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RESUMEN Introducción: Existen más de 390 millones de personas infectadas y 20 000 muertes anualmente a causa del dengue en el mundo. El chikungunya ocasionó una larga epidemia en las Américas con más de 2 millones y medio de casos hasta el 2017. Objetivo: Identificar las características sociodemográficas y clínicas de los casos de dengue y chikungunya informados para el periodo 2014-2017 en Nariño, Colombia. Métodos: Se realizó un estudio observacional, descriptivo, de corte transversal. Se revisaron retrospectivamente las bases de datos del Instituto Departamental de Salud de Nariño y del Hospital Universitario Departamental de Nariño. Resultados: Para el periodo de estudio hubo 2 514 hospitalizaciones por dengue y 460 por chikungunya. Se identificaron 22 casos de dengue grave, con una muerte para el año 2017. La revisión de expedientes de 1 735 pacientes con información completa reveló que las manifestaciones clínicas más frecuentes para dengue fueron: fiebre (100 por ciento), cefalea (84,6 por ciento) y mialgias (83,7 por ciento), seguidos de artralgias, rash y dolor abdominal. El sexo masculino predominó en los casos de diagnóstico de dengue (56,8 por ciento) y el femenino en el diagnóstico de chikungunya (52,0 por ciento. Tanto dengue como chikungunya fueron más frecuentes en la población mayor de 40 años con el 24,5 por ciento y 27,2 por ciento, respectivamente. Conclusiones: La sintomatología similar y los casos complicados resaltan la necesidad de contar con diagnósticos oportunos y diferenciales y capacitación al personal de salud, apoyados por entidades gubernamentales. Se requiere generar programas de intervención enfocados a edades productivas y en regiones con condiciones medioambientales propicias para el desarrollo de vectores transmisores de enfermedades(AU)
Introduction: More than 390 million dengue cases and 20 000 deaths due to this condition are reported worldwide every year. Chikungunya caused a large epidemic in the Americas with more than two and a half million cases until the year 2017. Objective: Identify the clinical and socio-demographic characteristics of the dengue and chikungunya cases reported for the period 2014-2017 in Nariño, Colombia. Methods: A cross-sectional observational descriptive study was conducted. A retrospective review was carried out of the databases at Nariño Departmental Health Institute and Nariño Departmental University Hospital. Results: During the study period there were 2 514 hospital admissions with dengue and 460 with chikungunya. A total 22 severe dengue cases and one death were identified for the year 2017. Review of the medical records of 1 735 patients with complete information revealed that the most common clinical manifestations of dengue were fever (100 percent), headache (84.6 percent) and myalgia (83.7 percent), followed by arthralgia, rash and abdominal pain. A predominance was found of the male sex in dengue cases (56.8 percent) and of the female sex in chikungunya cases (52.0 percent). Both conditions were more frequent in the population aged over 40 years, with 24.5 percent and 27.2 percent, respectively. Conclusions: The similar symptoms and the presence of complicated cases highlight the need for timely differential diagnosis and the training of the health personnel, with the support of government agencies. It is required to develop intervention programs aimed at working ages and regions with environmental conditions favorable for the spread of disease(AU)
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Humanos , Masculino , Femenino , Dengue/diagnóstico , Fiebre Chikungunya/diagnóstico , Colombia/epidemiologíaRESUMEN
BACKGROUND: Fasciolosis remains a significant food-borne trematode disease causing high morbidity around the world and affecting grazing animals and humans. A deeper understanding concerning the molecular mechanisms by which Fasciola hepatica infection occurs, as well as the molecular basis involved in acquiring protection is extremely important when designing and selecting new vaccine candidates. The present study provides a first report of microarray-based technology for describing changes in the splenic gene expression profile for mice immunised with a highly effective, protection-inducing, multi-epitope, subunit-based, chemically-synthesised vaccine candidate against F. hepatica. METHODS: The mice were immunised with synthetic peptides containing B- and T-cell epitopes, which are derived from F. hepatica cathepsin B and amoebapore proteins, as novel vaccine candidates against F. hepatica formulated in an adjuvant adaptation vaccination system; they were experimentally challenged with F. hepatica metacercariae. Spleen RNA from mice immunised with the highest protection-inducing synthetic peptides was isolated, amplified and labelled using Affymetrix standardised protocols. Data was then background corrected, normalised and the expression signal was calculated. The Ingenuity Pathway Analysis tool was then used for analysing differentially expressed gene identifiers for annotating bio-functions and constructing and visualising molecular interaction networks. RESULTS: Mice immunised with a combination of three peptides containing T-cell epitopes induced high protection against experimental challenge according to survival rates and hepatic damage scores. It also induced differential expression of 820 genes, 168 genes being up-regulated and 652 genes being down-regulated, p value <0.05, fold change ranging from -2.944 to 7.632. A functional study of these genes revealed changes in the pathways related to nitric oxide and reactive oxygen species production, Interleukin-12 signalling and production in macrophages and Interleukin-8 signalling with up-regulation of S100 calcium-binding protein A8, Matrix metallopeptidase 9 and CXC chemokine receptor 2 genes. CONCLUSION: The data obtained in the present study provided us with a more comprehensive overview concerning the possible molecular pathways implied in inducing protection against F. hepatica in a murine model, which could be useful for evaluating future vaccine candidates.
