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1.
Exp Parasitol ; : 108801, 2024 Jul 13.
Artículo en Inglés | MEDLINE | ID: mdl-39009180

RESUMEN

The agropastoral farmers have employed Turraea vogelii (TVL), Senna podocarpa (SPL), and Jaundea pinnata (JPL) leaves for treating various diseases, including intestinal parasites in livestock and the human population in Nigeria. Gastrointestinal nematodes are highly significant to livestock production and people's health, and natural products are interesting as sources of new drugs. In this study, we evaluated the effectiveness of extracts derived from these plants in treating parasitic infections using third-stage infective larvae (L3) of Strongyloides venezuelensis. We obtained crude extracts using n-gexane (Hex), ethyl acetate (Ea), and methanol (Met). The extracts were analyzed for their phytochemical composition, and their ability to prevent hemolysis were tested. The mean concentrations of total phenols in SPL Hex, SPL Ea, and SPL Met were 92.3±0.3, 103.0±0.4, and 128.2±0.5 mg/100 g, respectively. Total tannin concentrations for JPL Ea, SPL Ea, SPL Hex, and TVL Hex were 60.3±0.1, 89.2±0.2, 80.0±0.1, and 66.6±0.3 mg/100 g, respectively. The mean lethal concentration (LC50) at 72 h for JPL Ea 39 (26-61) µg/mL. SPL Ea was 39 (34-45) µg/mL, and TVL Hex 31 (26-36) µg/mL. The antiparasitic activities of the extracts against L3 were dose- and time-dependent. All the extracts were slightly hemolytic to the erythrocytes. In this study, the plant extract tested demonstrated significant anti-S. venezuelensis activity. These phytobotanical extracts could be used to create formulations for the potential treatment of helminthiasis in animals and humans.

2.
Int J Mol Sci ; 24(19)2023 Sep 30.
Artículo en Inglés | MEDLINE | ID: mdl-37834216

RESUMEN

Only a small number of infected people are highly susceptible to schistosomiasis, showing high levels of infection or severe liver fibrosis. The susceptibility to schistosome infection is influenced by genetic background. To assess the genetic basis of susceptibility and identify the chromosomal regions involved, a backcross strategy was employed to generate high variation in schistosomiasis susceptibility. This strategy involved crossing the resistant C57BL/6J mouse strain with the susceptible CBA/2J strain. The resulting F1 females (C57BL/6J × CBA/2J) were then backcrossed with CBA/2J males to generate the backcross (BX) cohort. The BX mice exhibited a range of phenotypes, with disease severity varying from mild to severe disease, lacking a fully resistant group. We observed four levels of infection intensity using cluster and principal component analyses and K-means based on parasitological, pathological, and immunological trait measurements. The mice were genotyped with 961 informative SNPs, leading to the identification of 19 new quantitative trait loci (QTL) associated with parasite burden, liver lesions, white blood cell populations, and antibody responses. Two QTLs located on chromosomes 15 and 18 were linked to the number of granulomas, liver lesions, and IgM levels. The corresponding syntenic human regions are located in chromosomes 8 and 18. None of the significant QTLs had been reported previously.


Asunto(s)
Neoplasias Hepáticas , Esquistosomiasis mansoni , Esquistosomiasis , Humanos , Masculino , Femenino , Ratones , Animales , Esquistosomiasis mansoni/genética , Ratones Endogámicos C57BL , Modelos Genéticos , Schistosoma mansoni/genética , Ratones Endogámicos CBA , Susceptibilidad a Enfermedades , Genómica
3.
Exp Parasitol ; 220: 108043, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-33197440

