Mycobacterium bovis BCG expressing the proteins CP40 or CP09720 of Corynebacterium pseudotuberculosis promotes protection in mice after challenge.

In this study, we assessed the survival and immune response of mice vaccinated with recombinant Mycobacterium bovis BCG Pasteur that expressed the CP40 or CP09720 proteins after the mice were challenged with a C. pseudotuberculosis MIC-6 virulent strain. Six groups of mice (n = 10 mice per group) were immunised with a sterile 0.9% saline solution (G1), 106 CFU of M. bovis BCG Pasteur (G2), 106 CFU of M. bovis BCG/cp40 (G3), 106 CFU of M. bovis BCG/cp09720 (G4), M. bovis BCG/cp40 boosted with rCP40 (G5), and M. bovis BCG/cp09720 boosted with rCP09720 (G6). The highest survival rate of 90% was observed in the G5 group, followed by 80% in the G6 group and 70% in the G3 and G4 groups. Moreover, a significantly greater induction of IFN-γ and IL-10 was found in the G3 group and higher IL-17 levels were recorded in the G5 group compared to their levels in the control group (G1) (p < 0.05). A specific humoral immune response (total IgG) was found in the G5 and G6 groups on day 42 compared to the level of response in the G1 group. These results indicated that the vector vaccine elicited significantly greater survival of mice in all experimental groups after a strong virulent challenge and induced a strong immune response.

[Evaluation of technological development in health from the occurrence of the zika and chikungunya epidemics in Brazil]. / Avaliação do desenvolvimento tecnológico em saúde a partir da ocorrência das epidemias de zika e chikungunya no Brasil.

This study aims to understand how the zika and chikungunya epidemics incited technological development. We surveyed epidemiological data and technological prospecting, using data from Brazilian National Institute of Industry Property (INPI) and Orbit Intelligence, and analyzed products developed/under development worldwide and products registered in Brazil by Brazilian Health Regulatory Agency (Anvisa). In 2016, the highest number of total cases was observed for both diseases. Brazil's technological prospection revealed the existence of a global interest in developing technologies for these diseases and filing their patents in Brazil, with companies as the main depositors. Global technological prospecting showed that 2016 is an important milestone in the evolution of the number of patents for zika and chikungunya, suggesting that Brazilian epidemics stimulated the world in the development of new health inputs. The United States and China are the main jurisdictions, with universities as the largest depositors. Global product analysis revealed that only two products reached the market for zika and one for chikungunya, and vaccines are in the top category. A research in Anvisa revealed more products registered for zika compared to chikungunya. The main legal manufacturers are Brazilian companies, with DiaSorin S.p.A., Eco Diagnóstica Ltda., and Chembio Diagnostics Brazil Ltda. leading the registration requests. Despite the visible stimulus to research, development, and patenting generated by the zika and chikungunya epidemics in Brazil, such stimulus did not guarantee the arrival of new products on the market and population access to these products.

Buscando compreender como as epidemias de zika e chikungunya incitaram o desenvolvimento tecnológico, este estudo realizou levantamento de dados epidemiológicos e prospecção tecnológica, utilizando dados do Instituto Nacional da Propriedade Industrial (INPI) e do Orbit Intelligence. Ainda, analisou produtos desenvolvidos e em desenvolvimento a nível mundial e aqueles registrados no Brasil por meio da Agência Nacional de Vigilância Sanitária (Anvisa). No ano de 2016, observou-se o maior número de casos totais para ambas as doenças. A prospecção tecnológica nacional revelou que há interesse global em desenvolver tecnologias para essas doenças e depositar suas patentes no Brasil, tendo as empresas como principais depositantes. Por sua vez, a prospecção tecnológica global mostrou que o ano de 2016 configura-se como importante marco na evolução do número de patentes para zika e chikungunya, sugerindo que as epidemias brasileiras estimularam o mundo no desenvolvimento de novos insumos para a saúde. Os Estados Unidos e a China são as principais jurisdições, tendo as universidades como maiores depositantes. A análise de produtos a nível global revelou que apenas dois chegaram ao mercado para zika e um para chikungunya, e as vacinas estão na categoria principal. A busca na Anvisa revelou que há mais produtos registrados para zika do que em comparação à chikungunya. Os principais fabricantes legais são empresas brasileiras, com pedidos de registro realizados principalmente pelas empresas DiaSorin S.p.A., ECO Diagnóstica Ltda. e Chembio Diagnostics Brazil Ltda. Apesar do visível estímulo à pesquisa, desenvolvimento e patenteamento gerado pelas epidemias de zika e chikungunya no Brasil, isso não garantiu a chegada de novos produtos ao mercado nem acesso da população a eles.

