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2.
Mucosal Immunol ; 11(3): 979-993, 2018 05.
Article de Anglais | MEDLINE | ID: mdl-28930286

RÉSUMÉ

Mucosal immunity is often required for protection against respiratory pathogens but the underlying cellular and molecular mechanisms of induction remain poorly understood. Here, systems vaccinology was used to identify immune signatures after pulmonary or subcutaneous immunization of mice with pertussis outer membrane vesicles. Pulmonary immunization led to improved protection, exclusively induced mucosal immunoglobulin A (IgA) and T helper type 17 (Th17) responses, and in addition evoked elevated systemic immunoglobulin G (IgG) antibody levels, IgG-producing plasma cells, memory B cells, and Th17 cells. These adaptive responses were preceded by unique local expression of genes of the innate immune response related to Th17 (e.g., Rorc) and IgA responses (e.g., Pigr) in addition to local and systemic secretion of Th1/Th17-promoting cytokines. This comprehensive systems approach identifies the effect of the administration route on the development of mucosal immunity, its importance in protection against Bordetella pertussis, and reveals potential molecular correlates of vaccine immunity to this reemerging pathogen.


Sujet(s)
Protéines de la membrane externe bactérienne/immunologie , Vaccin anticoquelucheux/immunologie , Lymphocytes auxiliaires Th1/immunologie , Cellules Th17/immunologie , Coqueluche/immunologie , Animaux , Bordetella pertussis , Cytokines/métabolisme , Vésicules cytoplasmiques , Immunité cellulaire , Immunité muqueuse , Immunisation , Immunoglobuline A/sang , Activation des lymphocytes , Souris , Membre-3 du groupe F de la sous-famille-1 de récepteurs nucléaires/génétique , Membre-3 du groupe F de la sous-famille-1 de récepteurs nucléaires/métabolisme , Récepteurs de surface cellulaire/génétique , Récepteurs de surface cellulaire/métabolisme , Transcriptome
3.
Pharm Res ; 26(7): 1635-43, 2009 Jul.
Article de Anglais | MEDLINE | ID: mdl-19326190

RÉSUMÉ

PURPOSE: In this study, modulation of the immune response against diphtheria toxoid (DT) by various adjuvants in transcutaneous immunization (TCI) with microneedle array pretreatment was investigated. METHODS: TCI was performed on BALB/c mice with or without microneedle array pretreatment using DT as a model antigen co-administrated with lipopolysaccharide (LPS), Quil A, CpG oligo deoxynucleotide (CpG) or cholera toxin (CT) as adjuvant. The immunogenicity was evaluated by measuring serum IgG subtype titers and neutralizing antibody titers. RESULTS: TCI with microneedle array pretreatment resulted in a 1,000-fold increase of DT-specific serum IgG levels as compared to TCI. The immune response was further improved by co-administration of adjuvants, showing a progressive increase in serum IgG titers when adjuvanted with LPS, Quil A, CpG and CT. IgG titers of the CT-adjuvanted group reached levels comparable to those obtained after DT-alum subcutaneous injection. The IgG1/IgG2a ratio of DT-specific antibodies decreased in the following sequence: plain DT, Quil A, CT and CpG, suggesting that the immune response was skewed towards the Th1 direction. CONCLUSIONS: The potency and the quality of the immune response against DT administered by microneedle array mediated TCI can be modulated by co-administration of adjuvants.


Sujet(s)
Adjuvants immunologiques/administration et posologie , Anatoxine diphtérique/administration et posologie , Anatoxine diphtérique/immunologie , Immunisation/méthodes , Administration par voie cutanée , Animaux , Production d'anticorps/effets des médicaments et des substances chimiques , Toxine cholérique/administration et posologie , Toxine cholérique/immunologie , Femelle , Immunisation/instrumentation , Immunoglobuline G/sang , Immunoglobuline G/immunologie , Lipopolysaccharides/administration et posologie , Lipopolysaccharides/immunologie , Souris , Souris de lignée BALB C , Oligodésoxyribonucléotides/administration et posologie , Oligodésoxyribonucléotides/immunologie , Saponines de Quillaja , Saponines/administration et posologie , Saponines/immunologie
5.
Vaccine ; 26(29-30): 3690-5, 2008 Jul 04.
Article de Anglais | MEDLINE | ID: mdl-18539369

