New proteoliposome vaccine formulation from N. meningitidis serogroup B, without aluminum hydroxide, retains its antimeningococcal protectogenic potential as well as Th-1 adjuvant capacity.

Proteoliposomes purified from the Outer Membrane of Neisseria meningitidis B, have been successfully used as core for adjuvants and vaccine formulations. We have tried to increase their structural definition and to conserve their efficacy and stability avoiding the addition of the aluminum hydroxide to the final formulation. Liposomal particle systems were prepared from components of defined molecular structure, such as a Neisseria meningitidis B protein complex, extracted and purified without forming vesicle structures. Liposomes were prepared from a mixture of dioleoyl phosphatidyl serine and cholesterol, using the classical dehydration-rehydration method. Transmission Electron Microscopy (TEM) was used to characterize the liposomes. BALB/c mice were used for animal testing procedures. Analysis of specific IgG response, serum bactericidal activity as well as DTH reaction was carried out. Isolation and purification of mRNA and real-time PCR, was performed to determine the dominating Th lymphokine pattern. The new antimeningococcal formulation without aluminum hydroxide prepared with components of defined molecular structure assembled itself into Neoproteoliposomes (NPL) ranging from 50 to 70 nm in diameter. The extraction and purification of selected membrane proteins to provide the antigen for this new formulation (PD-Tp), as well as the NPL-formulation favors a Th1 response pattern, suggested by the higher percentages of DTH, increased expression of proinflamatory lymphokine mRNAs when administered by intramuscular and intranasal routes. It stimulates a systemic bactericidal antibody response against Neisseria meningitidis B and immunologic memory similar to the Cuban VA-MENGOC-BC vaccine, even at lower dosages and is less reactogenic at the injection site in comparison with the formulation with aluminum hydroxide. This new adjuvant formulation could be applicable to the development of new and improved vaccines against meningococcal disease, and eventually as modulators of the immune response against other diseases.

Multilevel analysis of social, climatic and entomological factors that influenced dengue occurrence in three municipalities in Colombia.

According to the World Health Organization, dengue is a neglected tropical disease. Latin America, specifically Colombia is in alert regarding this arbovirosis as there was a spike in the number of reported dengue cases at the beginning of 2019. Although there has been a worldwide decrease in the number of reported dengue cases, Colombia has shown a growing trend over the past few years. This study performed a Poisson multilevel analysis with mixed effects on STATA® version 16 and R to assess sociodemographic, climatic, and entomological factors that may influence the occurrence of dengue in three municipalities for the period 2010-2015. Information on dengue cases and their sociodemographic variables was collected from the National Public Health Surveillance System (SIVIGILA) records. For climatic variables (temperature, relative humidity, and precipitation), we used the information registered by the weather stations located in the study area, which are managed by the Instituto de Hidrologia, Meteorologia y Estudios Ambientales (IDEAM) or the Corporación Autónoma Regional (CAR). The entomological variables (house index, container index, and Breteau index) were provided by the Health office of the Cundinamarca department. SIVIGILA reported 1921 dengue cases and 56 severe dengue cases in the three municipalities; of them, three died. One out of four cases occurred in rural areas. The age category most affected was adulthood, and there were no statistical differences in the number of cases between sexes. The Poisson multilevel analysis with the best fit model explained the presentation of cases were temperature, relative humidity, precipitation, childhood, live in urban area and the contributory healthcare system. The temperature had the biggest influence on the presentation of dengue cases in this region between 2010 and 2015.

Safety of a proteoliposome from Neisseria meningitides as adjuvant for a house dust mite allergy vaccine.