Con el fin de comprender cómo las epidemias de zika y chikunguña estimularon el desarrollo tecnológico, este estudio realizó la recopilación de datos epidemiológicos y la prospección tecnológica, utilizando datos del Instituto Nacional de la Propiedad Industrial (INPI) y Orbit Intelligence, y analizó los productos desarrollados y en desarrollo en todo el mundo y productos registrados en Brasil por la Agencia Nacional de Vigilancia Sanitaria (Anvisa). En 2016 se observó el mayor número de casos para ambas enfermedades. La prospección tecnológica nacional reveló que existe un interés mundial por desarrollar tecnologías para estas enfermedades y depositar sus patentes en Brasil, con las empresas como los principales depositantes. La prospección tecnológica mundial mostró que 2016 fue un hito importante en la evolución del número de patentes de zika y chikunguña, lo que sugiere que las epidemias brasileñas estimularon el desarrollo mundial de nuevos insumos para la salud. EE.UU. y China son las principales jurisdicciones, con las universidades como las mayores depositantes. El análisis global de productos reveló que solo 2 han llegado al mercado para zika y 1 para chikunguña, y las vacunas están en la categoría superior. La búsqueda en Anvisa reveló la existencia de más productos registrados para zika que para chikunguña. Los principales fabricantes legales son empresas brasileñas, con las solicitudes de registro realizadas principalmente por DiaSorin S.p.A., Eco Diagnóstica Ltda. y Chembio Diagnostics Brazil Ltda. Aunque hubo una notable promoción a la investigación, desarrollo y patentamiento generado por las epidemias de zika y chikunguña en Brasil, esto no implicó la llegada de nuevos productos al mercado y el acceso a ellos por parte de la población.

Avaliação do desenvolvimento tecnológico em saúde a partir da ocorrência das epidemias de zika e chikungunya no Brasil / Evaluation of technological development in health from the occurrence of the zika and chikungunya epidemics in Brazil / Evaluación del desarrollo tecnológico en salud desde la ocurrencia de las epidemias de zika y chikunguña en Brasil

Buscando compreender como as epidemias de zika e chikungunya incitaram o desenvolvimento tecnológico, este estudo realizou levantamento de dados epidemiológicos e prospecção tecnológica, utilizando dados do Instituto Nacional da Propriedade Industrial (INPI) e do Orbit Intelligence. Ainda, analisou produtos desenvolvidos e em desenvolvimento a nível mundial e aqueles registrados no Brasil por meio da Agência Nacional de Vigilância Sanitária (Anvisa). No ano de 2016, observou-se o maior número de casos totais para ambas as doenças. A prospecção tecnológica nacional revelou que há interesse global em desenvolver tecnologias para essas doenças e depositar suas patentes no Brasil, tendo as empresas como principais depositantes. Por sua vez, a prospecção tecnológica global mostrou que o ano de 2016 configura-se como importante marco na evolução do número de patentes para zika e chikungunya, sugerindo que as epidemias brasileiras estimularam o mundo no desenvolvimento de novos insumos para a saúde. Os Estados Unidos e a China são as principais jurisdições, tendo as universidades como maiores depositantes. A análise de produtos a nível global revelou que apenas dois chegaram ao mercado para zika e um para chikungunya, e as vacinas estão na categoria principal. A busca na Anvisa revelou que há mais produtos registrados para zika do que em comparação à chikungunya. Os principais fabricantes legais são empresas brasileiras, com pedidos de registro realizados principalmente pelas empresas DiaSorin S.p.A., ECO Diagnóstica Ltda. e Chembio Diagnostics Brazil Ltda. Apesar do visível estímulo à pesquisa, desenvolvimento e patenteamento gerado pelas epidemias de zika e chikungunya no Brasil, isso não garantiu a chegada de novos produtos ao mercado nem acesso da população a eles.

