RESUMEN
The use of new adjuvants in vaccine formulations is a subject of current research. Only few parenteral adjuvants have been licensed. We have developed a mucosal and parenteral adjuvant known as AFCo1 (Adjuvant Finlay Cochleate 1, derived from proteoliposomes of N. meningitidis B) using a dialysis procedure to produce them on lab scale. The immunogenicity of the AFCo1 produced by dialysis has been already evaluated, but it was necessary to demonstrate the feasibility of a larger-scale manufacturing process. Therefore, we used a crossflow diafiltration system (CFS) that allows easy scale up to obtain large batches in an aseptic environment. The aim of this work was to produce AFCo1 on pilot scale, while conserving the adjuvant properties. The proteoliposomes (raw material) were resuspended in a buffer containing sodium deoxycholate and were transformed into AFCo1 under the action of a calcium forming buffer. The detergent was removed from the protein solution by diafiltration to a constant volume. In this CFS, we used a hollow fiber cartridge from Amicon (polysulfona cartridge of 10 kDa porosity, 1mm channel diameter of fiber and 0.45 m² area of filtration), allowing production of a batch of up to 20 L. AFCo1 were successfully produced by tangential filtration to pilot scale. The batch passed preliminary stability tests. Nasal immunization of BALB/c mice, induced specific saliva IgA and serum IgG. The induction of Th1 responses were demonstrated by the induction of IgG2a, IFNγ and not IL-5. The adjuvant action over Neisseria (self) antigens and with co-administered (heterologous) antigens such as ovalbumin and a synthetic peptide from haemolytic Streptococcus B was also demonstrated.
Asunto(s)
Adyuvantes Inmunológicos , Vacunas Meningococicas/biosíntesis , Neisseria meningitidis Serogrupo B/inmunología , Proteolípidos/inmunología , Adyuvantes Inmunológicos/administración & dosificación , Administración Intranasal , Animales , Anticuerpos Antibacterianos/sangre , Anticuerpos Antibacterianos/inmunología , Inmunización , Inmunoglobulina A/sangre , Inmunoglobulina A/inmunología , Inmunoglobulina G/sangre , Inmunoglobulina G/inmunología , Interferón gamma/biosíntesis , Interleucina-5/biosíntesis , Ratones , Ratones Endogámicos BALB C , Ovalbúmina/inmunología , Proyectos Piloto , Células TH1/inmunologíaRESUMEN
Spike-based COVID-19 vaccines induce potent neutralizing antibodies but their efficacy against SARS-CoV-2 variants decreases. OVX033 is a recombinant protein composed of the full-length nucleocapsid (N) protein of SARS-CoV-2 genetically fused to oligoDOM®, a self-assembling domain which improves antigen immunogenicity. OVX033 including N as an antigenic target is proposed as new vaccine candidate providing broad-spectrum protection against sarbecoviruses. OVX033 demonstrated its ability to trigger cross-reactive T cell responses and cross-protection against three variants of SARS-CoV-2 (B.1 Europe, Delta B.1.617.2, and Omicron B.1.1.529) in a hamster challenge model, as evidenced by lower weight loss, lower lung viral loads, and reduced lung histopathological lesions.