The proteoliposome (PL) of Neisseria meningitidis serogroup B has been reported as a safe and potent vaccine adjuvant, inducing a TH1-skewed response. The present study describes a pre-clinical safety evaluation of an allergy therapeutic vaccine candidate based on purified allergens from Dermatophagoides siboney house dust mite and PL as adjuvant, both components adsorbed onto aluminum hydroxide gel. Two separate studies of acute toxicity evaluation were performed in mice and rabbits, and two repeat-dose studies were conducted in non-sensitized and allergen-sensitized Balb/c mice, respectively. The study in sensitized mice intends to model a therapeutic setting. Aerosolized allergen challenge was used in both settings to model natural respiratory exposure. In the therapeutic setting, mice were administered with three doses containing 2 µg allergen at weekly intervals [subcutaneous route] and subsequently challenged with aerosolized allergen for 6 consecutive days. Parameters of general toxicity effects were assessed via measures of behavior, body weight, food and water consumption, and macroscopic evaluation of organs. Histological examination of organs and the injection site was performed. Potential immunotoxicity effects at the systemic level were assessed by blood eosinophil counting and serum allergen specific IgE by ELISA The vaccine did not produce general or functional toxic effects of significance, at a dose up to 100 µg allergen per kg body weight. An expected local reaction at the injection site was observed, which could be attributed mostly to the immunological effect of aluminum hydroxide. The models implemented here suggest an acceptable safety profile of this vaccine for testing in clinical trials of allergy immunotherapy.

The effect of the administration of human gamma globulins in a model of BCG infection in mice.

The effect of the administration of a commercial preparation of human gamma globulins has been evaluated in a mouse model of intranasal infection with BCG. First, we demonstrated the passage of specific antibodies to saliva and lung lavage following the intranasal or intraperitoneal administration to mice of human gamma globulins. This treatment of mice inhibited BCG colonization of the lungs (p < 0.01). A similar inhibitory effect was observed after infection of mice with gamma globulin opsonized BCG organisms (p < 0.01). These results are relevant for the development of new strategies for the control and treatment of tuberculosis.

[In silico identification of molecular mimicry between T-cell epitopes of Neisseria meningitidis B and the human proteome]. / Identificación In Silico del mimetismo molecular entre epitopes T de Neisseria meningitidis B y el proteoma humano.

The objective of the study was to determine the T-cell epitopes of four of the most frequent antigenic proteins of the outer membrane of Neisseria meningitidis B, and to identify the most relevant sites for molecular mimicry with T-cell epitopes in humans. In order to do so, an in silico study -a type of study that uses bioinformatic tools- was carried out using SWISS-PROT/TrEMBL, SYFPEITHI and FASTA databases, which helped to determine the protein sequences, CD4 and CD8 T-cell epitope prediction, as well as the molecular mimicry with humans, respectively. Molecular similarity was found in several human proteins present in different organs and tissues such as: liver, skin and epithelial tissues, brain, lymphatic system and testicles. Of these, those found in testicles were more similar, showing the highest frequency of mimetic sequences. This finding shed light on the success of N. meningitidis B to colonize human tissues and the failure of certain vaccines against this bacterium, and it even helps to explain possible autoimmune reactions associated with the infection or vaccination.

Evaluation of enteric-coated tablets as a whole cell inactivated vaccine candidate against Vibrio cholerae.

A vaccine candidate against cholera was developed in the form of oral tablets to avoid difficulties during application exhibited by current whole cell inactivated cholera vaccines. In this study, enteric-coated tablets were used to improve the protection of the active compound from gastric acidity. Tablets containing heat-killed whole cells of Vibrio cholerae strain C7258 as the active pharmaceutical compound was enteric-coated with the polymer Kollicoat(®) MAE-100P, which protected them efficiently from acidity when a disintegration test was carried out. Enzyme-linked immunosorbent assay (ELISA) anti-lipopolysaccharide (LPS) inhibition test and Western blot assay revealed the presence of V. cholerae antigens as LPS, mannose-sensitive haemagglutinin (MSHA) and outer membrane protein U (Omp U) in enteric-coated tablets. Immunogenicity studies (ELISA and vibriocidal test) carried out by intraduodenal administration in rabbits showed that the coating process of tablets did not affect the immunogenicity of V. cholerae-inactivated cells. In addition, no differences were observed in the immune response elicited by enteric-coated or uncoated tablets, particularly because the animal model and immunization route used did not allow discriminating between acid resistances of both tablets formulations in vivo. Clinical studies with volunteers will be required to elucidate this aspect, but the results suggest the possibility of using enteric-coated tablets as a final pharmaceutical product for a cholera vaccine.