This study aims to understand how the zika and chikungunya epidemics incited technological development. We surveyed epidemiological data and technological prospecting, using data from Brazilian National Institute of Industry Property (INPI) and Orbit Intelligence, and analyzed products developed/under development worldwide and products registered in Brazil by Brazilian Health Regulatory Agency (Anvisa). In 2016, the highest number of total cases was observed for both diseases. Brazil's technological prospection revealed the existence of a global interest in developing technologies for these diseases and filing their patents in Brazil, with companies as the main depositors. Global technological prospecting showed that 2016 is an important milestone in the evolution of the number of patents for zika and chikungunya, suggesting that Brazilian epidemics stimulated the world in the development of new health inputs. The United States and China are the main jurisdictions, with universities as the largest depositors. Global product analysis revealed that only two products reached the market for zika and one for chikungunya, and vaccines are in the top category. A research in Anvisa revealed more products registered for zika compared to chikungunya. The main legal manufacturers are Brazilian companies, with DiaSorin S.p.A., Eco Diagnóstica Ltda., and Chembio Diagnostics Brazil Ltda. leading the registration requests. Despite the visible stimulus to research, development, and patenting generated by the zika and chikungunya epidemics in Brazil, such stimulus did not guarantee the arrival of new products on the market and population access to these products.

Con el fin de comprender cómo las epidemias de zika y chikunguña estimularon el desarrollo tecnológico, este estudio realizó la recopilación de datos epidemiológicos y la prospección tecnológica, utilizando datos del Instituto Nacional de la Propiedad Industrial (INPI) y Orbit Intelligence, y analizó los productos desarrollados y en desarrollo en todo el mundo y productos registrados en Brasil por la Agencia Nacional de Vigilancia Sanitaria (Anvisa). En 2016 se observó el mayor número de casos para ambas enfermedades. La prospección tecnológica nacional reveló que existe un interés mundial por desarrollar tecnologías para estas enfermedades y depositar sus patentes en Brasil, con las empresas como los principales depositantes. La prospección tecnológica mundial mostró que 2016 fue un hito importante en la evolución del número de patentes de zika y chikunguña, lo que sugiere que las epidemias brasileñas estimularon el desarrollo mundial de nuevos insumos para la salud. EE.UU. y China son las principales jurisdicciones, con las universidades como las mayores depositantes. El análisis global de productos reveló que solo 2 han llegado al mercado para zika y 1 para chikunguña, y las vacunas están en la categoría superior. La búsqueda en Anvisa reveló la existencia de más productos registrados para zika que para chikunguña. Los principales fabricantes legales son empresas brasileñas, con las solicitudes de registro realizadas principalmente por DiaSorin S.p.A., Eco Diagnóstica Ltda. y Chembio Diagnostics Brazil Ltda. Aunque hubo una notable promoción a la investigación, desarrollo y patentamiento generado por las epidemias de zika y chikunguña en Brasil, esto no implicó la llegada de nuevos productos al mercado y el acceso a ellos por parte de la población.

In silico analyses and design of a chimeric protein containing epitopes of SpaC, PknG, NanH, and SodC proteins for the control of caseous lymphadenitis.

