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1.
J Travel Med ; 30(7)2023 11 18.
Artículo en Inglés | MEDLINE | ID: mdl-37099803

RESUMEN

BACKGROUND: No licensed human vaccines are available against enterotoxigenic Escherichia coli (ETEC), a major diarrhoeal pathogen affecting children in low- and middle-income countries and foreign travellers alike. ETVAX®, a multivalent oral whole-cell vaccine containing four inactivated ETEC strains and the heat-labile enterotoxin B subunit (LTB), has proved promising in Phase 1 and Phase 1/ 2 studies. METHODS: We conducted a Phase 2b double-blinded, randomized, placebo-controlled trial amongst Finnish travellers to Benin, West Africa. This report presents study design and safety and immunogenicity data. Volunteers aged 18-65 years were randomized 1:1 to receive ETVAX® or placebo. They visited Benin for 12 days, provided stool and blood samples and completed adverse event (AE) forms. IgA and IgG antibodies to LTB and O78 lipopolysaccharide (LPS) were measured by electrochemiluminescence. RESULTS: The AEs did not differ significantly between vaccine (n = 374) and placebo (n = 375) recipients. Of the solicited AEs, loose stools/diarrhoea (26.7/25.9%) and stomach ache (23.0/20.0%) were reported most commonly. Of all possibly/probably vaccine-related AEs, the most frequent were gastrointestinal symptoms (54.0/48.8%) and nervous system disorders (20.3/25.1%). Serious AEs were recorded for 4.3/5.6%, all unlikely to be vaccine related. Amongst the ETVAX® recipients, LTB-specific IgA antibodies increased 22-fold. For the 370/372 vaccine/placebo recipients, the frequency of ≥2-fold increases against LTB was 81/2.4%, and against O78 LPS 69/2.7%. The majority of ETVAX® recipients (93%) responded to either LTB or O78. CONCLUSIONS: This Phase 2b trial is the largest on ETVAX® undertaken amongst travellers to date. ETVAX® showed an excellent safety profile and proved strongly immunogenic, which encourages the further development of this vaccine.


Asunto(s)
Escherichia coli Enterotoxigénica , Niño , Humanos , Benin , Vacunas de Productos Inactivados , Finlandia , Lipopolisacáridos , África Occidental , Diarrea/prevención & control , Inmunoglobulina A
2.
Vaccine ; 41(21): 3347-3357, 2023 05 16.
Artículo en Inglés | MEDLINE | ID: mdl-37085452

RESUMEN

The feared diarrheal disease cholera remains an important global health problem. Use of oral cholera vaccine (OCV) from a global stockpile against both epidemic and endemic cholera is a cornerstone in the World Health Organisations (WHOs) global program for "Ending cholera by 2030". Three liquid inactivated whole-cell OCVs (Dukoral®, ShancholTM, and Euvichol-Plus®) are WHO prequalified and have proved to be safe and effective. However, their multicomponent composition and cold-chain requirement increase manufacturing, storage and transport costs. ShancholTM and Euvichol-Plus® OCVs used in WHOs global vaccine stockpile also lack the protective cholera toxin B-subunit (CTB) antigen present in Dukoral®, which results in suboptimal efficacy. WHOs Global Task Force on Cholera Control (GTFCC) has identified a thermostable, dry formulation vaccine as a priority for further OCV development. We describe here the development of such a vaccine, based on a lyophilized mixture of a single strain of formalin-killed Hikojima bacteria together with a low-cost, recombinantly produced CTB. The new vaccine, which is easy and inexpensive to manufacture, could be stored for at least 26 months at 25 °C and for at least 8 months at 40 °C with preservation of cell morphology and with no loss of protective Ogawa and Inaba lipopolysaccharides or CTB. It also proved to be well tolerated and to have equivalent oral immunogenicity in mice as ShancholTM and Dukoral® OCVs with regard to both serum and intestinal-mucosal antibody responses.


