Evaluation of the Immune Response of a Candidate Phage-Based Vaccine against Rhipicephalus microplus (Cattle Tick)

Cattle tick (Rhipicephalus microplus) represents a severe problem causing substantial economic losses, estimated in billions of dollars annually. Currently, chemical acaricides represent the most widely used control method. However, several problems such as resistance have been described. Phage-based vaccines represent a fast and low-cost tool for antigen delivery. In this regard, the objective of the present work was to develop a candidate phage-based vaccine displaying a cattle tick antigen (Bm86-derived Sbm7462 antigen) on the surface of bacteriophage M13. Phage ELISA and dot blotting analysis confirmed the display of the antigen. Vaccine immunogenicity was evaluated using a bovine monocyte-derived dendritic cell-based ex vivo assay and a murine in vivo assay. The ex vivo model showed the maturation of dendritic cells after being pulsed with the phage-based vaccine. The humoral response was confirmed in the in vivo assay. These results demonstrated the capacity of the phage-based vaccine to induce both humoral and cellular immune-specific responses. Importantly, this is the first report describing a control method for cattle ticks using a candidate phage-based vaccine. Further studies to evaluate the immunogenicity in a bovine model are needed. The current approach represents a promising alternative to control cattle tick infestations.

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Analysis of Bm86 conserved epitopes: is a global vaccine against Cattle Tick Rhipicephalus microplus possible?

Revista Brasileira de Parasitologia Veterinária ◽

10.1590/s1984-296120180056 ◽

2018 ◽

Author(s):

Isabella Maiumi Zaidan Blecha ◽

Bárbara Guimarães Csordas ◽

André de Abreu Rangel Aguirre ◽

Rodrigo Casquero Cunha ◽

Marcos Valério Garcia ◽

...

Keyword(s):

Control Method ◽

Phylogenetic Analyses ◽

Rhipicephalus Microplus ◽

Economic Losses ◽

Antigenic Determinants ◽

Cattle Tick ◽

Universal Vaccine ◽

Cattle Ticks ◽

Geographical Regions ◽

Different Populations

Abstract The cattle tick Rhipicephalus microplus causes significant economic losses in agribusiness. Control of this tick is achieved mainly through the application of chemical acaricides, often resulting in contamination of animal food products and of the environment. Another major concern associated with acaricide use is the increasing reports of resistance of this tick vector against the active ingredients of many commercial products. An alternative control method is vaccination. However, the commercially available vaccine based on a protein homologous to Bm86 exhibits variations in efficacy relative to the different geographical locations. This study aimed to identify antigenic determinants of the sequences of proteins homologous to Bm86. Phylogenetic analyses were performed to determine the extent of divergence between different populations of R. microplus to identify the sequence that could be used as a universal vaccine against the multiple geographically distinct populations of R. microplus and related tick species. Considering the extensive sequence and functional polymorphism observed among strains of R. microplus from different geographical regions, we can conclude that it may be possible to achieve effective vaccination against these cattle ticks using a single universal Bm86-based antigen.

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Histological, Biomechanical, and Biological Properties of Genipin-Crosslinked Decellularized Peripheral Nerves

International Journal of Molecular Sciences ◽

10.3390/ijms22020674 ◽

2021 ◽

Vol 22 (2) ◽

pp. 674

Author(s):

Óscar Darío García-García ◽

Marwa El Soury ◽

David González-Quevedo ◽

David Sánchez-Porras ◽

Jesús Chato-Astrain ◽

...

