scholarly journals Purification, Stability, and Immunogenicity Analyses of Five Bluetongue Virus Proteins for Use in Development of a Subunit Vaccine That Allows Differentiation of Infected from Vaccinated Animals

2014 ◽  
Vol 21 (3) ◽  
pp. 443-452 ◽  
Author(s):  
Jenna Anderson ◽  
Emmanuel Bréard ◽  
Karin Lövgren Bengtsson ◽  
Kjell-Olov Grönvik ◽  
Stéphan Zientara ◽  
...  
Keyword(s):  
Bluetongue Virus ◽  
Subunit Vaccine ◽  
Clinical Signs ◽  
Igg Antibody ◽  
Content Type ◽  
Vector Borne Diseases ◽  
Antibody Titers ◽  
A Subunit ◽  
Bluetongue Disease ◽  
Vector Borne

ABSTRACTBluetongue virus (BTV) causes bluetongue disease, a vector-borne disease of ruminants. The recent northerly spread of BTV serotype 8 in Europe resulted in outbreaks characterized by clinical signs in cattle, including unusual teratogenic effects. Vaccination has been shown to be crucial for controlling the spread of vector-borne diseases such as BTV. With the aim of developing a novel subunit vaccine targeting BTV-8 that allows differentiation of infected from vaccinated animals, five His-tagged recombinant proteins, VP2 and VP5 of BTV-8 and NS1, NS2, and NS3 of BTV-2, were expressed in baculovirus orEscherichia coliexpression systems for further study. Optimized purification protocols were determined for VP2, NS1, NS2, and NS3, which remained stable for detection for at least 560 to 610 days of storage at +4°C or −80°C, and Western blotting using sera from vaccinated or experimentally infected cattle indicated that VP2 and NS2 were recognized by BTV-specific antibodies. To characterize murine immune responses to the four proteins, mice were subcutaneously immunized twice at a 4-week interval with one of three protein combinations plus immunostimulating complex ISCOM-Matrix adjuvant or with ISCOM-Matrix alone (n= 6 per group). Significantly higher serum IgG antibody titers specific for VP2 and NS2 were detected in immunized mice than were detected in controls. VP2, NS1, and NS2 but not NS3 induced specific lymphocyte proliferative responses upon restimulation of spleen cells from immunized mice. The data suggest that these recombinant purified proteins, VP2, NS1, and NS2, could be an important part of a novel vaccine design against BTV-8.

scholarly journals Mapping the basic reproduction number (R0) for vector-borne diseases: A case study on bluetongue virus

Epidemics ◽  
2009 ◽  
Vol 1 (3) ◽  
pp. 153-161 ◽  
Author(s):  
N.A. Hartemink ◽  
B.V. Purse ◽  
R. Meiswinkel ◽  
H.E. Brown ◽  
A. de Koeijer ◽  
...  
Keyword(s):  
Basic Reproduction Number ◽  
Bluetongue Virus ◽  
Reproduction Number ◽  
Vector Borne Diseases ◽  
Vector Borne ◽  
The Basic Reproduction Number

scholarly journals Protection against Lethal Leptospirosis after Vaccination with LipL32 Coupled or Coadministered with the B Subunit of Escherichia coli Heat-Labile Enterotoxin

2012 ◽  
Vol 19 (5) ◽  
pp. 740-745 ◽  
Author(s):  
André A. Grassmann ◽  
Samuel R. Félix ◽  
Carolina Ximendes dos Santos ◽  
Marta G. Amaral ◽  
Amilton C. P. Seixas Neto ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Immune Response ◽  
Subunit Vaccine ◽  
Lethal Dose ◽  
Control Group ◽  
Hamster Model ◽  
Content Type ◽  
B Subunit ◽  
Heat Labile ◽  
A Subunit

ABSTRACTLeptospirosis, a worldwide zoonosis, lacks an effective, safe, and cross-protective vaccine. LipL32, the most abundant, immunogenic, and conserved surface lipoprotein present in all pathogenic species ofLeptospira, is a promising antigen candidate for a recombinant vaccine. However, several studies have reported a lack of protection when this protein is used as a subunit vaccine. In an attempt to enhance the immune response, we used LipL32 coupled to or coadministered with the B subunit of theEscherichia coliheat-labile enterotoxin (LTB) in a hamster model of leptospirosis. After homologous challenge with 5× the 50% lethal dose (LD50) ofLeptospira interrogans, animals vaccinated with LipL32 coadministered with LTB and LTB::LipL32 had significantly higher survival rates (P< 0.05) than animals from the control group. This is the first report of a protective immune response afforded by a subunit vaccine using LipL32 and represents an important contribution toward the development of improved leptospirosis vaccines.