Asunto(s)
Vacunas contra el Cólera , Cólera , Vibrio cholerae , Animales , Ratones , Toxina del Cólera , Cólera/prevención & control , Lipopolisacáridos , Administración Oral , Vacunas de Productos Inactivados
3.
Mucosal Immunol ; 16(1): 1-2, 2023 02.
Artículo en Inglés | MEDLINE | ID: mdl-36634818
4.
Mucosal Immunol ; 15(5): 1028-1039, 2022 05.
Artículo en Inglés | MEDLINE | ID: mdl-35729204

RESUMEN

The lack of clinically applicable mucosal adjuvants is a major hurdle in designing effective mucosal vaccines. We hereby report that the calcium-binding protein S100A4, which regulates a wide range of biological functions, is a potent mucosal adjuvant in mice for co-administered antigens, including the SARS-CoV-2 spike protein, with comparable or even superior efficacy as cholera toxin but without causing any adverse reactions. Intranasal immunization with recombinant S100A4 elicited antigen-specific antibody and pulmonary cytotoxic T cell responses, and these responses were remarkably sustained for longer than 6 months. As a self-protein, S100A4 did not stimulate antibody responses against itself, a quality desired of adjuvants. S100A4 prolonged nasal residence of intranasally delivered antigens and promoted migration of antigen-presenting cells. S100A4-pulsed dendritic cells potently activated cognate T cells. Furthermore, S100A4 induced strong germinal center responses revealed by both microscopy and mass spectrometry, a novel label-free technique for measuring germinal center activity. Importantly, S100A4 did not induce olfactory bulb inflammation after nasal delivery, which is often a safety concern for nasal vaccination. In conclusion, S100A4 may be a promising adjuvant in formulating mucosal vaccines, including vaccines against pathogens that infect via the respiratory tract, such as SARS-CoV-2.


Asunto(s)
Adyuvantes Inmunológicos , Inmunidad Mucosa , Proteína de Unión al Calcio S100A4 , Vacunas , Administración Intranasal , Animales , Humanos , Ratones , Ratones Endogámicos BALB C , Proteínas Recombinantes/inmunología , Proteína de Unión al Calcio S100A4/inmunología , SARS-CoV-2 , Glicoproteína de la Espiga del Coronavirus/inmunología , Linfocitos T Citotóxicos/inmunología
5.
Lancet Infect Dis ; 22(10): e292-e298, 2022 10.
Artículo en Inglés | MEDLINE | ID: mdl-35533702

RESUMEN

Cholera causes substantial morbidity and mortality in the world's poorest populations. For nearly a decade, an inactivated oral cholera vaccine (OCV) stockpile has been available to control and prevent outbreaks. In 2017, WHO launched a bold global initiative to reduce mortality from cholera by 90% by 2030, a cornerstone of which is deployment of OCVs from the global stockpile. The current production of OCVs for the stockpile falls well short of the doses needed to accomplish this goal. Besides efforts to enlist additional manufacturers of the current OCVs in the stockpile, inclusion of new-generation inactivated OCVs already in clinical development might offer advantages of enlarged production, improved performance, simplified logistics, and reduced costs. However, logistical, scientific, and ethical barriers make conventional, randomised, phase 3 clinical efficacy trials towards licensure of such new-generation OCVs problematic. The serum vibriocidal antibody response, the traditional immunological surrogate of protection against cholera, is imperfect for use as a standalone outcome. In this Personal View, we describe the need for new thinking on approaches for licensure and recommendations for new-generation inactivated OCVs, and suggest a pathway based on a sequential combination of immunogenicity and effectiveness observational studies.


Asunto(s)
Vacunas contra el Cólera , Cólera , Administración Oral , Cólera/epidemiología , Brotes de Enfermedades/prevención & control , Humanos , Vacunas de Productos Inactivados
6.
J Infect Dis ; 224(12 Suppl 2): S742-S748, 2021 12 20.
Artículo en Inglés | MEDLINE | ID: mdl-34453544

RESUMEN

The rapid spread of the seventh cholera pandemic over Asia in the 1960s led to several large field studies that revealed that the traditional injectable cholera vaccines had poor efficacy, which led the World Health Organization (WHO) in the 1970s to stop recommending cholera vaccination. At the same time, it stimulated research that has led to the development of the effective orally administered cholera vaccines (OCVs) that today are a cornerstone in WHO's strategy for Ending Cholera-A Global Roadmap to 2030. The first effective OCV, Dukoral, containing a mixture of inactivated Vibrio cholerae bacteria and cholera toxin B subunit, was licensed in 1991 and is, together with 2 similar inactivated whole-cell OCVs, Shanchol and Euvichol, currently WHO prequalified and recommended OCVs. This brief review is a personal account of the modern history of the development of these now universally recognized effective tools.


