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Sample records for abortus live vaccine

  1. High-resolution melt PCR analysis for rapid identification of Chlamydia abortus live vaccine strain 1B among C. abortus strains and field isolates.

    PubMed

    Vorimore, Fabien; Cavanna, Noémie; Vicari, Nadia; Magnino, Simone; Willems, Hermann; Rodolakis, Annie; Siarkou, Victoria I; Laroucau, Karine

    2012-09-01

    We describe a novel high-resolution melt assay that clearly differentiates Chlamydia abortus live vaccine strain 1B from field C. abortus strains and field wild-type isolates based on previously described single nucleotide polymorphisms. This modern genotyping technique is inexpensive, easy to use, and less time-consuming than PCR-RFLP.

  2. 9 CFR 113.65 - Brucella Abortus Vaccine.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 9 Animals and Animal Products 1 2012-01-01 2012-01-01 false Brucella Abortus Vaccine. 113.65... Bacterial Vaccines § 113.65 Brucella Abortus Vaccine. Brucella Abortus Vaccine shall be prepared as a desiccated live culture bacterial vaccine from smooth colonial forms of the Brucella abortus...

  3. 9 CFR 113.65 - Brucella Abortus Vaccine.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 9 Animals and Animal Products 1 2014-01-01 2014-01-01 false Brucella Abortus Vaccine. 113.65... Bacterial Vaccines § 113.65 Brucella Abortus Vaccine. Brucella Abortus Vaccine shall be prepared as a desiccated live culture bacterial vaccine from smooth colonial forms of the Brucella abortus...

  4. 9 CFR 113.65 - Brucella Abortus Vaccine.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 9 Animals and Animal Products 1 2010-01-01 2010-01-01 false Brucella Abortus Vaccine. 113.65... Bacterial Vaccines § 113.65 Brucella Abortus Vaccine. Brucella Abortus Vaccine shall be prepared as a desiccated live culture bacterial vaccine from smooth colonial forms of the Brucella abortus...

  5. 9 CFR 113.65 - Brucella Abortus Vaccine.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 9 Animals and Animal Products 1 2011-01-01 2011-01-01 false Brucella Abortus Vaccine. 113.65... Bacterial Vaccines § 113.65 Brucella Abortus Vaccine. Brucella Abortus Vaccine shall be prepared as a desiccated live culture bacterial vaccine from smooth colonial forms of the Brucella abortus...

  6. 9 CFR 113.65 - Brucella Abortus Vaccine.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 9 Animals and Animal Products 1 2013-01-01 2013-01-01 false Brucella Abortus Vaccine. 113.65... Bacterial Vaccines § 113.65 Brucella Abortus Vaccine. Brucella Abortus Vaccine shall be prepared as a desiccated live culture bacterial vaccine from smooth colonial forms of the Brucella abortus...

  7. A potent Brucella abortus 2308 Δery live vaccine allows for the differentiation between natural and vaccinated infection.

    PubMed

    Zhang, Junbo; Yin, Shuanghong; Guo, Fei; Meng, Ren; Chen, Chuangfu; Zhang, Hui; Li, Zhiqiang; Fu, Qiang; Shi, Huijun; Hu, Shengwei; Ni, Wei; Li, Tiansen; Zhang, Ke

    2014-08-01

    Brucellosis is a globally distributed zoonotic disease that causes animal and human diseases. However, the current Brucella abortus vaccines (S19 and RB51) are deficient; they can cause abortion in pregnant animals. Moreover, when the vaccine S19 is used, tests cannot differentiate natural from vaccinated infection. Therefore, a safer and more potent vaccine is needed. A Brucella abortus 2308 ery promoter mutant (Δery) was constructed to overcome these drawbacks. The growth of the Δery mutant was significantly attenuated in macrophages and mice and induced high protective immunity in mice. Moreover, Δery induced an anti-Brucella-specific IgG (immunoglobulin G) response and stimulated the expression of interferon-gamma (INF-γ) and interleukin-4 (IL-4). Furthermore, the expression of EryA antigen allowed for the serological differentiation between natural and vaccinated infection in mice. These results indicate that the Δery mutant is a potential attenuated live vaccine candidate against virulent Brucella abortus 2308 (S2308) infection.

  8. Evaluation of Brucella abortus Phosphoglucomutase (pgm) Mutant as a New Live Rough-Phenotype Vaccine

    PubMed Central

    Ugalde, Juan Esteban; Comerci, Diego José; Leguizamón, M. Susana; Ugalde, Rodolfo Augusto

    2003-01-01

    Brucella abortus S19 is the vaccine most frequently used against bovine brucellosis. Although it induces good protection levels, it cannot be administered to pregnant cattle, revaccination is not advised due to interference in the discrimination between infected and vaccinated animals during immune-screening procedures, and the vaccine is virulent for humans. Due to these reasons, there is a continuous search for new bovine vaccine candidates that may confer protection levels comparable to those conferred by S19 but without its disadvantages. A previous study characterized the phenotype associated with the phosphoglucomutase (pgm) gene disruption in Brucella abortus S2308, as well as the possible role for the smooth lipopolysaccharide (LPS) in virulence and intracellular multiplication in HeLa cells (J. E. Ugalde, C. Czibener, M. F. Feldman, and R. A. Ugalde, Infect. Immun. 68:5716-5723, 2000). In this report, we analyze the protection, proliferative response, and cytokine production induced in BALB/c mice by a Δpgm deletion strain. We show that this strain synthesizes O antigen with a size of approximately 45 kDa but is rough. This is due to the fact that the Δpgm strain is unable to assemble the O side chain in the complete LPS. Vaccination with the Δpgm strain induced protection levels comparable to those induced by S19 and generated a proliferative splenocyte response and a cytokine profile typical of a Th1 response. On the other hand, we were unable to detect a specific anti-O-antigen antibody response by using the fluorescence polarization assay. In view of these results, the possibility that the Δpgm mutant could be used as a vaccination strain is discussed. PMID:14573645

  9. Immune response triggered by Brucella abortus following infection or vaccination.

    PubMed

    Dorneles, Elaine M S; Teixeira-Carvalho, Andréa; Araújo, Márcio S S; Sriranganathan, Nammalwar; Lage, Andrey P

    2015-07-17

    Brucella abortus live vaccines have been used successfully to control bovine brucellosis worldwide for decades. However, due to some limitations of these live vaccines, efforts are being made for the development of new safer and more effective vaccines that could also be used in other susceptible species. In this context, understanding the protective immune responses triggered by B. abortus is critical for the development of new vaccines. Such understandings will enhance our knowledge of the host/pathogen interactions and enable to develop methods to evaluate potential vaccines and innovative treatments for animals or humans. At present, almost all the knowledge regarding B. abortus specific immunological responses comes from studies in mice. Active participation of macrophages, dendritic cells, IFN-γ producing CD4(+) T-cells and cytotoxic CD8(+) T-cells are vital to overcome the infection. In this review, we discuss the characteristics of the immune responses triggered by vaccination versus infection by B. abortus, in different hosts.

  10. Combined vaccination of live 1B Chlamydophila abortus and killed phase I Coxiella burnetii vaccine does not destroy protection against chlamydiosis in a mouse model

    PubMed Central

    2004-01-01

    Abstract Q fever and chlamydiosis often affect ovine and caprine flocks simultaneously or successively. Combination vaccines effective against these 2 diseases would be of great value in veterinary medicine. Unfortunately, the current effective vaccines are a live vaccine for chlamydiosis and killed vaccine for Q fever. Vaccination of mice with live chlamydiosis vaccine 1B and killed phase I vaccine against Q fever at 2 points on the back at the same time produced good protection against chlamydial abortion. This suggests that it may be possible to vaccinate ewes and goats against chlamydiosis and Q fever simultaneously. PMID:15352550

  11. Cytokine responses in camels (Camelus bactrianus) vaccinated with Brucella abortus strain 19 vaccine.

    PubMed

    Odbileg, Raadan; Purevtseren, Byambaa; Gantsetseg, Dorj; Boldbaatar, Bazartseren; Buyannemekh, Tumurjav; Galmandakh, Zagd; Erdenebaatar, Janchivdorj; Konnai, Satoru; Onuma, Misao; Ohashi, Kazuhiko

    2008-02-01

    In the present study, we determined the levels of cytokines produced by camel (Camelus bactrianus) peripheral blood mononuclear cells (PBMCs) in response to live attenuated Brucella abortus (B. abortus) S19 vaccine. Seven camels were vaccinated with commercial B. abortus S19 vaccine, and their cytokine responses were determined using a real-time PCR assay. Cytokine responses to B. abortus S19 were examined at 6 hr, 48 hr and 1, 2 and 3 weeks post-vaccination. Serological tests were performed to further confirm these immune responses. The results revealed that IFN-gamma and IL-6 were upregulated during the first week post-vaccination. Low level expressions of IL-1alpha, IL-1beta, TNFalpha and IL-10 and no expression of IL-2 and IL-4 were observed compared with the control camels. The findings showed that B. abortus stimulates cell-mediated immunity by directly activating camel Th1 cells to secrete IFN-gamma. This quantification of cytokine expression in camels is essential for understanding of Camelidae disease development and protective immune responses. This is the first report of in vivo camel cytokine quantification after vaccination.

  12. Booster vaccination with safe, modified, live-attenuated mutants of Brucella abortus strain RB51 vaccine confers protective immunity against virulent strains of B. abortus and Brucella canis in BALB/c mice.

    PubMed

    Truong, Quang Lam; Cho, Youngjae; Kim, Kiju; Park, Bo-Kyoung; Hahn, Tae-Wook

    2015-11-01

    Brucella abortus attenuated strain RB51 vaccine (RB51) is widely used in prevention of bovine brucellosis. Although vaccination with this strain has been shown to be effective in conferring protection against bovine brucellosis, RB51 has several drawbacks, including residual virulence for animals and humans. Therefore, a safe and efficacious vaccine is needed to overcome these disadvantages. In this study, we constructed several gene deletion mutants (ΔcydC, ΔcydD and ΔpurD single mutants, and ΔcydCΔcydD and ΔcydCΔpurD double mutants) of RB51 with the aim of increasing the safety of the possible use of these mutants as vaccine candidates. The RB51ΔcydC, RB51ΔcydD, RB51ΔpurD, RB51ΔcydCΔcydD and RB51ΔcydCΔpurD mutants exhibited significant attenuation of virulence when assayed in murine macrophages in vitro or in BALB/c mice. A single intraperitoneal immunization with RB51ΔcydC, RB51ΔcydD, RB51ΔcydCΔcydD or RB51ΔcydCΔpurD mutants was rapidly cleared from mice within 3 weeks, whereas the RB51ΔpurD mutant and RB51 were detectable in spleens until 4 and 7 weeks, respectively. Vaccination with a single dose of RB51 mutants induced lower protective immunity in mice than did parental RB51. However, a booster dose of these mutants provided significant levels of protection in mice against challenge with either the virulent homologous B. abortus strain 2308 or the heterologous Brucella canis strain 26. In addition, these mutants were found to induce a mixed but T-helper-1-biased humoral and cellular immune response in immunized mice. These data suggest that immunization with a booster dose of attenuated RB51 mutants provides an attractive strategy to protect against either bovine or canine brucellosis.

  13. A Live Vaccine from Brucella abortus Strain 82 for Control of Cattle Brucellosis in the Russian Federation

    Technology Transfer Automated Retrieval System (TEKTRAN)

    During the first half of the 20th century, widespread regulatory efforts to control cattle brucellosis (Brucella abortus) in the Union of Soviet Socialist Republics were essentially nonexistent, and control was limited to selective test and slaughter of serologic agglutination reactors. By the 1950...

  14. Characterization of a murine model of intranasal infection suitable for testing vaccines against C. abortus.

    PubMed

    Buendía, A J; Nicolás, L; Ortega, N; Gallego, M C; Martinez, C M; Sanchez, J; Caro, M R; Navarro, J A; Salinas, J

    2007-01-15

    Mouse models have been widely used to test candidate vaccines against Chlamydophila abortus infection in mice. Although the induction of a systemic infection by endogenous or intraperitoneal inoculation is a useful tool for understanding the immune mechanism involved in the protection conferred by the vaccination, a different approach is necessary to understand other factors of the infection, such as mucosal immunity or the colonization of target organs. To test whether C. abortus intranasal model of infection in mice is a useful tool for testing vaccines in a first group of experiments mice, were infected intranasally with C. abortus to characterize the model of infection. When this model was used to test vaccines, two inactivated experimental vaccines, one of them adjuvated with QS-21 and another with aluminium hydroxide, and a live attenuated vaccine (strain 1B) were used. Non-vaccinated control mice died within the first 8 days, after displaying substantial loss of weight. Histologically, the mice showed lobar fibrinopurulent bronchointerstitial pneumonia. Prior immunization with QS-21 adjuvated vaccine or 1B vaccine presented mortality and the recipients showed a greater number of T cells in the lesions, especially CD8(+) T cells, than the control mice and mice immunized with vaccine adjuvated with aluminium hydroxide. The results confirm that the C. abortus intranasal model of infection in mice is a useful tool for testing vaccines.

  15. Brucella abortus RB51 in milk of vaccinated adult cattle.

    PubMed

    Miranda, Karina Leite; Poester, Fernando Padilla; Dorneles, Elaine Maria Seles; Resende, Thiago Magalhães; Vaz, Adil Knackfuss; Ferraz, Sandra Maria; Lage, Andrey Pereira

    2016-08-01

    The aim of this study was to evaluate the shedding of Brucella abortus in the milk of cows vaccinated with a full dose of RB51 during lactation. Eighteen cows, nine previously vaccinated with S19 as calves and nine non-vaccinated, were immunized subcutaneously with 1.3×10(10)CFU of B. abortus RB51, 30-60days after parturition. Milk samples from all animals were collected daily until day 7, and at weekly interval for the next 9 weeks after vaccination. To evaluate the shedding of B. abortus, milk samples were submitted for culture and PCR. No B. abortus was isolated from any sample tested. Only one sample, collected on first day after vaccination from a cow previously vaccinated, was faintly positive in the PCR. In conclusion, the public health hazard associated with milk consumption from cows vaccinated with RB51 in post-partum is very low, despite vaccination with the full dose and regardless of previous S19 vaccination.

  16. Ability of Brucella abortus rough vaccine strains to elicit DC and innate immunity in lung using a murine respiratory model.

    PubMed

    Surendran, Naveen; Zimmerman, Kurt; Seleem, Mohamed N; Sriranganathan, Nammalwar; Boyle, Stephen M; Hiltbold, Elizabeth M; Lawler, Heather; Heid, Bettina; Witonsky, Sharon G

    2010-10-08

    Brucella abortus strains RB51 and RB51SOD are live attenuated vaccine strains which protect mice against virulent B. abortus strain 2308 intraperitoneal challenge. By comparison, limited information is available on how Brucella vaccines stimulate pulmonary immunity against respiratory infection, another route of exposure in humans. Therefore, in this study, we assessed the ability of intranasally delivered vaccine strains RB51 and RB51SOD to induce innate immunity. Based on parameters assessed, rough strain RB51 induces a better innate immune response in lung versus strain RB51SOD. Additional studies to further delineate strain RB51's ability to stimulate DC and adaptive immunity are warranted.

  17. Vector Development for the Expression of Foreign Proteins in the Vaccine Strain Brucella abortus S19

    PubMed Central

    Comerci, Diego J.; Pollevick, Guido D.; Vigliocco, Ana M.; Frasch, Alberto C. C.; Ugalde, Rodolfo A.

    1998-01-01

    A vector for the expression of foreign antigens in the vaccine strain Brucella abortus S19 was developed by using a DNA fragment containing the regulatory sequences and the signal peptide of the Brucella bcsp31 gene. This fragment was cloned in broad-host-range plasmid pBBR4MCS, resulting in plasmid pBEV. As a reporter protein, a repetitive antigen of Trypanosoma cruzi was used. The recombinant fusion protein is stably expressed and secreted into the Brucella periplasmic space, inducing a good antibody response against the T. cruzi antigen. The expression of the repetitive antigen in Brucella neither altered its growth pattern nor generated a toxic or lethal effect during experimental infection. The application of this strategy for the generation of live recombinant vaccines and the tagging of B. abortus S19 vaccine is discussed. This is the first time that a recombinant protein has been expressed in the periplasm of brucellae. PMID:9673273

  18. Influenza Vaccine, Live Intranasal

    MedlinePlus

    ... the recombinant influenza vaccine (RIV). The nasal spray flu vaccine (live attenuated influenza vaccine or LAIV) should NOT ... to your doctor or pharmacist about the best flu vaccine option for you or your family.

  19. Immune responses of bison and efficacy after booster vaccination with Brucella abortus strain RB51

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Thirty-one bison heifers were randomly assigned to saline (control; n=7) or single vaccination (n=24) with 1010 CFU of B. abortus strain RB51 (RB51). Some vaccinated bison were randomly selected for booster vaccination with 10**10 CFU of RB51 at 11 months after initial vaccination (n=16). When comp...

  20. Therapeutic Chlamydophila abortus and C. pecorum Vaccination Transiently Reduces Bovine Mastitis Associated with Chlamydophila Infection▿

    PubMed Central

    Biesenkamp-Uhe, Carolin; Li, Yihang; Hehnen, Hans-Robert; Sachse, Konrad; Kaltenboeck, Bernhard

    2007-01-01

    Infections with Chlamydophila abortus and C. pecorum are highly prevalent in cattle and have been associated with bovine mastitis. A prospective cohort study was conducted with a herd of 140 Holstein dairy cows to investigate the influence of Chlamydophila infection on subclinical inflammation of the bovine mammary gland as characterized by somatic cell numbers in milk. PCR detection of C. abortus and low serum antibody levels against Chlamydophila spp. were significantly associated with subclinical mastitis. To examine the effect of the infection by response modification, immune perturbation was done by two subcutaneous administrations of an experimental vaccine preparation of inactivated C. abortus and C. pecorum elementary bodies. Vaccination against Chlamydophila highly significantly decreased milk somatic cell numbers, thus reducing bovine mastitis, and increased antibody levels against Chlamydophila but did not eliminate shedding of C. abortus in milk as detected by PCR. The protective effect peaked at 11 weeks after vaccination and lasted for a total of 14 weeks. Vaccination with the Chlamydophila vaccine, a mock vaccine, or a combination vaccine against bovine viral diseases highly significantly increased C. abortus shedding in milk for 1 week, presumably mediated by the vaccine adjuvant. In summary, this study shows an etiological involvement of the widespread Chlamydophila infections in bovine mastitis, a herd disease of critical importance for the dairy industry. Furthermore, this investigation shows the potential for temporary improvement of chlamydial disease by therapeutic vaccination. Chlamydophila vaccination of cattle might serve as a testing ground for vaccines against human chlamydial infections. PMID:17118976

  1. Studies on recombinant glucokinase (r-glk) protein of Brucella abortus as a candidate vaccine molecule for brucellosis.

    PubMed

    Vrushabhendrappa; Singh, Amit Kumar; Balakrishna, Konduru; Sripathy, Murali Harishchandra; Batra, Harsh Vardhan

    2014-09-29

    Brucellosis is one of the most prevalent zoonotic diseases of worldwide distribution caused by the infection of genus Brucella. Live attenuated vaccines such as B. abortus S19, B. abortus RB51 and B. melitensis Rev1 are found most effective against brucellosis infection in animals, contriving a number of serious side effects and having chances to revert back into their active pathogenic form. In order to engineer a safe and effective vaccine candidate to be used in both animals and human, a recombinant subunit vaccine molecule comprising the truncated region of glucokinase (r-glk) gene from B. abortus S19 was cloned and expressed in Escherichia coli BL21DE3 host. Female BALB/c mice immunized with purified recombinant protein developed specific antibody titer of 1:64,000. The predominant IgG2a and IgG2b isotypes signified development of Th1 directed immune responses. In vitro cell cytotoxicity assay using anti-r-glk antibodies incubated with HeLa cells showed 81.20% and 78.5% cell viability against lethal challenge of B. abortus 544 and B. melitensis 16M, respectively. The lymphocyte proliferative assay indicated a higher splenic lymphocyte responses at 25μg/ml concentration of protein which implies the elevated development of memory immune responses. In contrast to control, the immunized group of mice intra-peritoneal (I.P.) challenged with B. abortus 544 were significantly protected with no signs of necrosis and vacuolization in their liver and spleen tissue. The elevated B-cell response associated with Th1 adopted immunity, significant in vitro cell viability as well as protection afforded in experimental animals after challenge, supplemented with histopathological analysis are suggestive of r-glk protein as a prospective candidate vaccine molecule against brucellosis.

  2. Effectiveness of natural and synthetic complexes of porin and O polysaccharide as vaccines against Brucella abortus in mice.

    PubMed Central

    Winter, A J; Rowe, G E; Duncan, J R; Eis, M J; Widom, J; Ganem, B; Morein, B

    1988-01-01

    A single vaccination of mice with a complex of porin and smooth lipopolysaccharide (porin-S-LPS) extracted from virulent Brucella abortus 2308 provided significant protection (P less than 0.01 to P less than 0.001) against challenge with the same strain, equivalent to that achieved by vaccination with living attenuated B. abortus 19. The porin-S-LPS vaccine given without adjuvant or in several adjuvants (trehalose dimycolate and muramyl dipeptide; the pluronic polymer L-121 and muramyl dipeptide; or complexed with Quil A in immunostimulating complexes) provided equivalent protection. In contrast, one vaccination with porin complexed with rough LPS (porin-R-LPS) from a rough mutant of strain 2308 provided no protection with any adjuvant tested. In one experiment, two inoculations with the porin-R-LPS resulted in a low level of protection, probably owing to priming of the animals for production of O-polysaccharide-specific antibodies. However, one vaccination with rough-strain porin covalently bound to purified O polysaccharide conferred protection equal to that obtained with natural complexes of porin-S-LPS or with living strain 19. A synthetic vaccine containing long chains of O polysaccharide was more effective than one prepared with short chains. Protective vaccines caused the formation of increased concentrations of circulating O-polysaccharide-specific antibodies, although there were individual exceptions to the quantitative association between O-polysaccharide-specific antibodies and protection. Antibodies specific for porin or R-LPS were found in negligible quantities in vaccinated mice. These results provide additional evidence that the O polysaccharide will constitute an essential component of an effective subcellular vaccine against B. abortus and that O-polysaccharide-specific antibodies play an important role in protective immunity in brucellosis. PMID:2844673

  3. Influenza viral vectors expressing the Brucella OMP16 or L7/L12 proteins as vaccines against B. abortus infection

    PubMed Central

    2014-01-01

    comparable to those induced by a commercial live B. abortus 19 vaccine. Conclusion Thus, influenza vectors expressing Brucella protective antigens can be developed as novel influenza vectored vaccine against B. abortus infection. PMID:24716528

  4. Live Virus Smallpox Vaccine

    MedlinePlus

    ... Submit What's this? Submit Button The Live Virus Smallpox Vaccine Language: English Español (Spanish) Recommend on Facebook ... the vaccinia virus. Who should NOT get the smallpox vaccine? People most likely to have side effects ...

  5. Abortion and premature birth in cattle following vaccination with Brucella abortus strain RB51.

    PubMed

    Fluegel Dougherty, Amanda M; Cornish, Todd E; O'Toole, Donal; Boerger-Fields, Amy M; Henderson, Owen L; Mills, Ken W

    2013-09-01

    Brucella abortus RB51 is the vaccine strain currently licensed for immunizing cattle against brucellosis in the United States. Most cattle are vaccinated as heifer calves at 4-12 months of age. Adult cattle may be vaccinated in selected high-risk situations. Two herds of pregnant adult cattle in the brucellosis-endemic area of Wyoming were vaccinated with a standard label dose (1.0-3.4 × 10(10) organisms) of RB51. Reproductive losses in the vaccinated herds were 5.3% (herd A) and 0.6% (herd B) and included abortions, stillbirths, premature calves, and unbred cows (presumed early abortion). Brucella abortus was cultured from multiple tissues of aborted and premature calves (7/9), and from placenta. Isolates were identified as B. abortus strain RB51 by standard strain typing procedures and a species-specific polymerase chain reaction. Bronchopneumonia with intralesional bacteria and placentitis were observed microscopically. There was no evidence of involvement of other infectious or toxic causes of abortion. Producers, veterinarians, and laboratory staff should be alert to the risk of abortion when pregnant cattle are vaccinated with RB51, to potential human exposure, and to the importance of distinguishing field from vaccinal strains of B. abortus.

  6. Comparative evaluation of the protective efficacy of two formulations of a recombinant Chlamydia abortus subunit candidate vaccine in a mouse model.

    PubMed

    Pan, Qing; Pais, Roshan; Ohandjo, Adaugo; He, Cheng; He, Qing; Omosun, Yusuf; Igietseme, J U; Eko, F O

    2015-04-08

    Chlamydia abortus (C. abortus) is the causative agent of ovine enzootic abortion (OEA) and poses a zoonotic risk to pregnant women. Current live attenuated 1B vaccines are efficacious but cause disease in vaccinated animals and inactivated vaccines are only marginally protective. We tested the ability of a new C. abortus subunit vaccine candidate based on the conserved and immunogenic polymorphic membrane protein D (Pmp18D) formulated in CpG1826+FL (Fms-like tyrosine kinase 3 Ligand; Flt3L) or Vibrio cholerae ghosts (VCG) to induce innate and cross protective immunity against genital C. abortus infection. We found that delivery of rPmp18D with VCG was more effective than with CpG+FL in up-regulating the expression of molecules critically involved in T cell activation and differentiation, including MHC II, CD40, CD80, and CD86, activation of TLRs and NLRP3 inflammasome engagement, and secretion of IL-1β and TNF-α but not IL-10 and IL-4. rVCG-Pmp18D-immunized mice elicited more robust antigen-specific IFN-γ, IgA and IgG2c antibody responses compared to CpG+FL-delivered rPmp18D. Based on the number of mice with positive vaginal cultures, length of vaginal shedding, and number of inclusion forming units recovered following challenge with the heterologous C. abortus strain B577, vaccine delivery with VCG induced superior protective immunity than delivery with a combination of CpG1826 and FL, a nasal DC-targeting adjuvant. These results demonstrate that the ability of VCG to enhance protective immunity against genital C. abortus infection is superior to that of CpG+FL adjuvants.

  7. Comparative evaluation of the protective efficacy of two formulations of a recombinant Chlamydia abortus subunit candidate vaccine in a mouse model

    PubMed Central

    Pan, Qing; Pais, Roshan; Ohandjo, Adaugo; He, Cheng; He, Qing; Omosun, Yusuf; Igietseme, J. U.; Eko, F. O.

    2015-01-01

    Chlamydia abortus (C. abortus) is the causative agent of ovine enzootic abortion (OEA) and poses a zoonotic risk to pregnant women. Current live attenuated 1B vaccines are efficacious but cause disease in vaccinated animals and inactivated vaccines are only marginally protective. We tested the ability of a new C. abortus subunit vaccine candidate based on the conserved and immunogenic polymorphic membrane protein D (Pmp18D) formulated in CpG1826+FL (Fms-like tyrosine kinase 3 Ligand; Flt3L) or Vibrio cholerae ghosts (VCG) to induce innate and cross protective immunity against genital C. abortus infection. We found that delivery of rPmp18D with VCG was more effective than with CpG+FL in up-regulating the expression of molecules critically involved in T cell activation and differentiation, including MHC II, CD40, CD80, and CD86, activation of TLRs and NLRP3 inflammasome engagement, and secretion of IL-1β and TNF-α but not IL-10 and IL-4. rVCG-Pmp18D-immunized mice elicited more robust antigen-specific IFN-γ IgA and IgG2c antibody responses compared to CpG+FL-delivered rPmp18D. Based on the number of mice with positive vaginal cultures, length of vaginal shedding, and number of inclusion forming units recovered following challenge with the heterologous C. abortus strain B577, vaccine delivery with VCG induced superior protective immunity than delivery with a combination of CpG1826 and FL, a nasal DC-targeting adjuvant. These results demonstrate that the ability of VCG to enhance protective immunity against genital C. abortus infection is superior to that of CpG+FL adjuvants. PMID:25698486

  8. Vaccination of Elk (Cervus canadensis) with Brucella abortus Strain RB51 Overexpressing Superoxide Dismutase and Glycosyltransferase Genes Does Not Induce Adequate Protection against Experimental Brucella abortus Challenge

    PubMed Central

    Nol, Pauline; Olsen, Steven C.; Rhyan, Jack C.; Sriranganathan, Nammalwar; McCollum, Matthew P.; Hennager, Steven G.; Pavuk, Alana A.; Sprino, Phillip J.; Boyle, Stephen M.; Berrier, Randall J.; Salman, Mo D.

    2016-01-01

    In recent years, elk (Cervus canadensis) have been implicated as the source of Brucella abortus infection for numerous cattle herds in the Greater Yellowstone Area. In the face of environmental and ecological changes on the landscape, the range of infected elk is expanding. Consequently, the development of effective disease management strategies for wild elk herds is of utmost importance, not only for the prevention of reintroduction of brucellosis to cattle, but also for the overall health of the Greater Yellowstone Area elk populations. In two studies, we evaluated the efficacy of B. abortus strain RB51 over-expressing superoxide dismutase and glycosyltransferase for protecting elk from infection and disease caused by B. abortus after experimental infection with a virulent B. abortus strain. Our data indicate that the recombinant vaccine does not protect elk against brucellosis. Further, work is needed for development of an effective brucellosis vaccine for use in elk. PMID:26904509

  9. Vaccination of Elk (Cervus canadensis) with Brucella abortus Strain RB51 Overexpressing Superoxide Dismutase and Glycosyltransferase Genes Does Not Induce Adequate Protection against Experimental Brucella abortus Challenge.

    PubMed

    Nol, Pauline; Olsen, Steven C; Rhyan, Jack C; Sriranganathan, Nammalwar; McCollum, Matthew P; Hennager, Steven G; Pavuk, Alana A; Sprino, Phillip J; Boyle, Stephen M; Berrier, Randall J; Salman, Mo D

    2016-01-01

    In recent years, elk (Cervus canadensis) have been implicated as the source of Brucella abortus infection for numerous cattle herds in the Greater Yellowstone Area. In the face of environmental and ecological changes on the landscape, the range of infected elk is expanding. Consequently, the development of effective disease management strategies for wild elk herds is of utmost importance, not only for the prevention of reintroduction of brucellosis to cattle, but also for the overall health of the Greater Yellowstone Area elk populations. In two studies, we evaluated the efficacy of B. abortus strain RB51 over-expressing superoxide dismutase and glycosyltransferase for protecting elk from infection and disease caused by B. abortus after experimental infection with a virulent B. abortus strain. Our data indicate that the recombinant vaccine does not protect elk against brucellosis. Further, work is needed for development of an effective brucellosis vaccine for use in elk.

  10. Nucleic acid vaccination of Brucella abortus ribosomal L7/L12 gene elicits immune response.

    PubMed

    Kurar, E; Splitter, G A

    1997-12-01

    Nucleic acid vaccines provide an exciting approach for antigen presentation to the immune system. As a test of this new methodology, the immune response to the in vivo-expressed Brucella abortus ribosomal L7/12 gene in the muscle cells of mice was examined. To accomplish this goal the eukaryotic expression systems pcDNA3 and p6 were used. Single intramuscular injection of the L7/L12 gene driven by the human cytomegalovirus (CMV) promoter (pcDNA3) or bovine MHC 1 promoter (p6) resulted in intracellular expression of the B. abortus L7/L12 immunodominant protein encoded by this gene. This application facilitated directed antigen presentation to the immune system and established specific antibody and T-cell responses compared with vector only (pcDNA3) negative controls and B. abortus S19 injected positive controls. Although pcDNA3-encoded L7/L12 gene-inoculated mice possessed significant protection, p6-L7/L12 did not engender significant protection against B. abortus S2308 infection compared to positive control mice. These data suggest a promising antigen-specific response, and L7/L12 nucleic acid vaccination may be an initial step in the development of genetically engineered candidate vaccines against brucellosis. This study for the first time focuses on DNA immunization of a gene from B. abortus.

  11. Efficacy of dart or booster vaccination with strain RB51 in protecting bison against experimental Brucella abortus challenge.

    PubMed

    Olsen, S C; Johnson, C S

    2012-06-01

    This study characterized the efficacy of the Brucella abortus strain RB51 vaccine in bison when delivered by single intramuscular vaccination (hand RB51), by single pneumatic dart delivery (dart RB51), or as two vaccinations approximately 13 months apart (booster RB51) in comparison to control bison. All bison were challenged intraconjunctivally in midgestation with 10(7) CFU of B. abortus strain 2308 (S2308). Bison were necropsied and sampled within 72 h of abortion or delivery of a live calf. Compared to nonvaccinated bison, bison in the booster RB51 treatment had a reduced (P < 0.05) incidence of abortion, uterine infection, or infection in maternal tissues other than the mammary gland at necropsy. Bison in single-vaccination treatment groups (hand RB51 and dart RB51) did not differ (P > 0.05) from the control group in the incidence of abortion or recovery of S2308 from uterine, mammary, fetal, or maternal tissues at necropsy. Compared to nonvaccinated animals, all RB51 vaccination groups had reduced (P < 0.05) mean colonization or incidence of infection in at least 2 of 4 target tissues, with the booster RB51 group having reduced (P < 0.05) colonization and incidence of infection in all target tissues. Our data suggest that booster vaccination of bison with RB51 enhances protective immunity against Brucella challenge compared to single vaccination with RB51 by hand or by pneumatic dart. Our study also suggests that an initial vaccination of calves followed by booster vaccination as yearlings should be an effective strategy for brucellosis control in bison.

  12. Immunogenicity of a Multi-Epitope DNA Vaccine Encoding Epitopes from Cu–Zn Superoxide Dismutase and Open Reading Frames of Brucella abortus in Mice

    PubMed Central

    Escalona, Emilia; Sáez, Darwin; Oñate, Angel

    2017-01-01

    Brucellosis is a bacterial zoonotic disease affecting several mammalian species that is transmitted to humans by direct or indirect contact with infected animals or their products. In cattle, brucellosis is almost invariably caused by Brucella abortus. Live, attenuated Brucella vaccines are commonly used to prevent illness in cattle, but can cause abortions in pregnant animals. It is, therefore, desirable to design an effective and safer vaccine against Brucella. We have used specific Brucella antigens that induce immunity and protection against B. abortus. A novel recombinant multi-epitope DNA vaccine specific for brucellosis was developed. To design the vaccine construct, we employed bioinformatics tools to predict epitopes present in Cu–Zn superoxide dismutase and in the open reading frames of the genomic island-3 (BAB1_0260, BAB1_0270, BAB1_0273, and BAB1_0278) of Brucella. We successfully designed a multi-epitope DNA plasmid vaccine chimera that encodes and expresses 21 epitopes. This DNA vaccine induced a specific humoral and cellular immune response in BALB/c mice. It induced a typical T-helper 1 response, eliciting production of immunoglobulin G2a and IFN-γ particularly associated with the Th1 cell subset of CD4+ T cells. The production of IL-4, an indicator of Th2 activation, was not detected in splenocytes. Therefore, it is reasonable to suggest that the vaccine induced a predominantly Th1 response. The vaccine induced a statistically significant level of protection in BALB/c mice when challenged with B. abortus 2308. This is the first use of an in silico strategy to a design a multi-epitope DNA vaccine against B. abortus. PMID:28232837

  13. Immunogenicity of a Multi-Epitope DNA Vaccine Encoding Epitopes from Cu-Zn Superoxide Dismutase and Open Reading Frames of Brucella abortus in Mice.

    PubMed

    Escalona, Emilia; Sáez, Darwin; Oñate, Angel

    2017-01-01

    Brucellosis is a bacterial zoonotic disease affecting several mammalian species that is transmitted to humans by direct or indirect contact with infected animals or their products. In cattle, brucellosis is almost invariably caused by Brucella abortus. Live, attenuated Brucella vaccines are commonly used to prevent illness in cattle, but can cause abortions in pregnant animals. It is, therefore, desirable to design an effective and safer vaccine against Brucella. We have used specific Brucella antigens that induce immunity and protection against B. abortus. A novel recombinant multi-epitope DNA vaccine specific for brucellosis was developed. To design the vaccine construct, we employed bioinformatics tools to predict epitopes present in Cu-Zn superoxide dismutase and in the open reading frames of the genomic island-3 (BAB1_0260, BAB1_0270, BAB1_0273, and BAB1_0278) of Brucella. We successfully designed a multi-epitope DNA plasmid vaccine chimera that encodes and expresses 21 epitopes. This DNA vaccine induced a specific humoral and cellular immune response in BALB/c mice. It induced a typical T-helper 1 response, eliciting production of immunoglobulin G2a and IFN-γ particularly associated with the Th1 cell subset of CD4(+) T cells. The production of IL-4, an indicator of Th2 activation, was not detected in splenocytes. Therefore, it is reasonable to suggest that the vaccine induced a predominantly Th1 response. The vaccine induced a statistically significant level of protection in BALB/c mice when challenged with B. abortus 2308. This is the first use of an in silico strategy to a design a multi-epitope DNA vaccine against B. abortus.

  14. Prime-booster vaccination of cattle with an influenza viral vector Brucella abortus vaccine induces a long-term protective immune response against Brucella abortus infection.

    PubMed

    Tabynov, Kaissar; Yespembetov, Bolat; Ryskeldinova, Sholpan; Zinina, Nadezhda; Kydyrbayev, Zhailaubay; Kozhamkulov, Yerken; Inkarbekov, Dulat; Sansyzbay, Abylai

    2016-01-20

    This study analyzed the duration of the antigen-specific humoral and T-cell immune responses and protectiveness of a recently-developed influenza viral vector Brucella abortus (Flu-BA) vaccine expressing Brucella proteins Omp16 and L7/L12 and containing the adjuvant Montadine Gel01 in cattle. At 1 month post-booster vaccination (BV), both humoral (up to 3 months post-BV; GMT IgG ELISA titer 214±55 to 857±136, with a prevalence of IgG2a over IgG1 isotype antibodies) and T-cell immune responses were observed in vaccinated heifers (n=35) compared to control animals (n=35, injected with adjuvant/PBS only). A pronounced T-cell immune response was induced and maintained for 12 months post-BV, as indicated by the lymphocyte stimulation index (2.7±0.4 to 10.1±0.9 cpm) and production of IFN-γ (13.7±1.7 to 40.0±3.0 ng/ml) at 3, 6, 9, and 12 months post-BV. Prime-boost vaccination provided significant protection against B. abortus infection at 3, 6, 9 and 12 months (study duration) post-BV (7 heifers per time point; alpha=0.03-0.01 vs. control group). Between 57.1 and 71.4% of vaccinated animals showed no signs of B. abortus infection (or Brucella isolation) at 3, 6, 9 and 12 months post-BV; the severity of infection, as indicated by the index of infection (P=0.0003 to <0.0001) and rates of Brucella colonization (P=0.03 to <0.0001), was significantly lower for vaccinated diseased animals than appropriate control animals. Good protection from B. abortus infection was also observed among pregnant vaccinated heifers (alpha=0.03), as well as their fetuses and calves (alpha=0.01), for 12 months post-BV. Additionally, 71.4% of vaccinated heifers calved successfully whereas all pregnant control animals aborted (alpha=0.01). Prime-boost vaccination of cattle with Flu-BA induces an antigen-specific humoral and pronounced T cell immune response and most importantly provides good protectiveness, even in pregnant heifers, for at least 12 months post-BV.

  15. Intratracheal infection as an efficient route for testing vaccines against Chlamydia abortus in sheep.

    PubMed

    Álvarez, D; Salinas, J; Buendía, A J; Ortega, N; del Río, L; Sánchez, J; Navarro, J A; Gallego, M C; Murcia-Belmonte, A; Cuello, F; Caro, M R

    2015-09-01

    Pregnant ewes have been widely used to test vaccines against Chlamydia abortus. However, this model entails many disadvantages such as high economic costs and long periods of pregnancy. The murine model is very useful for specific studies but cannot replace the natural host for the later stages of vaccine evaluation. Therefore, a non-pregnant model of the natural host might be useful for a vaccine trial to select the best vaccine candidates prior to use of the pregnant model. With this aim, two routes of infection were assessed in young non-pregnant sheep, namely, intranasal (IN) and intratracheal (IT). In addition, groups of non-vaccinated sheep and sheep immunised with an inactivated vaccine were established to investigate the suitability of the model for testing vaccines. After the experimental infection, isolation of the microorganism in several organs, with pathological and immunohistochemical analyses, antibody production assessment and investigation by PCR of the presence of chlamydia in the vagina or rectum were carried out. Experimental IT inoculation of C. abortus induced pneumonia in sheep during the first few days post-infection, confirming the suitability of the IT route for testing vaccines in the natural host. The course of infection and the resulting pathological signs were less severe in vaccinated sheep compared with non-vaccinated animals, demonstrating the success of vaccination. IN infection did not produce evident lesions or demonstrate the presence of chlamydial antigen in the lungs and cannot be considered an appropriate model for testing vaccines.

  16. A diagnostic protocol to identify water buffaloes (Bubalus bubalis) vaccinated with Brucella abortus strain RB51 vaccine.

    PubMed

    Tittarelli, Manuela; Atzeni, Marcello; Calistri, Paolo; Di Giannatale, Elisabetta; Ferri, Nicola; Marchi, Enrico; Martucciello, Alessandra; De Massis, Fabrizio

    2015-01-01

    The use of live vaccine strain RB51 for vaccination of domestic water buffaloes (Bubalus bubalis) at risk of infection with Brucella abortus is permitted notwithstanding the plans for the eradication and only under strict veterinary control. The antibodies induced by RB51 vaccination are not detectable using conventional diagnostic techniques; therefore, it is necessary to have a specific diagnostic tool able to discriminate vaccinated from unvaccinated animals. The combination of a complement fixation test (CFT) with specific RB51 antigen (RB51-CFT) and a brucellin skin test has been demonstrated to be a reliable diagnostic system to identify single cattle (Bos taurus) vaccinated with RB51. So far, no data are available in the international scientific literature regarding the use of this test association in water buffalo. For this reason the suitability of this test combination has been evaluated in a water buffalo herd. One hundred twenty-seven animals farmed in a herd of Salerno province (Campania, Southern Italy), in the context of a presumptive unauthorized use of RB51 vaccine were chosen for this study. All tested animals resulted negative to Rose Bengal test (RBT) and complement fixation test (CFT) used for the detection of specific antibodies against Brucella field strains. Seventy-one animals (56%) developed RB51 antigen-specific CFT (RB51-CFT) antibodies against RB51 vaccine in a first sampling, while 104 animals (82%) gave positive result to a second serum sampling conducted 11 days after the intradermal inoculation of the RB51 brucellin. One hundred and seven animals (84%) showed a positive reaction to the RB51-CFT in at least 1 sampling, while 111 animals (87%) resulted positive to the RB51 brucellin skin test. Thus, analysing the results of the 3 testing in parallel, 119 animals (94%) were positive to at least 1 of the performed tests. The results suggest that the use in parallel of the RB51 brucellin skin test with RB51-CFT may represent a reliable

  17. Immune responses of elk to vaccination with Brucella abortus strain RB51.

    PubMed

    Olsen, Steven C; Kreeger, Terry J; Palmer, Mitchell V

    2002-10-01

    In a study conducted from January to August 2000, elk (Cervus elaphus) were vaccinated with Brucella abortus strain RB51 (SRB51, n = 6) or injected with 0.15 M NaCl solution (n = 3) at approximately 6 mo of age. Beginning at 2 wk and continuing to 25 wk after vaccination, SRB51-vaccinated elk had greater antibody responses (P < 0.05) to SRB51 when compared to nonvaccinated elk. Peripheral blood mononuclear cells (PBMC) from SRB51-vaccinated elk had greater (P < 0.05) proliferative responses to SRB51 at 18 wk after vaccination when compared to responses of nonvaccinated elk. Strain RB51 was recovered from blood samples of all vaccinates at 2 wk, and three of six vaccinates at 4 wk after vaccination. The SRB51 vaccine strain was recovered from the superficial cervical lymph node of all vaccinates sampled at 6 wk after vaccination. but not from lymph node samples obtained from vaccinates at 12 or 18 wk after vaccination. At 34 wk after vaccination, SRB51 was recovered from the bronchial lymph node of one of five vaccinates but not from other tissues. Strain RB51 was not recovered at any time from samples obtained from nonvaccinated elk. This study suggests that following vaccination with SRB51, elk remain bacteremic for a prolonged period of time, rapidly develop high antibody titers, and are slower to develop detectable proliferative responses in PBMC when compared to responses of cattle or bison (Bison bison).

  18. Efficacy of dart or booster vaccination with strain RB51 in protecting bison against experimental Brucella abortus challenge

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Vaccination is an effective tool for reducing the prevalence of brucellosis in natural hosts. In this study, we characterized the efficacy of the Brucella abortus strain RB51 (RB51) vaccine in bison when delivered by single intramuscular vaccination (Hand RB51), single pneumatic dart delivery (Dart ...

  19. Efficacy of single calfhood vaccination of elk with Brucella abortus strain 19

    USGS Publications Warehouse

    Roffe, T.J.; Jones, L.C.; Coffin, K.; Drew, M.L.; Sweeney, Steven J.; Hagius, S.D.; Elzer, P.H.; Davis, D.

    2004-01-01

    Brucellosis has been eradicated from cattle in the states of Wyoming, Montana, and Idaho, USA. However, free-ranging elk (Cervus elaphus) that use feedgrounds in the Greater Yellowstone Area (GYA) and bison (Bison bison) in Yellowstone and Grand Teton national parks still have high seroprevalence to the disease and have caused loss of brucellosis-free status in Wyoming. Management tools to control or eliminate the disease are limited; however, wildlife vaccination is among the methods currently used by wildlife managers in Wyoming. We conducted a controlled challenge study of single calfhood vaccination. Elk calves, caught in January and February of 1999 and 2000 and acclimated to captivity for 3 weeks, were randomly assigned to control or vaccinate groups. The vaccinate groups received Brucetta abortus vaccine strain 19 (S19) by hand-delivered intramuscular injection. Calves were raised to adulthood and bred at either 2.5 or 3.5 years of age for 2000 and 1999 captures, respectively. Eighty-nine (44 controls, 45 vaccinates) pregnant elk entered the challenge portion of the study. We challenged elk at mid-gestation with pathogenic B. abortus strain 2308 by intraconjunctival instillation. Abortion occurred in significantly more (P = 0.002) controls (42; 93%) than vaccinates (32; 71%), and vaccine protected 25% of the vaccinate group. We used Brucella culture of fetus/calf tissues to determine the efficacy of vaccination for preventing infection, and we found that the number of infected fetuses/calves did not differ between controls and vaccinates (P = 0.14). Based on these data, single calfhood vaccination with S19 has low efficacy, will likely have only little to moderate effect on Brucella prevalence in elk, and is unlikely to eradicate the disease in wildlife of the GYA.

  20. Immune responses of bison and efficacy after booster vaccination with Brucella abortus strain RB51.

    PubMed

    Olsen, S C; McGill, J L; Sacco, R E; Hennager, S G

    2015-04-01

    Thirty-one bison heifers were randomly assigned to receive saline or a single vaccination with 10(10) CFU of Brucella abortus strain RB51. Some vaccinated bison were randomly selected for booster vaccination with RB51 at 11 months after the initial vaccination. Mean antibody responses to RB51 were greater (P < 0.05) in vaccinated bison after initial and booster vaccination than in nonvaccinated bison. The proliferative responses by peripheral blood mononuclear cells (PBMC) from the vaccinated bison were greater (P < 0.05) than those in the nonvaccinated bison at 16 and 24 weeks after the initial vaccination but not after the booster vaccination. The relative gene expression of gamma interferon (IFN-γ) was increased (P < 0.05) in the RB51-vaccinated bison at 8, 16, and 24 weeks after the initial vaccination and at 8 weeks after the booster vaccination. The vaccinated bison had greater (P < 0.05) in vitro production of IFN-γ at all sampling times, greater interleukin-1β (IL-1β) production in various samplings after the initial and booster vaccinations, and greater IL-6 production at one sampling time after the booster vaccination. Between 170 and 180 days of gestation, the bison were intraconjunctivally challenged with approximately 1 × 10(7) CFU of B. abortus strain 2308. The incidences of abortion and infection were greater (P < 0.05) in the nonvaccinated bison after experimental challenge than in the bison receiving either vaccination treatment. Booster-vaccinated, but not single-vaccinated bison, had a reduced (P < 0.05) incidence of infection in fetal tissues and maternal tissues compared to that in the controls. Compared to the nonvaccinated bison, both vaccination treatments lowered the colonization (measured as the CFU/g of tissue) of Brucella organisms in all tissues, except in retropharyngeal and supramammary lymph nodes. Our study suggests that RB51 booster vaccination is an effective vaccination strategy for enhancing herd immunity against

  1. Oral vaccination with microencapsuled strain 19 vaccine confers enhanced protection against Brucella abortus strain 2308 challenge in red deer (Cervus elaphus elaphus).

    PubMed

    Arenas-Gamboa, Angela M; Ficht, Thomas A; Davis, Donald S; Elzer, Philip H; Kahl-McDonagh, Melissa; Wong-Gonzalez, Alfredo; Rice-Ficht, Allison C

    2009-10-01

    Bison (Bison bison) and elk (Cervus elaphus nelsoni) in the Greater Yellowstone Area (GYA), USA, are infected with Brucella abortus, the causative agent of bovine brucellosis, and they serve as a wildlife reservoir for the disease. Bovine brucellosis recently has been transmitted from infected elk to cattle in Montana, Wyoming, and Idaho and has resulted in their loss of brucellosis-free status. An efficacious Brucella vaccine with a delivery system suitable for wildlife would be a valuable tool in a disease prevention and control program. We evaluated Strain 19 (S19) in a sustained release vehicle consisting of alginate microspheres containing live vaccine. In a challenge study using red deer (Cervus elaphus elaphus) as a model for elk, alginate, a naturally occurring polymer combined with a protein of Fasciola hepatica vitelline protein B was used to microencapsulate S19. Red deer were orally or subcutaneously immunized with 1.5 x 10(10) colony-forming units (CFUs) using microencapsulated S19. Humoral and cellular profiles were analyzed bimonthly throughout the study. The vaccinated red deer and nonvaccinated controls were challenged 1 yr postimmunization conjunctivally with 1 x 10(9) CFUs of B. abortus strain 2308. Red deer vaccinated with oral microencapsulated S19 had a statistically significant lower bacterial tissue load compared with controls. These data indicate for the first time that protection against Brucella-challenge can be achieved by combining a commonly used vaccine with a novel oral delivery system such as alginate-vitelline protein B microencapsulation. This system is a potential improvement for efficacious Brucella-vaccine delivery to wildlife in the GYA.

  2. Brucella abortus S19 vaccine protects dairy cattle against natural infection with Brucella melitensis.

    PubMed

    van Straten, Michael; Bardenstein, Svetlana; Keningswald, Gaby; Banai, Menachem

    2016-11-21

    Brucellosis is a zoonotic disease that can cause severe illness in humans and considerable economic loss in the livestock industry. Although small ruminants are the preferential host for Brucella melitensis, this pathogen has emerged as a cause for Brucella outbreaks in cattle. S19 vaccination is implemented in many countries where B. abortus is endemic but its effectiveness against B. melitensis has not been validated. Here we show that vaccine effectiveness in preventing disease transmission between vaccinated and unvaccinated cohorts, as determined by seroconversion, was 87.2% (95% CI 69.5-94.6%). Furthermore, vaccination was associated with a reduced risk for abortion. Together, our data emphasize the role S19 vaccination could play in preventing B. melitensis outbreaks in areas where this pathogen is prevalent in small ruminant populations.

  3. Effect of Preventive Chlamydia abortus Vaccination in Offspring Development in Sheep Challenged Experimentally

    PubMed Central

    García-Seco, Teresa; Pérez-Sancho, Marta; Salinas, Jesús; Navarro, Alejandro; Díez-Guerrier, Alberto; García, Nerea; Pozo, Pilar; Goyache, Joaquín; Domínguez, Lucas; Álvarez, Julio

    2016-01-01

    Ovine enzootic abortion, caused by Chlamydia abortus, leads to important economic losses worldwide. In addition to reproductive failures, infection may impact lamb growth during the first weeks after birth, yet this effect has not been well characterized. Vaccination can help to control the disease but variable efficacy values have been described, possibly related with factors associated with the host, the vaccine, the parameter used for efficacy determination, and the challenge conditions. In this context, we evaluated the efficacy of an inactivated standard commercial vaccine and a 1/2 diluted dose in pregnant sheep challenged with C. abortus by examining multiple indicators of vaccine effect (including incidence of reproductive failures, bacterial excretion, and evolution of weight gain of viable lambs during the first month of life). Three groups of ewes [control non-vaccinated, C (n = 18); vaccinated with standard dose, SV (n = 16); and vaccinated with 1/2 dose, DV (n = 17)], were challenged approximately 90 days post-mating and tested using direct PCR (tissue samples and vaginal swabs) and ELISA (serum) until 31 days post-reproductive outcome. There were not significant differences in the proportions of reproductive failures or bacterial shedding after birth/abortion regardless the vaccination protocol. However, a beneficial effect of vaccination on offspring growth was detected in both vaccinated groups compared with the controls, with a mean increase in weight measured at 30 days of life of 1.5 and 2.5 kg (p = 0.056) and an increase in the geometric mean of the daily gain of 8.4 and 9.7% in lambs born from DV and SV ewes compared with controls, respectively. Our results demonstrate the effect of an inactivated vaccine in the development of the offspring of C. abortus-infected ewes at a standard and a diluted dose, an interesting finding given the difficulty in achieving sufficient antigen concentration in the production of enzootic

  4. Effect of Preventive Chlamydia abortus Vaccination in Offspring Development in Sheep Challenged Experimentally.

    PubMed

    García-Seco, Teresa; Pérez-Sancho, Marta; Salinas, Jesús; Navarro, Alejandro; Díez-Guerrier, Alberto; García, Nerea; Pozo, Pilar; Goyache, Joaquín; Domínguez, Lucas; Álvarez, Julio

    2016-01-01

    Ovine enzootic abortion, caused by Chlamydia abortus, leads to important economic losses worldwide. In addition to reproductive failures, infection may impact lamb growth during the first weeks after birth, yet this effect has not been well characterized. Vaccination can help to control the disease but variable efficacy values have been described, possibly related with factors associated with the host, the vaccine, the parameter used for efficacy determination, and the challenge conditions. In this context, we evaluated the efficacy of an inactivated standard commercial vaccine and a 1/2 diluted dose in pregnant sheep challenged with C. abortus by examining multiple indicators of vaccine effect (including incidence of reproductive failures, bacterial excretion, and evolution of weight gain of viable lambs during the first month of life). Three groups of ewes [control non-vaccinated, C (n = 18); vaccinated with standard dose, SV (n = 16); and vaccinated with 1/2 dose, DV (n = 17)], were challenged approximately 90 days post-mating and tested using direct PCR (tissue samples and vaginal swabs) and ELISA (serum) until 31 days post-reproductive outcome. There were not significant differences in the proportions of reproductive failures or bacterial shedding after birth/abortion regardless the vaccination protocol. However, a beneficial effect of vaccination on offspring growth was detected in both vaccinated groups compared with the controls, with a mean increase in weight measured at 30 days of life of 1.5 and 2.5 kg (p = 0.056) and an increase in the geometric mean of the daily gain of 8.4 and 9.7% in lambs born from DV and SV ewes compared with controls, respectively. Our results demonstrate the effect of an inactivated vaccine in the development of the offspring of C. abortus-infected ewes at a standard and a diluted dose, an interesting finding given the difficulty in achieving sufficient antigen concentration in the production of enzootic

  5. A rapid cycleave PCR method for distinguishing the vaccine strain Brucella abortus A19 in China.

    PubMed

    Nan, Wenlong; Zhang, Yueyong; Tan, Pengfei; Xu, Zouliang; Chen, Yuqi; Mao, Kairong; Chen, Yiping

    2016-05-01

    Brucellosis is a widespread zoonotic disease caused by Brucella spp. Immunization with attenuated vaccines has proved to be an effective method of prevention; however, it may also interfere with diagnosis. Brucella abortus strain A19, which is homologous to B. abortus strain S19, is widely used for the prevention of bovine brucellosis in China. For effective monitoring of the control of brucellosis, it is essential to distinguish A19 from field strains. Single-nucleotide polymorphism-based assays offer a new approach to such discrimination studies. In the current study, we developed a cycleave PCR assay that successfully distinguished attenuated vaccine strains A19 and S19 from 22 strains of B. abortus and 57 strains of 5 other Brucella species. The assay gave a negative reaction with 4 non-Brucella species. The minimum sensitivity of the assay, evaluated using 10-fold dilutions of chromosomal DNA, was 7.6 fg for the A19 strain and 220 fg for the single non-A19/non-S19 Brucella strain tested (B. abortus 104M). The assay was also reproducible (intra- and interassay coefficients of variation: 0.003-0.01 and 0.004-0.025, respectively). The cycleave assay gave an A19/S19-specific reaction in 3 out of 125 field serum samples, with the same 3 samples being positive in an alternative A19/S19-specific molecular assay. The cycleave assay gave a total of 102 Brucella-specific reactions (3 being the A19/S19-specific reactions), whereas an alternative Brucella-specific assay gave 92 positive reactions (all also positive in the cycleave assay). Therefore, this assay represents a simple, rapid, sensitive, and specific tool for use in brucellosis control.

