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See detailRecombinant gp350 vaccine for infectious mononucleosis: A phase 2, randomized, double-blind, placebo-controlled trial to evaluate the safety, immunogenicity, and efficacy of an Epstein-Barr virus vaccine in healthy young adults
Sokal, E. M.; Hoppenbrouwers, K.; Vandermeulen, C. et al

in Journal of Infectious Diseases (2007), 196(12), 1749-1753

Background. To date, there is no commercially available vaccine to prevent infectious mononucleosis, a disease frequently induced by Epstein-Barr virus (EBV) infection in adolescents or adults devoid of ... [more ▼]

Background. To date, there is no commercially available vaccine to prevent infectious mononucleosis, a disease frequently induced by Epstein-Barr virus (EBV) infection in adolescents or adults devoid of preexisting immunity to the virus. Methods. A total of 181 EBV-seronegative, healthy, young adult volunteers were randomized in a double-blind fashion to receive either placebo or a recombinant EBV subunit glycoprotein 350 (gp350)/aluminum hydroxide and 3-O-desacyl-4'-monophosphoryl lipid A (AS04) candidate vaccine in a 3-dose regimen. Results. The vaccine had demonstrable efficacy (mean efficacy rate, 78.0% [95% confidence interval {CI}, 1.0% -96.0%]) in preventing the development of infectious mononucleosis induced by EBV infection, but it had no efficacy in preventing asymptomatic EBV infection. One month after receipt of the final dose of gp350 vaccine, 98.7% of subjects showed seroconversion to anti-gp350 antibodies (95% CI, 85.5%-97.9%), and they remained anti-gp350 antibody positive for > 18 months. Furthermore, there were no concerns regarding the safety or reactogenicity of the gp350/AS04 vaccine. Conclusion. These data support the clinical feasibility of using an EBV vaccine to prevent infectious mononucleosis. [less ▲]

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See detailPhase I/II studies to evaluate safety and immunogenicity of a recombinant gp350 Epstein-Barr virus vaccine in healthy adults
Moutschen, Michel ULg; Leonard, Philippe ULg; Sokal, E. M. et al

in Vaccine (2007), 25(24), 4697-4705

Two double-blind randomised controlled studies (phase I and I/II) were performed to assess for the first time the safety and immunogenicity of a recombinant subunit gp350 Epstein-Barr virus (EBV) vaccine ... [more ▼]

Two double-blind randomised controlled studies (phase I and I/II) were performed to assess for the first time the safety and immunogenicity of a recombinant subunit gp350 Epstein-Barr virus (EBV) vaccine in 148 healthy adult volunteers. All candidate vaccine formulations had a good safety profile and were well tolerated, with the incidence of solicited and unsolicited symptoms within a clinically acceptable range. One serious adverse event was reported in the phase I trial which was considered to be of suspected relationship to vaccination. The gp350 vaccine formulations were immunogenic and induced gp350-specific antibody responses (including neutralising antibodies). (c) 2007 Elsevier Ltd. All rights reserved. [less ▲]

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See detailEffect of elevated PCO2 on optical properties of the coccolithophorid Emiliania huxleyi grown under nitrate limitation
Denis, M.; Sciandra; Harlay, Jérôme ULg et al

in Cytometry. Part A : The Journal of the International Society for Analytical Cytology (2004), 59A(1), 105

Side scatter and red fluorescence properties of the coccolithophore Emiliania huxleyi were investigated by flow cytometry when NO3-limited continuous cultures were submitted to a CO2 partial pressure ... [more ▼]