Asunto(s)
Vacunas contra el Cólera/historia , Cólera/prevención & control , Membrana Mucosa/inmunología , Vibrio cholerae/inmunología , Administración Oral , Historia del Siglo XX , Humanos , Inmunidad Colectiva , Vacunas de Productos Inactivados
7.
Vaccine ; 39(32): 4450-4457, 2021 07 22.
Artículo en Inglés | MEDLINE | ID: mdl-34218960

RESUMEN

BACKGROUND: The World Health Organization (WHO) recommends the use of oral cholera vaccines (OCVs) as part of an integrated control program, both in highly endemic settings and during cholera epidemics. The available and internationally recommended WHO-prequalified OCVs (Dukoral, Shanchol, Euvichol) contain multiple heat and formalin-killed V. cholerae strains of Inaba and Ogawa serotypes. MSD Wellcome Trust Hilleman Laboratories Pvt. Ltd. in technical collaboration with University of Gothenburg, Sweden has developed a new single strain OCV, Hillchol. This vaccine consists of formaldehyde-inactivated whole cell El Tor V. cholerae O1 bacteria engineered into the Hikojima serotype for stable expression of both the Ogawa (AB) and Inaba (AC) LPS antigens on the bacterial surface. We evaluated the safety and immunogenicity of this novel and potentially much less expensive OCV in comparison with Shanchol. METHODS: We conducted a randomized, non-inferiority, age-descending clinical trial of OCV (Hillchol vs. Shanchol) in the Mirpur area of Dhaka city from July 2016 to May 2017. This study was carried out in three different age cohorts (1-<5, 5-17 and ≥18 years old). Two doses of vaccine were given at 14 days intervals to 560 healthy participants. FINDINGS: No serious adverse events were reported. There were no significant differences in the rates of adverse events between the test vaccine (Hillchol) and the comparator (Shanchol) group. Serum vibriocidal antibody responses in all age groups combined were comparable for all the O1 Ogawa (59% vs. 67%; 90% CI of difference: -14.55, -0.84) and Inaba (70% vs. 71%; 90% CI of difference: -7.24, 5.77) serotypes, showing that the Hillchol vaccine was non-inferior to Shanchol. This new vaccine was also non-inferior to Shanchol in the different age strata. CONCLUSION: The safety and immunogenicity profile of the new OCV Hillchol is comparable to Shanchol in persons residing in a cholera-endemic setting. ClinicalTrials.gov number: NCT02823899.


Asunto(s)
Vacunas contra el Cólera , Cólera , Vibrio cholerae O1 , Administración Oral , Adolescente , Anticuerpos Antibacterianos , Bangladesh , Cólera/prevención & control , Humanos , Suecia , Vacunas de Productos Inactivados/efectos adversos
8.
Trop Med Infect Dis ; 6(2)2021 04 28.
Artículo en Inglés | MEDLINE | ID: mdl-33925118

RESUMEN

Individual resistance to cholera infection and disease depends on both innate host factors and adaptive immunity acquired by a previous infection or vaccination. Locally produced, intestinal-mucosal secretory IgA (SIgA) antibodies against bacterial surface lipopolysaccharide (LPS) O antigens and/or secreted cholera toxins are responsible for the protective adaptive immunity, in conjunction with an effective mucosal immunologic memory that can elicit a rapid anamnestic SIgA antibody response upon re-exposure to the antigen/pathogen even many years later. Oral cholera vaccines (OCVs), based on inactivated Vibrio cholerae whole-cell components, either together with the cholera toxin B subunit (Dukoral™) or administered alone (Shanchol™/Euvichol-Plus™) were shown to be consistently safe and effective in large field trials in all settings. These OCVs are recommended by the World Health Organisation (WHO) for the control of both endemic cholera and epidemic cholera outbreaks. OCVs are now a cornerstone in WHO's global strategy found in "Ending Cholera: A Global Roadmap to 2030." However, the forecasted global demands for OCV, estimated by the Global Alliance for Vaccines and Immunization (GAVI) to 1.5 billion doses for the period 2020-2029, markedly exceed the existing manufacturing capacity. This calls for an increased production capacity of existing OCVs, as well as the rapid introduction of additional and improved vaccines under development.