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COVID-19 , Vacunas , Animales , Cricetinae , Humanos , SARS-CoV-2 , Vacunas contra la COVID-19 , COVID-19/prevención & control , NucleocápsideRESUMEN
OVX836 is a recombinant protein-based vaccine targeting the highly conserved influenza nucleoprotein (NP), which aims to confer a broad-spectrum protection against influenza. In a Phase 1 study, OVX836, administered intramuscularly, has been found safe and immunogenic. The 90µg and 180µg dose levels were selected to be further evaluated in this randomized, monocenter, reference-controlled (Influvac Tetra™: quadrivalent seasonal influenza subunit vaccine), parallel group, double-blind, Phase 2a study in 300 healthy volunteers, aged 18-65 years, during the 2019/2020 flu season. Safety, influenza-like illness episodes (ILI; based on the Flu-PRO® questionnaire) and immunogenicity were assessed up to 180 days post-vaccination. OVX836 was safe and presented a reactogenicity profile similar to Influvac Tetra. It induced a significant increase in terms of NP-specific interferon-gamma (IFNγ) spot forming cells (SFCs), NP-specific CD4+ T-cells (essentially polyfunctional cells) and anti-NP IgG responses. OVX836 was superior to Influvac Tetra for all immunological parameters related to NP, and the 180µg dose was significantly superior to the 90µg dose for SFCs and CD4+ T-cells expressing IFNγ. Both the CD4+ T-cell and the anti-NP IgG responses persisted up to Day 180. An efficacy signal was observed with OVX836 at 180µg through reduction of ILI episodes occurring during the flu season as of 14 days post-vaccination. In conclusion, these results encourage further clinical evaluation of OVX836 in order to confirm the signal of efficacy on ILIs and/or laboratory-confirmed influenza cases. NCT04192500 (https://clinicaltrials.gov/ct2/show/study/NCT04192500).
Asunto(s)
Vacunas contra la Influenza , Gripe Humana , Adolescente , Adulto , Anciano , Método Doble Ciego , Humanos , Inmunoglobulina G , Vacunas contra la Influenza/efectos adversos , Gripe Humana/prevención & control , Interferón gamma , Persona de Mediana Edad , Nucleoproteínas , Vacunas Combinadas , Vacunas Sintéticas , Adulto JovenRESUMEN
Increasing emphasis is being placed on the mucosal administration of vaccines in order to stimulate mucosal as well as systemic responses. Findings from our group suggest that proteoliposome-derived cochleate (AFCo1) acts as a potent mucosal adjuvant. As an alternative to chemical conjugation, the current study aimed to determine the benefit of using AFCo1 to improve the mucosal and systemic immune responses to capsular polysaccharide of Neisseria meningitidis serogroup C (PsC), a model of a thymus-independent (TI) antigen. Therefore, intranasal (i.n.) immunization of 3 doses 1 week apart with AFCo1 plus PsC in mice was conducted. Highly specific anti-PsC IgA responses and an anti-PsC IgG response were obtained. The subclass pattern induced against PsC was similar to that induced with the meningococcal vaccine. In summary, AFCo1 as nasal adjuvant was demonstrated to be capable of eliciting mucosal and systemic specific responses against a TI antigen.
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Adyuvantes Inmunológicos/farmacología , Antígenos Bacterianos/inmunología , Cápsulas Bacterianas/inmunología , Vacunas Meningococicas/farmacología , Neisseria meningitidis Serogrupo C/inmunología , Proteolípidos/farmacología , Administración Intranasal , Animales , Anticuerpos Antibacterianos/análisis , Anticuerpos Antibacterianos/sangre , Ensayo de Inmunoadsorción Enzimática , Femenino , Inmunoglobulina A/análisis , Inmunoglobulina G/sangre , Inyecciones Intramusculares , Infecciones Meningocócicas/inmunología , Infecciones Meningocócicas/prevención & control , Vacunas Meningococicas/inmunología , Ratones , Ratones Endogámicos BALB C , Neisseria meningitidis Serogrupo C/química , Proteolípidos/inmunologíaRESUMEN
Mucosal immune responses are an early and important line of defense against pathogens. The current understanding of the mucosal immune system allows us to consider the use of nasal immunization for induction of antigen-specific immune responses at the mucosal surface and the systemic compartment. Mucosal adjuvants are key for developing novel mucosal vaccines and represent 1 approach to improving mucosal and systemic immunity. However, few mucosal vaccine adjuvants are currently approved for human use. Neisseria meningitidis B proteoliposome-derived cochleate (AFCo1 - Adjuvant Finlay Cochleate 1) has been demonstrated to be a potent mucosal adjuvant. The present work demonstrates that intranasal immunization of 3 doses of tetanus toxoid (TT) coadministered with AFCo1 in mice promotes high systemic and mucosal responses. The anti-TT IgG serum titers and the mucosal anti-TT IgA in saliva and vaginal wash were significantly higher than TT alone. The analysis of antibody subclasses showed that intranasal administration of AFCo1 + TT induced not only IgG1 but also IgG2a anti-TT antibodies at levels comparable to those obtained with TT vaccine (vax-TET). These data support the fact that AFCo1 is a potent mucosal adjuvant in nasal immunization to a coadministered protein antigen.