  6. Molecular typing of isolates obtained from aborted foetuses in Brucella-free Holstein dairy cattle herd after immunisation with Brucella abortus RB51 vaccine in Egypt.

    PubMed

    Wareth, Gamal; Melzer, Falk; Böttcher, Denny; El-Diasty, Mohamed; El-Beskawy, Mohamed; Rasheed, Nesma; Schmoock, Gernot; Roesler, Uwe; Sprague, Lisa D; Neubauer, Heinrich

    2016-12-01

    Bovine brucellosis is endemic in Egypt in spite of application of surveillance and control measures. An increase of abortions was reported in a Holstein dairy cattle herd with 600 animals in Damietta governorate in Egypt after immunisation with Brucella (B.) abortus RB51 vaccine. Twenty one (10.6%) of 197 vaccinated cows aborted after 3 months. All aborted cows had been tested seronegative for brucellosis in the past 3 years. B. abortus was isolated from four foetuses. Conventional biochemical and bacteriological identification and polymerase chain reaction (PCR) confirmed two B. abortus biovar (bv.) 1 smooth and two B. abortus rough strains. None of the B. abortus isolates were identified as RB51. Genotyping analysis by multiple locus of variable number tandem repeats analysis based on 16 markers (MLVA-16) revealed two different profiles with low genetic diversity. B. abortus bv1 was introduced in the herd and caused abortions.

  7. Bacterial survival, lymph node pathology, and serological responses of bison (Bison bison) vaccinated with Brucella abortus strain RB51 or strain 19.

    PubMed

    Olsen, S C; Cheville, N F; Kunkle, R A; Palmer, M V; Jensen, A E

    1997-01-01

    From August 1993 to June 1994, 3 month-old bison (Bison bison) were vaccinated with Brucella abortus strain RB51 (SRB51, n = 6), strain 19 (S19, n = 3), or with saline (n = 1) and serologic responses and persistence of vaccine strains within lymph nodes were monitored. Bison vaccinated with S19 had granulomatous lymphadenitis and greater peak numbers of B. abortus than those vaccinated with SRB51. Bison vaccinated with RB51 had similar histological lesions and B. abortus were still present in lymph nodes at 16 weeks. Although antibodies against RB51 were produced, standard tube agglutination test responses of RB51-vaccinates remained negative. The histological lesions of B. abortus infections in bison were similar to those observed in cattle, but bison did not clear SRB51 as rapidly as cattle.

  8. Immune responses and safety after dart or booster vaccination of bison with Brucella abortus strain RB51.

    PubMed

    Olsen, S C; Johnson, C

    2012-05-01

    One alternative for management of brucellosis in Yellowstone National Park bison (Bison bison) is vaccination of calves and yearlings. Although Brucella abortus strain RB51 vaccination protects bison against experimental challenge, the effect of booster vaccinations was unknown. This study characterized immunologic responses after dart or booster vaccination of bison with Brucella abortus strain RB51. In two studies, 8- to 10-month-old female bison were inoculated with saline (n = 14), hand vaccinated with 1.1 × 10(10) to 2.0 × 10(10) CFU of RB51 (n = 21), or dart vaccinated with 1.8 × 10(10) CFU of RB51 (n = 7). A subgroup of hand vaccinates in study 1 was randomly selected for booster vaccination 15 months later with 2.2 × 10(10) CFU of RB51. Compared to single vaccinates, booster-vaccinated bison had greater serologic responses to RB51. However, there was a trend for antigen-specific proliferative responses of peripheral blood mononuclear cells (PBMC) from booster vaccinates to be reduced compared to responses of PBMC from single vaccinates. PBMC from booster vaccinates tended to have greater gamma interferon (IFN-γ) production than those from single vaccinates. In general, dart vaccination with RB51 induced immunologic responses similar to those of hand vaccination. All vaccinates (single hand, dart, or booster) demonstrated greater (P < 0.05) immunologic responses at various times after vaccination than nonvaccinated bison. Booster vaccination with RB51 in early gestation did not induce abortion or fetal infection. Our data suggest that booster vaccination does not induce strong anamnestic responses. However, phenotypic data on resistance to experimental challenge are required to fully assess the effect of booster vaccination on protective immunity.

  9. An influenza viral vector Brucella abortus vaccine induces good cross-protection against Brucella melitensis infection in pregnant heifers.

    PubMed

    Tabynov, Kaissar; Ryskeldinova, Sholpan; Sansyzbay, Abylai

    2015-07-17

    Brucella melitensis can be transmitted and cause disease in cattle herds as a result of inadequate management of mixed livestock farms. Ideally, vaccines against Brucella abortus for cattle should also provide cross-protection against B. melitensis. Previously we created a novel influenza viral vector B. abortus (Flu-BA) vaccine expressing the Brucella ribosomal proteins L7/L12 or Omp16. This study demonstrated Flu-BA vaccine with adjuvant Montanide Gel01 provided 100% protection against abortion in vaccinated pregnant heifers and good cross-protection of the heifers and their calves or fetuses (90-100%) after challenge with B. melitensis 16M; the level of protection provided by Flu-BA was comparable to the commercial vaccine B. abortus S19. In terms of the index of infection and colonization of Brucella in tissues, both vaccines demonstrated significant (P=0.02 to P<0.0001) protection against B. melitensis 16M infection compared to the negative control group (PBS+Montanide Gel01). Thus, we conclude the Flu-BA vaccine provides cross-protection against B. melitensis infection in pregnant heifers.

  10. Anti-chlamydial immunity in ewes conferred by vaccination with a combination of three live chlamydia, brucella and salmonella vaccines.

    PubMed

    Souriau, A; Bosseray, N; Rodolakis, A; Lantier, F; Plommet, M

    1988-07-02

    Live attenuated vaccines against Chlamydia psittaci var ovis, Brucella melitensis and Salmonella abortus ovis have previously been shown to be compatible in mice by subcutaneous administration. Immunity against challenge with virulent chlamydia was, however, slightly decreased in associations including the B melitensis Rev 1 vaccine. The chlamydia strain 1B vaccine was administered to four- to five-month-old female lambs, either alone or in combination with the B melitensis Rev1 and the S abortus ovis Rv6 vaccines. Clinical, serological and bacteriological observations demonstrated the compatibility of the three vaccines. Control, singly and triply vaccinated ewes were challenged with a virulent strain of chlamydia during their second pregnancy, 15 months after vaccination. Five of the 12 control ewes lambed normally and 10 of them were infected, as shown by the excretion of the challenge chlamydia in genital secretions. Sixteen of the 17 ewes in the triple vaccine group lambed normally and none was infected. All 12 in the single vaccine group lambed normally and three of the 12 were infected. In spite of this unusually poor protection by the single vaccine, antichlamydial immunity was clearly not decreased by the association with the two other vaccines.

  11. Improvement of the Brucella abortus B19 vaccine by its preparation in a glycerol based medium.

    PubMed

    Sangari, F J; Agüero, J; García-Lobo, J M

    1996-03-01

    The Brucella abortus B19 vaccine strain differs from other Brucella strains in its sensitivity to erythritol. However, erythritol tolerant (Eri(t)) mutants arise from sensitive cultures of B19 at high rate, and may cause persistence and/or abortion when the vaccine is inoculated on adult cattle. Twelve different batches of B19 have been examined for the presence of Eri(t) mutants. All contained Eri(t) variants at a proportion ranging from 10(-4) to 10(-6). In order to eliminate these mutants from the vaccine cultures, we have developed a minimal medium with glycerol as the sole carbon source, named MMG30. Growth of the parental strain B19 (erythritol sensitive) in this medium was fairly good compared with the growth of its Eri(t) derivatives. Culture of the 12 different batches of B19 in liquid MMG30 produced up to a thousandfold decrease in the proportion of Eri(t) mutants present in the vaccine cultures. Use of this medium to grow B19 could represent an easy and considerable improvement of the vaccine, by the reduction of the presence of potentially dangerous Eri(t) mutants.

  12. Development of a dual vaccine for prevention of Brucella abortus infection and Escherichia coli O157:H7 intestinal colonization.

    PubMed

    Iannino, Florencia; Herrmann, Claudia K; Roset, Mara S; Briones, Gabriel

    2015-05-05

    Zoonoses that affect human and animal health have an important economic impact. In the study now presented, a bivalent vaccine has been developed that has the potential for preventing the transmission from cattle to humans of two bacterial pathogens: Brucella abortus and Shiga toxin-producing Escherichia coli (STEC). A 66kDa chimeric antigen, composed by EspA, Intimin, Tir, and H7 flagellin (EITH7) from STEC, was constructed and expressed in B. abortus Δpgm vaccine strain (BabΔpgm). Mice orally immunized with BabΔpgm(EITH7) elicited an immune response with the induction of anti-EITH7 antibodies (IgA) that clears an intestinal infection of E. coli O157:H7 three times faster (t=4 days) than mice immunized with BabΔpgm carrier strain (t=12 days). As expected, mice immunized with BabΔpgm(EITH7) strain also elicited a protective immune response against B. abortus infection. A Brucella-based vaccine platform is described capable of eliciting a combined protective immune response against two bacterial pathogens with diverse lifestyles-the intracellular pathogen B. abortus and the intestinal extracellular pathogen STEC.

  13. Brucella abortus S19 and RB51 vaccine immunogenicity test: Evaluation of three mice (BALB/c, Swiss and CD-1) and two challenge strains (544 and 2308).

    PubMed

    Miranda, Karina Leite; Dorneles, Elaine Maria Seles; Pauletti, Rebeca Barbosa; Poester, Fernando Padilla; Lage, Andrey Pereira

    2015-01-15

    The aim of the present study was to evaluate the use of different mouse strains (BALB/c, Swiss and CD-1) and different challenge strains (Brucella abortus 544 and 2308) in the study of B. abortus vaccine (S19 and RB51) immunogenicity test in the murine model. No significant difference in B. abortus vaccine potency assay was found with the use of B. abortus 544 or B. abortus 2308 as challenge strain. Results of variance analysis showed an interaction between treatment and mouse strain; therefore these parameters could not be compared separately. When CD-1 groups were compared, those vaccinated showed significantly lower counts than non-vaccinated ones (P<0.05), independently of the vaccine received (S19 or RB51). Similar results were observed on BALB/c groups. However, in Swiss mouse groups, S19 was more protective than RB51 (P<0.05), which showed protection when compared to the non-vaccinated group (P<0.05). In summary, data from the present study showed that CD-1, BALB/c and Swiss mice strains, as well as both challenge strains, B. abortus strains 544 and 2308, can be used in immunogenicity tests of S19 and RB51 vaccines.

  14. Immunological assay after vaccination of goats with Brucella melitensis Rev. I and Brucella abortus 45/20 vaccines at Saudi Arabia.

    PubMed

    Taher, S A; Ewais, M A

    1997-01-01

    The living smooth Brucella melitensis Rev. I vaccine given in the normal dose (7x10(8) organism) to goats 3 to 5 months of age stimulated a marked increase in agglutinin titer. Fractionation of pools of serum by gel filtration by anion exchange chromatography, using diethylaminoethyl (DEAE -) cellulose showed that both IgM and IgG agglutinins were present from 12 to 47 days after goats were vaccinated. Only mercaptoethanol (ME)-sensitive agglutinins were detected in most goats 4 months after vaccination, but 2 of 30 goats retained ME-resistant agglutinins for the 13 1/2 - month observation period. Fractionation of serums from goats representative of these 2 types of serologic response indicated that most goats had only IgM agglutinins, whereas the 2 given goats had activity in the IgG fraction. Adult goats given Brucella abortus 42/20 adjuvant vaccine and revaccinated 5 months later developed low agglutination titers to smooth antigen, and all became test positive to the antiglobulin test. Fractionation of serum of pools taken 1 week and 8 months after revaccination indicated that antibody activity was restricted to the IgG fraction. Sera from 5 vaccinated and nonvaccinated goats which were positive by bacteriological culture examination at necropsy 31 to 47 days after goats were given conjunctival inoculation of virulent B. melitensis had antibody activity in both IgG and IgM fractions. Test positive reaction to the ME, complement-fixation (CF), and antiglobulin (AG) test were restricted to the IgG-containing fractions of serum, whereas reactions to the agglutination (STT) and the card tests appeared with either or both fractions. The effect of these findings on the choice of tests for the differentiation of vaccination response is discussed.

  15. Vaccination of adult animals with a reduced dose of Brucella abortus S19 vaccine to control brucellosis on dairy farms in endemic areas of India.

    PubMed

    Chand, Puran; Chhabra, Rajesh; Nagra, Juhi

    2015-01-01

    Bovine brucellosis is an economically important disease which seriously affects dairy farming by causing colossal losses. It can be controlled by practicing vaccination of animals with Brucella abortus S19 vaccine (S19 vaccine). In the present study, adult bovines were vaccinated on seven dairy farms with a reduced dose of S19 vaccine to control brucellosis. Serological screening of adult animals (N = 1,082) by Rose Bengal test (RBT) and ELISA prior to vaccination revealed the presence and absence of brucellosis on five and two farms, respectively. The positive animals (N = 171) were segregated and those which tested negative (N = 911) were vaccinated by conjunctival route with a booster after 4 months. The conjunctival vaccination induced weak antibody response in animals, which vanished within a period of 9 to 12 weeks. Abortion in 12 animals at various stages of pregnancy and post-vaccination was recorded, but none was attributed to S19 vaccine. However, virulent B. abortus was incriminated in six heifers, and the cause of abortion could not be established in six animals. The six aborted heifers perhaps acquired infection through in utero transmission or from the environment which remained undetected until abortion. These findings suggested that vaccination of adult animals with a reduced dose of S19 vaccine by conjunctival route did not produce adverse effects like abortion in pregnant animals and persistent vaccinal antibody titers, which are the major disadvantages of subcutaneous vaccination of adult animals.

  16. Biosafety of parenteral Brucella abortus RB51 vaccine in bison calves

    USGS Publications Warehouse

    Roffe, T.J.; Olsen, S.C.; Gidlewski, T.; Jensen, A.E.; Palmer, M.V.; Huber, R.

    1999-01-01

    Vaccination is considered among the primary management tools for reducing brucellosis prevalence in Greater Yellowstone Area (GYA) ungulates. Before their use, however, vaccine safety and efficacy must be demonstrated. Twenty-seven female bison (Bison bison) calves (approx 5 months old) were vaccinated with Brucella abortus Strain RB51 (1.5 x 1010 colony forming units [CFU], subcutaneously) as part of routine management. We assessed the persistence, pathology, shedding, and transmission associated with RB51 by serial necropsy, bacteriology, histopathology, and serology of 20 of these 27 vaccinated calves, and RB51 serology of 10 nonvaccinated, commingling adult females. With the exception of 1 calf, RB51 dot-blot titers at necropsy were <1:80. Strain RB51 was cultured from lymph nodes in 4 of 4 calves at 14 weeks postvaccination (PV), 4 of 4 calves at 18 weeks PV, 1 of 4 calves at 22 weeks PV, 3 of 4 at 26 weeks PV, and 0 of 4 calves at 30 weeks PV. No gross lesions were observed. Mild histologic changes occurred only in a few draining lymph nodes early in sampling. Adverse clinical effects were not observed in vaccinates. Swabs from nasopharynx, conjunctiva, rectum, and vagina were uniformly culture negative for RB51. Strain RB51 dot-blot assays of bison cows were negative at a 1:20 dilution at 26 weeks PV. Our results suggest that RB51 persists longer in bison calves than in domestic cattle and is systemically distributed within lymphatic tissues. However, bison apparently clear the RB51 vaccine strain without shedding, transmission, or significant adverse reactions.

  17. Effectiveness of Brucella abortus Strain 19 single calfhood vaccination in elk (Cervus elaphus)

    USGS Publications Warehouse

    Roffe, Thomas J.; Jones, Lee C.; Coffin, Kenneth; Sweeney, Steven J.; Williams, Beth; Quist, Charlotte

    2002-01-01

    Brucellosis in Greater Yellowstone Area (GYA) bison and elk has been a source of controversy and focus of the Greater Yellowstone Interagency Brucellosis Committee (GYIBC) for years. Brucellosis has been eradicated from cattle in the 3 states of Wyoming, Montana, and Idaho and all three states currently are classified as “brucellosis free” with regard to livestock. Yet free-ranging elk that attend feedgrounds in the GYA, and bison in Yellowstone and Grand Teton National Parks, still have high seroprevalence to the disease and are viewed as a threat to the state-federal cooperative national brucellosis eradication program. Recently, cattle in eastern Idaho were found infected with brucellosis and transmission was apparently from fed elk. The GYIBC, formed of state and federal agencies involved in wildlife and livestock management in the 3 states, has committed to eventual elimination of the disease from wildlife. Management tools to control or eliminate the disease are limited; however, wildlife vaccination is one of the methods currently employed. Effective wildlife vaccination depends on dose efficacy, deliverability, and safety to non-targeted species. We commenced a single-dose efficacy study of vaccine Brucella abortus strain 19 (S19) in elk in 1999.

  18. Comparison between Immunization Routes of Live Attenuated Salmonella Typhimurium Strains Expressing BCSP31, Omp3b, and SOD of Brucella abortus in Murine Model

    PubMed Central

    Kim, Won K.; Moon, Ja Y.; Kim, Suk; Hur, Jin

    2016-01-01

    Live, attenuated Salmonella Typhimurium vaccine candidate expressing BCSP31, Omp3b, and SOD proteins of Brucella abortus was constructed. Thirty BALB/c mice were divided equally into three groups, Group A, were intraperitoneally (IP) inoculated with 100 μl of approximately 1.2 × 106 colony-forming units (CFUs)/ml of the Salmonella containing vector only in 100 μl as a control. And groups B and C mice were orally and IP immunized with approximately 1.2 × 109 CFU/ml of the mixture of three delivery strains in 10 μl and IP immunized with approximately 1.2 × 106 CFU/ml of the mixture in 100 μl, respectively. The serum IgG, TNF-α and IFN-γ concentrations in groups B (except Omp3b) and C were significantly higher than those in group A. Following challenge with B. abortus strain 544; challenge strain was detected <103 CFU from the spleen of all mice of group C. These results suggest that IP immunization with the mixture of the vaccine candidate can induce immune responses, and can effectively protect mice against brucellosis. PMID:27148232

  19. Novel vector vaccine against Brucella abortus based on influenza A viruses expressing Brucella L7/L12 or Omp16 proteins: evaluation of protection in pregnant heifers.

    PubMed

    Tabynov, Kaissar; Yespembetov, Bolat; Sansyzbay, Abylai

    2014-10-14

    The present study provides the first information about the protection of a novel influenza viral vector vaccine expressing the Brucella proteins ribosomal L7/L12 or Omp16 containing the adjuvant Montanide Gel01 in pregnant heifers. Immunization of pregnant heifers was conducted via the conjunctival (n=10) or subcutaneous (n=10) route using cross prime and booster vaccination schedules at an interval of 28 days. The vector vaccine was evaluated in comparison with positive control groups vaccinated with Brucella abortus S19 (n=10) or B. abortus RB51 (n=10) and a negative (PBS+Montanide Gel01; n=10) control group. Via both the conjunctival or subcutaneous route, evaluation of protectiveness against abortion, effectiveness of vaccination and index of infection (in heifers and their fetuses or calves) demonstrated the vector vaccine provided good protection against B. abortus 544 infection compared to the negative control group (PBS+Montanide Gel01) and comparable protection to commercial vaccines B. abortus S19 or B. abortus RB51.

  20. Immune responses and protection against experimental challenge after vaccination of bison with Brucella abortus strains RB51 or RB51 overexpressing superoxide dismutase and Glycosyltransferase genes

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Vaccination is a tool that could be beneficial in managing the high prevalence of brucellosis in free-ranging bison in Yellowstone National Park. In this study, we characterized immunologic responses and protection against experimental challenge after vaccination of bison with Brucella abortus stra...

  1. Serological response to administration of Brucella abortus strain RB51 vaccine in beef and dairy heifers, using needle-free and standard needle-based injection systems

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The purpose of this study was to compare immunologic responses of heifers vaccinated with 10**10 colony-forming units (CFU) of Brucella abortus strain RB51 (SRB51) by standard needle-and-syringe system or a needle-free injection system. Heifers were randomly assigned to control and vaccination gro...

  2. Influence of Brucella abortus lipopolysaccharide as an adjuvant on the immunogenicity of HPV-16 L1VLP vaccine in mice.

    PubMed

    Kianmehr, Zahra; Soleimanjahi, Hoorieh; Ardestani, Susan Kaboudanian; Fotouhi, Fatemeh; Abdoli, Asghar

    2015-04-01

    Brucella abortus lipopolysaccharide (LPS) has less toxicity and no pyrogenic properties in comparison with other bacterial LPS. It is a toll-like receptor 4 agonist and has been shown to have the potential use as a vaccine adjuvant. In this study, the immunostimulatory properties of LPS from smooth and rough strains of B. abortus (S19 and RB51) as adjuvants were investigated for the human papillomavirus type 16 (HPV16) L1 virus-like particles (L1VLPs) vaccines. C57BL/6 mice were immunized subcutaneously three times either with HPV-16 L1VLPs alone, or in combination with smooth LPS (S-LPS), rough LPS (R-LPS), aluminum hydroxide or a mixture of them as adjuvant. The humoral immunity was evaluated by measuring the specific and total IgG levels, and also the T-cell immune response of mice was evaluated by measuring different cytokines such as IFN-γ, TNF-α, IL-4, IL-10 and IL-17. Results showed that serum anti-HPV16 L1VLP IgG antibody titers was significantly higher in mice immunized with a combination of VLPs and R-LPS or S-LPS compared with other immunized groups. Co-administration of HPV-16 L1VLPs with R-LPS elicited the highest levels of splenocytes cytokines (IFN-γ, IL-4, IL-17 and TNF-α) and also effectively induced improvement of a Th1-type cytokine response characterized with a high ratio of IFN-γ/IL-10. The data indicate that B. abortus LPS particularly RB51-LPS enhances the immune responses to HPV-16 L1VLPs and suggests its potential as an adjuvant for the development of a potent prophylactic HPV vaccine and other candidate vaccines.

  3. A repA-based ELISA for discriminating cattle vaccinated with Brucella suis 2 from those naturally infected with Brucella abortus and Brucella melitensis.

    PubMed

    Wang, Jing-Yu; Wu, Ning; Liu, Wan-Hua; Ren, Juan-Juan; Tang, Pan; Qiu, Yuan-Hao; Wang, Chi-Young; Chang, Ching-Dong; Liu, Hung-Jen

    2014-01-01

    The commonest ways of diagnosing brucellosis in animals include the Rose-Bengal plate agglutination test, the buffered plate agglutination test (BPA), the slide agglutination test, the complement fixation test, and the indirect enzyme linked immunosorbent assay (I-ELISA). However, these methods cannot discriminate the Brucella vaccine strain (Brucella suis strain 2; B. suis S2) from naturally acquired virulent strains. Of the six common Brucella species, Brucella melitensis, Brucella abortus, and B. suis are the commonest species occurring in China. To develop an ELISA assay that can differentiate between cows inoculated with B. suis S2 and naturally infected with B. abortus and B. melitensis, genomic sequences from six Brucella spp. (B. melitensis, B. abortus, B. suis, Brucella canis, Brucella neotomae and Brucella ovis) were compared using Basic Local Alignment Search Tool software. One particular gene, the repA-related gene, was found to be a marker that can differentiate B. suis from B. abortus and B. melitensis. The repA-related gene of B. suis was PCR amplified and subcloned into the pET-32a vector. Expressed repA-related protein was purified and used as an antigen. The repA-based ELISA was optimized and used as specific tests. In the present study, serum from animals inoculated with the B. suis S2 vaccine strain had positive repA-based ELISA results. In contrast, the test-positive reference sera against B. abortus and B. melitensis had negative repA-based ELISA results. The concordance rate between B. abortus antibody-negative (based on the repA-based ELISA) and the Brucella gene-positive (based on the 'Bruce ladder' multiplex PCR) was 100%. Therefore, the findings suggest that the repA-based ELISA is a useful tool for differentiating cows vaccinated with the B. suis S2 and naturally infected with B. abortus and B. melitensis.

  4. Serological profile of buffalo (Bubalus bubalis) female calves vaccinated with standard Brucella abortus strain 19 vaccine using rose bengal, 2-mercaptoethanol and complement fixation tests.

    PubMed

    Nardi, G Júnior; Ribeiro, M G; Jorge, A M; Megid, J; Silva, L M P

    2012-03-01

    The serological profiles of 21 female buffaloes vaccinated between 3 and 8 months of age using Brucella abortus strain 19 (S19) were evaluated by rose bengal (RBT), 2-mercaptoethanol (2ME) and complement fixation (CFT) tests. The serum strains were collected in day zero, 15, 30, 45, 60th days and subsequently to each 30 months, until 720th day after vaccination. No animal showed reaction in day zero. In 15th day above 95% of animals revealed reaction in all tests. All the animals presented absence of reactions in CFT, RBT and 2ME tests at 270, 300 and 360 days after vaccination, respectively. Our finding highlighted early response in CFT compared than other conventional agglutination tests. None of animals presented oscillation of titers or reactions in any test after 360 day of study, which enables the use of these tests after this period without interference of antibodies from S19 vaccine origin between 3 and 8 months in buffalo heifers.

  5. Experimental infection of nontarget species of rodents and birds with Brucella abortus strain RB51 vaccine

    USGS Publications Warehouse

    Januszewski, M.C.; Olsen, S.C.; McLean, R.G.; Clark, L.; Rhyan, Jack C.

    2001-01-01

    The Brucella abortus vaccine strain RB51 (SRB51) is being considered for use in the management of bnucellosis in wild bison (Bison bison) and elk (Cervus elaphus) populations in the Greater Yellowstone Area (USA). Evaluation of the vaccines safety in non-target species was considered necessary prior to field use. Between June 1998 and December 1999, ground squirrels (Spermophilus richardsonii, n = 21), deer mice (Peromyscus maniculatus, n = 14), prairie voles (Microtus ochrogaster, n = 21), and ravens (Corvus corax, n = 13) were orally inoculated with SRB51 or physiologic saline. Oral and rectal swabs and blood samples were collected for bacteriologic evaluation. Rodents were necropsied at 8 to 10 wk and 12 to 21 wk post inoculation (PI), and ravens at 7 and 11 wk PI. Spleen, liver and reproductive tissues were collected for bacteriologic and histopathologic evaluation. No differences in clinical signs, appetite, weight loss or gain, or activity were observed between saline- and SRB51-inoculated animals in all four species. Oral and rectal swabs from all species were negative throughout the study. In tissues obtained from SRB51-inoculated animals, the organism was isolated from six of seven (86%) ground squirrels, one of six (17%) deer mice, none of seven voles, and one of five (20%) ravens necropsied at 8, 8, 10, and 7 wk PI, respectively. Tissues from four of seven (57%) SRB51-inoculated ground squirrels were culture positive for the organism 12 wk PI; SRB51 was not recovered from deer mice, voles. or ravens necropsied 12, 21, or 11 wk, respectively, PI. SRB51 was not recovered from saline-inoculated ground squirrels, deer mice, or voles at any time but was recovered from one saline-inoculated raven at necropsy, 7 wk PI, likely attributable to contact with SRB51-inoculated ravens in an adjacent aviary room. Spleen was time primary tissue site of colonization in ground squirrels, followed by the liver and reproductive organs. The results indicate oral exposure to

  6. Immune Response of Calves Vaccinated with Brucella abortus S19 or RB51 and Revaccinated with RB51.

    PubMed

    Dorneles, Elaine M S; Lima, Graciela K; Teixeira-Carvalho, Andréa; Araújo, Márcio S S; Martins-Filho, Olindo A; Sriranganathan, Nammalwar; Al Qublan, Hamzeh; Heinemann, Marcos B; Lage, Andrey P

    2015-01-01

    Brucella abortus S19 and RB51 strains have been successfully used to control bovine brucellosis worldwide; however, currently, most of our understanding of the protective immune response induced by vaccination comes from studies in mice. The aim of this study was to characterize and compare the immune responses induced in cattle prime-immunized with B. abortus S19 or RB51 and revaccinated with RB51. Female calves, aged 4 to 8 months, were vaccinated with either vaccine S19 (0.6-1.2 x 1011 CFU) or RB51 (1.3 x 1010 CFU) on day 0, and revaccinated with RB51 (1.3 x 1010 CFU) on day 365 of the experiment. Characterization of the immune response was performed using serum and peripheral blood mononuclear cells. Blood samples were collected on days 0, 28, 210, 365, 393 and 575 post-immunization. Results showed that S19 and RB51 vaccination induced an immune response characterized by proliferation of CD4+ and CD8+ T-cells; IFN-ɣ and IL-17A production by CD4+ T-cells; cytotoxic CD8+ T-cells; IL-6 secretion; CD4+ and CD8+ memory cells; antibodies of IgG1 class; and expression of the phenotypes of activation in T-cells. However, the immune response stimulated by S19 compared to RB51 showed higher persistency of IFN-ɣ and CD4+ memory cells, induction of CD21+ memory cells and higher secretion of IL-6. After RB51 revaccination, the immune response was chiefly characterized by increase in IFN-ɣ expression, proliferation of antigen-specific CD4+ and CD8+ T-cells, cytotoxic CD8+ T-cells and decrease of IL-6 production in both groups. Nevertheless, a different polarization of the immune response, CD4+- or CD8+-dominant, was observed after the booster with RB51 for S19 and RB51 prime-vaccinated animals, respectively. Our results indicate that after prime vaccination both vaccine strains induce a strong and complex Th1 immune response, although after RB51 revaccination the differences between immune profiles induced by prime-vaccination become accentuated.

  7. Vaccination with recombinant Semliki Forest virus particles expressing translation initiation factor 3 of Brucella abortus induces protective immunity in BALB/c mice.

    PubMed

    Cabrera, Alex; Sáez, Darwin; Céspedes, Sandra; Andrews, Edilia; Oñate, Angel

    2009-01-01

    Recombinant replicons of Semliki Forest virus (SFV) can be used to induce high-level, transient expression of heterologous proteins in vivo. We constructed infectious but replication-deficient SFV particles carrying recombinant RNA encoding the Brucella abortus translation initiation factor 3 (IF3). The recombinant SFV particles (SFV-IF3 particles) were then evaluated for their ability to induce immune responses and to protect BALB/c mice against a challenge with B. abortus 2308 following vaccination. Animals inoculated with SFV-IF3 developed IF3-specific IgM antibodies at day 14 post-immunization. In vitro stimulation of splenocytes from vaccinated mice with either recombinant IF3 (rIF3) or crude Brucella protein extracts resulted in a T-cell proliferative response and induction of interferon gamma secretion, but not interleukin-4. In addition, mice immunized with SFV-IF3 exhibited a significant level of resistance against challenge with the virulent B. abortus strain 2308 (P<0.01). These findings indicate that an SFV-based vector carrying RNA encoding Brucella IF3 has potential for use as a vaccine to induce protection against B. abortus infections.

  8. Live attenuated vaccines for invasive Salmonella infections

    PubMed Central

    Tennant, Sharon M.; Levine, Myron M.

    2015-01-01

    Salmonella enterica serovar Typhi produces significant morbidity and mortality worldwide despite the fact that there are licensed S. Typhi vaccines available. This is primarily due to the fact that these vaccines are not used in the countries that most need them. There is growing recognition that an effective invasive Salmonella vaccine formulation must also prevent infection due to other Salmonella serovars. We anticipate that a multivalent vaccine that targets the following serovars will be needed to control invasive Salmonella infections worldwide: S. Typhi, S. Paratyphi A, S. Paratyphi B (currently uncommon but may become dominant again), S. Typhimurium, S. Enteritidis and S. Choleraesuis (as well as other Group C Salmonella). Live attenuated vaccines are an attractive vaccine formulation for use in developing as well as developed countries. Here, we describe the methods of attenuation that have been used to date to create live attenuated Salmonella vaccines and provide an update on the progress that has been made on these vaccines. PMID:25902362

  9. Live attenuated vaccines for invasive Salmonella infections.

    PubMed

    Tennant, Sharon M; Levine, Myron M

    2015-06-19

    Salmonella enterica serovar Typhi produces significant morbidity and mortality worldwide despite the fact that there are licensed Salmonella Typhi vaccines available. This is primarily due to the fact that these vaccines are not used in the countries that most need them. There is growing recognition that an effective invasive Salmonella vaccine formulation must also prevent infection due to other Salmonella serovars. We anticipate that a multivalent vaccine that targets the following serovars will be needed to control invasive Salmonella infections worldwide: Salmonella Typhi, Salmonella Paratyphi A, Salmonella Paratyphi B (currently uncommon but may become dominant again), Salmonella Typhimurium, Salmonella Enteritidis and Salmonella Choleraesuis (as well as other Group C Salmonella). Live attenuated vaccines are an attractive vaccine formulation for use in developing as well as developed countries. Here, we describe the methods of attenuation that have been used to date to create live attenuated Salmonella vaccines and provide an update on the progress that has been made on these vaccines.

  10. [Escherichia coli R live vaccine Suicolplex "Dessau"].

    PubMed

    Michael-Meese, M; Klie, H; Schöll, W

    1980-01-01

    Immunisation of pregnant sows prior to parturition has long proved to be a good method to forestall coli dysentery in piglets before weaning. Inactivated vaccines of the pathogenetically important E. coli serogroups with and without adjuvant so far were primarily used at international level. A vaccine of that kind has become available in the GDR more than eight years ago. Its name is Coliporc "Dessau". A live vaccine has been developed from two R-mutants at the authors' institute. The effectiveness of that live vaccine on laboratory animals and in field experiments is reported in this paper together with possibilities of differential diagnosis to distinguish wild strains from the mutants. The live vaccine was commercially registered under the name of Suicolpex "Dessau", in spring 1976.

  11. Comparative genomic analysis of Brucella abortus vaccine strain 104M reveals a set of candidate genes associated with its virulence attenuation.

    PubMed

    Yu, Dong; Hui, Yiming; Zai, Xiaodong; Xu, Junjie; Liang, Long; Wang, Bingxiang; Yue, Junjie; Li, Shanhu

    2015-01-01

    The Brucella abortus strain 104M, a spontaneously attenuated strain, has been used as a vaccine strain in humans against brucellosis for 6 decades in China. Despite many studies, the molecular mechanisms that cause the attenuation are still unclear. Here, we determined the whole-genome sequence of 104M and conducted a comprehensive comparative analysis against the whole genome sequences of the virulent strain, A13334, and other reference strains. This analysis revealed a highly similar genome structure between 104M and A13334. The further comparative genomic analysis between 104M and A13334 revealed a set of genes missing in 104M. Some of these genes were identified to be directly or indirectly associated with virulence. Similarly, a set of mutations in the virulence-related genes was also identified, which may be related to virulence alteration. This study provides a set of candidate genes associated with virulence attenuation in B.abortus vaccine strain 104M.

  12. Vaccination of elk (Cervus canadensis) with Brucella abortus strain RB51 overexpressing superoxide dismutase and glycosyltransferase genes does not induce adequate protection against experimental brucella abortus challenge

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In recent years, elk (Cervus canadensis) have been implicated as the source of Brucella abortus infection for numerous cattle herds in the Greater Yellowstone Area (GYA). In the face of environmental and ecological changes on the landscape, the range of infected elk is expanding. Consequently, the d...

  13. DETECTION OF Leptospira spp. AND Brucella abortus ANTIBODIES IN FREE-LIVING JAGUARS (Panthera onca) IN TWO PROTECTED AREAS OF NORTHERN PANTANAL, BRAZIL

    PubMed Central

    ONUMA, Selma Samiko Miyazaki; KANTEK, Daniel Luis Zanella; CRAWSHAW, Peter Gransden; MORATO, Ronaldo Gonçalves; MAY-JÚNIOR, Joares Adenilson; de MORAIS, Zenaide Maria; FERREIRA, José Soares; de AGUIAR, Daniel Moura

    2015-01-01

     This study aimed to assess the exposure of free-living jaguars (Panthera onca) to Leptospira spp. and Brucella abortus in two conservation units in the Pantanal of Mato Grosso, Brazil. The presence of antibodies in blood samples of eleven jaguars was investigated using autochthonous antigens isolated in Brazil added to reference antigen collection applied to diagnosis of leptospirosis by Microscopic Agglutination Test (MAT). The Rose Bengal test was applied for B. abortus antibodies. Two (18.2%) jaguars were seroreactive for the Leptospira spp. antigen and the serovar considered as most infective in both animals was a Brazilian isolate of serovar Canicola (L01). All jaguars were seronegative for B. abortus. These data indicate that the inclusion of autochthonous antigens in serological studies can significantly increase the number of reactive animals, as well as modify the epidemiological profile of Leptospira spp. infection. PMID:25923900

  14. Detection of Leptospira spp. and Brucella abortus antibodies in free-living jaguars (Panthera onca) in two protected areas of northern Pantanal, Brazil.

    PubMed

    Onuma, Selma Samiko Miyazaki; Kantek, Daniel Luis Zanella; Crawshaw Júnior, Peter Gransden; Morato, Ronaldo Gonçalves; May-Júnior, Joares Adenilson; Morais, Zenaide Maria de; Ferreira Neto, José Soares; Aguiar, Daniel Moura de

    2015-01-01

    This study aimed to assess the exposure of free-living jaguars (Panthera onca) to Leptospira spp. and Brucella abortus in two conservation units in the Pantanal of Mato Grosso, Brazil. The presence of antibodies in blood samples of eleven jaguars was investigated using autochthonous antigens isolated in Brazil added to reference antigen collection applied to diagnosis of leptospirosis by Microscopic Agglutination Test (MAT). The Rose Bengal test was applied for B. abortus antibodies. Two (18.2%) jaguars were seroreactive for the Leptospira spp. antigen and the serovar considered as most infective in both animals was a Brazilian isolate of serovar Canicola (L01). All jaguars were seronegative for B. abortus. These data indicate that the inclusion of autochthonous antigens in serological studies can significantly increase the number of reactive animals, as well as modify the epidemiological profile of Leptospira spp. infection.

  15. Influenza (Flu) vaccine (Live, Intranasal): What you need to know

    MedlinePlus

    ... is taken in its entirety from the CDC Influenza Live, Intranasal Flu Vaccine Information Statement (VIS): www.cdc.gov/vaccines/ ... flulive.html . CDC review information for Live, Intranasal Influenza VIS: Vaccine Information Statement Influenza Page last reviewed: ...

  16. MLVA genotyping of Brucella melitensis and Brucella abortus isolates from different animal species and humans and identification of Brucella suis vaccine strain S2 from cattle in China.

    PubMed

    Jiang, Hai; Wang, Heng; Xu, Liqing; Hu, Guiying; Ma, Junying; Xiao, Pei; Fan, Weixing; Di, Dongdong; Tian, Guozhong; Fan, Mengguang; Mi, Jingchuan; Yu, Ruiping; Song, Litao; Zhao, Hongyan; Piao, Dongri; Cui, Buyun

    2013-01-01

    In China, brucellosis is an endemic disease and the main sources of brucellosis in animals and humans are infected sheep, cattle and swine. Brucella melitensis (biovars 1 and 3) is the predominant species, associated with sporadic cases and outbreak in humans. Isolates of B. abortus, primarily biovars 1 and 3, and B. suis biovars 1 and 3 are also associated with sporadic human brucellosis. In this study, the genetic profiles of B. melitensis and B. abortus isolates from humans and animals were analyzed and compared by multi-locus variable-number tandem-repeat analysis (MLVA). Among the B. melitensis isolates, the majority (74/82) belonged to MLVA8 genotype 42, clustering in the 'East Mediterranean' group. Two B. melitensis biovar 1 genotype 47 isolates, belonging to the 'Americas' group, were recovered; both were from the Himalayan blue sheep (Pseudois nayaur, a wild animal). The majority of B. abortus isolates (51/70) were biovar 3, genotype 36. Ten B. suis biovar 1 field isolates, including seven outbreak isolates recovered from a cattle farm in Inner Mongolia, were genetically indistinguishable from the vaccine strain S2, based on MLVA cluster analysis. MLVA analysis provided important information for epidemiological trace-back. To the best of our knowledge, this is the first report to associate Brucella cross-infection with the vaccine strain S2 based on molecular comparison of recovered isolates to the vaccine strain. MLVA typing could be an essential assay to improve brucellosis surveillance and control programs.

  17. Protection efficacy of the Brucella abortus ghost vaccine candidate lysed by the N-terminal 24-amino acid fragment (GI24) of the 36-amino acid peptide PMAP-36 (porcine myeloid antimicrobial peptide 36) in murine models

    PubMed Central

    KWON, Ae Jeong; MOON, Ja Young; KIM, Won Kyong; KIM, Suk; HUR, Jin

    2016-01-01

    Brucella abortus cells were lysed by the N-terminal 24-amino acid fragment (GI24) of the 36-amino acid peptide PMAP-36 (porcine myeloid antimicrobial peptide 36). Next, the protection efficacy of the lysed fragment as a vaccine candidate was evaluated. Group A mice were immunized with sterile PBS, group B mice were intraperitoneally (ip) immunized with 3 × 108 colony-forming units (CFUs) of B. abortus strain RB51, group C mice were immunized ip with 3 × 108 cells of the B. abortus vaccine candidate, and group D mice were orally immunized with 3 × 109 cells of the B. abortus vaccine candidate. Brucella lipopolysaccharide (LPS)-specific serum IgG titers were considerably higher in groups C and D than in group A. The levels of interleukin (IL)-4, IL-10, tumor necrosis factor alpha (TNF-α) and interferon gamma (IFN-γ) were significantly higher in groups B–D than in group A. After an ip challenge with B. abortus 544, only group C mice showed a significant level of protection as compared to group A. Overall, these results show that ip immunization with a vaccine candidate lysed by GI24 can effectively protect mice from systemic infection with virulent B. abortus. PMID:27349900

  18. The unexpected discovery of Brucella abortus Buck 19 vaccine in goats from Ecuador underlines the importance of biosecurity measures.

    PubMed

    Ron-Román, Jorge; Berkvens, Dirk; Barzallo-Rivadeneira, Daniela; Angulo-Cruz, Alexandra; González-Andrade, Pablo; Minda-Aluisa, Elizabeth; Benítez-Ortíz, Washington; Brandt, Jef; Rodríguez-Hidalgo, Richar; Saegerman, Claude

    2017-03-01

    Very few, mostly old, and only preliminary serological studies of brucellosis in goats exist in Ecuador. In order to assess the current epidemiological situation, we performed a cross-sectional serological study in the goat populations of Carchi (n = 160 animals), Pichincha (n = 224 animals), and Loja provinces (n = 2024 animals). Only two positive serological results (RB negative and SAT-EDTA ≥400 IU/ml) were obtained in lactating goats from the same farm in Quito (Pichincha province). Additionally, milk was sampled from 220 animals in Pichincha province. The present study indicates a low apparent prevalence in Pichincha province and absence in Carchi and Loja provinces. A total of 25 positive milk ring tests (MRT) were obtained in Pichincha province yielding a prevalence of MRT of 11.16%. Subsequent culture was performed on the positive MRT samples. All results were negative, apart from a single sample, obtained from a serologically positive goat in Quito, that was positive for Brucella abortus strain 19 (B19). Several hypotheses are forwarded concerning this unexpected result. The most likely hypothesis is the possible accidental use of a needle, previously used for vaccination of cattle with the said vaccine, for the administration of drug treatment to the goat. This hypothesis underlines the necessity of biosecurity measures to prevent this type of accidents.

  19. 9 CFR 113.312 - Rabies Vaccine, Live Virus.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 9 Animals and Animal Products 1 2012-01-01 2012-01-01 false Rabies Vaccine, Live Virus. 113.312... Virus Vaccines § 113.312 Rabies Vaccine, Live Virus. Rabies Vaccine shall be prepared from virus-bearing..., safe and immunogenic shall be used for preparing the production seed virus for vaccine production....

  20. 9 CFR 113.312 - Rabies Vaccine, Live Virus.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 9 Animals and Animal Products 1 2013-01-01 2013-01-01 false Rabies Vaccine, Live Virus. 113.312... Virus Vaccines § 113.312 Rabies Vaccine, Live Virus. Rabies Vaccine shall be prepared from virus-bearing..., safe and immunogenic shall be used for preparing the production seed virus for vaccine production....

  1. 9 CFR 113.312 - Rabies Vaccine, Live Virus.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 9 Animals and Animal Products 1 2010-01-01 2010-01-01 false Rabies Vaccine, Live Virus. 113.312... Virus Vaccines § 113.312 Rabies Vaccine, Live Virus. Rabies Vaccine shall be prepared from virus-bearing..., safe and immunogenic shall be used for preparing the production seed virus for vaccine production....

  2. 9 CFR 113.312 - Rabies Vaccine, Live Virus.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 9 Animals and Animal Products 1 2014-01-01 2014-01-01 false Rabies Vaccine, Live Virus. 113.312... Virus Vaccines § 113.312 Rabies Vaccine, Live Virus. Rabies Vaccine shall be prepared from virus-bearing..., safe and immunogenic shall be used for preparing the production seed virus for vaccine production....

  3. 9 CFR 113.312 - Rabies Vaccine, Live Virus.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 9 Animals and Animal Products 1 2011-01-01 2011-01-01 false Rabies Vaccine, Live Virus. 113.312... Virus Vaccines § 113.312 Rabies Vaccine, Live Virus. Rabies Vaccine shall be prepared from virus-bearing..., safe and immunogenic shall be used for preparing the production seed virus for vaccine production....

  4. Influenza virus vaccine live intranasal--MedImmune vaccines: CAIV-T, influenza vaccine live intranasal.

    PubMed

    2003-01-01

    MedImmune Vaccines (formerly Aviron) has developed a cold-adapted live influenza virus vaccine [FluMist] that can be administered by nasal spray. FluMist is the first live virus influenza vaccine and also the first nasally administered vaccine to be marketed in the US. The vaccine will be formulated to contain live attenuated (att) influenza virus reassortants of the strains recommended by the US Public Health Service for each 'flu season. The vaccine is termed cold-adapted (ca) because the virus has been adapted to replicate efficiently at 25 degrees C in the nasal passages, which are below normal body temperature. The strains used in the seasonal vaccine will also be made temperature sensitive (ts) so that their replication is restricted at 37 degrees C (Type B strains) and 39 degrees C (Type A strains). The combined effect of the antigenic properties and the att, ca and ts phenotypes of the influenza strains contained in the vaccine enables the viruses to replicate in the nasopharynx to produce protective immunity. The original formulation of FluMist requires freezer storage throughout distribution. Because many international markets do not have distribution channels well suited to the sale of frozen vaccines, Wyeth and MedImmune are collaborating to develop a second generation, refrigerator-stable, liquid trivalent cold-adapted influenza vaccine (CAIV-T), which is in phase III trials. Initially, the frozen formulation will only be available in the US. For the 2003-2004 season, FluMist will contain A/New Caledonia/20/99 (H1N1), A/Panama/2007/99 (H3N2) (A/Moscow/10/99-like) and B/Hong Kong/330/2001. Aviron was acquired by MedImmune on 15 January 2002. Aviron is now a wholly-owned subsidiary of MedImmune and is called MedImmune Vaccines. Aviron acquired FluMist in March 1995 through a Co-operative Research and Development Agreement (CRADA) with the US NIAID, and a licensing agreement with the University of Michigan, Ann Arbor, USA. In June 2000, the CRADA was

  5. Brucella abortus as a potential vaccine candidate: induction of interleukin-12 secretion and enhanced B7.1 and B7.2 and intercellular adhesion molecule 1 surface expression in elutriated human monocytes stimulated by heat-inactivated B. abortus.

    PubMed Central

    Zaitseva, M; Golding, H; Manischewitz, J; Webb, D; Golding, B

    1996-01-01

    Development of a vaccine which is capable of generating a strong cellular immune response associated with gamma interferon (IFN-gamma) production and cytotoxic T-cell development requires that the immunogen be capable of inducing the secretion of interleukin-12 (IL-12), which is a pivotal factor for the differentiation of Th1 or Tc1 cells. We have previously shown that the heat-inactivated gram-negative bacterium Brucella abortus can induce IFN-gamma secretion by T cells. In the present study, we demonstrate that B. abortus and lipopolysaccharide (LPS) from B. abortus can induce IL-12 p40 mRNA expression and protein secretion by human elutriated monocytes (99% pure). p40 mRNA was detected within 4 h, and p40 protein could be measured at 24 h. This induction was abrogated by anti-CD14 monoclonal antibody, suggesting that monocytes recognize B. abortus via their receptor for LPS. The biological activity of IL-12 secreted by B. abortus-stimulated monocytes was demonstrated by its ability to upregulate IFN-gamma mRNA expression in T cells separated from monocytes and B. abortus by a transwell membrane. The B. abortus-induced IL-12 also enhanced NK cytolytic activity against K562 target cells. B. abortus was shown to rapidly increase the expression of the costimulatory molecules B7.1 and B7.2 and intercellular adhesion molecule 1 on human monocytes. Together, these data indicate that B. abortus can directly activate human monocytes and provide the cytokine milieu which would direct the immune response towards Th1-Tc1 differentiation. PMID:8757841

  6. Protective immunity elicited by a divalent DNA vaccine encoding both the L7/L12 and Omp16 genes of Brucella abortus in BALB/c mice.

    PubMed

    Luo, Deyan; Ni, Bing; Li, Peng; Shi, Wei; Zhang, Songle; Han, Yue; Mao, Liwei; He, Yangdong; Wu, Yuzhang; Wang, Xiliang

    2006-05-01

    This study was designed to evaluate the immunogenicity and the protective efficacy of a divalent fusion DNA vaccine encoding both the Brucella abortus L7/L12 protein (ribosomal protein) and Omp16 protein (outer membrane lipoprotein), designated pcDNA3.1-L7/L12-Omp16. Intramuscular injection of this divalent DNA vaccine into BALB/c mice elicited markedly both humoral and cellular immune responses. The specific antibodies exhibited a dominance of immunoglobulin G2a (IgG2a) over IgG1. In addition, the dual-gene DNA vaccine elicited a strong T-cell proliferative response and induced a large amount of gamma interferon-producing T cells upon restimulation in vitro with recombinant fusion protein L7/L12-Omp16, suggesting the induction of a typical T-helper-1-dominated immune response in vivo. This divalent DNA vaccine could also induce a significant level of protection against challenge with the virulent strain B. abortus 544 in BALB/c mice. Furthermore, the protection level induced by the divalent DNA vaccine was significantly higher than that induced by the univalent DNA vaccines pcDNA3.1-L7/L12 or pcDNA3.1-Omp16. Taken together, the results of this study verify for the first time that the Omp16 gene can be a candidate target for a DNA vaccine against brucellosis. Additionally, a divalent genetic vaccine based on the L7/L12 and Omp16 genes can elicit a stronger cellular immune response and better immunoprotection than the relevant univalent vaccines can.

  7. Mycoplasma gallisepticum: Control by live attenuated vaccines

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Commercially available attenuated strains of Mycoplasma gallisepticum (MG) are commonly used within the layer industry to control MG-induced mycoplasmosis. Among these are two live MG vaccines derived from the moderately pathogenic MG “chick F” strain. In the present study, the commercially availa...

  8. First evaluation of an influenza viral vector based Brucella abortus vaccine in sheep and goats: Assessment of safety, immunogenicity and protective efficacy against Brucella melitensis infection.

    PubMed

    Tabynov, Kaissar; Yespembetov, Bolat; Matikhan, Nurali; Ryskeldinova, Sholpan; Zinina, Nadezhda; Kydyrbayev, Zhailaubay; Assanzhanova, Nurika; Tabynov, Kairat; Renukaradhya, Gourapura J; Mukhitdinova, Gulnara; Sansyzbay, Abylai

    2016-12-25

    Previously we developed and evaluated a candidate influenza viral vector based Brucella abortus vaccine (Flu-BA) administered with a potent adjuvant Montanide Gel01 in cattle, which was found safe and highly effective. This study was aimed to establish a proof-of-concept of the efficacy of Flu-BA vaccine formulation in sheep and goats. We vaccinated sheep and goats with Flu-BA vaccine and as a positive control vaccinated a group of animals with a commercial B. melitensis Rev.1 vaccine. Clinically, both Flu-BA and Rev.1 vaccines were found safe. Serological analysis showed the animals received Flu-BA vaccine did not induce antibody response against Brucella Omp16 and L7/L12 proteins during the period of our study (56days post-initial vaccination, PIV). But observed significant antigen-specific T cell response indicated by increased lymphocyte stimulation index and enhanced secretion of IFN-γ at day 56 PIV in Flu-BA group. The Flu-BA vaccinated animals completely protected 57.1% of sheep and 42.9% of goats against B. melitensis 16M challenge. The severity of brucellosis in terms of infection index and colonization of Brucella in tissues was significantly lower in the Flu-BA group compared to negative control animals group. Nevertheless, positive control commercial Rev.1 vaccine provided strong antigen-specific T cell immunity and protection against B. melitensis 16M infection. We conclude that the Flu-BA vaccine induces a significant antigen-specific T-cell response and provides complete protection in approximately 50% of sheep and goats against B. melitensis 16M infection. Further investigations are needed to improve the efficacy of Flu-BA and explore its practical application in small ruminants.

  9. Evaluation of immunogenicity and protective efficacy of a plasmid DNA vaccine encoding ribosomal protein L9 of Brucella abortus in BALB/c mice.

    PubMed

    Jain, Shikha; Afley, Prachiti; Dohre, Sudhir K; Saxena, Nandita; Kumar, Subodh

    2014-07-31

    Brucellosis is a worldwide zoonotic disease. No Brucella vaccine is available for use in humans and existing animal vaccines have limitations. We have previously described the ribosomal protein L9 to have the vaccine potential. In this study, L9 based DNA vaccine (pVaxL9) was generated and evaluated in mouse model. Intramuscular immunisation of pVaxL9 was able to elicit the anti-L9 IgG antibody response of both IgG1 and IgG2a isotypes when compared with PBS and pVax immunised control animals. Heightened antibody response was observed in mice groups immunised with pVaxL9 priming and recombinant L9 boosting (PB) and where pDNA immunisation was carried out by in vivo electroporation (EP). The vaccine groups proliferated splenocytes and released Th1 type cytokines e.g. IFN-γ, TNF-α, IL-2. Further, flow cytometric analysis revealed that IFN-γ was released by both by CD4+ and CD8+ T cells particularly in PB and EP groups when compared with mice immunised with empty control vector. The L9 based pDNA vaccine was able to confer significant protection in mice against challenge with virulent B. abortus with PB and EP groups offering better protection. Taken together, it can be concluded that L9 based DNA vaccine is immunogenic and confer protection in mouse model.

  10. Development of Streptococcus pneumoniae Vaccines Using Live Vectors

    PubMed Central

    Wang, Shifeng; Curtiss, Roy

    2014-01-01

    Streptococcus pneumoniae still causes severe morbidity and mortality worldwide, especially in young children and the elderly. Much effort has been dedicated to developing protein-based universal vaccines to conquer the current shortcomings of capsular vaccines and capsular conjugate vaccines, such as serotype replacement, limited coverage and high costs. A recombinant live vector vaccine delivering protective antigens is a promising way to achieve this goal. In this review, we discuss the researches using live recombinant vaccines, mainly live attenuated Salmonella and lactic acid bacteria, to deliver pneumococcal antigens. We also discuss both the limitations and the future of these vaccines. PMID:25309747

  11. Excretion of Brucella abortus vaccine B19 strain during a reproductive cycle in dairy cows

    PubMed Central

    Pacheco, W. A.; Genovez, M. E.; Pozzi, C. R.; Silva, L. M. P.; Azevedo, S. S.; Did, C. C.; Piatti, R. M.; Pinheiro, E. S.; Castro, V.; Miyashiro, S.; Gambarini, M. L.