9.
Vascul Pharmacol ; 140: 106863, 2021 10.
Artículo en Inglés | MEDLINE | ID: mdl-33857652

RESUMEN

Patients suffering from systemic lupus erythematosus (SLE) are at increased risk of developing cardiovascular disease (CVD) and traditional therapies including statins provide insufficient protection. Impaired removal of apoptotic material is a common pathogenic mechanism in both SLE and atherosclerosis and is considered to be a key factor in the development of autoimmunity. Since oxidized LDL and apoptotic material bind to the same receptors, we aimed to investigate if targeting the oxidized LDL autoimmunity can affect atherosclerosis in SLE. To investigate the possible role of oxidized LDL autoimmunity in the accelerated atherosclerosis associated with SLE we used a hypercholesterolemic SLE mouse model (B6.lpr.ApoE-/- mice). Promoting LDL tolerance through mucosal immunization with an apolipoprotein B-100 peptide p45 (amino acids 661-680) and cholera toxin B-subunit fusion protein increased regulatory T cells and B cells in mesenteric lymph nodes and reduced plaque development in the aorta by 33%. Treatment with the oxidized LDL-specific antibody Orticumab reduced aortic atherosclerosis by 43%, subvalvular plaque area by 50% and the macrophage content by 31%. The present study provides support for oxLDL as a possible target for prevention of cardiovascular complications in SLE.


Asunto(s)
Aterosclerosis , Lupus Eritematoso Sistémico , Animales , Aterosclerosis/etiología , Aterosclerosis/metabolismo , Aterosclerosis/prevención & control , Autoinmunidad , Humanos , Lipoproteínas LDL , Lupus Eritematoso Sistémico/complicaciones , Lupus Eritematoso Sistémico/patología , Ratones
10.
Vaccine ; 38(50): 7998-8009, 2020 11 25.
Artículo en Inglés | MEDLINE | ID: mdl-33139137

RESUMEN

Cholera remains an important global health problem with up to 4 million cases and 140,000 deaths annually. Oral cholera vaccines (OCVs) are now a cornerstone of the WHOs "Ending Cholera - A Global Roadmap to 2030" global program for the eventual elimination of cholera. There are currently three WHO prequalified OCVs available, Dukoral®, Shanchol® and Euvichol-Plus®. These vaccines are effective but due to a multiple strain composition and two different methods of inactivation, are complex and costly to manufacture. We describe here the characterization and industrial scale development of Hillchol®; a novel, likely affordable single-component OCV for low and middle-income countries. Hillchol® consists of formalin-inactivated bacteria of a stable recombinant Vibrio cholerae O1 El Tor Hikojima serotype strain expressing approximately 50% each of Ogawa and Inaba O1 LPS antigens. The novel OCV can be manufactured on an industrial scale at a low cost. Hillchol® was well tolerated in animal toxicology studies and shown to have non-inferior oral immunogenicity in mice for both intestinal-mucosal and serological immune responses when compared with a WHO-prequalified OCV. The optimized production of this single component OCV will reduce cost of OCV production and thus substantially increase vaccine availability. Based on these results, Hillchol® has been produced at a GMP facility and used successfully for clinical phase I/II studies.


Asunto(s)
Vacunas contra el Cólera , Cólera , Vibrio cholerae O1 , Administración Oral , Animales , Anticuerpos Antibacterianos , Cólera/prevención & control , Ratones , Serogrupo , Vacunas de Productos Inactivados , Vibrio cholerae O1/genética
11.
Evolution ; 74(10): 2377-2391, 2020 10.
Artículo en Inglés | MEDLINE | ID: mdl-32885859

RESUMEN

Spectacular long-distance migration has evolved repeatedly in animals enabling exploration of resources separated in time and space. In birds, these patterns are largely driven by seasonality, cost of migration, and asymmetries in competition leading most often to leapfrog migration, where northern breeding populations winter furthest to the south. Here, we show that the highly aerial common swift Apus apus, spending the nonbreeding period on the wing, instead exhibits a rarely found chain migration pattern, where the most southern breeding populations in Europe migrate to wintering areas furthest to the south in Africa, whereas the northern populations winter to the north. The swifts concentrated in three major areas in sub-Saharan Africa during the nonbreeding period, with substantial overlap of nearby breeding populations. We found that the southern breeding swifts were larger, raised more young, and arrived to the wintering areas with higher seasonal variation in greenness (Normalized Difference Vegetation Index) earlier than the northern breeding swifts. This unusual chain migration pattern in common swifts is largely driven by differential annual timing and we suggest it evolves by prior occupancy and dominance by size in the breeding quarters and by prior occupancy combined with diffuse competition in the winter.


