A COVID-19 vaccine candidate composed of the SARS-CoV-2 RBD dimer and Neisseria meningitidis outer membrane vesicles.

SARS-CoV-2 infection is mediated by the interaction of the spike glycoprotein trimer via its receptor-binding domain (RBD) with the host's cellular receptor. Vaccines seek to block this interaction by eliciting neutralizing antibodies, most of which are directed toward the RBD. Many protein subunit vaccines require powerful adjuvants to generate a potent antibody response. Here, we report on the use of a SARS-CoV-2 dimeric recombinant RBD combined with Neisseria meningitidis outer membrane vesicles (OMVs), adsorbed on alum, as a promising COVID-19 vaccine candidate. This formulation induces a potent and neutralizing immune response in laboratory animals, which is higher than that of the dimeric RBD alone adsorbed on alum. Sera of people vaccinated with this vaccine candidate, named Soberana01, show a high inhibition level of the RBD-ACE2 interaction using RBD mutants corresponding to SARS-CoV-2 variants of concern and wild-type expressed using the phage display technology. To our knowledge, this is the first time that the immunostimulation effect of N. meningitidis OMVs is evaluated in vaccine candidates against SARS-CoV-2.

Repeat-Dose Toxicity Study Using the AFPL1-Conjugate Nicotine Vaccine in Male Sprague Dawley Rats.

Tobacco smoking is the cause of 20% of Canadian deaths per year. Nicotine vaccines present a promising alternative to traditional smoking cessation products, but to date, no vaccine has been able to move through all phases of clinical trials. We have previously demonstrated that the AFPL1-conjugate nicotine vaccine does not induce systemic or immunotoxicity in a mouse model and that a heterologous vaccination approach is more advantageous than the homologous routes to inducing mucosal and systemic anti-nicotine antibodies. The purpose of this study was to confirm the safety profile of the vaccine in a repeat-dose toxicity study. The heterologous vaccination strategy was again used, and Sprague Dawley rats were administered a dose five times greater than in our previous studies. Physiological conditions, food and water consumption, body temperature, injection site inflammation, relative weights of organs, histopathology, and blood chemistry and hematology were evaluated during the course of the vaccination period to determine the safety of the vaccine. The AFPL1-conjugate nicotine vaccine did not induce clinically relevant changes or induce symptoms that would be associated with toxicity, making it a promising candidate for future investigations.

Assessing the immunogenicity and toxicity of the AFPL1-conjugate nicotine vaccine using heterologous and homologous vaccination routes.

Despite the increased risks of cancers and cardiovascular related diseases, tobacco smoking continues to be prevalent in the population due largely in part to the addictive nature of nicotine. Nicotine vaccines are an attractive alternative to the current smoking cessation options but have yet to be successful enough in clinical trials to reach the market due to a lack of neutralizing antibodies and inconsistent results. Using AFPL1 derived from the Cuban meningococcal vaccine as an adjuvant, we have previously published promising results with an intranasally administered nicotine vaccine. In order to examine the immunogenicity and safety of this vaccine in mice we set up a pilot trial administering the vaccine either intranasally, intramuscularly or utilizing both routes simultaneously and evaluated immune responses and clinical symptoms throughout the duration of the vaccination protocol and post-mortem. These data further demonstrate the ability of the AFPL1 nicotine conjugate vaccine to be a safe and potential candidate for clinical use.

Evaluating the immunogenicity of an intranasal vaccine against nicotine in mice using the Adjuvant Finlay Proteoliposome (AFPL1).

Tobacco smoking is recognized as a global pandemic resulting in 6 million deaths per year. Despite a variety of anti-smoking products available to aid with tobacco cessation, the majority of people who attempt to quit smoking relapse within 6 months due to the addictive nature of nicotine. An immunotherapy approach could offer a promising treatment option by inducing a potent selective antibody response against nicotine in order to block its distribution to the brain and its addictive effects in the central nervous system. Our nicotine vaccine candidate was administered intranasally using the Neisseria meningitidis serogroup B Adjuvant Finlay Proteoliposome 1 (AFPL1) as a part of the delivery system. This system was designed to generate a robust immune response by stimulating IL-1ß production through Toll-like receptor 4 (TLR4), a potent mechanism for mucosal immunity. The vaccine induced high antibody titers in mice sera in addition to inducing mucosal antibodies. The efficacy of our vaccine was demonstrated using in vivo challenge experiments with radioactive [(3)H]-nicotine, followed by an analysis of nicotine distribution in the lung, liver, blood and brain. Our results were encouraging as the nicotine concentration in the brain tissue of mice vaccinated with our candidate vaccine was four times lower than in non-vaccinated controls; suggesting that the anti-nicotine antibodies were able to block nicotine from crossing the blood brain barrier. In summary, we have developed a novel nicotine vaccine for the treatment of tobacco addiction by intranasal administration and also demonstrated that the AFPL1 can be used as a potential adjuvant for this vaccine design.