    2012-01-01

    This paper aimed to determine the excretion period of B19 vaccine strain during a complete reproductive cycle (from estrus synchronization, artificial insemination, pregnancy and until 30 days after parturition) of dairy cows from 3 to 9 years old that were previously vaccinated from 3 to 8 months. Three groups were monitored with monthly milk and urine collection during 12 months: G1 with seven cows from 3 to 4 years old; G2 with three cows from 5 to 6 years old; and G3 with four cows from 7 to 9 years old. Urine and milk samples were submitted to bacteriological culture and urine and PCR reactions for detection of Brucella spp. and PCR-multiplex for B19 strain identification. Ring test (RT) was also performed in the milk samples, and serum samples were tested by buffered acidified plate antigen test (BAPA). All animals were serologically negative at BAPA and Brucella spp. was not isolated from both urine and milk samples. RT revealed 13/210 (6.2%) positive milk samples. PCR reactions detected DNA of Brucella spp. in 86/420 (20.5%) samples. In urine it was found a significantly higher frequency (35.2%; 74/210) than in milk (5.7%; 12/210), more frequently from the estrus to 150 days of pregnancy and after parturition (6.7%; 10/150), and from 150 days of pregnancy to parturition (3.4%; 2/60), and they were all identified as B19 strain. In three groups, intermittent excretion of B19 strain was detected mainly in urine samples, which confirmed its multiplication and persistence in cows for until 9 years. PMID:24031869

  12. Live bacterial vaccine vectors: An overview

    PubMed Central

    da Silva, Adilson José; Zangirolami, Teresa Cristina; Novo-Mansur, Maria Teresa Marques; Giordano, Roberto de Campos; Martins, Elizabeth Angélica Leme

    2014-01-01

    Genetically attenuated microorganisms, pathogens, and some commensal bacteria can be engineered to deliver recombinant heterologous antigens to stimulate the host immune system, while still offering good levels of safety. A key feature of these live vectors is their capacity to stimulate mucosal as well as humoral and/or cellular systemic immunity. This enables the use of different forms of vaccination to prevent pathogen colonization of mucosal tissues, the front door for many infectious agents. Furthermore, delivery of DNA vaccines and immune system stimulatory molecules, such as cytokines, can be achieved using these special carriers, whose adjuvant properties and, sometimes, invasive capacities enhance the immune response. More recently, the unique features and versatility of these vectors have also been exploited to develop anti-cancer vaccines, where tumor-associated antigens, cytokines, and DNA or RNA molecules are delivered. Different strategies and genetic tools are constantly being developed, increasing the antigenic potential of agents delivered by these systems, opening fresh perspectives for the deployment of vehicles for new purposes. Here we summarize the main characteristics of the different types of live bacterial vectors and discuss new applications of these delivery systems in the field of vaccinology. PMID:25763014

  13. Protective effect of a DNA vaccine containing an open reading frame with homology to an ABC-type transporter present in the genomic island 3 of Brucella abortus in BALB/c mice.

    PubMed

    Riquelme-Neira, Roberto; Retamal-Díaz, Angello; Acuña, Francisca; Riquelme, Pablo; Rivera, Alejandra; Sáez, Darwin; Oñate, Angel

    2013-08-12

    The immunogenicity of a DNA vaccine containing an open reading frame (ORF) of genomic island 3 (GI-3), specific for Brucella abortus and Brucella melitensis, has been examined. Intramuscular injection of plasmid DNA carrying the open reading frame with homology to an ABC-type transporter (pV278a) into BALB/c mice elicited both humoral and cellular immune responses. Mice injected with pV278a had a dominant immunoglobulin G2a (IgG2a) response. This DNA vaccine elicited a T-cell-proliferative response and induced significant levels of interferon gamma (INF-γ) upon restimulation with recombinant 278a protein. Upon stimulation with an appropriate recombinant protein or crude Brucella protein, the vaccine did not induce IL-4, suggesting a typical T-helper (TH1) response. Furthermore, the vaccine induced protection in BALB/c mice when challenged with the virulent strain Brucella abortus 2308. Taken together, these data suggest that DNA vaccination offers an improved delivery of the homologous of an ABC-type transporter antigen, and provides the first evidence of a protective effect of this antigen in the construction of vaccines against B. abortus.

  14. Vaccination with recombinant flagellar proteins FlgJ and FliN induce protection against Brucella abortus 544 infection in BALB/c mice.

    PubMed

    Li, Xianbo; Xu, Jie; Xie, Yongfei; Qiu, Yefeng; Fu, Simei; Yuan, Xitong; Ke, Yuehua; Yu, Shuang; Du, Xinying; Cui, Mingquan; Chen, Yanfen; Wang, Tongkun; Wang, Zhoujia; Yu, Yaqing; Huang, Kehe; Huang, Liuyu; Peng, Guangneng; Chen, Zeliang; Wang, Yufei

    2012-12-28

    Brucella has been considered as a non-motile, facultative intracellular pathogenic bacterium. However, the genome sequences of different Brucella species reveal the presence of the flagellar genes needed for the construction of a functional flagellum. Due to its roles in the interaction between pathogen and host, we hypothesized that some of the flagellar proteins might induce protective immune responses and these proteins will be good subunit vaccine candidates. This study was conducted to screening of protective antigens among these flagellar proteins. Firstly, according to the putative functional roles, a total of 30 flagellar genes of Brucella abortus were selected for in vitro expression. 15 of these flagellar genes were successfully expressed as his-tagged recombinant proteins in Escherichia coli ER2566. Then, these proteins were purified and used to analyze their T cell immunity induction activity by an in vitro gamma interferon (IFN-γ) assay. Five of the flagellar proteins could stimulate significantly higher levels of IFN-γ secretion in splenocytes from S19 immunized mice, indicating their T cell induction activity. Finally, immunogenicity and protection activity of these 5 flagellar proteins were evaluated in BALB/c mice. Results showed that immunization with FlgJ (BAB1_0260) or FliN (BAB2_0122) plus adjuvant could provide protection against B. abortus 544 infection. Furthermore, mice immunized with FlgJ and FliN developed a vigorous immunoglobulin G response, and in vitro stimulation of their splenocytes with immunizing proteins induced the secretion of IFN-γ. Altogether, these data suggest that flagellar proteins FlgJ and FliN are protective antigens that could produce humoral and cell-mediated responses in mice and candidates for use in future studies of vaccination against brucellosis.

  15. Research progress in live attenuated Brucella vaccine development.

    PubMed

    Wang, Zhen; Wu, Qingmin

    2013-01-01

    Brucella spp. are facultative intracellular bacteria that cause brucellosis, which is a globally occurring zoonotic disease that is characterized by abortion in domestic animals and undulant fever, arthritis, endocarditis, and meningitis in humans. There are currently no licensed vaccines against brucellosis for human use, and only a few licensed live Brucella vaccines are available for use in animals. However, the available animal vaccines may cause abortion and are associated with lower protection rates in animals and higher virulence in humans. Much research has been performed recently to develop novel Brucella vaccines for the prevention and control of animal brucellosis. This article discusses the approaches and strategies for novel live attenuated vaccine development.

  16. Identification of an IS711 Element Interrupting the wboA Gene of Brucella abortus Vaccine Strain RB51 and a PCR Assay To Distinguish Strain RB51 from Other Brucella Species and Strains

    PubMed Central

    Vemulapalli, Ramesh; McQuiston, John R.; Schurig, Gerhardt G.; Sriranganathan, Nammalwar; Halling, Shirley M.; Boyle, Stephen M.

    1999-01-01

    Brucella abortus vaccine strain RB51 is a natural stable attenuated rough mutant derived from the virulent strain 2308. The genetic mutations that are responsible for the roughness and the attenuation of strain RB51 have not been identified until now. Also, except for an assay based on pulsed-field gel electrophoresis, no other simple method to differentiate strain RB51 from its parent strain 2308 is available. In the present study, we demonstrate that the wboA gene encoding a glycosyltransferase, an enzyme essential for the synthesis of O antigen, is disrupted by an IS711 element in B. abortus vaccine strain RB51. Exploiting this feature, we developed a PCR assay that distinguishes strain RB51 from all other Brucella species and strains tested. PMID:10473532

  17. Recent Developments in Livestock and Wildlife Brucellosis Vaccination

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Live attenuated brucellosis vaccines have been available for protecting domestic livestock against B. melitensis or B. abortus for more than 60 years. Current vaccines are effective in preventing abortion and transmission of brucellosis, but poor at preventing infection or seroconversion. In addit...

  18. Live virus vaccination near a pregnancy: flawed policies, tragic results.

    PubMed

    Yazbak, F Edward; Yazbak, Kathleen

    2002-09-01

    Vaccination of women with live virus vaccines around conception has always been contraindicated by the Center for Disease Control and Prevention (CDC) and the vaccine manufacturer because of potential risks to the fetus. Nevertheless this dangerous practice occurs and is associated with maternal health problems and a very high incidence of early-onset autism in the children. Postpartum vaccination with live virus vaccines has been recommended by the CDC, and described as 'convenient' by the vaccine manufacturer. This 'routine practice' may lead to health and is also associated with many health and obstetrical problems in the recipient, and is frequently associated with autism in both current and future children. Re-vaccination often fails to produce immunity, the very reason for which it was recommended.

  19. Evaluation of immunogenicity and protective efficacy of a liposome containing Brucella abortus S19 outer membrane protein in BALB/c mice

    PubMed Central

    Mukherjee, F.; Prasad, A.; Bahekar, V. S.; Rana, S. K.; Rajendra, L.; Sharma, G. K.; Srinivasan, V. A.

    2016-01-01

    The use of liposome as an adjuvant and a vaccine carrier has been cited previously in the literature. It has also been shown to be effective in enhancing the immunogenicity of vaccine candidates. BALB/c mice immunized subcutaneously with outer membrane protein (OMP) of Brucella abortus S19 vaccine strain entrapped in a commercial cationic liposome (S19-OMP-liposome) for vaccine delivery, showed enhanced protection (P<0.05) compared to groups of mice inoculated with S19 OMP alone, S19 live B. abortus vaccine and liposome alone, when challenged intra-peritoneally with virulent B. abortus strain 544 at 30 days post-immunization (DPI). The S19-OMP-liposome preparation was found to be safer compared to the live B. abortus S19 vaccine at 15 days post challenge (DPC), as evidenced by the significant difference in spleen weight between S19-OMP-liposome, S19 OMP and S19 live as well as the liposome control groups (P<0.01). Antibody isotype response profiles of the experimental groups indicated that the immune response was Th1 cell mediated. The protective advantage conferred to mice immunized with S19-OMP entrapped in liposome over those immunized with the live B. abortus S19 version, could probably be related to the significantly different response of IgG2b at 30 DPI (P<0.01), IgG2a (P<0.01), IgG2b (P<0.01) and IgG3 (P<0.05) at the DPC stages, respectively. PMID:27656221

  20. The delicate balance in genetically engineering live vaccines

    PubMed Central

    Galen, James E.; Curtiss, Roy

    2014-01-01

    Contemporary vaccine development relies less on empirical methods of vaccine construction, and now employs a powerful array of precise engineering strategies to construct immunogenic live vaccines. In this review, we will survey various engineering techniques used to create attenuated vaccines, with an emphasis on recent advances and insights. We will further explore the adaptation of attenuated strains to create multivalent vaccine platforms for immunization against multiple unrelated pathogens. These carrier vaccines are engineered to deliver sufficient levels of protective antigens to appropriate lymphoid inductive sites to elicit both carrier-specific and foreign antigen-specific immunity. Although many of these technologies were originally developed for use in Salmonella vaccines, application of the essential logic of these approaches will be extended to development of other enteric vaccines where possible. A central theme driving our discussion will stress that the ultimate success of an engineered vaccine rests on achieving the proper balance between attenuation and immunogenicity. Achieving this balance will avoid over-activation of inflammatory responses, which results in unacceptable reactogenicity, but will retain sufficient metabolic fitness to enable the live vaccine to reach deep tissue inductive sites and trigger protective immunity. The breadth of examples presented herein will clearly demonstrate that genetic engineering offers the potential for rapidly propelling vaccine development forward into novel applications and therapies which will significantly expand the role of vaccines in public health. PMID:24370705

  1. The delicate balance in genetically engineering live vaccines.

    PubMed

    Galen, James E; Curtiss, Roy

    2014-07-31

    Contemporary vaccine development relies less on empirical methods of vaccine construction, and now employs a powerful array of precise engineering strategies to construct immunogenic live vaccines. In this review, we will survey various engineering techniques used to create attenuated vaccines, with an emphasis on recent advances and insights. We will further explore the adaptation of attenuated strains to create multivalent vaccine platforms for immunization against multiple unrelated pathogens. These carrier vaccines are engineered to deliver sufficient levels of protective antigens to appropriate lymphoid inductive sites to elicit both carrier-specific and foreign antigen-specific immunity. Although many of these technologies were originally developed for use in Salmonella vaccines, application of the essential logic of these approaches will be extended to development of other enteric vaccines where possible. A central theme driving our discussion will stress that the ultimate success of an engineered vaccine rests on achieving the proper balance between attenuation and immunogenicity. Achieving this balance will avoid over-activation of inflammatory responses, which results in unacceptable reactogenicity, but will retain sufficient metabolic fitness to enable the live vaccine to reach deep tissue inductive sites and trigger protective immunity. The breadth of examples presented herein will clearly demonstrate that genetic engineering offers the potential for rapidly propelling vaccine development forward into novel applications and therapies which will significantly expand the role of vaccines in public health.

  2. Novel vaccine against Venezuelan equine encephalitis combines advantages of DNA immunization and a live attenuated vaccine.

    PubMed

    Tretyakova, Irina; Lukashevich, Igor S; Glass, Pamela; Wang, Eryu; Weaver, Scott; Pushko, Peter

    2013-02-04

    DNA vaccines combine remarkable genetic and chemical stability with proven safety and efficacy in animal models, while remaining less immunogenic in humans. In contrast, live-attenuated vaccines have the advantage of inducing rapid, robust, long-term immunity after a single-dose vaccination. Here we describe novel iDNA vaccine technology that is based on an infectious DNA platform and combines advantages of DNA and live attenuated vaccines. We applied this technology for vaccination against infection with Venezuelan equine encephalitis virus (VEEV), an alphavirus from the Togaviridae family. The iDNA vaccine is based on transcription of the full-length genomic RNA of the TC-83 live-attenuated virus from plasmid DNA in vivo. The in vivo-generated viral RNA initiates limited replication of the vaccine virus, which in turn leads to efficient immunization. This technology allows the plasmid DNA to launch a live-attenuated vaccine in vitro or in vivo. Less than 10 ng of pTC83 iDNA encoding the full-length genomic RNA of the TC-83 vaccine strain initiated replication of the vaccine virus in vitro. In order to evaluate this approach in vivo, BALB/c mice were vaccinated with a single dose of pTC83 iDNA. After vaccination, all mice seroconverted with no adverse reactions. Four weeks after immunization, animals were challenged with the lethal epidemic strain of VEEV. All iDNA-vaccinated mice were protected from fatal disease, while all unvaccinated controls succumbed to infection and died. To our knowledge, this is the first example of launching a clinical live-attenuated vaccine from recombinant plasmid DNA in vivo.

  3. Immune responses and safety after dart or booster vaccination of bison with Brucella abortus strain RB51

    Technology Transfer Automated Retrieval System (TEKTRAN)

    One alternative in the Bison remote vaccination environmental impact statement (EIS) for Yellowstone National Park includes inoculation of both calves and yearlings. Although RB51 vaccination of bison does protect against experimental challenge, it was unknown whether booster vaccination might enhan...

  4. Potency control of modified live viral vaccines for veterinary use.

    PubMed

    Terpstra, C; Kroese, A H

    1996-01-01

    This paper reviews various aspects of efficacy, and methods for assaying the potency of modified live viral vaccines. The pros and cons of parametric versus non-parametric methods for analysis of potency assays are discussed and critical levels of protection, as determined by the target(s) of vaccination, are exemplified. Recommendations are presented for designing potency assays on master virus seeds and vaccine batches.

  5. Potency control of modified live viral vaccines for veterinary use.

    PubMed

    Terpstra, C; Kroese, A H

    1996-04-01

    This paper reviews various aspects of efficacy, and methods for assaying the potency of modified live viral vaccines. The pros and cons of parametric versus non-parametric methods for analysis of potency assays are discussed and critical levels of protection, as determined by the target(s) of vaccination, are exemplified. Recommendations are presented for designing potency assays on master virus seeds and vaccine batches.

  6. Live attenuated hepatitis A vaccines developed in China.

    PubMed

    Xu, Zhi-Yi; Wang, Xuan-Yi

    2014-01-01

    Two live, attenuated hepatitis A vaccines, H 2 and LA-1 virus strains, were developed through serial passages of the viruses in cell cultures at 32 °C and 35 °C respectively. Both vaccines were safe and immunogenic, providing protection against clinical hepatitis A in 95% of the vaccinees, with a single dose by subcutaneous injection. The vaccine recipients were not protected from asymptomatic, subclinical hepatitis A virus (HAV) infection, which induced a similar antibody response as for unvaccinated subjects. A second dose caused anamnestic response and can be used for boosting. Oral immunization of human with H 2 vaccine or of marmoset with LA-1 vaccine failed, and no evidence was found for person-to-person transmission of the H 2 strain or for marmoset-to-marmoset transmission of LA-1 strain, by close contact. H 2 strain was genetically stable when passaged in marmosets, humans or cell cultures at 37 °C; 3 consecutive passages of the virus in marmosets did not cause virulence mutation. The live vaccines offer the benefits of low cost, single dose injection, long- term protection, and increased duration of immunity through subclinical infection. Improved sanitation and administration of 150 million doses of the live vaccines to children had led to a 90% reduction in the annual national incidence rate of hepatitis A in China during the 16-year period, from 1991 to 2006. Hepatitis A immunization with both live and inactivated HA vaccines was implemented in the national routine childhood immunization program in 2008 and around 92% of the 16 million annual births received the affordable live, attenuated vaccines at 18 months of age. Near elimination of the disease was achieved in China for 14 years following introduction of the H 2 live vaccine into the Expanded Immunization Program (EPI) in 1992.

  7. Characterization and protective property of Brucella abortus cydC and looP mutants.

    PubMed

    Truong, Quang Lam; Cho, Youngjae; Barate, Abhijit Kashinath; Kim, Suk; Hahn, Tae-Wook

    2014-11-01

    Brucella abortus readily multiplies in professional or nonprofessional phagocytes in vitro and is highly virulent in mice. Isogenic mutants of B. abortus biovar 1 strain IVKB9007 lacking the ATP/GDP-binding protein motif A (P-loop) (named looP; designated here the IVKB9007 looP::Tn5 mutant) and the ATP-binding/permease protein (cydC; designated here the IVKB9007 cydC::Tn5 mutant) were identified and characterized by transposon mutagenesis using the mini-Tn5Km2 transposon. Both mutants were found to be virtually incapable of intracellular replication in both murine macrophages (RAW264.7) and the HeLa cell line, and their virulence was significantly impaired in BALB/c mice. Respective complementation of the IVKB9007 looP::Tn5 and IVKB9007 cydC::Tn5 mutants restored their ability to survive in vitro and in vivo to a level comparable with that of the wild type. These findings indicate that the cydC and looP genes play important roles in the virulence of B. abortus. In addition, intraperitoneal immunization of mice with a dose of the live IVKB9007 looP::Tn5 and IVKB9007 cydC::Tn5 mutants provided a high degree of protection against challenge with pathogenic B. abortus strain 544. Both mutants should be evaluated further as a live attenuated vaccine against bovine brucellosis for their ability to stimulate a protective immune response.

  8. Influenza vaccination with live-attenuated and inactivated virus-vaccines during an outbreak of disease.

    PubMed Central

    Rocchi, G.; Ragona, G.; Piga, C.; Pelosio, A.; Volpi, A.; Vella, S.; Legniti, N.; de Felici, A.

    1979-01-01

    Immunization procedures with live attenuated and inactivated vaccines were carried out on a group of young recruits at the beginning of an outbreak of infection due to an A/Victoria/3/75-related virus strain, which occurred in February 1977 in a military camp. A retrospective investigation on protection from clinical influenza was then performed in order to investigate whether immunization with live virus vaccines, administered at the beginning of an epidemic, could provide early protection from the disease. In the course of the two weeks following vaccination, laboratory-confirmed clinical influenza cases occurred in 4 subjects among the 110 volunteers of the control group which received placebo, and in 8, 7 and 4 subjects respectively of the 3 groups of about 125 individuals, each of which received one of the following vaccine preparations: (a), live attenuated A/Victoria/3/75 influenza virus oral vaccine, grown on chick embryo kidney culture; (b), live attenuated nasal vaccine, a recombinant of A/Puerto Rico/8/34 with A/Victoria/3/75 virus; and (c), inactivated A/Victoria/3/75 virus intramuscular vaccine. These data do not support the hypothesis that, during an epidemic of infection, early protection from clinical influenza can be achieved through immunization with live attenuated or inactivated influenza virus vaccines, in spite of the high immunizing capability of the vaccine preparations. PMID:512351

  9. Do vaccines save lives? Yes they do!

    PubMed

    Lernout, Tinne; Theeten, Heidi; Leuridan, Elke; Van Damme, Pierre

    2014-01-01

    Since their introduction and widespread use, vaccines have been very successful in reducing morbidity and mortality of the diseases they target, at an individual level and through herd immunity. The impact on the mortality has been rapid and easy to measure for some diseases, such as diphtheria, pertussis and measles. For other diseases, including hepatitis B and human papillomavirus infections, deaths averted occur many years after vaccination, and it takes years until the full potential of the vaccine can be established. Finally, in middle and high income countries, the impact of vaccination against some diseases, like invasive pneumococcal disease and rotavirus gastro-enteritis, is measured by decrease in incidence of the disease and reduction in hospitalization rather than impact on mortality. But in the countries with the highest incidence of these diseases, mortality remains high due to low availability of these vaccines, and millions of deaths could be averted by optimal use of vaccines in these regions. Major challenges for vaccination programmes are to maintain and strengthen trust in the benefits of vaccination and adapt immunization schedules according to the changing epidemiological landscape.

  10. A novel live-attenuated vaccine candidate for mayaro Fever.

    PubMed

    Weise, William J; Hermance, Meghan E; Forrester, Naomi; Adams, A Paige; Langsjoen, Rose; Gorchakov, Rodion; Wang, Eryu; Alcorn, Maria D H; Tsetsarkin, Konstantin; Weaver, Scott C

    2014-08-01

    Mayaro virus (MAYV) is an emerging, mosquito-borne alphavirus that causes a dengue-like illness in many regions of South America, and which has the potential to urbanize. Because no specific treatment or vaccine is available for MAYV infection, we capitalized on an IRES-based approach to develop a live-attenuated MAYV vaccine candidate. Testing in infant, immunocompetent as well as interferon receptor-deficient mice demonstrated a high degree of attenuation, strong induction of neutralizing antibodies, and efficacy against lethal challenge. This vaccine strain was also unable to infect mosquito cells, a major safety feature for a live vaccine derived from a mosquito-borne virus. Further preclinical development of this vaccine candidate is warranted to protect against this important emerging disease.

  11. A Novel Live-Attenuated Vaccine Candidate for Mayaro Fever

    PubMed Central

    Weise, William J.; Hermance, Meghan E.; Forrester, Naomi; Adams, A. Paige; Langsjoen, Rose; Gorchakov, Rodion; Wang, Eryu; Alcorn, Maria D. H.; Tsetsarkin, Konstantin; Weaver, Scott C.

    2014-01-01

    Mayaro virus (MAYV) is an emerging, mosquito-borne alphavirus that causes a dengue-like illness in many regions of South America, and which has the potential to urbanize. Because no specific treatment or vaccine is available for MAYV infection, we capitalized on an IRES-based approach to develop a live-attenuated MAYV vaccine candidate. Testing in infant, immunocompetent as well as interferon receptor-deficient mice demonstrated a high degree of attenuation, strong induction of neutralizing antibodies, and efficacy against lethal challenge. This vaccine strain was also unable to infect mosquito cells, a major safety feature for a live vaccine derived from a mosquito-borne virus. Further preclinical development of this vaccine candidate is warranted to protect against this important emerging disease. PMID:25101995

  12. Promises and pitfalls of live attenuated pneumococcal vaccines.

    PubMed

    Rosch, Jason W

    2014-01-01

    The pneumococcus is a remarkably adaptable pathogen whose disease manifestations range from mucosal surface infections such as acute otitis media and pneumonia to invasive infections such as sepsis and meningitis. Currently approved vaccines target the polysaccharide capsule, of which there are over 90 distinct serotypes, leading to rapid serotype replacement in vaccinated populations. Substantial progress has been made in the development of a universal pneumococcal vaccine, with efforts focused on broadly conserved and protective protein antigens. An area attracting considerable attention is the potential application of live attenuated vaccines to confer serotype-independent protection against mucosal and systemic infection. On the basis of recent work to understand the mucosal and systemic responses to nasal administration of pneumococci and to develop novel attenuation strategies, the prospect of a practical and protective live vaccine remains promising.

  13. Update: potential exposures to attenuated vaccine strain Brucella abortus RB51 during a laboratory proficiency test--United States and Canada, 2007.

    PubMed

    2008-01-18

    In November 2007, New York State Department of Health (NYSDOH) officials notified CDC of potential exposures to attenuated vaccine strain Brucella abortus RB51 (RB51) in multiple clinical laboratories that participated in a Laboratory Preparedness Survey (LPS) proficiency test. NYSDOH conducted a survey of participating laboratories and identified 17 laboratories that reported handling the RB51 sample in a manner placing lab workers at potential risk for exposure. Subsequently, CDC recommended that public health officials conduct a review of biosafety practices at all LPS-participating laboratories to identify any additional RB51 exposures. This report summarizes the results of investigations in 36 states, two cities, one county, and the District of Columbia. As of January 14, 2008, follow-up by public health officials with LPS-participating laboratories throughout the United States identified a total of 916 laboratory workers in 254 laboratories with potential RB51 exposure. The results highlight the need for routine adherence to recommended biosafety practices when working with infectious organisms, particularly during widespread infectious-disease events, including bioterrorism attacks.

  14. Oral immunization of mice with recombinant Lactococcus lactis expressing Cu,Zn superoxide dismutase of Brucella abortus triggers protective immunity.

    PubMed

    Sáez, Darwin; Fernández, Pablo; Rivera, Alejandra; Andrews, Edilia; Oñate, Angel

    2012-02-08

    Brucella infections mainly occur through mucosal surfaces. Thus, the development of mucosal administered vaccines could be instrumental for the control of brucellosis. Here, we evaluated the usefulness of recombinant Lactococcus lactis secreting Brucella abortus Cu-Zn superoxide dismutase (SOD) as oral antigen delivery system, when administered alone or in combination with L. lactis expressing IL-12. To this end, mice were vaccinated by oral route with L. lactis NZ9000 transformed with pSEC derivatives encoding for SOD (pSEC:SOD) and IL-12 (pSEC:scIL-12). In animals receiving L. lactis pSEC:SOD alone, anti-SOD-specific IgM antibodies were detected in sera at day 28 post-vaccination, together with an IgG2a dominated IgG response. SOD-specific sIgA was also detected in nasal and bronchoalveolar lavages. In addition, T-cell-proliferative responses upon re-stimulation with either recombinant SOD or crude Brucella protein extracts were observed up to 6 months after the last boost, suggesting the induction of long term memory. Vaccinated animals were also protected against challenge with the virulent B. abortus 2308 strain. Responses were mildly improved when L. lactis pSEC:SOD was co-administered with L. lactis pSEC:scIL-12. These results indicated that vaccines based on lactococci-derived live carriers are promising interventions against B. abortus infections.

  15. Immunization of newborn children with living oral trivalent poliovirus vaccine.

    PubMed

    CAMPILLO-SAINZ, C; ORNELAS HERNANDEZ, A; DE MUCHA MACIAS, J; NAVA, S E

    1962-09-01

    Campillo-Sainz, C. (Instituto Nacional de Virología de la S.S.A., México, D.F.), A. Ornelas Hernandez, J. de Mucha Macías, and S. E. Nava. Immunization of newborn children with living oral trivalent poliovirus vaccine. J. Bacteriol. 84:446-450. 1962.-The serological response to one dose of living oral trivalent polio-virus vaccine was compared in two groups of children, 49 vaccinated at birth and 44 vaccinated at the age of 4 months. Of those vaccinated at birth, 44 (90%) responded to the vaccine strains of type 1 and type 3 and 30 (61%) to the type 2 strain. Of those vaccinated at 4 months of age; 64% responded to type 1, 52% to type 2, and 82% to type 3. The difference between the responses of the two groups, which for type 1 is significant, may result from the interference of other enteric viruses in the 4-month-old children. A second dose of vaccine, administered to the children vaccinated at birth when they reached the age of 4 months, increased the over-all immunological response to 100% for types 1 and 3 and 96% for type 2, and showed that no immunological tolerance had been developed. The vaccine produced no undesirable effects in any of the children, and no paralytic poliomyelitis occurred among them. The observation of other investigators, that a high titer of maternal antibody inhibits immunological response to vaccination, was confirmed, but breast feeding apparently had no unfavorable effect on response.

  16. Dominance of Human Innate Immune Responses in Primary Francisella tularensis Live Vaccine Strain Vaccination

    DTIC Science & Technology

    2006-03-31

    Diseases, Bacteriology Division, 425 Porter St, Frederick , MD 21702-5011. Dr Brittingham is the recipient of the National Research Council Fellowship...tularemia vaccine strain) infection by the sera of human recipients of the live tula- remia vaccine. Am J Med Sci 1994;308:83-7. 10. Herzberg VL

  17. 9 CFR 113.300 - General requirements for live virus vaccines.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... vaccines. 113.300 Section 113.300 Animals and Animal Products ANIMAL AND PLANT HEALTH INSPECTION SERVICE... REQUIREMENTS Live Virus Vaccines § 113.300 General requirements for live virus vaccines. When prescribed in an applicable Standard Requirement or in the filed Outline of Production, a live virus vaccine shall meet...

  18. 9 CFR 113.300 - General requirements for live virus vaccines.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... vaccines. 113.300 Section 113.300 Animals and Animal Products ANIMAL AND PLANT HEALTH INSPECTION SERVICE... REQUIREMENTS Live Virus Vaccines § 113.300 General requirements for live virus vaccines. When prescribed in an applicable Standard Requirement or in the filed Outline of Production, a live virus vaccine shall meet...

  19. 9 CFR 113.71 - Chlamydia Psittaci Vaccine (Feline Pneumonitis), Live Chlamydia.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 9 Animals and Animal Products 1 2013-01-01 2013-01-01 false Chlamydia Psittaci Vaccine (Feline... VECTORS STANDARD REQUIREMENTS Live Bacterial Vaccines § 113.71 Chlamydia Psittaci Vaccine (Feline Pneumonitis), Live Chlamydia. Chlamydia Psittaci Vaccine (Feline Pneumonitis), Live Chlamydia, shall...

  20. 9 CFR 113.71 - Chlamydia Psittaci Vaccine (Feline Pneumonitis), Live Chlamydia.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 9 Animals and Animal Products 1 2011-01-01 2011-01-01 false Chlamydia Psittaci Vaccine (Feline... VECTORS STANDARD REQUIREMENTS Live Bacterial Vaccines § 113.71 Chlamydia Psittaci Vaccine (Feline Pneumonitis), Live Chlamydia. Chlamydia Psittaci Vaccine (Feline Pneumonitis), Live Chlamydia, shall...

  1. 9 CFR 113.300 - General requirements for live virus vaccines.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... vaccines. 113.300 Section 113.300 Animals and Animal Products ANIMAL AND PLANT HEALTH INSPECTION SERVICE... REQUIREMENTS Live Virus Vaccines § 113.300 General requirements for live virus vaccines. When prescribed in an applicable Standard Requirement or in the filed Outline of Production, a live virus vaccine shall meet...

  2. 9 CFR 113.71 - Chlamydia Psittaci Vaccine (Feline Pneumonitis), Live Chlamydia.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 9 Animals and Animal Products 1 2014-01-01 2014-01-01 false Chlamydia Psittaci Vaccine (Feline... VECTORS STANDARD REQUIREMENTS Live Bacterial Vaccines § 113.71 Chlamydia Psittaci Vaccine (Feline Pneumonitis), Live Chlamydia. Chlamydia Psittaci Vaccine (Feline Pneumonitis), Live Chlamydia, shall...

  3. 9 CFR 113.300 - General requirements for live virus vaccines.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... vaccines. 113.300 Section 113.300 Animals and Animal Products ANIMAL AND PLANT HEALTH INSPECTION SERVICE... REQUIREMENTS Live Virus Vaccines § 113.300 General requirements for live virus vaccines. When prescribed in an applicable Standard Requirement or in the filed Outline of Production, a live virus vaccine shall meet...

  4. 9 CFR 113.71 - Chlamydia Psittaci Vaccine (Feline Pneumonitis), Live Chlamydia.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 9 Animals and Animal Products 1 2010-01-01 2010-01-01 false Chlamydia Psittaci Vaccine (Feline... VECTORS STANDARD REQUIREMENTS Live Bacterial Vaccines § 113.71 Chlamydia Psittaci Vaccine (Feline Pneumonitis), Live Chlamydia. Chlamydia Psittaci Vaccine (Feline Pneumonitis), Live Chlamydia, shall...

  5. 9 CFR 113.71 - Chlamydia Psittaci Vaccine (Feline Pneumonitis), Live Chlamydia.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 9 Animals and Animal Products 1 2012-01-01 2012-01-01 false Chlamydia Psittaci Vaccine (Feline... VECTORS STANDARD REQUIREMENTS Live Bacterial Vaccines § 113.71 Chlamydia Psittaci Vaccine (Feline Pneumonitis), Live Chlamydia. Chlamydia Psittaci Vaccine (Feline Pneumonitis), Live Chlamydia, shall...

  6. 9 CFR 113.300 - General requirements for live virus vaccines.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... vaccines. 113.300 Section 113.300 Animals and Animal Products ANIMAL AND PLANT HEALTH INSPECTION SERVICE... REQUIREMENTS Live Virus Vaccines § 113.300 General requirements for live virus vaccines. When prescribed in an applicable Standard Requirement or in the filed Outline of Production, a live virus vaccine shall meet...

  7. Protection Against Dengue Virus by Non-Replicating and Live Attenuated Vaccines Used Together in a Prime Boost Vaccination Strategy

    DTIC Science & Technology

    2010-01-01

    Protection against dengue virus by non-replicating and live attenuated vaccines used together in a prime boost vaccination strategy Monika Simmons a...Dengue DNA Punfied inacdvared virus Uvc artenuatcd virus Jlnmc boost A new vaccination strategy for dengue virus (DENV) was eval uated in rhesus...region (TDNA) then boosting 2 months l,ltcr with a tetravalent live aucnuated virus (TLAV) vaccine . Both vaccine combinations elicited virus

  8. Herpes Simplex Vaccines: Prospects of Live-attenuated HSV Vaccines to Combat Genital and Ocular infections.

    PubMed

    Stanfield, Brent; Kousoulas, Konstantin Gus

    2015-09-01

    Herpes simplex virus type-1 (HSV-1) and its closely related type-2 (HSV-2) viruses cause important clinical manifestations in humans including acute ocular disease and genital infections. These viruses establish latency in the trigeminal ganglionic and dorsal root neurons, respectively. Both viruses are widespread among humans and can frequently reactivate from latency causing disease. Currently, there are no vaccines available against herpes simplex viral infections. However, a number of promising vaccine approaches are being explored in pre-clinical investigations with few progressing to early phase clinical trials. Consensus research findings suggest that robust humoral and cellular immune responses may partially control the frequency of reactivation episodes and reduce clinical symptoms. Live-attenuated viral vaccines have long been considered as a viable option for generating robust and protective immune responses against viral pathogens. Varicella zoster virus (VZV) belongs to the same alphaherpesvirus subfamily with herpes simplex viruses. A live-attenuated VZV vaccine has been extensively used in a prophylactic and therapeutic approach to combat primary and recurrent VZV infection indicating that a similar vaccine approach may be feasible for HSVs. In this review, we summarize pre-clinical approaches to HSV vaccine development and current efforts to test certain vaccine approaches in human clinical trials. Also, we discuss the potential advantages of using a safe, live-attenuated HSV-1 vaccine strain to protect against both HSV-1 and HSV-2 infections.

  9. Ovine Enzootic Abortion (OEA): a comparison of antibody responses in vaccinated and naturally-infected swiss sheep over a two year period

    PubMed Central

    Gerber, Andrea; Thoma, Ruedi; Vretou, Evangelia; Psarrou, Evgenia; Kaiser, Carmen; Doherr, Marcus G; Zimmermann, Dieter R; Polkinghorne, Adam; Pospischil, Andreas; Borel, Nicole

    2007-01-01

    Background Prevention and control of ovine enzootic abortion (OEA) can be achieved by application of a live vaccine. In this study, five sheep flocks with different vaccination and infection status were serologically tested using a competitive enzyme-linked immunosorbent assay (cELISA) specific for Chlamydophila (Cp.) abortus over a two-year time period. Results Sheep in Flock A with recent OEA history had high antibody values after vaccination similar to Flock C with natural Cp. abortus infections. In contrast, OEA serology negative sheep (Flock E) showed individual animal-specific immunoreactions after vaccination. Antibody levels of vaccinated ewes in Flock B ranged from negative to positive two and three years after vaccination, respectively. Positive antibody values in the negative control Flock D (without OEA or vaccination) are probably due to asymptomatic intestinal infections with Cp. abortus. Excretion of the attenuated strain of Cp. abortus used in the live vaccine through the eye was not observed in vaccinated animals of Flock E. Conclusion The findings of our study indicate that, using serology, no distinction can be made between vaccinated and naturally infected sheep. As a result, confirmation of a negative OEA status in vaccinated animals by serology cannot be determined. PMID:17903243

  10. Live vaccines for human metapneumovirus designed by reverse genetics.

    PubMed

    Buchholz, Ursula J; Nagashima, Kunio; Murphy, Brian R; Collins, Peter L

    2006-10-01

    Human metapneumovirus (HMPV) was first described in 2001 and has quickly become recognized as an important cause of respiratory tract disease worldwide, especially in the pediatric population. A vaccine against HMPV is required to prevent severe disease associated with infection in infancy. The primary strategy is to develop a live-attenuated virus for intranasal immunization, which is particularly well suited against a respiratory virus. Reverse genetics provides a means of developing highly characterized 'designer' attenuated vaccine candidates. To date, several promising vaccine candidates have been developed, each using a different mode of attenuation. One candidate involves deletion of the G glycoprotein, providing attenuation that is probably based on reduced efficiency of attachment. A second candidate involves deletion of the M2-2 protein, which participates in regulating RNA synthesis and whose deletion has the advantageous property of upregulating transcription and increasing antigen synthesis. A third candidate involves replacing the P protein gene of HMPV with its counterpart from the related avian metapneumovirus, thereby introducing attenuation owing to its chimeric nature and host range restriction. Another live vaccine strategy involves using an attenuated parainfluenza virus as a vector to express HMPV protective antigens, providing a bivalent pediatric vaccine. Additional modifications to provide improved vaccines will also be discussed.

  11. Freeze-drying of live virus vaccines: A review.

    PubMed

    Hansen, L J J; Daoussi, R; Vervaet, C; Remon, J-P; De Beer, T R M

    2015-10-13

    Freeze-drying is the preferred method for stabilizing live, attenuated virus vaccines. After decades of research on several aspects of the process like the stabilization and destabilization mechanisms of the live, attenuated viruses during freeze-drying, the optimal formulation components and process settings are still matter of research. The molecular complexity of live, attenuated viruses, the multiple destabilization pathways and the lack of analytical techniques allowing the measurement of physicochemical changes in the antigen's structure during and after freeze-drying mean that they form a particular lyophilization challenge. The purpose of this review is to overview the available information on the development of the freeze-drying process of live, attenuated virus vaccines, herewith focusing on the freezing and drying stresses the viruses can undergo during processing as well as on the mechanisms and strategies (formulation and process) that are used to stabilize them during freeze-drying.

  12. Demystifying FluMist, a new intranasal, live influenza vaccine.

    PubMed

    Mossad, Sherif B

    2003-09-01

    FluMist--a cold-adapted, live-attenuated, trivalent, intranasal influenza virus vaccine approved by the US Food and Drug Administration on June 17, 2003--has been shown to be safe and effective, but its role in the general prevention of influenza is yet to be defined. Intranasal administration is expected to be more acceptable than parenteral, particularly in children, but the potential for the shedding of live virus may pose a risk to anyone with a compromised immune system.

  13. Global antibody response to Staphylococcus aureus live-cell vaccination.

    PubMed

    Selle, Martina; Hertlein, Tobias; Oesterreich, Babett; Klemm, Theresa; Kloppot, Peggy; Müller, Elke; Ehricht, Ralf; Stentzel, Sebastian; Bröker, Barbara M; Engelmann, Susanne; Ohlsen, Knut

    2016-04-22

    The pathogen Staphylococcus aureus causes a broad range of severe diseases and is feared for its ability to rapidly develop resistance to antibiotic substances. The increasing number of highly resistant S. aureus infections has accelerated the search for alternative treatment options to close the widening gap in anti-S. aureus therapy. This study analyses the humoral immune response to vaccination of Balb/c mice with sublethal doses of live S. aureus. The elicited antibody pattern in the sera of intravenously and intramuscularly vaccinated mice was determined using of a recently developed protein array. We observed a specific antibody response against a broad set of S. aureus antigens which was stronger following i.v. than i.m. vaccination. Intravenous but not intramuscular vaccination protected mice against an intramuscular challenge infection with a high bacterial dose. Vaccine protection was correlated with the strength of the anti-S. aureus antibody response. This study identified novel vaccine candidates by using protein microarrays as an effective tool and showed that successful vaccination against S. aureus relies on the optimal route of administration.

  14. Global antibody response to Staphylococcus aureus live-cell vaccination

    PubMed Central

    Selle, Martina; Hertlein, Tobias; Oesterreich, Babett; Klemm, Theresa; Kloppot, Peggy; Müller, Elke; Ehricht, Ralf; Stentzel, Sebastian; Bröker, Barbara M.; Engelmann, Susanne; Ohlsen, Knut

    2016-01-01

    The pathogen Staphylococcus aureus causes a broad range of severe diseases and is feared for its ability to rapidly develop resistance to antibiotic substances. The increasing number of highly resistant S. aureus infections has accelerated the search for alternative treatment options to close the widening gap in anti-S. aureus therapy. This study analyses the humoral immune response to vaccination of Balb/c mice with sublethal doses of live S. aureus. The elicited antibody pattern in the sera of intravenously and intramuscularly vaccinated mice was determined using of a recently developed protein array. We observed a specific antibody response against a broad set of S. aureus antigens which was stronger following i.v. than i.m. vaccination. Intravenous but not intramuscular vaccination protected mice against an intramuscular challenge infection with a high bacterial dose. Vaccine protection was correlated with the strength of the anti-S. aureus antibody response. This study identified novel vaccine candidates by using protein microarrays as an effective tool and showed that successful vaccination against S. aureus relies on the optimal route of administration. PMID:27103319

  15. HPV Vaccine Awareness and Knowledge Among Women Living with HIV.

    PubMed

    Wigfall, L T; Bynum, S A; Brandt, H M; Hébert, J R

    2016-03-01

    Cervical cancer risk is increased among women living with HIV (WLH). Human papillomavirus (HPV) vaccination has been shown to be safe and immunogenic among WLH. We examined HPV vaccine awareness and HPV knowledge among WLH. This cross-sectional study collected data from 145 WLH between March 2011 and April 2012. An interviewer-administered survey assessed HPV vaccine awareness and knowledge. Stata/IC 13 was used to perform chi-square tests and multivariate logistic regression analyses. Our sample was 90 % non-Hispanic black and 64 % earned <$10,000/year. Few (38 %) had heard of the HPV vaccine. Half (50 %) knew that HPV caused cervical cancer. HPV vaccine awareness was ten times higher among WLH who knew HPV caused cervical cancer (OR = 10.17; 95 % CI 3.82-27.06). HPV vaccine awareness is low among WLH. Cancer prevention efforts aimed at raising awareness about the HPV vaccine and increasing knowledge about HPV are necessary first steps in reducing cervical cancer disparities among WLH.

  16. U-Omp19 from Brucella abortus Is a Useful Adjuvant for Vaccine Formulations against Salmonella Infection in Mice

    PubMed Central

    Risso, Gabriela S.; Carabajal, Marianela V.; Bruno, Laura A.; Ibañez, Andrés E.; Coria, Lorena M.; Pasquevich, Karina A.; Lee, Seung-Joo; McSorley, Stephen J.; Briones, Gabriel; Cassataro, Juliana

    2017-01-01

    Most pathogens infect through mucosal surfaces, and parenteral immunization typically fails to induce effective immune responses at these sites. Development of oral-administered vaccines capable of inducing mucosal as well as systemic immunity while bypassing the issues of antigen degradation and immune tolerance could be crucial for the control of enteropathogens. This study demonstrates that U-Omp19, a bacterial protease inhibitor with immunostimulatory features, coadministered with Salmonella antigens by the oral route, enhances mucosal and systemic immune responses in mice. U-Omp19 was able to increase antigen-specific production of IFN-γ and IL-17 and mucosal (IgA) antibody response. Finally, oral vaccination with U-Omp19 plus Salmonella antigens conferred protection against virulent challenge with Salmonella Typhimurium, with a significant reduction in bacterial loads. These findings prove the efficacy of this novel adjuvant in the Salmonella infection model and support the potential of U-Omp19 as a suitable adjuvant in oral vaccine formulations against mucosal pathogens requiring T helper (Th)1–Th17 protective immune responses. PMID:28261222

  17. U-Omp19 from Brucella abortus Is a Useful Adjuvant for Vaccine Formulations against Salmonella Infection in Mice.

    PubMed

    Risso, Gabriela S; Carabajal, Marianela V; Bruno, Laura A; Ibañez, Andrés E; Coria, Lorena M; Pasquevich, Karina A; Lee, Seung-Joo; McSorley, Stephen J; Briones, Gabriel; Cassataro, Juliana

    2017-01-01

    Most pathogens infect through mucosal surfaces, and parenteral immunization typically fails to induce effective immune responses at these sites. Development of oral-administered vaccines capable of inducing mucosal as well as systemic immunity while bypassing the issues of antigen degradation and immune tolerance could be crucial for the control of enteropathogens. This study demonstrates that U-Omp19, a bacterial protease inhibitor with immunostimulatory features, coadministered with Salmonella antigens by the oral route, enhances mucosal and systemic immune responses in mice. U-Omp19 was able to increase antigen-specific production of IFN-γ and IL-17 and mucosal (IgA) antibody response. Finally, oral vaccination with U-Omp19 plus Salmonella antigens conferred protection against virulent challenge with Salmonella Typhimurium, with a significant reduction in bacterial loads. These findings prove the efficacy of this novel adjuvant in the Salmonella infection model and support the potential of U-Omp19 as a suitable adjuvant in oral vaccine formulations against mucosal pathogens requiring T helper (Th)1-Th17 protective immune responses.

  18. 9 CFR 113.64 - General requirements for live bacterial vaccines.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... bacterial vaccines. 113.64 Section 113.64 Animals and Animal Products ANIMAL AND PLANT HEALTH INSPECTION... STANDARD REQUIREMENTS Live Bacterial Vaccines § 113.64 General requirements for live bacterial vaccines... bacterial vaccine shall meet the requirements in this section. (a) Purity test. Final container samples...

  19. 9 CFR 113.64 - General requirements for live bacterial vaccines.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... bacterial vaccines. 113.64 Section 113.64 Animals and Animal Products ANIMAL AND PLANT HEALTH INSPECTION... STANDARD REQUIREMENTS Live Bacterial Vaccines § 113.64 General requirements for live bacterial vaccines... bacterial vaccine shall meet the requirements in this section. (a) Purity test. Final container samples...

  20. 9 CFR 113.64 - General requirements for live bacterial vaccines.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... bacterial vaccines. 113.64 Section 113.64 Animals and Animal Products ANIMAL AND PLANT HEALTH INSPECTION... STANDARD REQUIREMENTS Live Bacterial Vaccines § 113.64 General requirements for live bacterial vaccines... bacterial vaccine shall meet the requirements in this section. (a) Purity test. Final container samples...

  1. 9 CFR 113.64 - General requirements for live bacterial vaccines.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... bacterial vaccines. 113.64 Section 113.64 Animals and Animal Products ANIMAL AND PLANT HEALTH INSPECTION... STANDARD REQUIREMENTS Live Bacterial Vaccines § 113.64 General requirements for live bacterial vaccines... bacterial vaccine shall meet the requirements in this section. (a) Purity test. Final container samples...

  2. 9 CFR 113.64 - General requirements for live bacterial vaccines.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... bacterial vaccines. 113.64 Section 113.64 Animals and Animal Products ANIMAL AND PLANT HEALTH INSPECTION... STANDARD REQUIREMENTS Live Bacterial Vaccines § 113.64 General requirements for live bacterial vaccines... bacterial vaccine shall meet the requirements in this section. (a) Purity test. Final container samples...

  3. Use of S-[2,3-bispalmitoyiloxy-(2R)-propyl]-R-cysteinyl-amido-monomethoxy polyethylene glycol as an adjuvant improved protective immunity associated with a DNA vaccine encoding Cu,Zn superoxide dismutase of Brucella abortus in mice.

    PubMed

    Retamal-Díaz, Angello; Riquelme-Neira, Roberto; Sáez, Darwin; Rivera, Alejandra; Fernández, Pablo; Cabrera, Alex; Guzmán, Carlos A; Oñate, Angel

    2014-11-01

    This study was conducted to evaluate the immunogenicity and protective efficacy of a DNA vaccine encoding Brucella abortus Cu,Zn superoxide dismutase (SOD) using the Toll-like receptor 2/6 agonist S-[2,3-bispalmitoyiloxy-(2R)-propyl]-R-cysteinyl-amido-monomethoxy polyethylene glycol (BPPcysMPEG) as an adjuvant. Intranasal coadministration of BPPcysMPEG with a plasmid carrying the SOD-encoding gene (pcDNA-SOD) into BALB/c mice elicited antigen-specific humoral and cellular immune responses. Humoral responses were characterized by the stimulation of IgG2a and IgG1 and by the presence of SOD-specific secretory IgA in nasal and bronchoalveolar lavage fluids. Furthermore, T-cell proliferative responses and increased production of gamma interferon were also observed upon splenocyte restimulation with recombinant SOD. Cytotoxic responses were also stimulated, as demonstrated by the lysis of RB51-SOD-infected J774.A1 macrophages by cells recovered from immunized mice. The pcDNA-SOD/BPPcysMPEG formulation induced improved protection against challenge with the virulent strain B. abortus 2308 in BALB/c mice over that provided by pcDNA-SOD, suggesting the potential of this vaccination strategy against Brucella infection.

  4. [Live attenuated and inactivated influenza vaccines: data from direct comparative studies].

    PubMed

    Kashirina, O S; Vasil'ev, Iu M

    2014-01-01

    Comparative evaluation of live attenuated and inactivated influenza vaccines based on data from direct comparative studies is necessary for ensuring the most effective and safe vaccination against influenza. Analysis of direct comparative preclinical and clinical studies of inactivated and live cold-adapted (ca) influenza vaccines showed that published data are inconsistent and limited for some population groups. Live ca vaccines may be promising as an alternative or addition to inactivated vaccines especially for mass vaccination against influenza in children as well as in the elderly when combined with inactivated vaccines. Further studies of inactivated and live ca influenza vaccines in direct comparative studies that control the administration route and vaccine strain production as well as development and confirmation of objective criteria of live attenuated influenza vaccine effectiveness evaluation are necessary.

  5. Safety of a live attenuated Erysipelothrix rhusiopathiae vaccine for swine.

    PubMed

    Neumann, Eric J; Grinberg, Alex; Bonistalli, Kathryn N; Mack, Hamish J; Lehrbach, Philip R; Gibson, Nicole

    2009-03-30

    Infection with Erysipelothrix rhusiopathiae has a significant economic impact on pig production systems worldwide. Both inactivated and attenuated vaccines are available to prevent development of clinical signs of swine erysipelas. The ability of a live attenuated E. rhusiopathiae strain to become persistently established in pigs after intranasal exposure and its potential to cause clinical signs consistent with swine erysipelas after being administered directly into the nasopharynx of healthy pigs was evaluated. Five, E. rhusiopathiae-negative pigs were vaccinated by deep intranasal inoculation then followed for 14 days. Nasal swabs were collected daily for 5 days and clinical observations were made daily for 14 days post-vaccination. Nasal swabs were cultured for E. rhusiopathiae with the intent of back-passaging any recovered organisms into subsequent replicates. No organism was recovered from nasal swabs in the first vaccination replicate. A second replicate including 10 pigs was initiated and followed in an identical manner to that described above. Again, no E. rhusiopathiae was recovered from any pigs. No pigs in either replicate showed any signs of clinical swine erysipelas. The live attenuated E. rhusiopathiae strain evaluated in this study did not appear to become persistently established in pigs post-vaccination, did not cause any local or systemic signs consistent with swine erysipelas, and was therefore unlikely to revert to a virulent state when used in a field setting.

  6. In-Depth Characterization of Live Vaccines Used in Europe for Oral Rabies Vaccination of Wildlife

    PubMed Central

    Cliquet, Florence; Picard-Meyer, Evelyne; Mojzis, Miroslav; Dirbakova, Zuzana; Muizniece, Zita; Jaceviciene, Ingrida; Mutinelli, Franco; Matulova, Marta; Frolichova, Jitka; Rychlik, Ivan; Celer, Vladimir

    2015-01-01

    Although rabies incidence has fallen sharply over the past decades in Europe, the disease is still present in Eastern Europe. Oral rabies immunization of wild animal rabies has been shown to be the most effective method for the control and elimination of rabies. All rabies vaccines used in Europe are modified live virus vaccines based on the Street Alabama Dufferin (SAD) strain isolated from a naturally-infected dog in 1935. Because of the potential safety risk of a live virus which could revert to virulence, the genetic composition of three commercial attenuated live rabies vaccines was investigated in two independent laboratories using next genome sequencing. This study is the first one reporting on the diversity of variants in oral rabies vaccines as well as the presence of a mix of at least two different variants in all tested batches. The results demonstrate the need for vaccine producers to use new robust methodologies in the context of their routine vaccine quality controls prior to market release. PMID:26509266

  7. In-Depth Characterization of Live Vaccines Used in Europe for Oral Rabies Vaccination of Wildlife.

    PubMed

    Cliquet, Florence; Picard-Meyer, Evelyne; Mojzis, Miroslav; Dirbakova, Zuzana; Muizniece, Zita; Jaceviciene, Ingrida; Mutinelli, Franco; Matulova, Marta; Frolichova, Jitka; Rychlik, Ivan; Celer, Vladimir

    2015-01-01

    Although rabies incidence has fallen sharply over the past decades in Europe, the disease is still present in Eastern Europe. Oral rabies immunization of wild animal rabies has been shown to be the most effective method for the control and elimination of rabies. All rabies vaccines used in Europe are modified live virus vaccines based on the Street Alabama Dufferin (SAD) strain isolated from a naturally-infected dog in 1935. Because of the potential safety risk of a live virus which could revert to virulence, the genetic composition of three commercial attenuated live rabies vaccines was investigated in two independent laboratories using next genome sequencing. This study is the first one reporting on the diversity of variants in oral rabies vaccines as well as the presence of a mix of at least two different variants in all tested batches. The results demonstrate the need for vaccine producers to use new robust methodologies in the context of their routine vaccine quality controls prior to market release.

  8. Efficacy of HVT-IBD vector vaccine compared to attenuated live vaccine using in-ovo vaccination against a Korean very virulent IBDV in commercial broiler chickens.

    PubMed

    Roh, J-H; Kang, M; Wei, B; Yoon, R-H; Seo, H-S; Bahng, J-Y; Kwon, J-T; Cha, S-Y; Jang, H-K

    2016-05-01

    The production performance, efficacy, and safety of two types of vaccines for infectious bursal disease virus (IBDV) were compared with in-ovo vaccination of Cobb 500 broiler chickens for gross and microscopic examination of the bursa of Fabricius, bursa/body weight (b/B) ratio, flow cytometry, and serologic response to Newcastle disease virus (NDV) vaccination. One vaccine was a recombinant HVT-IBD vector vaccine (HVT as for herpesvirus of turkeys) and the other was an intermediate plus live IBDV vaccine. A significant difference was detected at 21 d. Eight of 10 chickens that received the IBDV live vaccine had severe bursal lesions and a relatively low b/B ratio of 0.95, and an inhibited NDV vaccine response. On the other hand, the HVT-IBD vector vaccine resulted in mild bursal lesions and a b/B ratio of 1.89. Therefore, the live vaccine had lower safety than that of the HVT-IBD vector vaccine. To determine the protective efficacy, chickens were intraocularly challenged at 24 d. Eight of 10 chickens in the IBDV live vaccination group showed gross and histological lesions characterized by hemorrhage, cyst formation, lymphocytic depletion, and a decreased b/B ratio. In contrast, the HVT-IBD vector vaccinated chickens showed mild gross and histological lesions in three of 10 chickens with a b/B ratio of 1.36, which was similar to that of the unchallenged controls. Vaccinated chickens showed a significant increase in IBDV antibody titers, regardless of the type of vaccine used. In addition, significantly better broiler flock performance was observed with the HVT-IBD vector vaccine compared to that of the live vaccine. Our results revealed that the HVT-IBD vector vaccine could be used as an alternative vaccine to increase efficacy, and to have an improved safety profile compared with the IBDV live vaccine using in-ovo vaccination against the Korean very virulent IBDV in commercial broiler chickens.