Perfil neuropsicológico en un paciente con esquizofrenia / Neuropsychological profile in a patient with schizophrenia

La investigación describe el perfil neuropsicológico de un paciente con esquizofrenia en Cúcuta, Colombia. Se utilizó un diseño de investigación tipo ensayo clínico con fin diagnóstico y alcance descriptivo basado en un paciente de 52 años diagnosticado con esquizofrenia paranoide desde los 17 años, quien actualmente es tratado con antipsicótico atípico (risperidona 4,5 mg/día) y antidepresivo tricíclico (clorimipramina 300 mg/día). Se evaluó mediante un protocolo neuropsicológico conformado por Evaluación Cognitiva Montreal (MOCA, del acrónimo en inglés Montreal Cognitive Assessment), Test del Trazo (Trail Making, en inglés) A y B, subpruebas del Test Barcelona, curva de aprendizaje del Test Verbal de California, Figura Compleja de Rey­Osterrieth, y subpruebas de WAIS III, cuyas respuestas generaron indicadores globales asociados con deterioro cognitivo leve, compromiso de la capacidad de atención alternante, memoria de trabajo, conversión acústico-fonológica y memoria declarativa de largo plazo, al igual que sus funciones ejecutivas.

This research aims to describe the neuropsychological profile in a patient with schizophrenia in the city of Cucuta, Colombia. A clinical trial type research design with a diagnostic purpose and descriptive scope was used in a patient aged 52 diagnosed with paranoid schizophrenia since age 17, currently being treated with atypical antipsychotic (Risperidone 4.5 mg/day) and tricyclic antidepressants (Clomipramine 300 mg/day). A neuropsychological protocol consisting of Montreal Cognitive Assessment (MOCA), Trail Making Test A and B, subtest of Barcelona Test, learning curve of the California Verbal Learning ​​Test, Rey­Osterrieth Complex Figure Test, and WAIS III subtests, recorded global indicators associated with mild cognitive impairment, commitment in the capacity of alternating attention, working memory, acoustic-phonemic conversion, and long-term declarative memory, as well as his executive functions.

Randomized, double-blind, placebo-controlled trial to evaluate the safety and immunogenicity of live oral cholera vaccine 638 in Cuban adults.

A randomized, double-blind, placebo-controlled clinical trial was conducted to evaluate the safety, reactogenicity and the immunogenicity of a 2 x 10(9)CFU dose of the 638 lyophilized live attenuated cholera vaccine for oral administration, formulated and produced at Finlay Institute, City of Havana, Cuba. Thirty-six healthy female and male adult volunteers from 18 to 40 years old were involved, clinically examined and laboratory tested after the informed consent signature. Adverse events were monitored and seroconversion rates and geometrical mean titer (GMT) of vibriocidal antibodies were tested in volunteer's sera samples. Neither serious adverse events nor other damages to the volunteers due to vaccine or placebo feeding were reported during the clinical follow-up period of this study; none of the adverse events registered within the first 72 h after inoculation were life-threatening for volunteers. Neither severe nor moderate adverse events were reported. Sixty-one percent of subjects showed mild expected adverse events in an interval lower than 24h up to the first 72 h, 75% of these in the vaccinated group and 18% in the placebo group. Fourteen days after inoculation the GMT of vibriocidal antibodies in the vaccine group significantly increased in comparison to the placebo group. All subjects in the vaccine group (24) seroconverted (100%). Results show that this vaccine is safe, well tolerated and immunogenic in healthy female and male volunteers.

Identificación In Silico del mimetismo molecular entre Epitopes T de Neisseria meningitidis B y el proteoma humano / In Silico identification of molecular mimicry between T-Cell Epitopes of Neisseria meningitidis B and the human proteome

El objetivo del estudio fue determinar los epítopes T de cuatro de las proteínas antigénicas más frecuentes de la membrana externa de Neisseria meningitidis B e identificar los sitios más relevantes donde existe mimetismo molecular para estos epítopes en seres humanos. Para ello se realizó un estudio in silico (estudios que usan herramientas bioinformáticas) usando las bases de datos SWISS-PROT/TrEMBL SYFPEITHI y FASTA, las cuales se emplearon para la determinación de las secuencias proteicas, la predicción de los epítopes T CD4 y CD8, y la determinación del mimetismo molecular en humanos, respectivamente. Se encontró similitud molecular en varias proteínas humanas presentes en diferentes órganos y tejidos, entre ellos: hígado, piel y epitelios, cerebro, sistema linfático y testículos, destacando las encontradas en estos últimos, ya que ellas mostraron la frecuencia más alta de secuencias miméticas. Este hallazgo ayuda a comprender el éxito de N. meningitidis B para colonizar tejidos humanos, el fracaso de ciertas vacunas contra esta bacteria e incluso ayuda a explicar posibles reacciones autoimmunes asociadas a la infección o vacunación.

