ABSTRACT INTRODUCTION Serogroup B meningococcal outer membrane vesicle vaccines have been effective against vaccine-type strains, but their effectiveness against heterologous strains has been controversial. The Cuban VA-MENGOC-BCvaccine is of this type, but also includes meningococcus C capsular polysaccharide. OBJECTIVES Assess the effectiveness of VA-MENGOC-BC in reducing meningococcal disease caused by homologous or heterologous serogroup B strains and its serological effectiveness against meningococcus C. METHODS A review of studies of VA-MENGOC-BC’s application in Cuba, Brazil, Uruguay and Colombia was carried out to examine the vaccine’s effectiveness in reducing meningococcal disease during serogroup B outbreaks. Serological effectiveness against serogroup C determined in these studies (indicated by bactericidal antibody titers before and after vaccination) was also analyzed. RESULTS VA-MENGOC-BC’s effectiveness against homologous serogroup B strains has consistently been greater than 80% in all age groups. Effectiveness in heterologous contexts was also above 80% in individuals aged >4 years. Lower effectiveness in heterologous contexts was found in Brazilian children aged <2 years, although still >50%. Effectiveness increased when assessed based on mortality rates, as well as in cases of clinically severe meningococcal disease. The carrier-state pattern was modified after vaccination with reduction of hypervirulent lineages. Some 60% of infants (aged <1 year) attained protective bactericidal antibody titers against serogroup C. Higher protection rates were achieved in older children. CONCLUSIONS In addition to prevention of meningococcal disease caused by homologous serogroup B strains, VA-MENGOC-BC should be considered for heterologous contexts. It is protective against serogroup C in all age groups.

The conventional hybridoma technology has enabled the development of monoclonal antibodies (Mabs) against many antigens. Mabs have several applications in the field of basic research, diagnosis, immunotherapy and vaccine manufacturing processes. Mabs-producing hybridomas against the capsular polysaccharide from <i>Salmonella</i> Typhi were obtained, after intraperitoneal immunization of BALB/c mice with 10 µg of capsular polysaccharide Vi conjugated to diphtheria toxoid, and subsequent fusion of lymphocytes isolated of the spleen and myeloma cells SP2/O. A Mab was selected, partially characterized, and named as 4G3E11. The isotype of this Mab was IgG1. It was proved by means of a sandwich ELISA that the 4G3E11 Mab reacts with different concentrations of polysaccharide in samples of the vax-TyVi® vaccine. The Mab obtained in this research could be useful as reagent for the detection and quantitation of polysaccharide Vi in typhoid vaccines.

La tecnología clásica del hibridoma permitió el desarrollo de anticuerpos monoclonales (AcM) contra una inmensa variedad de antígenos, los cuales tienen diversas aplicaciones en el campo de la investigación básica, diagnóstico, inmunoterapia y en los procesos industriales de vacunas. En este trabajo se generaron hibridomas productores de AcM específicos contra el polisacárido capsular Vi de Salmonella Typhi, para lo cual se realizó la inmunización intraperitoneal de ratones BALB/c con 10 µg de polisacárido capsular Vi conjugado a Toxoide Diftérico y la subsiguiente fusión entre los linfocitos aislados del bazo y células de mieloma SP2/O. Se seleccionó y caracterizó un AcM que se denominó 4G3E11. El isotipo del AcM resultó IgG1. Se demostró que AcM 4G3E11 reconoce diferentes valores de concentración del polisacárido en muestras de vacunas vax-TyVi®, mediante un ELISA tipo sándwich. El AcM obtenido como parte de este estudio permitirá la identificación y cuantificación del polisacárido Vi en vacunas anti-tifoídicas.

In many countries, Cholera remains being a problem for human health, since it continues being an epidemic or endemic disease, which affects either children or adults and it is a death cause when cholera cases are not treated. A live oral vaccine against this disease can contribute to control important epidemics, mainly at countries where the sanitary hygienic conditions are not good or drinking water is not available. In this work, bio models were selected and applied for the selection of genetically attenuated Vibrio cholerae strains as vaccine candidates against cholera. Their toxigenicity, immunogenicity and protection were evaluated by means of Ileal Loops, intraduodenal inoculation and RITARD models in F1 (New Zealand x White Semi giant) young adults rabbits weighing from 1.8 to2.3 kg. The results obtained with the used bio models, show that the Vibrio cholerae genetically attenuated strains are no toxigenic, but are immunogenic and protective. As conclusion, these bio models are available for the evaluation and selection of oral vaccine candidates

El cólera es en muchos países un problema para la salud humana al mantenerse 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 contribuir a controlar importantes epidemias, principalmente en países donde las condiciones higiénicas sanitarias no son adecuadas o hay escasez de agua potable. En el presente trabajo se seleccionaron y aplicaron biomodelos para la evaluación de cepas atenuadas genéticamente de Vibrio cholerae, como candidatas vacunales contra el cólera. Para evaluar latoxigenicidad, inmunogenicidad y protección se utilizaron los modelos: IlealLoop, inoculación intraduodenal y RITARD en conejos F1 (Nueva Zelanda x Semigigante Blanco) adultos jóvenes con un peso entre 1,8-2,3 kg. Los resultados que se obtienen con los biomodelos utilizados demuestran que las cepas atenuadas genéticamente son no toxigénicas, son inmunogénicas y protectoras. Se concluye que los biomodelos que se utilizaron en este trabajo permiten la evaluación de cepas candidatas para vacunas vivas orales contra el cólera.