scholarly journals Vertical Transmission of a Drosophila Endosymbiont Via Cooption of the Yolk Transport and Internalization Machinery

mBio ◽  
2013 ◽  
Vol 4 (2) ◽  
Author(s):  
Jeremy K. Herren ◽  
Juan C. Paredes ◽  
Fanny Schüpfer ◽  
Bruno Lemaitre
Keyword(s):  
Vertical Transmission ◽  
Fat Body ◽  
Germ Line ◽  
Ovarian Follicle ◽  
Follicle Cells ◽  
Content Type ◽  
Vector Borne Diseases ◽  
Severe Reduction ◽  
Female Germ Line ◽  
Vector Borne

ABSTRACTSpiroplasmais a diverse bacterial clade that includes many vertically transmitted insect endosymbionts, includingSpiroplasma poulsonii, a natural endosymbiont ofDrosophila melanogaster. These bacteria persist in the hemolymph of their adult host and exhibit efficient vertical transmission from mother to offspring. In this study, we analyzed the mechanism that underlies their vertical transmission, and here we provide strong evidence that these bacteria use the yolk uptake machinery to colonize the germ line. We show thatSpiroplasmareaches the oocyte by passing through the intercellular space surrounding the ovarian follicle cells and is then endocytosed into oocytes within yolk granules during the vitellogenic stages of oogenesis. Mutations that disrupt yolk uptake by oocytes inhibit verticalSpiroplasmatransmission and lead to an accumulation of these bacteria outside the oocyte. Impairment of yolk secretion by the fat body results inSpiroplasmanot reaching the oocyte and a severe reduction of vertical transmission. We propose a model in whichSpiroplasmafirst interacts with yolk in the hemolymph to gain access to the oocyte and then uses the yolk receptor, Yolkless, to be endocytosed into the oocyte. Cooption of the yolk uptake machinery is a powerful strategy for endosymbionts to target the germ line and achieve vertical transmission. This mechanism may apply to other endosymbionts and provides a possible explanation for endosymbiont host specificity.IMPORTANCEMost insect species, including important disease vectors and crop pests, harbor vertically transmitted endosymbiotic bacteria. Studies have shown that many facultative endosymbionts, includingSpiroplasma, confer protection against different classes of parasites on their hosts and therefore are attractive tools for the control of vector-borne diseases. The ability to be efficiently transmitted from females to their offspring is the key feature shaping associations between insects and their inherited endosymbionts, but to date, little is known about the mechanisms involved. In oviparous animals, yolk accumulates in developing eggs and serves to meet the nutritional demands of embryonic development. Here we show thatSpiroplasma coopts the yolk transport and uptake machinery to colonize the germ line and ensure efficient vertical transmission. The uptake of yolk is a female germ line-specific feature and therefore an attractive target for cooption by endosymbionts that need to maintain high-fidelity maternal transmission.

scholarly journals Endoparasites and vector-borne pathogens in dogs from Greek islands: pathogen distribution and zoonotic implications

2018 ◽  
Author(s):  
Anastasia Diakou ◽  
Angela Di Cesare ◽  
Simone Morelli ◽  
Mariasole Colombo ◽  
Lenaig Halos ◽  
...  
Keyword(s):  
Linear Models ◽  
Clinical Signs ◽  
Rhipicephalus Sanguineus ◽  
Toxocara Canis ◽  
Control Measures ◽  
Rickettsia Conorii ◽  
Vector Borne Diseases ◽  
Vector Borne ◽  
Endemic Areas ◽  
Of Greece

