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Beta-barrel type proteins play an important role in both, human and veterinary medicine. In particular, their localization on the bacterial surface, and their involvement in virulence mechanisms of pathogens, have turned them into an interesting target in studies to search for vaccine candidates. Recently, Freeman and Wimley developed a prediction algorithm based on the physicochemical properties of transmembrane beta-barrels proteins (TMBBs). Based on that algorithm, and using Grails, a web-based application was implemented. This system, named Beta Predictor, is capable of processing from one protein sequence to complete predicted proteomes up to 10000 proteins with a runtime of about 0.019 seconds per 500-residue protein, and it allows graphical analyses for each protein. The application was evaluated with a validation set of 535 non-redundant proteins, 102 TMBBs and 433 non-TMBBs. The sensitivity, specificity, Matthews correlation coefficient, positive predictive value and accuracy were calculated, being 85.29%, 95.15%, 78.72%, 80.56% and 93.27%, respectively. The performance of this system was compared with TMBBs predictors, BOMP and TMBHunt, using the same validation set. Taking into account the order mentioned above, the following results were obtained: 76.47%, 99.31%, 83.05%, 96.30% and 94.95% for BOMP, and 78.43%, 92.38%, 67.90%, 70.17% and 89.78% for TMBHunt. Beta Predictor was outperformed by BOMP but the latter showed better behavior than TMBHunt. [ABSTRACT FROM AUTHOR]

Despite efforts to eradicate tuberculosis (TB) worldwide, this remains a serious health problem. The Bacillus Calmette-Guerin (BCG), the only available vaccine against TB, has variable efficacy and though protects against severe forms of the disease in childhood, has a questionable role in the protection against pulmonary tuberculosis in adults. In recent years, new TB vaccine candidates are being developed using multiple vaccine strategies. Taking into account the antigenic similarity of M. bovis BCG and M. tuberculosis, and the history of the use of proteoliposomes in vaccine formulations, we aimed to study the potentialities of a proteoliposome derived from M. bovis BCG (PLBCG) as a potential vaccine candidate against TB. The results demonstrate that a PLBCG was obtained, which was observed by different techniques and that is composed of nanoparticulate vesicles. Additionally, analysis by SDS-PAGE followed by Coomassie stained showed the presence of several protein bands on PLBCG whose molecular size may correspond with that reported for M. bovis BCG protein having homology to M. tuberculosis. [ABSTRACT FROM AUTHOR]

A double sandwich immunoassay was validated to quantify antibody protein impurities from host strain that can be present in the active pharmaceutical ingredient of Cuban vaccine against hepatitis B. All biological reagents used in the ELISA were prepared and characterized. The proteins from the host strain were obtained under the same conditions as the production process of the recombinant protein until a purification or primary semipurification step. The antisera addressed against those proteins were generated in rabbits by an immunization process in cascade. For validation the parameters analyzed were: linearity, limit of detection and quantification, accuracy, range and precision. The established assay was specific, and the calculated accuracy was from 89% to 109% for all studied buffers. A parabolic fit and a working range from 0.63 to 1.25 ng/mL were demonstrated. The repeatability and intermediate precision showed variation coefficients below 10% and 20% respectively. [ABSTRACT FROM AUTHOR]

Today it is estimated that half world population can be infected by malaria and there is not an available vaccine, however, there is hope with vaccine RTS,S/AS02. For this reason, we must continue to develop computer methodologies and strategies that will allow the rational design of potentially effective vaccines. We propose a new computational approach to predict linear B-cell epitopes from the whole genome sequencing of Plasmodium falciparum 3D7, obtained from IEDB database. Those that were repeated were discarded and were grouped into blocks according to the obtained results by Redundancy and Nomad programs. Subsequently, the possible antigenic character was predicted using the programs BepiPred, BcePred and BCPred. Three potentially antigenic sequences out of the 45 predicted were obtained with this methodology, but it is not possible to say which one the most antigenic without experimental evidence. [ABSTRACT FROM AUTHOR]