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Adyuvantes Inmunológicos/administración & dosificación , Inmunidad Mucosa , Inmunoglobulina G/sangre , Toxoide Tetánico/inmunología , Administración Intranasal , Administración Intravaginal , Animales , Formación de Anticuerpos , Femenino , Inmunoglobulina A Secretora/inmunología , Inmunoglobulina G/inmunología , Ratones , Ratones Endogámicos BALB C , Neisseria meningitidis Serogrupo B , Proteolípidos/administración & dosificación , Proteolípidos/inmunología , Saliva/inmunología , Toxoide Tetánico/administración & dosificación , Vagina/inmunologíaRESUMEN
Tissue-resident memory (TRM) CD8+ T-cells play a crucial role in the protection against influenza infection but remain difficult to elicit using recombinant protein vaccines. OVX836 is a recombinant protein vaccine, obtained by the fusion of the DNA sequence of the influenza A nucleoprotein (NP) to the DNA sequence of the OVX313 heptamerization domain. We previously demonstrated that OVX836 provides broad-spectrum protection against influenza viruses. Here, we show that OVX836 intramuscular (IM) immunization induces higher numbers of NP-specific IFNγ-producing CD8+ T-cells in the lung, compared to mutant NP (NPm) and wild-type NP (NPwt), which form monomeric and trimeric structures, respectively. OVX836 induces cytotoxic CD8+ T-cells and high frequencies of lung TRM CD8+ T-cells, while inducing solid protection against lethal influenza virus challenges for at least 90 days. Adoptive transfer experiments demonstrated that protection against diverse influenza subtypes is mediated by NP-specific CD8+ T-cells isolated from the lung and spleen following OVX836 vaccination. OVX836 induces a high number of NP-specific lung CD8+ TRM-cells for long-term protection against influenza viruses.
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Linfocitos T CD8-positivos/inmunología , Memoria Inmunológica , Virus de la Influenza A/inmunología , Vacunas contra la Influenza/inmunología , Gripe Humana/inmunología , Animales , Anticuerpos Antivirales/inmunología , Linfocitos T CD8-positivos/metabolismo , Modelos Animales de Enfermedad , Ensayo de Inmunoadsorción Enzimática , Ensayo de Immunospot Ligado a Enzimas , Humanos , Inmunización , Gripe Humana/prevención & control , Interferón gamma/metabolismo , Pulmón/inmunología , Pulmón/metabolismo , Pulmón/virología , Ratones , Proteínas de la Nucleocápside/química , Proteínas de la Nucleocápside/inmunología , Especificidad de Órganos/inmunologíaRESUMEN
Conservative estimates place the death toll from cholera at more than 100,000 persons each year. A particulate mucosal vaccine strategy combining antigens and immune stimulator molecules from Vibrio cholerae to overcome this problem is described. Proteoliposomes extracted from V. cholerae O1 were transformed into cochleates (AFCo2, Adjuvant Finlay cochleate 2) through a calcium inducible rotary dialysis method. Light microscopy was carried out and tubules of 16.25+/-4.57 microm in length were observed. Western blots were performed to verify the immunochemical properties of the main AFCo2 incorporated antigens, revealing full recognition of the outer membrane protein U (OmpU), lipopolysaccharide (LPS), and mannose-sensitive hemagglutinin (MSHA) antigens. AFCo2 were administered by the intranasal route using a two or three dose schedule and the immune response against V. cholerae antigens was assessed. Three AFCo2 doses were required to induce significant (p<0.05), antigen specific IgA in saliva (1.34+/-0.135) and feces (0.60+/-0.089). While, two or three doses of AFCo2 or proteoliposomes induce similar specific IgG and vibriocidal activity responses in sera. These results show for the first time that AFCo2 can be obtained from V. cholerae O1 proteoliposomes and have the potential to protect against the pathogen when administered intranasally.