  9. Clinical trials of live oral rotavirus vaccines: the Finnish experience.

    PubMed

    Vesikari, T

    1993-01-01

    Live oral candidate rotavirus vaccines of bovine (RIT 4237) or rhesus (RRV-1) origin and reassortants of RRV-1 expressing human serotype 1 (DxRRV) or serotype 2 (DS1xRRV) VP7 protein were evaluated for clinical efficacy in young children in successive trials from 1983 to 1989. In each study, the vaccinations were given before a rotavirus epidemic season and the follow-up of vaccinees covered two rotavirus epidemic seasons lasting up to 2-3 years of age. Serotype 1 rotavirus was predominant in each season. Protection rates against all rotavirus-associated diarrhoea ranged from 0 to 67% but were higher, up to 100%, against more severe rotavirus disease. All tested vaccines also showed efficacy for diarrhoea not apparently associated with rotavirus; therefore the clinical benefit of the vaccinations was greater than could be deduced from efficacy rates for rotavirus-associated diarrhoea alone. Each of the candidate vaccines could significantly reduce severe diarrhoea in Finnish children in the first 2 to 3 years of life. For optimal efficacy, the vaccines should be administered in the autumn before the regular epidemic season of rotavirus.

  10. A candidate live inactivatable attenuated vaccine for AIDS.

    PubMed Central

    Chakrabarti, B K; Maitra, R K; Ma, X Z; Kestler, H W

    1996-01-01

    The recent discovery of long term AIDS nonprogressors who harbor nef-attenuated HIV suggests that a naturally occurring live vaccine for AIDS may already exist. Animal models have shown that a live vaccine for AIDS, attenuated in nef, is the best candidate vaccine. There are considerable risks, real and perceived, with the use of live HIV vaccines. We have introduced a conditional lethal genetic element into HIV-1 and simian immunodeficiency virus (SIV) molecular clones deleted in nef. The antiviral strategy we employed targets both virus replication and the survival of the infected cell. The suicide gene, herpes simplex virus thymidine kinase (tk), was expressed and maintained in HIV over long periods of time. Herpes simplex virus tk confers sensitivity to the antiviral activity of acyclic nucleosides such as ganciclovir (GCV). HIV-tk and SIV-tk replication were sensitive to GCV at subtoxic concentrations, and virus-infected cells were eliminated from tumor cell lines as well as primary cell cultures. We found the HIV-tk virus to be remarkably stable even after being cultured in media containing a low concentration of GCV and then challenged with the higher dose and that while GCV resistant escape mutants did arise, a significant fraction of the virus remained sensitive to GCV. Images Fig. 1 Fig. 5 PMID:8790413

  11. 9 CFR 113.26 - Detection of viable bacteria and fungi except in live vaccine.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 9 Animals and Animal Products 1 2010-01-01 2010-01-01 false Detection of viable bacteria and fungi except in live vaccine. 113.26 Section 113.26 Animals and Animal Products ANIMAL AND PLANT HEALTH... in live vaccine. Each serial and subserial of biological product except live vaccines shall be...

  12. 9 CFR 113.27 - Detection of extraneous viable bacteria and fungi in live vaccines.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... bacteria and fungi in live vaccines. 113.27 Section 113.27 Animals and Animal Products ANIMAL AND PLANT... bacteria and fungi in live vaccines. Unless otherwise specified by the Administrator or elsewhere exempted in this part, each serial and subserial of live vaccine and each lot of Master Seed Virus and...

  13. 9 CFR 113.26 - Detection of viable bacteria and fungi except in live vaccine.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 9 Animals and Animal Products 1 2011-01-01 2011-01-01 false Detection of viable bacteria and fungi except in live vaccine. 113.26 Section 113.26 Animals and Animal Products ANIMAL AND PLANT HEALTH... in live vaccine. Each serial and subserial of biological product except live vaccines shall be...

  14. 9 CFR 113.27 - Detection of extraneous viable bacteria and fungi in live vaccines.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... bacteria and fungi in live vaccines. 113.27 Section 113.27 Animals and Animal Products ANIMAL AND PLANT... bacteria and fungi in live vaccines. Unless otherwise specified by the Administrator or elsewhere exempted in this part, each serial and subserial of live vaccine and each lot of Master Seed Virus and...

  15. 9 CFR 113.27 - Detection of extraneous viable bacteria and fungi in live vaccines.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... bacteria and fungi in live vaccines. 113.27 Section 113.27 Animals and Animal Products ANIMAL AND PLANT... bacteria and fungi in live vaccines. Unless otherwise specified by the Administrator or elsewhere exempted in this part, each serial and subserial of live vaccine and each lot of Master Seed Virus and...

  16. 9 CFR 113.27 - Detection of extraneous viable bacteria and fungi in live vaccines.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... bacteria and fungi in live vaccines. 113.27 Section 113.27 Animals and Animal Products ANIMAL AND PLANT... bacteria and fungi in live vaccines. Unless otherwise specified by the Administrator or elsewhere exempted in this part, each serial and subserial of live vaccine and each lot of Master Seed Virus and...

  17. 9 CFR 113.26 - Detection of viable bacteria and fungi except in live vaccine.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 9 Animals and Animal Products 1 2013-01-01 2013-01-01 false Detection of viable bacteria and fungi except in live vaccine. 113.26 Section 113.26 Animals and Animal Products ANIMAL AND PLANT HEALTH... in live vaccine. Each serial and subserial of biological product except live vaccines shall be...

  18. 9 CFR 113.27 - Detection of extraneous viable bacteria and fungi in live vaccines.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... bacteria and fungi in live vaccines. 113.27 Section 113.27 Animals and Animal Products ANIMAL AND PLANT... bacteria and fungi in live vaccines. Unless otherwise specified by the Administrator or elsewhere exempted in this part, each serial and subserial of live vaccine and each lot of Master Seed Virus and...

  19. 9 CFR 113.26 - Detection of viable bacteria and fungi except in live vaccine.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 9 Animals and Animal Products 1 2014-01-01 2014-01-01 false Detection of viable bacteria and fungi except in live vaccine. 113.26 Section 113.26 Animals and Animal Products ANIMAL AND PLANT HEALTH... in live vaccine. Each serial and subserial of biological product except live vaccines shall be...

  20. 9 CFR 113.26 - Detection of viable bacteria and fungi except in live vaccine.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 9 Animals and Animal Products 1 2012-01-01 2012-01-01 false Detection of viable bacteria and fungi except in live vaccine. 113.26 Section 113.26 Animals and Animal Products ANIMAL AND PLANT HEALTH... in live vaccine. Each serial and subserial of biological product except live vaccines shall be...

  1. Skin vaccination with live virus vectored microneedle arrays induce long lived CD8(+) T cell memory.

    PubMed

    Becker, Pablo D; Hervouet, Catherine; Mason, Gavin M; Kwon, Sung-Yun; Klavinskis, Linda S

    2015-09-08

    A simple dissolvable microneedle array (MA) platform has emerged as a promising technology for vaccine delivery, due to needle-free injection with a formulation that preserves the immunogenicity of live viral vectored vaccines dried in the MA matrix. While recent studies have focused largely on design parameters optimized to induce primary CD8(+) T cell responses, the hallmark of a vaccine is synonymous with engendering long-lasting memory. Here, we address the capacity of dried MA vaccination to programme phenotypic markers indicative of effector/memory CD8(+) T cell subsets and also responsiveness to recall antigen benchmarked against conventional intradermal (ID) injection. We show that despite a slightly lower frequency of dividing T cell receptor transgenic CD8(+) T cells in secondary lymphoid tissue at an early time point, the absolute number of CD8(+) T cells expressing an effector memory (CD62L(-)CD127(+)) and central memory (CD62L(+)CD127(+)) phenotype during peak expansion were comparable after MA and ID vaccination with a recombinant human adenovirus type 5 vector (AdHu5) encoding HIV-1 gag. Similarly, both vaccination routes generated CD8(+) memory T cell subsets detected in draining LNs for at least two years post-vaccination capable of responding to secondary antigen. These data suggest that CD8(+) T cell effector/memory generation and long-term memory is largely unaffected by physical differences in vaccine delivery to the skin via dried MA or ID suspension.

  2. Brucella abortusΔcydCΔcydD and ΔcydCΔpurD double-mutants are highly attenuated and confer long-term protective immunity against virulent Brucella abortus.

    PubMed

    Truong, Quang Lam; Cho, Youngjae; Park, Soyeon; Kim, Kiju; Hahn, Tae-Wook

    2016-01-04

    We constructed double deletion (ΔcydCΔcydD and ΔcydCΔpurD) mutants from virulent Brucella abortus biovar 1 field isolate (BA15) by deleting the genes encoding an ATP-binding cassette-type transporter (cydC and cydD genes) and a phosphoribosylamine-glycine ligase (purD). Both BA15ΔcydCΔcydD and BA15ΔcydCΔpurD double-mutants exhibited significant attenuation of virulence when assayed in murine macrophages or in BALB/c mice. Both double-mutants were readily cleared from spleens by 4 weeks post-inoculation even when inoculated at the dose of 10(8) CFU per mouse. Moreover, the inoculated mice showed no splenomegaly, which indicates that the mutants are highly attenuated. Importantly, the attenuation of in vitro and in vivo growth did not impair the ability of these mutants to confer long-term protective immunity in mice against challenge with B. abortus strain 2308. Vaccination of mice with either mutant induced humoral and cell-mediated immune responses, and provided significantly better protection than commercial B. abortus strain RB51 vaccine. These results suggest that highly attenuated BA15ΔcydCΔcydD and BA15ΔcydCΔpurD mutants can be used effectively as potential live vaccine candidates against bovine brucellosis.

  3. Antibody Response to Live Attenuated Vaccines in Adults in Japan

    PubMed Central

    Uchiyama-Nakamura, Fukumi; Sugata-Tsubaki, Aiko; Yamada, Yutaka; Uno, Kenji; Kasahara, Kei; Maeda, Koichi; Konishi, Mitsuru; Mikasa, Keiichi

    2016-01-01

    Abstract The purpose of this study was to examine the efficacy rendered with a single dose of live attenuated measles, rubella, mumps, and varicella containing vaccine. We inoculated healthcare workers (HCWs) with a single dose of vaccine to a disease lacking in antibody titer for those not meeting the criteria of our hospital (measles: <16.0 (IgG enzyme immunoassay (EIA)), rubella: ≤1:32 (hemagglutination-inhibition), mumps: <4.0 (IgG EIA), and varicella: <4.0 (IgG EIA)). At 28–60 days after vaccination, the antibody titer was tested again. We included 48 HCWs. A total of 32, 15, 31, and 10 individuals were inoculated with a single dose of measles-containing, rubella-containing, mumps, or varicella vaccine, respectively, and showed significant antibody elevation (9.2 ± 12.3 to 27.6 ± 215.6, p<0.001; 8 ± 1.2 to 32 ± 65.5, p<0.001; 3.0 ± 1.0 to 13.1 ± 8.6, p<0.05; and 2.6 ± 1.3 to 11.8 ± 8.1, p<0.001, respectively). Major side effects were not observed. In a limited population, a single dose of live attenuated vaccine showed elevation of antibody titer without any severe adverse reactions. However, whether the post-vaccination response rate criteria of our university was fulfilled could not be determined owing to limited sample size. PMID:28352840

  4. Antibody response of cattle to vaccination with commercial modified live rabies vaccines in Guatemala.

    PubMed

    Gilbert, Amy; Greenberg, Lauren; Moran, David; Alvarez, Danilo; Alvarado, Marlon; Garcia, Daniel L; Peruski, Leonard

    2015-01-01

    Vampire bat rabies is a public and animal health concern throughout Latin America. As part of an ecological study of vampire bat depredation on cattle in southern Guatemala, we conducted a vaccine seroconversion study among three dairy farms. The main objectives of this cross sectional and cohort study were to understand factors associated with bat bites among cattle, to determine whether unvaccinated cattle had evidence of rabies virus exposure and evaluate whether exposure was related to bat bite prevalence, and to assess whether cattle demonstrate adequate seroconversion to two commercial vaccines used in Guatemala. In 2012, baseline blood samples were collected immediately prior to intramuscular inoculation of cattle with one of two modified live rabies vaccines. Post vaccination blood samples were collected 13 and 393 days later. Sera were tested for rabies virus neutralizing antibodies (rVNA) by the rapid fluorescent focus inhibition test (RFFIT). Across two years of study, 36% (254/702) of inspected cattle presented gross evidence of vampire bat bites. Individual cattle with a bat bite in 2012 were more likely have a bat bite in 2013. Prior to vaccination, 12% (42/350) of cattle sera demonstrated rVNA, but bite status in 2012 was not associated with presence of rVNA. Vaccine brand was the only factor associated with adequate rVNA response of cattle by day 13. However, vaccine brand and rVNA status at day 13 were associated with an adequate rVNA titer on day 393, with animals demonstrating an adequate titer at day 13 more likely to have an adequate titer at day 393. Our findings support stable levels of vampire bat depredation and evidence of rVNA in unvaccinated cattle. Brand of vaccine may be an important consideration impacting adequate rVNA response and long-term maintenance of rVNA in cattle. Further, the results demonstrate that initial response to vaccination is associated with rVNA status over one year following vaccination.

  5. Delta-pgm, a new live-attenuated vaccine against Brucella suis.

    PubMed

    Czibener, Cecilia; Del Giudice, Mariela Giselda; Spera, Juan Manuel; Fulgenzi, Fabiana Rosa; Ugalde, Juan Esteban

    2016-03-18

    Brucellosis is one of the most widespread zoonosis in the world affecting many domestic and wild animals including bovines, goats, pigs and dogs. Each species of the Brucella genus has a particular tropism toward different mammals being the most relevant for human health Brucella abortus, Brucella melitensis and Brucella suis that infect bovines, goats/camelids and swine respectively. Although for B. abortus and B. melitensis there are vaccines available, there is no efficient vaccine to protect swine from B. suis infection so far. We describe here the construction of a novel vaccine strain that confers excellent protection against B. suis in a mouse model of infection. This strain is a clean deletion of the phosphoglucomutase (pgm) gene that codes for a protein that catalyzes the conversion of glucose-6-P to glucose-1-P, which is used as a precursor for the biosynthesis of many polysaccharides. The Delta-pgm strain lacks a complete lipopolysaccharide, is unable to synthesize cyclic beta glucans and is sensitive to several detergents and Polymyxin B. We show that this strain replicates in cultured cells, is completely avirulent in the mouse model of infection but protects against a challenge of the virulent strain inducing the production of pro-inflammatory cytokines. This novel strain could be an excellent candidate for the control of swine brucellosis, a disease of emerging concern in many parts of the world.

  6. Comparison of Biological and Immunological Characterization of Lipopolysaccharides From Brucella abortus RB51 and S19

    PubMed Central

    Kianmehr, Zahra; Kaboudanian Ardestani, Sussan; Soleimanjahi, Hoorieh; Fotouhi, Fatemeh; Alamian, Saeed; Ahmadian, Shahin

    2015-01-01

    Background: Brucella abortus RB51 is a rough stable mutant strain, which has been widely used as a live vaccine for prevention of brucellosis in cattle instead of B. abortus strain S19. B. abortus lipopolysaccharide (LPS) has unique properties in comparison to other bacterial LPS. Objectives: In the current study, two types of LPS, smooth (S-LPS) and rough (R-LPS) were purified from B. abortus S19 and RB51, respectively. The aim of this study was to evaluate biological and immunological properties of purified LPS as an immunogenical determinant. Materials and Methods: Primarily, S19 and RB51 LPS were extracted and purified by two different modifications of the phenol water method. The final purity of LPS was determined by chemical analysis (2-keto-3-deoxyoctonate (KDO), glycan, phosphate and protein content) and different staining methods, following sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE). C57BL/6 mice were immunized subcutaneously three times at biweekly intervals with the same amount of purified LPSs. The humoral immunity was evaluated by measuring specific IgG levels and also different cytokine levels, such as IFN-γ, TNF-α, IL-4 and IL-10, were determined for assessing T-cell immune response. Results: Biochemical analysis data and SDS-PAGE profile showed that the chemical nature of S19 LPS is different from RB51 LPS. Both S and R-LPS induce an immune response. T-cell immune response induced by both S and R-LPS had almost the same pattern whereas S19 LPS elicited humoral immunity, which was higher than RB51 LPS. Conclusions: Purified LPS can be considered as a safe adjuvant and can be used as a component in prophylactic and therapeutic vaccines targeting infectious disease, cancer and allergies. PMID:26862376

  7. Clinical evaluation strategies for a live attenuated tetravalent dengue vaccine.

    PubMed

    Precioso, Alexander Roberto; Palacios, Ricardo; Thomé, Beatriz; Mondini, Gabriella; Braga, Patrícia; Kalil, Jorge

    2015-12-10

    Butantan Institute is a public Brazilian biomedical research-manufacturer center affiliated to the São Paulo State Secretary of Health. Currently, Butantan is one of the main public producers of vaccines, antivenoms, and antitoxins in Latin America. The partnership between Butantan and the National Institutes of Health (NIH) of the United Sates has been one of the longest and most successful partnerships in the development and manufacturing of new vaccines. Recently, Butantan Institute has developed and manufactured a lyophilized tetravalent live attenuated dengue vaccine with the four dengue viruses attenuated and licensed from the Laboratory of Infectious Diseases at The National Institutes of Allergy and Infectious Diseases (LID/NIAID/NIH). The objective of this paper is to describe the clinical evaluation strategies of a live attenuated tetravalent dengue vaccine (Butantan-DV) developed and manufactured by Butantan Institute. These clinical strategies will be used to evaluate the Butantan-DV Phase III trial to support the Butantan-DV licensure for protection against any symptomatic dengue caused by any serotype in people aged 2 to 59 years.

  8. Live attenuated vaccines: Historical successes and current challenges

    SciTech Connect

    Minor, Philip D.

    2015-05-15

    Live attenuated vaccines against human viral diseases have been amongst the most successful cost effective interventions in medical history. Smallpox was declared eradicated in 1980; poliomyelitis is nearing global eradication and measles has been controlled in most parts of the world. Vaccines function well for acute diseases such as these but chronic infections such as HIV are more challenging for reasons of both likely safety and probable efficacy. The derivation of the vaccines used has in general not been purely rational except in the sense that it has involved careful clinical trials of candidates and subsequent careful follow up in clinical use; the identification of the candidates is reviewed. - Highlights: • Live vaccines against human diseases caused by viruses have been very successful. • They have been developed by empirical clinical studies and problems identified in later use. • It can be difficult to balance ability to cause disease and ability to immunise for a strain. • There is currently no reliable basis for predicting success from pure virological studies. • Vaccinia, which eradicated smallpox, is the paradigm for all successes and issues.

  9. [Advantages and disadvantages of inactivated and live influenza vaccine].

    PubMed

    Gendon, Iu Z

    2004-01-01

    Published data related with comparison studies of safety, efficiency and some other properties of cold-adapted live influenza vaccine (LIV) and of inactivated influenza vaccine (IIV) are analyzed. LIV and IIV do not differ by systemic reactions after administration; however, it is not ruled out that there can be unfavorable reactions in vaccination of persons with allergy to the chicken-embryo proteins as well as in cases of persistence/reversion of cold-adapted strain observed in vaccination of persons with primary impairments of the immune system. There are no convincing data, up to now, on that LIV is superior to IIV in coping with influenza pandemics. The efficiency of LIV and IIV for children aged 3 years and more and for healthy adults is virtually identical. Additional controllable field comparative studies of LIV and IIV efficiency in immunization of elderly persons are needed. Limited data on LIV efficiency for children aged 2 months and more were obtained. The need in a 2-stage vaccination of all age group with the aim of ensuring responses to all 3 LIV components is, certainly, a LIV disadvantage. In case of IIV, the 2-stage vaccination is needed only for persons who were not ill with influenza. The intranasal LIV administration has, from the practical and psychological standpoints, an advantage before the IIV administration by syringe. The ability of LIV to protect from the drift influenza-virus variations could be its advantage before IIV; still, more research is needed to verify it. Transplantable cell lines meeting the WHO requirements could be an optimal substrate for the production of LIV and IIV. Children are the optimal age group for influenza prevention by cold-adapted LIV, whereas, IIV fits better for vaccination of adults and elderly persons.

  10. Immunity and protection by live attenuated HIV/SIV vaccines

    PubMed Central

    Wodarz, Dominik

    2008-01-01

    Live attenuated virus vaccines have shown the greatest potential to protect against simian immunodeficiency virus (SIV) infection, a model for human immunodeficiency virus (HIV). Immunity against the vaccine virus is thought to mediate protection. However, it is shown computationally that the opposite might be true. According to the model, the initial growth of the challenge strain, its peak load, and its potential to be pathogenic is higher if immunity against the vaccine virus is stronger. This is because the initial growth of the challenge strain is mainly determined by virus competition rather than immune suppression. The stronger the immunity against the vaccine strain, the weaker its competitive ability relative to the challenge strain, and the lower the level of protection. If the vaccine virus does protect the host against a challenge, it is because the competitive interactions between the viruses inhibit the initial growth of the challenge strain. According to these arguments, an inverse correlation between the level of attenuation and the level of protection is expected, and this has indeed been observed in experimental data. PMID:18586297

  11. Correlates of protection induced by live Aro- Salmonella typhimurium vaccines in the murine typhoid model.

    PubMed Central

    Harrison, J A; Villarreal-Ramos, B; Mastroeni, P; Demarco de Hormaeche, R; Hormaeche, C E

    1997-01-01

    Live attenuated salmonella vaccines generally confer better protection than killed vaccines. The immune responses in BALB/c mice elicited by immunization with a live attenuated Aro Salmonella typhimurium vaccine given orally, intravenously or subcutaneously were compared with those elicited by killed whole-cell vaccines (acetone or heat-treated) given subcutaneously. Live vaccines given by all routes elicited higher interleukin-2 (IL-2) and interferon-gamma (IFN-gamma) responses in spleen cells against an alkali-treated whole-cell salmonella lysate than did killed vaccines. Live and killed vaccines elicited high total antibody levels to smooth lipopolysaccharide (LPS) (enzyme-linked immunosorbent assay), but all live vaccine regimes elicited higher IgG2a, suggesting a Th1 response. Oral and intravenous vaccination with live organisms elicited IgA against smooth LPS which subcutaneous vaccination with live or killed salmonellae failed to evoke. Western blots using rough whole-cell lysates showed that all vaccines elicited a varied anti-protein response; however, all groups immunized with live organisms recognized three unidentified bands of MW 52,000, 46,000 and 18,000 which were consistently absent in groups immunized with killed organisms. The results indicate that immunization with live aroA salmonellae elicited a Th1 type of response, including bystander T-cell help to LPS, and a response to proteins not seen in mice that received killed vaccines. Images Figure 6 PMID:9176117

  12. Protective effects of recombinant Brucella abortus Omp28 against infection with a virulent strain of Brucella abortus 544 in mice.

    PubMed

    Lim, Jeong Ju; Kim, Dong Hyeok; Lee, Jin Ju; Kim, Dae Geun; Min, Wongi; Lee, Hu Jang; Rhee, Man Hee; Kim, Suk

    2012-09-01

    The outer membrane proteins (OMPs) of Brucella (B.) abortus have been extensively studied, but their immunogenicity and protective ability against B. abortus infection are still unclear. In the present study, B. abortus Omp28, a group 3 antigen, was amplified by PCR and cloned into a maltose fusion protein expression system. Recombinant Omp28 (rOmp28) was expressed in Escherichia coli and was then purified. Immunogenicity of rOmp28 was confirmed by Western blot analysis with Brucella-positive mouse serum. Furthermore, humoral- or cell-mediated immune responses measured by the production of IgG1 or IgG2a in rOmp28-immunized mice and the ability of rOmp28 immunization to protect against B. abortus infection were evaluated in a mouse model. In the immunogenicity analysis, the mean titers of IgG1 and IgG2a produced by rOmp28-immunized mice were 20-fold higher than those of PBS-treated mice throughout the entire experimental period. Furthermore, spleen proliferation and bacterial burden in the spleen of rOmp28-immunized mice were approximately 1.5-fold lower than those of PBS-treated mice when challenged with virulent B. abortus. These findings suggest that rOmp28 from B. abortus is a good candidate for manufacturing an effective subunit vaccine against B. abortus infection in animals.

  13. Development of a live attenuated antigenic marker classical swine fever vaccine

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Classical Swine Fever, caused by Classical Swine Fever Virus (CSFV), is a highly contagious disease affecting swine worldwide. The two main strategies for disease control are prophylactic vaccination and non-vaccination “stamping out” policies. In a vaccination-to-live strategy, marker vaccines coul...

  14. Seasonal Effectiveness of Live Attenuated and Inactivated Influenza Vaccine

    PubMed Central

    Flannery, Brendan; Thompson, Mark G.; Gaglani, Manjusha; Jackson, Michael L.; Monto, Arnold S.; Nowalk, Mary Patricia; Talbot, H. Keipp; Treanor, John J.; Belongia, Edward A.; Murthy, Kempapura; Jackson, Lisa A.; Petrie, Joshua G.; Zimmerman, Richard K.; Griffin, Marie R.; McLean, Huong Q.; Fry, Alicia M.

    2016-01-01

    BACKGROUND: Few observational studies have evaluated the relative effectiveness of live attenuated (LAIV) and inactivated (IIV) influenza vaccines against medically attended laboratory-confirmed influenza. METHODS: We analyzed US Influenza Vaccine Effectiveness Network data from participants aged 2 to 17 years during 4 seasons (2010–2011 through 2013–2014) to compare relative effectiveness of LAIV and IIV against influenza-associated illness. Vaccine receipt was confirmed via provider/electronic medical records or immunization registry. We calculated the ratio (odds) of influenza-positive to influenza-negative participants among those age-appropriately vaccinated with either LAIV or IIV for the corresponding season. We examined relative effectiveness of LAIV and IIV by using adjusted odds ratios (ORs) and 95% confidence intervals (CIs) from logistic regression. RESULTS: Of 6819 participants aged 2 to 17 years, 2703 were age-appropriately vaccinated with LAIV (n = 637) or IIV (n = 2066). Odds of influenza were similar for LAIV and IIV recipients during 3 seasons (2010–2011 through 2012–2013). In 2013–2014, odds of influenza were significantly higher among LAIV recipients compared with IIV recipients 2 to 8 years old (OR 5.36; 95% CI, 2.37 to 12.13). Participants vaccinated with LAIV or IIV had similar odds of illness associated with influenza A/H3N2 or B. LAIV recipients had greater odds of illness due to influenza A/H1N1pdm09 in 2010–2011 and 2013–2014. CONCLUSIONS: We observed lower effectiveness of LAIV compared with IIV against influenza A/H1N1pdm09 but not A(H3N2) or B among children and adolescents, suggesting poor performance related to the LAIV A/H1N1pdm09 viral construct. PMID:26738884

  15. 76 FR 3075 - Availability of an Environmental Assessment for Field Testing Feline Leukemia Vaccine, Live...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-01-19

    ... Feline Leukemia Vaccine, Live Canarypox Vector AGENCY: Animal and Plant Health Inspection Service, USDA... testing, and then to field test, an unlicensed Feline Leukemia Vaccine, Live Canarypox Vector. The... field testing of this vaccine, examines the potential effects that field testing this veterinary...

  16. Development of live attenuated influenza vaccines against pandemic influenza strains.

    PubMed

    Coelingh, Kathleen L; Luke, Catherine J; Jin, Hong; Talaat, Kawsar R

    2014-07-01

    Avian and animal influenza viruses can sporadically transmit to humans, causing outbreaks of varying severity. In some cases, further human-to-human virus transmission does not occur, and the outbreak in humans is limited. In other cases, sustained human-to-human transmission occurs, resulting in worldwide influenza pandemics. Preparation for future pandemics is an important global public health goal. A key objective of preparedness is to gain an understanding of how to design, test, and manufacture effective vaccines that could be stockpiled for use in a pandemic. This review summarizes results of an ongoing collaboration to produce, characterize, and clinically test a library of live attenuated influenza vaccine strains (based on Ann Arbor attenuated Type A strain) containing protective antigens from influenza viruses considered to be of high pandemic potential.

  17. Brucella abortus in captive bison. I. Serology, bacteriology, pathogenesis, and transmission to cattle.

    PubMed

    Davis, D S; Templeton, J W; Ficht, T A; Williams, J D; Kopec, J D; Adams, L G

    1990-07-01

    Two groups of six, non-brucellosis vaccinated, brucellosis seronegative pregnant American bison (Bison bison) were individually challenged with 1 x 10(7) colony forming units (CFU) of Brucella abortus strain 2308. Three days after challenge, each bison group was placed in a common paddock with six non-vaccinated, brucellosis susceptible, pregnant domestic heifers. In a parallel study, two groups of six susceptible, pregnant cattle were simultaneously challenged with the identical dose as the bison and each group was placed with six susceptible cattle in order to compare bison to cattle transmission to that observed in cattle to cattle transmission. Blood samples were collected from bison and cattle weekly for at least 1 mo prior to exposure to B. abortus and for 180 days post-exposure (PE). Sera from the bison and cattle were evaluated by the Card, rivanol precipitation, standard plate agglutination, standard tube agglutination, cold complement fixation tube, warm complement fixation tube, buffered acidified plate antigen, rapid screening, bovine conjugated enzyme linked immunosorbent assay, bison or bovine conjugated enzyme linked immunosorbent assay, and the hemolysis-in-gel techniques for the presence of antibodies to Brucella spp. At the termination of pregnancy by abortion or birth of a live-calf, quarter milk samples, vaginal swabs, and placenta were collected from the dam. Rectal swabs were collected from live calves, and mediastinal lymph nodes, abomasal contents and lung were taken at necropsy from aborted fetuses for culture of Brucella spp. These tissues and swabs were cultured on restrictive media for the isolation and identification of Brucella spp. Pathogenesis of brucellosis in bison was studied in an additional group of six pregnant bison which were challenged with 1 x 10(7) CFU of B. abortus strain 2308. One animal was euthanatized each week PE. Tissues were collected at necropsy and later examined bacteriologically and histologically. Lesions of

  18. Ontology representation and analysis of vaccine formulation and administration and their effects on vaccine immune responses

    PubMed Central

    2012-01-01

    Background A vaccine is a processed material that if administered, is able to stimulate an adaptive immune response to prevent or ameliorate a disease. A vaccination process may protect the host against subsequent exposure to an infectious agent and result in reduced disease or total prevention of the disease. Vaccine formulation and administration methods may affect vaccine safety and efficacy significantly. Results In this report, the detailed classification and definitions of vaccine components and vaccine administration processes are represented using OWL within the framework of the Vaccine Ontology (VO). Different use cases demonstrate how different vaccine formulations and routes of vaccine administration affect the protection efficacy, general immune responses, and adverse events following vaccination. For example, vaccinations of mice with Brucella abortus vaccine strain RB51 using intraperitoneal or intranasal administration resulted in different protection levels. As shown in the vaccine adverse event data provided by US FDA, live attenuated and nonliving vaccines are usually administered in different routes and have different local and systematic adverse effect manifestations. Conclusions Vaccine formulation and administration route can independently or collaboratively affect host response outcomes (positive protective immunity or adverse events) after vaccination. Ontological representation of different vaccine and vaccination factors in these two areas allows better understanding and analysis of the causal effects between different factors and immune responses. PMID:23256535

  19. Development of a human live attenuated West Nile infectious DNA vaccine: conceptual design of the vaccine candidate.

    PubMed

    Yamshchikov, Vladimir

    2015-10-01

    West Nile virus has become an important epidemiological problem attracting significant attention of health authorities, mass media, and the public. Although there are promising advancements toward addressing the vaccine need, the perspectives of the commercial availability of the vaccine remain uncertain. To a large extent this is due to lack of a sustained interest for further commercial development of the vaccines already undergoing the preclinical and clinical development, and a predicted insignificant cost effectiveness of mass vaccination. There is a need for a safe, efficacious and cost effective vaccine, which can improve the feasibility of a targeted vaccination program. In the present report, we summarize the background, the rationale, and the choice of the development pathway that we selected for the design of a live attenuated human West Nile vaccine in a novel infectious DNA format.

  20. Genetic strain modification of a live rabies virus vaccine widely used in Europe for wildlife oral vaccination.

    PubMed

    Cliquet, Florence; Robardet, Emmanuelle; Picard Meyer, Evelyne

    2013-10-01

    In Europe, the main reservoir and vector of rabies has been the red fox (Vulpes vulpes). Oral immunization of foxes with live vaccines, using attenuated rabies strains (SAD B19, SAD Bern), apathogenic mutants of an attenuated strain (SAG2) and the vaccinia-rabies glycoprotein recombinant virus vaccine (V-RG), has been shown to be the most effective method for the control and elimination of rabies. Among all vaccines currently used for wildlife oral vaccination, one vaccine (marketed as SAD Bern strain) has been widely used in Europe since 1992 with the distribution of 17million of baits in 2011. Because of the potential environmental safety risk of a live virus which could revert to virulence, the full genome sequencing of this vaccine was undertaken and the sequence was characterized and compared with those of referenced rabies viruses. The vaccine showed higher similarity to the strains belonging to the SAD B19 vaccine virus strains than to the SAD Bern vaccines. This study is the first one reporting on virus strain identity changes in this attenuated vaccine.

  1. Live Attenuated and Inactivated Influenza Vaccines in Children

    PubMed Central

    Ilyushina, Natalia A.; Haynes, Brenda C.; Hoen, Anne G.; Khalenkov, Alexey M.; Housman, Molly L.; Brown, Eric P.; Ackerman, Margaret E.; Treanor, John J.; Luke, Catherine J.; Subbarao, Kanta; Wright, Peter F.

    2015-01-01

    Background. Live attenuated influenza vaccine (LAIV) and inactivated influenza vaccine (IIV) are available for children. Local and systemic immunity induced by LAIV followed a month later by LAIV and IIV followed by LAIV were investigated with virus recovery after LAIV doses as surrogates for protection against influenza on natural exposure. Methods. Fifteen children received IIV followed by LAIV, 13 an initial dose of LAIV, and 11 a second dose of LAIV. The studies were done during autumn 2009 and autumn 2010 with the same seasonal vaccine (A/California/07/09 [H1N1], A/Perth/16/09 [H3N2], B/Brisbane/60/08). Results. Twenty-eight of 39 possible influenza viral strains were recovered after the initial dose of LAIV. When LAIV followed IIV, 21 of 45 viral strains were identified. When compared to primary LAIV infection, the decreased frequency of shedding with the IIV-LAIV schedule was significant (P = .023). With LAIV-LAIV, the fewest viral strains were recovered (3/33)—numbers significantly lower (P < .001) than shedding after initial LAIV and after IIV-LAIV (P < .001). Serum hemagglutination inhibition antibody responses were more frequent after IIV than LAIV (P = .02). In contrast, more mucosal immunoglobulin A responses were seen with LAIV. Conclusions. LAIV priming induces greater inhibition of virus recovery on LAIV challenge than IIV priming. The correlate(s) of protection are the subject of ongoing analysis. Clinical Trials Registration. NCT01246999. PMID:25165161

  2. Reassortant rotaviruses as potential live rotavirus vaccine candidates.

    PubMed Central

    Midthun, K; Greenberg, H B; Hoshino, Y; Kapikian, A Z; Wyatt, R G; Chanock, R M

    1985-01-01

    A series of reassortants was isolated from coinfection of cell cultures with a wild-type animal rotavirus and a "noncultivatable" human rotavirus. Wild-type bovine rotavirus (UK strain) was reassorted with human rotavirus strains D, DS-1, and P; wild-type rhesus rotavirus was reassorted with human rotavirus strains D and DS-1. The D, DS-1, and P strains represent human rotavirus serotypes 1, 2, and 3, respectively. Monospecific antiserum (to bovine rotavirus, NCDV strain) or a set of monoclonal antibodies to the major outer capsid neutralization glycoprotein, VP7 (of the rhesus rotavirus), was used to select for reassortants with human rotavirus neutralization specificity. This selection technique yielded many reassortants which received only the gene segment coding for the major neutralization protein from the human rotavirus parent, whereas the remaining genes were derived from the animal rotavirus parent. Single human rotavirus gene substitution reassortants of this sort represent potential live vaccine strains. Images PMID:2983101

  3. The efficacy of Mycoplasma gallisepticum K-strain live vaccine in broiler and layer chickens.

    PubMed

    Ferguson-Noel, N M; Williams, S M

    2015-01-01

    The efficacy of a live Mycoplasma gallisepticum (MG) vaccine candidate (K-strain) was compared to commercially available vaccines in broiler-type chickens (Trial 1) and layer-type chickens (Trial 2). In Trial 1, three-week-old broiler-type chickens were vaccinated via aerosol with K-strain or an F-strain vaccine. The vaccinated chickens and 10 non-vaccinated controls were subsequently challenged with virulent R-strain via aerosol at six weeks post vaccination; both K-strain and F-strain vaccination resulted in significant protection from air sac and tracheal lesions, as well as R-strain colonization (P ≤ 0.05). In Trial 2, commercial layer-type chickens were vaccinated with ts-11 (via eye drop) or K-strain (via aerosol) at 12 weeks of age. At 25 weeks of age these birds were challenged with R-strain via aerosol. The ts-11 and K-strain vaccinated groups both had significantly lower air sac lesion scores and a lower prevalence of ovarian regression after challenge as compared to non-vaccinated chickens (P ≤ 0.05). K-strain vaccination also prevented significant tracheal lesions and R-strain colonization (P ≤ 0.05). K-strain shows great potential as a highly efficacious live MG vaccine in broiler and layer-type chickens for protection of the respiratory and reproductive systems as well as prevention of infection with field strains.

  4. Shedding of live Eimeria vaccine progeny is delayed in chicks with delayed access to feed after vaccination.

    PubMed

    Price, Kayla R; Freeman, Megan; Van-Heerden, Kobus; Barta, John R

    2015-03-15

    Hatching, processing and transportation result in inevitable delays before chicks are placed into brooding and receive their first feed and drinking water after hatching. To determine if delayed access to feed for different durations following live Eimeria vaccination affected initial shedding of vaccine progeny, replacement layer chicks (480, Lohmann-LSL Lite) aged approximately 6h after hatch were administered a commercial live Eimeria vaccine. Vaccinated chicks were divided randomly into groups and were provided access to feed immediately (0 h) or after a delay of 6, 12, or 24 h (4 treatments × 6 replicates per treatment × 20 pullets per replicate). All pullets were provided drinking water immediately following vaccination. Fecal oocysts shed per gram of feces for each cage replicate was determined daily from 4 to 9 days post inoculation. Chicks provided feed immediately had peak oocyst shedding at 5 days post-inoculation but delayed access to feed for 24h was associated with a 2 days delay in peak oocyst shedding to 7 days post-inoculation. Chicks with delays in access to feed of intermediate duration (i.e. 6 or 12h) had peak oocyst shedding at 6 days post-inoculation. Overall oocyst shedding was not affected. Live Eimeria vaccination success may be measured by evaluating initial shedding of oocysts at some pre-established time after vaccine application, usually by a single fecal collection conducted at 5, 6 or 7 days post-inoculation. Recognizing that withholding feed following live Eimeria vaccination shifts the time of the resultant peak oocyst shedding complicates the assessment of vaccine application; if delayed access to feed is not taken into account, it is possible that false conclusions could be drawn regarding the relative success of vaccine administration.

  5. Vaccination of full-sib channel catfish families against enteric septicemia of catfish with an oral live attenuated Edwardsiella ictaluri vaccine

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The study evaluated the efficacy of an oral live-attenuated Edwardsiella ictaluri vaccine against enteric septicemia of catfish in 20 full-sib fingerling channel catfish families. Each family was split into vaccinated and non-vaccinated groups. The vaccine was delivered orally by feeding fish diet...

  6. Deletion of the BCSP31 gene of Brucella abortus by replacement.

    PubMed Central

    Halling, S M; Detilleux, P G; Tatum, F M; Judge, B A; Mayfield, J E

    1991-01-01

    The 31-kDa salt-extractable immunogenic protein, BCSP31, was deleted from several Brucella abortus strains by replacement with a marker gene encoding resistance to the antibiotics kanamycin and neomycin. The BCSP31 gene replacement plasmids, constructed with ColE1-derived vectors, were introduced by electroporation into B. abortus strain 19 (S19), into a rough variant of B. abortus S19, and into B. abortus S2308, and antibiotic-resistant transformants were isolated. B. abortus S19 is an attenuated strain used as a vaccine for prevention of bovine brucellosis in the United States, and B. abortus S2308 is a commonly used challenge strain. The antibiotic-resistant isolates were all obtained by recombination; none were spontaneous mutants. Loss of the gene encoding BCSP31 and presence of the marker gene were confirmed by Southern analysis. Vector sequences were either absent or linked to the genome, indicating that ColE1-derived plasmids are not maintained in B. abortus. Survival of B. abortus mutant strains in the macrophagelike cell line J774 and in HeLa cells was examined and shown to be indistinguishable from that of the parental strain. Images PMID:1937745

  7. Evaluation of reproductive protection against bovine viral diarrhea virus and bovine herpesvirus-1 afforded by annual revaccination with modified-live viral or combination modified-live/killed viral vaccines after primary vaccination with modified-live viral vaccine.

    PubMed

    Walz, Paul H; Givens, M Daniel; Rodning, Soren P; Riddell, Kay P; Brodersen, Bruce W; Scruggs, Daniel; Short, Thomas; Grotelueschen, Dale

    2017-02-15

    The objective of this study was to compare reproductive protection in cattle against bovine viral diarrhea virus (BVDV) and bovine herpesvirus 1 (BoHV-1) provided by annual revaccination with multivalent modified-live viral (MLV) vaccine or multivalent combination viral (CV) vaccine containing temperature-sensitive modified-live BoHV-1 and killed BVDV when MLV vaccines were given pre-breeding to nulliparous heifers. Seventy-five beef heifers were allocated into treatment groups A (n=30; two MLV doses pre-breeding, annual revaccination with MLV vaccine), B (n=30; two MLV doses pre-breeding, annual revaccination with CV vaccine) and C (n=15; saline in lieu of vaccine). Heifers were administered treatments on days 0 (weaning), 183 (pre-breeding), 366 (first gestation), and 738 (second gestation). After first calving, primiparous cows were bred, with pregnancy assessment on day 715. At that time, 24 group A heifers (23 pregnancies), 23 group B heifers (22 pregnancies), and 15 group C heifers (15 pregnancies) were commingled with six persistently infected (PI) cattle for 16days. Ninety-nine days after PI removal, cows were intravenously inoculated with BoHV-1. All fetuses and live offspring were assessed for BVDV and BoHV-1. Abortions occurred in 3/23 group A cows, 1/22 group B cows, and 11/15 group C cows. Fetal infection with BVDV or BoHV-1 occurred in 4/23 group A offspring, 0/22 group B offspring, and 15/15 group C offspring. This research demonstrates efficacy of administering two pre-breeding doses of MLV vaccine with annual revaccination using CV vaccine to prevent fetal loss due to exposure to BVDV and BoHV-1.

  8. Intermediate rough Brucella abortus S19Δper mutant is DIVA enable, safe to pregnant guinea pigs and confers protection to mice.

    PubMed

    Lalsiamthara, Jonathan; Gogia, Neha; Goswami, Tapas K; Singh, R K; Chaudhuri, Pallab

    2015-05-21

    Brucella abortus S19 is a smooth strain used as live vaccine against bovine brucellosis. Smooth lipopolysaccharide (LPS) is responsible for its residual virulence and serological interference. Rough mutants defective of LPS are more attenuated but confers lower level of protection. We describe a modified B. abortus S19 strain, named as S19Δper, which exhibits intermediate rough phenotype with residual O-polysaccharide (OPS). Deletion of perosamine synthetase gene resulted in substantial attenuation of S19Δper mutant without affecting immunogenic properties. It mounted strong immune response in Swiss albino mice and conferred protection similar to S19 vaccine. Immunized mice produced higher levels of IFN-γ, IgG2a and thus has immune response inclined towards Th1 cell mediated immunity. Sera from immunized animals did not show agglutination reaction with RBPT antigen and thus could serve as DIVA (Differentiating Infected from Vaccinated Animals) vaccine. S19Δper mutant displayed more susceptibility to serum complement mediated killing and sensitivity to polymyxin B. Pregnant guinea pigs injected with S19Δper mutant completed full term of pregnancy and did not cause abortion, still birth or birth of weak offspring. S19Δper mutant with intermediate rough phenotype displayed remarkable resemblance to S19 vaccine strain with improved properties of safety, immunogenicity and DIVA capability for control of bovine brucellosis.

  9. Efficacy and effectiveness of live attenuated influenza vaccine in school-age children.

    PubMed

    Coelingh, Kathleen; Olajide, Ifedapo Rosemary; MacDonald, Peter; Yogev, Ram

    2015-01-01

    Evidence of high efficacy of live attenuated influenza vaccine (LAIV) from randomized controlled trials is strong for children 2-6 years of age, but fewer data exist for older school-age children. We reviewed the published data on efficacy and effectiveness of LAIV in children ≥5 years. QUOSA (Elsevier database) was searched for articles published from January 1990 to June 2014 that included 'FluMist', 'LAIV', 'CAIV', 'cold adapted influenza vaccine', 'live attenuated influenza vaccine', 'live attenuated cold adapted' or 'flu mist'. Studies evaluated included randomized controlled trials, effectiveness and indirect protection studies. This review demonstrates that LAIV has considerable efficacy and effectiveness in school-age children.

  10. Serological response of foals to polyvalent and monovalent live-attenuated African horse sickness virus vaccines.

    PubMed

    Crafford, J E; Lourens, C W; Smit, T K; Gardner, I A; MacLachlan, N J; Guthrie, A J

    2014-06-17

    African horse sickness (AHS) is typically a highly fatal disease in susceptible horses and vaccination is currently used to prevent the occurrence of disease in endemic areas. Similarly, vaccination has been central to the control of incursions of African horse sickness virus (AHSV) into previously unaffected areas and will likely play a significant role in any future incursions. Horses in the AHSV-infected area in South Africa are vaccinated annually with a live-attenuated (modified-live virus [MLV]) vaccine, which includes a cocktail of serotypes 1, 3, 4 (bottle 1) and 2, 6-8 (bottle 2) delivered in two separate doses at least 21 days apart. In this study, the neutralising antibody response of foals immunized with this polyvalent MLV AHSV vaccine was evaluated and compared to the response elicited to monovalent MLV AHSV serotypes. Naïve foals were immunized with either the polyvalent MLV AHSV vaccine, or a combination of monovalent MLV vaccines containing individual AHSV serotypes 1, 4, 7 or 8. There was a marked and consistent difference in the immunogenicity of individual virus serotypes contained in the MLV vaccines. Specifically, foals most consistently seroconverted to AHSV-1 and responses to other serotypes were highly variable, and often weak or not detected. The serotype-specific responses of foals given the monovalent MLV vaccines were similar to those of foals given the polyvalent MLV preparation suggesting that there is no obvious enhanced immune response through the administration of a monovalent vaccine as opposed to the polyvalent vaccine.

  11. Mutant Brucella abortus membrane fusogenic protein induces protection against challenge infection in mice.

    PubMed

    de Souza Filho, Job Alves; de Paulo Martins, Vicente; Campos, Priscila Carneiro; Alves-Silva, Juliana; Santos, Nathalia V; de Oliveira, Fernanda Souza; Menezes, Gustavo B; Azevedo, Vasco; Cravero, Silvio Lorenzo; Oliveira, Sergio Costa

    2015-04-01

    Brucella species can cause brucellosis, a zoonotic disease that causes serious livestock economic losses and represents a public health threat. The mechanism of virulence of Brucella spp. is not yet fully understood. Therefore, it is crucial to identify new molecules that serve as virulence factors to better understand this host-pathogen interplay. Here, we evaluated the role of the Brucella membrane fusogenic protein (Mfp) and outer membrane protein 19 (Omp19) in bacterial pathogenesis. In this study, we showed that B. abortus Δmfp::kan and Δomp19::kan deletion mutant strains have reduced persistence in vivo in C57BL/6 and interferon regulatory factor 1 (IRF-1) knockout (KO) mice. Additionally, 24 h after macrophage infection with a Δmfp::kan or Δomp19::kan strain expressing green fluorescent protein (GFP) approximately 80% or 65% of Brucella-containing vacuoles (BCVs) retained the late endosomal/lysosomal marker LAMP-1, respectively, whereas around 60% of BCVs containing wild-type S2308 were found in LAMP-1-negative compartments. B. abortus Δomp19::kan was attenuated in vivo but had a residual virulence in C57BL/6 and IRF-1 KO mice, whereas the Δmfp::kan strain had a lower virulence in these same mouse models. Furthermore, Δmfp::kan and Δomp19::kan strains were used as live vaccines. Challenge experiments revealed that in C57BL/6 and IRF-1 KO mice, the Δmfp::kan strain induced greater protection than the vaccine RB51 and protection similar that of vaccine S19. However, a Δomp19::kan strain induced protection similar to that of RB51. Thus, these results demonstrate that Brucella Mfp and Omp19 are critical for full bacterial virulence and that the Δmfp::kan mutant may serve as a potential vaccine candidate in future studies.

  12. Gene-deleted live-attenuated Trypanosoma cruzi parasites as vaccines to protect against Chagas disease.

    PubMed

    Sánchez-Valdéz, Fernando J; Pérez Brandán, Cecilia; Ferreira, Arturo; Basombrío, Miguel Ángel

    2015-05-01

    Chagas disease is a neglected tropical disease caused by the protozoan parasite Trypanosoma cruzi. This illness is now becoming global, mainly due to congenital transmission, and so far, there are no prophylactic or therapeutic vaccines available to either prevent or treat Chagas disease. Therefore, different approaches aimed at identifying new protective immunogens are urgently needed. Live vaccines are likely to be more efficient in inducing protection, but safety issues linked with their use have been raised. The development of improved protozoan genetic manipulation tools and genomic and biological information has helped to increase the safety of live vaccines. These advances have generated a renewed interest in the use of genetically attenuated parasites as vaccines against Chagas disease. This review discusses the protective capacity of genetically attenuated parasite vaccines and the challenges and perspectives for the development of an effective whole-parasite Chagas disease vaccine.

  13. Current efforts and future prospects in the development of live mycobacteria as vaccines.

    PubMed

    Ng, Tony W; Saavedra-Ávila, Noemí A; Kennedy, Steven C; Carreño, Leandro J; Porcelli, Steven A

    2015-01-01

    The development of more effective vaccines against Mycobacterium tuberculosis (Mtb) remains a major goal in the effort to reduce the enormous global burden of disease caused by this pathogen. Whole-cell vaccines based on live mycobacteria with attenuated virulence represent an appealing approach, providing broad antigen exposure and intrinsic adjuvant properties to prime durable immune responses. However, designing vaccine strains with an optimal balance between attenuation and immunogenicity has proven to be extremely challenging. Recent basic and clinical research efforts have broadened our understanding of Mtb pathogenesis and created numerous new vaccine candidates that have been designed to overcome different aspects of immune evasion by Mtb. In this review, we provide an overview of the current efforts to create improved vaccines against tuberculosis based on modifications of live attenuated mycobacteria. In addition, we discuss the use of such vaccine strains as vectors for stimulating protective immunity against other infectious diseases and cancers.

  14. A review of immunogenicity and tolerability of live attenuated Hepatitis A vaccine in children

    PubMed Central

    Rao, Sameer; Mao, J. S.; Motlekar, Salman; Fangcheng, Zhuang; Kadhe, Ganesh

    2016-01-01

    ABSTRACT Changing epidemiology of Hepatitis A virus (HAV) has led to an increased susceptibility of adolescents and adults to the infection. Vaccination can remarkably reduce the incidence and associated morbidity of HAV infection. This review is focused on the safety and efficacy of H2 strain derived live attenuated Hepatitis A vaccine. We found the vaccine to be highly immunogenic with minimal or negligible safety issues. Moreover, a single dose of live attenuated vaccine persists a long term immune response and can be a preferred option for developing countries. In 2014, Indian Academy of Paediatrics (IAP) also updated their recommendations for H2 vaccine as a single dose as against the previous 2 dose schedule. A focused approach to include the vaccine in national immunization program should be explored. PMID:27532370

  15. Using recombinant DNA technology for the development of live-attenuated dengue vaccines.

    PubMed

    Lee, Hsiang-Chi; Butler, Michael; Wu, Suh-Chin

    2012-07-15

    Dramatic increases in dengue (DEN) incidence and disease severity have been reported, in great part due to the geographic expansion of Aedes aegypti and Aedes albopictus mosquitoes. One result is the expanded co-circulation of all dengue 1-4 serotype viruses (DENV) in urban areas worldwide, especially in South and South-East Asia, and South America. DEN disease severity ranges from asymptomatic infections to febrile dengue fevers (DF) to life-threatening dengue hemorrhagic fever (DHF) and dengue shock syndrome (DSS). There is an urgent need for a safe and effective tetravalent DEN vaccine. Several live attenuated, tetravalent DEN vaccine candidates have been generated by recombinant DNA technology; these candidates are capable of providing immunity to all four DENV serotypes. In this paper we review (a) recombinant live-attenuated DEN vaccine candidates in terms of deletion, antigen chimerization, and the introduction of adaptive mutations; (b) strategies for improving tetravalent vaccine attenuation; and (c) live-attenuated DENV vaccine development.

  16. Vaccine supply chains need to be better funded and strengthened, or lives will be at risk.

    PubMed

    Kaufmann, Judith R; Miller, Roger; Cheyne, James

    2011-06-01

    In the next decade, at least twelve additional vaccines that target such diseases as typhoid, malaria, and dengue will become available to lower- and middle-income countries. These vaccines must travel along what are called supply chains, which include all personnel, systems, equipment, and activities involved in ensuring that vaccines are effectively delivered from the point of production to the people who need them. But for various reasons, supply chains are already strained in many developing countries, and the potential inability to distribute new vaccines will place lives at risk. Among the many steps needed to strengthen the global vaccine supply chain, we suggest that the international community pursue improved coordination between organizations that donate and ship vaccines and the host-country officials who receive and distribute the vaccines, as well as better training for supply-chain managers.

  17. Characterization of an intracellular ATP assay for evaluating the viability of live attenuated mycobacterial vaccine preparations.

    PubMed

    Kolibab, Kristopher; Derrick, Steven C; Jacobs, William R; Morris, Sheldon L

    2012-09-01

    The viability of BCG vaccine has traditionally been monitored using a colony-forming unit (CFU) assay. Despite its widespread use, results from the CFU assay can be highly variable because of the characteristic clumping of mycobacteria, their requirement for complex growth media, and the three week incubation period needed to cultivate slow-growing mycobacteria. In this study, we evaluated whether an ATP luminescence assay (which measures intracellular ATP content) could be used to rapidly estimate the viability of lyophilized and/or frozen preparations of six different BCG vaccine preparations - Danish, Tokyo, Russia, Brazil, Tice, and Pasteur - and two live attenuated mycobacterial vaccine candidates - a ΔlysAΔpanCD M. tuberculosis strain and a ΔmmaA4 BCG vaccine mutant. For every vaccine tested, a significant correlation was observed between intracellular ATP concentrations and the number of viable attenuated bacilli. However, the extractable intracellular ATP levels detected per cell among the different live vaccines varied suggesting that validated ATP luminescence assays with specific appropriate standards must be developed for each individual live attenuated vaccine preparation. Overall, these data indicate that the ATP luminescence assay is a rapid, sensitive, and reliable alternative method for quantifying the viability of varying live attenuated mycobacterial vaccine preparations.

  18. Postpartum live virus vaccination: lessons from veterinary medicine.

    PubMed

    Yazbak, F Edward; Diodati, Catherine J M

    2002-09-01

    Pregnant rubella-susceptible women are often revaccinated during the postpartum period with the Measles, Mumps, and Rubella vaccine (MMR). It is known that the rubella virus from vaccine is secreted in breast milk and persists in the nose and throat for up to 28 days but it is not known whether the measles and mumps viruses are similarly secreted. It is probable the measles virus from vaccine is.

  19. Factors affecting the efficacy of live poliovirus vaccine in warm climates

    PubMed Central

    Dömök, I.; Balayan, M. S.; Fayinka, O. A.; Škrtić, N.; Soneji, A. D.; Harland, P. S. E. G.