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Fasciola hepatica/inmunología , Fascioliasis/prevención & control , Expresión Génica/efectos de los fármacos , Vacunas Antiprotozoos/farmacología , Bazo/efectos de los fármacos , Animales , Anticuerpos Antihelmínticos/inmunología , Calgranulina A/efectos de los fármacos , Calgranulina A/genética , Epítopos/inmunología , Femenino , Perfilación de la Expresión Génica , Interleucina-12/genética , Interleucina-8/efectos de los fármacos , Interleucina-8/genética , Metaloproteinasa 9 de la Matriz/efectos de los fármacos , Metaloproteinasa 9 de la Matriz/genética , Ratones , Péptidos/inmunología , ARN Mensajero/efectos de los fármacos , ARN Mensajero/metabolismo , Receptores de Interleucina-8B/efectos de los fármacos , Receptores de Interleucina-8B/genética , Bazo/metabolismo , Regulación hacia Arriba , VacunaciónRESUMEN
Strongyloidiasis is widely distributed in the tropical and subtropical areas. Ivermectin is the drug of choice for the treatment. However, the concerns about relying treatment on a single drug make identification of new molecules a priority. Alkylphospholipid analogues, including edelfosine, are a group of synthetic compounds that have shown activity against some parasites. The objective was to assess the in vitro and in vivo activity of edelfosine, miltefosine, perifosine against Strongyloides venezuelensis. Moreover, apoptosis-like mechanism in larvae after treatment was studied. Edelfosine displayed the highest activity and the best selectivity index (LD50=49.6 ± 5.4µM, SI=1.1) compared to miltefosine or perifosine. Third stage larvae after culture with edelfosine were not able to develop an infection in mice. Treatment of mice with edelfosine showed reduction of 47% in parasitic females allocated in the gut. Moreover, DNA fragmentation was observed by TUNEL staining in larvae treated with edelfosine. These results suggest that edelfosine could be an effective drug against strongyloidiasis, probably through induction of apoptosis-like cell death.