Asunto(s)
Membrana Mucosa/inmunología , Proteolípidos/administración & dosificación , Proteolípidos/inmunología , Vibrio cholerae O1/inmunología , Administración Intranasal , Animales , Ácido Desoxicólico/administración & dosificación , Ácido Desoxicólico/inmunología , Ácido Edético/administración & dosificación , Ácido Edético/inmunología , Femenino , Inmunidad Mucosa/efectos de los fármacos , Inmunidad Mucosa/inmunología , Inmunoglobulina G/inmunología , Ratones , Ratones Endogámicos BALB C , Membrana Mucosa/efectos de los fármacosRESUMEN
Inactivated influenza vaccines (IIVs) lack broad efficacy. Cellular immunity to a conserved internal antigen, the nucleoprotein (NP), has been correlated to protection against pandemic and seasonal influenza and thus could have the potential to broaden vaccine efficacy. We developed OVX836, a recombinant protein vaccine based on an oligomerized NP, which shows increased uptake by dendritic cells and immunogenicity compared with NP. Intramuscular immunization in mice with OVX836 induced strong NP-specific CD4+ and CD8+ T-cell systemic responses and established CD8+ tissue memory T cells in the lung parenchyma. Strikingly, OVX836 protected mice against viral challenge with three different influenza A subtypes, isolated several decades apart and induced a reduction in viral load. When co-administered with IIV, OVX836 was even more effective in reducing lung viral load.
RESUMEN
INTRODUCTION: There is an urgent need for a new and effective tuberculosis vaccine because BCG does not sufficiently prevent pulmonary disease. IMX313 is a novel carrier protein designed to improve cellular and humoral immunity. MVA85A-IMX313 is a novel vaccine candidate designed to boost immunity primed by bacillus Calmette-Guérin (BCG) that has been immunogenic in pre-clinical studies. This is the first evaluation of IMX313 delivered as MVA85A-IMX313 in humans. METHODS: In this phase 1, open-label first-in-human trial, 30 healthy previously BCG-vaccinated adults were enrolled into three treatment groups and vaccinated with low dose MVA85A-IMX313 (group A), standard dose MVA85A-IMX313 (group B), or MVA85A (group C). Volunteers were followed up for 6 months for safety and immunogenicity assessment. RESULTS: The majority of adverse events were mild and there were no vaccine-related serious AEs. Both MVA85A-IMX313 and MVA85A induced a significant increase in IFN-γ ELISpot responses. There were no significant differences between the Ag85A ELISpot and intracellular cytokine responses between the two study groups B (MVA85A-IMX313) and C (MVA85A) at any time point post-vaccination. CONCLUSION: MVA85A-IMX313 was well tolerated and immunogenic. There was no significant difference in the number of vaccine-related, local or systemic adverse reactions between MVA85A and MVA85A-IMX313 groups. The mycobacteria-specific cellular immune responses induced by MVA85A-IMX313 were not significantly different to those detected in the MVA85A group. In light of this encouraging safety data, further work to improve the potency of molecular adjuvants like IMX313 is merited. This trial was registered on clinicatrials.gov ref. NCT01879163.