Asunto(s)
Migración Animal , Evolución Biológica , Aves/genética , África , Animales , Tamaño Corporal , Tamaño de la Nidada , Europa (Continente)
12.
Assay Drug Dev Technol ; 18(4): 157-179, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32407132

RESUMEN

Evaluation and optimization of physicochemical and metabolic properties of compounds are a crucial component of the drug development process. Continuous access to this information during the design-make-test-analysis cycle enables identification of chemical entities with suitable properties for efficient project progression. In this study, we describe an integrated and automated assay panel (DMPK Wave 1) that informs weekly on lipophilicity, solubility, human plasma protein binding, and metabolic stability in rat hepatocytes and human liver microsomes. All assays are running in 96-well format with ultraperformance liquid chromatography-mass spectrometry (MS)/MS as read-out. A streamlined overall workflow has been developed by optimizing all parts of the process, including shipping of compounds between sites, use of fit-for-purpose equipment and information systems, and technology for compound requesting, data analysis, and reporting. As a result, lead times can be achieved that well match project demands across sites independently of where compounds are synthesized. This robust screening strategy is run on a weekly basis and enables optimization of structure-activity relationships in parallel with DMPK properties to allow efficient and informed decision making.


Asunto(s)
Preparaciones Farmacéuticas/química , Preparaciones Farmacéuticas/metabolismo , Animales , Automatización , Cromatografía Líquida de Alta Presión , Hepatocitos/química , Hepatocitos/metabolismo , Humanos , Espectrometría de Masas , Microsomas Hepáticos/química , Microsomas Hepáticos/metabolismo , Ratas
14.
NPJ Vaccines ; 4: 45, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31666991

RESUMEN

Helicobacter pylori causes chronic gastric infection that can lead to peptic ulcers and is an identified risk factor for gastric cancer development. Although much effort has been put into the development of a Helicobacter pylori vaccine over the last three decades, none has yet reached clinical application. Specific challenges pertaining to effective H. pylori vaccine development include the lack of proven vaccine-effective antigens and safe mucosal adjuvants to enhance local immune responses as well as the lack of accepted correlates of protection. Herein, we demonstrate that prophylactic intragastric immunisation with a whole-cell killed H. pylori antigen administered together with the non-toxic oral adjuvant α-galactosylceramide (α-GalCer) induced effective immune protection against H. pylori infection in mice, which was of similar magnitude as when using the "gold standard" cholera toxin as adjuvant. We further describe that this α-GalCer-adjuvanted vaccine formulation elicited strong intestinal and systemic Th1 responses as well as significant antigen-specific mucosal and systemic antibody responses. Finally, we report that the protective intestinal Th1 responses induced by α-GalCer are dependent on CD1d, IL-1R as well as IL-17R signalling. In summary, our results show that α-GalCer is a promising adjuvant for inclusion in an oral vaccine against H. pylori infection.

15.
Front Immunol ; 10: 2214, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31616417

RESUMEN

Immaturity of the immune system contributes to poor vaccine responses in early life. Germinal center (GC) activation is limited due to poorly developed follicular dendritic cells (FDC), causing generation of few antibody-secreting cells (ASCs) with limited survival and transient antibody responses. Herein, we compared the potential of five adjuvants, namely LT-K63, mmCT, MF59, IC31, and alum to overcome limitations of the neonatal immune system and to enhance and prolong responses of neonatal mice to a pneumococcal conjugate vaccine Pnc1-TT. The adjuvants LT-K63, mmCT, MF59, and IC31 significantly enhanced GC formation and FDC maturation in neonatal mice when co-administered with Pnc1-TT. This enhanced GC induction correlated with significantly enhanced vaccine-specific ASCs by LT-K63, mmCT, and MF59 in spleen 14 days after immunization. Furthermore, mmCT, MF59, and IC31 prolonged the induction of vaccine-specific ASCs in spleen and increased their persistence in bone marrow up to 9 weeks after immunization, as previously shown for LT-K63. Accordingly, serum Abs persisted above protective levels against pneumococcal bacteremia and pneumonia. In contrast, alum only enhanced the primary induction of vaccine-specific IgG Abs, which was transient. Our comparative study demonstrated that, in contrast to alum, LT-K63, mmCT, MF59, and IC31 can overcome limitations of the neonatal immune system and enhance both induction and persistence of protective immune response when administered with Pnc1-TT. These adjuvants are promising candidates for early life vaccination.