Caseous lymphadenitis (CLA) is an infectious disease that affects goats and sheep causing drastic impacts on milk and meat production and is caused by Corynebacterium pseudotuberculosis. The disease can be prevented through vaccination but currently, vaccines demonstrate limited efficacy consequently leading to a need for the development of new ones. Here, we described the in silico development of a new chimeric protein constructed with epitopes identified from the sequences of the genes nanH, pknG, spaC, and sodC, previously described as potential vaccinal targets against C. pseudotuberculosis. The chimera was expressed, purified, and its immunogenicity was evaluated using sera of immunized mice. Results indicate the chimeric protein was able to stimulate antibody production. Additionally, analysis using serum from naturally infected goats showed that the protein is recognized by sera from these animals, indicating the possibility for using this chimera in new diagnostic methods. KEY POINTS: • The chimera was expressed with 52 kDa and a yield of 7 mg/L after purification. • The chimera was recognized by the sera of animals immunized with this formulation. • Chimera reacted with the serum of goats naturally infected with C. pseudotuberculosis.

Saponin-adjuvanted recombinant vaccines containing rCP00660, rCP09720 or rCP01850 proteins against Corynebacterium pseudotuberculosis infection in mice.

PURPOSE: rCP01850, rCP09729 and rCP00660 proteins from Corynebacterium pseudotuberculosis, predicted as the three best targets to be used in vaccines against Caseous Lymphadenitis in mature epitope density (MED) analysis were tested as vaccinal targets in association to saponin as adjuvant. METHODOLOGY: rCP00660, rCP09720 and rCP01850 were expressed in E. coli and purified for immunization assay. Balb/c mice were divided into five groups of sixteen animals each. G1 was injected with saline solution (0.9% NaCl), G2 with saponin, G3, G4 and G5 with, respectively, rCP00660, rCP09720 and rCP01850 added by saponin. Two doses were administered within a 21-days interval, and blood samples were collected for IgG quantification. Twenty-one days after the last immunization, ten mice in each group were challenged with virulent C. pseudotuberculosis MIC-6 strain, and mortality was recorded for 40 days. Meanwhile six mice in each group were used for cytokine quantification by qPCR. RESULTS: G2, G3, G4 and G5 presented protection rates of 10, 30, 40 and 60%, respectively. In spite of levels of total IgG were higher in G4 and G5, production of IgG2a was higher than IgG1 for G5. G3, G4 and G5 presented significant high IFN-γ levels, however, only G5 showed high TNF-α while G3 and G4 showed high IL-17. CONCLUSION: rCP01850 added by saponin was able to protect efficiently mice against C. pseudotuberculosis challenge, and to induce high IgG, IFN-γ and TNF-α levels. In spite of rCP00660 and rCP09720 had not same adequate protection levels, significant IgG, IFN-γ, and IL-17 levels and further studies aiming to improve protection rates should be conducted.

Vaccines for caseous lymphadenitis: up-to-date and forward-looking strategies.

Caseous lymphadenitis (CLA) is an infectious chronic disease responsible for economic losses in sheep and goat breeding worldwide. CLA has no effective treatment, evidencing the vaccination schedule as the best control strategy. Although some commercial vaccines have been available, none of them provides total protection, which is sometimes insufficient and does not reach the same efficiency when compared in sheep and goats. They also have questionable safety levels and side effects. In light of this, several experimental vaccines are in development in order to improve safety, reproducibility, and protective immune response against the etiologic agent of CLA, Corynebacterium pseudotuberculosis. In this review, we discussed aspects as antigen, adjuvant, routes of administration, protection level, and animal models used in CLA vaccine development, as well the challenges and future perspectives. KEY POINTS: Caseous lymphadenitis (CLA) does not have an appropriate commercial vaccine. Different experimental vaccines are in development aiming to protect against Corynebacterium pseudotuberculosis. An ideal vaccine for CLA is necessary for the disease control.