The objective of the study was to determine the T-cell epitopes of four of the most frequent antigenic proteins of the outer membrane of Neisseria meningitidis B, and to identify the most relevant sites for molecular mimicry with T-cell epitopes in humans. In order to do so, an in silico study -a type of study that uses bioinformatic tools- was carried out using SWISS-PROT/TrEMBL, SYFPEITHI and FASTA databases, which helped to determine the protein sequences, CD4 and CD8 T-cell epitope prediction, as well as the molecular mimicry with humans, respectively. Molecular similarity was found in several human proteins present in different organs and tissues such as: liver, skin and epithelial tissues, brain, lymphatic system and testicles. Of these, those found in testicles were more similar, showing the highest frequency of mimetic sequences. This finding shed light on the success of N. meningitidis B to colonize human tissues and the failure of certain vaccines against this bacterium, and it even helps to explain possible autoimmune reactions associated with the infection or vaccination.

Study of a Leptospirosis Outbreak in Honduras Following Hurricane Mitch and Prophylactic Protection of the vax-SPIRAL® Vaccine.

Honduras was one of the Central American countries most severely hit by Hurricane Mitch. Torrential rains and heavy flooding created conditions conducive to a leptospirosis outbreak in the country. A group of Cuban scientists studied 68 patients from the Department of Cort�s - one of the country's hardest hit areas - presenting clinical and epidemiological profiles indicative of leptospirosis. Blood and serum samples were taken from all subjects. A microscopic agglutination test (MAT) was used to identify Leptospira strains and to assess protection conferred by vax-SPIRAL® (Cuban leptospirosis vaccine) against the isolated strain. Prevalence of leptospires in the kidneys and liver was also verified. A male predominance was found in the group aged 15-49 years. Municipalities in this Department with the largest number of cases were San Pedro Sula, La Lima, and Chamelec�n. The most frequent symptoms included fever, headache, myalgia, and generalized discomfort. Over 80% of subjects reported presence of rodents in their homes, as well as contact with stagnant water and domestic animals. The strain isolated from positive blood cultures was from the Icterohaemorrhagiae serogroup, which was highly virulent in the animal model used. Protection was 100% in hamsters inoculated with vax-SPIRAL® and subsequently challenged with the Honduran strain. Additionally, macroscopic analysis of organs from immunized animals that survived the challenge showed no signs of leptospirosis infection.

New meningococcal C polysaccharide-tetanus toxoid conjugate Physico-chemical and immunological characterization.

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.

A conjugate vaccine composed of a heat shock protein 60 T-cell epitope peptide (p458) and Neisseria meningitidis type B capsular polysaccharide.

Neisseria meningitidis type B is a major world-health problem. The Meningococcus type B capsular polysaccharide (MnB) is very poorly immunogenic and no vaccine to the antigen exists. Here, we conjugated the MnB to a T-cell carrier peptide (p458) derived from the self-60kDa heat shock protein molecule. The conjugate vaccine was effective in inducing long-lasting IgG antibodies to the MnB antigen in mice. The vaccine was also immunogenic when injected in PBS. Thus, the p458 carrier peptide can induce T-cell help for the switch to IgG Ab to the MnB antigen.

Efecto inmunomodulador de la solución CM-95 tratada magnéticamente en ratones Balb/c inoculados con 5-fluorouracilo / Immunomodulator effect of the CM-95 Solution treated magnetically in Balb/c mouse with 5- fluorouracil inoculated