Side scatter and red fluorescence properties of the coccolithophore Emiliania huxleyi were investigated by flow cytometry when NO3-limited continuous cultures were submitted to a CO2 partial pressure (pCO2) increase from 400 to 700 ppm. Cultures renewed at the rate of 0.5 d-1 and were submitted to saturating light level. pCO2 was controlled by bubbling CO2-rich or CO2- free air in the cultures. Most of the analyses were repeated 5 times and the average SD were < 1.6%, 0.1 and 0.2% for counting, fluorescence and side scatter respectively. Considering the possible decalcification induced by the increase of CO2 in the chemostat atmosphere, the maximum variation that can be expected for side scatter is that provided by the coccolith depletion upon acidification of the cell suspension. The acidification induced a large (36%) decrease of the side scatter signal but had no detectable effect on the red fluorescence. A control was run with a non-calcifying species, Dunaliella tertiolecta, where acidification induced no detectable change, both on fluorescence and side scatter. During the time of the experiment, the decline of side scatter in chemostat 1 never approached the potential 36% change observed when coccoliths are fully dissolved. Interestingly, the specific chl a fluorescence of E. huxleyi slightly increased during the period of high CO2 level. At the end of the experiment this increase amounted to a significant 2.8% of the initial signal. Furthermore, it progressed linearly with time over the period of observation. However, the experiment did not last enough to know if the fluorescence increase had already reached its maximum value. The acidification experiment supported the use of side scatter as a relevant parameter to trace potential changes in calcification. Since the estimated 25% decrease in calcification induced by the rise in CO2 atmosphere did not result in dramatic changes in side scatter values, we can conclude that the number of cocoliths and the overall shape and granulosity of cells was not significantly affected by this decrease. Changes must have only affected tiny structure details of the coccoliths which is supported by scanning electron microscopy observations. The small but significant increase of the fluorescence signal can be considered as a physiological response to the CO2 rise. This suggests a more dynamic photosynthetic process that would result in a higher rate of organic matter production providing that the system is not nutrient limited as in the present situation. [less ▲]

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See detailChoice of an adjuvant for vaccination trials
Vermout, Sandy; Denis, M.; Losson, Bertrand ULg et al

in Annales de Médecine Vétérinaire (2003), 147(6), 393-401

The development of new vaccines, containing protective antigens that are more and more well characterized, is hindered by the lack of adjuvants able both to amplify immune response and to control it ... [more ▼]

The development of new vaccines, containing protective antigens that are more and more well characterized, is hindered by the lack of adjuvants able both to amplify immune response and to control it qualitatively. A number of tumors and infectious diseases could be treated with adjuvant preparations that would adequately intensify and modulate specific immune response; in particular, the possibility to specifically induce a Th1 response seems to be of paramount importance for the prevention and for the cure of these diseases. Furthermore, these adjuvants must be as safe as possible, not only for commercial applications, but also in the respect of laboratory animals' welfare. This review describes the different adjuvants presently used in vaccinology, classifying them following their chemical nature and presenting for each category the knowledge concerning their activity and toxicity. [less ▲]

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See detailMesoscale surface distribution of biogeochemical characteristics in the Crozet Basin frontal zones (South Indian Ocean)
Fiala, M.; Delille, Bruno ULg; Dubreuil, C. et al

in Marine Ecology. Progress Series (2003), 249

A mesoscale study was conducted in January and February 1999 in the Crozet Basin frontal zones (43degrees50' to 45degrees20'S, 61degrees00' to 64degrees30'E) within the southernmost and easternmost ... [more ▼]