In vitro anthelmintic activity of Lippia gracilis Schauer essential oil against egg-hatching of goat gastrointestinal nematodes / Atividade anti-helmíntica in vitro do óleo essencial de Lippia gracilis Schauer contra a eclosão de nematódeos gastrintestinais de caprinos

Since drug-resistant nematodes became a common problem in sheep and goat industries, alternative methods using natural products have emerged as a viable and sustainable anthelmintic treatment option. Here, the in vitro effect of essential oil extracted from Lippia gracilis Schauer was assessed on the hatching process of nematodes recovered from naturally infected goats. Essential oil at concentrations of 0.08% (0.008 µL/mL), 0.12% (0.012 µL/mL), and 0.16% (0.016 µL/mL) was able to induce an average inhibition of 74.7, 84 and 93%, respectively. The effective concentration required to inhibit egg hatching in 50% of eggs (EC50) was 0.03452%. Therefore, essential oil of L. gracilis showed promisor in vitro anthelmintic results against egg-hatching of goat gastrointestinal nematodes.(AU)

Como os nematoides resistentes a drogas se tornaram um problema comum nas indústrias de ovinos e caprinos, métodos alternativos que utilizam produtos naturais surgiram como uma opção de tratamento anti-helmíntico viável e sustentável. Aqui, o efeito in vitro do óleo essencial extraído de Lippia gracilis Schauer foi avaliado no processo de eclosão de nematoides recuperados de caprinos naturalmente infectadas. O óleo essencial nas concentrações de 0,08% (0,008 µL/mL), 0,12% (0,012 µL/mL), e 0,16% (0,016 µL/mL)foi capaz de induzir uma inibição média de 74,7, 84 e 93%, respectivamente. A concentração efetiva necessária para inibir a eclosão de ovos em 50% dos ovos (CE50) foi de 0,03452%. Portanto, o óleo essencial de L. gracilis apresentou resultados anti-helmínticos in vitro promissores contra a eclosão de nematódeos gastrintestinais de caprinos.(AU)

The combination of Corynebacterium pseudotuberculosis recombinant proteins rPLD, rCP01850 and rCP09720 for improved detection of caseous lymphadenitis in sheep by ELISA.

Corynebacterium pseudotuberculosis is the causative agent of caseous lymphadenitis (CLA), a chronic disease of sheep and goats. Current methods for CLA diagnosis cannot identify all infected animals; therefore, the development of an improved diagnosis is essential. We evaluated recombinant phospholipase D (rPLD) protein individually or combined with rCP01850 or rCP09720 proteins for the detection of CLA in sheep. A total of 40 positive and 25 negative sera samples were analysed by ELISA using the recombinant proteins. ELISA using rPLD (E1), rPLD+rCP01850 (E2) and rPLD+rCP09720 (E3) showed 90, 92.5 and 97.5 % sensitivity and 92, 72 and 92 % specificity, respectively. The area under the receiver operating characteristic curves for E1, E2 and E3 was 0.925, 0.882 and 0.990, respectively. ELISA using rPLD +rCP09720 demonstrated the best sensitivity and specificity. Thus, the combination of these recombinant proteins in indirect ELISA has the potential for the diagnosis of CLA in sheep.

Establishment of an objective endpoint in mice model for caseous lymphadenitis vaccine trials.

For a long time, the scientific community has described the need for a continued update in practices that ensure the welfare of animals undergoing experimentation. In addition to approaches on principles of care and use of animals, there is a more current emerging concern: defining an appropriate end point in experiments that use animals for research, teaching and testing. The term "endpoint" is defined as the point at which an experimental animal's pain and/or distress is terminated, minimized, or reduced humanely. In the present study, we established an endpoint in Balb/C mice for caseous lymphadenitis vaccine trials, which can be considered as a highly important parameter since several studies are being developed to control the disease efficiently. Mice were monitored daily until the 30th day after infection with pathogenic strain of C. pseudotuberculosis MIC-6 using the most relevant parameters for the appearance of clinical signs of caseous lymphadenitis (CLA), such as abscesses, lethargy, and loss of weight and hair. The endpoint was found to be a weight loss of 0.2167 g after five days or 10% weight loss in less than five days. In conclusion, the findings reported here will help improve animal's well-being during vaccine trials for CLA and consequently represent significant contribution to animal's welfare.