RÉSUMÉ

Protection to tetanus is often not optimal in developing countries due to incomplete vaccination schemes, or decreased efficacy of vaccination. In this study we investigated the immunological response to tetanus booster vaccination in school children living in a semi-urban or in a rural area of Gabon. Tetanus-specific total IgG as well as antibody subclasses of the IgG1, IgG2, IgG3 and IgG4 isotype and the avidity of the dominating IgG1 subclass were determined both before and 1 month after the booster vaccination. In addition, tetanus-specific cytokine responses were determined. We found a polarization towards a T helper 1 (Th1) profile in the semi-urban children, whereas the cytokine responses of the rural children showed a T helper 2 (Th2) skewed response. Furthermore, tetanus-specific antibodies of the different IgG subclasses were all increased upon a tetanus booster vaccination and levels of IgG1 and IgG3 were higher in the rural children. In conclusion, a tetanus booster vaccination induced a stronger Th2 over Th1 cytokine profile to tetanus toxoid (TT) in rural children who showed the highest levels of IgG1 and IgG3 anti-TT antibody responses.


Sujet(s)
Anticorps antibactériens/sang , Lymphocytes T/immunologie , Anatoxine tétanique/immunologie , Tétanos/prévention et contrôle , Affinité des anticorps , Enfant , Cytokines/métabolisme , Femelle , Gabon , Humains , Rappel de vaccin , Immunoglobuline G/sang , Mâle , Population rurale , Population urbaine
6.
Parasite Immunol ; 30(1): 39-46, 2008 Jan.
Article de Anglais | MEDLINE | ID: mdl-18086015

RÉSUMÉ

Schistosomes carry lipid moieties that interact with the immune system. To understand the consequence of interactions in terms of polarizing the cytokine profiles, the effect of two Toll-like receptor-2 (TLR2) activating schistosomal lipid fractions was studied on whole blood from Gabonese children living in a schistosomiasis endemic area. One fraction contained lysophosphatidylserine [monoacylglycerophosphoserine (lysoGPSer)] plus diacylphosphatidylserine [diacylglycerophosphoserine (GPSer)] while the other contained lysoGPSer and only a trace of GPSer. The effect of these schistosomal lipid fractions was compared with the known bacterial TLR2 ligands PAM3CSK4 and MALP-2. PAM3CSK4 and MALP-2 had preferential IL-10-activating capacities, while the fraction containing lysoGPSer plus GPSer had a strong TNF-alpha-inducing capacity. The fraction containing lysoGPSer was neutral with respect to pro- vs. anti-inflammatory effects. When Th1 and Th2 cytokines were analysed, the schistosomal lipid fraction containing lysoGPSer plus GPSer showed a stronger Th2 response compared to PAM3CSK4, MALP-2 and lysoGPSer alone. Therefore, the study indicates that not only TLR2 ligands derived from bacteria or from parasites can generate distinct cytokine profiles but also that the composition of lipid entities reaching the immune system can be important in leading to different immune outcomes. This information may be important for exploitation of immune modulatory molecules.


Sujet(s)
Lysophospholipides/immunologie , Oligopeptides/immunologie , Peptides/immunologie , Schistosoma mansoni/immunologie , Récepteur de type Toll-2/immunologie , Adolescent , Animaux , Lignée cellulaire , Enfant , Enfant d'âge préscolaire , Cytokines/immunologie , Cytokines/métabolisme , Femelle , Gabon , Humains , Ligands , Lipopeptides , Lysophospholipides/isolement et purification , Lysophospholipides/métabolisme , Mâle , Oligopeptides/métabolisme , Peptides/métabolisme
7.
J Infect Dis ; 196(11): 1671-8, 2007 Dec 01.
Article de Anglais | MEDLINE | ID: mdl-18008252