    1974-01-01

    A virologically controlled field trial was conducted with live monovalent type 1 poliovirus vaccine in children aged 3-30 months living in a rural area of Uganda, in an attempt to find out the reason for the poor efficacy of such vaccine often observed in countries with a warm climate. Groups of breast-fed and of artificially fed infants received the vaccine orally, either alone or mixed with horse serum prepared against partly purified human gamma-globulin. Irrespective of the diet, the “take rate”—measured by the rates of vaccine virus excretion and of antibody conversion—was found to be poor when the vaccine was given alone but satisfactory when it was given together with the horse antiserum. However, the extent and duration of vaccine virus multiplication in the intestinal tract proved to be limited and the mean antibody level elicited by the vaccination, irrespective of the schedule of vaccine administration, was low. These results, besides indicating that breast-feeding does not influence the efficacy of vaccination in the age groups studied, revealed the presence of an inhibitor in the alimentary tract. This inhibitor acts against the multiplication of vaccine virus, which may be blocked by antibodies in the horse antiserum for a limited period at the time of vaccination. Interference between the enteroviruses and the vaccine strain was also found to be responsible for decreasing the efficacy of vaccination, though its role was secondary to that of the inhibitor. Revaccination experiments showed that the effects of both inhibitor and interference may be overcome by repeated administration of the vaccine. PMID:4142936

  20. Spray application of live attenuated F Strain-derived Mycoplasma gallisepticum vaccines

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Live attenuated vaccines (LAVs) are commonly utilized to protect commercial table egg producers from economic losses associated with challenges by the respiratory pathogen Mycoplasma gallisepticum (MG). Currently there are four MG LAVs commercially available within the United States. Consistent am...

  1. Live attenuated varicella-zoster vaccine in hematopoietic stem cell transplantation recipients.

    PubMed

    Issa, Nicolas C; Marty, Francisco M; Leblebjian, Houry; Galar, Alicia; Shea, Margaret M; Antin, Joseph H; Soiffer, Robert J; Baden, Lindsey R

    2014-02-01

    Hematopoietic stem cell transplantation (HSCT) recipients are at risk for varicella-zoster virus (VZV) reactivation. Vaccination may help restore VZV immunity; however, the available live attenuated VZV vaccine (Zostavax) is contraindicated in immunocompromised hosts. We report our experience with using a single dose of VZV vaccine in 110 adult autologous and allogeneic HSCT recipients who were about 2 years after transplantation, free of graft-versus-host disease, and not receiving immunosuppression. One hundred eight vaccine recipients (98.2%) had no clinically apparent adverse events with a median follow-up period of 9.5 months (interquartile range, 6 to 16; range, 2 to 28). Two vaccine recipients (1.8%) developed a skin rash (one zoster-like rash with associated pain, one varicella-like) within 42 days post-vaccination that resolved with antiviral therapy. We could not confirm if these rashes were due to vaccine (Oka) or wild-type VZV. No other possible cases of VZV reactivation have occurred with about 1178 months of follow-up. Live attenuated zoster vaccine appears generally safe in this population when vaccinated as noted; the overall vaccination risk needs to be weighed against the risk of wild-type VZV disease in this high-risk population.

  2. Titration of individual strains in trivalent live-attenuated influenza vaccine without neutralization.

    PubMed

    Sirinonthanawech, Naraporn; Surichan, Somchaiya; Namsai, Aphinya; Puthavathana, Pilaipan; Auewarakul, Prasert; Kongchanagul, Alita

    2016-11-01

    Formulation and quality control of trivalent live-attenuated influenza vaccine requires titration of infectivity of individual strains in the trivalent mix. This is usually performed by selective neutralization of two of the three strains and titration of the un-neutralized strain in cell culture or embryonated eggs. This procedure requires standard sera with high neutralizing titer against each of the three strains. Obtaining standard sera, which can specifically neutralize only the corresponding strain of influenza viruses and is able to completely neutralize high concentration of virus in the vaccine samples, can be a problem for many vaccine manufacturers as vaccine stocks usually have very high viral titers and complete neutralization may not be obtained. Here an alternative approach for titration of individual strain in trivalent vaccine without the selective neutralization is presented. This was done by detecting individual strains with specific antibodies in an end-point titration of a trivalent vaccine in cell culture. Similar titers were observed in monovalent and trivalent vaccines for influenza A H3N2 and influenza B strains, whereas the influenza A H1N1 strain did not grow well in cell culture. Viral interference among the vaccine strains was not observed. Therefore, providing that vaccine strains grow well in cell culture, this assay can reliably determine the potency of individual strains in trivalent live-attenuated influenza vaccines.

  3. Safety, tolerability, and immunogenicity of a recombinant, genetically engineered, live-attenuated vaccine against canine blastomycosis.

    PubMed

    Wüthrich, Marcel; Krajaejun, Theerapong; Shearn-Bochsler, Valerie; Bass, Chris; Filutowicz, Hanna I; Legendre, Alfred M; Klein, Bruce S

    2011-05-01

    Blastomycosis is a severe, commonly fatal infection caused by the dimorphic fungus Blastomyces dermatitidis in dogs that live in the United States, Canada, and parts of Africa. The cost of treating an infection can be expensive, and no vaccine against this infection is commercially available. A genetically engineered live-attenuated strain of B. dermatitidis lacking the major virulence factor BAD-1 successfully vaccinates against lethal experimental infection in mice. Here we studied the safety, toxicity, and immunogenicity of this strain as a vaccine in dogs, using 25 beagles at a teaching laboratory and 78 foxhounds in a field trial. In the beagles, escalating doses of live vaccine ranging from 2 × 10⁴ to 2 × 10⁷ yeast cells given subcutaneously were safe and did not disseminate to the lung or induce systemic illness, but a dose of < 2 × 10⁶ yeast cells induced less fever and local inflammation. A vaccine dose of 10⁵ yeast cells was also well tolerated in vaccinated foxhounds who had never had blastomycosis; however, vaccinated dogs with prior infection had more local reactions at the vaccine site. The draining lymph node cells and peripheral blood lymphocytes from vaccinated dogs demonstrated gamma interferon (IFN-γ), tumor necrosis factor alpha (TNF-α), and granulocyte-macrophage colony-stimulating factor (GM-CSF) specifically in response to stimulation with Blastomyces antigens. Thus, the live-attenuated vaccine against blastomycosis studied here proved safe, well tolerated, and immunogenic in dogs and merits further studies of vaccine efficacy.

  4. Experimental Infection of Richardson's Ground Squirrels (Spermophilus richardsonii) with Attenuated and Virulent Strains of Brucella abortus

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Exposure of non-target species to wildlife vaccines is an important concern when evaluating a candidate vaccine for use in the field. A previous investigation of the safety of Brucella abortus strain RB51 (sRB51) in various non-target species suggested that Richardson’s ground squirrels (Spermophil...

  5. The challenges of classical swine fever control: modified live and E2 subunit vaccines.

    PubMed

    Huang, Yu-Liang; Deng, Ming-Chung; Wang, Fun-In; Huang, Chin-Cheng; Chang, Chia-Yi

    2014-01-22

    Classical swine fever (CSF) is an economically important, highly contagious disease of swine worldwide. CSF is caused by classical swine fever virus (CSFV), and domestic pigs and wild boars are its only natural hosts. The two main strategies used to control CSF epidemic are systematic prophylactic vaccination and a non-vaccination stamping-out policy. This review compares the protective efficacy of the routinely used modified live vaccine (MLV) and E2 subunit vaccines and summarizes the factors that influence the efficacy of the vaccines and the challenges that both vaccines face to CSF control. Although MLV provide earlier and more complete protection than E2 subunit vaccines, it has the drawback of not allowing differentiation between infected and vaccinated animals (DIVA). The marker vaccine of E2 protein with companion discriminatory test to detect antibodies against E(rns) allows DIVA and is a promising strategy for future control and eradication of CSF. Maternal derived antibody (MDA) is the critical factor in impairing the efficacy of both MLV and E2 subunit vaccines, so the well-designed vaccination programs of sows and piglets should be considered together. Because of the antigen variation among various genotypes of CSFV, antibodies raised by either MLV or subunit vaccine neutralize genotypically homologous strains better than heterologous ones. However, although this is not a major concern for MLV as the induced immune responses can protect pigs against the challenge of various genotypes of CSFVs, it is critical for E2 subunit vaccines. It is thus necessary to evaluate whether the E2 subunit vaccine can completely protect against the current prevalent strains in the field. An ideal new generation of vaccine should be able to maintain the high protective efficiency of MLV and overcome the problem of antigenic variations while allowing for DIVA.

  6. Comparative genomics of the Mycobacterium signaling architecture and implications for a novel live attenuated Tuberculosis vaccine.

    PubMed

    Zhou, Peifu; Xie, Jianping

    2014-01-01

    Tuberculosis (TB), caused by Mycobacterium tuberculosis (M.tb), remains a major threat to global public health. A new TB vaccine affording superior immune protection to M. bovis Bacillus Calmette-Guérin (BCG) is imperative. The advantage of a live attenuated vaccine is that it can mimic the bona fide pathogen, elicit immune responses similar to natural infection, and potentially provide more protection than other vaccines. BCG, the only vaccine and a live attenuated vaccine that is the result of cumulative mutations by serial passage of M. bovis, has provided clues for the construction of novel improved vaccines. A strategy is put forward for identifying a new live attenuated TB vaccine generated by cumulative mutation based on M.tb. Given the important role of the M.tb signaling network consisting of a two-component system, eukaryotic-like Ser/Thr protein kinase system and sigma factor system based on comparisons among M.tb H37Rv, M. bovis, and BCG, we have put a premium on this signaling circuit as the starting point for the generation of an attenuated TB vaccine.

  7. The Case for Live Attenuated Vaccines against the Neglected Zoonotic Diseases Brucellosis and Bovine Tuberculosis

    PubMed Central

    Pandey, Aseem; Cabello, Ana; Akoolo, Lavoisier; Rice-Ficht, Allison; Arenas-Gamboa, Angela; McMurray, David; Ficht, Thomas A.; de Figueiredo, Paul

    2016-01-01

    Vaccination of humans and animals with live attenuated organisms has proven to be an effective means of combatting some important infectious diseases. In fact, the 20th century witnessed tremendous improvements in human and animal health worldwide as a consequence of large-scale vaccination programs with live attenuated vaccines (LAVs). Here, we use the neglected zoonotic diseases brucellosis and bovine tuberculosis (BTb) caused by Brucella spp. and Mycobacterium bovis (M. bovis), respectively, as comparative models to outline the merits of LAV platforms with emphasis on molecular strategies that have been pursued to generate LAVs with enhanced vaccine safety and efficacy profiles. Finally, we discuss the prospects of LAV platforms in the fight against brucellosis and BTb and outline new avenues for future research towards developing effective vaccines using LAV platforms. PMID:27537413

  8. Characterization of immune responses induced by inactivated, live attenuated and DNA vaccines against Japanese encephalitis virus in mice.

    PubMed

    Li, Jieqiong; Chen, Hui; Wu, Na; Fan, Dongying; Liang, Guodong; Gao, Na; An, Jing

    2013-08-28

    Vaccination is the most effective countermeasure for protecting individuals from Japanese encephalitis virus (JEV) infection. There are two types of JEV vaccines currently used in China: the Vero cell-derived inactivated vaccine and the live attenuated vaccine. In this study, we characterized the immune response and protective efficacy induced in mice by the inactivated vaccine, live attenuated vaccine and the DNA vaccine candidate pCAG-JME, which expresses JEV prM-E proteins. We found that the live attenuated vaccine conferred 100% protection and resulted in the generation of high levels of specific anti-JEV antibodies and cytokines. The pCAG-JME vaccine induced protective immunity as well as the live attenuated vaccine. Unexpectedly, immunization with the inactivated vaccine only induced a limited immune response and partial protection, which may be due to the decreased activity of dendritic cells and the expansion of CD4+CD25+Foxp3+ regulatory T cells observed in these mice. Altogether, our results suggest that the live attenuated vaccine is more effective in providing protection against JEV infection than the inactivated vaccine and that pCAG-JME will be a potential JEV vaccine candidate.

  9. Modified live virus vaccine induces a distinct immune response profile compared to inactivated influenza A virus vaccines in swine

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Genetic and antigenic diversity within H1 influenza A virus (IAV) subtypes circulating in swine is increasing. The need for cross-protective influenza vaccines in swine is necessary as the virus becomes more diverse. This study compared the humoral and cell-mediated immune response of modified live ...

  10. Efficacy of a live attenuated vaccine in classical swine fever virus postnatally persistently infected pigs.

    PubMed

    Muñoz-González, Sara; Perez-Simó, Marta; Muñoz, Marta; Bohorquez, José Alejandro; Rosell, Rosa; Summerfield, Artur; Domingo, Mariano; Ruggli, Nicolas; Ganges, Llilianne

    2015-07-09

    Classical swine fever (CSF) causes major losses in pig farming, with various degrees of disease severity. Efficient live attenuated vaccines against classical swine fever virus (CSFV) are used routinely in endemic countries. However, despite intensive vaccination programs in these areas for more than 20 years, CSF has not been eradicated. Molecular epidemiology studies in these regions suggests that the virus circulating in the field has evolved under the positive selection pressure exerted by the immune response to the vaccine, leading to new attenuated viral variants. Recent work by our group demonstrated that a high proportion of persistently infected piglets can be generated by early postnatal infection with low and moderately virulent CSFV strains. Here, we studied the immune response to a hog cholera lapinised virus vaccine (HCLV), C-strain, in six-week-old persistently infected pigs following post-natal infection. CSFV-negative pigs were vaccinated as controls. The humoral and interferon gamma responses as well as the CSFV RNA loads were monitored for 21 days post-vaccination. No vaccine viral RNA was detected in the serum samples and tonsils from CSFV postnatally persistently infected pigs for 21 days post-vaccination. Furthermore, no E2-specific antibody response or neutralising antibody titres were shown in CSFV persistently infected vaccinated animals. Likewise, no of IFN-gamma producing cell response against CSFV or PHA was observed. To our knowledge, this is the first report demonstrating the absence of a response to vaccination in CSFV persistently infected pigs.

  11. Comparison of the Effectiveness of Trivalent Inactivated Influenza Vaccine and Live, Attenuated Influenza Vaccine in Preventing Influenza-Like Illness among US Service Members, 2006-2009

    DTIC Science & Technology

    2012-11-26

    controlled studies. Vaccine 2012; 30:886–92. 11. Piedra PA, Gaglani MJ, Kozinetz CA, et al. Trivalent live attenuated intranasal influenza vaccine...120:e553–64. 12. Halloran ME, Piedra PA, Longini IM Jr, et al. Efficacy of trivalent, cold-adapted, influenza virus vaccine against influenza A (Fujian

  12. Optimization of efficacy of a live attenuated Flavobacterium psychrophilum immersion vaccine.

    PubMed

    Sudheesh, Ponnerassery S; Cain, Kenneth D

    2016-09-01

    This study was aimed at optimizing the efficacy of a recently developed live attenuated immersion vaccine (B.17-ILM) as a promising vaccine against bacterial coldwater disease (BCWD) caused by Flavobacterium psychrophilum in salmonids. Rainbow trout (RBT) fry were vaccinated by immersion, and different parameters affecting vaccination such as fish size, vaccine delivery time, dose, duration of protection, booster regimes and vaccine growth incubation time were optimized. Specific anti-F. psychrophilum immune response was determined by ELISA. Protective efficacy was determined by challenging with a virulent strain of F. psychrophilum (CSF-259-93) and calculating cumulative percent mortality (CPM) and relative percent survival (RPS). All vaccinated fish developed significantly higher levels of serum antibody titers by week 8 when compared to their respective controls. Immersion vaccination for 3, 6 and 30 min produced significant protection with comparable RPS values of 47%, 53% and 52%, respectively. This vaccine provided significant protection for fish as small as 0.5 g with an RPS of 55%; larger fish of 1 g and 2 g yielded slightly higher RPS values of 59% and 60%, respectively. Fish vaccinated with higher vaccine doses of ∼10(10) and 10(8) colony forming units mL(-1) (cfu ml(-1)) were strongly protected out to at least 24 weeks with RPS values up to 70%. Fish vaccinated with lower doses (∼10(6) and 10(5) cfu mL(-1)) had good protection out to 12 weeks, but RPS values dropped to 36% and 34%, respectively by 24 weeks. Vaccine efficacy was optimum when the primary vaccination was followed by a single booster (week 12 challenge RPS = 61%) rather than two boosters (week 12 challenge RPS = 48%). Vaccination without a booster resulted in a lower RPS (13%) indicating the necessity of a single booster vaccination to maximize efficacy. This study presents key findings that demonstrate the efficacy and commercial potential for this live attenuated BCWD

  13. Live porcine reproductive and respiratory syndrome virus vaccines: Current status and future direction.

    PubMed

    Renukaradhya, Gourapura J; Meng, Xiang-Jin; Calvert, Jay G; Roof, Michael; Lager, Kelly M

    2015-08-07

    Porcine reproductive and respiratory syndrome (PRRS) caused by PRRS virus (PRRSV) was reported in the late 1980s. PRRS still is a huge economic concern to the global pig industry with a current annual loss estimated at one billion US dollars in North America alone. It has been 20 years since the first modified live-attenuated PRRSV vaccine (PRRSV-MLV) became commercially available. PRRSV-MLVs provide homologous protection and help in reducing shedding of heterologous viruses, but they do not completely protect pigs against heterologous field strains. There have been many advances in understanding the biology and ecology of PRRSV; however, the complexities of virus-host interaction and PRRSV vaccinology are not yet completely understood leaving a significant gap for improving breadth of immunity against diverse PRRS isolates. This review provides insights on immunization efforts using infectious PRRSV-based vaccines since the 1990s, beginning with live PRRSV immunization, development and commercialization of PRRSV-MLV, and strategies to overcome the deficiencies of PRRSV-MLV through use of replicating viral vectors expressing multiple PRRSV membrane proteins. Finally, powerful reverse genetics systems (infectious cDNA clones) generated from more than 20 PRRSV isolates of both genotypes 1 and 2 viruses have provided a great resource for exploring many innovative strategies to improve the safety and cross-protective efficacy of live PRRSV vaccines. Examples include vaccines with diminished ability to down-regulate the immune system, positive and negative marker vaccines, multivalent vaccines incorporating antigens from other porcine pathogens, vaccines that carry their own cytokine adjuvants, and chimeric vaccine viruses with the potential for broad cross-protection against heterologous strains. To combat this devastating pig disease in the future, evaluation and commercialization of such improved live PRRSV vaccines is a shared goal among PRRSV researchers, pork

  14. Salmonella enterica serovar Typhi Live Vector Vaccines Finally Come of Age

    PubMed Central

    Galen, James E.; Pasetti, Marcela F.; Tennant, Sharon; Olveira-Ruiz, Patricia; Sztein, Marcelo B.; Levine, Myron M.

    2013-01-01

    Attenuated bacterial vaccine strains hold great promise as live vectors for presentation of foreign antigens from unrelated bacterial, viral, and parasitic pathogens to the immune system. While this approach has proven quite successful in experimental animal models for eliciting antigen-specific mucosal, humoral, and cellular responses, results have been disappointing for clinical trials carried out thus far. We hypothesize that the paucity of human responses to foreign antigens delivered by live vectors suggests that the strains and genetic approaches used to date have resulted in over-attenuated vaccine strains with severely reduced immunogenicity. However, remarkable advances have now been made in the genetics of foreign antigen expression, understanding mechanisms of live vector immunity, and refining immunization strategies. The time has now come for development of multivalent live vectors in which stable antigen expression is balanced with metabolic fitness to create highly immunogenic vaccines. PMID:19417771

  15. Oral vaccination reduces the incidence of tuberculosis in free-living brushtail possums

    PubMed Central

    Tompkins, D. M.; Ramsey, D. S. L.; Cross, M. L.; Aldwell, F. E.; de Lisle, G. W.; Buddle, B. M.

    2009-01-01

    Bovine tuberculosis (Tb) caused by Mycobacterium bovis has proved refractory to eradication from domestic livestock in countries with wildlife disease reservoirs. Vaccination of wild hosts offers a way of controlling Tb in livestock without wildlife culling. This study was conducted in a Tb-endemic region of New Zealand, where the introduced Australian brushtail possum (Trichosurus vulpecula) is the main wildlife reservoir of Tb. Possums were trapped and vaccinated using a prototype oral-delivery system to deliver the Tb vaccine bacille Calmette–Guerin. Vaccinated and control possums were matched according to age, sex and location, re-trapped bimonthly and assessed for Tb status by palpation and lesion aspiration; the site was depopulated after 2 years and post-mortem examinations were conducted to further identify clinical Tb cases and subclinical infection. Significantly fewer culture-confirmed Tb cases were recorded in vaccinated possums (1/51) compared with control animals (12/71); the transition probability from susceptible to infected was significantly reduced in both males and females by vaccination. Vaccine efficacy was estimated at 95 per cent (87–100%) for females and 96 per cent (82–99%) for males. Hence, this trial demonstrates that orally delivered live bacterial vaccines can significantly protect wildlife against natural disease exposure, indicating that wildlife vaccination, along with existing control methods, could be used to eradicate Tb from domestic animals. PMID:19493904

  16. Distinct Cross-reactive B-Cell Responses to Live Attenuated and Inactivated Influenza Vaccines

    PubMed Central

    Sasaki, Sanae; Holmes, Tyson H.; Albrecht, Randy A.; García-Sastre, Adolfo; Dekker, Cornelia L.; He, Xiao-Song; Greenberg, Harry B.

    2014-01-01

    Background. The immunological bases for the efficacies of the 2 currently licensed influenza vaccines, live attenuated influenza vaccine (LAIV) and inactivated influenza vaccine (IIV), are not fully understood. The goal of this study was to identify specific B-cell responses correlated with the known efficacies of these 2 vaccines. Methods. We compared the B-cell and antibody responses after immunization with 2010/2011 IIV or LAIV in young adults, focusing on peripheral plasmablasts 6–8 days after vaccination. Results. The quantities of vaccine-specific plasmablasts and plasmablast-derived polyclonal antibodies (PPAbs) in IIV recipients were significantly higher than those in LAIV recipients. No significant difference was detected in the avidity of vaccine-specific PPAbs between the 2 vaccine groups. Proportionally, LAIV induced a greater vaccine-specific immunoglobulin A plasmablast response, as well as a greater plasmablast response to the conserved influenza nuclear protein, than IIV. The cross-reactive plasmablast response to heterovariant strains, as indicated by the relative levels of cross-reactive plasmablasts and the cross-reactive PPAb binding reactivity, was also greater in the LAIV group. Conclusions. Distinct quantitative and qualitative patterns of plasmablast responses were induced by LAIV and IIV in young adults; a proportionally greater cross-reactive response was induced by LAIV. PMID:24676204

  17. Safety and immunogenicity of a live attenuated mumps vaccine

    PubMed Central

    Liang, Yan; Ma, Jingchen; Li, Changgui; Chen, Yuguo; Liu, Longding; Liao, Yun; Zhang, Ying; Jiang, Li; Wang, Xuan-Yi; Che, Yanchun; Deng, Wei; Li, Hong; Cui, Xiaoyu; Ma, Na; Ding, Dong; Xie, Zhongping; Cui, Pingfang; Ji, Qiuyan; Wang, Jingjing; Zhao, Yuliang; Wang, Junzhi; Li, Qihan

    2014-01-01

    Background: Mumps, a communicable, acute and previously well-controlled disease, has had recent and occasional resurgences in some areas. Methods: A randomized, double-blind, controlled and multistep phase I study of an F-genotype attenuated mumps vaccine produced in human diploid cells was conducted. A total of 300 subjects were enrolled and divided into 4 age groups: 16–60 years, 5–16 years, 2–5 years and 8–24 months. The groups were immunized with one injection per subject. Three different doses of the F-genotype attenuated mumps vaccine, A (3.5 ± 0.25 logCCID50), B (4.25 ± 0.25 logCCID50) and C (5.0 ± 0.25 logCCID50), as well as a placebo control and a positive control of a licensed A-genotype vaccine (S79 strain) were used. The safety and immunogenicity of this vaccine were compared with those of the controls. Results: The safety evaluation suggested that mild adverse reactions were observed in all groups. No serious adverse event (SAE) was reported throughout the trial. The immunogenicity test showed a similar seroconversion rate of the neutralizing and ELISA antibody in the 2- to 5-year-old and 8- to 24-month-old groups compared with the seroconversion rate in the positive control. The GMT of the neutralizing anti-F-genotype virus antibodies in the vaccine groups was slightly higher than that in the positive control group. Conclusions: The F-genotype attenuated mumps vaccine evaluated in this clinical trial was demonstrated to be safe and have effective immunogenicity vs. control. PMID:24614759

  18. Post-marketing surveillance of live-attenuated Japanese encephalitis vaccine safety in China.

    PubMed

    Wang, Yali; Dong, Duo; Cheng, Gang; Zuo, Shuyan; Liu, Dawei; Du, Xiaoxi

    2014-10-07

    Japanese encephalitis (JE) is the most severe form of viral encephalitis in Asia and no specific treatment is available. Vaccination provides an effective intervention to prevent JE. In this paper, surveillance data for adverse events following immunization (AEFI) related to SA-14-14-2 live-attenuated Japanese encephalitis vaccine (Chengdu Institute of Biological Products) was presented. This information has been routinely generated by the Chinese national surveillance system for the period 2009-2012. There were 6024 AEFI cases (estimated reported rate 96.55 per million doses). Most common symptoms of adverse events were fever, redness, induration and skin rash. There were 70 serious AEFI cases (1.12 per million doses), including 9 cases of meningoencephalitis and 4 cases of death. The post-marketing surveillance data add the evidence that the Chengdu institute live attenutated vaccine has a reasonable safety profile. The relationship between encephalitis and SA-14-14-2 vaccination should be further studied.

  19. CANINE DISTEMPER VIRUS ANTIBODY TITERS IN DOMESTIC CATS AFTER DELIVERY OF A LIVE ATTENUATED VIRUS VACCINE.

    PubMed

    Ramsay, Edward; Sadler, Ryan; Rush, Robert; Seimon, Tracie; Tomaszewicz, Ania; Fleetwood, Ellen A; McAloose, Denise; Wilkes, Rebecca P

    2016-06-01

    Three methods for delivering a live attenuated canine distemper virus (CDV) vaccine to domestic cats ( Felis catus ) were investigated, as models for developing vaccination protocols for tigers (Panthera tigris). Twenty domestic cats were randomly divided into four treatment groups: saline injection (negative controls); and oral, intranasal, and subcutaneous vaccinates. Cats were injected with saline or a CDV vaccine (Nobivac DP, Merck) at wk 0 and 4. Blood and nasal swabs were collected at wk 0 (prior to the initial vaccination) and weekly thereafter for 9 wk. Urine samples were collected on wk 1 to 9 after initial vaccination. Forty-nine weeks following the initial vaccination series, three cats from the subcutaneous group and three cats from the intranasal group were revaccinated. Blood was collected immediately prior, and 7 and 21 days subsequent to revaccination. Nasal swabs and urine samples were collected from each cat prior to wk 49 revaccination and daily for 7 days thereafter. Nasal swabs and urine were analyzed by quantitative PCR for vaccine virus presence. Sera were tested for CDV antibodies by virus neutralization. All cats were sero-negative for CDV antibodies at the beginning of the study, and saline-injected cats remained sero-negative throughout the study. A dramatic anamnestic response was seen following wk 4 subcutaneous vaccinations, with titers peaking at wk 6 (geometric mean = 2,435.5). Following wk 49 revaccination, subcutaneous vaccinates again mounted impressive titers (wk 52 geometric mean = 2,048). Revaccination of the intranasal group cats at wk 49 produced a small increase in titers (wk 52 geometric mean = 203). CDV viral RNA was detected in six nasal swabs but no urine samples, demonstrating low viral shedding postvaccination. The strong antibody response to subcutaneous vaccination and the lack of adverse effects suggest this vaccine is safe and potentially protective against CDV infection in domestic cats.

  20. Protective efficacy of a live attenuated vaccine against Argentine hemorrhagic fever. AHF Study Group.

    PubMed

    Maiztegui, J I; McKee, K T; Barrera Oro, J G; Harrison, L H; Gibbs, P H; Feuillade, M R; Enria, D A; Briggiler, A M; Levis, S C; Ambrosio, A M; Halsey, N A; Peters, C J

    1998-02-01

    Argentine hemorrhagic fever (AHF), caused by the arenavirus Junin, is a major public health problem among agricultural workers in Argentina. A prospective, randomized, double-blind, placebo-controlled, efficacy trial of Candid 1, a live attenuated Junin virus vaccine, was conducted over two consecutive epidemic seasons among 6500 male agricultural workers in the AHF-endemic region. Twenty-three men developed laboratory-confirmed AHF during the study; 22 received placebo and 1 received vaccine (vaccine efficacy 95%; 95% confidence interval [CI], 82%-99%). Three additional subjects in each group developed laboratory-confirmed Junin virus infection associated with mild illnesses that did not fulfill the clinical case definition for AHF, yielding a protective efficacy for prevention of any illness associated with Junin virus infection of 84% (95% CI, 60%-94%). No serious adverse events were attributed to vaccination. Candid 1, the first vaccine for the prevention of illness caused by an arenavirus, is safe and highly efficacious.

  1. Live Attenuated S. Typhimurium Vaccine with Improved Safety in Immuno-Compromised Mice

    PubMed Central

    Periaswamy, Balamurugan; Maier, Lisa; Vishwakarma, Vikalp; Slack, Emma; Kremer, Marcus; Andrews-Polymenis, Helene L.; McClelland, Michael; Grant, Andrew J.; Suar, Mrutyunjay; Hardt, Wolf-Dietrich

    2012-01-01

    Live attenuated vaccines are of great value for preventing infectious diseases. They represent a delicate compromise between sufficient colonization-mediated adaptive immunity and minimizing the risk for infection by the vaccine strain itself. Immune defects can predispose to vaccine strain infections. It has remained unclear whether vaccine safety could be improved via mutations attenuating a vaccine in immune-deficient individuals without compromising the vaccine's performance in the normal host. We have addressed this hypothesis using a mouse model for Salmonella diarrhea and a live attenuated Salmonella Typhimurium strain (ssaV). Vaccination with this strain elicited protective immunity in wild type mice, but a fatal systemic infection in immune-deficient cybb−/−nos2−/− animals lacking NADPH oxidase and inducible NO synthase. In cybb−/−nos2−/− mice, we analyzed the attenuation of 35 ssaV strains carrying one additional mutation each. One strain, Z234 (ssaV SL1344_3093), was >1000-fold attenuated in cybb−/−nos2−/− mice and ≈100 fold attenuated in tnfr1−/− animals. However, in wt mice, Z234 was as efficient as ssaV with respect to host colonization and the elicitation of a protective, O-antigen specific mucosal secretory IgA (sIgA) response. These data suggest that it is possible to engineer live attenuated vaccines which are specifically attenuated in immuno-compromised hosts. This might help to improve vaccine safety. PMID:23029007

  2. The role of non-human primates in the neurological safety of live viral vaccines (review).

    PubMed

    Levenbook, Inessa

    2011-01-01

    This review covers comprehensive data accumulated during the long history of using monkeys in the determination of neurovirulence activity and safety of live poliomyelitis, flaviviral, smallpox and mumps vaccines, as well as newly developed transgenic mouse and molecular-biological tests. The review also analyzes processes caused by some of these viruses in infant rodents (mice, rats) and evaluates the role of these processes in vaccine safety control. Recommendations resulting from this analysis are presented.

  3. Development of TV003/TV005, a single dose, highly immunogenic live attenuated dengue vaccine; what makes this vaccine different from the Sanofi-Pasteur CYD™ vaccine?

    PubMed

    Whitehead, Stephen S

    2016-01-01

    Dengue is caused by four serotype-distinct dengue viruses (DENVs), and developing a multivalent vaccine against dengue has not been straightforward since partial immunity to DENV may predispose to more severe disease upon subsequent DENV infection. The vaccine that is furthest along in development is CYD™, a live attenuated tetravalent vaccine (LATV) produced by Sanofi Pasteur. Although the multi-dose vaccine demonstrated protection against severe dengue, its overall efficacy was limited by DENV serotype, serostatus at vaccination, region and age. The National Institute of Allergy and Infectious Diseases has developed the LATV dengue vaccines TV003/TV005. A single dose of either TV003 or TV005 induced seroconversion to four DENV serotypes in 74-92% (TV003) and 90% (TV005) of flavivirus seronegative adults and elicited near-sterilizing immunity to a second dose of vaccine administered 6-12 months later. The important differences in the structure, infectivity and immune responses to TV003/TV005 are compared with CYD™.

  4. Oral vaccination against mycoplasmal pneumonia of swine using a live Erysipelothrix rhusiopathiae vaccine strain as a vector.

    PubMed

    Ogawa, Yohsuke; Oishi, Eiji; Muneta, Yoshihiro; Sano, Akiyuki; Hikono, Hirokazu; Shibahara, Tomoyuki; Yagi, Yukio; Shimoji, Yoshihiro

    2009-07-16

    Erysipelothrix rhusiopathiae Koganei 65-0.15 strain, the live swine erysipelas vaccine for subcutaneous injection, has been shown to colonize the tonsils of pigs after oral inoculation. We thus evaluated the possible use of the strain as a vector for oral vaccination against mycoplasmal pneumonia of swine. Recombinant E. rhusiopathiae strains expressing the C-terminal domain of the P97 adhesin of Mycoplasma hyopneumoniae were constructed and examined for vaccine efficacy in mice and pigs. Mice subcutaneously inoculated with the recombinant strains were protected from challenge exposure to a virulent E. rhusiopathiae. Administration of milk replacer containing recombinant E. rhusiopathiae expressing the M. hyopneumoniae protein protected pigs from death after exposure to E. rhusiopathiae and significantly reduced the severity of pneumonic lung lesions caused by infection with M. hyopneumoniae.

  5. Successful comeback of the single-dose live oral cholera vaccine CVD 103-HgR.

    PubMed

    Herzog, Christian

    2016-01-01

    Effective and easy to administer cholera vaccines are in need more than ever, for at risk populations and travellers alike. In many parts of the world cholera is still endemic, causing outbreaks and constituting repeatedly serious public health problems. The oral live cholera vaccine CVD 103-HgR (Orochol, Mutachol), the first genetically modified organism (GMO) used as vaccine, was in its time (launched 1993, Switzerland) the ideal cholera vaccine: single-dose, protective efficacy of 80-100% against moderate to severe cholera, acting within 8 days and exhibiting excellent safety, indiscernible from placebo. However, there were strong headwinds: In the 1990s the indication for cholera vaccines was generally downplayed by experts and in 1997 the European Commission called for a moratorium of GMOs which blocked the registration in the European Union. Thus, demand for this vaccine remained low and in 2003 it was taken off the market for economic reasons. After a decade in obscurity it (Vaxchora) has resurfaced again, now produced in the U.S. and equipped with a U.S. FDA license (June 10, 2016). What had happened? This commentary gives a critical account of an almost unbelievable string of misadventures, emerging adverse circumstances and man-made failures which nearly killed this single-dose live oral cholera vaccine. The good news is that patience and persistence lead to success in the end, allowing good science to prevail for the benefit of those in need.

  6. RECOMMENDATIONS FOR LIVE VIRAL AND BACTERIAL VACCINES IN IMMUNODEFICIENT PATIENTS AND THEIR CLOSE-CONTACTS

    PubMed Central

    Shearer, William T.; Fleisher, Thomas A.; Buckley, Rebecca H.; Ballas, Zuhair; Ballow, Mark; Blaese, R. Michael; Bonilla, Francisco A.; Conley, Mary Ellen; Charlotte-Cunningham-Rundles; Filipovich, Alexandra H.; Fuleihan, Ramsay; Gelfand, Erwin W.; Hernandez-Trujillo, Vivian; Holland, Steven M.; Hong, Richard; Lederman, Howard M.; Malech, Harry L.; Miles, Stephen; Notarangelo, Luigi D.; Ochs, Hans D.; Orange, Jordan S.; Puck, Jennifer M.; Routes, John M.; Stiehm, E. Richard; Sullivan, Kathleen; Torgerson, Troy; Winkelstein, Jerry

    2014-01-01

    The present uncertainty of which live viral or bacterial vaccines may be given to immune deficient patients and the growing neglect of societal adherence to routine immunizations has prompted the Medical Advisory Committee of the Immune Deficiency Foundation to issue recommendations based upon published literature and the collective experience of the committee members. These recommendations address the concern for immunodeficient patients acquiring infections from healthy individuals who have not been immunized or who are shedding live vaccine-derived viral or bacterial organisms. Such transmission of infectious agents may occur within the hospital, clinic, home, or at any public gathering. Collectively, we define this type transmission as close-contact spread of infectious disease that is particularly relevant in patients with impaired immunity who may develop infection when exposed to individuals carrying vaccine-preventable infectious diseases or who have recently received a live vaccine. Immunodeficient patients who have received therapeutic hematopoietic stem transplantation are also at risk during the time when immune reconstitution is incomplete or while they are on immunosuppressive agents to prevent or treat graft-versus-host disease. This review recommends the general education of what is known about vaccine-preventable or vaccine-derived diseases being spread to immunodeficient patients at risk for close-contact spread of infection, and describes the relative risks for a child with severe immunodeficiency. The review also recommends a balance between the need to protect vulnerable individuals with their social needs to integrate into society, attend school, and benefit from peer education. PMID:24582311

  7. [Studies on virulence of HIV and development of non-virulent live AIDS vaccine using monkeys].

    PubMed

    Hayami, Masanori; Horiuchi, Reii

    2004-06-01

    A great effort for developing AIDS vaccine has been carried out in the world, designed by various new ideas based on basic research information obtained in recent virology and immunology. Withall it, to obtain effective AIDS vaccine is considered skeptical. One of the reasons of its difficulty is a lack of experimental animals susceptible to HIV-1. In our laboratory, we have succeeded in developing chimeric SIV having 3' half of HIV-1 genome including env (SHIV), which is infectious to macaque monkeys. One of SHIVs has been proved nonpathogenic in monkeys from various aspects and it afforded protective immunity to monkeys against pathogenic SHIV challenge infection. Now, we are trying to develop anti-HIV live attenuated vaccines using the nonpathogenic SHIV as a starting material. In the history of virus vaccine, live attenuated vaccines have been proved most effective in measles and polio-myelitis. However, it is not clear whether nonpathogenic HIV exists or not. Futhermore, even if nonpathogenic HIV could be obtained, there is possibility that it will easily mutate to pathogenic one. Therefore, to develop live attenuated AIDS vaccine is considered dangerous. In this article, We will introduce our research on SHIV pathogenicity using monkeys and hypothesize possibility to obtain nonpathogenic HIV which is speculated from the origin and evolution of HIV/SIV. To clarify virulence and nonvirulence of HIV and to obtain nonpathogenic virus are not only applied research but also basic science to dissolve the fundemental question why HIV can induce the disease.

  8. Genetically modified, live attenuated dengue virus type 3 vaccine candidates.

    PubMed

    Blaney, Joseph E; Hanson, Christopher T; Firestone, Cai-Yen; Hanley, Kathryn A; Murphy, Brian R; Whitehead, Stephen S

    2004-12-01

    Three novel recombinant dengue type 3 (DEN3) virus vaccine candidates have been generated from a DEN3 virus isolated from a mild outbreak of dengue fever in the Sleman area of central Java in Indonesia in 1978. Antigenic chimeric viruses were prepared by replacing the membrane precursor and envelope (ME) proteins of recombinant DEN4 (rDEN4) virus with those from DEN3 Sleman/78 in the presence (rDEN3/4Delta30(ME)) and the absence (rDEN3/4(ME)) of the Delta30 mutation, a previously described 30-nucleotide deletion in the 3' untranslated region. In addition, a full-length infectious cDNA clone was generated from the DEN3 isolate and used to produce rDEN3 virus and the vaccine candidate rDEN3Delta30. The chimeric viruses rDEN3/4(ME) and rDEN3/4Delta30(ME) appear to be acceptable vaccine candidates since they were restricted in replication in severe combined immune deficiency mice transplanted with human hepatoma cells, in rhesus monkeys, and in Aedes and Toxorynchites mosquitoes, and each was protective in rhesus monkeys against DEN3 virus challenge. The rDEN3/4(ME) and rDEN3/4Delta30(ME) viruses were comparable in all parameters evaluated, indicating that antigenic chimerization resulted in the observed high level of attenuation. Surprisingly, rDEN3Delta30 was not attenuated in any model tested when compared with wild-type rDEN3 and therefore, is not a vaccine candidate at present. Thus, the rDEN3/4(ME) and rDEN3/4Delta30(ME) antigenic chimeric viruses can be considered for evaluation in humans and for inclusion in a tetravalent dengue vaccine.

  9. [PERSPECTIVES OF DEVELOPMENT OF LIVE RECOMBINANT ANTHRAX VACCINES BASED ON OPPORTUNISTIC AND APATHOGENIC MICROORGANISMS].

    PubMed

    Popova, P Yu; Mikshis, N I

    2016-01-01

    Live genetic engineering anthrax vaccines on the platform of avirulent and probiotic micro-organisms are a safe and adequate alternative to preparations based on attenuated Bacillus anthracis strains. Mucosal application results in a direct contact of the vaccine preparations with mucous membranes in those organs arid tissues of the macro-organisms, that are exposed to the pathogen in the first place, resulting in a development of local and systemic immune response. Live recombinant anthrax vaccines could be used both separately as well as in a prime-boost immunization scheme. The review focuses on immunogenic and protective properties of experimental live genetic engineering prearations, created based on members of geni of Salmonella, Lactobacillus and adenoviruses.

  10. Room Temperature Stabilization of Oral, Live Attenuated Salmonella enterica serovar Typhi-Vectored Vaccines

    PubMed Central

    Ohtake, Satoshi; Martin, Russell; Saxena, Atul; Pham, Binh; Chiueh, Gary; Osorio, Manuel; Kopecko, Dennis; Xu, DeQi; Lechuga-Ballesteros, David; Truong-Le, Vu

    2011-01-01

    Foam drying, a modified freeze drying process, was utilized to produce a heat-stable, live attenuated Salmonella Typhi ‘Ty21a’ bacterial vaccine. Ty21a vaccine was formulated with pharmaceutically approved stabilizers, including sugars, plasticizers, amino acids, and proteins. Growth media and harvesting conditions of the bacteria were also studied to enhance resistance to desiccation stress encountered during processing as well as subsequent storage at elevated temperatures. The optimized Ty21a vaccine, formulated with trehalose, methionine, and gelatin, demonstrated stability for approximately 12 weeks at 37°C (i.e., time required for the vaccine to decrease in potency by 1log10 CFU) and no loss in titer at 4 and 25°C following storage for the same duration. Furthermore, the foam dried Ty21a elicited a similar immunogenic response in mice as well as protection in challenge studies compared to Vivotif™, the commercial Ty21a vaccine. The enhanced heat stability of the Ty21a oral vaccine, or Ty21a derivatives expressing foreign antigens (e.g. anthrax), could mitigate risks of vaccine potency loss during long term storage, shipping, delivery to geographical areas with warmer climates or during emergency distribution following a bioterrorist attack. Because the foam drying process is conducted using conventional freeze dryers and can be readily implemented at any freeze drying manufacturing facility, this technology appears ready and appropriate for large scale processing of foam dried vaccines. PMID:21300096

  11. Inactivated and live, attenuated influenza vaccines protect mice against influenza: Streptococcus pyogenes super-infections.

    PubMed

    Chaussee, Michael S; Sandbulte, Heather R; Schuneman, Margaret J; Depaula, Frank P; Addengast, Leslie A; Schlenker, Evelyn H; Huber, Victor C

    2011-05-12

    Mortality associated with influenza virus super-infections is frequently due to secondary bacterial complications. To date, super-infections with Streptococcus pyogenes have been studied less extensively than those associated with Streptococcus pneumoniae. This is significant because a vaccine for S. pyogenes is not clinically available, leaving vaccination against influenza virus as our only means for preventing these super-infections. In this study, we directly compared immunity induced by two types of influenza vaccine, either inactivated influenza virus (IIV) or live, attenuated influenza virus (LAIV), for the ability to prevent super-infections. Our data demonstrate that both IIV and LAIV vaccines induce similar levels of serum antibodies, and that LAIV alone induces IgA expression at mucosal surfaces. Upon super-infection, both vaccines have the ability to limit the induction of pro-inflammatory cytokines within the lung, including IFN-γ which has been shown to contribute to mortality in previous models of super-infection. Limiting expression of these pro-inflammatory cytokines within the lungs subsequently limits recruitment of macrophages and neutrophils to pulmonary surfaces, and ultimately protects both IIV- and LAIV-vaccinated mice from mortality. Despite their overall survival, both IIV- and LAIV-vaccinated mice demonstrated levels of bacteria within the lung tissue that are similar to those seen in unvaccinated mice. Thus, influenza virus:bacteria super-infections can be limited by vaccine-induced immunity against influenza virus, but the ability to prevent morbidity is not complete.

  12. Safe Live Oral Salmonella Vaccines; Use of aro- Strains.

    DTIC Science & Technology

    1983-05-20

    Department of the Army position unless so designated by other authorized documents. 7, S"|ECuRITY CLASSIFICATION Or THIS PAGE (W*PR Deem Enteewd) REPORT...properties justifying trial as oral-route vaccine in human volunteers will soon he completed. If such a strain gives satisfactory results, in respect of...biosynthetic (aro) both in biotype and in that it is virulent for calves’?. A nLn- pathway. A complete block at any .step of this pathway should reverting

  13. Vaccination strategies for managing brucellosis in Yellowstone bison.

    PubMed

    Treanor, John J; Johnson, Joseph S; Wallen, Rick L; Cilles, Sara; Crowley, Philip H; Cox, John J; Maehr, David S; White, P J; Plumb, Glenn E

    2010-10-01

    Concerns over migratory bison (Bison bison) at Yellowstone National Park transmitting brucellosis (Brucella abortus) to cattle herds on adjacent lands led to proposals for bison vaccination. We developed an individual-based model to evaluate how brucellosis infection might respond under alternate vaccination strategies, including: (1) vaccination of female calves and yearlings captured at the park boundary when bison move outside the primary conservation area; (2) combining boundary vaccination with the remote delivery of vaccine to female calves and yearlings distributed throughout the park; and (3) vaccinating all female bison (including adults) during boundary capture and throughout the park using remote delivery of vaccine. Simulations suggested Alternative 3 would be most effective, with brucellosis seroprevalence decreasing by 66% (from 0.47 to 0.16) over a 30-year period resulting from 29% of the population receiving protection through vaccination. Under this alternative, bison would receive multiple vaccinations that extend the duration of vaccine protection and defend against recurring infection in latently infected animals. The initial decrease in population seroprevalence will likely be slow due to high initial seroprevalence (40-60%), long-lived antibodies, and the culling of some vaccinated bison that were subsequently exposed to field strain Brucella and reacted positively on serologic tests. Vaccination is unlikely to eradicate B. abortus from Yellowstone bison, but could be an effective tool for reducing the level of infection. Our approach and findings have applicability world-wide for managers dealing with intractable wildlife diseases that cross wildlife-livestock and wildlife-human interfaces and affect public health or economic well-being.

  14. Five-year antibody persistence in children after one dose of inactivated or live attenuated hepatitis A vaccine.

    PubMed

    Zhang, Zhilun; Zhu, Xiangjun; Hu, Yuansheng; Liang, Miao; Sun, Jin; Song, Yufei; Yang, Qi; Ji, Haiquan; Zeng, Gang; Song, Lifei; Chen, Jiangting

    2017-02-14

    In China, both inactivated hepatitis A (HA) vaccine and live attenuated HA vaccine are available. We conducted a trial to evaluate 5-year immune persistence induced by one dose of inactivated or live attenuated HA vaccines in children. Subjects with no HA vaccination history had randomly received one dose of inactivated or live attenuated HA vaccine at 18-60 months of age. Anti-HAV antibody concentrations were measured before vaccination and at the first, second, and fifth year after vaccination. Suspected cases of hepatitis A were monitored during the study period. A total of 332 subjects were enrolled and 182 provided evaluable serum samples at all planned time points. seropositive rate at 5 y was 85.9% in the inactivated HA vaccine group and 90.7% in the live attenuated HA vaccine group. GMCs were 76.3% mIU/ml (95% CI: 61.7 - 94.4) and 66.8mIU/ml (95% CI: 57.8 - 77.3), respectively. No significant difference in antibody persistence between 2 groups was found. No clinical hepatitis A case was reported. A single dose of an inactivated or live attenuated HA vaccine at 18-60 months of age resulted in high HAV seropositive rate and anti-HAV antibody concentrations that lasted for at least 5 y.

  15. Safety and immunogenicity of a live attenuated Japanese encephalitis chimeric virus vaccine (IMOJEV®) in children.

    PubMed

    Chokephaibulkit, K; Houillon, G; Feroldi, E; Bouckenooghe, A

    2016-01-01

    JE-CV (IMOJEV®, Sanofi Pasteur, France) is a live attenuated virus vaccine constructed by inserting coding sequences of the prM and E structural proteins of the Japanese encephalitis SA14-14-2 virus into the genome of yellow fever 17D virus. Primary immunization with JE-CV requires a single dose of the vaccine. This article reviews clinical trials of JE-CV in children aged up to 6 years conducted in countries across South-East Asia. Strong and persistent antibody responses were observed after single primary and booster doses, with 97% of children seroprotected up to five years after booster vaccination. Models of long-term antibody persistence predict a median duration of protection of approximately 30 years after a booster dose. The safety and reactogenicity profiles of JE-CV primary and booster doses are comparable to other widely used childhood vaccines.

  16. Generation of influenza A viruses as live but replication-incompetent virus vaccines.

    PubMed

    Si, Longlong; Xu, Huan; Zhou, Xueying; Zhang, Ziwei; Tian, Zhenyu; Wang, Yan; Wu, Yiming; Zhang, Bo; Niu, Zhenlan; Zhang, Chuanling; Fu, Ge; Xiao, Sulong; Xia, Qing; Zhang, Lihe; Zhou, Demin

    2016-12-02

    The conversion of life-threatening viruses into live but avirulent vaccines represents a revolution in vaccinology. In a proof-of-principle study, we expanded the genetic code of the genome of influenza A virus via a transgenic cell line containing orthogonal translation machinery. This generated premature termination codon (PTC)-harboring viruses that exerted full infectivity but were replication-incompetent in conventional cells. Genome-wide optimization of the sites for incorporation of multiple PTCs resulted in highly reproductive and genetically stable progeny viruses in transgenic cells. In mouse, ferret, and guinea pig models, vaccination with PTC viruses elicited robust humoral, mucosal, and T cell-mediated immunity against antigenically distinct influenza viruses and even neutralized existing infecting strains. The methods presented here may become a general approach for generating live virus vaccines that can be adapted to almost any virus.

  17. Superior protection elicited by live-attenuated vaccines in the murine model of paratuberculosis.

    PubMed

    Ghosh, Pallab; Shippy, Daniel C; Talaat, Adel M

    2015-12-16

    Mycobacterium avium subspecies paratuberculosis (M. paratuberculosis) causes Johne's disease, a chronic enteric infection in ruminants with severe economic impact on the dairy industry in the USA and worldwide. Currently, available vaccines have limited protective efficacy against disease progression and does not prevent spread of the infection among animals. Because of their ability to elicit wide-spectrum immune responses, we adopted a live-attenuated vaccine approach based on a sigH knock-out strain of M. paratuberculosis (ΔsigH). Earlier analysis of the ΔsigH mutant in mice indicated their inadequate ability to colonize host tissues, unlike the isogenic wild-type strain, validating the role of this sigma factor in M. paratuberculosis virulence. In the present study, we evaluated the performance of the ΔsigH mutant compared to inactivated vaccine constructs in a vaccine/challenge model of murine paratuberculosis. The presented analysis indicated that ΔsigH mutant with or without QuilA adjuvant is capable of eliciting strong immune responses (such as interferon gamma-γ, IFN-γ) suggesting their immunogenicity and ability to potentially initiate effective vaccine-induced immunity. Following a challenge with virulent strains of M. paratuberculosis, ΔsigH conferred protective immunity as indicated by the reduced bacterial burden accompanied with reduced lesions in main body organs (liver, spleen and intestine) usually infected with M. paratuberculosis. More importantly, our data indicated better ability of the ΔsigH vaccine to confer protection compared to the inactivated vaccine constructs even with the presence of oil-adjuvant. Overall, our approach provides a rational basis for using live-attenuated mutant strains to develop improved vaccines that elicit robust immunity against this chronic infection.

  18. Molecular characterization of chicken infectious anemia virus from contaminated live-virus vaccines.

    PubMed

    Li, Yang; Hu, Yan; Cui, Shuai; Fu, Jiayuan; Wang, Yixin; Cui, Zhizhong; Fang, Lichun; Chang, Shuang; Zhao, Peng

    2016-11-02

    The aim of this study was to investigate possible causes of the pervasiveness of chicken infectious anemia virus ( CIAV: ) infection in chickens in recent years in China. A total of 14 batches of live-virus vaccines were examined using PCR to detect CIAV contamination, of which only 2 samples (a Newcastle disease vaccine and a fowl pox vaccine) tested positive for CIAV. These Newcastle and fowl pox vaccines were then inoculated into 1-day-old specific-pathogen-free chickens. Serum samples were collected from chickens infected with the PCR-positive vaccines, and these tested positive for CIAV-specific antibodies as tested using ELISA. In addition, DNA samples isolated from the serum samples also tested positive by PCR. The results indicated that the samples were contaminated with CIAV and identified 2 exogenous CIAV strains, designated CIAV-N22 and CIAV-F10, in the respective samples. The full genome sequences of these novel CIAV strains were sequenced and analyzed. Phylogenetic tree analysis indicated that the CIAV-F10 strain might represent a recombinant viral strain arising from the parental CIAV strains JQ690762 and KJ728816. Overall, the results suggested that vaccination with CIAV-contaminated vaccines contributed to the prevalence and spread of CIAV infection in chickens. Furthermore, the CIAV contaminant was likely subsequently transmitted to commercial chickens through congenital transmission. Our findings therefore highlight the need for more extensive screening of live-virus vaccines for poultry in China to reduce the threat of contamination with exogenous viruses.

  19. A comparative study of live attenuated F strain-derived Mycoplasma gallisepticum vaccines

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Commercially available attenuated strains of Mycoplasma gallisepticum (MG) are commonly used within the layer industry to control MG-induced mycoplasmosis. Among these are two live MG vaccines derived from the moderately pathogenic MG “chick F” strain. In the present study, the commercially availa...

  20. ALLERGY REACTIONS IN PERSONS INOCULATED CUTANEOUSLY WITH LIVE EGG-YOLK TULAREMIA VACCINE

    DTIC Science & Technology

    Live egg -yolk tularemia vaccine used cutaneously causes in the human organism the same special intradermal allergy reaction to tularemia as does...tularemia was distinguished by sharpness during the entire period of observations, in the following proportions: during the first month after

  1. Development of live attenuated Streptococcus agalactiae as potential vaccines by selecting for resistance to sparfloxacin

    Technology Transfer Automated Retrieval System (TEKTRAN)

    To develop attenuated bacteria as potential live vaccines, sparfloxacin was used in this study to modify 40 isolates of Streptococcus agalactiae. Majority of S. agalactiae used in this study were able to develop at least 80-fold resistance to sparfloxacin. When the virulence of the sparfloxacin-resi...

  2. Envelope exchange for the generation of live-attenuated arenavirus vaccines.

    PubMed

    Bergthaler, Andreas; Gerber, Nicolas U; Merkler, Doron; Horvath, Edit; de la Torre, Juan Carlos; Pinschewer, Daniel D

    2006-06-01

    Arenaviruses such as Lassa fever virus cause significant mortality in endemic areas and represent potential bioterrorist weapons. The occurrence of arenaviral hemorrhagic fevers is largely confined to Third World countries with a limited medical infrastructure, and therefore live-attenuated vaccines have long been sought as a method of choice for prevention. Yet their rational design and engineering have been thwarted by technical limitations. In addition, viral genes had not been identified that are needed to cause disease but can be deleted or substituted to generate live-attenuated vaccine strains. Lymphocytic choriomeningitis virus, the prototype arenavirus, induces cell-mediated immunity against Lassa fever virus, but its safety for humans is unclear and untested. Using this virus model, we have developed the necessary methodology to efficiently modify arenavirus genomes and have exploited these techniques to identify an arenaviral Achilles' heel suitable for targeting in vaccine design. Reverse genetic exchange of the viral glycoprotein for foreign glycoproteins created attenuated vaccine strains that remained viable although unable to cause disease in infected mice. This phenotype remained stable even after extensive propagation in immunodeficient hosts. Nevertheless, the engineered viruses induced T cell-mediated immunity protecting against overwhelming systemic infection and severe liver disease upon wild-type virus challenge. Protection was established within 3 to 7 d after immunization and lasted for approximately 300 d. The identification of an arenaviral Achilles' heel demonstrates that the reverse genetic engineering of live-attenuated arenavirus vaccines is feasible. Moreover, our findings offer lymphocytic choriomeningitis virus or other arenaviruses expressing foreign glycoproteins as promising live-attenuated arenavirus vaccine candidates.

  3. Novel methods for expression of foreign antigens in live vector vaccines

    PubMed Central

    Wang, Jin Yuan; Harley, Regina H.; Galen, James E.