RESUMEN

Strongyloidiasis is a parasitosis that represents a public health problem, in tropical regions. The present study aimed to investigate the anthelmintic effects of several extracts of Argemone mexicana, as well as its main component berberine (Ber) against the third-stage larvae (L3) of Strongyloides venezuelensis in-vitro experiments. Also, the anti-hemolytic activity of the extract, fractions, and Ber were tested in human erythrocytes. A dose-response anthelminthic bioassay demonstrated Ber as the most effective component, followed by methanolic subfraction (Fr3) and finally the crude extract of A. mexicana (Am) showing LC50 response values of 1.6, 19.5, and 92.1 µg/mL, at 96 h respectively. Also, Am, Fr3, and Ber did not produce significant hemolysis against human erythrocytes (p ≤ 0.05). Am and Fr3 showed erythrocyte protection effect capacity at the membrane level (p ≤ 0.05). Furthermore, Ber was found to have an antioxidant activity of 168.18 µg/mL. According to the results, the Fr3 of A. mexicana, and particularly Ber, exhibited potent in-vitro effects against L3 of S. venezuelensis, without hemolytic activity against human erythrocytes and presented good antioxidant capacity. In conclusion, the extracts of A. mexicana and the main component have activity against S. venezuelensis, nevertheless, further studies are required to elucidate the mechanism of action.


Asunto(s)
Antihelmínticos/farmacología , Argemone/química , Berberina/farmacología , Extractos Vegetales/farmacología , Strongyloides/efectos de los fármacos , Análisis de Varianza , Animales , Antihelmínticos/química , Antihelmínticos/uso terapéutico , Berberina/química , Berberina/uso terapéutico , Bioensayo , Relación Dosis-Respuesta a Droga , Eritrocitos/efectos de los fármacos , Heces/parasitología , Hemólisis/efectos de los fármacos , Humanos , Larva/efectos de los fármacos , Dosificación Letal Mediana , Masculino , Extractos Vegetales/química , Extractos Vegetales/uso terapéutico , Hojas de la Planta/química , Tallos de la Planta/química , Ratas , Ratas Wistar , Estrongiloidiasis/tratamiento farmacológico
4.
Trop Med Int Health ; 23(9): 992-1001, 2018 09.
Artículo en Inglés | MEDLINE | ID: mdl-29920859

RESUMEN

OBJECTIVE: To evaluate the performance of Rapid-Heat LAMPellet assay in field conditions for diagnosis of urogenital schistosomiasis in an endemic area in Cubal, Angola, and to assess the reproducibility in a reference laboratory. METHODS: A total of 172 urine samples from school-age children were tested for microhaematuria, microscopic detection of Schistosoma haematobium eggs and LAMP for DNA detection. Urine samples were stored in a basic equipped laboratory. Field-LAMP tests were performed with and without prior DNA extraction from urine samples, and the results were read by turbidity and by colour change. When field procedures were finished, samples were sent to a reference laboratory to be reanalysed by LAMP. RESULTS: A total of 83 of 172 (48.3%) were positive for microhaematuria, 87/172 (50.6%) were microscopy-positive for S. haematobium eggs detection, and 127/172 (73.8%) showed LAMP-positive results for detecting S. haematobium using purified DNA and 109/172 (63.4%) without prior DNA extraction. MacNemar's test showed a statistical significant relation between LAMP results and microscopy-detected S. haematobium infections and microhaematuria (P < 0.001 in both cases), respectively. When samples of purified DNA were reanalysed in a reference laboratory in Spain using the same LAMP methodology, the overall reproducibility achieved 72.1%. CONCLUSIONS: The ease of use, simplicity and feasibility demonstrated by LAMP assay in field conditions together with the acceptable level of reproducibility achieved in a reference laboratory support the use of LAMP assay as an effective test for molecular diagnosis of urogenital schistosomiasis in endemic remote areas.


Asunto(s)
Laboratorios , Técnicas de Amplificación de Ácido Nucleico/métodos , Schistosoma haematobium/aislamiento & purificación , Esquistosomiasis Urinaria/diagnóstico , Esquistosomiasis Urinaria/orina , Adolescente , Angola , Animales , Niño , Preescolar , Femenino , Humanos , Masculino , Reproducibilidad de los Resultados , Sensibilidad y Especificidad
5.
BMC Infect Dis ; 17(1): 94, 2017 01 23.
Artículo en Inglés | MEDLINE | ID: mdl-28114888

RESUMEN

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.