Recombinant M. bovis BCG expressing the PLD protein promotes survival in mice challenged with a C. pseudotuberculosis virulent strain.

The aim of this study was to evaluate the survival of mice inoculated with M. bovis BCG Pasteur recombinant expressing the PLD protein and challenged with a C. pseudotuberculosis virulent strain. Four groups were immunized with a sterile 0.9% saline solution (G1), 106 CFU of M. bovis BCG Pasteur (G2), 106 CFU of M. bovis BCG/pld (G3) or 106 CFU of M. bovis BCG/pld with a booster with rPLD (G4) and challenged with 104 CFU of C. pseudotuberculosis MIC-6 strain. The highest survival rate of 88% was observed in G4, followed by 77% in G3 and 66% in G2. A significant statistical difference was observed in the levels of cytokines IFN-γ and IL-10 in vaccinated groups (G3 and G4) when compared with the control group (G1) (p < 0.05). The results seem promising as the recombinant vaccine elicited a cellular immune response and provided significant survival after a high virulent challenge.

Detection of Trypanosoma vivax DNA in semen from experimentally infected goats.

The present work aimed to investigate the presence of T. vivax DNA in the semen of experimentally infected goats. Twelve male goats native to the Brazilian Northeast, adults, were randomly assigned to two experimental groups: the infected group consisting of six goats infected intravenously with 0.5 mL of blood containing approximately 1.25 × 105 trypomastigotes of T. vivax, and a control group composed of six uninfected goats. After the infection, clinical examinations aiming to evaluate rectal temperature, parasitemia and hematocrit were performed. Semen samples were collected from goats by electroejaculation on the 7th, 14th and 21st days post-infection (dpi). The recombinant DNA-encoding gene encoding the L-like-specific gene for T. vivax. The infection was characterized by increased rectal temperature, high parasitemia and significant reduction of hematocrit values. Results for T. vivax DNA detection using TviCatL-PCR were positive in all semen samples from the infected group collected on 7th, 14th and 21st dpi. The presence of T. vivax DNA in 7th dpi suggests the early invasion of the parasite in the reproductive organs. Also, the finding of T. vivax DNA in all periods analyzed may suggest the continued elimination of the parasite in the semen, which may increase the chances of sexual transmission. Thus, T. vivax DNA is recorded for the first time in the semen of infected goats. Thus, these data are of great importance, since the detection of the T. vivax genetic material in the semen may point to the possibility that the parasite may be transmitted through the sexual pathway.

Chemical composition, immunostimulatory, cytotoxic and antiparasitic activities of the essential oil from Brazilian red propolis.

Most studies of Brazilian red propolis have explored the composition and biological properties of its ethanolic extracts. In this work, we chemically extracted and characterized the essential oil of Brazilian red propolis (EOP) and assessed its adjuvant, antiparasitic and cytotoxic activities. The chemical composition of EOP was analyzed using gas chromatography with mass spectrometry (GC-MS). EOP was tested for in vitro activity against Trichomonas vaginalis (ATCC 30236 isolate); trophozoites were treated with different concentrations of EOP (ranging from 25 to 500 µg/mL) in order to establish the MIC and IC50 values. A cytotoxicity assay was performed in CHO-K1 cells submitted to different EOP concentrations. BALB/c mice were used to test the adjuvant effect of EOP. The animals were divided in 3 groups and inoculated as follows: 0.4 ng/kg BW EOP (G1); 50 µg of rCP40 protein (G2); or a combination of 0.4 ng/kg BW EOP and 50 µg of rCP40 (G3). Total IgG, IgG1 and IgG2a levels were assessed by ELISA. The major constituent compounds of EOP were methyl eugenol (13.1%), (E)-ß-farnesene (2.50%), and δ-amorphene (2.3%). Exposure to EOP inhibited the growth of T. vaginalis, with an IC50 value of 100 µg/mL of EOP. An EOP concentration of 500 µg/mL was able to kill 100% of the T. vaginalis trophozoites. The EOP kinetic growth curve showed a 36% decrease in trophozoite growth after a 12 h exposure to 500 µg/mL of EOP, while complete parasite death was induced at 24 h. With regard to CHO-K1 cells, the CC50 was 266 µg/mL, and 92% cytotoxicity was observed after exposure to 500 µg/mL of EOP. Otherwise, a concentration of 200 µg/mL of EOP was able to reduce parasite proliferation by 70% and was not cytotoxic to CHO-K1 cells. As an adjuvant, a synergistic effect was observed when EOP was combined with the rCP40 protein (G3) in comparison to the administration of each component alone (G1 and G2), resulting in higher concentrations of IgG, IgG1 and IgG2a. EOP is constituted by biologically active components with promising antiparasitic and immunostimulatory activities and can be investigated for the formulation of new vaccines or trichomonacidal drugs.