Asunto(s)
Vacunas contra la Tuberculosis/inmunología , Tuberculosis/prevención & control , Adulto , Anticuerpos Antibacterianos/sangre , Vacuna BCG/administración & dosificación , Citocinas/inmunología , Ensayo de Inmunoadsorción Enzimática , Ensayo de Immunospot Ligado a Enzimas , Femenino , Humanos , Inmunidad Celular , Inmunoglobulina G/sangre , Masculino , Persona de Mediana Edad , Vacunas contra la Tuberculosis/administración & dosificación , Vacunas contra la Tuberculosis/efectos adversos , Vacunas de ADN , Adulto JovenRESUMEN
The purpose of this study was to investigate the potential of intranasal (IN) immunization with Neisseria meningitides B proteoliposome (AFPL1) and AFPL1-derived cochleate (AFCo1), containing glycoprotein D (gD) of herpes simplex virus type 2 (HSV-2) for induction of protective immunity against genital herpes infection in mice. We could show that IN immunization with both AFPL1 and AFCo1 containing gD induced gD-specific IgG antibody and lymphoproliferative responses. However, IFN-gamma response could only be detected in CD4(+) splenic cells and genital lymph node cells of the AFCo1gD immunized mice upon recall antigen stimulation in vitro. Importantly, IN immunization with AFCo1gD could elicit a complete protection against an otherwise lethal vaginal challenge with HSV-2, while the AFPL1gD immunized mice were only partially protected. Further, we could show that the IFN-gamma response and protective immunity observed after IN immunization with AFCo1gD are mediated via the adaptor molecule myeloid differentiation factor 88. These data may have implications for the development of a mucosal vaccine against genital herpes.
Asunto(s)
Herpes Genital/prevención & control , Herpesvirus Humano 2/inmunología , Proteínas del Envoltorio Viral/inmunología , Proteínas del Envoltorio Viral/farmacología , Administración Intranasal , Animales , Anticuerpos Antivirales/inmunología , Antígenos Bacterianos/inmunología , Antígenos Bacterianos/farmacología , Linfocitos T CD4-Positivos/inmunología , Femenino , Herpes Genital/genética , Herpes Genital/inmunología , Inmunización , Inmunoglobulina G/inmunología , Interferón gamma/inmunología , Liposomas , Ratones , Ratones Noqueados , Factor 88 de Diferenciación Mieloide/genética , Factor 88 de Diferenciación Mieloide/inmunología , Neisseria meningitidis Serogrupo B/inmunología , Proteínas Recombinantes/genética , Proteínas Recombinantes/inmunología , Proteínas Recombinantes/farmacología , Proteínas del Envoltorio Viral/genéticaRESUMEN
The polysaccharides (Ps) are thymus-independent 2 (TI-2) antigens and poor immunogens in infants and young children; as a result of this delayed response to Ps antigens during ontogeny, infants and young children are highly susceptible to infections caused by encapsulated bacteria. Meningococcal group C polysaccharide (PsC)-proteins conjugate vaccines have been reported to induce significant serum IgG antibodies and immunologic memory in infants resulting in very effective vaccines. We describe here the obtainment, by a new method, of a neoglycoconjugate intended to immunize against Neisseria meningitidis serogroup C, its characterization by physico-chemical methods, including (1)H NMR and fluorescence spectroscopy methods, as well as the characterization of the immune response induced in mice by such conjugate. Amine groups generated by basic hydrolysis in the PsC were successfully conjugated to carboxyl groups of tetanus toxoid (TT), using carbodiimide-mediated coupling. The specific anti-Ps IgG and anti-Ps IgG subclasses (IgG1 and IgG2a) were measured by ELISA methods, the bactericidal activity in sera and the cytokines response (IFNgamma or IL5) in spleen cell of mice immunized with conjugated and native Ps were evaluated. The (1)H NMR spectra and the result obtained by the fluorescence spectroscopy method showed that the PsC and TT maintained structural identity after conjugation process. Conjugated PsC elicited an increase of anti-PsC IgG responses, anti-PsC IgG subclass (IgG1, IgG2a), an eight-fold increase in bactericidal activity in sera of mice immunized with conjugate compared with native PsC, was also observed. Higher titres of IFNgamma were observed in mice immunized with conjugated Ps. These results indicated that, the PsC and TT maintained its chemical and antigenic structure after the conjugation process. A change in the immunological pattern of responses of PsC, from TI-2 to a thymus-dependent (TD) pattern, was also demonstrated.