Nuclear Magnetic Resonance has become the choice for structural studies, identity assays and simultaneous quantification of active pharmaceutical ingredient of different polysaccharide-based vaccine. In the last two decades, the application of quantitative Nuclear Magnetic Resonance had an increasing impact to support several quantification necessities. The technique involves experiments with several modified parameters in order to obtain spectra with quantifiable signals. The present review is supported by some recent relevant reports and it discusses several applications of NMR in carbohydrate-based vaccines. Moreover, it emphasizes and describes several parameters and applications of quantitative Nuclear Magnetic Resonance. [ABSTRACT FROM AUTHOR]

In this paper we study the conditions of adsorption chromatography on Silica gel 60 for purification of Spacer disaccharide a component of Active Pharmaceutical Ingredient (API) of QuimiHib® vaccine. For that, we made a scale down on an analytical scale that represented at 1.8% of industrial process, indicating reproducibility between two procedures in terms of packing efficiency, purity and recovery. Dynamic binding capacity of the resin Silicagel 60 by the DSE was roughly 125±0.2 mg /mL, 3.4 times the base process. The elution profile obtained, showed the possibility of collecting a unique fraction at range 195±2 and 260±2 minutes, if it is maintained a proper packing of the chromatography resin determined by asymmetry factor from 0.8 to 1.2, which ensures a recovery of 58.9±4.5% and high purity analyzed by Thin Layer Chromatography. Adjusting the adsorption conditions increases the productivity of chromatographic operation up to 3.5 fold, indicating that it is feasible in economic terms. [ABSTRACT FROM AUTHOR]

The joint administration of the anti-hepatitis B gammaglobulin and the vaccine is worldwide recommended for the prevention of perinatal transmission to children from HBsAg(+) mothers. As a preventive measure of transmission, passive-active immunization was evaluated after 3 days and at 7 and 18 months of life. Eighty-seven sera from children from HBsAg(+) mothers were studied; these sera were collected 3 days, and 7 and 18 months after birth, for a total amount of 261 samples. Newborns were administered a dose of Cuban Human Anti-hepatitis B Immunoglobulin (Ganmahep B) and a dose of the Cuban recombinant vaccine Heberbiovac-HB® before the first 12 hours after birth. Afterwards, the vaccination scheme at months 1, 2, and 12 was followed. Children were evaluated with HBsAg and anti-HBs markers. At the third day, 8.0% of the children were HBsAg(+); the 92.5% of HBsAg(-) children turned out to be seroprotected. At 7 months of age, 1.1% was HBsAg(+), seroprotection of HBsAg(-) children was 89.5%. At 18 months of age, 3.4% was HBsAg(+), with a 97.6% of protection of HBsAg(-) children. The normoprotective response was predominant at the three periods of time, with statistically significant differences in seroprotection and titers =100 UI/L. Geometric Mean Titer (GMT) values were 72.9 UI/L, 168.66 UI/ L and 175.62 UI/L, respectively, with statistical significance among them. It is suggested that the use of Ganmahep B, along with the administration of the Cuban vaccine reduces the risk of HBV perinatal transmission and this is the first study carried out in Cuba to evaluate the prophylactic efficacy within this risk group. [ABSTRACT FROM AUTHOR]

Invasive meningococcal disease constitutes a worldwide health problem. Gram negative bacteria, Neisseria meningitidis is the causal agent of this disease. Plain or conjugated polysaccharide vaccines are available against four of five serogroups responsible of more than 95% of cases in the world. Because serogroup B polysaccharide is non immunogenic, some vaccine candidates, based on outer membrane proteins have been obtained and evaluated in clinical trials. Bactericidal activity determination and ELISA IgG have been used to evaluate immune response generated by antimeningococcal vaccines. The latter has been used, as potency test, to release VAMENGOC- BC® vaccine lots, produced at Finlay Institute. As a result of the collaboration with Norwegian researchers, a vaccine candidate based on outer membrane proteins against serogroups A and W135, has been obtained and evaluated in animal models. The current work describes the standardization of an ELISA method to be used in the immune response evaluation of the bivalent vaccinal candidate. [ABSTRACT FROM AUTHOR]