Asunto(s)
Adyuvantes Inmunológicos/farmacología , Células Productoras de Anticuerpos/efectos de los fármacos , Médula Ósea/efectos de los fármacos , Centro Germinal/efectos de los fármacos , Bazo/efectos de los fármacos , Compuestos de Alumbre/farmacología , Animales , Animales Recién Nacidos , Anticuerpos Antibacterianos/sangre , Toxinas Bacterianas/farmacología , Médula Ósea/inmunología , Toxina del Cólera/farmacología , Combinación de Medicamentos , Enterotoxinas/farmacología , Proteínas de Escherichia coli/farmacología , Inmunoglobulina G/sangre , Ratones , Oligodesoxirribonucleótidos/farmacología , Oligopéptidos/farmacología , Vacunas Neumococicas/administración & dosificación , Polisorbatos/farmacología , Bazo/inmunología , Escualeno/farmacología
16.
Mucosal Immunol ; 12(4): 1055-1064, 2019 07.
Artículo en Inglés | MEDLINE | ID: mdl-30953000

RESUMEN

Cholera is a severe diarrheal disease caused by the bacterium Vibrio cholerae (V. cholerae) that results in 3-4 million cases globally with 100,000-150,000 deaths reported annually. Mostly confined to developing nations, current strategies to control the spread of cholera include the provision of safe drinking water and improved sanitation and hygiene, ideally in conjunction with oral vaccination. However, difficulties associated with the costs and logistics of these strategies have hampered their widespread implementation. Specific challenges pertaining to oral cholera vaccines (OCVs) include a lack of safe and effective adjuvants to further enhance gut immune responses, the complex and costly multicomponent vaccine manufacturing, limitations of conventional liquid formulation and the lack of an integrated delivery platform. Herein we describe the use of the orally active adjuvant α-Galactosylceramide (α-GalCer) to strongly enhance intestinal bacterium- and toxin-specific IgA responses to the OCV, Dukoral® in C57BL/6 and BALB/c mice. We further demonstrate the mucosal immunogenicity of a novel multi-antigen, single-component whole-cell killed V. cholerae strain and the enhancement of its immunogenicity by adding α-GalCer. Finally, we report that combining these components and recombinant cholera toxin B subunit in the SmPill® minisphere delivery system induced strong intestinal and systemic antigen-specific antibody responses.


Asunto(s)
Vacunas contra el Cólera/inmunología , Galactosilceramidas/farmacología , Inmunidad Mucosa/efectos de los fármacos , Inmunomodulación/efectos de los fármacos , Adyuvantes Inmunológicos/administración & dosificación , Administración Oral , Animales , Anticuerpos Antibacterianos/inmunología , Cólera/inmunología , Cólera/prevención & control , Vacunas contra el Cólera/administración & dosificación , Modelos Animales de Enfermedad , Femenino , Galactosilceramidas/administración & dosificación , Inmunización , Masculino , Ratones , Subgrupos de Linfocitos T/inmunología , Subgrupos de Linfocitos T/metabolismo , Células TH1/inmunología , Células TH1/metabolismo , Vibrio cholerae/inmunología
17.
Front Immunol ; 10: 269, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-30838003