A mesoscale study was conducted in January and February 1999 in the Crozet Basin frontal zones (43degrees50' to 45degrees20'S, 61degrees00' to 64degrees30'E) within the southernmost and easternmost convergence area of the Antarctic Circumpolar Current (ACC) and the Agulhas Return Current (ARC). Distribution of biogeochemical parameters was strongly linked to the merged Subtropical (STF) and Subantarctic (SAF) Fronts which mark the border between the cold and less saline subantarctic waters and the warm and more saline subtropical waters. This survey took place during a post-bloom period. Chlorophyll a concentrations were low throughout the study area ranging from 0.2 mug l(-1) in the Polar Frontal Zone (PFZ) to 0.4 mug l(-1) in the Subtropical Zone (STZ). Maximum chlorophyll a values (0.8 mug l(-1)) associated with an increase in biogenic silica concentration (from 0.03 to 0.34 muM) and a diatom peak (1.2 x 10(5) cells l(-1)) were encountered in the northeastern part of the STF edge. Despite northwardly decreasing concentrations of nitrates from 14 muM in the PFZ to 6 PM in the STZ, they were not the main factor limiting phytoplankton growth. Low silicic acid (mean = 0.6 muM) could have limited diatom development in the PFZ and the STZ where diatom numbers were low. In STZ waters, where average diatom numbers were highest, various species of Nitzschia and Thalassiothrix were common, but Pseudonitzschia spp. were dominant. Throughout the survey area, pico- and nano-sized cells dominated the phytoplankton assemblage, and their number was the highest in the STZ. Cyanobacteria, only present in subtropical waters >12.5degreesC, were the major component of the picoplankton size-fraction. While dinoflagellate numbers were low in the Subantarctic Zone (SAZ), their abundance and species numbers increased in the STZ, where Oxytoxum laticeps became dominant and several further large-size species of Prorocentrum, Ceratium and Gymnodinium appeared in addition to those at the STF. The distribution of different biogeochemical parameters suggests that the Crozet Basin frontal region is a non-exporting system at the end of summer. During this post-bloom period, biological activity is low and phytoplankton growth severely limited. This is evidenced by the weak dependence of the partial pressure of carbon dioxide (pCO(2)) on biological activity and the importance of the air-sea exchange in maintaining pCO(2) close to saturation. [less ▲]

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See detailResponse of coccolithophorid Emiliania huxleyi to elevated partial pressure of CO2 under nitrogen limitation
Sciandra, A.; Harlay, Jérôme ULg; Lefevre, D. et al

in Marine Ecology. Progress Series (2003), 261

Precipitation of calcium carbonate by phytoplankton in the photic oceanic layer is an important process regulating the carbon cycling and the exchange Of CO2 at the ocean-atmosphere interface. Previous ... [more ▼]

Precipitation of calcium carbonate by phytoplankton in the photic oceanic layer is an important process regulating the carbon cycling and the exchange Of CO2 at the ocean-atmosphere interface. Previous experiments have demonstrated that, under nutrient-sufficient conditions, doubling the partial pressure Of CO2 (pCO(2)) in seawater-a likely scenario for the end of the century-can significantly decrease both the rate of calcification by coccolithophorids and the ratio of inorganic to organic carbon production. The present work investigates the effects of high pCO(2) on calcification by the coccolithophore Emiliania huxleyi (Strain TW1) grown under nitrogen-limiting conditions, a situation that can also prevail in the ocean. Nitrogen limitation was achieved in NO3-limited continuous cultures renewed at the rate of 0.5 d(-1) and exposed to a saturating light level. pCO(2) was increased from 400 to 700 ppm and controlled by bubbling CO2-rich or CO2-free air into the cultures. The pCO(2) shift has a rapid effect on cell physiology that occurs within 2 cell divisions subsequent to the perturbation. Net calcification rate (C) decreased by 25% and, in contrast to previous studies with N-replete cultures, gross community production (GCP) and dark community respiration (DCR) also decreased. These results suggest that increasing pCO(2) has no noticeable effect on the calcification/photosynthesis ratio (C/P) when cells of E. huxleyi are NO3-limited. [less ▲]

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See detailHumoral and Cell-Mediated Immune Responses of Beef and Dairy Cattle Experimentally Infested with Psoroptes Ovis
Lonneux, J. F.; Nguyen, T. Q.; Hollanders, W. et al

in American Journal of Veterinary Research (1998), 59(5), 583-7

OBJECTIVE: To compare cellular and humoral immune responses of beef (Belgian White and Blue [BWB]) and dairy (Friesian-Holstein [FH]) cattle to Psoroptes ovis infestation and to determine whether P ovis ... [more ▼]