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Meningitis Meningocócica/prevención & control , Vacunas Meningococicas/inmunología , Polisacáridos Bacterianos/inmunología , Toxoide Tetánico/inmunología , Animales , Anticuerpos Antibacterianos/sangre , Anticuerpos Antibacterianos/clasificación , Modelos Animales de Enfermedad , Femenino , Inmunoglobulina G/sangre , Inmunoglobulina G/clasificación , Interferón gamma/biosíntesis , Interleucina-5/biosíntesis , Linfocitos/inmunología , Espectroscopía de Resonancia Magnética , Ratones , Ratones Endogámicos BALB C , Viabilidad Microbiana , Neisseria meningitidis/inmunología , Polisacáridos Bacterianos/química , Espectrometría de Fluorescencia , Toxoide Tetánico/químicaRESUMEN
Alkylglycerols (AGs) have shown immune stimulant and adjuvant activity in many studies, but natural sources are not so accessible and their extraction from them is very complicated. Therefore, a group of chemists at IFAL have synthesized AG analogs. The aim of this work was to evaluate the adjuvant potential of different synthetic AGs. A mix of ovoalbumin (Ova) and AGs increase anti-Ova IgG antibodies production in sera of immunized mice. The predominant subclass was IgG1 although higher levels of IgG2a were observed as the carbon chain length of AGs increased. AGs also induced the production of IL-12 and nitric oxide (NO) in the U937 human histiocyte and J774 mouse macrophage cell lines, respectively. These results indicate that synthetic AGs are effective adjuvants for the standardized antigen, Ova.
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Adyuvantes Inmunológicos/farmacología , Glicerol/análogos & derivados , Glicerol/farmacología , Adyuvantes Inmunológicos/química , Animales , Línea Celular , Histiocitos/inmunología , Humanos , Macrófagos/inmunología , Ratones , Ovalbúmina/inmunologíaRESUMEN
Cochleate structures obtained from the outer membrane of Neisseria meningitidis serotype B have demonstrated to be high immunogenicity when administrated by intramuscular, oral or intranasal routes, and could be used as adjuvant and meningococcal nasal vaccine candidate. Due to the microparticulate nature of Cochleate it is necessary to control the particle size since it capture by cells of the immune system could be affected by this aspect. We combined optic microscopy and immunisation experiments to select the optimum particle size. Six different processes of producing Cochleate obtaining were evaluated and different mechanical stress conditions were carried out to homogenize and modulate the particles size. The more immunogenic particles were selected on the basis of the levels of specific IgA and IgG antibodies induced after intranasal immunisation in mice. The best treatment parameter for mechanical stress of the Cochleate was prolonged treatment with untrasonic low frequency waves.
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Adyuvantes Inmunológicos/química , Vacunas Meningococicas/química , Neisseria meningitidis Serogrupo B , Proteolípidos/química , Adyuvantes Inmunológicos/aislamiento & purificación , Adyuvantes Inmunológicos/farmacología , Animales , Vacunas Meningococicas/inmunología , Ratones , Ratones Endogámicos BALB C , Microscopía , Neisseria meningitidis Serogrupo B/química , Tamaño de la Partícula , Proteolípidos/aislamiento & purificación , Proteolípidos/farmacologíaRESUMEN
Cochleate structures (CS) consist in a highly stable lipid structures that have been reported to be a good antigen delivery system. The incorporation of pathogen associated molecular pattern (PAMP) from bacterial membranes into CS became in a promising approach to develop adjuvants, particularly mucosal adjuvants. Therefore, we prepare CS from proteoliposome (PL) obtained from Neisseria meningitidis B (PLCS) and evaluated it for its capability to stimulate the immune system as well as the adjuvant activity. The ability of PLCS to induce Thl polarization was also explored. The results and the easy capability for new antigen incorporation on CS support its use as adjuvant for immunization with a large variety of pathogen derived antigens and different routes of immunization.