Asunto(s)
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 , Vacunación
6.
Pharm Biol ; 54(8): 1398-407, 2016 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-26789098

RESUMEN

Context C-6-Geranylated flavonoids possess promising biological activities. These substances could be a source of lead compounds for the development of therapeutics. Objective The study was designed to evaluate their antibacterial and antileishmanial activity. Materials and methods C-6-Geranylated flavanones were tested in micromolar concentrations against promastigote forms of Leishmania brazilensis, L. donovani, L. infantum, and L. panamensis against methicillin-resistant Staphylococcus aureus (MRSA); and synergistic potential with antibiotics was analyzed. IC50 values (after 72 h) were calculated and compared with that of miltefosine. Flow cytometry and DNA fragmentation analysis were used the mechanism of the effect. Geranylated flavanones or epigallocatechin gallate were combined with oxacillin, tetracycline, and ciprofloxacin, and the effects of these two-component combinations were evaluated. Minimal inhibitory concentrations (MICs) and minimal bactericidal concentrations (MBCs) were established (after 24 h), the synergy was measured by the checkerboard titration technique, and the sums of the fractional inhibitory concentrations (∑FICs) were computed. Results 3'-O-Methyl-5'-O-methyldiplacone and 3'-O-methyldiplacone showed good antileishmanial activities (IC50 8-42 µM). 3'-O-Methyl-5'-hydroxydiplacone activates the apoptotic death at leishmanias, the effect of 3'-O-methyl-5'-O-methyldiplacone has another mechanism. The test of the antibacterial activity showed good effects of 3'-O-methyldiplacol and mimulone against MRSA (MIC 2-16 µg/mL), and in six cases, the results showed synergistic effects when combined with oxacillin. Synergistic effects were also found for the combination of epigallocatechin gallate with tetracycline or oxacillin. Conclusion This work demonstrates anti-MRSA and antileishmanial potential of geranylated flavanones and uncovers their promising synergistic activities with antibiotics. In addition, the mechanism of antileishmanial effect is proposed.


Asunto(s)
Antibacterianos/farmacología , Antiparasitarios/farmacología , Flavonoides/farmacología , Leishmania/efectos de los fármacos , Magnoliopsida , Staphylococcus aureus Resistente a Meticilina/efectos de los fármacos , Extractos Vegetales/farmacología , Antibacterianos/aislamiento & purificación , Antiparasitarios/aislamiento & purificación , Apoptosis/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Sinergismo Farmacológico , Flavonoides/aislamiento & purificación , Frutas , Leishmania/crecimiento & desarrollo , Magnoliopsida/química , Staphylococcus aureus Resistente a Meticilina/crecimiento & desarrollo , Pruebas de Sensibilidad Microbiana , Fitoterapia , Extractos Vegetales/aislamiento & purificación , Plantas Medicinales , Prenilación , Factores de Tiempo
7.
Exp Parasitol ; 154: 134-42, 2015 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-25936981

RESUMEN

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.


Asunto(s)
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/métodos
8.
Molecules ; 20(6): 11554-68, 2015 Jun 23.
Artículo en Inglés | MEDLINE | ID: mdl-26111182

RESUMEN

Thirteen aminoalcohols and eight diamines were obtained and tested against Trypanosoma cruzi epimastigotes strains MG, JEM and CL-B5 clone. Some of them were equal or more potent (1.0-6.6 times) than the reference compound nifurtimox. From them, three aminoalcohols and two diamines were selected for amastigotes assays. Compound 5 was as potent as the reference drug nifurtimox against amastigotes of the CL-B5 strain (IC50 = 0.6 µM), with a selectivity index of 54.