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Antineoplásicos/farmacología , Apoptosis/efectos de los fármacos , Éteres Fosfolípidos/farmacología , Strongyloides/efectos de los fármacos , Animales , Relación Dosis-Respuesta a Droga , Femenino , Larva/efectos de los fármacos , Ratones , Fosforilcolina/análogos & derivados , Fosforilcolina/farmacología , Estrongiloidiasis/parasitologíaRESUMEN
BACKGROUND: Strongyloidiasis is a parasitic disease widely present in tropical and subtropical areas. Strongyloides stercoralis represents the main species that infects human beings. Ivermectin is the current drug of choice; however, issues related with treatment failure in patients with diabetes or infected with T-lymphotropic virus-1 make the identification of new molecules for alternative treatment a priority. In the present study, the activity of sphingosine-related aminoalcohol and diamine were evaluated against Strongyloides venezuelensis third-stage larva (L3) cultures and experimental infections in mice. METHODS: The efficacy of each compound against L3 was assessed using both XTT (2,3-bis-(2-methoxy-4-nitro-5-sulfophenyl)-2H-tetrazolium-5-carboxanilide) assay and microscopic observation with concentrations ranging from 1 to 350 µM. Cytotoxicity was evaluated using J774.2 macrophage cell line and XTT assay. Lethal concentration 50 (LC50), selectivity index (SI) and structure-activity relationships were established. The activity compounds 4 (2-(ethylamino) hexadecan-1-ol), 6 (2-(butylamino) hexadecan-1-ol), 17 (tert-butyl N-(1-aminododecan-2-yl) carbamate) and 18 (tert-butyl N-(1-aminohexadecan-2-yl) carbamate) were further assessed against experimental S. venezuelensis infections in CD1 mice measuring reductions in the numbers of parthenogenetic females and egg passed in faeces. Mice were infected with 3,000 L3 and treated with 20 mg/kg/day for five days. RESULTS: In the screening study of 15 aminoalcohols [lauryl (n = 9); palmityl (n = 13); stearyl (n = 15) and alcohol derivatives], the presence of a palmitol chain was associated with the highest efficacy against L3 (LC50 31.9-39.1 µM). Alkylation of the 2-amino group with medium size fragments as ethyl or n-butyl showed the best larvicidal activity. The dialkylation did not improve efficacy. Aminoalcohols 4 and 6 showed the highest SI (1.5 and 1.6, respectively). With respect to diamine derivative compounds, a chain size of sixteen carbon atoms (palmitoyl chain, n = 13), and the alkylation of the 2-amino group with medium-sized fragments, were associated with the highest lethal activities. The presence of carbamoyl group in diamines 17 and 18 yielded high SI (1.7 and 1.4, respectively). Infected mice treated with aminoalcohol 6 showed reduction in parthenogenetic females (59 %) and eggs in faeces (51 %). CONCLUSIONS: These results support the potentiality of aminoalcohol and diamine sphingosine-related compounds as suitable prototypes for developing new promising drugs against strongyloidiasis.
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Amino Alcoholes/farmacología , Antihelmínticos/farmacología , Diaminas/farmacología , Strongyloides/efectos de los fármacos , Estrongiloidiasis/tratamiento farmacológico , Amino Alcoholes/química , Animales , Antihelmínticos/química , Diaminas/química , Masculino , Ratones , Estructura Molecular , Ratas , Estrongiloidiasis/parasitología , Relación Estructura-ActividadRESUMEN
BACKGROUND: Schistosomiasis is a water-borne disease afflicting over 261 million people in many areas of the developing countries with high morbidity and mortality. The control relies mainly on treatment with praziquantel. Fatty acid binding proteins (FABP) have demonstrated high levels of immune-protection against trematode infections. This study reports the immunoprotection induced by cross-reacting Fasciola hepatica FABP, native (nFh12) and recombinantly expressed using two different expression systems Escherichia coli (rFh15) and baculovirus (rFh15b) against Schistosoma mansoni infection. METHODS: BALB/c mice were vaccinated with native nFh12 or recombinant rFh15 and rFh15 FABP from F. hepatica formulated in adjuvant adaptation (ADAD) system with natural or chemical synthesised immunomodulators (PAL and AA0029) and then challenged with 150 cercariae of S. mansoni. Parasite burden, hepatic lesions and antibody response were studied in vaccination trials. Furthermore differences between rFh15 and rFh15b immunological responses (cytokine production, splenocyte population and antibody levels) were studied. RESULTS: Vaccination with nFh12 induced significant reductions in worm burden (83%), eggs in tissues (82-92%) and hepatic lesions (85%) compared to infected controls using PAL. Vaccination with rFh15 showed lower total worm burden (56-64%), eggs in the liver (21-61%), eggs in the gut (30-77%) and hepatic damage (67-69%) using PAL and AA0029 as immunomodulators. In contrast, mice vaccinated with rFh15b showed only reductions in eggs trapped in the liver and intestine (53 and 60%, respectively), and hepatic lesions (45%). We observed a significant rise in TNFα, IL-6, IL-2, IL-4 and high antibody response (IgG, IgG1, IgG2a, IgM and IgE) in mice immunised with either rFh15 or rFh15b. Moreover, mice immunised with rFh15b showed an increase in IFNγ and a decrease in B220 cells compared to untreated mice, and less production of IgG1 and IgM than in mice immunised by rFh15. CONCLUSIONS: Higher level of protection is obtained by using Fasciola hepatica-derived FABP protein against Schistosoma mansoni infection. Native FABP is more effective than both recombinant systems. It could be due to post-translational modifications or FABP isoform or changes in the recombinant proteins.