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Adyuvantes Inmunológicos/farmacología , Proteolípidos/inmunología , Adyuvantes Inmunológicos/química , Animales , Células Cultivadas , Células Dendríticas/inmunología , Humanos , Linfocitos/inmunología , Macrófagos/inmunología , Ratones , Neisseria meningitidis/química , Neisseria meningitidis/inmunología , Proteolípidos/químicaRESUMEN
One current approach in developing anti allergic vaccines is the use of potent adjuvants, capable of inducing Th1 or T regulatory cells. Proteoliposomes (PL) could be a suitable adjuvant. Purified Dermatophagoides siboney (Ds) allergens were mixed with PL and adsorbed into Al(OH)3 and evaluated in mice. The Th1/Th2 responses were measured at classes, subclasses, cytokines, and DTH levels. Anti Ds response was deviated to a Thl pattern, with the production of IgG2a and gamma1FN. A positive DTH response and a dramatic decrease of specific IgE and IL5 were not detected. The low dose was more effective than high dose. These results clearly support the potential use of PL as possible adjuvants for anti-allergic vaccines.
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Adyuvantes Inmunológicos/farmacología , Antígenos Dermatofagoides/inmunología , Hipersensibilidad/prevención & control , Proteolípidos/inmunología , Vacunas/inmunología , Hidróxido de Aluminio/administración & dosificación , Animales , Antígenos Dermatofagoides/administración & dosificación , Ratones , Neisseria meningitidis Serogrupo B/inmunología , Proteolípidos/administración & dosificaciónRESUMEN
We evaluated the potential of two bacterial derived compounds, Cochleate and Proteoliposome (PL), administrated to mice by nasal or oral routes on induction of antibody and cytokine responses. Anti PL IgG and IgA responses were measured by ELISA in saliva, sera or vaginal fluids of immunized mice. Productions of gammaIFN and IL-5 were determined in spleen cells of immunized mice following a recall in vitro with Cochleate or PL. Intranasal administration elicited a higher anti PL IgA response in both saliva and vaginal fluids as compared with oral route. Mice immunized with Cochleate or PL via intranasal or oral route-induced anti PL IgG and IgG2a antibody responses in their sera and vaginal fluids. Spleen cells from these immunized mice produced gammaIFN, but not IL-5, after a recall in vitro with Cochleate or PL. These results show that Cochleate and PL are capable of inducing both systemic and mucosal antibody responses as well as a Th1 type of immunity as evidenced by high gammaIFN and IgG2a antibody responses.
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Adyuvantes Inmunológicos/farmacología , Inmunidad Mucosa , Proteolípidos/farmacología , Adyuvantes Inmunológicos/administración & dosificación , Administración Intranasal , Administración Oral , Animales , Femenino , Linfocitos/inmunología , Ratones , Neisseria meningitidis , Proteolípidos/administración & dosificación , Bazo/inmunologíaRESUMEN
We evaluated the adjuvant properties and toxicity of purified Neisseria meningitidis serogroup B lipopolysaccharide (LPS) conjugated with tetanus toxoid (TT) using a new method of conjugation to obtain amine groups in the polysaccharide structure. The endotoxic activity of treated LPS was reduced 2400 times as determined by Limulus amoebocyte assay and no mortality was observed in Balb/c mice inoculated with detoxified LPS versus 100% mortality in native LPS inoculated mice. The conjugated LPS-TT elicited in mice higher anti-TT IgG2a and IgG1 than unconjugated TT. In addition, high levels of anti-LPS IgG and IgG subclasses were detected in sera. These results evidence the adjuvant activity of detoxified LPS and may suggest that the conjugation to TT changes the LPS immune response from thymus-independent to thymus-dependent.