Atherosclerosis represents the first cause of death in the western world. Although there are several hypothesis which explain its pathogenesis, one of the most recognized is the autoimmune hypothesis. The activation of the immunological system against different atherogenic stimulus induces a reaction which may affect the vascular endothelium with the consequent atherogenic lesion development. The design of new therapeutic strategies, among them vaccines, represents a tool with promissory result in atherosclerosis treatment. Taking into account these antecedents, in the present work it was examined the state of the art on the immunomodulation of this chronic disease. [ABSTRACT FROM AUTHOR]

Whole cell Leptospirosis vaccines have been developed and used from the 20's of last century up today, most of them are not adjuvated and do not confer a long-lasting immunity. These vaccines are mainly against different serogroups of Leptospira interrogans contained in the preparation. Though several attempts to obtain a vaccinal formulation more effective, purer, with wider spectrum and longer protection than the bacterines of inactivated whole cells have been made no vaccine with these characteristics have been registered yet. This paper deals with the obtainment of outer membrane antigens from a Cuban autochthonous strain (Strain 87, L. interrogans serovar Canicola), by a modification of the technology for the production of outer membrane vesicles, patented by researchers from Finlay institute These antigens with nanoproteoliposomic structure were formulated/adjuvated by different strategies, obtaining five preparations with cochlear structures which are nanoparticles of approximately 100 to 150 nm of length and from 15 to 30 nm of diameter. Two doses of the immunogens are inoculated in the biomodel Mesocrisetus aureatus, with an interval of six weeks. The challenge was carried out with 100.000 DL50. Results showed that the new vaccinal formulations confer protection against the homologous challenge and were able to eliminate the carrier status. This, together with the robutness of the preparation method, the higher level of purity, compared to the bacterines, and the no need of aluminium hydroxide make the formulations an alternative of interest for continuing their development. [ABSTRACT FROM AUTHOR]

The protective efficacy of current Tuberculosis vaccine (BCG) against pulmonary tuberculosis and reactivation is variable and inefficient. This is the reason of the urgent search of new prophylactic alternatives for disease control. Different strategies using Mycobacteriun tuberculosis auxotrophic mutants, recombinant BCG or non-tuberculous micobacteria are carried out taking advantage of the use of live vaccines. Experimental evidences demonstrate protection conferred by the vaccination with live, inactivated or protein fraction of Mycobacterium habana' TMC- 5135. Protection seems to be related to few virulence signs in animal models. Experimental results place M. habana' among vaccine candidates against tuberculosis meeting the condition of a "classic" vaccine to mimic natural infection as close as possible inducing strong immune protective response without causing extensive disease. [ABSTRACT FROM AUTHOR]

Saccharomyces cerevisiae has been widely used as expression system of heterologous proteins. The aim of the present work was the expression in Saccharomyces cerevisiae of a class B multiepitopic peptide from M. tuberculosis. For this purpose, the chimerical peptide named B2 was cloned in two yeast expression vectors containing galactose and cupric sulphate regulated promoters, respectively. After induction experiments, B2 expression was analyzed by SDS/PAGE and Western Blot. By Western Blot analysis B2 expression was confirmed when induction took place overnight with 100 µM of CuSO4. No expression signal took place when galactose was used as inductor. These results show that Sacchromyces cervisiae could be a good alternative host for the expression of multiepitopic peptides from M. tuberculosis. [ABSTRACT FROM AUTHOR]