Asunto(s)
Enfermedad de Chagas/tratamiento farmacológico , Diaminas/administración & dosificación , Tripanocidas/administración & dosificación , Trypanosoma cruzi/efectos de los fármacos , Alcoholes/administración & dosificación , Alcoholes/química , Animales , Enfermedad de Chagas/parasitología , Chlorocebus aethiops , Diaminas/química , Humanos , Tripanocidas/química , Trypanosoma cruzi/patogenicidad , Células Vero
9.
Exp Parasitol ; 145: 145-51, 2014 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-25124941

RESUMEN

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.


Asunto(s)
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/inmunología
10.
Expert Opin Pharmacother ; 25(4): 409-420, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38511392

RESUMEN

INTRODUCTION: Schistosomiasis, one of the current Neglected Tropical Diseases (NTDs) affects over 230 million people globally, with nearly 700 million at risk in more than 74 countries. Praziquantel (PZQ) has served as the primary treatment for the past four decades; however, its effectiveness is limited as it solely eliminates adult worms. In regions where infections are frequent, PZQ exhibits only temporary efficacy and has restricted potential to disrupt the prolonged transmission of the disease. AREAS COVERED: A comprehensive exploration using the PubMed database was conducted to review current pharmacotherapy approaches for schistosomiasis. This review also encompasses recent research findings related to potential novel therapeutics and the repurposing of existing drugs. EXPERT OPINION: Current schistosoma treatment strategies, primarily relying on PZQ, face challenges like temporary effectiveness and limited impact on disease transmission. Drug repurposing, due to economic constraints, is decisive for NTDs. Despite PZQ's efficacy, its failure to prevent reinfection highlights the need for complementary strategies, especially in regions with persistent environmental foci. Integrating therapies against diverse schistosome stages boosts efficacy and impedes resistance. Uncovering novel agents is essential to address resistance concerns in tackling this neglected tropical disease. Integrated strategies present a comprehensive approach to navigate the complex challenges.


Asunto(s)
Reposicionamiento de Medicamentos , Enfermedades Desatendidas , Praziquantel , Esquistosomiasis , Esquistosomicidas , Humanos , Esquistosomiasis/tratamiento farmacológico , Animales , Praziquantel/uso terapéutico , Enfermedades Desatendidas/tratamiento farmacológico , Enfermedades Desatendidas/prevención & control , Esquistosomicidas/uso terapéutico , Resistencia a Medicamentos , Schistosoma/efectos de los fármacos
11.
Vaccine ; 42(15): 3445-3454, 2024 May 31.
Artículo en Inglés | MEDLINE | ID: mdl-38631956

RESUMEN

Major histocompatibility complex class II (MHC-II) molecules are involved in immune responses against pathogens and vaccine candidates' immunogenicity. Immunopeptidomics for identifying cancer and infection-related antigens and epitopes have benefited from advances in immunopurification methods and mass spectrometry analysis. The mouse anti-MHC-II-DR monoclonal antibody L243 (mAb-L243) has been effective in recognising MHC-II-DR in both human and non-human primates. It has also been shown to cross-react with other animal species, although it has not been tested in livestock. This study used mAb-L243 to identify Staphylococcus aureus and Salmonella enterica serovar Typhimurium peptides binding to cattle and swine macrophage MHC-II-DR molecules using flow cytometry, mass spectrometry and two immunopurification techniques. Antibody cross-reactivity led to identifying expressed MHC-II-DR molecules, together with 10 Staphylococcus aureus peptides in cattle and 13 S. enterica serovar Typhimurium peptides in swine. Such data demonstrates that MHC-II-DR expression and immunocapture approaches using L243 mAb represents a viable strategy for flow cytometry and immunopeptidomics analysis of bovine and swine antigen-presenting cells.