El 5-fluorouracilo es un antineoplásico usado en la terapia del cáncer y posee acción inmunosupresora al inhibir la proliferación de células del tejido hematopoyético. En este trabajo se evaluó el efecto inmunomodulador de la solución CM-95 tratada magnéticamente en ratones Balb/c inoculados con 5-fluorouracilo a través de su acción protectora rehabilitadora sobre parámetros celulares y tisulares del tejido hematopoyético. A los ratones, entre 20-22 g de peso y 6 semanas de nacidos, se les administró esta solución CM-95 tratada magnéticamente por vía intraperitoneal en un esquema de dos inoculaciones; luego se administró por la misma vía el 5_fluorouracilo a una dosis de 150 mg/m2 de superficie corporal de cada ratón. Se evaluó el conteo total y diferencial de leucocitos antes de inocular el 5-fluorouracilo, y a los tres y siete días de aplicado este. La celularidad de médula ósea y bazo y la observación microscópica del corte histológico de hígado y bazo por la técnica de inclusión en parafina y tinción con eosina hematoxilina al 10 por ciento se evaluaron a los siete días de haber aplicado el 5- fluorouracilo. La solución CM-95, tratada magnéticamente, logró modular los efectos del 5-fluorouracilo con una actividad protectora rehabiltadora, para los parámetros evaluados en médula ósea, sangre periférica, bazo e hígado. Estos resultados abren nuevas perspectivas para la aplicación del sistema acuoso tratado magnéticamente como inmunomodulador(AU)

5-Fluorouracil is an antineoplastic drug used in cancer chemotherapy. It has immunosuppressant effects by inhibiting cell proliferation from the haematopoietic tissue. In this paper, the immunomodulating effect of the magnetically treated CM-95 solution in Balb/c mice inoculated with 5- fluorouracil by its rehabilitating protecting action on cell parameters of the haematopoietic tissue. Six-week old mice weighing 20-22 g were inoculated twice with magnetically treated CM-95 solution by intraperitoneal route. Then, they received 5-fluoracile in a dose of 150 mg/m2 of body surface by the same route. Haematopoietic parameters such as total and differential leukocyte count were evaluated before applying the antineoplastic drug and at the third and seventh days after the application. Bone marrow and spleen cellularity as well as the microscopic observation of the histological cut of the liver and of spleen, by the technique of inclusion in paraffin dyes with 10 percent eosin haematoxylin, were evaluated at seven days after the application of 5 fluorouracil. The magnetically treated CM-95 solution could modulate the effects of 5-fluorouracil with protecting and rehabilitating activity for the parameters evaluated in the bone marrow, peripheral blood, spleen and liver. These results open new perspectives for the application of the magnetically treated aqueous system as immunomodulator(AU)

Comparación de dos estrategias para la enseñanza de un módulo de entrevista clínica en estudiantes de pregrado de medicina / Comparison of two strategies for the teaching of a clinical interview module in undergraduate medical students

Introducción: Los cambios en la práctica médica limitan la disponibilidad de pacientes y han generado escenarios de enseñanza de la medicina cada vez más escasos. Por ello se ha hecho necesario desarrollar métodos multimedia en la educación médica. Materiales y métodos: Se diseñó un ensayo controlado, abierto, no aleatorizado para comparar dos métodos de enseñanza: clase magistral y una herramienta multimedia, dentro del proceso de enseñanza de un módulo de entrevista clínica en estudiantes de pregrado de medicina de una universidad pública y una privada. Resultados: 268 estudiantes, 156 que recibieron clase magistral y 112 que recibieron el material multimedia, participaron en el estudio. El promedio de las calificaciones obtenidas en la evaluación por los estudiantes que usaron el material multimedia fue significativamente más alto que quienes tomaron la clase magistral. Además, aprobar u obtener una calificación igual o mayor a 3,5 fue aproximadamente dos veces mayor en los que usaron la herramienta multimedia que en los que asistieron a clase. Conclusiones: La multimedia es una herramienta útil y eficiente para la enseñanza de la entrevista a estudiantes de medicina...

Introduction: Changes in medical practice have limited the availability of patients and scenarios for medical education, resulting in the need to develop multimedia tools for this purpose. Methods: This is a controlled, open, nonrandomized study comparing two teaching methods: Lecture vs. a multimedia tool, in the process of teaching a clinical interview module to undergraduate medical students from a public and a private universities. Results: 268 students participated in the study, 156 received a standard lecture and 112 multimedia material. The average scores on the examinations of students using the multimedia material were significantly higher than those who took the standard lecture. Approximately twice as many of the students using the multimedia tool obtained a passing score of 3.5 or higher when compared to those who attended the lecture. Conclusions: Multimedia is a useful and efficient tool for teaching the clinical interview to medical students...