RESUMEN

Cholera toxin (CT) is widely used as an effective adjuvant in experimental immunology for inducing mucosal immune responses; yet its mechanisms of adjuvant action remain incompletely defined. Here, we demonstrate that mice lacking NFκB, compared to wild-type (WT) mice, had a 90% reduction in their systemic and mucosal immune responses to oral immunization with a model protein antigen [Ovalbumin (OVA)] given together with CT. Further, NFκB-/- mouse dendritic cells (DCs) stimulated in vitro with CT showed reduced expression of MHCII and co-stimulatory molecules, such as CD80 and CD86, as well as of IL-1ß, and other pro-inflammatory cytokines compared to WT DCs. Using a human monocyte cell line THP1 with an NFκB activation reporter system, we show that CT induced NFκB signaling in human monocytes, and that inhibition of the cyclic AMP-protein kinase A (cAMP-PKA) pathway abrogated the activation and nuclear translocation of NFκB. In a human monocyte-CD4+ T cell co-culture system we further show that the strong Th17 response induced by CT treatment of monocytes was abolished by blocking the classical but not the alternative NFκB signaling pathway of monocytes. Our results indicate that activation of classical (canonical) NFκB pathway signaling in antigen-presenting cells (APCs) by CT is important for CT's adjuvant enhancement of Th17 responses. Similar findings were obtained using the almost completely detoxified mmCT mutant protein as adjuvant. Altogether, our results demonstrate that activation of the classical NFκB signal transduction pathway in APCs is important for the adjuvant action of both CT and mmCT.


Asunto(s)
Toxina del Cólera/inmunología , Proteínas Quinasas Dependientes de AMP Cíclico/metabolismo , AMP Cíclico/metabolismo , FN-kappa B/metabolismo , Transducción de Señal/fisiología , Adyuvantes Inmunológicos/metabolismo , Animales , Células Presentadoras de Antígenos/inmunología , Células Presentadoras de Antígenos/metabolismo , Antígenos/inmunología , AMP Cíclico/inmunología , Proteínas Quinasas Dependientes de AMP Cíclico/inmunología , Células Dendríticas/inmunología , Células Dendríticas/metabolismo , Femenino , Inmunidad Mucosa/inmunología , Ratones , Ratones Endogámicos C57BL , Monocitos/inmunología , Monocitos/metabolismo , FN-kappa B/inmunología , Ovalbúmina/inmunología , Transducción de Señal/inmunología , Células Th17/inmunología , Células Th17/metabolismo
18.
Sci Rep ; 9(1): 2812, 2019 02 26.
Artículo en Inglés | MEDLINE | ID: mdl-30808871

RESUMEN

Cholera Toxin (CT) as well as its related non-toxic mmCT and dmLT mutant proteins have been shown to be potent adjuvants for mucosally administered vaccines. Their adjuvant activity involves activation of cAMP/protein kinase A (PKA) signaling and inflammasome/IL-1ß pathways in antigen presenting cells (APC). To get a further understanding of the signal transduction and downstream pathways activated in APCs by this group of adjuvants we have, employing quantitative proteomic analytic tools, investigated human monocytes at various time points after treatment with CT. We report the activation of three main biological pathways among upregulated proteins, peaking at 16 hours of CT treatment: cellular organization, metabolism, and immune response. Specifically, in the further analyzed immune response pathway we note a strong upregulation of thrombospondin 1 (THBS1) and integrin ß1 (ITGB1) in response to CT as well as to mmCT and dmLT, mediated via cAMP/PKA and NFKB signaling. Importantly, inhibition in vitro of THSB1 and ITGB1 in monocytes or primary dendritic cells using siRNA abrogated the ability of the treated APCs to promote an adjuvant-stimulated Th17 cell response when co-cultured with peripheral blood lymphocytes indicating the involvement of these molecules in the adjuvant action on APCs by CT, mmCT and dmLT.


Asunto(s)
Toxina del Cólera/farmacología , Integrina beta1/metabolismo , Monocitos/efectos de los fármacos , Monocitos/metabolismo , Proteómica , Trombospondina 1/metabolismo , Regulación hacia Arriba/efectos de los fármacos , Adyuvantes Inmunológicos/farmacología , AMP Cíclico/metabolismo , Proteínas Quinasas Dependientes de AMP Cíclico/metabolismo , Células Dendríticas/efectos de los fármacos , Células Dendríticas/metabolismo , Humanos , FN-kappa B/metabolismo , Transducción de Señal/efectos de los fármacos
19.
Vascul Pharmacol ; 111: 54-61, 2018 12.
Artículo en Inglés | MEDLINE | ID: mdl-30243560