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Fasciola hepatica/inmunología , Proteínas de Unión a Ácidos Grasos/inmunología , Proteínas del Helminto/inmunología , Esquistosomiasis mansoni/prevención & control , Animales , Anticuerpos Antihelmínticos/inmunología , Protección Cruzada , Sistemas de Liberación de Medicamentos , Fasciola hepatica/genética , Proteínas de Unión a Ácidos Grasos/administración & dosificación , Proteínas de Unión a Ácidos Grasos/genética , Femenino , Proteínas del Helminto/genética , Humanos , Interleucina-2/genética , Interleucina-2/inmunología , Interleucina-4/inmunología , Ratones , Ratones Endogámicos BALB C , Proteínas Recombinantes/administración & dosificación , Proteínas Recombinantes/genética , Proteínas Recombinantes/inmunología , Esquistosomiasis mansoni/inmunología , Esquistosomiasis mansoni/parasitología , VacunaciónRESUMEN
Fasciolosis is listed as one of the most important neglected tropical diseases according with the World Health Organization and is also considered as a reemerging disease in the human beings. Despite there are several studies describing the immune response induced by Fasciola hepatica in the mammalian host, investigations aimed at identifying the expression profile of genes involved in inducing hepatic injury are currently scarce. Data presented here belong to a time-course investigation of the gene expression profile in the liver of BALB/c mice infected with F. hepatica metacercariae at 7 and 21 days after experimental infection. The data published here have been deposited in NCBI's Gene Expression Omnibus and are accessible through GEO Series accession number GSE69588, previously published by Rojas-Caraballo et al. (2015) in PLoS One [1].
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BACKGROUND: Fasciola hepatica infection still remains one of the helminthic neglected tropical diseases (NTDs). It has a huge worldwide distribution, affecting mainly cattle and, sometimes, human beings. In addition to data reported about the immunological response induced by helminthic infections and that induced by Fasciola hepatica, little is known about the gene expression profile in its organ target, the liver, which is where adult worms are established and live for long periods of time, causing its characteristic pathology. In the present work, we study both the early and late gene expression profiles in the livers of mice infected with F. hepatica metacercariae using a microarray-based methodology. METHODOLOGY: A total of 9 female-6-week-old BALB/c mice (Charles River Laboratories, Barcelona, Spain) weighing 20 to 35 g were used for the experiments. Two groups of BALB/c mice were orally infected with seven F. hepatica metacercariae, and the other group remained untreated and served as a control. Mice were humanely euthanized and necropsied for liver recovery, histological assessment of hepatic damage, RNA isolation, microarray design and gene expression analysis on the day of infection (t0), seven days post-infection (t7) and twenty-one days post-infection (t21). RESULTS: We found that F. hepatica infection induces the differential expression of 128 genes in the liver in the early stage of infection and 308 genes in the late stage, and most of them are up-regulated. The Ingenuity Pathway Analysis revealed significant changes in the pathways related to metabolism, biosynthesis and signaling as well as genes implicated in inducing liver-toxicity, injury and death. CONCLUSION: The present study provides us insights at the molecular level about the underlying mechanisms used by F. hepatica, leading to liver damage and its subsequent pathophysiology. The expression pattern obtained here could also be used to explain the lack of association between infection with F. hepatica and cholangiocarcinoma. However, more studies should be performed to confirm this hypothesis.