Development and characterization of murine monoclonal antibody specific for the P1,4 Por A proteins from strain B: 4: P1,(7b),4, of Neisseria meningitidis / s. t

Neisseria meningitidis isolates are conventionally classified by serosubtyping that characterizes the reactivities of the PorA outer membrane protein variable-region epitopes with monoclonal antibodies. Porins are outer membrane proteins (OMPs) of N. meningitidis serogroup B and have attracted study principally for two reasons: their use in the classification of meningococcal isolates into serotype and subtype and as potential components of vaccines against this important pathogen. New murine hybridomas, secreting specific monoclonal antibodies against PorA serotype P1.4 of N. meningitidis serogroup B, were generated using conventional hybridoma procedures. The monoclonal antibodies obtained were characterized by Western blot and whole cell ELISA, using reference strains from different N. meningitidis serotypes and subtypes. All monoclonal antibodies belong to isotype IgG1. Others hybridomas producing MAbs against PorB and FrpB were also obtained(AU)

Los aislamientos de Neisseria meningitidis se clasifican convencionalmente por serosubtipos. Su reactividad se realiza entre el epítope de la región variable de la proteína de membrana externa PorA con anticuerpos monoclonales. Las porinas, proteínas de membrana externa de N. meningitidis del serogrupo B, son atractivas para su estudio principalmente por la clasificación en serotipo y subtipo de los aislamientos del meningococo y como posibles componentes de vacunas contra este importante agente patógeno. Se generaron nuevos hibridomas murinos secretores de anticuerpos monoclonales específicos contra la proteína PorA subtipo P1.4 de N. meningitidis del serogrupo B, mediante los procedimientos convencionales de hibridomas. Los anticuerpos monoclonales, pertenecientes al isotipo IgG1, fueron caracterizados mediante Western blot y ELISA de células enteras. Se utilizaron cepas de referencia de diferentes serotipos y subtipos de N. meningitidis y se obtuvieron hibridomas productores de anticuerpos monoclonales contra otras proteínas como PorB y FrpB(AU)

Bacterial derived proteoliposome for allergy vaccines.

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.

New method for obtaining conjugated vaccines.

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.

Proteliposome-derived Cochleate as an immunomodulator for nasal vaccine.

Proteoliposome (PL) has been recently used as a protective intramuscular (i.m.) anti-meningococcal BC vaccine. It induces a preferential Th 1 type of immune response. Nevertheless, mucosal protection is mainly mediated by IgA antibody response, which is not usually induced by i.m. vaccination route. IgA antibody production needs the stimulation of Th3 subpopulation, which is also related to the induction of small dose tolerance. We hypothesized that PL-derived Cochleate can induce a specific mucosal IgA and systemic IgG antibody responses. We could show that mice immunized with two or three intranasal doses of PL-derived Cochleate developed significantly increased levels of local anti PL IgA and systemic IgG antibody responses. Thus, our results suggest that PL-derived Cochleate can be used as a promising immunomodulator and delivery system for the development of mucosal, particularly nasal vaccines.

Portadores nasofaríngeos de Neisseria meningitidis en trabajadores con riesgo ocupacional / Nasopharyngeal carriers of Neisseria meningitidis in workers with occupational risk

Los portadores de Neisseria meningitidis constituyen la principal fuente de infección y transmisión de la enfermedad meningocócica. Conocer su prevalencia, las características de las cepas aisladas y los factores de riesgos asociados con el estado de portador, aportan datos valiosos al control y vigilancia epidemiológica de esta entidad clínica. Para cumplimentar los objetivos propuestos se realizó un estudio transversal descriptivo de portadores de N meningitidis en 112 trabajadores de un centro de producción de biofarmacéuticos de La Habana, con edades comprendidas entre 18_60 años. Previo a su realización se cumplió con las exigencias bioéticas requeridas para este tipo de estudio. A todos se les realizó un exudado nasofaríngeo y una encuesta, donde se indagó sobre factores de riesgo (edad, sexo, hacinamiento, hàbito de fumar, consumo de bebidas alcohólicas, amigdalectomía y antecedentes de infección respiratoria) que favorecen la condición del portador. La identificación de las cepas de N meningitidis se realizó según métodos convencionales, la clasificación de los serogrupos se hizo por aglutinación en làminas portaobjetos con antisueros comerciales y para la identificación de los serotipos y subtipos se empleó un ensayo inmunoenzimàtico (ELISA) de células enteras con anticuerpos monoclonales. Se detectó un 8 por ciento de portadores de N meningitidis con predominio del serogrupo B (77,8 por ciento) y el fenotipo màs frecuente fue el B:4:P1.4 (33,3 por ciento). Al analizar el estado de portador y su asociación con los factores de riesgo, la edad (p = 0,05) y el sexo (p = 0,013) mostraron diferencias significativas. Se demostró la posibilidad del riesgo ocupacional en aquellos individuos que por su profesión estàn en contacto con microorganismos patógenos(AU)