OBJECTIVE: To compare cellular and humoral immune responses of beef (Belgian White and Blue [BWB]) and dairy (Friesian-Holstein [FH]) cattle to Psoroptes ovis infestation and to determine whether P ovis infestation impaired immune responses to infectious bovine rhinotracheitis virus (IBR) vaccine or an immunogenic protein (keyhole-limpet hemocyanin [KLH]). ANIMALS: 19 BWB and 6 FH 1-year-old calves. PROCEDURE: 2 trials were performed. In each trial, 7 (trial 1) or 6 (trial 2) BWB calves and 3 FH calves were experimentally infested with P ovis and 3 BWB calves were maintained as uninfested controls. Animals were inoculated with KLH and IBR virus vaccine twice; 3 BWB calves in each trial were treated with ivermectin. Serum antibody responses to KLH, IBR virus, and P ovis were measured by use of ELISA. A lymphocyte transformation assay was used to determine nonspecific responses to 3 mitogens and specific lymphocyte reactivity to P ovis antigen. RESULTS: In each trial, 3 BWB and 3 FH calves developed clinical signs of psoroptic mange and mites could be recovered. Infested and control animals developed similar antibody titers to KLH and IBR virus. Antibodies to P ovis were detected early in some infested calves, and this was correlated with a marked cell-mediated immune response. Lymphocyte responsiveness to the 3 mitogens was not significantly different among groups. CONCLUSIONS: In these calves, infestation with P ovis induced a marked humoral and cell-mediated immune response. Immunosuppression was not evident. [less ▲]

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See detailOptimization of murine CD8+ cytotoxic T-lymphocyte responses to pseudorabies virus
Depierreux, C.; Graff, I.; Lancelot, V. et al

in Journal of Immunological Methods (1997), 203

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See detailThe Role of Glycoproteins gC, gE, gI and gG in the Induction of Cell-Mediated Immune Responses to Bovine Herpesvirus 1
Denis, M.; Hanon, E.; Rijsewijk, F. A. et al

in Veterinary Microbiology (1996), 53(1-2), 121-32

Mutant viruses with deletions in genes encoding non-essential glycoproteins are considered as promising bovine herpesvirus 1 (BHV1) vaccine candidates. The present study compared the influence of various ... [more ▼]

Mutant viruses with deletions in genes encoding non-essential glycoproteins are considered as promising bovine herpesvirus 1 (BHV1) vaccine candidates. The present study compared the influence of various gene deletions (gC, gE, gI, gG) on the induction of cell-mediated immune responses against the virus. The highest BHV1 specific lymphoproliferative response was observed in the group of calves inoculated with the gC- mutant. However, in all groups of inoculated calves, limiting dilution analysis showed marked individual variability in the number of BHV1 specific T lymphocytes that were stimulated. The same animals were then challenged with wild-type BHV1. In these animals, limiting dilution analysis did not reveal gE, gI nor gG as a major T lymphocyte antigen. However, further analysis suggested the T cell antigenicity of gE in a low number of BHV1 hyperimmunized calves. Stimulation of MHC unrestricted cytotoxicity was also evaluated after inoculation with the various deletion mutants. Cytotoxicity in gC- inoculated calves was as high as in BHV1 inoculated calves. In conclusion, among the BHV1 deletion mutants that were tested, the gC- mutant stimulated the best cell-mediated immune responses. [less ▲]

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See detailInactivated Bovine Herpesvirus 1 Induces Apoptotic Cell Death of Mitogen-Stimulated Bovine Peripheral Blood Mononuclear Cells
Hanon, E.; Vanderplasschen, Alain ULg; Lyaku, S. et al

in Journal of Virology (1996), 70(6), 4116-4120

Bovine herpesvirus 1 (BHV-1) is able to inhibit the proliferation of bovine peripheral blood mononuclear cells. Here, we have demonstrated that live BHV-1 and, interestingly, inactivated BHV-1 can induce ... [more ▼]