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Adyuvantes Inmunológicos/farmacología , Lipopolisacáridos/farmacología , Neisseria meningitidis Serogrupo B , Toxoide Tetánico/inmunología , Adyuvantes Inmunológicos/química , Adyuvantes Inmunológicos/toxicidad , Animales , Lipopolisacáridos/química , Lipopolisacáridos/toxicidad , Ratones , Ratones Endogámicos BALB C , Vacunas Conjugadas/inmunologíaRESUMEN
Mucosal delivery of vaccines represents an attractive approach because this is a region of first contact point for inhaled antigens. We have obtained a meningococcal group C polysaccharide-tetanus toxoid conjugate (MGCP-TT) and evaluated it for intranasal route in mice. The conjugate was obtained by a developed method in our laboratory. The specific IgA in saliva and specific IgA and IgG in serum were measured by ELISA methods and bactericidal antibodies in sera against a meningococcal group C strain were measured. The conjugated elicited a significant increase in anti-MGCP salivary IgA and serum IgG and bactericidal antibodies concentrations, while specific serum IgA was not observed. These results indicated that after conjugation, there was a change in the responses for MGCP from thymus-independent to thymus-dependent and that it was effective by intranasal route.
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Inmunidad Mucosa , Vacunas Meningococicas/inmunología , Toxoide Tetánico/inmunología , Administración Intranasal , Animales , Anticuerpos Antibacterianos/sangre , Ratones , Ratones Endogámicos BALB C , Neisseria meningitidis , Toxoide Tetánico/química , Vacunas Conjugadas/inmunologíaRESUMEN
We describe a new method to obtain conjugates against Neisseria meningitidis serogroups A, B, C, Vibrio cholera, and Salmonella typhi and their immunogenicity in Balb/c mice. The saccharides were activated by basic hydrolysis with the generation of amine groups in the saccharidic chain, and these groups were linked to carboxyl groups of tetanus toxoid by via carbodiimida-mediated reaction. The resultant conjugates were administered to mice for the immunogenicity studies. The pirogenicity of LPS was measured by LAL assay. The anti-saccharide IgG, IgG1, and IgG2a antibodies were evaluated. A significant decrease in the pirogenicity of LPS after basic hydrolysis treatment was observed. The conjugates elicited higher titers of anti-polysaccharides or anti-LPS IgG, IgG1, and IgG2a in conjugates than in unconjugated saccharides. The results indicate that we have a new method for obtaining conjugated vaccines and we have demonstrated that after conjugation there was a change in the responses for all saccharides, from thymus-independent to thymus-dependent responses.
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Lipopolisacáridos/química , Toxoide Tetánico/química , Vacunas Conjugadas/química , Animales , Anticuerpos Antibacterianos/sangre , Inmunoglobulina G/sangre , Lipopolisacáridos/inmunología , Ratones , Ratones Endogámicos BALB C , Neisseria meningitidis/química , Neisseria meningitidis/inmunología , Salmonella typhi/química , Salmonella typhi/inmunología , Toxoide Tetánico/inmunología , Vacunas Conjugadas/aislamiento & purificación , Vibrio cholerae/química , Vibrio cholerae/inmunologíaRESUMEN
Cochleate are highly stable structures with promising immunological features. Cochleate structures are usually obtaining from commercial lipids. Proteoliposome derived Cochleate are derived from an outer membrane vesicles of Neisseria meningitidis B. Previously, we obtained Cochleates using dialysis procedures. In order to increase the production process, we used a crossflow system (CFS) that allows easy scale up to obtain large batches in an aseptic environment. The raw material and solutions used in the production process are already approved for human application. This work demonstrates that CFS is very efficient process to obtain Cochleate structures with a yield of more than 80% and the immunogenicity comparable to that obtained by dialysis membrane.