Keyword(s):

Ex Vivo ◽

Nerve Repair ◽

Wistar Rat ◽

Biomechanical Properties ◽

Biological Properties ◽

Suitable Alternative ◽

Promising Alternative ◽

Histological Pattern ◽

The Impact

Acellular nerve allografts (ANGs) represent a promising alternative in nerve repair. Our aim is to improve the structural and biomechanical properties of biocompatible Sondell (SD) and Roosens (RS) based ANGs using genipin (GP) as a crosslinker agent ex vivo. The impact of two concentrations of GP (0.10% and 0.25%) on Wistar rat sciatic nerve-derived ANGs was assessed at the histological, biomechanical, and biocompatibility levels. Histology confirmed the differences between SD and RS procedures, but not remarkable changes were induced by GP, which helped to preserve the nerve histological pattern. Tensile test revealed that GP enhanced the biomechanical properties of SD and RS ANGs, being the crosslinked RS ANGs more comparable to the native nerves used as control. The evaluation of the ANGs biocompatibility conducted with adipose-derived mesenchymal stem cells cultured within the ANGs confirmed a high degree of biocompatibility in all ANGs, especially in RS and RS-GP 0.10% ANGs. Finally, this study demonstrates that the use of GP could be an efficient alternative to improve the biomechanical properties of ANGs with a slight impact on the biocompatibility and histological pattern. For these reasons, we hypothesize that our novel crosslinked ANGs could be a suitable alternative for future in vivo preclinical studies.

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In vitro activity of the hydroalcoholic extract of Chenopodium ambrosioides against engorged females of Rhipicephalus (Boophilus) microplus

Arquivos do Instituto Biológico ◽

10.1590/1808-1657000222016 ◽

2018 ◽

Vol 84 (0) ◽

Author(s):

Eduardo Oliveira ◽

Manoela da Silva ◽

Lew Sprenger ◽

Daniela Pedrassani

Keyword(s):

High Efficiency ◽

Boophilus Microplus ◽

Vitro Activity ◽

Economic Losses ◽

Cattle Tick ◽

Distilled Water ◽

In Vitro Activity ◽

Chenopodium Ambrosioides ◽

Cattle Ticks

ABSTRACT: Rhipicephalus (Boophilus) microplus, known as the cattle tick, is a cause of great economic losses for dairy cattle farming because of its high frequency of occurrence and the difficulty in controlling it. The aim of this study was to evaluate the in vitro activity of Chenopodium ambrosioides extract on R. (B.) microplus. For this purpose, 125 females were selected and classified into five groups according to their weight, in order to ensure that the females used presented homogeneous weight. The treatments comprised 40 and 60% extracts of Chenopodium ambrosioides, distilled water, ethanol (70ºGL) and 12.5% amitraz. The extracts of C. ambrosioides (40 and 60%) showed effectiveness of 99.7 and 100% and higher percentages of dead females than the other treatments: 64 and 96%, respectively (p<0.001). In the groups exposed to distilled water and ethanol (70º GL), 92 and 88% of the females maintained oviposition. In the females exposed to 40 and 60% extracts, oviposition of 36 and 4% occurred, respectively. It was concluded that the extract of Chenopodium ambrosioides, at both concentration evaluated, had high efficiency against engorged females of cattle ticks.

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Acaricidal activity of leaves of Morus nigra against the cattle tick Rhipicephalus microplus

Arquivo Brasileiro de Medicina Veterinária e Zootecnia ◽

10.1590/1678-4162-8994 ◽

2017 ◽

Vol 69 (3) ◽

pp. 523-528 ◽

Cited By ~ 1

Author(s):

A.C.S. Dantas ◽

D.P. Freire ◽

G.R. Souza ◽

J.R.G.S. Almeida ◽

L.A. Rolim ◽

...