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Fasciola hepatica/crecimiento & desarrollo , Fascioliasis/genética , Redes Reguladoras de Genes , Hígado/metabolismo , Metacercarias/crecimiento & desarrollo , Animales , Modelos Animales de Enfermedad , Fasciola hepatica/patogenicidad , Fascioliasis/parasitología , Fascioliasis/patología , Femenino , Perfilación de la Expresión Génica , Regulación de la Expresión Génica , Interacciones Huésped-Parásitos , Hígado/parasitología , Hígado/patología , Metacercarias/patogenicidad , Ratones , Ratones Endogámicos BALB C , Anotación de Secuencia MolecularRESUMEN
BACKGROUND: Schistosomiasis is the third most devastating tropical disease worldwide caused by blood flukes of the genus Schistosoma. This parasitic disease is due to immunologic reactions to Schistosoma eggs trapped in tissues. Egg-released antigens stimulate tissue-destructive inflammatory and granulomatous reactions, involving different immune cell populations, including T cells and granulocytes. Granulomas lead to collagen fibers deposition and fibrosis, resulting in organ damage. Praziquantel (PZQ) is the drug of choice for treating all species of schistosomes. However, PZQ kills only adult Schistosoma worms, not immature stages. The inability of PZQ to abort early infection or prevent re-infection, and the lack of prophylactic effect prompt the need for novel drugs and strategies for the prevention of schistosomiasis. METHODOLOGY/PRINCIPAL FINDINGS: Using in vitro and in vivo approaches, we have found that the alkylphospholipid analog edelfosine kills schistosomula, and displays anti-inflammatory activity. The combined treatment of PZQ and edelfosine during a few days before and after cercariae infection in a schistosomiasis mouse model, simulating a prophylactic treatment, led to seven major effects: a) killing of Schistosoma parasites at early and late development stages; b) reduction of hepatomegaly; c) granuloma size reduction; d) down-regulation of Th1, Th2 and Th17 responses at late post-infection times, thus inhibiting granuloma formation; e) upregulation of IL-10 at early post-infection times, thus potentiating anti-inflammatory actions; f) down-regulation of IL-10 at late post-infection times, thus favoring resistance to re-infection; g) reduction in the number of blood granulocytes in late post-infection times as compared to infected untreated animals. CONCLUSIONS/SIGNIFICANCE: Taken together, these data suggest that the combined treatment of PZQ and edelfosine promotes a high decrease in granuloma formation, as well as in the cellular immune response that underlies granuloma development, with changes in the cytokine patterns, and may provide a promising and effective strategy for a prophylactic treatment of schistosomiasis.
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Granuloma/prevención & control , Inflamación/prevención & control , Éteres Fosfolípidos/uso terapéutico , Praziquantel/uso terapéutico , Esquistosomiasis/tratamiento farmacológico , Animales , Antihelmínticos/administración & dosificación , Antihelmínticos/uso terapéutico , Citocinas/genética , Citocinas/metabolismo , Regulación de la Expresión Génica , Ratones , Éteres Fosfolípidos/administración & dosificaciónRESUMEN
Fatty acid binding proteins (FABP) from Fasciola hepatica have demonstrated immune cross-protection against schistosomes. The present study was conducted to develop a new formulation of the recombinant FABP rFh15 with the synthetic immunomodulator AA0029 in the adjuvant adaptation (ADAD) vaccination system and to evaluate its ability to induce immune response and protection against the challenge with Schistosoma bovis cercariae. Immunization of BALB/c mice showed high levels of TNFα, IFNγ, interleukin (IL)-2, IL-6, and IL-4 in splenocyte supernatant culture and also high levels of serum specific anti-rFh15 IgG, IgG1, IgG2a IgE and IgM antibodies suggesting a mixed Th1/Th2 immune response. Using this approach, high levels of protection against experimental challenge with S. bovis cercariae were observed in the mouse and hamster models. A marked reduction up to 64% in worm burden, as well as in the number of eggs retained in liver (66%) and intestine (77%) and hepatic lesions (42%), was achieved in vaccinated BALB/c mice. Golden hamsters vaccinated and challenged in similar conditions had reductions in recovered worms (83%), liver eggs (90%), intestine eggs (96%), liver lesions (56%) and worm fecundity (48-80%). These data suggest that formulation of rFh15 in the ADAD vaccination system using the AA0029 immunomodulator could be a good option to drive an effective immunological response against schistosomiasis.