At birth, the immune system is still immature, that is why newborns are susceptible to infectious diseases. Nonetheless, newborns are partially protected by maternal antibodies. For that reason, transplacental transference of antibodies against some vaccine-preventable diseases. A prospective, randomized study was carried out in 96 mothers and their newborns. Serum samples were taken from the pregnant women before delivery in Havana City hospitals during 2004 and from the newborns in the delivery room. Immunoenzimatic assays were used for the quantitative determination of tetanus and diphtheria antitoxin, antibodies to meningococcus B outer membrane proteins (OMP), antibodies to meningococus C capsular polysaccharide (CSP), and antibodies to Vi polysaccharide of Salmonella Typhi. Suitable levels of tetanus antitoxin were found in mothers and newborns. The long-term protection levels (>1 IU/mL) were shown in 92.71% of newborns, and 88.54% of their mothers. Nonreliable levels of diphtheria antitoxin (<0.1 IU/mL) were found in 54.17% and 45.83% of mothers and newborns, respectively. Antibodies to OMP above 2 µg/mL were detected in 90.63% and 96.88% of mothers and newborns, and the 38.54% and 41.67% had proper antibodies against CSP. Seroprotection rates (>1 µg/mL) against Salmonella Typhi were 5.21% and 8.33%, respectively. Most of newborns showed higher antibody levels than that of their mothers, therefore the transplacental passage of antibodies is an efficient mechanism. [ABSTRACT FROM AUTHOR]

A randomized, controlled and double-blind trial was carried out in 225 Cuban teenagers aged 13-16 to evaluate the reactogenicity and immunogenicity of a new tetanus toxoid and reduced diphtheria toxoid vaccine (Finlay Institute) with respect to IMOVAX dT adult control vaccine (Aventis Pasteur). Serum samples were taken before and 21 days after immunization. The reactogenicity of both vaccines was similar. The general and local adverse events were mild and mainly detected in the first 72 hours after vaccination. All volunteers showed protective levels of tetanus antitoxin and diphtheria antitoxin (≤0.1 IU/mL). 99.25% of subjects who received the experimental vaccine and 98.36% of control subjects showed long-term protective values of tetanus antitoxin (≤1.0 IU/mL). These diphtheria antitoxin levels were respectively detected in 81.20% and 80.33% of volunteers. The geometric mean titer values for tetanus antitoxin and diphtheria antitoxin induced after vaccination were 21.73 IU/mL and 2.55 IU/mL respectively, higher than antitoxin levels of control group: 15.55 IU/mL and 1.84 IU/mL respectively (p<0.05). [ABSTRACT FROM AUTHOR]

The epidemiological markers (sero-groups, sero-types, sub-types, immuno-types) of 429 invasive strains isolated in Cuba during 20 years (1982-2002) were investigated. Based on the behavior of the Meningococcal Disease (MD) incidence in the investigated period, the strains were distributed in two stages: epidemic and post-epidemic. The epidemic stage involved 279 strains isolated between 1982 and 1992 and the postepidemic one included 150 isolations carried out between 1993 and 2002. All of them were seeded in Mueller Hinton Agar with fetal bovine serum (5%) and incubated for 24-48 hours, 37 0C, in humid atmosphere with 5% of C02. The identification of sex, species and sero-group was performed using conventional methods; characterization of sero/sub-types and immuno-types was carried out using the immuno-enzimatic test (ELISA) of whole cells with monoclonal antibodies. Serogroup B (97,90%) prevailed in both stages: epidemic (96.77%) and post-epidemic (100%). However, sero-group C (1.43%) and non-grouping strains (1,8%) were only observed in the isolations of the epidemic stage. The other prevailing markers were: serotype 4 (86.48%), subtype P1.19,15 (78.32%), immuno-type L3,7,9 (90.2%) which showed similar figures in both periods. Phenotype B:4:P1.19,15: L3,7,9 (69,69%) prevailed, although, in the post-epidemic stage (77.34%), the percentage was higher than that of the epidemic one (65.66%) (p<0.05). A higher diversity of phenotypic associations was also observed in the strains of this period. Results obtained from this phenotypic characterization of Neisseria meningitidis strains isolated from ill persons provide valuable data to the study, prevention and succesful control of the MD in Cuba. [ABSTRACT FROM AUTHOR]