RESUMEN

OBJECTIVE: Intranasal immunization with a fusion protein of the ApoB100-derived peptide p210 and the cholera toxin B subunit (CTB-p210) has previously been shown to induce mucosal tolerance and reduce atherosclerosis development, but the exact mode of action remains to be elucidated. Recent studies have indicated an important role for B cells in mucosal tolerance, in particular by induction of regulatory B (Bregs) and T cells (Tregs). In this study, we aimed to investigate if transfer of B cells pulsed with CTB-p210 can protect against atherosclerosis. METHOD AND RESULTS: First, we studied if CTB-p210 can induce Bregs and Tregs in vitro. After pulsing B cells from Apobtm2Sgyldlr-/- or Apoe-/- mice with CTB-p210 for 1 h and co-culturing them with naïve T cells for 48 h, we observed increased expression of membrane bound TGFß/latency-associated peptide (mTGFß/LAP) on B cells and an increased proportion of CD25hiFoxP3+ Tregs. Adoptive transfer of B cells pulsed with CTB-p210 into high-fat diet-fed Apoe-/- mice at 8, 10 and 12 weeks of age, reduced the plaque area in the aorta at 20 weeks of age as compared with control-treated (CTB-pOVA treated B cells or PBS) mice. Moreover, mice receiving p210-CTB treated B cells had increased levels of anti-p210 IgG antibodies. CONCLUSION: Our observations suggest that CTB-p210 pulsed B cells acquire a regulatory phenotype and induce Tregs in vitro. Adoptive transfer of CTB-p210, but not control-treated, B cells into Apoe-/- mice decreased atherosclerosis development.


Asunto(s)
Traslado Adoptivo , Enfermedades de la Aorta/prevención & control , Aterosclerosis/prevención & control , Linfocitos B Reguladores/efectos de los fármacos , Linfocitos B Reguladores/trasplante , Toxina del Cólera/farmacología , Factores Inmunológicos/farmacología , Animales , Aorta/inmunología , Aorta/metabolismo , Aorta/patología , Enfermedades de la Aorta/inmunología , Enfermedades de la Aorta/metabolismo , Enfermedades de la Aorta/patología , Aterosclerosis/inmunología , Aterosclerosis/metabolismo , Aterosclerosis/patología , Linfocitos B Reguladores/inmunología , Linfocitos B Reguladores/metabolismo , Células Cultivadas , Técnicas de Cocultivo , Modelos Animales de Enfermedad , Femenino , Humanos , Ratones Noqueados para ApoE , Fenotipo , Placa Aterosclerótica , Receptores de LDL/deficiencia , Receptores de LDL/genética , Linfocitos T Reguladores/inmunología , Linfocitos T Reguladores/metabolismo
20.
Vaccine ; 36(41): 6223-6230, 2018 10 01.
Artículo en Inglés | MEDLINE | ID: mdl-30119923

RESUMEN

Mucosal vaccines against Helicobacter pylori consisting of either whole cell bacteria or recombinant antigens can induce immune protection against challenge in mice only when co-administrated with a strong mucosal adjuvant such as cholera toxin (CT) or Escherichia coli heat labile enterotoxin (LT). The strong enterotoxicity of these adjuvants however preclude their use in human vaccines. The recently developed multiple mutant CT (mmCT) is a strong, yet practically non-toxic novel mucosal adjuvant which here was admixed with a formalin-inactivated H. pylori whole cell vaccine (WCV) as a potential vaccine candidate against H. pylori infection. We report that intragastric immunizations with H. pylori WCV together with mmCT, similar to immunization with WCV together with CT, resulted in 50-125-fold reduction in colonization of H. pylori in the stomach of mice associated with rises in both serum IgG and intestinal-mucosal IgA anti-H. pylori antibody responses and strong T cell and IFNγ and IL-17A cytokine responses. Data presented in this study also supports that the proposed vaccine can be grown in a bioreactor and would be effective against infection caused by a multitude of pathogenic H. pylori strains isolated from patients from various continents. The results warrant immunization studies in humans to evaluate the safety, immunogenicity and efficacy of the proposed H. pylori WCV and mmCT.


Asunto(s)
Toxina del Cólera/metabolismo , Infecciones por Helicobacter/prevención & control , Helicobacter pylori/inmunología , Adyuvantes Inmunológicos , Animales , Antígenos Bacterianos/inmunología , Toxinas Bacterianas/inmunología , Vacunas Bacterianas/inmunología , Vacunas Bacterianas/uso terapéutico , Toxina del Cólera/genética , Femenino , Infecciones por Helicobacter/inmunología , Helicobacter pylori/patogenicidad , Ratones , Ratones Endogámicos C57BL
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