Bovine herpesvirus 1 (BHV-1) is able to inhibit the proliferation of bovine peripheral blood mononuclear cells. Here, we have demonstrated that live BHV-1 and, interestingly, inactivated BHV-1 can induce apoptosis of mitogen-stimulated bovine peripheral blood mononuclear cells in vitro. [less ▲]

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See detailQuantitative Assessment of the Specific Cd4+ T Lymphocyte Proliferative Response in Bovine Herpesvirus 1 Immune Cattle
Denis, M.; Kaashoek, M. J.; van Oirschot, J. T. et al

in Veterinary Immunology and Immunopathology (1994), 42(3-4), 275-86

We quantified the CD4+ T cell proliferation specific for bovine herpesvirus 1 (BHV-1) in peripheral blood mononuclear cells from cattle. The stimulation index as detected in proliferative assays performed ... [more ▼]

We quantified the CD4+ T cell proliferation specific for bovine herpesvirus 1 (BHV-1) in peripheral blood mononuclear cells from cattle. The stimulation index as detected in proliferative assays performed in the presence of BHV-1 antigen is highly variable in immune cattle. By using proliferative assays performed after negative selection we showed that, as expected, CD4+ T cells were the limiting cell type for antigen-induced proliferation. Neither B, gamma delta T nor CD8+ cells seemed to be involved. The limiting dilution method was established to obtain quantitative estimations, namely frequencies of specific T cells. When limiting dilution cultures were supplemented with interleukin-2 (IL-2), an IL-2 induced unspecific cell proliferation masked the specific T cell proliferation. Natural killer cells were not the major cell type involved, but CD4+ lymphocytes themselves seemed to respond to IL-2 irrespective of the presence of antigen. When cultures were performed without addition of IL-2, the frequency of BHV-1 specific proliferative T cells could be obtained by the difference between the frequency of proliferating cells calculated in the presence and absence of antigen. The method provides a sensitive and quantitative means to measure the T cell immune response to BHV-1 vaccine candidates. [less ▲]

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See detailIdentification of Different Target Glycoproteins for Bovine Herpes Virus Type 1-Specific Cytotoxic T Lymphocytes Depending on the Method of in Vitro Stimulation
Denis, M.; Slaoui, M.; Keil, G. et al

in Immunology (1993), 78(1), 7-13

Vaccinia virus recombinants expressing the three major bovine herpes virus-1 (BHV-1) glycoproteins gI, gIII and gIV were used to identify the major target antigens for BHV-1-specific CTL isolated from ... [more ▼]

Vaccinia virus recombinants expressing the three major bovine herpes virus-1 (BHV-1) glycoproteins gI, gIII and gIV were used to identify the major target antigens for BHV-1-specific CTL isolated from immune cattle. Peripheral blood mononuclear cells (PBMC) expanded in vitro in the presence of interleukin-2 (IL-2) and lysed both gIII- and gIV-infected target cells. Secondary in vitro stimulation of PBMC was also performed in the presence of either fixed BHV-1-infected autologous fibroblasts or ultraviolet (UV)-inactivated virus. Both methods of antigen presentation allowed the proliferation of BHV-1-specific CTL but the target glycoprotein for these CTL differed depending on the method of stimulation. Vaccinia-gIV-infected targets were lysed predominantly when PBMC were stimulated by fixed infected fibroblasts, whilst PBMC stimulated by UV-inactivated virus lysed mostly vaccinia-gIII-infected targets. This observation could be explained by a different processing pathway of BHV-1 antigens in each cell type involved. [less ▲]

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See detailImpact des biotechnologies en santé animale
Pastoret, Paul-Pierre ULg; Thiry, Etienne ULg; Brochier, B. et al

Report (1990)

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