The present paper evaluates the toxicity by single dose of the diphtheria-tetanus vaccine (VA-DIFTET®) in Sprague Dawley rats. Its administration was carried out by intramuscular route because this is the one proposed for use in humans. 0.3 mL of the vaccine or its components was administered to a total of 20 animals per group (10 per each sex). These animals were daily observed and, water and food intake was measured on alternate days determining their body weight with week intervals. The anatomopathological analysis of animals was included at the end of the study. No animal died during the assay or clinical symptoms were observed either. No statistically significant differences (p>0,1) were detected regarding water-food intake and body weight. In the anatomopathological study, macrophagic granulomatous lesions were observed in the rats treated with the vaccine or placebo; this finding is characteristic of vaccines adjuvated with aluminum hydroxide. Results suggested that VA-DIFTET® is potentially innocuous when administering the single dose by intramuscular route. [ABSTRACT FROM AUTHOR]

The pre-clinical toxicity tests in single dose and repeated doses give valuable information on the safety of the product, since they include the pathological and histopathological study of important organs, as well as the evaluation of the administration route and the dosage regime. At present, Cuba is developing a polyvalent vaccine (vax-SPIRAL®) from chemically inactivated cells, with an aluminium hydroxide adjuvant. This vaccine has advantages vis a vis other vaccines, as for example, the vaccine from the former Soviet Union. The vaccination schedule for humans consists in two doses of 0.5 mL, separated by an optimal interval of six weeks. The objective of this toxicity study in Sprague Dawley rats was to determine the potential toxicity, lethality, susceptible organs and other adverse events, as well as toxicity in the inoculation site after administering one dose of the vaccine under study. The results indicated that, under the conditions of the study and according to the established criteria for evaluating the data obtained, the antileptospirosic trivalent vaccine dose did not produce toxic effects in the animal model used. The only alterations found were granuloma formations at the inoculation site. These formations have been reported as belonging to the deposit adjuvant (aluminum hydroxide), also used in the other parenteral vaccines. [ABSTRACT FROM AUTHOR]

The exhaustive characterization of all components of our vaccine (VA-MENGOC-BC®), is a very important information to the new strategies of production and the best quality of it. Recently some regulatory authorities have recommended to remove thiomersal from vaccines altogether. In this paper we propose a disadsorption method for later chromatographic analysis of vaccine samples with or without thiomersal to know the possible antigenic variation. Three vaccine batches, stored between 2-8 °C, were studied at 0 time using different variants of disadsorption. We have demonstrated that solubilisation of the aluminium hydroxide by HCl to release the native vaccine complex is not possible and that the most efficient disadsorption method for the chromatographic analysis of VA-MENGOC-BC® is the following: the precipitate obtained from 3 mL of vaccine is diluted in 2 mL of phosphate buffer 5mM, pH 7,2-7,3, and allowed stand exactly 2 hours at 4°C. Afterwards, the samples were centrifuged and the supernatant collected. With this method we have obtained a 20% disadsorption of the sample. The result is very useful for showing the advantages of new formulations. [ABSTRACT FROM AUTHOR]

Dengue Fever (DF) and Dengue Haemorragic Fever (DHF) have emerged as the most important human viral diseases transmitted by arthropod vectors. The characteristics of this disease, plus the absence of effective antiviral drugs, the increase in the number of cases, affected countries and the difficulties for vector control have made the development of dengue vaccines a public health priority. Since the middle of the past century many strategies have been explored to achieve this objective. In spite of the advances in this field, there is much research to be done in order to have available an immunogen against dengue. [ABSTRACT FROM AUTHOR]