    2013-01-01

    Bacterial live vector vaccines represent a vaccine development strategy that offers exceptional flexibility. In this approach, genes encoding protective antigens of unrelated bacterial, viral or parasitic pathogens are expressed in an attenuated bacterial vaccine strain that delivers these foreign antigens to the immune system, thereby eliciting relevant immune responses. Rather than expressing these antigens using low copy expression plasmids, here we pursue expression of foreign proteins from the live vector chromosome. Our strategy is designed to compensate for the inherent disadvantage of loss of gene dosage (vs. plasmid-based expression) by integrating antigen-encoding gene cassettes into multiple chromosomal sites already inactivated in an attenuated Salmonella enterica serovar Typhi vaccine candidate. We tested expression of a cassette encoding the green fluorescent protein (GFPuv) integrated separately into native guaBA, htrA or clyA chromosomal loci. Using single integrations, we show that expression levels of GFPuv are significantly affected by the site of integration, regardless of the inclusion of additional strong promoters within the incoming cassette. Using cassettes integrated into both guaBA and htrA, we observe cumulative synthesis levels from two integration sites superior to single integrations. Most importantly, we observe that GFPuv expression increases in a growth phase-dependent manner, suggesting that foreign antigen synthesis may be “tuned” to the physiology of the live vaccine. We expect this novel platform expression technology to prove invaluable in the development of a wide variety of multivalent live vector vaccines, capable of expressing multiple antigens from both chromosomal and plasmid-based expression systems within a single strain. PMID:23406777

  4. In vitro analysis of virus particle subpopulations in candidate live-attenuated influenza vaccines distinguishes effective from ineffective vaccines.

    PubMed

    Marcus, Philip I; Ngunjiri, John M; Sekellick, Margaret J; Wang, Leyi; Lee, Chang-Won

    2010-11-01

    Two effective (vac+) and two ineffective (vac-) candidate live-attenuated influenza vaccines (LAIVs) derived from naturally selected genetically stable variants of A/TK/OR/71-delNS1[1-124] (H7N3) that differed only in the length and kind of amino acid residues at the C terminus of the nonstructural NS1 protein were analyzed for their content of particle subpopulations. These subpopulations included total physical particles (measured as hemagglutinating particles [HAPs]) with their subsumed biologically active particles of infectious virus (plaque-forming particles [PFPs]) and different classes of noninfectious virus, namely, interferon-inducing particles (IFPs), noninfectious cell-killing particles (niCKPs), and defective interfering particles (DIPs). The vac+ variants were distinguished from the vac- variants on the basis of their content of viral subpopulations by (i) the capacity to induce higher quantum yields of interferon (IFN), (ii) the generation of an unusual type of IFN-induction dose-response curve, (iii) the presence of IFPs that induce IFN more efficiently, (iv) reduced sensitivity to IFN action, and (v) elevated rates of PFP replication that resulted in larger plaques and higher PFP and HAP titers. These in vitro analyses provide a benchmark for the screening of candidate LAIVs and their potential as effective vaccines. Vaccine design may be improved by enhancement of attributes that are dominant in the effective (vac+) vaccines.

  5. Overexpression of Brucella putative glycosyltransferase WbkA in B. abortus RB51 leads to production of exopolysaccharide.

    PubMed

    Dabral, Neha; Jain-Gupta, Neeta; Seleem, Mohamed N; Sriranganathan, Nammalwar; Vemulapalli, Ramesh

    2015-01-01

    Brucella spp. are Gram-negative, facultative intracellular bacteria that cause brucellosis in mammals. Brucella strains containing the O-polysaccharide in their cell wall structure exhibit a smooth phenotype whereas the strains devoid of the polysaccharide show rough phenotype. B. abortus strain RB51 is a stable rough attenuated mutant which is used as a licensed live vaccine for bovine brucellosis. Previous studies have shown that the wboA gene, which encodes a glycosyltransferase required for the synthesis of O-polysaccharide, is disrupted in B. abortus RB51 by an IS711 element. Although complementation of strain RB51 with a functional wboA gene results in O-polysaccharide synthesis in the cytoplasm, it does not result in smooth phenotype. The aim of this study was to determine if overexpression of Brucella WbkA or WbkE, two additional putative glycosyltransferases essential for O-polysaccharide synthesis, in strain RB51 would result in the O-polysaccharide synthesis and smooth phenotype. Our results demonstrate that overexpression of wbkA or wbkE gene in RB51 does not result in O-polysaccharide expression as shown by Western blotting with specific antibodies. However, wbkA, but not wbkE, overexpression leads to the development of a clumping phenotype and the production of exopolysaccharide(s) containing mannose, galactose, N-acetylglucosamine, and N-acetylgalactosamine. Moreover, we found that the clumping recombinant strain displays increased adhesion to polystyrene plates. The recombinant strain was similar to strain RB51 in its attenuation characteristic and in its ability to induce protective immunity against virulent B. abortus challenge in mice.

  6. Immunogenicity and Safety of a Live Attenuated Zoster Vaccine (ZOSTAVAX™) in Korean Adults.

    PubMed

    Choi, Won Suk; Choi, Jung-Hyun; Choi, Jun Yong; Eom, Joong Sik; Kim, Sang Il; Pai, Hyunjoo; Peck, Kyong Ran; Sohn, Jang Wook; Cheong, Hee Jin

    2016-01-01

    A live attenuated zoster vaccine (ZOSTAVAX™, Merck & Co., Inc.) was approved by the Korea Ministry of Food and Drug Safety in 2009. However, the immunogenicity and safety of the vaccine has not been assessed in Korean population. This is multi-center, open-label, single-arm study performed with 180 healthy Korean adults ≥ 50 yr of age. The geometric mean titer (GMT) and geometric mean fold rise (GMFR) of varicella zoster virus (VZV) antibodies were measured by glycoprotein enzyme-linked immunosorbent assay (gpELISA) at 4 weeks post-vaccination. Subjects were followed for exposure to varicella or herpes zoster (HZ), the development of any varicella/varicella-like or HZ/HZ-like rashes, and any other clinical adverse experiences (AEs) for 42 days post-vaccination. For the 166 subjects included in the per-protocol population, the GMT at Day 1 was 66.9. At 4 weeks post-vaccination, the GMT for this population was 185.4, with a GMFR of 2.8 (95% CI, 2.5-3.1). Of the 180 subjects vaccinated, 62.8% experienced ≥ 1 AE, with 53.3% of subjects reporting injection-site AEs. The most frequently reported injection-site AEs were erythema (45.0%) with the majority being mild in intensity. Overall, 44 (24.4%) subjects experienced ≥ 1 systemic AE, 10 (5.5%) subjects experienced a systemic vaccine-related AE, and 3 (1.7%) subjects experienced ≥ 1 serious AE not related to vaccine. No subjects reported a VZV-like rash. There was no subject of death and no subject discontinued due to an adverse event. A single dose of zoster vaccine induced VZV-specific gpELISA antibody response and was generally well-tolerated in healthy Korean adults ≥50 yr of age (registry at www.clinicaltrial.gov No. NCT01556451).

  7. Molecular characterization of live Theileria parva sporozoite vaccine stabilates reveals extensive genotypic diversity.

    PubMed

    Patel, Ekta H; Lubembe, Donald M; Gachanja, James; Mwaura, Stephen; Spooner, Paul; Toye, Philip

    2011-06-30

    The current Infection and Treatment Method of vaccination against East Coast fever comprises an inoculation of live Theileria parva sporozoites and simultaneous administration of oxytetracycline. Immunization with a combination of parasite types has been shown to provide broader protection than inoculation of individual strains. In this study, we used a high-throughput capillary electrophoresis system to determine the genotypic composition of the Muguga Cocktail, a widely used vaccine stabilate derived from three seed stabilates-Muguga, Serengeti-transformed and Kiambu 5. Five satellite markers were used to genotype the vaccine and reference stabilates from two commercial-scale preparations of the vaccine. In addition, 224 cloned cell lines established by infection of bovine lymphocytes with T. parva parasites from the component stabilates were genotyped. The results indicate that, for the recently prepared batch, there are at least eight genotypes in each of the Muguga and the Serengeti-transformed stabilates, while parasites from the Kiambu 5 stabilate showed no diversity at the five loci. The Serengeti-transformed stabilate contained parasites of the Kiambu 5 genotype and of two genotypes present in the Muguga stabilate, whereas there were no genotypes common to the Muguga and Kiambu 5 stabilates. When stabilates from the two vaccine batches were compared, no allelic variations were identified between the Muguga and Kiambu 5 parasites, while lack of sufficient clones prevented a full comparison of the Serengeti-transformed stabilates. The findings will facilitate examination of the extent to which the vaccine strains become resident in areas under vaccination, the identification of 'breakthrough' strains and the establishment of the quality assurance protocols to detect variations in the production of the vaccine. The cloned cell lines will be useful for further understanding the antigenic diversity of parasites in the vaccine.

  8. Identification of upregulated genes in a modified live vaccine strain of Edwardsiella ictaluri compared to a virulent parent strain and characterization of novel DNA vaccine candidates

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Using PCR-select subtractive cDNA hybridization technique, 41 expressed sequence tags (EST's) were isolated from a modified live vaccine strain (AQUAVAC-ESC formerly RD-33) vs a virulent parent strain (EILO) of Edwardsiella ictaluri. Transcriptional levels of the 41 ESTs in the vaccine strain and th...

  9. Immune responses elicited to a live-attenuated influenza virus vaccine compared to a traditional whole-inactivated virus vaccine for pandemic H1N1in pigs

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In the United States there are currently two influenza vaccine platforms approved for use in humans - conventional inactivated virus and live-attenuated influenza virus (LAIV). One of the major challenges for influenza vaccination is designing a platform that provides cross-protection across strains...

  10. Immunogenicity and protective effect of recombinant Brucella abortus Ndk (rNdk) against a virulent strain B. abortus 544 infection in BALB/c mice.

    PubMed

    Hop, Huynh Tan; Simborio, Hannah Leah; Reyes, Alisha Wehdnesday Bernardo; Arayan, Lauren Togonon; Min, WonGi; Lee, Hu Jang; Kim, Dong Hee; Chang, Hong Hee; Kim, Suk

    2015-02-01

    In this study, we particularly evaluated the protective effect of recombinant protein encoded by Brucella abortus 544 ndk (nucleoside diphosphate kinase) gene against B. abortus infection in the BALB/c mice. Cloning and expression of B. abortus Ndk was accomplished by PCR amplification into a pMAL expression system, and purification of a recombinant Ndk (rNdk). As for the determination of IgG responses, rNdk induced vigorous IgG production, especially higher in IgG2a compared to IgG1 with titers of 5.2 and 4.8, respectively, whereas titers of these in mice immunized with MBP were 2.4 of IgG2a and 2.6 of IgG1. The analysis of cytokine has revealed that rNdk can strongly induce production of IFN-γ as well as proinflammatory cytokines (TNF, MCP1 and IL-6) but not much IL-10, suggesting rNdk elicited predominantly cell-mediated immune responses. Furthermore, the spleen proliferation and bacterial burden in the spleen of rNdk immunized mice were significantly lower than those of MBP-immunized mice against virulent B. abortus challenge (P < 0.01). Conclusionly, rNdk immunization enables to elicit both of the humoral and cellular response, ultimately enhancing protection level in experimental mice, suggesting that rNdk of B. abortus might be a useful candidate for subunit vaccine for brucellosis in animals.

  11. Cross-protection against Salmonella Typhimurium infection conferred by a live attenuated Salmonella Enteritidis vaccine.

    PubMed

    Nandre, Rahul M; Lee, Dajeong; Lee, John Hwa

    2015-01-01

    In this study, a genetically engineered live attenuated Salmonella Enteritidis (SE) vaccine was evaluated for its ability to protect against Salmonella Typhimurium (ST) infection in chickens. The birds were orally primed with the vaccine on the 1st day of life and given an oral booster at 5 wk of age. Control birds were orally inoculated with phosphate-buffered saline. Both groups of birds were orally challenged with a virulent ST strain at 9 wk of age. Compared with the control chickens, the vaccinated chickens had significantly higher levels of systemic IgG and mucosal IgA against specific ST antigens and a significantly greater lymphoproliferative response to ST antigens. The excretion of ST into the feces was significantly lower in the vaccinated group than in the control group on days 9 and 13 d after challenge. In addition, the vaccinated group had significantly fewer pronounced gross lesions in the liver and spleen and lower bacterial counts in the internal organs than the control group after challenge. These data indicate that genetically engineered live attenuated SE may induce humoral and cellular immune responses against ST antigens and may confer protection against virulent ST challenge.

  12. Cross-protection against Salmonella Typhimurium infection conferred by a live attenuated Salmonella Enteritidis vaccine

    PubMed Central

    Nandre, Rahul M.; Lee, Dajeong; Lee, John Hwa

    2015-01-01

    In this study, a genetically engineered live attenuated Salmonella Enteritidis (SE) vaccine was evaluated for its ability to protect against Salmonella Typhimurium (ST) infection in chickens. The birds were orally primed with the vaccine on the 1st day of life and given an oral booster at 5 wk of age. Control birds were orally inoculated with phosphate-buffered saline. Both groups of birds were orally challenged with a virulent ST strain at 9 wk of age. Compared with the control chickens, the vaccinated chickens had significantly higher levels of systemic IgG and mucosal IgA against specific ST antigens and a significantly greater lymphoproliferative response to ST antigens. The excretion of ST into the feces was significantly lower in the vaccinated group than in the control group on days 9 and 13 d after challenge. In addition, the vaccinated group had significantly fewer pronounced gross lesions in the liver and spleen and lower bacterial counts in the internal organs than the control group after challenge. These data indicate that genetically engineered live attenuated SE may induce humoral and cellular immune responses against ST antigens and may confer protection against virulent ST challenge. PMID:25673904

  13. Recombinant canine distemper virus serves as bivalent live vaccine against rabies and canine distemper.

    PubMed

    Wang, Xijun; Feng, Na; Ge, Jinying; Shuai, Lei; Peng, Liyan; Gao, Yuwei; Yang, Songtao; Xia, Xianzhu; Bu, Zhigao

    2012-07-20

    Effective, safe, and affordable rabies vaccines are still being sought. Attenuated live vaccine has been widely used to protect carnivores from canine distemper. In this study, we generated a recombinant canine distemper virus (CDV) vaccine strain, rCDV-RVG, expressing the rabies virus glycoprotein (RVG) by using reverse genetics. The recombinant virus rCDV-RVG retained growth properties similar to those of vector CDV in Vero cell culture. Animal studies demonstrated that rCDV-RVG was safe in mice and dogs. Mice inoculated intracerebrally or intramuscularly with rCDV-RVG showed no apparent signs of disease and developed a strong rabies virus (RABV) neutralizing antibody response, which completely protected mice from challenge with a lethal dose of street virus. Canine studies showed that vaccination with rCDV-RVG induced strong and long-lasting virus neutralizing antibody responses to RABV and CDV. This is the first study demonstrating that recombinant CDV has the potential to serve as bivalent live vaccine against rabies and canine distemper in animals.

  14. Protective efficacy afforded by live Pasteurella multocida vaccines in chickens is independent of lipopolysaccharide outer core structure.

    PubMed

    Harper, Marina; John, Marietta; Edmunds, Mark; Wright, Amy; Ford, Mark; Turni, Conny; Blackall, P J; Cox, Andrew; Adler, Ben; Boyce, John D

    2016-03-29

    Pasteurella multocida is a major animal pathogen that causes a range of diseases including fowl cholera. P. multocida infections result in considerable losses to layer and breeder flocks in poultry industries worldwide. Both killed whole-cell and live-attenuated vaccines are available; these vaccines vary in their protective efficacy, particularly against heterologous strains. Moreover, until recently there was no knowledge of P. multocida LPS genetics and structure to determine precisely how LPS structure affects the protective capacity of these vaccines. In this study we show that defined lipopolysaccharide (LPS) mutants presented as killed whole-cell vaccines elicited solid protective immunity only against P. multocida challenge strains expressing highly similar or identical LPS structures. This finding indicates that vaccination of commercial flocks with P. multocida killed cell formulations will not protect against strains producing an LPS structure different to that produced by strains included in the vaccine formulation. Conversely, protective immunity conferred by vaccination with live P. multocida strains was found to be largely independent of LPS structure. Birds vaccinated with a range of live mutants belonging to the L1 and L3 LPS genotypes, each expressing a specific truncated LPS structure, were protected against challenge with the parent strain. Moreover, birds vaccinated with any of the five LPS mutants belonging to the L1 LPS genotype were also protected against challenge with an unrelated strain and two of the five groups vaccinated with live LPS mutants belonging to the L3 genotype were protected against challenge with an unrelated strain. In summary, vaccination with live P. multocida aroA mutants producing full-length L1 or L3 LPS or vaccination with live strains producing shortened L1 LPS elicited strong protective immunity against both homologous and heterologous challenge.

  15. Adventitious agents and live viral vectored vaccines: Considerations for archiving samples of biological materials for retrospective analysis.

    PubMed

    Klug, Bettina; Robertson, James S; Condit, Richard C; Seligman, Stephen J; Laderoute, Marian P; Sheets, Rebecca; Williamson, Anna-Lise; Gurwith, Marc; Kochhar, Sonali; Chapman, Louisa; Carbery, Baevin; Mac, Lisa M; Chen, Robert T

    2016-12-12

    Vaccines are one of the most effective public health medicinal products with an excellent safety record. As vaccines are produced using biological materials, there is a need to safeguard against potential contamination with adventitious agents. Adventitious agents could be inadvertently introduced into a vaccine through starting materials used for production. Therefore, extensive testing has been recommended at specific stages of vaccine manufacture to demonstrate the absence of adventitious agents. Additionally, the incorporation of viral clearance steps in the manufacturing process can aid in reducing the risk of adventitious agent contamination. However, for live viral vaccines, aside from possible purification of the virus or vector, extensive adventitious agent clearance may not be feasible. In the event that an adventitious agent is detected in a vaccine, it is important to determine its origin, evaluate its potential for human infection and pathology, and discern which batches of vaccine may have been affected in order to take risk mitigation action. To achieve this, it is necessary to have archived samples of the vaccine and ancillary components, ideally from developmental through to current batches, as well as samples of the biological materials used in the manufacture of the vaccine, since these are the most likely sources of an adventitious agent. The need for formal guidance on such vaccine sample archiving has been recognized but not fulfilled. We summarize in this paper several prior major cases of vaccine contamination with adventitious agents and provide points for consideration on sample archiving of live recombinant viral vector vaccines for use in humans.

  16. A Low Gastric pH Mouse Model to Evaluate Live Attenuated Bacterial Vaccines

    PubMed Central

    Brenneman, Karen E.; Willingham, Crystal; Kilbourne, Jacquelyn A.; 3rd, Roy Curtiss; Roland, Kenneth L.

    2014-01-01

    The low pH of the stomach serves as a barrier to ingested microbes and must be overcome or bypassed when delivering live bacteria for vaccine or probiotic applications. Typically, the impact of stomach acidity on bacterial survival is evaluated in vitro, as there are no small animal models to evaluate these effects in vivo. To better understand the effect of this low pH barrier to live attenuated Salmonella vaccines, which are often very sensitive to low pH, we investigated the value of the histamine mouse model for this application. A low pH gastric compartment was transiently induced in mice by the injection of histamine. This resulted in a gastric compartment of approximately pH 1.5 that was capable of distinguishing between acid-sensitive and acid-resistant microbes. Survival of enteric microbes during gastric transit in this model directly correlated with their in vitro acid resistance. Because many Salmonella enterica serotype Typhi vaccine strains are sensitive to acid, we have been investigating systems to enhance the acid resistance of these bacteria. Using the histamine mouse model, we demonstrate that the in vivo survival of S. Typhi vaccine strains increased approximately 10-fold when they carried a sugar-inducible arginine decarboxylase system. We conclude that this model will be a useful for evaluating live bacterial preparations prior to clinical trials. PMID:24489912

  17. Anaplasma marginale Yucatan (Mexico) Strain. Assessment of low virulence and potential use as a live vaccine.

    PubMed

    Rodríguez Camarillo, Sergio D; García Ortiz, Miguel Angel; Rojas Ramírez, Edmundo E; Cantó Alarcón, Germinal J; Preciado de la Torre, Jesús F; Rosario Cruz, Rodrigo; Ramos Aragón, Juan A; Aboytes Torres, Ramón

    2008-12-01

    Anaplasma marginale Yucatan strain was found to have low virulence in cattle. We studied the virulence of this isolate by experimental inoculation of 113 susceptible cattle at increasing doses, after which only one animal required treatment for clinical disease. Subsequently, 104 cattle received a live vaccine of this strain by inoculation, which induced immunoprotection after heterologous challenged exposure with a different A. marginale isolate. In this study 14% of the immunized cattle required treatment as compared with the control nonimmunized cattle, in which 56% required treatment. The A. marginale vaccine strains used for the immunization studies had MSP1a variable regions that were different from those used for the challenge exposure.

  18. A reovirus challenge model applicable in commercial broilers after live vaccination.

    PubMed

    van Loon, A A W M; Suurland, B; van der Marel, P

    2002-02-01

    The efficacy of live reovirus vaccines may be determined by challenge via the foot pad route 3 to 4 weeks after vaccination. Swelling and discoloration in the foot pad and shank are scored for a period of 14 days. The major disadvantages of this challenge model are the subjective judgement of gross foot pad and/or shank lesions, that it is very difficult to induce lesions in broilers, and that it causes animal suffering. Other reovirus challenge models are based on reisolation of the virus from different tissues or on scoring microscopic lesions in the tendons. Some disadvantages of these models are that they either cannot be used after vaccination with live reovirus because they cannot discriminate between vaccine and challenge virus or that the microscopic lesions scored need not necessarily be related to the challenge virus but may have been induced by other factors. Therefore, we have attempted to develop a reovirus challenge model that was an improvement on the existing ones, using isolation of reovirus from different organs followed by specific detection of the challenge virus with a monoclonal antibody that can discriminate between challenge and vaccine virus. The reovirus challenge model was examined in specific pathogen free (SPF) White Leghorn chickens and commercial broilers. In vivo studies were conducted to examine the efficacy of an attenuated reovirus vaccine in SPF White Leghorn chickens and commercial broilers with maternal immunity against reovirus. No challenge virus could be detected in any of the organs of the vaccinated chickens 3 and 10 days after challenge. In contrast, challenge virus could be isolated from the unvaccinated control group. At an increased challenge dose all unvaccinated challenge control birds were positive, while the vaccinated chickens were protected. It was shown that 1-day-old vaccination in the presence of maternal immunity was effective. It seemed that protection induced in broilers by the attenuated reovirus vaccine

  19. Effects of partial deletion of the wzm and wzt genes on lipopolysaccharide synthesis and virulence of Brucella abortus S19.

    PubMed

    Wang, Xiuran; Wang, Lin; Lu, Tiancheng; Yang, Yanling; Chen, Si; Zhang, Rui; Lang, Xulong; Yan, Guangmou; Qian, Jing; Wang, Xiaoxu; Meng, Lingyi; Wang, Xinglong

    2014-06-01

    Brucellosis is a worldwide human and animal infectious disease, and the effective methods of its control are immunisation of animals by vaccination and elimination. Brucella abortus S19 is one of the popular vaccines with virulence in the control of cattle Brucellosis. In the present study, allelic exchange plasmids of wzm and wzt genes and partial knockout mutants of wzm and wzt were constructed to evaluate the resulting difference in virulence of B. abortus S19. PCR analysis revealed that the target genes were knocked out. The mutants were rough mutants and they could be differentiated from natural infection by the Rose Bengal plate and standard agglutination tests. The molecular weights of lipopolysaccharides of the Δwzm and Δwzt mutants were clustered between 25 and 40 kDa, and 30 and 35 kDa separately, and were markedly different from those in B. abortus S19. The virulence of B. abortus Δwzm and Δwzt was decreased compared with that of B. abortus S19 in mice. All these results identified that there were several differences between the wzm and wzt genes on lipopolysaccharide synthesis and on the virulence of B. abortus.

  20. Vaccination using live attenuated Leishmania donovani centrin deleted parasites induces protection in dogs against Leishmania infantum.

    PubMed

    Fiuza, Jacqueline Araújo; Gannavaram, Sreenivas; Santiago, Helton da Costa; Selvapandiyan, Angamuthu; Souza, Daniel Menezes; Passos, Lívia Silva Araújo; de Mendonça, Ludmila Zanandreis; Lemos-Giunchetti, Denise da Silveira; Ricci, Natasha Delaqua; Bartholomeu, Daniella Castanheira; Giunchetti, Rodolfo Cordeiro; Bueno, Lilian Lacerda; Correa-Oliveira, Rodrigo; Nakhasi, Hira L; Fujiwara, Ricardo Toshio

    2015-01-03

    Live attenuated Leishmania donovani parasites such as LdCen(-/-) have been shown elicit protective immunity against leishmanial infection in mice and hamster models. Previously, we have reported on the induction of strong immunogenicity in dogs upon vaccination with LdCen(-/-) including an increase in immunoglobulin isotypes, higher lymphoproliferative response, higher frequencies of activated CD4(+) and CD8(+) T cells, IFN-γ production by CD8(+) T cells, increased secretion of TNF-α and IL-12/IL-23p40 and, finally, decreased secretion of IL-4. To further explore the potential of LdCen(-/-) parasites as vaccine candidates, we performed a 24-month follow up of LdCen(-/-) immunized dogs after challenge with virulent Leishmania infantum, aiming determination of parasite burden by qPCR, antibody production (ELISA) and cellular responses (T cell activation and cytokine production) by flow cytometry and sandwich ELISA. Our data demonstrated that vaccination with a single dose of LdCen(-/-) (without any adjuvant) resulted in the reduction of up to 87.3% of parasite burden after 18 months of virulent challenge. These results are comparable to those obtained with commercially available vaccine in Brazil (Leishmune(®)). The protection was associated with antibody production and CD4(+) and CD8(+) proliferative responses, as well as T cell activation and significantly higher production of IFN-γ, IL-12/IL-23p40 and TNF-α, which was comparable to responses induced by immunization with Leishmune(®), with significant differences when compared to control animals (Placebo). Moreover, only animals immunized with LdCen(-/-) expressed lower levels of IL-4 when compared to animals vaccinated either with Leishmune(®) or PBS. Our results support further studies aiming to demonstrate the potential of genetically modified live attenuated L. donovani vaccine to control L. infantum transmission in endemic areas for CVL.

  1. Novel BVDV-2 mutants as new candidates for modified-live vaccines.

    PubMed

    Zemke, Johanna; König, Patricia; Mischkale, Katrin; Reimann, Ilona; Beer, Martin

    2010-04-21

    Protection against Bovine viral diarrhea virus (BVDV) type 2 infection of commercially available vaccines is often limited due to marked genetic and antigenic differences between BVDV types 1 (BVDV-1) and 2 (BVDV-2). Therefore, the immunogenicity of selected BVDV-1 and BVDV-2 mutants derived from infectious full-length cDNA clones and their use as modified-live vaccine candidates against challenge infection with a virulent heterologous BVDV-2 field isolate were investigated. Deletion mutants of BVDV-1 and BVDV-2 lacking a part of the N(pro) gene (BVDV-1DeltaN(pro)/BVDV-2DeltaN(pro)) were used as well as a packaged replicon with a deletion in the structural core protein encoding region (BVDV-2DeltaC-pseudovirions). The 25 calves used in this vaccination/challenge trial were allocated in five groups (n=5/group). One group received BVDV-1DeltaN(pro) (1 shot), one group BVDV-2DeltaN(pro) (1 shot), one group received both, BVDV-1DeltaN(pro) and BVDV-2DeltaN(pro) (1 shot), and one group was immunised with the BVDV-2DeltaC-pseudovirions (2 shots). The fifth group served as non-vaccinated control group. All groups were challenged intranasally with the BVDV-2 strain HI916 and monitored for signs of clinical disease, virus shedding and viremia. All tested BVDV vaccine candidates markedly reduced the outcome of the heterologous virulent BVDV-2 challenge infection showing graduated protective effects. The BVDV-2DeltaN(pro) mutant was able to induce complete protection and a "sterile immunity" upon challenge. Thus it represents a promising candidate for an efficacious future live vaccine.

  2. Response of layer and broiler strain chickens to parenteral administration of a live Salmonella Typhimurium vaccine.

    PubMed

    Groves, Peter J; Sharpe, Sue M; Cox, Julian M

    2015-07-01

    Responses to the parenteral administration of a live aroA deletion Salmonella serovar Typhimurium vaccine given to three brown egg layer strains and two broiler strains were studied. Twenty-five birds of each strain were reared together in floor pens to 6 weeks of age and then moved as individual strains to new floor pens and injected with 10(8) colony forming units (CFU) per bird of the vaccine bacteria intramuscularly or subcutaneously, 10(6) CFU per bird subcutaneously, or phosphate buffered saline (PBS) subcutaneously as a vaccination control. Three birds of one layer strain were injected intramuscularly with 0.5mg/ bird S. Typhimurium lipopolysaccharide (LPS) to evaluate whether response was similar for vaccine and endotoxin. Birds were weighed, and rectal temperatures recorded at the time of injection, then observed over 24 hours. Rectal temperatures were measured and blood samples collected for serum IL-6 assay at 3 hours post injection (PI). At 12 hours PI blood samples were drawn for analyses for plasma phosphorus (P), glucose (Glu), cholesterol (Cho), aspartate transaminase (AST), total protein (Ptn) and creatinine kinase (CK). Blood was sampled 14 days PI and tested for serum antibody to S. Typhimurium. Vaccination resulted in significant seroconversion by 14 days PI in all strains compared to the controls. The three layer strains exhibited a clinical malaise, evident within 90 minutes of injection, lasting for 12 hours, with complete recovery by 24 hours PI. Only the 10(8) CFU dose given subcutaneously produced an increase in rectal temperature 3 hours PI. Vaccination had no effect on IL-6 or Ptn. All vaccine doses increased P and the higher dose by either route decreased Cho in all bird strains. The 10(8) vaccine dose increased Glu and intramuscular injection markedly elevated CK only in the layer strains. The response was not completely congruous with that to LPS alone. The results highlight the need for consideration of differences in response of

  3. A genetically engineered live attenuated vaccine of Coccidioides posadasii protects BALB/c mice against coccidioidomycosis.

    PubMed

    Xue, Jianmin; Chen, Xia; Selby, Dale; Hung, Chiung-Yu; Yu, Jieh-Juen; Cole, Garry T

    2009-08-01

    Coccidioidomycosis (also known as San Joaquin Valley fever) is an occupational disease. Workers exposed to outdoor dust which contains spores of the soil-inhabiting fungus have a significantly increased risk of respiratory infection. In addition, people with compromised T-cell immunity, the elderly, and certain racial groups, particularly African-Americans and Filipinos, who live in regions of endemicity in the southwestern United States have an elevated incidence of symptomatic infection caused by inhalation of spores of Coccidioides posadasii or Coccidioides immitis. Recurring epidemics and escalation of medical costs have helped to motivate production of a vaccine against valley fever. The major focus has been the development of a defined, T-cell-reactive, recombinant protein vaccine. However, none of the products described to date have provided full protection to coccidioidal disease-susceptible BALB/c mice. Here we describe the first genetically engineered, live, attenuated vaccine that protects both BALB/c and C57BL/6 mice against coccidioidomycosis. Two chitinase genes (CTS2 and CTS3) were disrupted to yield the attenuated strain, which was unable to endosporulate and was no longer infectious. Vaccinated survivors mounted an immune response characterized by production of both T-helper-1- and T-helper-2-type cytokines. Histology revealed well-formed granulomas and markedly diminished inflammation. Significantly fewer organisms were observed in the lungs of survivors than in those of nonvaccinated mice. Additional investigations are required to further define the nature of the live, attenuated vaccine-induced immunity against Coccidioides infection.

  4. Oral Vaccination of Free-Living Badgers (Meles meles) with Bacille Calmette Guérin (BCG) Vaccine Confers Protection against Tuberculosis.

    PubMed

    Gormley, Eamonn; Ní Bhuachalla, Deirdre; O'Keeffe, James; Murphy, Denise; Aldwell, Frank E; Fitzsimons, Tara; Stanley, Paul; Tratalos, Jamie A; McGrath, Guy; Fogarty, Naomi; Kenny, Kevin; More, Simon J; Messam, Locksley L McV; Corner, Leigh A L

    2017-01-01

    A field trial was conducted to investigate the impact of oral vaccination of free-living badgers against natural-transmitted Mycobacterium bovis infection. For a period of three years badgers were captured over seven sweeps in three zones and assigned for oral vaccination with a lipid-encapsulated BCG vaccine (Liporale-BCG) or with placebo. Badgers enrolled in Zone A were administered placebo while all badgers enrolled in Zone C were vaccinated with BCG. Badgers enrolled in the middle area, Zone B, were randomly assigned 50:50 for treatment with vaccine or placebo. Treatment in each zone remained blinded until the end of the study period. The outcome of interest was incident cases of tuberculosis measured as time to seroconversion events using the BrockTB Stat-Pak lateral flow serology test, supplemented with post-mortem examination. Among the vaccinated badgers that seroconverted, the median time to seroconversion (413 days) was significantly longer (p = 0.04) when compared with non-vaccinated animals (230 days). Survival analysis (modelling time to seroconversion) revealed that there was a significant difference in the rate of seroconversion between vaccinated and non-vaccinated badgers in Zones A and C throughout the trial period (p = 0.015). For badgers enrolled during sweeps 1-2 the Vaccine Efficacy (VE) determined from hazard rate ratios was 36% (95% CI: -62%- 75%). For badgers enrolled in these zones during sweeps 3-6, the VE was 84% (95% CI: 29%- 97%). This indicated that VE increased with the level of vaccine coverage. Post-mortem examination of badgers at the end of the trial also revealed a significant difference in the proportion of animals presenting with M. bovis culture confirmed lesions in vaccinated Zone C (9%) compared with non-vaccinated Zone A (26%). These results demonstrate that oral BCG vaccination confers protection to badgers and could be used to reduce incident rates in tuberculosis-infected populations of badgers.

  5. Oral Vaccination of Free-Living Badgers (Meles meles) with Bacille Calmette Guérin (BCG) Vaccine Confers Protection against Tuberculosis

    PubMed Central

    Gormley, Eamonn; Ní Bhuachalla, Deirdre; O’Keeffe, James; Murphy, Denise; Aldwell, Frank E.; Fitzsimons, Tara; Stanley, Paul; Tratalos, Jamie A.; McGrath, Guy; Fogarty, Naomi; Kenny, Kevin; More, Simon J.; Messam, Locksley L. McV.; Corner, Leigh A. L.

    2017-01-01

    A field trial was conducted to investigate the impact of oral vaccination of free-living badgers against natural-transmitted Mycobacterium bovis infection. For a period of three years badgers were captured over seven sweeps in three zones and assigned for oral vaccination with a lipid-encapsulated BCG vaccine (Liporale-BCG) or with placebo. Badgers enrolled in Zone A were administered placebo while all badgers enrolled in Zone C were vaccinated with BCG. Badgers enrolled in the middle area, Zone B, were randomly assigned 50:50 for treatment with vaccine or placebo. Treatment in each zone remained blinded until the end of the study period. The outcome of interest was incident cases of tuberculosis measured as time to seroconversion events using the BrockTB Stat-Pak lateral flow serology test, supplemented with post-mortem examination. Among the vaccinated badgers that seroconverted, the median time to seroconversion (413 days) was significantly longer (p = 0.04) when compared with non-vaccinated animals (230 days). Survival analysis (modelling time to seroconversion) revealed that there was a significant difference in the rate of seroconversion between vaccinated and non-vaccinated badgers in Zones A and C throughout the trial period (p = 0.015). For badgers enrolled during sweeps 1–2 the Vaccine Efficacy (VE) determined from hazard rate ratios was 36% (95% CI: -62%– 75%). For badgers enrolled in these zones during sweeps 3–6, the VE was 84% (95% CI: 29%– 97%). This indicated that VE increased with the level of vaccine coverage. Post-mortem examination of badgers at the end of the trial also revealed a significant difference in the proportion of animals presenting with M. bovis culture confirmed lesions in vaccinated Zone C (9%) compared with non-vaccinated Zone A (26%). These results demonstrate that oral BCG vaccination confers protection to badgers and could be used to reduce incident rates in tuberculosis-infected populations of badgers. PMID:28121981

  6. Correlates of Immunity to Influenza as Determined by Challenge of Children with Live, Attenuated Influenza Vaccine

    PubMed Central

    Wright, Peter F.; Hoen, Anne G.; Ilyushina, Natalia A.; Brown, Eric P.; Ackerman, Margaret E.; Wieland-Alter, Wendy; Connor, Ruth I.; Jegaskanda, Sinthujan; Rosenberg-Hasson, Yael; Haynes, Brenda C.; Luke, Catherine J.; Subbarao, Kanta; Treanor, John J.

    2016-01-01

    Background. The efficacy of live, attenuated live attenuated influenza vaccine(LAIV) and inactivated influenza vaccine(IIV) is poorly explained by either single or composite immune responses to vaccination. Protective biomarkers were therefore studied in response to LAIV or IIV followed by LAIV challenge in children. Methods. Serum and mucosal responses to LAIV or IIV were analyzed using immunologic assays to assess both quantitative and functional responses. Cytokines and chemokines were measured in nasal washes collected before vaccination, on days 2, 4, and 7 after initial LAIV, and again after LAIV challenge using a 63-multiplex Luminex panel. Results. Patterns of immunity induced by LAIV and IIV were significantly different. Serum responses induced by IIV, including hemagglutination inhibition, did not correlate with detection or quantitation of LAIV on subsequent challenge. Modalities that induced sterilizing immunity seen after LAIV challenge could not be defined by any measurements of mucosal or serum antibodies induced by the initial LAIV immunization. No single cytokine or chemokine was predictive of protection. Conclusions. The mechanism of protective immunity observed after LAIV could not be defined, and traditional measurements of immunity to IIV did not correlate with protection against an LAIV challenge. PMID:27419180

  7. Immunization of Mice with Recombinant Brucella abortus Organic Hydroperoxide Resistance (Ohr) Protein Protects Against a Virulent Brucella abortus 544 Infection.

    PubMed

    Hop, Huynh Tan; Reyes, Alisha Wehdnesday Bernardo; Simborio, Hannah Leah Tadeja; Arayan, Lauren Togonon; Min, Won Gi; Lee, Hu Jang; Lee, Jin Ju; Chang, Hong Hee; Kim, Suk

    2016-01-01

    In this study, the Brucella abortus ohr gene coding for an organic hydroperoxide resistance protein (Ohr) was cloned into a maltose fusion protein expression system (pMAL), inserted into Escherichia coli, and purified, and its immunogenicity was evaluated by western blot analysis using Brucella-positive mouse sera. The purified recombinant Ohr (rOhr) was treated with adjuvant and injected intraperitoneally into BALB/c mice. A protective immune response analysis revealed that rOhr induced a significant increase in both the IgG1 and IgG2a titers, and IgG2a reached a higher level than IgG1 after the second and third immunizations. Additionally, immunization with rOhr induced high production of IFN-γ as well as proinflammatory cytokines such as TNF, MCP-1, IL-12p70, and IL-6, but a lesser amount of IL-10, suggesting that rOhr predominantly elicited a cell-mediated immune response. In addition, immunization with rOhr caused a significantly higher degree of protection against a virulent B. abortus infection compared with a positive control group consisting of mice immunized with maltose-binding protein. These findings showed that B. abortus rOhr was able to induce both humoral and cell-mediated immunity in mice, which suggested that this recombinant protein could be a potential vaccine candidate for animal brucellosis.

  8. A live attenuated vaccine prevents replication and transmission of H7N9 virus in mammals

    PubMed Central

    Kong, Huihui; Zhang, Qianyi; Gu, Chunyang; Shi, Jianzhong; Deng, Guohua; Ma, Shujie; Liu, Jinxiong; Chen, Pucheng; Guan, Yuntao; Jiang, Yongping; Chen, Hualan

    2015-01-01

    The continued spread of the newly emerged H7N9 viruses among poultry in China, together with the emergence of drug-resistant variants and the possibility of human-to-human transmission, has spurred attempts to develop an effective vaccine. An MF59-adjuvant H7N9 inactivated vaccine is reported to be well-tolerated and immunogenic in humans; however a study in ferrets indicated that while a single dose of the inactivated H7N9 vaccine reduced disease severity, it did not prevent virus replication and transmission. In this study, we used reverse genetics to produce a cold-adapted, live attenuated H7N9 vaccine (H7N9/AAca) that contains wild-type HA and NA genes from AH/1, and the backbone of the cold-adapted influenza H2N2 A/Ann Arbor/6/60 virus (AAca). H7N9/AAca was attenuated in mice and ferrets, and induced robust neutralizing antibody responses in rhesus mice, ferrets, and guinea pigs immunized once or twice intranasally. The animals immunized twice were completely protected from H7N9 virus challenge. Importantly, the animals vaccinated once were fully protected from transmission when exposed to or in contact with the H7N9 virus-inoculated animals. These results demonstrate that a cold-adapted H7N9 vaccine can prevent H7N9 virus transmission; they provide a compelling argument for further testing of this vaccine in human trials. PMID:26058711

  9. Extended Preclinical Safety, Efficacy and Stability Testing of a Live-attenuated Chikungunya Vaccine Candidate

    PubMed Central

    Plante, Kenneth S; Rossi, Shannan L.; Bergren, Nicholas A.; Seymour, Robert L.; Weaver, Scott C.

    2015-01-01

    We recently described a new, live-attenuated vaccine candidate for chikungunya (CHIK) fever, CHIKV/IRES. This vaccine was shown to be well attenuated, immunogenic and efficacious in protecting against CHIK virus (CHIKV) challenge of mice and nonhuman primates. To further evaluate its preclinical safety, we compared CHIKV/IRES distribution and viral loads in interferon-α/β receptor-incompetent A129 mice to another CHIK vaccine candidate, 181/clone25, which proved highly immunogenic but mildly reactive in human Phase I/II clinical trials. Compared to wild-type CHIK virus, (wt-CHIKV), both vaccines generated lower viral loads in a wide variety of tissues and organs, including the brain and leg muscle, but CHIKV/IRES exhibited marked restrictions in dissemination and viral loads compared to 181/clone25, and was never found outside the blood, spleen and muscle. Unlike wt-CHIKV, which caused disrupted splenic architecture and hepatic lesions, histopathological lesions were not observed in animals infected with either vaccine strain. To examine the stability of attenuation, both vaccines were passaged 5 times intracranially in infant A129 mice, then assessed for changes in virulence by comparing parental and passaged viruses for footpad swelling, weight stability and survival after subcutaneous infection. Whereas strain 181/clone25 p5 underwent a significant increase in virulence as measured by weight loss (from <10% to >30%) and mortality (from 0 to 100%), CHIKV/IRES underwent no detectible change in any measure of virulence (no significant weight loss and no mortality). These data indicate greater nonclinical safety of the CHIKV/IRES vaccine candidate compared to 181/clone25, further supporting its eligibility for human testing. PMID:26340754

  10. Duration of the protective immune response after prime and booster vaccination of yearlings with a live modified cold-adapted viral vaccine against equine influenza.

    PubMed

    Tabynov, K; Kydyrbayev, Zh; Ryskeldinova, Sh; Assanzhanova, N; Sansyzbay, A

    2014-05-23

    We previously created a live vaccine against equine influenza based the new reassortant cold-adapted (Ca) strain A/HK/Otar/6:2/2010. The live vaccine contains surface proteins (HA, NA) from the wild-type virus A/equine/Otar/764/2007 (Н3N8; American Lineage Florida Clade 2), and internal proteins (PB2, PB1, PA, NP, M, NS) from the attenuated Ca donor virus A/Hong Kong/1/68/162/35CA (H3N2). To determine the safety and duration of the protective immune responses, 90 yearlings were intranasally vaccinated in single mode, double mode at an interval of 42 days (10(7.0) EID50/animal for both vaccinations), or with PBS (control group). Ten animals from each group were challenged with the homologous wild-type virus A/equine/Otar/764/07 (Н3N8) at 1, 2, 3, 4, 5, 6, 9 and 12 months after vaccination. Similarly, 10 animals from each group were challenged with the heterologous wild-type virus A/equine/Sydney/2888-8/07 (Н3N8; American Lineage Florida Clade 1) 12 months after vaccination. The vaccine was completely safe, and single intranasal vaccination of yearlings was capable of inducing statistically significant (from P=0.03 to P<0.0001) clinical and virological protection against the homologous virus; however, only double mode vaccination generated significant (from P=0.02 to P<0.0001) protection against the heterologous virus at 12 months (observation period). Interestingly, this vaccine enables the differentiation of infected and vaccinated animals. On this basis of this study, we recommend double intranasal administration of this vaccine at an interval of 42 days in veterinary practice.

  11. Relaxation of purifying selection on the SAD lineage of live attenuated oral vaccines for rabies virus.

    PubMed

    Hughes, Austin L

    2009-09-01

    Analysis of patterns of nucleotide sequence diversity in wild-type rabies virus (RABV) genomes and in the SAD live attenuated oral vaccine lineage was used to test for the relaxation of purifying selection in the latter and provide evidence regarding the genomic regions where such relaxation of selection occurs. The wild-type sequences showed evidence of strong past and ongoing purifying selection both on nonsynonymous sites in coding regions and on non-coding regions, particularly the start, end and 5' UTR regions. SAD vaccine sequences showed a relaxation of purifying selection at nonsynonymous sites in coding regions, resulting a substantial number of amino acid sequence polymorphisms at sites that were invariant in the wild-type sequences. Moreover, SAD vaccine sequences showed high levels of mutation accumulation in the non-coding regions that were most conserved in the wild-type sequences. Understanding the biological effects of the unique mutations accumulated in the vaccine lineage is important because of their potential effects on antigenicity and effectiveness of the vaccine.

  12. Live attenuated B. pertussis as a single-dose nasal vaccine against whooping cough.

    PubMed

    Mielcarek, Nathalie; Debrie, Anne-Sophie; Raze, Dominique; Bertout, Julie; Rouanet, Carine; Younes, Amena Ben; Creusy, Colette; Engle, Jacquelyn; Goldman, William E; Locht, Camille

    2006-07-01

    Pertussis is still among the principal causes of death worldwide, and its incidence is increasing even in countries with high vaccine coverage. Although all age groups are susceptible, it is most severe in infants too young to be protected by currently available vaccines. To induce strong protective immunity in neonates, we have developed BPZE1, a live attenuated Bordetella pertussis strain to be given as a single-dose nasal vaccine in early life. BPZE1 was developed by the genetic inactivation or removal of three major toxins. In mice, BPZE1 was highly attenuated, yet able to colonize the respiratory tract and to induce strong protective immunity after a single nasal administration. Protection against B. pertussis was comparable to that induced by two injections of acellular vaccine (aPV) in adult mice, but was significantly better than two administrations of aPV in infant mice. Moreover, BPZE1 protected against Bordetella parapertussis infection, whereas aPV did not. BPZE1 is thus an attractive vaccine candidate to protect against whooping cough by nasal, needle-free administration early in life, possibly at birth.

  13. Tackling the issue of environmental survival of live Salmonella Typhimurium vaccines: deletion of the lon gene.

    PubMed

    Leyman, Bregje; Boyen, Filip; Van Parys, Alexander; Verbrugghe, Elin; Haesebrouck, Freddy; Pasmans, Frank

    2012-12-01

    Vaccination is an important measure to control Salmonella contamination in the meat production chain. A previous study showed that both the ΔrfaJ and ΔrfaL strains are suitable markers and allow serological differentiation of infected and vaccinated animals. The aim of this study was to verify whether deletion of the lon gene in a Salmonella Typhimurium ΔrfaJ marker strain resulted in decreased environmental survival. Our results indicate that deletion of the lon gene in the ΔrfaJ strain did not affect invasiveness in IPEC-J2 cells and resulted in an increased susceptibility to UV, disinfectants (such as hydrogen peroxide and tosylchloramide sodium) and citric acid. Immunization of pigs with inactivated ΔrfaJ or ΔlonΔrfaJ vaccines allowed differentiation of infected and vaccinated pigs. Furthermore, deletion of the lon gene did not reduce the protection conferred by live wild type or ΔrfaJ vaccines against subsequent challenge with a virulent Salmonella Typhimurium strain in BALB/c mice. Based on our results in mice, we conclude that deletion of lon in ΔrfaJ contributes to environmental safety of the ΔrfaJ DIVA strain.

  14. Assessment of local reaction to vaccines in live piglets with magnetic resonance imaging compared to histopathology.

    PubMed

    Bernau, Maren; Kremer, Prisca V; Kreuzer, Lena S; Emrich, Daniela; Pappenberger, Elke; Cussler, Klaus; Hoffmann, Andreas; Leipig, Miriam; Hermanns, Walter; Scholz, Armin Manfred

    2016-01-01

    The safety of veterinary vaccines is assessed in clinical trials in Europe. The assessment of the local tissue reaction to vaccination by magnetic resonance imaging (MRI) could reduce the number of animals needed because repeated examinations can be performed in the same animal over time. The present study compared the evaluation of local tissue reactions to vaccination using MRI in live pigs with histopathology of porcine tissue, the current gold standard in regulatory safety testing. Eight piglets each were administered one of two commercial vaccines into marked injection sites. All animals were sedated and scanned repeatedly by MRI using a contrast agent up to day 29 after vaccination. On day 29, the animals were euthanized and underwent a pathological examination. The MRI results were compared with the pathomorphological findings at the injection site by regression analysis. The MR images and the pathological examinations yielded matching results concerning the sizes of the affected tissue volumes or areas. The use of MRI for regulatory safety testing can reduce the number of animals needed to 8 per examination group. The volume of a local reaction and its progression over time can be evaluated and documented. If persistent lesions develop a final pathomorphological examination is needed to identify the kind and local distribution of the reaction.

  15. Live Attenuated B. pertussis as a Single-Dose Nasal Vaccine against Whooping Cough

    PubMed Central

    Mielcarek, Nathalie; Debrie, Anne-Sophie; Raze, Dominique; Bertout, Julie; Rouanet, Carine; Younes, Amena Ben; Creusy, Colette; Engle, Jacquelyn; Goldman, William E; Locht, Camille

    2006-01-01

    Pertussis is still among the principal causes of death worldwide, and its incidence is increasing even in countries with high vaccine coverage. Although all age groups are susceptible, it is most severe in infants too young to be protected by currently available vaccines. To induce strong protective immunity in neonates, we have developed BPZE1, a live attenuated Bordetella pertussis strain to be given as a single-dose nasal vaccine in early life. BPZE1 was developed by the genetic inactivation or removal of three major toxins. In mice, BPZE1 was highly attenuated, yet able to colonize the respiratory tract and to induce strong protective immunity after a single nasal administration. Protection against B. pertussis was comparable to that induced by two injections of acellular vaccine (aPV) in adult mice, but was significantly better than two administrations of aPV in infant mice. Moreover, BPZE1 protected against Bordetella parapertussis infection, whereas aPV did not. BPZE1 is thus an attractive vaccine candidate to protect against whooping cough by nasal, needle-free administration early in life, possibly at birth. PMID:16839199

  16. Safety and Immunogenicity of a Live-Attenuated Junin (Argentine Hemorrhagic Fever) Vaccine in Rhesus Macaques

    DTIC Science & Technology

    1993-01-01

    virus from animals in every dose group. vetted 1-2.5 weeks after initial virus recovery. That the viruses recovered were Junin virus is certain: all...wild-type strains (LI 1.25). When vivo neutralization and virus clearance are com- we used this system to examine viruses recovered plex and multi...Fredertcktfarniand Abstract. The safety and immunogenicity of Candid #1. a live-attenuated Junin- virus vaccine, were evaluated in rhesus macaques. Candid #1 was

  17. Use of an attenuated live Salmonella Typhimurium vaccine on three breeding pig units: A longitudinal observational field study.

    PubMed

    Davies, R; Gosling, R J; Wales, A D; Smith, R P

    2016-06-01

    The study examined the effects of a licensed live Salmonella Typhimurium vaccine, administered to sows and gilts on three commercial pig units experiencing clinical salmonellosis associated with S. Typhimurium or its monophasic variant. After vaccination, clinical salmonellosis resolved and shedding of S. Typhimurium declined markedly and persistently on all breeding or breeding-finishing units, during the one- to two-year monitoring period. On two finishing units supplied in part by one of the vaccinated herds, pigs from the vaccinated herd were less likely to shed Salmonella than those from non-vaccinating herds, and Salmonella counts in faeces were also lower from the vaccine-linked animals. Non-Typhimurium Salmonella serovars were isolated typically in fewer than 10% of samples, and showed no clear temporal changes in frequency. Vaccination of dams alone with S. Typhimurium was associated with reduced shedding of closely-related serovars among all age groups in this commercial setting.

  18. An overview of live attenuated recombinant pseudorabies viruses for use as novel vaccines.

    PubMed

    Dong, Bo; Zarlenga, Dante S; Ren, Xiaofeng

    2014-01-01

    Pseudorabies virus (PRV) is a double-stranded, DNA-based swine virus with a genome approximating 150 kb in size. PRV has many nonessential genes which can be replaced with genes encoding heterologous antigens but without deleterious effects on virus propagation. Recombinant PRVs expressing both native and foreign antigens are able to stimulate immune responses. In this paper, we review the current status of live attenuated recombinant PRVs and live PRV-based vector vaccines with potential for controlling viral infections in animals.

  19. Generation of a Live Attenuated Influenza Vaccine that Elicits Broad Protection in Mice and Ferrets.

    PubMed

    Wang, Lulan; Liu, Su-Yang; Chen, Hsiang-Wen; Xu, Juan; Chapon, Maxime; Zhang, Tao; Zhou, Fan; Wang, Yao E; Quanquin, Natalie; Wang, Guiqin; Tian, Xiaoli; He, Zhanlong; Liu, Longding; Yu, Wenhai; Sanchez, David Jesse; Liang, Yuying; Jiang, Taijiao; Modlin, Robert; Bloom, Barry R; Li, Qihan; Deng, Jane C; Zhou, Paul; Qin, F Xiao-Feng; Cheng, Genhong

    2017-03-08

    New influenza vaccines that provide effective and broad protection are desperately needed. Live attenuated viruses are attractive vaccine candidates because they can elicit both humoral and cellular immune responses. However, recent formulations of live attenuated influenza vaccines (LAIVs) have not been protective. We combined high-coverage transposon mutagenesis of influenza virus with a rapid high-throughput screening for attenuation to generate W7-791, a live attenuated mutant virus strain. W7-791 produced only a transient asymptomatic infection in adult and neonatal mice even at doses 100-fold higher than the LD50 of the parent strain. A single administration of W7-791 conferred full protection to mice against lethal challenge with H1N1, H3N2, and H5N1 strains, and improved viral clearance in ferrets. Adoptive transfer of T cells from W7-791-immunized mice conferred heterologous protection, indicating a role for T cell-mediated immunity. These studies present an LAIV development strategy to rapidly generate and screen entire libraries of viral clones.

  20. Development of Live-Attenuated Arenavirus Vaccines Based on Codon Deoptimization

    PubMed Central

    Cheng, Benson Yee Hin; Ortiz-Riaño, Emilio; Nogales, Aitor

    2015-01-01

    ABSTRACT Arenaviruses have a significant impact on public health and pose a credible biodefense threat, but the development of safe and effective arenavirus vaccines has remained elusive, and currently, no Food and Drug Administration (FDA)-licensed arenavirus vaccines are available. Here, we explored the use of a codon deoptimization (CD)-based approach as a novel strategy to develop live-attenuated arenavirus vaccines. We recoded the nucleoprotein (NP) of the prototypic arenavirus lymphocytic choriomeningitis virus (LCMV) with the least frequently used codons in mammalian cells, which caused lower LCMV NP expression levels in transfected cells that correlated with decreased NP activity in cell-based functional assays. We used reverse-genetics approaches to rescue a battery of recombinant LCMVs (rLCMVs) encoding CD NPs (rLCMV/NPCD) that showed attenuated growth kinetics in vitro. Moreover, experiments using the well-characterized mouse model of LCMV infection revealed that rLCMV/NPCD1 and rLCMV/NPCD2 were highly attenuated in vivo but, upon a single immunization, conferred complete protection against a subsequent lethal challenge with wild-type (WT) recombinant LCMV (rLCMV/WT). Both rLCMV/NPCD1 and rLCMV/NPCD2 were genetically and phenotypically stable during serial passages in FDA vaccine-approved Vero cells. These results provide proof of concept of the safety, efficacy, and stability of a CD-based approach for developing live-attenuated vaccine candidates against human-pathogenic arenaviruses. IMPORTANCE Several arenaviruses cause severe hemorrhagic fever in humans and pose a credible bioterrorism threat. Currently, no FDA-licensed vaccines are available to combat arenavirus infections, while antiarenaviral therapy is limited to the off-label use of ribavirin, which is only partially effective and is associated with side effects. Here, we describe the generation of recombinant versions of the prototypic arenavirus LCMV encoding codon-deoptimized viral

  1. Reversion of Cold-Adapted Live Attenuated Influenza Vaccine into a Pathogenic Virus

    PubMed Central

    Meliopoulos, Victoria A.; Wang, Wei; Lin, Xudong; Stucker, Karla M.; Halpin, Rebecca A.; Stockwell, Timothy B.; Schultz-Cherry, Stacey

    2016-01-01

    ABSTRACT The only licensed live attenuated influenza A virus vaccines (LAIVs) in the United States (FluMist) are created using internal protein-coding gene segments from the cold-adapted temperature-sensitive master donor virus A/Ann Arbor/6/1960 and HA/NA gene segments from circulating viruses. During serial passage of A/Ann Arbor/6/1960 at low temperatures to select the desired attenuating phenotypes, multiple cold-adaptive mutations and temperature-sensitive mutations arose. A substantial amount of scientific and clinical evidence has proven that FluMist is safe and effective. Nevertheless, no study has been conducted specifically to determine if the attenuating temperature-sensitive phenotype can revert and, if so, the types of substitutions that will emerge (i.e., compensatory substitutions versus reversion of existing attenuating mutations). Serial passage of the monovalent FluMist 2009 H1N1 pandemic vaccine at increasing temperatures in vitro generated a variant that replicated efficiently at higher temperatures. Sequencing of the variant identified seven nonsynonymous mutations, PB1-E51K, PB1-I171V, PA-N350K, PA-L366I, NP-N125Y, NP-V186I, and NS2-G63E. None occurred at positions previously reported to affect the temperature sensitivity of influenza A viruses. Synthetic genomics technology was used to synthesize the whole genome of the virus, and the roles of individual mutations were characterized by assessing their effects on RNA polymerase activity and virus replication kinetics at various temperatures. The revertant also regained virulence and caused significant disease in mice, with severity comparable to that caused by a wild-type 2009 H1N1 pandemic virus. IMPORTANCE The live attenuated influenza vaccine FluMist has been proven safe and effective and is widely used in the United States. The phenotype and genotype of the vaccine virus are believed to be very stable, and mutants that cause disease in animals or humans have never been reported. By

  2. Effect of size and temperature at vaccination on immunization and protection conferred by a live attenuated Francisella noatunensis immersion vaccine in red hybrid tilapia.