RÉSUMÉ

BACKGROUND: With the current attention to the pandemic threat of avian influenza viruses, it is recognized that there is little information on influenza in Africa. In addition, the effects of influenza vaccination in African countries could be very different from the effects in regions with less exposure to microorganisms and parasites. METHODS: To monitor the presence of influenza viruses and investigate the immunological responses to influenza vaccination, schoolchildren in semi-urban and rural regions of Gabon were studied. Influenza-specific antibody responses to the 3 strains represented in the vaccine were determined in the serum. Furthermore, cytokine responses were measured after in vitro stimulation of whole blood by influenza antigens, before and after vaccination. RESULTS: Prevaccination titers of antibody against H3N2 were high. At vaccination, the titers of antibody against the 3 influenza strains increased significantly. The anti-H1N1 and anti-B responses after vaccination were weaker in rural schoolchildren than in semi-urban schoolchildren. Influenza-specific cytokine responses were induced within a week, showing significantly lower interferon- gamma and significantly higher interleukin-5 in the children from rural areas. CONCLUSIONS: Prevaccination antibody levels indicated that influenza viruses circulate in Gabon. Altogether, influenza vaccination induces weaker immune responses in a rural population than in a semi-urban population of Gabonese schoolchildren.


Sujet(s)
Anticorps antiviraux/sang , Cytokines/sang , Vaccins antigrippaux/usage thérapeutique , Grippe humaine/immunologie , Population rurale , Population des banlieues , Animaux , Anticorps antihelminthe/sang , Anticorps antiprotozoaires/sang , Production d'anticorps , Enfant , Femelle , Gabon , Humains , Immunité cellulaire , Sous-type H1N1 du virus de la grippe A/immunologie , Sous-type H3N2 du virus de la grippe A/immunologie , Vaccins antigrippaux/immunologie , Grippe humaine/virologie , Interféron gamma/sang , Interleukine-5/sang , Mâle , Facteurs temps
8.
Parasite Immunol ; 28(8): 363-71, 2006 Aug.
Article de Anglais | MEDLINE | ID: mdl-16879308

RÉSUMÉ

In addition to proteins, glycolipids can be targets of antibody responses and contribute to host-pathogen interaction. Following the structural analysis of Ascaris lumbricoides-derived glycolipids, the antibody responses of a group of children with no, light and heavy infections were analysed. The role of the phosphorylcholine moiety, present on Ascaris glycoproteins and glycolipids, in antibody reactivity of these infected individuals was determined. Children carrying heavy infections showed highest IgG reactivity to glycolipids compared to lightly or non-infected children. Substantial IgG antibody reactivity to both (glyco)proteins and glycolipids was found to be directed to the phosphorylcholine moiety as determined by either removal of this group or a competition assay. This was most pronounced for glycolipids, where removal of the phosphorylcholine moieties by hydrofluoric acid treatment abrogated IgG antibody reactivity. Measurement of IgG4 and IgE isotypes showed no IgG4 reactivity to Ascaris glycolipids, but raised IgE responses were detected in subjects with light or no Ascaris infections, suggesting that IgE responses to glycolipids may play a role in controlling parasite burden. Differences found in antibody profiles to glycolipids and (glyco)proteins, indicate that these different classes of compounds may have distinct roles in shaping of and interacting with humoral immune responses.


Sujet(s)
Anticorps antihelminthe/immunologie , Ascaridiose/immunologie , Ascaris lombricoides/immunologie , Glycolipides/immunologie , Glycoprotéines/immunologie , Phosphoryl-choline/immunologie , Animaux , Anticorps antihelminthe/sang , Antigènes d'helminthe/immunologie , Ascaris lombricoides/composition chimique , Ascaris suum/composition chimique , Ascaris suum/immunologie , Études cas-témoins , Enfant , Femelle , Glycolipides/composition chimique , Protéines d'helminthes/immunologie , Humains , Immunoglobuline E/sang , Immunoglobuline E/immunologie , Immunoglobuline G/sang , Immunoglobuline G/immunologie , Mâle , Spectrométrie de masse MALDI
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