A procedure for coating ELISA plates with vaccine antigens is described. The optimum coating concentration was that achieving the highest absorbance for the standard sera and the lowest for the negative controls and the reagent blank. Indirect ELISA is used as model. Tetanus and diphtheria toxoids, and meningococcal B outer membrane vesicle, active principle of the meningococcal vaccine VA-MENGOC-BC®, were used as capture antigens. That procedure increases sensitivity of the assays due to coating optimization. The saturation of possible free spaces was more evident with the lowest molecular weight antigens, such as diphtheria and tetanus toxoids. [ABSTRACT FROM AUTHOR]

In geographical regions where the hepatitis B virus (HBV) has high prevalence, liver cancer is the most common neoplasm. Infection control is becoming more complex because of the considerable amount of asymptomatic carriers that exist in the world now. Nevertheless, with the discovery and production of a vaccine against hepatitis B virus and its subsequent inclusion in the Expanded Program for Immunization, this situation could change, by reducing the number of new cases and carriers in the future. This should in consequence reduce the mortality by virus-caused liver carcinoma. [ABSTRACT FROM AUTHOR]

Typhoid fever is a food-born disease of high incidence in developing countries. Finlay Institute has developed an anti-typhoid vaccine based on the capsular polysaccharide Vi. Several tests have been performed to evaluate the safety of such vaccine; among them a single dose (14 days of observation) toxicity test in both sexes of OF1 mice. A unique dose of either 0,05 or 0,5 mL by intramuscular or subcutaneous routes was applied. Negative control animals (non-inoculated mice), positive control (mice inoculated with Merieux Anti-Typhoid Vaccine) and mice inoculated with phosphate-buffered saline (buffer group) were compared to those treated with the experimental Polysaccharide Vi vaccine. Antibody titers was determined by FLISA. Water and food intakes, body weight, thymus and spleen absolute and relative weights were compared by two-wav analysis of variance and the Least Significant Difference test (LSD). Values of P under 0,05 were considered statistically significant. Mean antibody titers in the vaccine and positive control groups were statistically similar; but, highly different (P<0,001) from the negative control group. Clinical and anatomopathological studies did no detect any overt sign of toxicity. Water and food intakes, body weight increases and the weight of the spleens did not show significant differences (P<0,05) among the four experimental groups. However, the spleen relative weight and the thymus relative and absolute weights evidenced statistically significant differences (P<0,05) between the vaccine and control groups (Nevertheless, the vaccine group was similar to the negative control). Results demonstrated that the experimental Polysaccharide Vi vaccine is safe for this species because no sign of toxicity was found in any of the sex after the administration of the vaccine by intramuscutar or subcutaneous routes. [ABSTRACT FROM AUTHOR]

It was carried out a comparative study about the levels of elicited antibodies in mice by three serial batches of vaccines that had been produced in the Plant of Production of the Finlay Institute with a commercial vaccine ("Typhim Vi" from the Pasteur-Merieux Laboratories), through an immunoenzymatic test (ELISA of indirect type); it was obtained as result that there was not significant statistical differences between the levels of elicited antibodies by the vaccine batches produced in the Finlay Institute and the batch of reference vaccine. It was appreciated a significant increase of the levels of antibodies at 28 days in the vaccinated mice at compare with the controls, achieving a 100% of seroconversion for each one of the evaluated batches. [ABSTRACT FROM AUTHOR]

Since 1995, in our Institute we have been working on a project to produce the typhoid Vi polysaccharide vaccine in Cuba. During the research stage we obtained all the operation and control parameters in the different steps of the process, in this way enabling its characterization and obtaining the necessary equations to define the operation and control parameters for industrial scaling-up. Similar geometrically and dynamically systems were guaranteed, thus achieving similar results for the research stage, as well as for the production one. Also, three consecutive batches of final vaccine (8001, 8002, 8003) were produced and they fulfilled the quality specifications established by the World Health Organization ( WHO ) for this product. [ABSTRACT FROM AUTHOR]