    PubMed

    Soto, Esteban; Brown, Nicholas; Gardenfors, Zackarias O; Yount, Shaun; Revan, Floyd; Francis, Stewart; Kearney, Michael T; Camus, Alvin

    2014-12-01

    Francisella noatunensis subsp. orientalis (Fno) is a pleomorphic, facultative intracellular, Gram-negative, emerging bacterial pathogen of marine and fresh water fish with worldwide distribution. In this study, the efficacy of an attenuated Fno intracellular growth locus C (iglC) mutant was evaluated for use as a live immersion vaccine, when administered to hybrid tilapia at two different stages of growth (5 g fry and 10 g fingerlings) and at two temperatures (25 °C and 30 °C). To determine vaccine efficacy, mortality, days to first death, and Fno genome equivalents (GE) in the spleens of survivors, as well as serum and mucus antibody levels, were evaluated after 30 d in fish challenged with a wild type virulent strain. Both size and temperature at vaccination played an important role in immunization and protection. Fry vaccinated at 25 °C were not protected when compared to non-vaccinated fry at 25 °C (p = 0.870). In contrast, 5 g fry vaccinated at 30 °C were significantly protected compared to non-vaccinated fry at 30 °C (p = 0.038). Although lower mortalities occurred, 10 g fingerlings vaccinated at 25 °C were not protected, compared to non-vaccinated fingerlings at 25 °C (p = 0.328), while, 10 g fingerlings vaccinated at 30 °C were significantly protected, compared to non-vaccinated fingerlings at 30 °C (p = 0.038). Additionally, overall mortality of 5 g fish was significantly higher than in 10 g fish. Mortality was also significantly higher in fish subjected to a 30 to 25 °C temperature change one week prior to challenge, than in fish maintained at the same temperature during vaccination and challenge. This information demonstrates that both temperature and size at vaccination are important factors when implementing immunization prophylaxis in cultured tilapia.

  3. Rapid and specific identification of Brucella abortus using the loop-mediated isothermal amplification (LAMP) assay.

    PubMed

    Kang, Sung-Il; Her, Moon; Kim, Ji-Yeon; Lee, Jin Ju; Lee, Kichan; Sung, So-Ra; Jung, Suk Chan

    2015-06-01

    A rapid and accurate diagnosis of brucellosis is required to reduce and prevent the spread of disease among animals and the risk of transfer to humans. In this study, a Brucella abortus-specific (Ba) LAMP assay was developed, that had six primers designed from the BruAb2_0168 region of chromosome I. The specificity of this LAMP assay was confirmed with Brucella reference strains, B. abortus vaccine strains, B. abortus isolates and phylogenetically or serologically related strains. The detection limit of target DNA was up to 20 fg/μl within 60 min. The sensitivity of the new LAMP assay was equal to or slightly higher than other PCR based assays. Moreover, this Ba-LAMP assay could specifically amplify all B. abortus biovars compared to previous PCR assays. To our knowledge, this is the first report of specific detection of B. abortus using a LAMP assay. The Ba-LAMP assay can offer a rapid, sensitive and accurate diagnosis of bovine brucellosis in the field.

  4. Antibody response in seropositive multiple sclerosis patients vaccinated with attenuated live varicella zoster virus

    PubMed Central

    Ross, RT; Dawood, MR; Cheang, Mary; Nicolle, Lindsay E

    1996-01-01

    OBJECTIVE: To determine the safety and effectiveness of live attenuated varicella zoster virus (VZV) vaccine (OKA/Merck) on 50 patients with chronic progressive multiple sclerosis (MS), based on the hypothesis that VZV might be the antigen or antigen mimic of MS plus the fact that repeated high antigen doses have produced ‘antigen paralysis’ in experimental allergic encephalomyelitis mice. DESIGN: Fifty patients were randomly selected without controls. They were assessed clinically at entry and on four other occasions over 14 months. Enhanced cranial magnetic resonance imaging (MRI) was performed at entry and at six and 12 months post entry. All were vaccinated after initial assessment and again six weeks later. SETTING: All clinical and laboratory assessments were performed at the Health Sciences Centre, Winnipeg, in the out-patient department. All MRI examinations were performed at the St Boniface General Hospital, Winnipeg, Manitoba. Both are tertiary care hospitals. POPULATION STUDIED: Fifty randomly selected patients with chronic progressive MS, age 18 to 60 years, and a disability status scale of 2.0 or greater were included. Forty-five patients completed the study. INTERVENTIONS: Two vaccinations with attenuated live VZV six weeks apart. RESULTS: All patients were VZV seropositive at entry and all showed an increased antibody level following vaccination. No one was harmed by the vaccine. There may have been some changes in the MS of 15 patients. CONCLUSIONS: It may be reasonable and safe to challenge the process of MS using large doses of the immunogenic proteins of the VZV to induce ‘immune paralysis’. PMID:22514454

  5. Live virus vaccines based on a yellow fever vaccine backbone: standardized template with key considerations for a risk/benefit assessment.

    PubMed

    Monath, Thomas P; Seligman, Stephen J; Robertson, James S; Guy, Bruno; Hayes, Edward B; Condit, Richard C; Excler, Jean Louis; Mac, Lisa Marie; Carbery, Baevin; Chen, Robert T

    2015-01-01

    The Brighton Collaboration Viral Vector Vaccines Safety Working Group (V3SWG) was formed to evaluate the safety of live, recombinant viral vaccines incorporating genes from heterologous viruses inserted into the backbone of another virus (so-called "chimeric virus vaccines"). Many viral vector vaccines are in advanced clinical trials. The first such vaccine to be approved for marketing (to date in Australia, Thailand, Malaysia, and the Philippines) is a vaccine against the flavivirus, Japanese encephalitis (JE), which employs a licensed vaccine (yellow fever 17D) as a vector. In this vaccine, two envelope proteins (prM-E) of YF 17D virus were exchanged for the corresponding genes of JE virus, with additional attenuating mutations incorporated into the JE gene inserts. Similar vaccines have been constructed by inserting prM-E genes of dengue and West Nile into YF 17D virus and are in late stage clinical studies. The dengue vaccine is, however, more complex in that it requires a mixture of four live vectors each expressing one of the four dengue serotypes. This vaccine has been evaluated in multiple clinical trials. No significant safety concerns have been found. The Phase 3 trials met their endpoints in terms of overall reduction of confirmed dengue fever, and, most importantly a significant reduction in severe dengue and hospitalization due to dengue. However, based on results that have been published so far, efficacy in preventing serotype 2 infection is less than that for the other three serotypes. In the development of these chimeric vaccines, an important series of comparative studies of safety and efficacy were made using the parental YF 17D vaccine virus as a benchmark. In this paper, we use a standardized template describing the key characteristics of the novel flavivirus vaccine vectors, in comparison to the parental YF 17D vaccine. The template facilitates scientific discourse among key stakeholders by increasing the transparency and comparability of

  6. Serologic response of roosters to gradient dosage levels of a commercially available live F strain-derived Mycoplasma gallisepticum vaccine over time

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Spray application is a commonly used time- and labor-efficient means to deliver live Mycoplasma gallisepticum (MG) vaccine to laying hens in commercial production facilities. The dosage of vaccine received by spray vaccinated birds can vary due to variation in the spray plume and vaccine suspension...

  7. Clinical Trial of an Oral Live Shigella sonnei Vaccine Candidate, WRSS1, in Thai Adults

    PubMed Central

    Islam, Dilara; Chamnanchanunt, Supat; Ruamsap, Nattaya; Khantapura, Patchariya; Kaewkungwal, Jaranit; Kittitrakul, Chatporn; Luvira, Viravarn; Dhitavat, Jittima; Venkatesan, Malabi M.; Mason, Carl J.; Bodhidatta, Ladaporn

    2016-01-01

    Live attenuated Shigella sonnei vaccine candidate WRSS1, previously tested in U.S. and Israeli volunteers, was evaluated in a population of adult Thai volunteers in which the organism is endemic. In a randomized placebo-controlled, double-blind design, inpatient participants received a single oral dose of 1.6 × 104 CFU of WRSS1. The vaccine was generally well tolerated, with equal numbers of vaccinees and placebo controls showing mild symptoms. Only 3 of 13 vaccinees (23%) had culture-positive stools, while a total of 9 vaccinees were positive by PCR. Lack of vaccine shedding in volunteers correlated with lack of clinical symptoms and immune responses, just as the duration of fecal shedding correlated directly with stronger immune responses. Two months following immunization, 10 vaccinees and 10 newly recruited naive controls received a challenge dose of 1,670 CFU of virulent S. sonnei strain 53G. This dose had previously demonstrated a 75% attack rate for dysentery in Thai volunteers. However, in this study the attack rate for dysentery in naive controls after challenge was 20%. Based on clinical record summaries, 3 vaccinees and 5 naive controls experienced clinically relevant illness (diarrhea/dysentery/fever/shigellosis), and a 40% vaccine efficacy was calculated. When these data are compared to those for the performance of this vaccine candidate in more naive populations, it is clear that a single oral dose of WRSS1 at 104 CFU failed to achieve its full potential in a population in which the organism is endemic. Higher doses and/or repeated immunizations may contribute to improved vaccine shedding and consequent elevation of protective immune responses in a population in which the organism is endemic. (The study has been registered at ClinicalTrials.gov under registration no. NCT01080716.) PMID:27146000

  8. Vaccination with a modified-live bovine viral diarrhea virus (BVDV) type 1a vaccine completely protected calves against challenge with BVDV type 1b strains.

    PubMed

    Xue, Wenzhi; Mattick, Debra; Smith, Linda; Umbaugh, Jerry; Trigo, Emilio

    2010-12-10

    Vaccination plays a significant role in the control of bovine viral diarrhea virus (BVDV) infection and spread. Recent studies revealed that type 1b is the predominant BVDV type 1 subgenotype, representing more than 75% of field isolates of BVDV-1. However, nearly all current, commercially available BVDV type 1 vaccines contain BVDV-1a strains. Previous studies have indicated that anti-BVDV sera, induced by BVDV-1a viruses, show less neutralization activity to BVDV-1b isolates than type 1a. Therefore, it is critically important to evaluate BVDV-1a vaccines in their ability to prevent BVDV-1b infection in calves. In current studies, calves were vaccinated subcutaneously, intradermally or intranasally with a single dose of a multivalent, modified-live viral vaccine containing a BVDV-1a strain, and were challenged with differing BVDV-1b strains to determine the efficacy and duration of immunity of the vaccine against these heterologous virus strains. Vaccinated calves, in all administration routes, were protected from respiratory disease caused by the BVDV-1b viruses, as indicated by significantly fewer clinical signs, lower rectal temperatures, reduced viral shedding and greater white blood cell counts than non-vaccinated control animals. The BVDV-1a vaccine elicited efficacious protection in calves against each BVDV-1b challenge strain, with a duration of immunity of at least 6 months.

  9. Biomarkers of safety and immune protection for genetically modified live attenuated leishmania vaccines against visceral leishmaniasis - discovery and implications.

    PubMed

    Gannavaram, Sreenivas; Dey, Ranadhir; Avishek, Kumar; Selvapandiyan, Angamuthu; Salotra, Poonam; Nakhasi, Hira L

    2014-01-01

    Despite intense efforts there is no safe and efficacious vaccine against visceral leishmaniasis, which is fatal and endemic in many tropical countries. A major shortcoming in the vaccine development against blood-borne parasitic agents such as Leishmania is the inadequate predictive power of the early immune responses mounted in the host against the experimental vaccines. Often immune correlates derived from in-bred animal models do not yield immune markers of protection that can be readily extrapolated to humans. The limited efficacy of vaccines based on DNA, subunit, heat killed parasites has led to the realization that acquisition of durable immunity against the protozoan parasites requires a controlled infection with a live attenuated organism. Recent success of irradiated malaria parasites as a vaccine candidate further strengthens this approach to vaccination. We developed several gene deletion mutants in Leishmania donovani as potential live attenuated vaccines and reported extensively on the immunogenicity of LdCentrin1 deleted mutant in mice, hamsters, and dogs. Additional limited studies using genetically modified live attenuated Leishmania parasites as vaccine candidates have been reported. However, for the live attenuated parasite vaccines, the primary barrier against widespread use remains the absence of clear biomarkers associated with protection and safety. Recent studies in evaluation of vaccines, e.g., influenza and yellow fever vaccines, using systems biology tools demonstrated the power of such strategies in understanding the immunological mechanisms that underpin a protective phenotype. Applying similar tools in isolated human tissues such as PBMCs from healthy individuals infected with live attenuated parasites such as LdCen(-/-) in vitro followed by human microarray hybridization experiments will enable us to understand how early vaccine-induced gene expression profiles and the associated immune responses are coordinately regulated in normal

  10. Vaccination status of people living with HIV/AIDS in outpatient care in Fortaleza, Ceará, Brazil.

    PubMed

    Cunha, Gilmara Holanda da; Galvão, Marli Teresinha Gimeniz; Medeiros, Camila Martins de; Rocha, Ryvanne Paulino; Lima, Maria Amanda Correia; Fechine, Francisco Vagnaldo

    2016-01-01

    Antiretroviral therapy has increased the survival of patients with HIV/AIDS, thus necessitating health promotion practice with immunization. Vaccines are critical components for protecting people living with HIV/AIDS (PLWHA). The purpose of study was to analyze the vaccination status of PLWHA in outpatient care in Fortaleza, Ceará, Brazil. Cross-sectional study performed from June 2014 to June 2015. The screening was done with patients in antiretroviral therapy, 420 patients underwent screening, but only 99 met the inclusion criteria. Data were collected for interviews using forms to characterize sociodemographic, clinical and vaccination situations. Only 14 patients had complete vaccination schedules. The most used vaccines were hepatitis B, influenza vaccine and 23-valent pneumococcal. There was no difference between men and women regarding the proportion of PLWHA with full vaccination schedule or between sex, skin color, marital status, sexual orientation, religion or occupational status. There was no difference between having or not having a complete vaccination schedule and age, years of education, family income or number of hospitalizations. CD4+ T-cells count of patients with incomplete immunization was lower than patients with complete immunization. Health education strategies can be done individually or in groups to explain the importance of vaccination and to remind about doses to be administered. Most patients did not have proper adherence to vaccination schedules, especially due to lack of guidance. Results implied that education in health is important for vaccination adhesion, knowledge of adverse events and continuation of schemes.

  11. A Review of OIE Country Status Recovery Using Vaccinate-to-Live Versus Vaccinate-to-Die Foot-and-Mouth Disease Response Policies II: Waiting Periods After Emergency Vaccination in FMD Free Countries.

    PubMed

    Geale, D W; Barnett, P V; Clarke, G W; Davis, J; Kasari, T R

    2015-08-01

    For countries with OIE status, FMD free country where vaccination is not practised, vaccinate-to-live policies have a significant economic disincentive as the trade restriction waiting period is double that of vaccinate-to-die policies. The disposal of healthy vaccinated animals strictly for the purpose of regaining markets with debatable scientific justification is a global concern. The feasibility of aligning the waiting periods to facilitate vaccinate-to-live is explored. The first article of this two-part review (Barnett et al., 2015) explored the qualities of higher potency Foot-and-Mouth Disease (FMD) vaccines, performance of differentiating infected from vaccinated animals (DIVA) diagnostic assays particularly in vaccinates and carriers, as well as aspects of current limitations of post-outbreak surveillance. Here, the history behind the OIE waiting periods for FMD free status is reviewed as well as whether the risk of vaccinated animals and their subsequent products differ appreciably at 3 versus 6 months. It is concluded that alignment is feasible for vaccinate-to-live using higher potency FMD vaccines within the current OIE waiting period framework of 3 and 6 months blocks of time. These waiting periods reflect precedence, historical practicalities and considered expert opinion rather than a specific scientific rationale. The future lies in updated epidemiological and diagnostic technology to establish an acceptable level of statistical certainty for surveillance or target probability of freedom of FMDV (infection or circulation) not time restricted waiting periods. The OIE Terrestrial Code limits trade from a FMD free country where vaccination is not practiced to animal products and live non-vaccinated animals. The risk of FMDV in products derived from higher potency vaccinated animals is appreciably less than for countries with infected FMD status or even from a FMD free country where vaccination is practised for which the Code has Articles with

  12. Live Virus Vaccines Based on a Yellow Fever Vaccine Backbone: Standardized Template with Key Considerations for a Risk/Benefit Assessment*

    PubMed Central

    Monath, Thomas P.; Seligman, Stephen J.; Robertson, James S.; Guy, Bruno; Hayes, Edward B.; Condit, Richard C.; Excler, Jean Louis; Mac, Lisa Marie; Carbery, Baevin; Chen, Robert T

    2015-01-01

    The Brighton Collaboration Viral Vector Vaccines Safety Working Group (V3SWG) was formed to evaluate the safety of live, recombinant viral vaccines incorporating genes from heterologous viruses inserted into the backbone of another virus (so-called “chimeric virus vaccines”). Many viral vector vaccines are in advanced clinical trials. The first such vaccine to be approved for marketing (to date in Australia, Thailand, Malaysia, and the Philippines) is a vaccine against the flavivirus Japanese encephalitis (JE), which employs a licensed vaccine (yellow fever 17D) as a vector. In this vaccine, two envelope proteins (prM-E) of YF 17D virus were replaced by the corresponding genes of JE virus, with additional attenuating mutations incorporated into the JE gene inserts. Similar vaccines have been constructed by inserting prM-E genes of dengue and West Nile into YF 17D virus and are in late stage clinical studies. The dengue vaccine is, however, more complex in that it requires a mixture of four live vectors each expressing one of the four dengue serotypes. This vaccine has been evaluated in multiple clinical trials. No significant safety concerns have been found. The Phase 3 trials met their endpoints in terms of overall reduction of confirmed dengue fever, and, most importantly a significant reduction in severe dengue and hospitalization due to dengue. However, based on results that have been published so far, efficacy in preventing serotype 2 infection is less than that for the other three serotypes. In the development of these chimeric vaccines, an important series of comparative studies of safety and efficacy were made using the parental YF 17D vaccine virus as a benchmark. In this paper, we use a standardized template describing the key characteristics of the novel flavivirus vaccine vectors, in comparison to the parental YF 17D vaccine. The template facilitates scientific discourse among key stakeholders by increasing the transparency and comparability of

  13. A Reverse Genetics Approach for the Design of Methyltransferase-Defective Live Attenuated Avian Metapneumovirus Vaccines.

    PubMed

    Zhang, Yu; Sun, Jing; Wei, Yongwei; Li, Jianrong

    2016-01-01

    Avian metapneumovirus (aMPV), also known as avian pneumovirus or turkey rhinotracheitis virus, is the causative agent of turkey rhinotracheitis and is associated with swollen head syndrome in chickens. aMPV belongs to the family Paramyxoviridae which includes many important human pathogens such as human respiratory syncytial virus (RSV), human metapneumovirus (hMPV), and human parainfluenza virus type 3 (PIV3). The family also includes highly lethal emerging pathogens such as Nipah virus and Hendra virus, as well as agriculturally important viruses such as Newcastle disease virus (NDV). For many of these viruses, there is no effective vaccine. Here, we describe a reverse genetics approach to develop live attenuated aMPV vaccines by inhibiting the viral mRNA cap methyltransferase. The viral mRNA cap methyltransferase is an excellent target for the attenuation of paramyxoviruses because it plays essential roles in mRNA stability, efficient viral protein translation and innate immunity. We have described in detail the materials and methods used to generate recombinant aMPVs that lack viral mRNA cap methyltransferase activity. We have also provided methods to evaluate the genetic stability, pathogenesis, and immunogenicity of live aMPV vaccine candidates in turkeys.

  14. Recurrent 6th nerve palsy in a child following different live attenuated vaccines: case report

    PubMed Central

    2012-01-01

    Background Recurrent benign 6th nerve palsy in the paediatric age group is uncommon, but has been described following viral and bacterial infections. It has also been temporally associated with immunization, but has not been previously described following two different live attenuated vaccines. Case presentation A case is presented of a 12 month old Caucasian boy with recurrent benign 6th nerve palsy following measles-mumps-rubella and varicella vaccines, given on separate occasions with complete recovery following each episode. No alternate underlying etiology was identified despite extensive investigations and review. Conclusions The majority of benign 6th nerve palsies do not have a sinister cause and have an excellent prognosis, with recovery expected in most cases. The exact pathophysiology is unknown, although hypotheses including autoimmune mechanisms and direct viral invasion could explain the pathophysiology behind immunization related nerve palsies. It is important to rule out other aetiologies with thorough history, physical examination and investigations. There is limited information in the literature regarding the safety of a repeat dose of a live vaccine in this setting. Future immunizations should be considered on a case-by-case basis. PMID:22545865

  15. Protection from SARS coronavirus conferred by live measles vaccine expressing the spike glycoprotein.

    PubMed

    Escriou, Nicolas; Callendret, Benoît; Lorin, Valérie; Combredet, Chantal; Marianneau, Philippe; Février, Michèle; Tangy, Frédéric

    2014-03-01

    The recent identification of a novel human coronavirus responsible of a SARS-like illness in the Middle-East a decade after the SARS pandemic, demonstrates that reemergence of a SARS-like coronavirus from an animal reservoir remains a credible threat. Because SARS is contracted by aerosolized contamination of the respiratory tract, a vaccine inducing mucosal long-term protection would be an asset to control new epidemics. To this aim, we generated live attenuated recombinant measles vaccine (MV) candidates expressing either the membrane-anchored SARS-CoV spike (S) protein or its secreted soluble ectodomain (Ssol). In mice susceptible to measles virus, recombinant MV expressing the anchored full-length S induced the highest titers of neutralizing antibodies and fully protected immunized animals from intranasal infectious challenge with SARS-CoV. As compared to immunization with adjuvanted recombinant Ssol protein, recombinant MV induced stronger and Th1-biased responses, a hallmark of live attenuated viruses and a highly desirable feature for an antiviral vaccine.

  16. Lactic acid bacteria--20 years exploring their potential as live vectors for mucosal vaccination.

    PubMed

    Wyszyńska, Agnieszka; Kobierecka, Patrycja; Bardowski, Jacek; Jagusztyn-Krynicka, Elżbieta Katarzyna

    2015-04-01

    Lactic acid bacteria (LAB) are a diverse group of Gram-positive, nonsporulating, low G + C content bacteria. Many of them have been given generally regarded as safe status. Over the past two decades, intensive genetic and molecular research carried out on LAB, mainly Lactococcus lactis and some species of the Lactobacillus genus, has revealed new, potential biomedical LAB applications, including the use of LAB as adjuvants, immunostimulators, or therapeutic drug delivery systems, or as factories to produce therapeutic molecules. LAB enable immunization via the mucosal route, which increases effectiveness against pathogens that use the mucosa as the major route of entry into the human body. In this review, we concentrate on the encouraging application of Lactococcus and Lactobacillus genera for the development of live mucosal vaccines. First, we present the progress that has recently been made in the field of developing tools for LAB genetic manipulations, which has resulted in the successful expression of many bacterial, parasitic, and viral antigens in LAB strains. Next, we discuss the factors influencing the efficacy of the constructed vaccine prototypes that have been tested in various animal models. Apart from the research focused on an application of live LABs as carriers of foreign antigens, a lot of work has been recently done on the potential usage of nonliving, nonrecombinant L. lactis designated as Gram-positive enhancer matrix (GEM), as a delivery system for mucosal vaccination. The advantages and disadvantages of both strategies are also presented.

  17. A laminated polymer film formulation for enteric delivery of live vaccine and probiotic bacteria.

    PubMed

    de Barros, João M S; Scherer, Timothy; Charalampopoulos, Dimitrios; Khutoryanskiy, Vitaliy V; Edwards, Alexander D

    2014-07-01

    Live bacterial cells (LBCs) are administered orally as attenuated vaccines to deliver biopharmaceutical agents and as probiotics to improve gastrointestinal (GI) health. However, LBCs present unique formulation challenges and must survive GI antimicrobial defenses including gastric acid after administration. We present a simple new formulation concept, termed polymer film laminate (PFL). LBCs are ambient dried onto cast acid-resistant enteric polymer films that are then laminated together to produce a solid oral dosage form. LBC of a model live bacterial vaccine and a probiotic were dried directly onto a cast film of enteric polymer. The effectiveness at protecting dried cells in a simulated gastric fluid (SGF, pH 2.0) depended on the composition of enteric polymer film used, with a blend of ethylcellulose plus Eudragit L100 55 providing greater protection from acid than Eudragit alone. However, although PFL made from blended polymer films completely released low-molecular-weight dye into intestinal conditions (pH 7.0), they failed to release LBCs. In contrast, PFL made from Eudragit alone successfully protected dried probiotic or vaccine LBC from SGF for 2 h, and subsequently released all viable cells within 60 min of transfer into simulated intestinal fluid. Release kinetics could be controlled by modifying the lamination method.

  18. Development of live-attenuated arenavirus vaccines based on codon deoptimization of the viral glycoprotein.

    PubMed

    Cheng, Benson Y H; Nogales, Aitor; de la Torre, Juan Carlos; Martínez-Sobrido, Luis

    2017-01-15

    Several arenaviruses, chiefly Lassa (LASV) in West Africa, cause hemorrhagic fever (HF) disease in humans and pose important public health problems in their endemic regions. To date, there are no FDA-approved arenavirus vaccines and current anti-arenaviral therapy is limited to the use of ribavirin that has very limited efficacy. In this work we document that a recombinant prototypic arenavirus lymphocytic choriomeningitis virus (LCMV) with a codon deoptimized (CD) surface glycoprotein (GP), rLCMV/CD, exhibited wild type (WT)-like growth properties in cultured cells despite barely detectable GP expression levels in rLCMV/CD-infected cells. Importantly, rLCMV/CD was highly attenuated in vivo but able to induce complete protection against a subsequent lethal challenge with rLCMV/WT. Our findings support the feasibility of implementing an arenavirus GP CD-based approach for the development of safe and effective live-attenuated vaccines (LAVs) to combat diseases caused by human pathogenic arenaviruses.

  19. The yellow fever 17D virus as a platform for new live attenuated vaccines.

    PubMed

    Bonaldo, Myrna C; Sequeira, Patrícia C; Galler, Ricardo

    2014-01-01

    The live-attenuated yellow fever 17D virus is one of the most outstanding human vaccines ever developed. It induces efficacious immune responses at a low production cost with a well-established manufacture process. These advantages make the YF17D virus attractive as a vector for the development of new vaccines. At the beginning of vector development studies, YF17D was genetically manipulated to express other flavivirus prM and E proteins, components of the viral envelope. While these 17D recombinants are based on the substitution of equivalent YF17D genes, other antigens from unrelated pathogens have also been successfully expressed and delivered by recombinant YF17D viruses employing alternative strategies for genetic manipulation of the YF17D genome. Herein, we discuss these strategies in terms of possibilities of single epitope or larger sequence expression and the main properties of these replication-competent viral platforms.

  20. Models derived from in vitro analyses of spleen, liver, and lung leukocyte functions predict vaccine efficacy against the Francisella tularensis Live Vaccine Strain (LVS).

    PubMed

    De Pascalis, Roberto; Chou, Alicia Y; Ryden, Patrik; Kennett, Nikki J; Sjöstedt, Anders; Elkins, Karen L

    2014-04-08

    Currently, there are no licensed vaccines and no correlates of protection against Francisella tularensis, which causes tularemia. We recently demonstrated that measuring in vitro control of intramacrophage bacterial growth by murine F. tularensis-immune splenocytes, as well as transcriptional analyses, discriminated Francisella vaccines of different efficacies. Further, we identified potential correlates of protection against systemic challenge. Here, we extended this approach by studying leukocytes derived from lungs and livers of mice immunized by parenteral and respiratory routes with F. tularensis vaccines. Liver and lung leukocytes derived from intradermally and intranasally vaccinated mice controlled in vitro Francisella Live Vaccine Strain (LVS) intramacrophage replication in patterns similar to those of splenocytes. Gene expression analyses of potential correlates also revealed similar patterns in liver cells and splenocytes. In some cases (e.g., tumor necrosis factor alpha [TNF-α], interleukin 22 [IL-22], and granulocyte-macrophage colony-stimulating factor [GM-CSF]), liver cells exhibited even higher relative gene expression, whereas fewer genes exhibited differential expression in lung cells. In contrast with their strong ability to control LVS replication, splenocytes from intranasally vaccinated mice expressed few genes with a hierarchy of expression similar to that of splenocytes from intradermally vaccinated mice. Thus, the relative levels of gene expression vary between cell types from different organs and by vaccination route. Most importantly, because studies comparing cell sources and routes of vaccination supported the predictive validity of this coculture and gene quantification approach, we combined in vitro LVS replication with gene expression data to develop analytical models that discriminated between vaccine groups and successfully predicted the degree of vaccine efficacy. Thus, this strategy remains a promising means of identifying and

  1. Innate and adaptive immune control of genetically engineered live-attenuated arenavirus vaccine prototypes.

    PubMed

    Pinschewer, Daniel D; Flatz, Lukas; Steinborn, Ralf; Horvath, Edit; Fernandez, Marylise; Lutz, Hans; Suter, Mark; Bergthaler, Andreas

    2010-09-01

    Arenaviruses such as Lassa virus (LASV) cause significant morbidity and mortality in endemic areas. Using a glycoprotein (GP) exchange strategy, we have recently developed live-attenuated arenavirus vaccine prototypes (rLCMV/VSVG) based on lymphocytic choriomeningitis virus (LCMV), a close relative of LASV. rLCMV/VSVG induced long-term CD8(+) T cell immunity against wild-type virus challenge and exhibited a stably attenuated phenotype in vivo. Here we elucidated the innate and adaptive immune requirements for the control of rLCMV/VSVG. Infection of RAG(-/-) mice resulted in persisting viral RNA in blood but not in overt viremia. The latter was only found in mice lacking both RAG and IFN type I receptor. Conversely, absence of IFN type II signaling or NK cells on an RAG-deficient background had only minor effects on vaccine virus load or none at all. rLCMV/VSVG infection of wild-type mice induced less type I IFN than did wild-type LCMV, and type I as well as type II IFNs were dispensable for the induction of virus-specific memory CD8 T cells and virus-neutralizing antibodies by rLCMV/VSVG. In conclusion, the adaptive immune systems are essential for elimination of rLCMV/VSVG, and type I but not type II IFN plays a major contributive role in lowering rLCMV/VSVG loads in vivo, attesting to the attenuation profile of the vaccine. Nevertheless, IFNs are not required for the induction of potent vaccine responses. These results provide a better understanding of the immunobiology of rLCMV/VSVG and will contribute to the further development of GP exchange vaccines for combating arenaviral hemorrhagic fevers.

  2. Comparative Immunogenicities of Frozen and Refrigerated Formulations of Live Attenuated Influenza Vaccine in Healthy Subjects▿

    PubMed Central

    Block, Stan L.; Reisinger, Keith S.; Hultquist, Micki; Walker, Robert E.

    2007-01-01

    The frozen version of live attenuated influenza vaccine (LAIV; FluMist) was compared with a newly licensed, refrigerated formulation, the cold-adapted influenza vaccine, trivalent (CAIV-T), for their immunogenicity, safety, and tolerability in healthy subjects 5 to 49 years of age. Eligible subjects were randomized 1:1 to receive CAIV-T or frozen LAIV. Subjects 5 to 8 years of age received two doses of vaccine 46 to 60 days apart; subjects 9 to 49 years of age received one dose of vaccine. Equivalent immunogenicities were defined as serum hemagglutination inhibition (HAI) geometric mean titer (GMT) ratios >0.5 and <2.0 for each of the three vaccine-specific strains. A total of 376 subjects 5 to 8 years of age and 566 subjects 9 to 49 years of age were evaluable. Postvaccination HAI GMT ratios were equivalent for CAIV-T and LAIV. The GMT ratios of CAIV-T/LAIV for the H1N1, H3N2, and B strains were 1.24, 1.02, and 1.00, respectively, for the 5- to 8-year-old age group and 1.14, 1.12, and 0.96, respectively, for the 9- to 49-year-old age group. Seroresponse/seroconversion rates (fourfold or greater rise) were similar in both age groups for each of the three vaccine strains. Within 28 days, the most frequent reactogenicity event in the CAIV-T and LAIV groups was runny nose/nasal congestion, which occurred at higher rates after dose 1 (44% and 42%, respectively) than after dose 2 (41% and 29%, respectively) in the 5- to 8-year-old group. Otherwise, the rates of adverse events (AEs) were similar between the treatment groups and the two age cohorts, with no serious AEs related to the study vaccines. The immunogenicities, reactogenicity events, and AEs were comparable for refrigerated CAIV-T and frozen LAIV. PMID:17724151

  3. Characterisation of a live Salmonella vaccine stably expressing the Mycobacterium tuberculosis Ag85B–ESAT6 fusion protein

    PubMed Central

    Hall, Lindsay J.; Clare, Simon; Pickard, Derek; Clark, Simon O.; Kelly, Dominic L.F.; Ghany, Moataz Abd El; Hale, Christine; Dietrich, Jes; Andersen, Peter; Marsh, Philip D.; Dougan, Gordon

    2009-01-01

    A recombinant Salmonella enterica serovar Typhimurium (S. Typhimurium) vaccine strain was constructed that stably expressed the Mycobacterium tuberculosis fusion antigen Ag85B–ESAT6 from the chromosome. Live oral vaccination of mice with the Salmonella/Ag85B–ESAT6 strain generated a potent anti-Ag85B–ESAT6 TH1 response with high antibody titres with a IgG2a-bias and significant IFN-γ production lasting over a 120-day period. When mice primed with the Salmonella/Ag85B–ESAT6 vaccine were mucosally boosted with the Ag85B–ESAT6 antigen and adjuvant the IFN-γ responses increased markedly. To determine the protective efficacy of this vaccine strain, guinea pigs were immunised and followed for a 30-week period after aerosol challenge with M. tuberculosis. The heterologous prime-boost strategy of live Salmonella vaccine followed by a systemic boost of antigen and adjuvant reduced the levels of M. tuberculosis bacteria in the lungs and spleen to the same extent as BCG. Additionally, this vaccination regimen was observed to be statistically equivalent in terms of protection to immunisation with BCG. Thus, live oral priming with the recombinant Salmonella/Ag85B–ESAT6 and boosting with Ag85B–ESAT6 plus the adjuvant LTK63 represents an effective mucosal vaccination regimen. PMID:19755145

  4. Brucella suis strain 2 vaccine is safe and protective against heterologous Brucella spp. infections.

    PubMed

    Zhu, Liangquan; Feng, Yu; Zhang, Ge; Jiang, Hui; Zhang, Zhen; Wang, Nan; Ding, Jiabo; Suo, Xun

    2016-01-12

    Brucellosis is a wide spread zoonotic disease that causes abortion and infertility in mammals and leads to debilitating, febrile illness in humans. Brucella abortus, Brucella melitensis and Brucella suis are the major pathogenic species to humans. Vaccination with live attenuated B. suis strain 2 (S2) vaccine is an essential and critical component in the control of brucellosis in China. The S2 vaccine is very effective in preventing brucellosis in goats, sheep, cattle and swine. However, there are still debates outside of China whether the S2 vaccine is able to provide protection against heterologous virulent Brucella species. We investigated the residual virulence, immunogenicity and protective efficacy of the S2 vaccine in BALB/c mice by determining bacteria persistence in spleen, serum antibody response, cellular immune response and protection against a heterologous virulent challenge. The S2 vaccine was of low virulence as there were no bacteria recovered in spleen four weeks post vaccination. The vaccinated mice developed Brucella-specific IgG in 2-3 weeks, and a burst production of IFN-γ at one week as well as a two-fold increase in TNF-α production. The S2 vaccine protected mice from a virulent challenge by B. melitensis M28, B. abortus 2308 and B. suis S1330, and the S2 vaccinated mice did not develop any clinical signs or tissue damage. Our study demonstrated that the S2 vaccine is of low virulence, stimulates good humoral and cellular immunity and protects animals against infection by heterologous, virulent Brucella species.

  5. The bovine immune response to Brucella abortus I. A water soluble antigen precipitated by sera of some naturally infected cattle.

    PubMed Central

    Stemshorn, B; Nielsen, K

    1977-01-01

    Selected sera from cattle naturally infected with Brucella abortus precipitate water soluble antigens extracted by sonication from B. abortus. One of these antigens resembles antigen E (Baughn and Freeman) as it is excluded from Sephadex G-200 gels, migrates anodally when electrophoresed at pH 8.6, resists heating at 100 degrees C for ten minutes and appears to be susceptible to papain digestion. Precipitins specific for this antigen remained in sera from which all detectable Brucella agglutinating antibody had been removed by adsorption with live or heat killed B. abortus. The antigen has been extracted from smooth and rough strains of B abortus. Precipitins specific for this antigen have been detected in antisera produced against Brucella canis. Images Fig. 1. Fig. 2. Fig. 3. Fig. 4. PMID:405088

  6. Long-term safety assessment of live attenuated tetravalent dengue vaccines: deliberations from a WHO technical consultation.

    PubMed

    Bentsi-Enchill, Adwoa D; Schmitz, Julia; Edelman, Robert; Durbin, Anna; Roehrig, John T; Smith, Peter G; Hombach, Joachim; Farrar, Jeremy

    2013-05-28

    Dengue is a rapidly growing public health threat with approximately 2.5 billion people estimated to be at risk. Several vaccine candidates are at various stages of pre-clinical and clinical development. Thus far, live dengue vaccine candidates have been administered to several thousands of volunteers and were well-tolerated, with minimal short-term safety effects reported in Phase I and Phase II clinical trials. Based on the natural history of dengue, a theoretical possibility of an increased risk of severe dengue as a consequence of vaccination has been hypothesized but not yet observed. In October 2011, the World Health Organization (WHO) convened a consultation of experts in dengue, vaccine regulation and vaccine safety to review the current scientific evidence regarding safety concerns associated with live attenuated dengue vaccines and, in particular, to consider methodological approaches for their long-term evaluation. In this paper we summarize the scientific background and methodological considerations relevant to the safety assessment of these vaccines. Careful planning and a coordinated approach to safety assessment are recommended to ensure adequate long-term evaluation of dengue vaccines that will support their introduction and continued use.

  7. Genetic engineering of Francisella tularensis LVS for use as a novel live vaccine platform against Pseudomonas aeruginosa infections.

    PubMed

    Robinson, Cory M; Kobe, Brianna N; Schmitt, Deanna M; Phair, Brian; Gilson, Tricia; Jung, Joo-Yong; Roberts, Lawton; Liao, Jialin; Camerlengo, Chelsea; Chang, Brandon; Davis, Mackenzie; Figurski, Leah; Sindeldecker, Devin; Horzempa, Joseph

    2015-01-01

    Francisella tularensis LVS (Live Vaccine Strain) is an attenuated bacterium that has been used as a live vaccine. Patients immunized with this organism show a very long-term memory response (over 30 years post vaccination) evidenced by the presence of indicators of robust cell-mediated immunity. Because F. tularensis LVS is such a potent vaccine, we hypothesized that this organism would be an effective vaccine platform. First, we sought to determine if we could genetically modify this strain to produce protective antigens of a heterologous pathogen. Currently, there is not a licensed vaccine against the important opportunistic bacterial pathogen, Pseudomonas aeruginosa. Because many P. aeruginosa strains are also drug resistant, the need for effective vaccines is magnified. Here, F. tularensis LVS was genetically modified to express surface proteins PilAPa, OprFPa, and FliCPa of P. aeruginosa. Immunization of mice with LVS expressing the recombinant FliCPa led to a significant production of antibodies specific for P. aeruginosa. However, mice that had been immunized with LVS expressing PilAPa or OprFPa did not produce high levels of antibodies specific for P. aerugionsa. Therefore, the recombinant LVS strain engineered to produce FliCPa may be able to provide immune protection against a P. aeruginosa challenge. However for future use of this vaccine platform, selection of the appropriate recombinant antigen is critical as not all recombinant antigens expressed in this strain were immunogenic.

  8. Rational design of genetically stable, live-attenuated poliovirus vaccines of all three serotypes: relevance to poliomyelitis eradication.

    PubMed

    Macadam, Andrew J; Ferguson, Geraldine; Stone, David M; Meredith, Janet; Knowlson, Sarah; Auda, Ghazi; Almond, Jeffrey W; Minor, Philip D

    2006-09-01

    The global eradication of poliomyelitis caused by wild-type virus is likely to be completed within the next few years, despite immense logistic and political difficulties, and may ultimately be followed by the cessation of vaccination. However, the existing live-attenuated vaccines have the potential to revert to virulence, causing occasional disease, and viruses can be shed by immunocompromised individuals for prolonged periods of time. Moreover, several outbreaks of poliomyelitis have been shown to be caused by viruses derived from the Sabin vaccine strains. The appearance of such strains depends on the prevailing circumstances but poses a severe obstacle to strategies for stopping vaccination. Vaccine strains that are incapable of reversion at a measurable rate would provide a possible solution. Here, we describe the constructions of strains of type 3 poliovirus that are stabilized by the introduction of four mutations in the 5' noncoding region compared to the present vaccine. The strains are genetically and phenotypically stable under conditions where the present vaccine loses the attenuating mutation in the 5' noncoding region completely. Type 1 and type 2 strains in which the entire 5' noncoding regions of Sabin 1 and Sabin 2 were replaced exactly with that of one of the type 3 strains were also constructed. The genetic stability of 5' noncoding regions of these viruses matched that of the type 3 strains, but significant phenotypic reversion occurred, illustrating the potential limitations of a rational approach to the genetic stabilization of live RNA virus vaccines.

  9. Genetic engineering of Francisella tularensis LVS for use as a novel live vaccine platform against Pseudomonas aeruginosa infections

    PubMed Central

    Robinson, Cory M; Kobe, Brianna N; Schmitt, Deanna M; Phair, Brian; Gilson, Tricia; Jung, Joo-Yong; Roberts, Lawton; Liao, Jialin; Camerlengo, Chelsea; Chang, Brandon; Davis, Mackenzie; Figurski, Leah; Sindeldecker, Devin; Horzempa, Joseph

    2015-01-01

    Francisella tularensis LVS (Live Vaccine Strain) is an attenuated bacterium that has been used as a live vaccine. Patients immunized with this organism show a very long-term memory response (over 30 years post vaccination) evidenced by the presence of indicators of robust cell-mediated immunity. Because F. tularensis LVS is such a potent vaccine, we hypothesized that this organism would be an effective vaccine platform. First, we sought to determine if we could genetically modify this strain to produce protective antigens of a heterologous pathogen. Currently, there is not a licensed vaccine against the important opportunistic bacterial pathogen, Pseudomonas aeruginosa. Because many P. aeruginosa strains are also drug resistant, the need for effective vaccines is magnified. Here, F. tularensis LVS was genetically modified to express surface proteins PilAPa, OprFPa, and FliCPa of P. aeruginosa. Immunization of mice with LVS expressing the recombinant FliCPa led to a significant production of antibodies specific for P. aeruginosa. However, mice that had been immunized with LVS expressing PilAPa or OprFPa did not produce high levels of antibodies specific for P. aerugionsa. Therefore, the recombinant LVS strain engineered to produce FliCPa may be able to provide immune protection against a P. aeruginosa challenge. However for future use of this vaccine platform, selection of the appropriate recombinant antigen is critical as not all recombinant antigens expressed in this strain were immunogenic. PMID:25617059

  10. In Vivo Characterization of the Murine Intranasal Model for Assessing the Immunogenicity of Attenuated Salmonella enterica Serovar Typhi Strains as Live Mucosal Vaccines and as Live Vectors

    PubMed Central

    Pickett, Thames E.; Pasetti, Marcela F.; Galen, James E.; Sztein, Marcelo B.; Levine, Myron M.

    2000-01-01

    Attenuated Salmonella enterica serovar Typhi live vector vaccine strains are highly immunogenic in mice following intranasal but not orogastric inoculation. To elucidate the relationship between organs within which vaccine organisms are found and the induction of specific serum immunoglobulin G (IgG) antibodies, we examined the in vivo distribution of serovar Typhi vaccine strain CVD 908-htrA following intranasal administration. Vaccine organisms were cultured from the nasal lymphoid tissue (NALT), lungs, and Peyer's patches 2 min after intranasal inoculation. Vaccine organisms persisted longer in NALT than in other organs. By decreasing the volume of intranasal inoculum containing 109 CFU (from a single 30- or 10-μl dose to four 2.5-μl doses given over the course of 1 h), we were able to significantly reduce the number of vaccine organisms isolated from the lungs (P < 0.05) without reducing the number of vaccine organisms in NALT. Reducing the number of vaccine organisms in the lungs resulted in a significant decrease in the serum tetanus antitoxin response elicited by CVD 908-htrA expressing tetanus toxin fragment C under the control of the redox-responsive nir15 promoter. In contrast, a similar construct expressing tetanus toxin fragment C under control of the constitutive lpp promoter stimulated a strong serum IgG tetanus antitoxin response with both inoculation regimens. The data suggest that following intranasal inoculation, NALT is a sufficient inductive site for elicitation of an immune response against both the live vector and heterologous antigen and, as occurs following oral inoculation of humans, attenuated serovar Typhi vaccine organisms elicit serum IgG responses. PMID:10603389

  11. The live attenuated bovine viral diarrhea virus components of a multi-valent vaccine confer protection against fetal infection.

    PubMed

    Kovács, Ferenc; Magyar, Tibor; Rinehart, Carol; Elbers, Knut; Schlesinger, Kathy; Ohnesorge, William Charles

    2003-10-17

    Fetal infection with bovine virus diarrhea virus (BVDV) causes severe economic loss and virus spread in cattle. This study investigated the ability of modified live BVDV I and II components of a commercially available modified live virus (MLV) vaccine (Breed-Back FP 10, Boehringer Ingelheim Vetmedica Inc.) to prevent fetal infection and abortion, and therefore the birth of persistently infected animals. Heifers immunized with vaccine 4-8 weeks before insemination showed no adverse effects. All vaccinated animals had seroconverted to BVDV 4 weeks after immunization. Pregnant heifers were divided into two vaccination and two control groups and challenged with type I or II BVDV on days 60-90 of gestation. Seroconversion, clinical signs, immunosuppression, viremia, mortality, abortion rate, and fetal infection were studied. Post-challenge, 6/11 (type I challenged) and 8/11 (type II challenged) vaccinated heifers were free from clinical signs of BVD. Post-challenge clinical signs noted in the vaccinated groups were mild to moderate, while all unvaccinated controls had clinical signs ranging from moderate to severe. Viremia was not detected post-challenge in any of the vaccinated heifers. However, 100% of the controls were BVDV viremic on at least 1 day post-challenge. One of 22 vaccinated heifers had transient leukopenia, whereas 2/8 and 6/7 unvaccinated heifers in control groups I and II, respectively, had transient leukopenia. Type II BVDV infection led to abortion or death in 86% of unvaccinated heifers. The corresponding vaccinated group showed no deaths or abortions. All control group fetuses were infected with BVDV. The test vaccine gave 91% (type I BVDV challenged) and 100% (type II BVDV challenged) protection from fetal infection. This vaccine is safe and effective against fetal infection, abortion (type II BVDV) and the birth of persistently infected animals.

  12. The Long-Term Safety, Public Health Impact, and Cost-Effectiveness of Routine Vaccination with a Recombinant, Live-Attenuated Dengue Vaccine (Dengvaxia): A Model Comparison Study

    PubMed Central

    Longini, Ira; Lourenco, Jose; Pearson, Carl A. B.; Reiner, Robert C.; Mier-y-Terán-Romero, Luis; Vannice, Kirsten

    2016-01-01

    Background Large Phase III trials across Asia and Latin America have recently demonstrated the efficacy of a recombinant, live-attenuated dengue vaccine (Dengvaxia) over the first 25 mo following vaccination. Subsequent data collected in the longer-term follow-up phase, however, have raised concerns about a potential increase in hospitalization risk of subsequent dengue infections, in particular among young, dengue-naïve vaccinees. We here report predictions from eight independent modelling groups on the long-term safety, public health impact, and cost-effectiveness of routine vaccination with Dengvaxia in a range of transmission settings, as characterised by seroprevalence levels among 9-y-olds (SP9). These predictions were conducted for the World Health Organization to inform their recommendations on optimal use of this vaccine. Methods and Findings The models adopted, with small variations, a parsimonious vaccine mode of action that was able to reproduce quantitative features of the observed trial data. The adopted mode of action assumed that vaccination, similarly to natural infection, induces transient, heterologous protection and, further, establishes a long-lasting immunogenic memory, which determines disease severity of subsequent infections. The default vaccination policy considered was routine vaccination of 9-y-old children in a three-dose schedule at 80% coverage. The outcomes examined were the impact of vaccination on infections, symptomatic dengue, hospitalised dengue, deaths, and cost-effectiveness over a 30-y postvaccination period. Case definitions were chosen in accordance with the Phase III trials. All models predicted that in settings with moderate to high dengue endemicity (SP9 ≥ 50%), the default vaccination policy would reduce the burden of dengue disease for the population by 6%–25% (all simulations: –3%–34%) and in high-transmission settings (SP9 ≥ 70%) by 13%–25% (all simulations: 10%– 34%). These endemicity levels are

  13. Evaluation of eight live attenuated vaccine candidates for protection against challenge with virulent Mycobacterium avium subspecies paratuberculosis in mice.

    PubMed

    Bannantine, John P; Everman, Jamie L; Rose, Sasha J; Babrak, Lmar; Katani, Robab; Barletta, Raúl G; Talaat, Adel M; Gröhn, Yrjö T; Chang, Yung-Fu; Kapur, Vivek; Bermudez, Luiz E

    2014-01-01

    Johne's disease is caused by Mycobacterium avium subsp. paratuberculosis (MAP), which results in serious economic losses worldwide in farmed livestock such as cattle, sheep, and goats. To control this disease, an effective vaccine with minimal adverse effects is needed. In order to identify a live vaccine for Johne's disease, we evaluated eight attenuated mutant strains of MAP using a C57BL/6 mouse model. The persistence of the vaccine candidates was measured at 6, 12, and 18 weeks post vaccination. Only strains 320, 321, and 329 colonized both the liver and spleens up until the 12-week time point. The remaining five mutants showed no survival in those tissues, indicating their complete attenuation in the mouse model. The candidate vaccine strains demonstrated different levels of protection based on colonization of the challenge strain in liver and spleen tissues at 12 and 18 weeks post vaccination. Based on total MAP burden in both tissues at both time points, strain 315 (MAP1566::Tn5370) was the most protective whereas strain 318 (intergenic Tn5367 insertion between MAP0282c and MAP0283c) had the most colonization. Mice vaccinated with an undiluted commercial vaccine preparation displayed the highest bacterial burden as well as enlarged spleens indicative of a strong infection. Selected vaccine strains that showed promise in the mouse model were moved forward into a goat challenge model. The results suggest that the mouse trial, as conducted, may have a relatively poor predictive value for protection in a ruminant host such as goats.

  14. Characterization of Francisella tularensis Schu S4 defined mutants as live-attenuated vaccine candidates.

    PubMed

    Santiago, Araceli E; Mann, Barbara J; Qin, Aiping; Cunningham, Aimee L; Cole, Leah E; Grassel, Christen; Vogel, Stefanie N; Levine, Myron M; Barry, Eileen M

    2015-08-01

    Francisella tularensis (Ft), the etiological agent of tularemia and a Tier 1 select agent, has been previously weaponized and remains a high priority for vaccine development. Ft tularensis (type A) and Ft holarctica (type B) cause most human disease. We selected six attenuating genes from the live vaccine strain (LVS; type B), F. novicida and other intracellular bacteria: FTT0507, FTT0584, FTT0742, FTT1019c (guaA), FTT1043 (mip) and FTT1317c (guaB) and created unmarked deletion mutants of each in the highly human virulent Ft strain Schu S4 (Type A) background. FTT0507, FTT0584, FTT0742 and FTT1043 Schu S4 mutants were not attenuated for virulence in vitro or in vivo. In contrast, Schu S4 gua mutants were unable to replicate in murine macrophages and were attenuated in vivo, with an i.n. LD50 > 10(5) CFU in C57BL/6 mice. However, the gua mutants failed to protect mice against lethal challenge with WT Schu S4, despite demonstrating partial protection in rabbits in a previous study. These results contrast with the highly protective capacity of LVS gua mutants against a lethal LVS challenge in mice, and underscore differences between these strains and the animal models in which they are evaluated, and therefore have important implications for vaccine development.

  15. CD8 knockout mice are protected from challenge by vaccination with WR201, a live attenuated mutant of Brucella melitensis.

    PubMed

    Yingst, Samuel L; Izadjoo, Mina; Hoover, David L

    2013-01-01

    CD8+ T cells have been reported to play an important role in defense against B. abortus infection in mouse models. In the present report, we use CD8 knockout mice to further elucidate the role of these cells in protection from B. melitensis infection. Mice were immunized orally by administration of B. melitensis WR201, a purine auxotrophic attenuated vaccine strain, then challenged intranasally with B. melitensis 16M. In some experiments, persistence of WR201 in the spleens of CD8 knockout mice was slightly longer than that in the spleens of normal mice. However, development of anti-LPS serum antibody, antigen-induced production of γ-interferon (IFN-γ) by immune splenic lymphocytes, protection against intranasal challenge, and recovery of nonimmunized animals from intranasal challenge were similar between normal and knockout animals. Further, primary Brucella infection was not exacerbated in perforin knockout and Fas-deficient mice and these animals' anti-Brucella immune responses were indistinguishable from those of normal mice. These results indicate that CD8+ T cells do not play an essential role as either cytotoxic cells or IFN-γ producers, yet they do participate in a specific immune response to immunization and challenge in this murine model of B. melitensis infection.

  16. Development and clinical evaluation of multiple investigational monovalent DENV vaccines to identify components for inclusion in a live attenuated tetravalent DENV vaccine.

    PubMed

    Durbin, Anna P; Kirkpatrick, Beth D; Pierce, Kristen K; Schmidt, Alexander C; Whitehead, Stephen S

    2011-09-23

    The Laboratory of Infectious Diseases at the National Institute of Allergy and Infectious Diseases, National Institutes of Health has been engaged in an effort to develop a safe, efficacious, and affordable live attenuated tetravalent dengue vaccine (LATV) for more than ten years. Numerous recombinant monovalent DENV vaccine candidates have been evaluated in the SCID-HuH-7 mouse and in rhesus macaques to identify those candidates with a suitable attenuation phenotype. In addition, the ability of these candidates to infect and disseminate in Aedes mosquitoes had also been determined. Those candidates that were suitably attenuated in SCID-HuH-7 mice, rhesus macaques, and mosquitoes were selected for further evaluation in humans. This review will describe the generation of multiple candidate vaccines directed against each DENV serotype, the preclinical and clinical evaluation of these candidates, and the process of selecting suitable candidates for inclusion in a LATV dengue vaccine.