Keyword(s):

Phenolic Compounds ◽

Ethanolic Extract ◽

Adult Tick ◽

Immersion Test ◽

Rhipicephalus Microplus ◽

Acaricidal Activity ◽

Cattle Tick ◽

Chloroform Fraction ◽

Morus Nigra ◽

Cattle Ticks

ABSTRACT The acaricidal activity of crude ethanolic extract and fractions from the leaves of Morus nigra (Moraceae) was carried out on female cattle ticks Rhipicephalus microplus, using the adult immersion test. The mortality and fertility of females exposed to different concentrations of hexane, chloroform and ethyl acetate fractions, as well as ethanolic extract of M. nigra with concentrations of 5, 10 and 25mg/ml were evaluated using three treatment groups, two control groups and triplicate tests. The study also identified the main phenolic compounds of the extract and fractions of this species by HPLC. The chloroform fraction of leaves of M. nigra (25mg/mL) showed the best results for this species, obtaining 62.6% of inhibition of oviposition, 39.3% of eggs eclosion average and 65.4% of effectiveness. HPLC analysis revealed the presence of phenolic compounds, which may be related to biological activity shown by the extracts, which can be used as an alternative control against R. microplus adult tick.

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Rhipicephalus (Boophilus) microplus: expression and characterization of Bm86-CG in Pichia pastoris

Revista Brasileira de Parasitologia Veterinária ◽

10.1590/s1984-29612011000200003 ◽

2011 ◽

Vol 20 (2) ◽

pp. 103-110 ◽

Cited By ~ 4

Author(s):

Rodrigo Casquero Cunha ◽

Renato Andreotti ◽

Fábio Pereira Leivas Leite

Keyword(s):

Pichia Pastoris ◽

Boophilus Microplus ◽

Economic Losses ◽

Cattle Tick ◽

High Antibody ◽

Western Blot Assay ◽

Development Of Resistance ◽

Cattle Ticks ◽

Antibody Titers

The cattle tick Rhipicephalus (Boophilus) microplus is responsible for great economic losses. It is mainly controlled chemically, with limitations regarding development of resistance to the chemicals. Vaccines may help control this parasite, thereby reducing tick pesticide use. In this light, we performed subcloning of the gene of the protein Bm86-GC, the homologue protein that currently forms the basis of vaccines (GavacTM and TickGardPLUS) that have been developed against cattle ticks. The subcloning was done in the pPIC9 expression vector, for transformation in the yeast Pichia pastoris. This protein was characterized by expression of the recombinant Mut+ strain, which expressed greater quantities of protein. The expressed protein (rBm86-CG) was recognized in the Western-blot assay using anti-Gavac, anti-TickGard, anti-larval extract and anti-rBm86-CG polyclonal sera. The serum produced in cattle vaccinated with the antigen CG rBm86 presented high antibody titers and recognized the native protein. The rBm86-GC has potential relevance as an immunogen for vaccine formulation against cattle ticks.

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Detection of Root Canal Isthmuses in Molars by Map-Reading Dynamic using CBCT images

Brazilian Dental Journal ◽

10.1590/0103-6440201302380 ◽

2013 ◽

Vol 24 (6) ◽

pp. 569-574 ◽

Cited By ~ 15

Author(s):

Jesus Djalma Pecora ◽

Carlos Estrela ◽

Mike Reis Bueno ◽

Olavo Cesar Porto ◽

Ana Helena Goncalves Alencar ◽

...

Keyword(s):

Ex Vivo ◽

Chi Square ◽

Map Reading ◽

Mandibular Molars ◽

In Vivo Assay ◽

Apical Direction ◽

Chi Square Test ◽

Level Of Significance ◽

Ex Vivo Assay

The aim of this study was to detect root isthmuses in maxillary and mandibular molars and evaluate their frequencies using map-reading dynamics in CBCT images. Two hundred extracted human maxillary and mandibular molars were used in ex vivo assay. A consecutive sample of two hundred maxillary and mandibular molars (first and second) was selected from CBCT exams. The isthmuses were detected from the pulp orifice to the apex and were recorded according to their beginning and their end, into categories: 1. begin and end in cervical third; 2. beginning in cervical third and end in middle third; 3. beginning in cervical third and end in apical third; 4. beginning and end in middle third; 5. begin in middle third and end in apical third; 6. beginning and end in apical third; 7. no isthmus. The scans were obtained in different planes with map-reading in axial slices of 0.5 mm/0.5 mm involved the coronal to apical direction. The frequencies of isthmus were analyzed according to the level of root and evaluated by Chi-square test. The level of significance was set at α=0.05. The presence of isthmus detected in maxillary molars was 86% in ex vivo assay and 62% in vivo assay, whereas in mandibular molars was observed 70% in ex vivo assay and 72% in vivo assay. The frequency of isthmus was high in both study models. The map-reading dynamics in CBCT images was found to be precise to detect the localization of isthmus.