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Adyuvantes Inmunológicos/síntesis química , Diaminas/inmunología , Proteínas de Unión a Ácidos Grasos/inmunología , Esquistosomiasis/veterinaria , Vacunación/veterinaria , Animales , Anticuerpos Antihelmínticos/sangre , Cricetinae , Citocinas/análisis , Fasciola hepatica/química , Femenino , Citometría de Flujo , Inmunidad Celular , Inmunización Secundaria/veterinaria , Inmunoglobulinas/sangre , Masculino , Mesocricetus , Ratones , Ratones Endogámicos BALB C , Distribución Aleatoria , Proteínas Recombinantes/inmunología , Schistosoma/inmunología , Esquistosomiasis/prevención & control , Bazo/citología , Bazo/inmunología , Linfocitos T/citología , Vacunación/métodosRESUMEN
Several efforts have been made to identify anti-schistosomiasis vaccine candidates and new vaccination systems. The fatty acid binding protein (FAPB) has been shown to induce a high level of protection in trematode infection. The adjuvant adaptation (ADAD) vaccination system was used in this study, including recombinant FABP, a natural immunomodulator and saponins. Mice immunised with the ADAD system were able to up-regulate proinflammatory cytokines (IL-1 and IL-6) and induce high IgG2a levels. Moreover, there was a significant reduction in worm burden, egg liver and hepatic lesion in vaccinated mice in two independent experiments involving Schistosoma bovis infected mice. The foregoing data shows that ADAD system using FABP provide a good alternative for triggering an effective immune response against animal schistosomiasis.
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Fasciola hepatica/inmunología , Proteínas de Unión a Ácidos Grasos/inmunología , Proteínas del Helminto/inmunología , Esquistosomiasis/prevención & control , Vacunas Sintéticas , Adyuvantes Inmunológicos/química , Animales , Citocinas/metabolismo , Fasciola hepatica/química , Femenino , Proteínas del Helminto/química , Inyecciones Subcutáneas , Ratones , Ratones Endogámicos BALB C , Saponinas de Quillaja/inmunología , Distribución Aleatoria , Proteínas Recombinantes/química , Proteínas Recombinantes/inmunología , Schistosoma/inmunología , Esquistosomiasis/parasitología , Bazo/citología , Bazo/inmunología , Vacunación/métodos , Vacunas Sintéticas/administración & dosificación , Vacunas Sintéticas/química , Vacunas Sintéticas/inmunologíaRESUMEN
Fasciolosis is considered the most widespread trematode disease affecting grazing animals around the world; it is currently recognised by the World Health Organisation as an emergent human pathogen. Triclabendazole is still the most effective drug against this disease; however, resistant strains have appeared and developing an effective vaccine against this disease has increasingly become a priority. Several bioinformatics tools were here used for predicting B- and T-cell epitopes according to the available data for Fasciola hepatica protein amino acid sequences. BALB/c mice were immunised with the synthetic peptides by using the ADAD vaccination system and several immune response parameters were measured (antibody titres, cytokine levels, T-cell populations) to evaluate their ability to elicit an immune response. Based on the immunogenicity results so obtained, seven peptides were selected to assess their protection-inducing ability against experimental infection with F. hepatica metacercariae. Twenty-four B- or T-epitope-containing peptides were predicted and chemically synthesised. Immunisation of mice with peptides so-called B1, B2, B5, B6, T14, T15 and T16 induced high levels of total IgG, IgG1 and IgG2a (p<0.05) and a mixed Th1/Th2/Th17/Treg immune response, according to IFN-γ, IL-4, IL-17 and IL-10 levels, accompanied by increased CD62L+ T-cell populations. A high level of protection was obtained in mice vaccinated with peptides B2, B5, B6 and T15 formulated in the ADAD vaccination system with the AA0029 immunomodulator. The bioinformatics approach used in the present study led to the identification of seven peptides as vaccine candidates against the infection caused by Fasciola hepatica (a liver-fluke trematode). However, vaccine efficacy must be evaluated in other host species, including those having veterinary importance.
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Epítopos de Linfocito B/inmunología , Epítopos de Linfocito T/inmunología , Fasciola hepatica/química , Fasciola hepatica/inmunología , Fascioliasis/inmunología , Péptidos/inmunología , Secuencia de Aminoácidos , Animales , Anticuerpos Antihelmínticos/sangre , Anticuerpos Antihelmínticos/inmunología , Análisis por Conglomerados , Citocinas/sangre , Citocinas/genética , Modelos Animales de Enfermedad , Epítopos de Linfocito B/química , Epítopos de Linfocito T/química , Fascioliasis/genética , Fascioliasis/metabolismo , Fascioliasis/mortalidad , Fascioliasis/parasitología , Fascioliasis/prevención & control , Femenino , Perfilación de la Expresión Génica , Inmunoglobulina G/sangre , Inmunoglobulina G/inmunología , Ratones , Péptidos/síntesis química , Vacunas Antiprotozoos/inmunologíaRESUMEN
Fascioliasis is a parasitic disease that mainly affects cattle and sheep, causing significant economic losses with a great impact in developing countries. Human fascioliasis is becoming more important with the high endemicity in some countries of the world. Previous studies have shown the importance of Fasciola hepatica fatty acid binding proteins (FABP) as protective molecules against fascioliasis in various animal models including mice, rabbits, and sheep. Our studies have shown the protective efficacy of recombinant FABP (rFh15) when the protein is formulated in the adjuvant adaptation system (ADAD), using either natural or synthetic immunomodulators. The ADAD system is most effective when it is used 5 days before each dose of specific vaccine antigen. The results showed survival rates of up to 50% with less severe hepatic lesions and high levels of IgG2a or IFNγ in immunized mice, using the ADAD system, compared to survival rates of 13% with no hepatic lesion reduction and high levels of IgG1 and IL-4 in those mice immunized with the simplified mode (ADADs).