Asunto(s)
Anticuerpos Monoclonales , Macrófagos , Salmonella typhimurium , Staphylococcus aureus , Animales , Bovinos , Porcinos/inmunología , Staphylococcus aureus/inmunología , Anticuerpos Monoclonales/inmunología , Macrófagos/inmunología , Salmonella typhimurium/inmunología , Antígenos de Histocompatibilidad Clase II/inmunología , Reacciones Cruzadas/inmunología , Citometría de Flujo , Espectrometría de Masas , Ratones
12.
J Med Entomol ; 60(5): 1081-1087, 2023 09 12.
Artículo en Inglés | MEDLINE | ID: mdl-37410021

RESUMEN

Tick-borne diseases have increased significantly in Europe and Spain in recent years. One strategy explored for tick surveillance and control is the study of the microbiota. The focus is on understanding the relationships between pathogens and endosymbionts within the microbiota and how these relationships can alter these arthropods' vectorial capacity. Thus, it is pivotal to depict the bacterial communities composing the microbiota of ticks present in specific territories. This work aimed to describe the microbiota present in 29 adult individuals of 5 tick species collected from 4 provinces of Castilla y Leon in northwestern Spain from 2015 to 2022. DNA extraction and sequencing of the V4 hypervariable region of 16S-rRNA was performed on the tick samples, with subsequent analysis of diversity, taxonomic composition, and correlations between genera of microorganisms. There were no differences in the alpha diversity of microbiota by tick species, nor were compositional changes evident at the phylum level for microorganisms. However, interindividual differences at the microbial genus level allowed spatial differentiation of the 5 tick species included in the study. Correlation analyses showed complex interactions between different genera of microbiota members. These findings provide an initial insight into the composition of the gut microbiota of various tick species in northwestern Spain, which can contribute to establishing surveillance and control measures to reduce diseases such as rickettsiosis, Lyme disease, and Crimean-Congo hemorrhagic fever.


Asunto(s)
Microbioma Gastrointestinal , Ixodidae , Enfermedades por Picaduras de Garrapatas , Garrapatas , Humanos , Animales , Garrapatas/microbiología , Ixodidae/microbiología , España , Enfermedades por Picaduras de Garrapatas/epidemiología , ARN Ribosómico 16S/genética
13.
Am J Trop Med Hyg ; 109(6): 1368-1371, 2023 12 06.
Artículo en Inglés | MEDLINE | ID: mdl-37931298

RESUMEN

Onchocerciasis has been declared eliminated in Ecuador and surveillance measures are of great interest. In this study, we examined the infectivity rates of Simulium exiguum by Onchocerca volvulus in previously hyperendemic areas in Esmeraldas province of Ecuador. These areas had previously undergone mass administration of ivermectin, which led to the interruption of transmission in 2009 and the certification of elimination in 2014. The study included three communities in Río Cayapas and one in Río Canandé, and a total of 2,950 adult S. exiguum were collected in 2018. We used quantitative polymerase chain reaction with O. volvulus O-150 plasmid control DNA to analyze 59 pools. Our findings revealed that the infectivity rates were zero, indicating that the transmission of O. volvulus remained suspended in the area.


Asunto(s)
Vólvulo Intestinal , Onchocerca volvulus , Oncocercosis , Simuliidae , Humanos , Animales , Adulto , Oncocercosis/diagnóstico , Oncocercosis/epidemiología , Oncocercosis/prevención & control , Onchocerca volvulus/genética , Reacción en Cadena en Tiempo Real de la Polimerasa , Ecuador/epidemiología , Ivermectina/uso terapéutico , Onchocerca/genética
14.
Vaccines (Basel) ; 10(8)2022 Aug 10.
Artículo en Inglés | MEDLINE | ID: mdl-36016178