Combined meningococcal serogroup A and W135 outer-membrane vesicles activate cell-mediated immunity and long-term memory responses against non-covalent capsular polysaccharide A.

Outer-membrane vesicles (OMVs) have inherent adjuvant properties, and many vaccines use OMV as vaccine components. Utilizing the adjuvant properties of OMV could lead to the formulation of vaccines that are less expensive and potentially more immunogenic than covalently conjugated polysaccharide vaccines. We evaluated the adjuvant effect in Balb/c mice of combinations of OMV from Neisseria meningitidis serogroup A and W135 as compared to that of the non-covalently conjugated capsular polysaccharide A. Both antigens were adsorbed onto aluminum hydroxide. The mice were given a booster dose of plain polysaccharide A to stimulate an immunologic memory response. Subclasses determination and cytokine assays demonstrated the capacity of OMV to induce a IgG2a/IgG2b isotype profile and IFN-γ production, suggesting the induction of a Th1 pattern immune response. Lymphoproliferative responses to OMVs were high, with affinity maturation of antibodies observed. Bactericidal titers after the booster dose were also observed. Memory B cells and long-term memory T cells were also detected. The results of this study indicate that combined meningococcal serogroup A and W135 OMV can activate cell-mediated immunity and induce a long-term memory response.

Repeated dose toxicity study of Vibrio cholerae-loaded gastro-resistant microparticles.

CONTEXT: Microencapsulation of antigens has been extensively studied over the last decades aiming at improving the immunogenicity of vaccine candidates. OBJECTIVE: Addressing microparticles (MPs) toxicity in rats. MATERIAL AND METHODS: Spray-dried Eudragit® L 30 D-55 MPs and Eudragit® L 30 D-55 alginate MPs were elaborated and characterized. MPs obtained were administered to rats, three groups were defined: G1, control group; G2, administered with Vibrio cholerae (VC)-loaded MPs; G3, receiving VC-loaded alginate MPs. Animals received three vaccine doses. Body weight, food and water intake were controlled during the study. Haematological parameters, vibriocidal titres, organ weight and histology in necropsy were also analyzed. RESULTS: All animals grew healthy. Body weight gain, food and water intake and haematological parameters remained within physiological values, showing no treatment-related differences. Moreover, organ weight changes were not detected and animals developed protective vibriocidal titres. CONCLUSION: VC-loaded MPs and VC-loaded alginate MPs have proved to be safe and effective in the assessed conditions.

Plan de actividades físico-recreativas para ocupar el tiempo libre en jóvenes desvinculados del estudio y el trabajo / Plan of physical and recreational activities to spend the spare time of young population dissociated from study and job

A través del deporte comunitario se pretende promover la práctica de la actividad física, la recreación y las actividades deportivas para acercar a un mayor número de habitantes a los servicios y programas que se ofrecen, y la orientación y asesoría permanente que permiten optimizar el desarrollo de esos programas deportivos. El presente artículo tiene el objetivo de elaborar un plan de actividades físico recreativo que contribuya a la ocupación del tiempo libre en los jóvenes desvinculados del estudio y el trabajo del Consejo Popular Hermanos Barcón del municipio Pinar del Río. Se realizaron las entrevistas a los líderes de la comunidad y se encuestaron a jóvenes que no estudian, ni trabajan para comprobar sus preferencias en cuanto a las actividades físico recreativo y el tiempo libre que poseen. Se desarrolló a partir de estas motivaciones un plan de actividades deportivo recreativas que haga posible que los jóvenes de esta comunidad se motiven hacia actividades socialmente útiles y no dediquen ese tiempo a conductas socialmente inadecuadas, el hábito de fumar o la ingestión de bebidas alcohólicas, siendo esta una contribución más al desarrollo de mejores estilos de vida(AU)

This research paper was aimed at creating a plan of physical-recreational activities which contributes to spend the spare time of young population dissociated from study and job at Hermanos Barcon Popular Council, Pinar del Rio municipality. The leaders of the community were interviewed, applying surveys to the target population, in order to learn about their preferences regarding physical-recreational activities and their spare time, designing a plan of sports-recreational activities that motivates the youths towards social-useful activities avoiding this way their participation in social-inappropriate conducts, smoking or the consumption of alcoholic drinks, playing a significant part the development of better lifestyles(AU)

Plan de actividades físico-recreativas para ocupar el tiempo libre en jóvenes desvinculados del estudio y el trabajo / Plan of physical and recreational activities to spend the spare time of young population dissociated from study and job