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Inmunidad Adaptativa/inmunología , Fasciola hepatica/inmunología , Fascioliasis/prevención & control , Proteínas de Unión a Ácidos Grasos/inmunología , Vacunas/inmunología , Análisis de Varianza , Animales , Anticuerpos Antihelmínticos/biosíntesis , Anticuerpos Antihelmínticos/sangre , Citocinas/biosíntesis , Citocinas/sangre , Ensayo de Inmunoadsorción Enzimática , Fascioliasis/inmunología , Femenino , Inmunidad Celular , Inmunoglobulina G/biosíntesis , Inmunoglobulina G/sangre , Ratones , Ratones Endogámicos BALB C , Conejos , Bazo/citología , Bazo/inmunologíaRESUMEN
Although largely considered benign, Plasmodium vivax causes disease in nearly 75 million people each year and the available strategies are not sufficient to reduce the burden of disease, therefore pointing to vaccine development as a cost-effective control measure. In this study, the P. vivax merozoite surface protein 10 (MSP-10) was expressed as a recombinant protein in Escherichia coli and purified by affinity chromatography. High antigenicity was observed since sera from P. vivax-infected patients strongly recognized rPvMSP10. The immunogenicity of rPvMSP10 was tested in Aotus monkeys, comparing responses induced by formulations with Freund's adjuvant, Montanide ISA720 or aluminum hydroxide. All formulations produced high antibody titers recognizing the native protein in late schizonts. Despite inducing strong antibody production, none of the formulations protected immunized Aotus monkeys upon experimental challenge.
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Antígenos de Protozoos/inmunología , Vacunas contra la Malaria/inmunología , Malaria Vivax/prevención & control , Plasmodium vivax/inmunología , Proteínas Protozoarias/inmunología , Adyuvantes Inmunológicos , Hidróxido de Aluminio/inmunología , Animales , Anticuerpos Antiprotozoarios/sangre , Aotus trivirgatus , Adyuvante de Freund/inmunología , Humanos , Inmunidad Humoral , Malaria Vivax/inmunología , Manitol/análogos & derivados , Manitol/inmunología , Ácidos Oléicos/inmunología , Proteínas Recombinantes/inmunologíaRESUMEN
Rhoptry proteins have been extensively shown to be important in invasion and parasitophorous vacuole (PV) formation. This work evaluates the immunogenicity and protective efficacy of Plasmodium vivax RAP2 in the non-human Aotus primate model, when expressed as a recombinant molecule in E. coli and formulated in Freund and Alum hydroxide adjuvants. Our results show that rPvRAP2 is immunogenic in both formulations, finding a trend of higher cytokine levels in immunized monkeys, specially in IL-4 levels (using Freund's adjuvant) and IL-5 (using Alum hydroxide). RAP2 is suggested as a P. vivax-vaccine candidate since immunized monkeys exhibited lower parasitemias than control groups after being experimentally challenged with the P. vivax VCG-I strain.