RESUMEN

Strongyloidiasis, caused by Strongyloides stercoralis, is a neglected parasitic disease that represents a serious public health problem. In immunocompromised patients, this parasitosis can result in hyperinfection or disseminated disease with high levels of mortality. In previous studies, the mRNAs encoding for the 14-3-3 and major antigen proteins were found to be expressed at high levels in S. stercoralis L3 larvae, suggesting potential key roles in parasite-host interactions. We have produced them as recombinant proteins (rSs14-3-3 and rSsMA) in a bacterial protein expression system. The serum levels of anti-rSs14-3-3 and anti-rSsMA IgGs are increased upon infection with S. venezuelensis, validating the use of the mouse model since the native 14-3-3 and MA proteins induce an immune response. Each recombinant protein was formulated in the adjuvant adaptation (ADAD) vaccination system and injected twice, subcutaneously, in CD1 mice that were experimentally infected with 3000 S. venezuelensis L3 to evaluate their protective and immunomodulatory activity. Our results, including the number of parthenogenetic females, number of eggs in stool samples and the analysis of the splenic and intestinal indexes, show that the vaccines did not protect against infection. The immunization with rSs14-3-3 induced changes in the cytokine profile in mice, producing higher expression of IL-10, TGF-ß, IL-13 and TNF-α in the spleen, suggesting a Th2/Treg-type response with an increase in TNF-α levels, confirming its role as an immunomodulator.

15.
Vaccines (Basel) ; 9(9)2021 Sep 04.
Artículo en Inglés | MEDLINE | ID: mdl-34579225

RESUMEN

Nowadays, safe and efficacious vaccines represent powerful and cost-effective tools for global health and economic growth. In the veterinary field, these are undoubtedly key tools for improving productivity and fighting zoonoses. However, cases of persistent infections, rapidly evolving pathogens having high variability or emerging/re-emerging pathogens for which no effective vaccines have been developed point out the continuing need for new vaccine alternatives to control outbreaks. Most licensed vaccines have been successfully used for many years now; however, they have intrinsic limitations, such as variable efficacy, adverse effects, and some shortcomings. More effective adjuvants and novel delivery systems may foster real vaccine effectiveness and timely implementation. Emerging vaccine technologies involving nanoparticles such as self-assembling proteins, virus-like particles, liposomes, virosomes, and polymeric nanoparticles offer novel, safe, and high-potential approaches to address many vaccine development-related challenges. Nanotechnology is accelerating the evolution of vaccines because nanomaterials having encapsulation ability and very advantageous properties due to their size and surface area serve as effective vehicles for antigen delivery and immunostimulatory agents. This review discusses the requirements for an effective, broad-coverage-elicited immune response, the main nanoplatforms for producing it, and the latest nanovaccine applications for fighting animal pathogens.

16.
Iran J Parasitol ; 16(1): 91-100, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33786051

RESUMEN

BACKGROUND: Schistosomiasis has been identified as a major public health problem in tropical countries. The present study aimed to investigate the schistosomicidal effects of the methanolic extract of Argemone mexicana L. and its active component, berberine against Schistosoma mansoni on in-vitro experiments. METHODS: S. mansoni adults were used. Various concentrations of the methanolic extract (10 - 200 µg/ml) and berberine (2.5 - 50 µM) were tested from 24 to 72 h. The viability of S. mansoni was confirmed with an invertoscope-microscope. Furthermore, cytotoxic (Hemolysis test), and antioxidant (DPPH radical scavenging assay) capacities were determined. RESULTS: The viability tests on S. mansoni showed that A. mexicana at 50 µg/mL is lethal at 48 h and berberine at 10 µM is lethal at 24 h. The hemolytic activity at 1,000 µg/mL was 2.9% for A. mexicana and 90.2% for berberine. The antioxidant capacities shown by A. mexicana and berberine, were EC50 156.3 and 84.1 µg/mL, respectively. CONCLUSION: The extract of A. mexicana and berberine demonstrated high antischistosomal activities in low concentration and short exposure time on the in-vitro model.