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Chemical composition and acaricidal activity of seed oils of the palms Mauritia flexuosa and Mauritiella armata in Rhipicephalus microplus (Ixodidae)

Research Society and Development ◽

10.33448/rsd-v10i13.21078 ◽

2021 ◽

Vol 10 (13) ◽

pp. e167101321078

Author(s):

Geisa Simone Caldeira Santos ◽

Franciellen Morais-Costa ◽

João Carlos Gomes Figueiredo ◽

Juliana Pimenta Cruz ◽

Sônia Ribeiro Arrudas ◽

...

Keyword(s):

Palmitoleic Acid ◽

Impact Ionization ◽

Integrated Control ◽

Larval Mortality ◽

Rhipicephalus Microplus ◽

Economic Losses ◽

Chemical Compositions ◽

Promising Alternative ◽

Palm Trees ◽

Mauritia Flexuosa

Rhipicephalus microplus is responsible for considerable economic losses in tropical and subtropical regions. Plant compounds have been utilized as alternative to conventional acaricids. The objective in this study was to evaluate the effects of fixed oils extracted from seeds of Mauritia flexuosa and Mauritiella armata, palm trees typical of the Brazilian Cerrado on tick R. microplus.The fixed oils were used against engorged females and larvae by biocarrapaticidograms and larval mortality by larval pack tests (LPT). Chemical compositions of the oils were evaluated by gas chromatography using an electron impact ionization detector and showed the presence of the compounds: palmitoleic acid, linoleic acid, palmitic acid, and myristic acid. In the biocarrapaticidogram, the oil from M. flexuosa and M. armata at 5% and 10% concentrations showed efficacies > 80%. Regarding the effect of fixed oils from palm trees on R. microplus larvae, mortality above 80% was observed at all concentrations tested.These bioproducts are a promising alternative for controlling this tick and may be adapted into current integrated control methods for cattle farming.

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Calculation of the efficacy of vaccines against tick infestations on cattle

Revista Brasileira de Parasitologia Veterinária ◽

10.1590/s1984-29612013000400019 ◽

2013 ◽

Vol 22 (4) ◽

pp. 571-578 ◽

Cited By ~ 4

Author(s):

Rodrigo Casquero Cunha ◽

Renato Andreotti ◽

Marcos Valério Garcia ◽

André de Abreu Rangel Aguirre ◽

Alexandre Leitão

Keyword(s):

Control Method ◽

The Other ◽

Economic Losses ◽

Tick Population ◽

Scientific Publications ◽

Cattle Ticks ◽

Resistant Strains ◽

Main Factors ◽

Method Of Assessment ◽

Vaccine Effect

Cattle ticks are responsible for great economic losses in cattle farming worldwide, and their main control method, chemicals, has been showing problems, whether resulting from the development of resistant strains of ticks or environmental contamination. Research studies directed toward developing vaccines against ticks are emerging. One way to evaluate those vaccines is to calculate the percentage of efficacy. The aim of this study was to analyze scientific publications archived in PubMed that used this method of assessment and discuss the main factors that may affect its calculation. Thus, 25 articles addressing this subject were selected. The percentage of efficacy was usually calculated in one of two ways, with one considering the reduced fertility of eggs and the other not. The latter method may underestimate the vaccine efficacy, and the most complete formula for calculating the efficacy reflects how much the vaccine actually affects the infestation. In our view, the use of the complete formula for calculating the percentage of efficacy is broader and more representative of the vaccine effect on the tick population.