AbstractThe present study investigated the presence of endo- and ecto-parasites, and vector-borne pathogens, in dogs from four islands of Greece. A total of 200 owned and sheltered dogs were examined with different microscopic, serological and molecular methods.Of the examined dogs, 130 (65%) were positive for one or more parasites and/or vector-borne pathogens. The most common zoonotic intestinal helminths recorded were Ancylostomatidae (12.5%) and Toxocara canis (3.5%). Ninety-three dogs (46.5%) seroreacted to Rickettsia conorii. Twenty-two (11%) of them were also PCR positive and 7 (3.5%) showed corpuscoles suggestive of Rickettsia spp. on the blood smears. Nineteen dogs (9.5%) were seropositive for Ehrlichia canis, three of them being also PCR positive. Dogs positive for Anaplasma phagocytophilum-Anaplasma platys (1%), Dirofilaria immitis (0.5%) and Babesia canis (0.5%) were also found. Fleas and ticks were recorded in 53 (26.5%) and 50 (25%) dogs and all specimens were identified as Ctenocephalides felis felis and Rhipicephalus sanguineus sensu latu. Binary multiple univariate Generalized Linear Models were used to investigate factors and clinical signs related to the recorded positivity, while the association of specific signs with the pathogens was evaluated using tests of independence. Knowledge of occurrence and impact of zoonotic parasites and vector-borne pathogens in dog populations is crucial to prevent the infection in animals and people, and to control the risk of spreading of these pathogens in endemic and non-endemic areas.Author summaryBoth owned and sheltered dogs can harbor a variety of intestinal and extra-intestinal endoparasites, as well as vector-borne pathogens and ectoparasites, of zoonotic concern. Dog shelters and stray dogs are present in several touristic areas of Greece, including Sporades and Cyclades islands, where tourists often bring their pets with them, likely travelling from non-endemic to endemic areas. The present study has been carried out with the aim to evaluate the occurrence of the aforementioned pathogens. Data obtained showed that they are present in canine populations of Greece, with possibilities of infection for travelling dogs, which can also contribute to the spreading of zoonotic vector-borne diseases, introducing new pathogens in previously non-endemic areas. For these reasons, a constant monitoring of the epidemiological situation, improving control measures and correct diagnostic approaches are of primary importance for the prevention of canine and human infections, decreasing the spreading of potentially deadly pathogens.

Evaluation of the immunoprotective effects of IF-2 GTPase and SSU05-1022 as Streptococcus suis candidate subunit vaccine

2021 ◽  
Author(s):  
Tumei Chen ◽  
Chenchen Wang ◽  
Linlin Hu ◽  
Hao Lu ◽  
Fangyu Song ◽  
...  
Keyword(s):  
Recombinant Proteins ◽  
Subunit Vaccine ◽  
Streptococcus Suis ◽  
Cross Protection ◽  
Cytokine Levels ◽  
Antibody Titers ◽  
A Subunit ◽  
Suis Serotype ◽  
Lethal Doses ◽  
Mixed Protein

Aim: This study aims to develop a subunit vaccine with high cross-protection for Streptococcus suis. Materials & methods: Four-week-old female BALB/c mice were first immunized with a single and mixed protein. Various indicators, such as antibody titers and various cytokine levels, were further analyzed. Results: The results showed that purified recombinant proteins IF-2 and 1022 had a good protective effect against lethal doses of S. suis serotype 2 and S. suis serotype 9. This study showed immunization with recombinant proteins. Conclusion: IF-2 and 1022 can enhance cross-protection against S. suis serotypes 2 and 9.

scholarly journals Disrupting the Transmission of a Vector-Borne Plant Pathogen

2011 ◽  
Vol 78 (3) ◽  
pp. 638-643 ◽  
Author(s):  
Nabil Killiny ◽  
Arash Rashed ◽  
Rodrigo P. P. Almeida
Keyword(s):  
Cell Attachment ◽  
Transmission Rate ◽  
Disease Spread ◽  
Content Type ◽  
Vector Borne Diseases ◽  
Whole Cells ◽  
Complex Biological Process ◽  
Bacterial Transmission ◽  
Vector Borne ◽  
Cuticular Surface

ABSTRACTApproaches to control vector-borne diseases rarely focus on the interface between vector and microbial pathogen, but strategies aimed at disrupting the interactions required for transmission may lead to reductions in disease spread. We tested if the vector transmission of the plant-pathogenic bacteriumXylella fastidiosawas affected by three groups of molecules: lectins, carbohydrates, and antibodies. Although not comprehensively characterized, it is known thatX. fastidiosaadhesins bind to carbohydrates, and that these interactions are important for initial cell attachment to vectors, which is required for bacterial transmission from host to host. Lectins with affinity to substrates expected to occur on the cuticular surface of vectors colonized byX. fastidiosa, such as wheat germ agglutinin, resulted in statistically significant reductions in transmission rate, as did carbohydrates withN-acetylglucosamine residues. Presumably, lectins bound to receptors on the vector required for cell adhesion/colonization, while carbohydrate-saturated adhesins onX. fastidiosa's cell surface. Furthermore, antibodies againstX. fastidiosawhole cells, gum, and afimbrial adhesins also resulted in transmission blockage. However, no treatment resulted in the complete abolishment of transmission, suggesting that this is a complex biological process. This work illustrates the potential to block the transmission of vector-borne pathogens without directly affecting either organism.

scholarly journals Coagulases as Determinants of Protective Immune Responses against Staphylococcus aureus