17.
Sci Rep ; 11(1): 4476, 2021 02 24.
Artículo en Inglés | MEDLINE | ID: mdl-33627744

RESUMEN

Schistosoma mansoni is less susceptible to the antiparasitic drug ivermectin than other helminths. By inhibiting the P-glycoprotein or cytochrome P450 3A in mice host or parasites in a murine model, we aimed at increasing the sensitivity of S. mansoni to the drug and thus preventing infection. We assigned 124 BALB/c mice to no treatment, treatment with ivermectin only or a combination of ivermectin with either cobicistat or elacridar once daily for three days before infecting them with 150 S. mansoni cercariae each. The assignment was done by batches without an explicit randomization code. Toxicity was monitored. At eight weeks post-infection, mice were euthanized. We determined number of eggs in intestine and liver, adult worms in portal and mesenteric veins. Disease was assessed by counting granulomas/cm2 of liver and studying organ weight indices and total weight. IgG levels in serum were also considered. No difference between groups treated with ivermectin only or in combination with cobicistat or elacridar compared with untreated, infected controls. Most mice treated with ivermectin and elacridar suffered severe neurological toxicity. In conclusion, systemic treatment with ivermectin, even in the presence of pharmacological inhibition of P-glycoprotein or cytochrome P450 3A, did not result in effective prophylaxis for S. mansoni infection in an experimental murine model.


Asunto(s)
Acridinas/farmacología , Cobicistat/farmacología , Ivermectina/farmacología , Schistosoma mansoni/efectos de los fármacos , Esquistosomiasis mansoni/tratamiento farmacológico , Tetrahidroisoquinolinas/farmacología , Miembro 1 de la Subfamilia B de Casetes de Unión a ATP/metabolismo , Animales , Antiparasitarios/farmacología , Citocromo P-450 CYP3A/metabolismo , Femenino , Granuloma/tratamiento farmacológico , Granuloma/parasitología , Inmunoglobulina G/metabolismo , Intestinos/parasitología , Hígado/parasitología , Masculino , Venas Mesentéricas/metabolismo , Venas Mesentéricas/parasitología , Ratones , Ratones Endogámicos BALB C , Recuento de Huevos de Parásitos/métodos , Esquistosomiasis mansoni/metabolismo
18.
J Clin Med ; 10(3)2021 Jan 24.
Artículo en Inglés | MEDLINE | ID: mdl-33498845

RESUMEN

Schistosomiasis is a parasitic disease that affects 143 million people in endemic countries. This work analyzed overexpressed sequences from the cercaria phase to the early schistosomulum phase using bioinformatics tools to predict host interaction and selected proteins for predicting T cell epitopes. The final peptides were chemically synthesized, and their toxicity was evaluated in vitro. Peptides were formulated in the Adjuvant Adaptation (ADAD) vaccination system and injected into BALB/c mice that were challenged with S. mansoni cercariae to assess protection and immunogenicity. A total of 39 highly expressed S.mansoni proteins were identified as being of potential interest. Three T cell peptides predicted to bind MHC mouse and human class II were synthesized and formulated for vaccination. SmGSP and SmIKE reduced the number of eggs trapped in the liver by more than 50% in challenged BALB/c mice. The liver of mice vaccinated with either SmGSP or SmTNP had a significantly reduced affected liver surface. Transcriptome-based T cell peptides elicit partial protection and could be candidates for a multiantigen vaccine.

