungisterol and methylcholest-7-ene-3β-ol) previously identified in
P. carinii carinii
were also present in organisms isolated from human specimens. Pneumocysterol was detected in only some of the samples.
The Glutamate-Rich Protein (GLURP) ofPlasmodium falciparumIs a Target for Antibody-Dependent Monocyte-Mediated Inhibition of Parasite Growth In Vitro
Authors: Theisen Michael , Soe Soe , Oeuvray Claude , Thomas Alan W. , Vuust Jens , Danielsen Steffen , Jepsen Søren , Druilhe Pierre
Published: December 2019

Monocyte-dependent as well as direct inhibitory effects of antimalarial antibodies point toward antigens accessible at the time of merozoite release as targets for biologically active antibodies capable of mediating protection againstPlasmodium falciparum. The glutamate-rich protein (GLURP), being an antigen associated with mature schizont-infected erythrocytes, was therefore the object of the present investigation, in which we analyzed whether anti-GLURP antibodies can either interfere directly with merozoite invasion or act indirectly by promoting a monocyte-dependent growth inhibition, antibody-dependent cellular inhibition. GLURP-specific human immunoglobulin G (IgG) antibodies, from pooled IgG of healthy Liberian adults who were clinically immune to malaria, were purified by affinity chromatography on columns containing R0 (N-terminal nonrepetitive region of GLURP) or R2 (C-terminal repetitive region of GLURP) recombinant protein or synthetic peptides as ligands. Analysis of the pattern of reactivity of highly purified anti-GLURP antibodies led to the definition of at least four B-cell epitopes. One epitope was specific for R0, two were specific for R2, and the fourth displayed cross-reactivity between R0 and R2. None of the purified IgG antibodies had direct invasion-inhibitory effects, even at high concentrations. In contrast, when allowed to cooperate with monocytes, all anti-GLURP IgG preparations mediated a strong monocyte-dependent parasite growth inhibition in a dose-dependent manner.
Binding of Salivary Glycoprotein-Secretory Immunoglobulin A Complex to the Surface Protein Antigen of
Streptococcus mutans
Authors: Oho Takahiko , Yu Hao , Yamashita Yoshihisa , Koga Toshihiko
Published: December 2019

The interaction between a surface protein antigen (PAc) of
Streptococcus mutans
and human salivary agglutinin was analyzed with a surface plasmon resonance biosensor. The major component sugars of the salivary agglutinin were galactose, fucose, mannose,
N
-acetylglucosamine,
N
-acetylgalactosamine, and
N
-acetylneuraminic acid. Binding of salivary agglutinin to PAc was calcium dependent and heat labile and required a pH greater than 5. Binding was significantly inhibited by
N
-acetylneuraminic acid and α2,6-linked sialic acid-specific lectin derived from
Sambucus sieboldiana
in a dose-dependent manner. Pretreatment of the salivary agglutinin with sialidase reduced the binding activity of the agglutinin to the PAc molecule. The agglutinin was dissociated into high-molecular-mass glycoprotein and secretory immunoglobulin A (sIgA) components by electrophoretic fractionation in the presence of 1% sodium dodecyl sulfate and 1% 2-mercaptoethanol. Neither of the components separated by electrophoretic fractionation, high-molecular-mass glycoprotein or sIgA, bound to the PAc molecule. Furthermore, the high-molecular-mass glycoprotein strongly inhibited the binding of the native salivary complex to PAc. These results suggest that the complex formed by the high-molecular-mass salivary glycoprotein and sIgA is essential for the binding reaction and that the sialic acid residues of the complex play an important role in the interaction between the agglutinin and PAc of
S. mutans.