Asunto(s)
Aotidae/inmunología , Fenómenos Inmunogenéticos/inmunología , Vacunas contra la Malaria/inmunología , Plasmodium vivax/genética , Plasmodium vivax/inmunología , Proteínas Protozoarias/genética , Proteínas Protozoarias/inmunología , Animales , Modelos Animales de Enfermedad , Fenómenos Inmunogenéticos/genética , Vacunas contra la Malaria/genética , Vacunas contra la Malaria/metabolismo , Plasmodium vivax/metabolismo , Proteínas Protozoarias/aislamiento & purificación , Proteínas Protozoarias/metabolismoRESUMEN
Four Plasmodium species cause malaria in humans, Plasmodium falciparum being the most widely studied to date. All Plasmodium species have paired club-shaped organelles towards their apical extreme named rhoptries that contain many lipids and proteins which are released during target cell invasion. P. falciparum RhopH3 is a rhoptry protein triggering important immune responses in patients from endemic regions. It has also been shown that anti-RhopH3 antibodies inhibit in vitro invasion of erythrocytes. Recent immunisation studies in mice with the Plasmodium yoelii and Plasmodium berghei RhopH3 P. falciparum homologue proteins found that they are able to induce protection in murine models. This study described identifying and characterising RhopH3 protein in Plasmodium vivax; it is encoded by a seven exon gene and expressed during the parasite's asexual stage. PvRhopH3 has similar processing to its homologue in P. falciparum and presents a cellular immunolocalisation pattern characteristic of rhoptry proteins.
Asunto(s)
Antígenos de Protozoos/química , Antígenos de Protozoos/fisiología , Plasmodium falciparum/metabolismo , Plasmodium vivax/metabolismo , Proteínas Protozoarias/química , Proteínas Protozoarias/fisiología , Secuencia de Aminoácidos , Animales , Antígenos de Protozoos/genética , Clonación Molecular , Exones , Ratones , Microscopía Confocal , Modelos Genéticos , Datos de Secuencia Molecular , Proteínas Protozoarias/genética , Conejos , Análisis de Secuencia de ADN , Especificidad de la EspecieRESUMEN
Plasmodium vivax merozoites have been found to specifically invade immature red blood cells (reticulocytes) and this preference has been associated with two proteins named reticulocyte binding protein-1 and protein-2 (PvRBP1 and PvRBP2). Previous reticulocyte binding assays using 15-mer synthetic peptides spanning the entire PvRBP1 sequence have shown that 25 out of the 195 peptides synthesised (grouped into 4 different regions) displayed high affinity binding to reticulocytes. The PvRBP1 region III (amino acids 1998-2348), encompassing 9 of the previously described high-affinity reticulocyte binding peptides, was expressed as a recombinant protein in the present study. This protein has been shown to be antigenic in humans and it has also been able to induce good humoral and cellular immune responses in Aotus nancymaae monkeys. Despite its high immunogenicity, no protective efficacy was observed in the immunised animals.
Asunto(s)
Antígenos de Protozoos/inmunología , Vacunas contra la Malaria/inmunología , Malaria Vivax/prevención & control , Proteínas de la Membrana/inmunología , Plasmodium vivax/inmunología , Proteínas Protozoarias/inmunología , Proteínas Recombinantes/inmunología , Animales , Anticuerpos Antiprotozoarios/sangre , Aotidae , Humanos , Inmunización , Activación de Linfocitos , Vacunas contra la Malaria/administración & dosificación , Malaria Vivax/inmunología , Proteínas de la Membrana/administración & dosificación , Proteínas de la Membrana/genética , Proteínas de la Membrana/metabolismo , Plasmodium vivax/patogenicidad , Proteínas Protozoarias/administración & dosificación , Proteínas Protozoarias/genética , Proteínas Protozoarias/metabolismo , Proteínas Recombinantes/administración & dosificación , Proteínas Recombinantes/metabolismoRESUMEN
Plasmodium vivax is currently the most widespread of the four parasite species causing malaria in humans around the world. It causes more than 75 million clinical episodes per year, mainly on the Asian and American continents. Identifying new antigens to be further tested as anti-P. vivax vaccine candidates has been greatly hampered by the difficulty of maintaining this parasite cultured in vitro. Taking into account that one of the most promising vaccine candidates against Plasmodium falciparum is the rhoptry-associated protein 2, we have identified the P. falciparum rhoptry-associated protein 2 homologue in P. vivax in the present study. This protein has 400 residues, having an N-terminal 21 amino-acid stretch compatible with a signal peptide and, as occurs with its falciparum homologue, it lacks repeat sequences. The protein is expressed in asexual stage P. vivax parasites and polyclonal sera raised against this protein recognised a 46 kDa band in parasite lysate in a Western blot assay.