Association of Corynebacterium pseudotuberculosis recombinant proteins rCP09720 or rCP01850 with rPLD as immunogens in caseous lymphadenitis immunoprophylaxis.

Caseous lymphadenitis (CLA) is a chronic disease responsible for significant economic losses in sheep and goat breeding worldwide. The treatment for this disease is not effective, and an intense vaccination schedule would be the best control strategy. In this study, we evaluated the associations of rCP09720 or rCP01850 proteins from Corynebacterium pseudotuberculosis with recombinant exotoxin phospholipase D (rPLD) as subunit vaccines in mice. Four experimental groups (10 animals each) were immunized with a sterile 0.9% saline solution (G1), rPLD (G2), rPLD + rCP09720 (G3), and rPLD + rCP01850 (G4). The mice received two doses of each vaccine at a 21-day interval and were challenged 21 days after the last immunization. The animals were evaluated daily for 40 days after the challenge, and mortality rate was recorded. The total IgG production level increased significantly in the experimental groups on day 42 after the first vaccination. Similarly, higher levels of specific IgG2a were observed in experimental groups G2, G3, and G4 compared to the IgG1 levels on day 42. G4 showed a significant (p < .05) humoral response against both antigens of the antigenic formulations. The cellular immune response induced by immunization was characterized by a significant (p < .05) production of interferon-γ compared to that in the control, while the concentrations of interleukin (IL)-4 and IL-12 were not significant in any group. A significant increase of tumor necrosis factor was observed only in G4. The survival rates after the challenge were 30% (rPLD), 40% (rPLD + rCP09720), and 50% (rPLD + rCP01850). Thus, the association of rCP01850 with rPLD resulted in the best protection against the challenge with C. pseudotuberculosis and induced a more intense type 1 T-helper cell immune response.

Antiparasitic activity of 1,3-dioxolanes containing tellurium in Trichomonas vaginalis.

The increased prevalence of metronidazole-resistant infections has resulted in a search for alternative drugs for the treatment of trichomoniasis. In the present study, we report the preparation and in vitro activity of three 1,3-dioxolanes that contain tellurium (PTeDOX 01, PTeDOX 02, and PTeDOX 03) against Trichomonas vaginalis. Six concentrations of these compounds were analyzed for in vitro activity against ATCC 30236 isolate of T. vaginalis. PTeDOX 01 reported a cytotoxic effect against 100% of T. vaginalis trophozoites at a final concentration of 90µM with an IC50 of 60µM. The kinetic growth curve of trophozoites indicated that PTeDOX 01 reduced the growth by 22% at a concentration of 90µM after an exposure of 12h, and induced complete parasite death at 24h. It induced cytotoxicity of 44% at 90µM concentration but and had no effect in lower concentrations in a culture of CHO-K1 cells. These results confirmed that PTeDOX 01 is an important drug for the treatment of T. vaginalis, and should be evaluated in other infectious agents as well.