A través del deporte comunitario se pretende promover la práctica de la actividad física, la recreación y las actividades deportivas para acercar a un mayor número de habitantes a los servicios y programas que se ofrecen, y la orientación y asesoría permanente que permiten optimizar el desarrollo de esos programas deportivos. El presente artículo tiene el objetivo de elaborar un plan de actividades físico recreativo que contribuya a la ocupación del tiempo libre en los jóvenes desvinculados del estudio y el trabajo del Consejo Popular "Hermanos Barcón" del municipio Pinar del Río. Se realizaron las entrevistas a los líderes de la comunidad y se encuestaron a jóvenes que no estudian, ni trabajan para comprobar sus preferencias en cuanto a las actividades físico recreativo y el tiempo libre que poseen. Se desarrolló a partir de estas motivaciones un plan de actividades deportivo recreativas que haga posible que los jóvenes de esta comunidad se motiven hacia actividades socialmente útiles y no dediquen ese tiempo a conductas socialmente inadecuadas, el hábito de fumar o la ingestión de bebidas alcohólicas, siendo esta una contribución más al desarrollo de mejores estilos de vida.

This research paper was aimed at creating a plan of physical-recreational activities which contributes to spend the spare time of young population dissociated from study and job at “Hermanos Barcon” Popular Council, Pinar del Rio municipality. The leaders of the community were interviewed, applying surveys to the target population, in order to learn about their preferences regarding physical-recreational activities and their spare time, designing a plan of sports-recreational activities that motivates the youths towards social-useful activities avoiding this way their participation in social-inappropriate conducts, smoking or the consumption of alcoholic drinks, playing a significant part the development of better lifestyles.

Pharmacology and toxicology of an oral tablet whole cells inactivated cholera vaccine in Sprague Dawley rats.

Here we further investigate the pharmacological and toxicological properties of a cholera vaccine based on inactivated whole cells presented in either enteric coated (COA) or uncoated (U/C) tablet formulation from Vibrio cholerae C7258 strain. Tablets were dispersed in 2mL drinking water and administered orally to Sprague Dawley rats distributed in five groups (I COA7, II U/C7 immunized at 0, 7, 69days and III COA14, IV U/C14 immunized at 0, 14, 69days and V control group). Serum vibriocidal antibody response was measured after the administration of two doses with an interval of 7-14days. To further investigate the toxicological aspects a third dose was applied 10 weeks after the initial one. Animals were observed daily and water and food consumption was measured every other day. Periodic blood extractions were performed for hematology, biochemistry, and the titer of serum vibriocidal antibodies was determined. Anatomopathological analysis was performed at days 3 or 14 after the third dose. Results from clinical observations, as well as from water and food consumption and body weigh indicated no toxicity of the vaccine product. Meanwhile, no biological differences were found among different groups in hematological, hemo-chemistry, and anatomopathological studies. Moreover, enteric coated and uncoated tablets against human cholera were found to induce an immune response in rats.

Intranasal administration of proteoliposome-derived cochleates from Vibrio cholerae O1 induce mucosal and systemic immune responses in mice.

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.

Biomodelo para la evaluación de cepas atenuadas como candidatosvacunales contra el cólera humano I: estudio de la virulencia, capacidadde colonización y adherencia a la mucosa intestinal / Biomodel for evaluating attenuated Vibrio cholerae strains as human cholera vaccine candidates I: virulence, colonizing capacity and adherence to the intestinal mucosa

El cólera continúa siendo en muchos países un problema para la salud humana, manteniéndose como una enfermedad epidémica o endémica que afecta tanto a niños como adultos y causa la muerte en casos no tratados. Una vacuna viva oral contra esta enfermedad puede ser la solución. En el presente trabajo se seleccionó y aplicó un biomodelo para la evaluación de cepas atenuadas genéticamente de Vibrio cholerae como candidatas vacunales contra el cólera. La virulencia, capacidad de colonización y adherencia a la mucosa intestinal de las cepas fueron evaluadas mediante el usode ratones neonatos de 2 a 4 días de nacidos de la línea Balb/c, con un peso entre 1,5-2 g. Los resultados obtenidos con este biomodelo demostraron que las cepas atenuadas genéticamente son no virulentas, colonizan y se adhieren a lamucosa intestinal. Se concluye que el biomodelo utilizado permite la evaluación y selección de cepas candidatas para vacunas vivas orales contra el cólera(AU)

Cholera is still a human health problem in many countries. It is an epidemic or endemic disease affecting both children and adults that causes death of untreated cases. A live oral vaccine could be the solution against this disease. In the present study a biomodel was selected and applied for the evaluation of genetically attenuated Vibrio cholerae strains as vaccinecandidates. The virulence, colonizing capacity and adherence to the intestinal mucosa of the strains were evaluated using 2-4 day-old neonatal Balb/c mice, weighing from 1.5-2 g. The results obtained with this biomodel showed that genetically attenuated strains are not virulent, colonize and adhere to the intestinal mucosa. The conclusion was that the biomodel used allows the evaluation and selection of candidate strains for live oral cholera vaccines(AU)