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LIPID NANOPARTICLES FOR TRANSDERMAL DELIVERY OF CELECOXIB: AN IN VITRO AND IN VIVO INVESTIGATION

INDIAN DRUGS ◽

10.53879/id.56.08.11694 ◽

2019 ◽

Vol 56 (08) ◽

pp. 38-48

Author(s):

S. V Shinde ◽

S Nikam ◽

P Raut ◽

M. K. Ghag ◽

Keyword(s):

Solid Lipid Nanoparticles ◽

Ex Vivo ◽

Research Work ◽

Lipid Nanoparticles ◽

Inflammatory Activity ◽

Promising Alternative ◽

Solid Lipid ◽

Anti Inflammatory

In the present research work, celecoxib (CXB) loaded solid lipid nanoparticles (SLNs) were prepared using the probe sonication method, wherein Glyceryl monostearate and Tween 80 were used as solid lipid and surfactant, respectively. To obtain the statistically optimized batch, 32 factorial design was applied. The optimized batch was characterized physicochemically and evaluated through DSC, SEM and XRD studies. The mean particle size of the optimized batch was found to be 135.41± 0.24 nm with a mean % entrapment efficiency of 80 ± 1.69%. The optimized batch was further lyophilized and dispersed into 1% w/v Carbopol 934P to form a gel. Prepared gel was further evaluated for in vitro drug release, occlusivity, ex vivo permeability, local toxicity, in vivo anti-inflammatory activity and accelerated stability study. The study resulted in stable, safe and prolonged anti-inflammatory activity with quick onset of action. Hence, celecoxib loaded solid lipid nanoparticles can be considered as promising alternative to conventional topical systems.

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Validation of an In vitro-in vivo Assay System for Evaluation of Transdermal Delivery of Caffeine

Drug Delivery Letters ◽

10.2174/2210303108666180903102107 ◽

2019 ◽

Vol 9 (1) ◽

pp. 15-20 ◽

Cited By ~ 2

Author(s):

Fanni Farner ◽

Luca Bors ◽

Ágnes Bajza ◽

Gellért Karvaly ◽

István Antal ◽

...

Keyword(s):

Ex Vivo ◽

Assay System ◽

Diffusion Cell ◽

Rat Skin ◽

Topical Formulation ◽

Franz Diffusion Cell ◽

Topical Drugs ◽

In Vivo Assay

Introduction: Degree of skin penetration of topical drugs and cosmetics is a crucial point concerning their effects and tolerability. For testing drug delivery across the dermal barrier different in vitro and in vivo assays have been developed. Caffeine has been shown to have beneficial effects against skin aging, sunburn and hair-loss, and it is protective against melanoma and non-melanoma type skin cancers. Aim of our study was to set up an assay system to evaluate caffeine penetration from topical formulation into the skin. Methods: Franz diffusion cells consisting of either a filter paper or an artificial membrane or rat skin were used as in vitro/ex vivo test systems and transdermal microdialysis in anaesthetized rats was performed as an in vivo assay. Results: Results indicate that Franz diffusion cell studies provide a good approximation of the release of caffeine from the formulation but are not able to differentiate between 2% and 4% cream concentrations. The maximum concentrations (Cmax) in case of the 2% cream formulation were 708.3 (2.7 μm pore), 78.7 (0.8 µm pore), 45.3 (0.45 µm pore) and 44.9 (rat skin) µg/7.5 mL, respectively. The in vivo microdialysis experiments were in accordance with the in vitro and ex vivo results and gave more information on the dynamics and follicular and transcellular phases of drug penetration through the layers of the skin. Discussion and Conclusion: Taken together, Franz diffusion cell and transdermal microdialysis are a good combination to evaluate caffeine release and penetration into the skin from the formulations tested. This system might also be used for rapid testing of other hydrophilic topical drugs and has a benefit in the prediction for human skin absorption and tolerability studies, in an early phase of drug development.

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