2012 ◽  
Vol 80 (10) ◽  
pp. 3389-3398 ◽  
Author(s):  
Molly McAdow ◽  
Andrea C. DeDent ◽  
Carla Emolo ◽  
Alice G. Cheng ◽  
Barry N. Kreiswirth ◽  
...  
Keyword(s):  
Staphylococcus Aureus ◽  
Immune Responses ◽  
Von Willebrand Factor ◽  
Subunit Vaccine ◽  
Gene Sequences ◽  
Content Type ◽  
A Subunit ◽  
Von Willebrand ◽  
Willebrand Factor

ABSTRACTDuring infection,Staphylococcus aureussecretes two coagulases (Coa and von Willebrand factor binding protein [vWbp]), which, following an association with host prothrombin and fibrinogen, form fibrin clots and enable the establishment of staphylococcal disease. Within the genomes of differentS. aureusisolates, coagulase gene sequences are variable, and this has been exploited for a classification of types. We show here that antibodies directed against the variable prothrombin binding portion of coagulases confer type-specific immunity through the neutralization ofS. aureusclotting activity and protection from staphylococcal disease in mice. By combining variable portions of coagulases from North American isolates into hybrid Coa and vWbp proteins, a subunit vaccine that provided protection against challenge with different coagulase-typeS. aureusstrains in mice was derived.

scholarly journals Biochemical and Immunological Evaluation of Recombinant CS6-Derived Subunit EnterotoxigenicEscherichia coliVaccine Candidates

2019 ◽  
Vol 87 (3) ◽  
Author(s):  
Steven T. Poole ◽  
Milton Maciel ◽  
Premkumar Dinadayala ◽  
Kathleen E. Dori ◽  
Annette L. McVeigh ◽  
...  
Keyword(s):  
Immune Responses ◽  
Recombinant Proteins ◽  
Neutralizing Antibodies ◽  
Subunit Vaccine ◽  
Vaccine Strategy ◽  
Content Type ◽  
A Subunit ◽  
Folded Proteins ◽  
Immunological Evaluation

ABSTRACTCS6, a prevalent surface antigen expressed in nearly 20% of clinical enterotoxigenicEscherichia coli(ETEC) isolates, is comprised of two major subunit proteins, CssA and CssB. Using donor strand complementation, we constructed a panel of recombinant proteins of 1 to 3 subunits that contained combinations of CssA and/or CssB subunits and a donor strand, a C-terminal extension of 16 amino acids that was derived from the N terminus of either CssA or CssB. While the entire panel of recombinant proteins could be obtained as soluble, folded proteins, it was observed that the proteins possessing a heterologous donor strand, derived from the CS6 subunit different from the C-terminal subunit, had the highest degree of physical and thermal stability. Immunological characterization of the proteins, using a murine model, demonstrated that robust anti-CS6 immune responses were generated from fusions containing both CssA and CssB. Proteins containing only CssA were weakly immunogenic. Heterodimers, i.e., CssBA and CssAB, were sufficient to recapitulate the anti-CS6 immune response elicited by immunization with CS6, including the generation of functional neutralizing antibodies, as no further enhancement of the response was obtained with the addition of a third CS6 subunit. Our findings here demonstrate the feasibility of including a recombinant CS6 subunit protein in a subunit vaccine strategy against ETEC.

scholarly journals Study on coinfecting vector-borne pathogens in dogs and ticks in Rio Grande do Norte, Brazil

2014 ◽  
Vol 23 (3) ◽  
pp. 407-412 ◽  
Author(s):  
Luiz Ricardo Gonçalves ◽  
Kilder Dantas Filgueira ◽  
Silvia Maria Mendes Ahid ◽  
Josivânia Soares Pereira ◽  
André Mendes do Vale ◽  
...  
Keyword(s):  
Clinical Signs ◽  
Rio Grande ◽  
Molecular Techniques ◽  
Multiple Infections ◽  
Blood Samples ◽  
Vector Borne Diseases ◽  
Leishmania Spp ◽  
Tick Borne Disease ◽  
Vector Borne ◽  
Babesia Spp

Since dogs presenting several vector borne diseases can show none or nonspecific clinical signs depending on the phase of infection, the assessment of the particular agents involved is mandatory. The present study aimed to investigate the presence of Babesia spp., Ehrlichia spp., Anaplasma spp., Hepatozoon spp. and Leishmania spp. in blood samples and ticks, collected from two dogs from Rio Grande do Norte showing suggestive tick-borne disease by using molecular techniques. DNA of E. canis, H. canis and L. infantum were detected in blood samples and R. sanguineus ticks collected from dogs. Among all samples analyzed, two showed the presence of multiple infections with E. canis, H. canis and L. infantum chagasi. Here we highlighted the need for molecular differential diagnosis in dogs showing nonspecific clinical signs.

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