19.
Dis Markers ; 2020: 8042705, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32774514

RESUMEN

Schistosomiasis is considered a neglected parasitic disease. Around 280,000 people die from it annually, and more than 779 million people are at risk of getting infected. The schistosome species which infect human beings are Schistosoma mansoni, Schistosoma haematobium, Schistosoma intercalatum, Schistosoma japonicum, Schistosoma guineensis, and Schistosoma mekongi. This disease is also of veterinary significance; the most important species being Schistosoma bovis since it causes the disease in around 160 million livestock in Africa and Asia. This work was aimed at designing and developing a genus-specific loop-mediated isothermal amplification (LAMP) method for detecting the most important schistosome species affecting humans and for the species-specific detection of S. bovis. Bioinformatics tools were used for primer design, and the LAMP method was standardised for detecting the ITS-1 region from S. intercalatum, S. haematobium, S. mansoni, S. japonicum, and S. bovis DNA (generic test) and the NADH 1 gene for specifically detecting S. bovis (at different DNA concentrations). Detection limits achieved were 1 pg DNA for S. mansoni, 0.1 pg for S. haematobium, 1 pg for S. intercalatum, and 10 pg for S. bovis. No amplification for S. japonicum DNA was obtained. The LAMP designed for the amplification of S. bovis NADH-1 worked specifically for this species, and no other DNA from other schistosome species included in the study was amplified. Two highly sensitive LAMP methods for detecting different Schistosoma species important for human and veterinary health were standardised. These methods could be very useful for the diagnosis and surveillance of schistosome infections.


Asunto(s)
Técnicas de Diagnóstico Molecular/métodos , Técnicas de Amplificación de Ácido Nucleico/métodos , Schistosoma/genética , Esquistosomiasis/diagnóstico , Animales , Biología Computacional/métodos , ADN Protozoario/genética , Diagnóstico Precoz , Humanos , Límite de Detección , Técnicas de Diagnóstico Molecular/normas , Técnicas de Amplificación de Ácido Nucleico/normas , Schistosoma/clasificación , Schistosoma/aislamiento & purificación , Especificidad de la Especie
20.
Parasit Vectors ; 13(1): 552, 2020 Nov 07.
Artículo en Inglés | MEDLINE | ID: mdl-33160406

RESUMEN

BACKGROUND: Trichuris trichiura (human whipworm) infects an estimated 477 million individuals worldwide. In addition to T. trichiura, other Trichuris species can cause an uncommon zoonosis and a number of human cases have been reported. The diagnosis of trichuriasis has relied traditionally on microscopy. Recently, there is an effort to use molecular diagnostic methods, mainly qPCR. LAMP technology could be an alternative for qPCR especially in low-income endemic areas. Trichuris muris, the causative agent of trichuriasis in mice, is of great importance as a model for human trichuriasis. Here, we evaluate the diagnostic utility of a new LAMP assay in an active experimental mouse trichuriasis in parallel with parasitological method by using stool and, for the first time, urine samples. METHODS: Stool and urine samples were collected from mice infected with eggs of T. muris. The dynamics of infection was determined by counting the number of eggs per gram of faeces. A LAMP based on the 18S rRNA gene from T. muris was designed. Sensitivity and specificity of LAMP was tested and compared with PCR. Stool and urine samples were analysed by both LAMP and PCR techniques. RESULTS: Trichuris muris eggs were detected for the first time in faeces 35 days post-infection. LAMP resulted specific and no cross-reactions were found when using 18 DNA samples from different parasites. The detection limit of the LAMP assay was 2 pg of T. muris DNA. When testing stool samples by LAMP we obtained positive results on day 35 p.i. and urine samples showed amplification results on day 20 p.i., i.e. 15 days before the onset of T. muris eggs in faeces. CONCLUSIONS: To the best of our knowledge, we report, for the first time, a novel LAMP assay (Whip-LAMP) for sensitive detection of T. muris DNA in both stool and urine samples in a well-established mice experimental infection model. Considering the advantages of urine in molecular diagnosis in comparison to stool samples, should make us consider the possibility of starting the use urine specimens in molecular diagnosis and for field-based studies of human trichuriasis where possible. Further studies with clinical samples are still needed.


Asunto(s)
ADN de Helmintos/aislamiento & purificación , Heces/parasitología , Técnicas de Diagnóstico Molecular/métodos , Técnicas de Amplificación de Ácido Nucleico/métodos , Tricuriasis/diagnóstico , Trichuris/genética , Animales , Modelos Animales de Enfermedad , Femenino , Ratones , Recuento de Huevos de Parásitos , Organismos Libres de Patógenos Específicos , Tricuriasis/orina
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