Neisseria meningitidis carriers are the main infection and transmission source of the meningococcal disease. To know their prevalence, the characteristics of isolated strains and the risk factors associated to carrier status, provide important information for epidemiological surveillance and control. A descriptive-transversal study on N. meningitidis carriers was performed. It involved 112 workers from a biopharmaceutical production center in Havana, from 18 to 60 years old. Bioethical requirements were complied before starting the study. A nasopharyngeal swab was performed to all subjects and they were surveyed to find out on risk factors (age, sex, overcrowding, smoking and drinking habit, amygdalectomy and background of respiratory infection) that may favor the condition of the carrier. The identification of N meningitidis strains was carried out using conventional methods, the classification of the serogroups by slide agglutination with commercial antisera and the identification of serotypes and subtypes by an immunoenzymatic assay (ELISA) of whole cells with monoclonal antibodies. Eight percent of N meningitidis carriers was detected, serogroup B (77.8 percent) was predominant and B:4:P1.4 (33.3 percent) was the most frequently observed phenotype. When analyzing the carrier status and its association to risk factors, statistically significant difference was only observed in age (p=0.05) and sex (p= 0.013). The possibility of occupational risk was demonstrated in those subjects, who due to their profession are involved with pathogenic microorganisms(AU)

Evaluación del potencial de Mycobacterium smegmatis como candidato vacunal contra la tuberculosis mediante estudios in sílico e in vivo / Evaluation of the potential of Mycobacterium smegmatis as vaccine Candidate against tuberculosis by in silico and in vivo studies

In this study, we scanned multiple published databases of gene expression in vivo of M tuberculosis at different phases of infection in animals and humans, to select 38 proteins that are highly expressed in the active, latent and reactivation phases. The selected proteins were predicted for T and B epitopes. For each proteins, the regions containing T and B epitopes were selected at the same time to look for identical epitopes on M smegmatis based on sequence alignments. Preliminary studies of humoral immunogenicity and cross-reactivity with M tuberculosis in mice using two M smegmatis-derived experimental vaccines were carried out, demonstrating the immunogenicity of M smegmatis proteoliposomes and the recognition of M tuberculosis proteins by the sera of animals immunized with this vaccine candidate. The conjunction of in silico and in vivo studies suggested the potential for future evaluation of M smegmatis as vaccine candidate against tuberculosis using different strategies.(AU)

En este estudio se revisaron múltiples bases de datos publicadas, relacionadas con experimentos de expresión de genes de M tuberculosis in vivo en diferentes estadios de la infeccción en humanos y animales. Se identificaron 38 proteínas con elevada expresión en las fases activa, latente y de reactivación de la infección. Se llevó a cabo la predicción de epítopes T y B en dichas proteínas. Las regiones de cada proteína que contenían simultàneamente epítopes T y B se seleccionaron y utilizaron para identificar regiones idénticas en M smegmatis mediante el alineamiento de secuencias. Se llevaron a cabo estudios de inmunogenicidad humoral y reactividad cruzada con M tuberculosis en ratones inmunizados con dos vacunas experimentales obtenidas a partir de M smegmatis, demostràndose la immunogenicidad de los proteoliposomas y el reconocimiento de proteínas de M tuberculosis por el suero de ratones vacunados con este candidato vacunal. Los resultados obtenidos con los estudios in sílico e in vivo sugieren la potencialidad para evaluación futura de candidatos vacunales obtenidos a partir de M smegmatis para la prevención de la tuberculosis(AU)