  17. Effect of vaccination with a modified live porcine reproductive and respiratory syndrome virus vaccine on growth performance in fattening pigs under field conditions

    PubMed Central

    LYOO, Kwang-Soo; CHOI, Jong-Young; HAHN, Tae-Wook; PARK, Kun Taek; KIM, Hye Kwon

    2016-01-01

    Porcine reproductive and respiratory syndrome virus (PRRSV) has caused significant economic losses to the global swine industry. The present study aimed to evaluate the efficacy of a commercial PRRSV modified live virus (MLV) vaccine in conventionally reared growing/finishing pigs. Four barns were designated for groups A, B, C and D in the growing-to-finishing site. All pigs of the A barn were vaccinated with a commercial PRRSV MLV vaccine, whereas pigs of the B, C or D barn as control groups were unvaccinated. Twenty pigs randomly selected and tagged from each barn were serially bled at 0, 20, 40 and 60 day-post-vaccination, and tested for serological response with a commercial enzyme-linked immunosorbent assay kit. Body weights were measured to calculate the average-daily-weight gain (ADG). Serological assays indicated that the seropositivity of the PRRSV-vaccinated group was higher than that of the unvaccinated groups at 40 day-post-vaccination. ADG of group A was significantly higher than that of groups B and C, and the mean weights of groups A, B, C and D were 0.82 ± 0.017, 0.76 ± 0.016, 0.74 ± 0.019 and 0.81 ± 0.018 kg, respectively. In conclusion, the present study reports the serological responses and growth performance parameters by the PRRSV MLV vaccine in growing/finishing pigs under field conditions. PMID:27264966

  18. Protection induced by commercially available live-attenuated and recombinant viral vector vaccines against infectious laryngotracheitis virus in broiler chickens.

    PubMed

    Vagnozzi, Ariel; Zavala, Guillermo; Riblet, Sylva M; Mundt, Alice; García, Maricarmen

    2012-01-01

    Viral vector vaccines using fowl poxvirus (FPV) and herpesvirus of turkey (HVT) as vectors and carrying infectious laryngotracheitis virus (ILTV) genes are commercially available to the poultry industry in the USA. Different sectors of the broiler industry have used these vaccines in ovo or subcutaneously, achieving variable results. The objective of the present study was to determine the efficacy of protection induced by viral vector vaccines as compared with live-attenuated ILTV vaccines. The HVT-LT vaccine was more effective than the FPV-LT vaccine in mitigating the disease and reducing levels of challenge virus when applied in ovo or subcutaneously, particularly when the challenge was performed at 57 days rather than 35 days of age. While the FPV-LT vaccine mitigated clinical signs more effectively when administered subcutaneously than in ovo, it did not reduce the concentration of challenge virus in the trachea by either application route. Detection of antibodies against ILTV glycoproteins expressed by the viral vectors was a useful criterion to assess the immunogenicity of the vectors. The presence of glycoprotein I antibodies detected pre-challenge and post challenge in chickens vaccinated with HVT-LT indicated that the vaccine induced a robust antibody response, which was paralleled by significant reduction of clinical signs. The chicken embryo origin vaccine provided optimal protection by significantly mitigating the disease and reducing the challenge virus in chickens vaccinated via eye drop. The viral vector vaccines, applied in ovo and subcutaneously, provided partial protection, reducing to some degree clinical signs, and challenge VIRUS replication in the trachea.

  19. Efficacy of an anticoccidial live vaccine in prevention of necrotic enteritis in chickens.

    PubMed

    Bangoura, Berit; Alnassan, Alaa Aldin; Lendner, Matthias; Shehata, Awad Ali; Krüger, Monika; Daugschies, Arwid

    2014-10-01

    Necrotic enteritis (NE) is an important disease in poultry caused by Clostridium perfringens combined with predisposing factors, mainly eimeriosis. In the present study, we investigated the protective effect of a commercial attenuated anticoccidial live vaccine against NE in a clinical infection model using 60 day-old chicks. Vaccination was performed on study day (SD) 1 with natural booster-infections for 4 weeks from Eimeria spp. oocysts present in litter. On SD 28, five groups were formed (n=12): group V+/C-E- (vaccinated, uninfected), group V+/C-E+ (vaccinated, infected with Eimeria spp.), group V+/C+E+ (vaccinated, infected with clostridia and Eimeria spp.), group V-/C+E+ (unvaccinated, infected with clostridia and Eimeria spp.), and group NC (negative control). Efficacy was measured by clinical parameters, pathogen multiplication, and pathological parameters assessed during two necropsies on SD 34 and SD 40, respectively. Additionally, cytokine expression was measured in gut and spleen tissues at necropsy. Clinical signs of NE were observed only in the coinfected groups, mainly in group V-/C+E+. Accordingly, lowest body weight gain was observed in group V-/C+E+ (301.8 g from SD 28 to SD 40; group NC: 626.2 g). Oocyst excretion varied significantly (P<0.01) between all Eimeria spp. infected groups and was highest in group V-/C+E+, followed by V+/C+E+, and lowest in group V+/C-E+. NE typical intestinal lesions showed only in groups V+/C+E+ and V-/C+E+. The intestinal mucosa featured partly severe lesions in the jejunum, C. perfringens colonization was histologically visible. Upregulation of IFN-γ, was observed in the jejunal tissue of group V-/C+E+ (P<0.01 (SD 34) or P<0.05 (SD 40) compared to all other groups). IL-10 and IL-12 were upregulated in group V-/C+E+, IL-10 also in group V+/C+E+ (SD 40) while IL-2 expression remained unaltered. In conclusion, vaccination against coccidiosis was effective in preventing NE in a mixed infection comparable to field

  20. Live SIV vaccine correlate of protection: local antibody production and concentration on the path of virus entry

    PubMed Central

    Li, Qingsheng; Zeng, Ming; Duan, Lijie; Voss, James E.; Smith, Anthony J.; Pambuccian, Stefan; Shang, Liang; Wietgrefe, Stephen; Southern, Peter J.; Reilly, Cavan S.; Skinner, Pamela J.; Zupancic, Mary L.; Carlis, John V.; Piatak, Michael; Waterman, Diane; Reeves, R. Keith; Masek-Hammerman, Katherine; Derdeyn, Cynthia A.; Alpert, Michael D.; Evans, David T.; Kohler, Heinz; Muller, Sybille; Robinson, James; Lifson, Jeffrey D.; Burton, Dennis R.; Johnson, R. Paul; Haase, Ashley T.

    2014-01-01

    We sought design principles for a vaccine to prevent HIV transmission to women by identifying correlates of protection conferred by a highly effective live attenuated SIV vaccine in the rhesus macaque animal model. We show that SIVmac239Δnef vaccination recruits plasma cells and induces ectopic lymphoid follicle formation beneath the mucosal epithelium in the rhesus macaque female reproductive tract. The plasma cells and ectopic follicles produce IgG antibodies reactive with viral envelope glycoprotein gp41 trimers, and these antibodies are concentrated on the path of virus entry by the neonatal Fc receptor (FcRn) in cervical reserve epithelium and in vaginal epithelium. This local antibody production and delivery system correlated spatially and temporally with the maturation of local protection against high dose pathogenic SIV vaginal challenge. Thus, designing vaccines to elicit production and concentration of antibodies at mucosal frontlines could aid development of an effective vaccine to protect women against HIV-1. PMID:25135832

  1. Live simian immunodeficiency virus vaccine correlate of protection: local antibody production and concentration on the path of virus entry.

    PubMed

    Li, Qingsheng; Zeng, Ming; Duan, Lijie; Voss, James E; Smith, Anthony J; Pambuccian, Stefan; Shang, Liang; Wietgrefe, Stephen; Southern, Peter J; Reilly, Cavan S; Skinner, Pamela J; Zupancic, Mary L; Carlis, John V; Piatak, Michael; Waterman, Diane; Reeves, R Keith; Masek-Hammerman, Katherine; Derdeyn, Cynthia A; Alpert, Michael D; Evans, David T; Kohler, Heinz; Müller, Sybille; Robinson, James; Lifson, Jeffrey D; Burton, Dennis R; Johnson, R Paul; Haase, Ashley T

    2014-09-15

    We sought design principles for a vaccine to prevent HIV transmission to women by identifying correlates of protection conferred by a highly effective live attenuated SIV vaccine in the rhesus macaque animal model. We show that SIVmac239Δnef vaccination recruits plasma cells and induces ectopic lymphoid follicle formation beneath the mucosal epithelium in the rhesus macaque female reproductive tract. The plasma cells and ectopic follicles produce IgG Abs reactive with viral envelope glycoprotein gp41 trimers, and these Abs are concentrated on the path of virus entry by the neonatal FcR in cervical reserve epithelium and in vaginal epithelium. This local Ab production and delivery system correlated spatially and temporally with the maturation of local protection against high-dose pathogenic SIV vaginal challenge. Thus, designing vaccines to elicit production and concentration of Abs at mucosal frontlines could aid in the development of an effective vaccine to protect women against HIV-1.

  2. Evaluating the effectiveness, impact and safety of live attenuated and seasonal inactivated influenza vaccination: protocol for the Seasonal Influenza Vaccination Effectiveness II (SIVE II) study

    PubMed Central

    Lone, Nazir I; Kavanagh, Kimberley; Robertson, Chris; McMenamin, Jim; von Wissmann, Beatrix; Vasileiou, Eleftheria; Butler, Chris; Ritchie, Lewis D; Gunson, Rory; Schwarze, Jürgen; Sheikh, Aziz

    2017-01-01

    Introduction Seasonal (inactivated) influenza vaccination is recommended for all individuals aged 65+ and in individuals under 65 who are at an increased risk of complications of influenza infection, for example, people with asthma. Live attenuated influenza vaccine (LAIV) was recommended for children as they are thought to be responsible for much of the transmission of influenza to the populations at risk of serious complications from influenza. A phased roll-out of the LAIV pilot programme began in 2013/2014. There is limited evidence for vaccine effectiveness (VE) in the populations targeted for influenza vaccination. The aim of this study is to examine the safety and effectiveness of the live attenuated seasonal influenza vaccine programme in children and the inactivated seasonal influenza vaccination programme among different age and at-risk groups of people. Methods and analysis Test negative and cohort study designs will be used to estimate VE. A primary care database covering 1.25 million people in Scotland for the period 2000/2001 to 2015/2016 will be linked to the Scottish Immunisation Recall Service (SIRS), Health Protection Scotland virology database, admissions to Scottish hospitals and the Scottish death register. Vaccination status (including LAIV uptake) will be determined from the primary care and SIRS database. The primary outcome will be influenza-positive real-time PCR tests carried out in sentinel general practices and other healthcare settings. Secondary outcomes include influenza-like illness and asthma-related general practice consultations, hospitalisations and death. An instrumental variable analysis will be carried out to account for confounding. Self-controlled study designs will be used to estimate the risk of adverse events associated with influenza vaccination. Ethics and dissemination We obtained approval from the National Research Ethics Service Committee, West Midlands—Edgbaston. The study findings will be presented at

  3. Safety and efficacy of a metabolic drift live attenuated Salmonella Gallinarum vaccine against fowl typhoid.

    PubMed

    Shehata, Awad Ali; Sultan, Hesham; Hafez, Hafez M; Krüger, Monika

    2013-03-01

    Fowl typhoid (FT), a systemic disease that results in septicemia in poultry, is caused by Salmonella enterica serovar Gallinarum biovar Gallinarum (SG). Mortality and morbidity rates from FT can reach up to 80%. Attenuated live Salmonella vaccine candidates have received considerable attention because they confer solid immunity, and they can produce systemic and mucosal immunity in the gut when administered orally. In the present study, five metabolic drift (MD) mutants with a single-(designated SG-Rif1, SG-Sm6) or double-attenuating marker (designated SG-Rif1-Sm4, SG-Sm6-Rif10, and SG-Rif1-Sm10) were isolated. The relative colony sizes to wild-type strain after 24 hr at 37 C incubation were 50%, 40%, 30%, 30%, and 20%, respectively. The probability of a back mutation can almost be excluded because the reduced colony sizes were stable after at least 50 passages on culture media. The safety and immunogenicity were evaluated in susceptible 1-day-old commercial layer chickens. After oral administration of 10(8) colony-forming units (CFU), all developed MD mutants proved to be safe and did not cause death of any infected birds during 15 days postvaccination, whereas chickens receiving 10(6) CFU SG wild-type strain showed a high mortality rate (40%). Vaccination of commercial layer chicks with SG-Rif1, SG-Sm6, SG-Rif1-Sm4, and SG-Sm6-Rif10 MD mutants could protect chickens against challenge by homologous wild-type strain; however, SG-Rif1-Sm10 could not protect against challenge, indicating hyperattenuation. In conclusion, vaccination with SG MD mutant vaccine appears to be safe and offers protection against FT in chickens.

  4. Immunogenic response induced by wzm and wzt gene deletion mutants from Brucella abortus S19.

    PubMed

    Wang, Xiu-Ran; Yan, Guang-Mou; Zhang, Rui; Lang, Xu-Long; Yang, Yan-Ling; Li, Xiao-Yan; Chen, Si; Qian, Jing; Wang, Xing-Long

    2014-02-01

    Brucellosis is an infectious disease affecting humans and animals worldwide. Effective methods of control include inducing immunity in animals by vaccination and elimination. Brucella abortus S19 is one of the popular vaccines for control of cattle brucellosis, as it has low virulence. In this paper, allelic exchange plasmids of wzm and wzt genes were constructed and partially knocked out to evaluate the effects on the induction of immunity to Brucella abortus S19 mutants. Cytokine secretion in vitro, INF-γ induction in vivo and antibody dynamics were evaluated. These data suggested that the immunity-eliciting ability of the wzm and wzt gene deletion mutants was similar, although reduced compared with the S19 strain. The results demonstrated that the wzt gene may be more important in the regulation of the induction of immunity than the wzm gene.

  5. Safety and immunogenicity of a rederived, live-attenuated dengue virus vaccine in healthy adults living in Thailand: a randomized trial.

    PubMed

    Watanaveeradej, Veerachai; Gibbons, Robert V; Simasathien, Sriluck; Nisalak, Ananda; Jarman, Richard G; Kerdpanich, Angkool; Tournay, Elodie; De La Barrerra, Rafael; Dessy, Francis; Toussaint, Jean-François; Eckels, Kenneth H; Thomas, Stephen J; Innis, Bruce L

    2014-07-01

    Safety and immunogenicity of two formulations of a live-attenuated tetravalent dengue virus (TDEN) vaccine produced using rederived master seeds from a precursor vaccine were tested against a placebo control in a phase II, randomized, double blind trial (NCT00370682). Two doses were administered 6 months apart to 120 healthy, predominantly flavivirus-primed adults (87.5% and 97.5% in the two vaccine groups and 92.5% in the placebo group). Symptoms and signs reported after vaccination were mild to moderate and transient. There were no vaccine-related serious adverse events or dengue cases reported. Asymptomatic, low-level viremia (dengue virus type 2 [DENV-2], DENV-3, or DENV-4) was detected in 5 of 80 vaccine recipients. One placebo recipient developed a subclinical natural DENV-1 infection. All flavivirus-unprimed subjects and at least 97.1% of flavivirus-primed subjects were seropositive to antibodies against all four DENV types 1 and 3 months post-TDEN dose 2. The TDEN vaccine was immunogenic with an acceptable safety profile in flavivirus-primed adults.

  6. Vaccinations

    MedlinePlus

    ... vaccinated? For many years, a set of annual vaccinations was considered normal and necessary for dogs and ... to protect for a full year. Consequently, one vaccination schedule will not work well for all pets. ...

  7. O-2'-hydroxypropyltrimethyl ammonium chloride chitosan nanoparticles for the delivery of live Newcastle disease vaccine.

    PubMed

    Dai, Chunxiao; Kang, Hong; Yang, Wanqiu; Sun, Jinyan; Liu, Chunlong; Cheng, Guogang; Rong, Guangyu; Wang, Xiaohua; Wang, Xin; Jin, Zheng; Zhao, Kai

    2015-10-05

    A novel complex chitosan derivative, O-2'-hydroxypropyltrimethyl ammonium chloride chitosan (O-2'-HACC), was synthesized and used to make nanoparticles as a delivery vehicle for live attenuated Newcastle disease vaccine. We found that O-2'-HACC had high antimicrobial activity, low toxicity, and a high safety level. Newcastle disease virus (NDV) was then encapsulated in the O-2'-HACC nanoparticles (NDV/La Sota-O-2'-HACC-NPs) by the ionic crosslinking method, and the properties of the resulting nanoparticles were determined by transmission electron microscopy, Zeta potential analysis, Fourier transform infrared spectroscopy, proton nuclear magnetic resonance spectroscopy, and X-ray diffraction. NDV/La Sota-O-2'-HACC-NPs had regular spherical morphologies and high stability, with an encapsulation efficiency of 95.68 ± 2.2% and a loading capacity of 58.75 ± 4.03%. An in vitro release assay indicated that release of NDV from NDV/La Sota-O-2'-HACC-NPs occurred slowly. Specific pathogen-free chickens immunized with NDV/La Sota-O-2'-HACC-NPs intranasally had much stronger cellular, humoral and mucosal immune responses than did those immunized intramuscularly or with live attenuated Newcastle disease vaccine. NDV/La Sota-O-2'-HACC-NPs are a novel drug delivery carrier with immense potential in medical applications.

  8. A live RSV vaccine with engineered thermostability is immunogenic in cotton rats despite high attenuation.

    PubMed

    Stobart, Christopher C; Rostad, Christina A; Ke, Zunlong; Dillard, Rebecca S; Hampton, Cheri M; Strauss, Joshua D; Yi, Hong; Hotard, Anne L; Meng, Jia; Pickles, Raymond J; Sakamoto, Kaori; Lee, Sujin; Currier, Michael G; Moin, Syed M; Graham, Barney S; Boukhvalova, Marina S; Gilbert, Brian E; Blanco, Jorge C G; Piedra, Pedro A; Wright, Elizabeth R; Moore, Martin L

    2016-12-21

    Respiratory syncytial virus (RSV) is a leading cause of infant hospitalization and there remains no pediatric vaccine. RSV live-attenuated vaccines (LAVs) have a history of safe testing in infants; however, achieving an effective balance of attenuation and immunogenicity has proven challenging. Here we seek to engineer an RSV LAV with enhanced immunogenicity. Genetic mapping identifies strain line 19 fusion (F) protein residues that correlate with pre-fusion antigen maintenance by ELISA and thermal stability of infectivity in live RSV. We generate a LAV candidate named OE4 which expresses line 19F and is attenuated by codon-deoptimization of non-structural (NS1 and NS2) genes, deletion of the small hydrophobic (SH) gene, codon-deoptimization of the attachment (G) gene and ablation of the secreted form of G. OE4 (RSV-A2-dNS1-dNS2-ΔSH-dGm-Gsnull-line19F) exhibits elevated pre-fusion antigen levels, thermal stability, immunogenicity, and efficacy despite heavy attenuation in the upper and lower airways of cotton rats.

  9. A live RSV vaccine with engineered thermostability is immunogenic in cotton rats despite high attenuation

    PubMed Central

    Stobart, Christopher C.; Rostad, Christina A.; Ke, Zunlong; Dillard, Rebecca S.; Hampton, Cheri M.; Strauss, Joshua D.; Yi, Hong; Hotard, Anne L.; Meng, Jia; Pickles, Raymond J.; Sakamoto, Kaori; Lee, Sujin; Currier, Michael G.; Moin, Syed M.; Graham, Barney S.; Boukhvalova, Marina S.; Gilbert, Brian E.; Blanco, Jorge C. G.; Piedra, Pedro A.; Wright, Elizabeth R.; Moore, Martin L.

    2016-01-01

    Respiratory syncytial virus (RSV) is a leading cause of infant hospitalization and there remains no pediatric vaccine. RSV live-attenuated vaccines (LAVs) have a history of safe testing in infants; however, achieving an effective balance of attenuation and immunogenicity has proven challenging. Here we seek to engineer an RSV LAV with enhanced immunogenicity. Genetic mapping identifies strain line 19 fusion (F) protein residues that correlate with pre-fusion antigen maintenance by ELISA and thermal stability of infectivity in live RSV. We generate a LAV candidate named OE4 which expresses line 19F and is attenuated by codon-deoptimization of non-structural (NS1 and NS2) genes, deletion of the small hydrophobic (SH) gene, codon-deoptimization of the attachment (G) gene and ablation of the secreted form of G. OE4 (RSV-A2-dNS1-dNS2-ΔSH-dGm-Gsnull-line19F) exhibits elevated pre-fusion antigen levels, thermal stability, immunogenicity, and efficacy despite heavy attenuation in the upper and lower airways of cotton rats. PMID:28000669

  10. A live-attenuated Zika virus vaccine candidate induces sterilizing immunity in mouse models.

    PubMed

    Shan, Chao; Muruato, Antonio E; Nunes, Bruno T D; Luo, Huanle; Xie, Xuping; Medeiros, Daniele B A; Wakamiya, Maki; Tesh, Robert B; Barrett, Alan D; Wang, Tian; Weaver, Scott C; Vasconcelos, Pedro F C; Rossi, Shannan L; Shi, Pei-Yong

    2017-04-10

    Zika virus (ZIKV) infection of pregnant women can cause a wide range of congenital abnormalities, including microcephaly, in the infant, a condition now collectively known as congenital ZIKV syndrome. A vaccine to prevent or significantly attenuate viremia in pregnant women who are residents of or travelers to epidemic or endemic regions is needed to avert congenital ZIKV syndrome, and might also help to suppress epidemic transmission. Here we report on a live-attenuated vaccine candidate that contains a 10-nucleotide deletion in the 3' untranslated region of the ZIKV genome (10-del ZIKV). The 10-del ZIKV is highly attenuated, immunogenic, and protective in type 1 interferon receptor-deficient A129 mice. Crucially, a single dose of 10-del ZIKV induced sterilizing immunity with a saturated neutralizing antibody titer, which no longer increased after challenge with an epidemic ZIKV, and completely prevented viremia. The immunized mice also developed a robust T cell response. Intracranial inoculation of 1-d-old immunocompetent CD-1 mice with 1 × 10(4) infectious focus units (IFU) of 10-del ZIKV caused no mortality, whereas infections with 10 IFU of wild-type ZIKV were lethal. Mechanistically, the attenuated virulence of 10-del ZIKV may be due to decreased viral RNA synthesis and increased sensitivity to type-1-interferon inhibition. The attenuated 10-del ZIKV was incapable of infecting mosquitoes after oral feeding of spiked-blood meals, representing an additional safety feature. Collectively, the safety and efficacy results suggest that further development of this promising, live-attenuated ZIKV vaccine candidate is warranted.

  11. Brucella abortus mutants lacking ATP-binding cassette transporter proteins are highly attenuated in virulence and confer protective immunity against virulent B. abortus challenge in BALB/c mice.

    PubMed

    Truong, Quang Lam; Cho, Youngjae; Park, Soyeon; Park, Bo-Kyoung; Hahn, Tae-Wook

    2016-06-01

    Brucella abortus RB51 is an attenuated vaccine strain that has been most frequently used for bovine brucellosis. Although it is known to provide good protection in cattle, it still has some drawbacks including resistance to rifampicin, residual virulence and pathogenicity in humans. Thus, there has been a continuous interest on new safe and effective bovine vaccine candidates. In the present study, we have constructed unmarked mutants by deleting singly cydD and cydC genes, which encode ATP-binding cassette transporter proteins, from the chromosome of the virulent Brucella abortus isolate from Korean cow (referred to as IVK15). Both IVK15ΔcydD and ΔcydC mutants showed increased sensitivity to metal ions, hydrogen peroxide and acidic pH, which are mimic to intracellular environment during host infection. Additionally, the mutants exhibited a significant growth defect in RAW264.7 cells and greatly attenuated in mice. Vaccination of mice with either IVK15ΔcydC or IVK15ΔcydD mutant could elicit an anti-Brucella specific immunoglobulin G (IgG) and IgG subclass responses as well as enhance the secretion of interferon-gamma, and provided better protection against challenge with B. abortus strain 2308 than with the commercial B. abortus strain RB51 vaccine. Collectively, these results suggest that both IVK15ΔcydC and IVK15ΔcydD mutants could be an attenuated vaccine candidate against B. abortus.

  12. Diagnostic and vaccine chapter.

    PubMed

    Wolfram, J H; Kokanov, S K; Verkhovsky, O A

    2010-10-01

    The first report in this chapter describes the development of a killed composite vaccine. This killed vaccine is non-infectious to humans, other animals, and the environment. The vaccine has low reactivity, is non-abortive, and does not induce pathomorphological alterations to the organs of vaccinated animals. The second report of this chapter describes the diagnostic value of a competitive enzyme-linked immunosorbent assay for detecting Brucella-specific antibodies and its ability to discriminate vaccinated cattle from infected cattle. The results indicated that the competitive enzyme-linked immunosorbent assay is more sensitive than traditional tests for detecting antibodies to Brucella abortus in naturally and experimentally infected cattle.

  13. Quantitative Determination of Lethal Toxin Proteins in Culture Supernatant of Human Live Anthrax Vaccine Bacillus anthracis A16R.

    PubMed

    Zai, Xiaodong; Zhang, Jun; Liu, Ju; Liu, Jie; Li, Liangliang; Yin, Ying; Fu, Ling; Xu, Junjie; Chen, Wei

    2016-02-25

    Bacillus anthracis (B. anthracis) is the etiological agent of anthrax affecting both humans and animals. Anthrax toxin (AT) plays a major role in pathogenesis. It includes lethal toxin (LT) and edema toxin (ET), which are formed by the combination of protective antigen (PA) and lethal factor (LF) or edema factor (EF), respectively. The currently used human anthrax vaccine in China utilizes live-attenuated B. anthracis spores (A16R; pXO1+, pXO2-) that produce anthrax toxin but cannot produce the capsule. Anthrax toxins, especially LT, have key effects on both the immunogenicity and toxicity of human anthrax vaccines. Thus, determining quantities and biological activities of LT proteins expressed by the A16R strain is meaningful. Here, we explored LT expression patterns of the A16R strain in culture conditions using another vaccine strain Sterne as a control. We developed a sandwich ELISA and cytotoxicity-based method for quantitative detection of PA and LF. Expression and degradation of LT proteins were observed in culture supernatants over time. Additionally, LT proteins expressed by the A16R and Sterne strains were found to be monomeric and showed cytotoxic activity, which may be the main reason for side effects of live anthrax vaccines. Our work facilitates the characterization of anthrax vaccines components and establishment of a quality control standard for vaccine production which may ultimately help to ensure the efficacy and safety of the human anthrax vaccine A16R.

  14. Suppressing active replication of a live attenuated simian immunodeficiency virus vaccine does not abrogate protection from challenge

    SciTech Connect

    Gabriel, Benjamin; Fiebig, Uwe; Hohn, Oliver; Plesker, Roland; Coulibaly, Cheick; Cichutek, Klaus; Mühlebach, Michael D.; Bannert, Norbert; Kurth, Reinhard; Norley, Stephen

    2016-02-15

    Although safety concerns preclude the use of live attenuated HIV vaccines in humans, they provide a useful system for identifying the elusive correlates of protective immunity in the SIV/macaque animal model. However, a number of pieces of evidence suggest that protection may result from prior occupancy of susceptible target cells by the vaccine virus rather than the immune response. To address this, we developed a Nef-deletion variant of an RT-SHIV whose active replication could be shut off by treatment with RT-inhibitors. Groups of macaques were inoculated with the ∆Nef-RT-SHIV and immune responses allowed to develop before antiretroviral treatment and subsequent challenge with wild-type SIVmac239. Vaccinated animals either resisted infection fully or significantly controlled the subsequent viremia. However, there was no difference between animals undergoing replication of the vaccine virus and those without. This strongly suggests that competition for available target cells does not play a role in protection. - Highlights: • A Nef-deleted RT-SHIV was used as a live attenuated vaccine in macaques. • Vaccine virus replication was shut down to investigate its role in protection. • Ongoing vaccine virus replication did not appear to be necessary for protection. • An analysis of T- and B-cell responses failed to identify a correlate of protection.

  15. Evaluation of Brucella abortus strain RB51 and strain 19 in pronghorn antelope

    USGS Publications Warehouse

    Elzer, P.H.; Smith, J.; Roffe, T.; Kreeger, T.; Edwards, J.; Davis, D.

    2002-01-01

    Free-roaming elk and bison in the Greater Yellowstone Area remain the only wildlife reservoirs for Brucella abortus in the United States, and the large number of animals and a lack of holding facilities make it unreasonable to individually vaccinate each animal. Therefore, oral delivery is being proposed as a possible option to vaccinate these wild ungulates. One of the main problems associated with oral vaccination is the potential exposure of nontarget species to the vaccines. The purpose of this study was to determine the effects of two Brucella vaccines, strain 19 (S19) and the rough strain RB51 (SRB51), in pregnant pronghorn antelope. We conclude that S19 and SRB51 rarely colonize maternal and fetal tissues of pregnant pronghorn and were not associated with fetal death. Oral delivery of either vaccine at this dose appears to be nonhazardous to pregnant pronghorn.

  16. Evaluation of Brucella abortus strain RB51 and strain 19 in pronghorn antelope.

    PubMed

    Elzer, Philip H; Smith, J; Roffe, T; Kreeger, T; Edwards, J; Davis, D

    2002-10-01

    Free-roaming elk and bison in the Greater Yellowstone Area remain the only wildlife reservoirs for Brucella abortus in the United States, and the large number of animals and a lack of holding facilities make it unreasonable to individually vaccinate each animal. Therefore, oral delivery is being proposed as a possible option to vaccinate these wild ungulates. One of the main problems associated with oral vaccination is the potential exposure of nontarget species to the vaccines. The purpose of this study was to determine the effects of two Brucella vaccines, strain 19 (S19) and the rough strain RB51 (SRB51), in pregnant pronghorn antelope. We conclude that S19 and SRB51 rarely colonize maternal and fetal tissues of pregnant pronghorn and were not associated with fetal death. Oral delivery of either vaccine at this dose appears to be nonhazardous to pregnant pronghorn.

  17. Live Attenuated Human Salmonella Vaccine Candidates: tracking the pathogen in natural infection and stimulation of host immunity

    PubMed Central

    Galen, James E.; Buskirk, Amanda D.; Tennant, Sharon M.; Pasetti, Marcela F.

    2016-01-01

    Salmonellosis, caused by members of the genus Salmonella, is responsible for considerable global morbidity and mortality, in both animals and humans. In this review, we will discuss the pathogenesis of S. Typhi and S. Typhimurium, focusing on human Salmonella infections. We will trace the path of Salmonella through the body, including host entry sites, tissues and organs affected, and mechanisms involved in both pathogenesis and stimulation of host immunity. Careful consideration of the natural progression of disease provides an important context in which attenuated live oral vaccines can be rationally designed and developed. With this in mind, we will describe a series of attenuated live oral vaccines that have been successfully tested in clinical trials and demonstrated to be both safe and highly immunogenic. The attenuation strategies summarized in this review offer important insights into further development of attenuated vaccines against other Salmonella for which live oral candidates are currently unavailable. PMID:27809955

  18. Live Attenuated Human Salmonella Vaccine Candidates: Tracking the Pathogen in Natural Infection and Stimulation of Host Immunity.

    PubMed

    Galen, James E; Buskirk, Amanda D; Tennant, Sharon M; Pasetti, Marcela F

    2016-11-01

    Salmonellosis, caused by members of the genus Salmonella, is responsible for considerable global morbidity and mortality in both animals and humans. In this review, we will discuss the pathogenesis of Salmonella enterica serovar Typhi and Salmonella enterica serovar Typhimurium, focusing on human Salmonella infections. We will trace the path of Salmonella through the body, including host entry sites, tissues and organs affected, and mechanisms involved in both pathogenesis and stimulation of host immunity. Careful consideration of the natural progression of disease provides an important context in which attenuated live oral vaccines can be rationally designed and developed. With this in mind, we will describe a series of attenuated live oral vaccines that have been successfully tested in clinical trials and demonstrated to be both safe and highly immunogenic. The attenuation strategies summarized in this review offer important insights into further development of attenuated vaccines against other Salmonella for which live oral candidates are currently unavailable.

  19. Effects of live and killed vaccines against Mycoplasma gallisepticum on the performance characteristics of commercial layer chickens.

    PubMed

    Jacob, R; Branton, S L; Evans, J D; Leigh, S A; Peebles, E D

    2014-06-01

    Different vaccine strains of Mycoplasma gallisepticum have been used on multiple-age commercial layer farms in an effort to protect birds against virulent field-strain infections. Use of the F-strain of M. gallisepticum (FMG), as an overlay vaccine during lay, may be necessary because of the lower level of protection afforded by M. gallisepticum vaccines of low virulence given before lay. Two replicate trials were conducted to investigate effects of live and killed M. gallisepticum vaccines administered individually and in combination before lay, in conjunction with an FMG vaccine overlay after peak egg production (EP), on the performance characteristics of commercial layers. The following treatments were utilized at 10 wk of age (woa): 1) control (no vaccinations); 2) ts11 strain M. gallisepticum (ts11MG) vaccine; 3) M. gallisepticum-Bacterin vaccine (MG-Bacterin); and 4) ts11MG and MG-Bacterin vaccines combination. At 45 woa, half of the birds were overlaid with an FMG vaccine. Hen mortality, BW, egg weight, percentage hen-day EP, egg blood spots, and egg meat spots were determined at various time periods between 18 and 52 woa. The data from each trial were pooled. Treatment did not affect performance in interval I (23 to 45 woa). However, during interval II (46 to 52 woa), the EP of control and MG-Bacterin-vaccinated birds that later received an FMG vaccine overlay was lower than that in the other treatment groups. Furthermore, treatment application reduced bird BW during interval II. Despite the effects on BW and EP, no differences were observed for egg blood or meat spots among the various treatments. It is suggested that the vaccination of commercial layers before lay with ts11MG, but not MG-Bacterin, may reduce the negative impacts of an FMG overlay vaccination given during lay. These results establish that the vaccination of pullets with ts11MG in combination with the vaccination of hens with an FMG overlay, for continual protection against field-strain M

  20. Development and approval of live attenuated influenza vaccines based on Russian master donor viruses: Process challenges and success stories.

    PubMed

    Rudenko, Larisa; Yeolekar, Leena; Kiseleva, Irina; Isakova-Sivak, Irina

    2016-10-26

    Influenza is a viral infection that affects much of the global population each year. Vaccination remains the most effective tool for preventing the disease. Live attenuated influenza vaccine (LAIV) has been used since the 1950s to protect humans against seasonal influenza. LAIVs developed by the Institute of Experimental Medicine (IEM), Saint Petersburg, Russia, have been successfully used in Russia since 1987. In 2006, the World Health Organization (WHO) announced a Global action plan for influenza vaccines (GAP). WHO, recognizing potential advantages of LAIV over the inactivated influenza vaccine in a pandemic situation, included LAIV in the GAP. BioDiem Ltd., a vaccine development company based in Melbourne, Australia which held the rights for the Russian LAIV, licensed this technology to WHO in 2009. WHO was permitted to grant sub-licenses to vaccine manufacturers in newly industrialized and developing countries to use the Russian LAIV for the development, manufacture, use and sale of pandemic and seasonal LAIVs. To date, WHO has granted sub-licenses to vaccine manufacturers in China (Changchun BCHT Biotechnology Co., Ltd.), India (Serum Institute of India Pvt. Ltd.) and Thailand (Government Pharmaceutical Organization). In parallel, in 2009, IEM signed an agreement with WHO, under which IEM committed to supply pandemic and seasonal candidate vaccine viruses to the sub-licensees. This paper describes the progress made by collaborators from China, India, Russia and Thailand in developing preventive measures, including LAIV against pandemic influenza.

  1. Single-dose live-attenuated Nipah virus vaccines confer complete protection by eliciting antibodies directed against surface glycoproteins

    PubMed Central

    DeBuysscher, Blair L.; Scott, Dana; Marzi, Andrea; Prescott, Joseph; Feldmann, Heinz

    2016-01-01

    Background Nipah virus (NiV), a zoonotic pathogen causing severe respiratory illness and encephalitis in humans, emerged in Malaysia in 1998 with subsequent outbreaks on an almost annual basis since 2001 in parts of the Indian subcontinent. The high case fatality rate, human-to-human transmission, wide-ranging reservoir distribution and lack of licensed intervention options are making NiV a serious regional and potential global public health problem. The objective of this study was to develop a fast-acting, single-dose NiV vaccine that could be implemented in a ring vaccination approach during outbreaks. Methods In this study we have designed new live-attenuated vaccine vectors based on recombinant vesicular stomatitis viruses (rVSV) expressing NiV glycoproteins (G or F) or nucleoprotein (N) and evaluated their protective efficacy in Syrian hamsters, an established NiV animal disease model. We further characterized the humoral immune response to vaccination in hamsters using ELISA and neutralization assays and performed serum transfer studies. Results Vaccination of Syrian hamsters with a single dose of the rVSV vaccine vectors resulted in strong humoral immune responses with neutralizing activities found only in those animals vaccinated with rVSV expressing NiV G or F proteins. Vaccinated animals with neutralizing antibody responses were completely protected from lethal NiV disease, whereas animals vaccinated with rVSV expressing NiV N showed only partial protection. Protection of NiV G or F vaccinated animals was conferred by antibodies, most likely the neutralizing fraction, as demonstrated by serum transfer studies. Protection of N-vaccinated hamsters was not antibody-dependent indicating a role of adaptive cellular responses for protection. Conclusions The rVSV vectors expressing Nipah virus G or F are prime candidates for new ‘emergency vaccines’ to be utilized for NiV outbreak management. PMID:24631094

  2. Oral fluids as a live-animal sample for evaluating cross-reactivity and cross-protection following intranasal influenza A virus vaccination in pigs

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In North American swine there are numerous antigenically distinct influenza A virus (IAV) H1 subtypes currently circulating, making vaccine development difficult due to the inability to formulate a vaccine that provides broad cross-protection. Live-attenuated influenza virus (LAIV) vaccines provide ...

  3. [History of development of the live poliomyelitis vaccine from Sabin attenuated strains in 1959 and idea of poliomyelitis eradication].

    PubMed

    Lashkevich, V A

    2013-01-01

    In 1958 Poliomyelitis Institute in Moscow and Institute of Experimental Medicine in St. Petersburg received from A. Sabin the attenuated strains of poliomyelitis virus. The characteristics of the strains were thoroughly studied by A. A. Smorodintsev and coworkers. They found that the virulence of the strains fluctuated slightly in 10 consecutive passages through the intestine of the non-immune children. A part of the Sabin material was used by A. A. Smorodintsev and M. P. Chumakov in the beginning of 1959 for immunizing approximately 40000 children in Estonia, Lithuania, and Latvia. Epidemic poliomyelitis rate in these republics decreased from approximately 1000 cases yearly before vaccination to less than 20 in the third quarter of 1959. This was a convincing proof of the efficacy and safety of the vaccine from the attenuated Sabin strains. In 1959, according to A. Sabin's recommendation, a technology of live vaccine production was developed at the Poliomyelitis Institute, and several experimental lots of vaccine were prepared. In the second part of 1959, 13.5 million children in USSR were immunized. The epidemic poliomyelitis rate decreased 3-5 times in different regions without paralytic cases, which could be attributed to the vaccination. These results were the final proof of high efficiency and safety of live poliomyelitis vaccine from the attenuated Sabin strains. Based on these results, A. Sabin and M. P. Chumakov suggested in 1960 the idea of poliomyelitis eradication using mass immunization of children with live vaccine. 72 million persons up to 20 years old were vaccinated in USSR in 1960 with a 5 times drop in the paralytic rate. 50-year-long use of live vaccine results in poliomyelitis eradication in almost all countries worldwide. More than 10 million children were rescued from the death and palsy. Poliomyelitis eradication in a few countries where it still exists depends not on medical services but is defined by the attitude of their leaders to fight

  4. Duration of immunity in red wolves (Canis rufus) following vaccination with a modified live parvovirus and canine distemper vaccine.

    PubMed

    Anderson, Kadie; Case, Allison; Woodie, Kathleen; Waddell, William; Reed, Holly H

    2014-09-01

    There is growing information available regarding duration of immunity for core vaccines in both domestic and nondomestic species. Vaccination protocols in nondomestic canids have frequently followed guidelines developed for the domestic dog; however, these protocols can be inappropriate for nondomestic canids such as the African wild dog (Lycaon pictus), leaving some animals susceptible to infectious disease and others at risk for contracting vaccine-induced disease. In this study, red wolves (Canis rufus) were vaccinated against canine distemper virus (CDV) and canine parvovirus (CPV) and vaccination titers were followed annually for 3 yr. One hundred percent of wolves developed and maintained a positive titer to CDV for 3 yr and 96.9% of wolves developed and maintained a positive titer to CPV for 3 yr. Seroconversion for canine adenovirus was sporadic. The results of this study support decreasing the frequency of vaccine administration in the red wolf population to a triennial basis.

  5. Vaccines.gov

    MedlinePlus

    ... Statements Vaccine Approvals Features: News & Video Free Resources Vaccines are safe, effective, and save lives. Find answers ... by science, on vaccine safety. Are your child’s vaccines up to date? Getting all recommended vaccines on ...

  6. Effect of withholding breastfeeding on the immune response to a live oral rotavirus vaccine in North Indian infants.

    PubMed

    Rongsen-Chandola, Temsunaro; Strand, Tor A; Goyal, Nidhi; Flem, Elmira; Rathore, Sudeep Singh; Arya, Alok; Winje, Brita Askeland; Lazarus, Robin; Shanmugasundaram, Elango; Babji, Sudhir; Sommerfelt, Halvor; Vainio, Kirsti; Kang, Gagandeep; Bhandari, Nita

    2014-08-11

    Interference from transplacental and breast milk antibodies may impede the performance of oral live vaccines. The effect of breastfeeding on the immunogenicity of Rotarix, a two-dose oral monovalent rotavirus vaccine, was examined in a community-based trial in New Delhi, India. Four hundred mother-infant pairs were randomized into two equal groups. Infants were aged 6-7 weeks at enrollment. Mothers were encouraged to either breastfeed or to withhold breastfeeding during the 30 min prior to and after each vaccine dose was administered. We collected blood specimens from infants at enrollment and 4 weeks after the second vaccine dose. Blood and breast milk specimens were obtained from mothers at baseline and breast milk specimens were collected at the time of the second vaccine dose. Seroconversion was defined as infant serum anti-VP6 IgA antibody level of ≥20 IU/mL 4 weeks after the second vaccine dose and a ≥4-fold rise from baseline. There was no difference in the proportion who seroconverted between the two groups (26% vs 27%; p=0.92). The levels of infant serum IgA, maternal serum and breast milk IgA and IgG anti-rotavirus antibodies predicted the anti-rotavirus IgA level in infants at end-study and explained approximately 10% of the variability of the immune response (r(2)=0.10, p<0.001). In this population, the immune response to Rotarix was not enhanced by withholding breastfeeding around the time of vaccination. Maternal anti-rotavirus antibodies explained little of the variability in the immune response to the vaccine. Factors other than maternal anti-rotavirus antibodies probably explain why infants in low-and middle-income settings respond poorly to live oral rotavirus vaccines.

  7. Human peripheral blood CD4+ and CD8+ T cells express Th1-like cytokine mRNA and proteins following in vitro stimulation with heat-inactivated Brucella abortus.

    PubMed Central

    Zaitseva, M B; Golding, H; Betts, M; Yamauchi, A; Bloom, E T; Butler, L E; Stevan, L; Golding, B

    1995-01-01

    Defining the pattern of lymphokine production associated with Brucella abortus is critical for advancing the development of B. abortus as a vaccine carrier. In the present study we investigated the ability of heat-inactivated B. abortus or lipopolysaccharide from B. abortus to induce lymphokine production from purified human T cells in vitro. Gamma interferon (IFN-gamma), interleukin-2 (IL-2), IL-4, and IL-5 induction was assayed by mRNA-specific PCR and by enzyme-linked immunosorbent assay and bioassay for protein production. Following depletion of monocytes and B cells, B. abortus increased IFN-gamma and IL-2 mRNA expression in purified T cells compared with expression in unstimulated cells. In contrast, no IL-5 mRNA expression and only transient low-level IL-4 mRNA expression and no IL-4 protein secretion were detected. Phytohemagglutinin or phorbol myristate acetate plus ionomycin induced mRNA and protein for all these cytokines. Similar results were obtained with LPS purified from B. abortus. Removal of NK cells did not reduce lymphokine production, and enriched NK cells did not express IFN-gamma mRNA or secrete IFN-gamma protein in response to B. abortus, indicating that NK cells were not the responding population. Both CD4+ and CD8+ populations produced IFN-gamma and IL-2 in response to B. abortus. Preincubation of resting T cells with B. abortus or LPS from B. abortus for 7 days induced their differentiation into Th1-like cells as judged by their subsequent lymphokine response to phorbol myristate acetate plus ionomycin. These results suggest that B. abortus can induce differentiation of Th0 into Th1-type cells. PMID:7790090

  8. Live-Attenuated Bacterial Vectors: Tools for Vaccine and Therapeutic Agent Delivery

    PubMed Central

    Lin, Ivan Y. C.; Van, Thi Thu Hao; Smooker, Peter M.

    2015-01-01

    Genetically attenuated microorganisms, including pathogenic and commensal bacteria, can be engineered to carry and deliver heterologous antigens to elicit host immunity against both the vector as well as the pathogen from which the donor gene is derived. These live attenuated bacterial vectors have been given much attention due to their capacity to induce a broad range of immune responses including localized mucosal, as well as systemic humoral and/or cell-mediated immunity. In addition, the unique tumor-homing characteristics of these bacterial vectors has also been exploited for alternative anti-tumor vaccines and therapies. In such approach, tumor-associated antigen, immunostimulatory molecules, anti-tumor drugs, or nucleotides (DNA or RNA) are delivered. Different potential vectors are appropriate for specific applications, depending on their pathogenic routes. In this review, we survey and summarize the main features of the different types of live bacterial vectors and discussed the clinical applications in the field of vaccinology. In addition, different approaches for using live attenuated bacterial vectors for anti-cancer therapy is discussed, and some promising pre-clinical and clinical studies in this field are outlined. PMID:26569321

  9. Temperature-Sensitive Live-Attenuated Canine Influenza Virus H3N8 Vaccine.

    PubMed

    Nogales, Aitor; Rodriguez, Laura; Chauché, Caroline; Huang, Kai; Reilly, Emma C; Topham, David J; Murcia, Pablo R; Parrish, Colin R; Martínez-Sobrido, Luis

    2017-02-15

    Canine influenza is a respiratory disease of dogs caused by canine influenza virus (CIV). CIV subtypes responsible for influenza in dogs include H3N8, which originated from the transfer of H3N8 equine influenza virus to dogs; and the H3N2 CIV, which is an avian-origin virus that adapted to infect dogs. Influenza infections are most effectively prevented through vaccination to reduce transmission and future infection. Currently, only inactivated influenza vaccines (IIVs) are available for the prevention of CIV in dogs. However, the efficacy of IIVs is suboptimal, and novel approaches are necessary for the prevention of disease caused by this canine respiratory pathogen. Using reverse genetics techniques, we have developed a live-attenuated CIV vaccine (LACIV) for the prevention of H3N8 CIV. The H3N8 LACIV replicates efficiently in canine cells at 33°C but is impaired at temperatures of 37 to 39°C and was attenuated compared to wild-type H3N8 CIV in vivo and ex vivo The LACIV was able to induce protection against H3N8 CIV challenge with a single intranasal inoculation in mice. Immunogenicity and protection efficacy were better than that observed with a commercial CIV H3N8 IIV but provided limited cross-reactive immunity and heterologous protection against H3N2 CIV. These results demonstrate the feasibility of implementing a LAIV approach for the prevention and control of H3N8 CIV in dogs and suggest the need for a new LAIV for the control of H3N2 CIV.

  10. Refined live attenuated Salmonella enterica serovar Typhimurium and Enteritidis vaccines mediate homologous and heterologous serogroup protection in mice.

    PubMed

    Tennant, Sharon M; Schmidlein, Patrick; Simon, Raphael; Pasetti, Marcela F; Galen, James E; Levine, Myron M

    2015-12-01

    Invasive nontyphoidal Salmonella (NTS) infections constitute a major health problem among infants and toddlers in sub-Saharan Africa; these infections also occur in infants and the elderly in developed countries. We genetically engineered a Salmonella enterica serovar Typhimurium strain of multilocus sequence type 313, the predominant genotype circulating in sub-Saharan Africa. We evaluated the capacities of S. Typhimurium and Salmonella enterica serovar Enteritidis ΔguaBA ΔclpX live oral vaccines to protect mice against a highly lethal challenge dose of the homologous serovar and determined protection against other group B and D serovars circulating in sub-Saharan Africa. The vaccines S. Typhimurium CVD 1931 and S. Enteritidis CVD 1944 were immunogenic and protected BALB/c mice against 10,000 50% lethal doses (LD50) of S. Typhimurium or S. Enteritidis, respectively. S. Typhimurium CVD 1931 protected mice against the group B serovar Salmonella enterica serovar Stanleyville (91% vaccine efficacy), and S. Enteritidis CVD 1944 protected mice against the group D serovar Salmonella enterica serovar Dublin (85% vaccine efficacy). High rates of survival were observed when mice were infected 12 weeks postimmunization, indicating that the vaccines elicited long-lived protective immunity. Whereas CVD 1931 did not protect against S. Enteritidis R11, CVD 1944 did mediate protection against S. Typhimurium D65 (81% efficacy). These findings suggest that a bivalent (S. Typhimurium and S. Enteritidis) vaccine would provide broad protection against the majority of invasive NTS infections in sub-Saharan Africa.

  11. Refined Live Attenuated Salmonella enterica Serovar Typhimurium and Enteritidis Vaccines Mediate Homologous and Heterologous Serogroup Protection in Mice

    PubMed Central

    Schmidlein, Patrick; Simon, Raphael; Pasetti, Marcela F.; Galen, James E.; Levine, Myron M.

    2015-01-01

    Invasive nontyphoidal Salmonella (NTS) infections constitute a major health problem among infants and toddlers in sub-Saharan Africa; these infections also occur in infants and the elderly in developed countries. We genetically engineered a Salmonella enterica serovar Typhimurium strain of multilocus sequence type 313, the predominant genotype circulating in sub-Saharan Africa. We evaluated the capacities of S. Typhimurium and Salmonella enterica serovar Enteritidis ΔguaBA ΔclpX live oral vaccines to protect mice against a highly lethal challenge dose of the homologous serovar and determined protection against other group B and D serovars circulating in sub-Saharan Africa. The vaccines S. Typhimurium CVD 1931 and S. Enteritidis CVD 1944 were immunogenic and protected BALB/c mice against 10,000 50% lethal doses (LD50) of S. Typhimurium or S. Enteritidis, respectively. S. Typhimurium CVD 1931 protected mice against the group B serovar Salmonella enterica serovar Stanleyville (91% vaccine efficacy), and S. Enteritidis CVD 1944 protected mice against the group D serovar Salmonella enterica serovar Dublin (85% vaccine efficacy). High rates of survival were observed when mice were infected 12 weeks postimmunization, indicating that the vaccines elicited long-lived protective immunity. Whereas CVD 1931 did not protect against S. Enteritidis R11, CVD 1944 did mediate protection against S. Typhimurium D65 (81% efficacy). These findings suggest that a bivalent (S. Typhimurium and S. Enteritidis) vaccine would provide broad protection against the majority of invasive NTS infections in sub-Saharan Africa. PMID:26351285

  12. Phase-I study MEDI-534, of a live, attenuated intranasal vaccine against respiratory syncytial virus and parainfluenza-3 virus in seropositive children.

    PubMed

    Gomez, Margarita; Mufson, Maurice A; Dubovsky, Filip; Knightly, Conor; Zeng, Wen; Losonsky, Genevieve

    2009-07-01

    A live, attenuated respiratory syncytial virus and parainfluenza virus type 3 vaccine was evaluated in healthy respiratory syncytial virus/parainfluenza virus type 3 seropositive children aged 1 to 9 years. Three cohorts of 40 children were randomized 1:1 to receive 10, 10, or 10 median tissue culture infectious dose50 MEDI-534 vaccine or placebo. The vaccine's safety profile was similar to placebo, no viral shedding was detected, and the vaccine was minimally immunogenic.

  13. Factors Related to Pertussis and Tetanus Vaccination Status Among Foreign-Born Adults Living in the United States.

    PubMed

    Sánchez-González, Liliana; Rodriguez-Lainz, Alfonso; O'Halloran, Alissa; Rowhani-Rahbar, Ali; Liang, Jennifer L; Lu, Peng-Jun; Houck, Peter M; Verguet, Stephane; Williams, Walter W

    2016-11-12

    Pertussis is a common vaccine-preventable disease (VPD) worldwide. Its reported incidence has increased steadily in the United States, where it is endemic. Tetanus is a rare but potentially fatal VPD. Foreign-born adults have lower tetanus-diphtheria-pertussis (Tdap) and tetanus-diphtheria (Td) vaccination coverage than do U.S.-born adults. We studied the association of migration-related, socio-demographic, and access-to-care factors with Tdap and Td vaccination among foreign-born adults living in the United States. The 2012 and 2013 National Health Interview Survey data for foreign-born respondents were analyzed. Multivariable logistic regression was conducted to calculate prevalence ratios and 95% confidence intervals, and to identify variables independently associated with Tdap and Td vaccination among foreign-born adults. Tdap and Td vaccination status was available for 9316 and 12,363 individuals, respectively. Overall vaccination coverage was 9.1% for Tdap and 49.8% for Td. Younger age, higher education, having private health insurance (vs. public insurance or uninsured), having visited a doctor in the previous year, and region of residence were independently associated with Tdap and Td vaccination. Among those reporting a doctor visit, two-thirds had not received Tdap. This study provides further evidence of the need to enhance access to health care and immunization services and reduce missed opportunities for Tdap and Td vaccination for foreign-born adults in the United States. These findings apply to all foreign-born, irrespective of their birthplace, citizenship, language and years of residence in the United States. Addressing vaccination disparities among the foreign-born will help achieve national vaccination goals and protect all communities in the United States.

  14. A live-attenuated influenza vaccine for H3N2 canine influenza virus.

    PubMed

    Rodriguez, Laura; Nogales, Aitor; Reilly, Emma C; Topham, David J; Murcia, Pablo R; Parrish, Colin R; Martinez Sobrido, Luis

    2017-04-01

    Canine influenza is a contagious respiratory disease in dogs caused by two subtypes (H3N2 and H3N8) of canine influenza virus (CIV). Currently, only inactivated influenza vaccines (IIVs) are available for the prevention of CIVs. Historically, live-attenuated influenza vaccines (LAIVs) have been shown to produce better immunogenicity and protection efficacy than IIVs. Here, we have engineered a CIV H3N2 LAIV by using the internal genes of a previously described CIV H3N8 LAIV as a master donor virus (MDV) and the surface HA and NA genes of a circulating CIV H3N2 strain. Our findings show that CIV H3N2 LAIV replicates efficiently at low temperature but its replication is impaired at higher temperatures. The CIV H3N2 LAIV was attenuated in vivo but induced better protection efficacy in mice against challenge with wild-type CIV H3N2 than a commercial CIV H3N2 IIV. This is the first description of a LAIV for the prevention of CIV H3N2 in dogs.

  15. Development of live-attenuated arenavirus vaccines based on codon deoptimization of the viral glycoprotein

    PubMed Central

    Cheng, Benson Y.H.; Nogales, Aitor; de la Torre, Juan Carlos; Martínez-Sobrido, Luis

    2016-01-01

    Several arenaviruses, chiefly Lassa (LASV) in West Africa, cause hemorrhagic fever (HF) disease in humans and pose important public health problems in their endemic regions. To date, there are no FDA-approved arenavirus vaccines and current anti-arenaviral therapy is limited to the use of ribavirin that has very limited efficacy. In this work we dcument that a recombinant prototypic arenavirus lymphocytic choriomeningitis virus (LCMV) with a codon deoptimized (CD) surface glycoprotein (GP), rLCMV/CD, exhibited wild type (WT)-like growth properties in cultured cells despite barely detectable GP expression levels in rLCMV/CD-infected cells. Importantly, rLCMV/CD was highly attenuated in vivo but able to induce complete protection against a subsequent lethal challenge with rLCMV/WT. Our findings support the feasibility of implementing an arenavirus GP CD-based approach for the development of safe and effective live-attenuated vaccines (LAVs) to combat diseases caused by human pathogenic arenaviruses. PMID:27855284

  16. A new approach to an influenza live vaccine: modification of the cleavage site of hemagglutinin.

    PubMed

    Stech, J; Garn, H; Wegmann, M; Wagner, R; Klenk, H-D

    2005-06-01

    A promising approach to reduce the impact of influenza is the use of an attenuated, live virus as a vaccine. Using reverse genetics, we generated a mutant of strain A/WSN/33 with a modified cleavage site within its hemagglutinin, which depends on proteolytic activation by elastase. Unlike the wild-type, which requires trypsin, this mutant is strictly dependent on elastase. Both viruses grow equally well in cell culture. In contrast to the lethal wild-type virus, the mutant is entirely attenuated in mice. At a dose of 10(5) plaque-forming units, it induced complete protection against lethal challenge. This approach allows the conversion of any epidemic strain into a genetically homologous attenuated virus.

  17. Live Vaccine Strain Francisella tularensis is Detectable at the Inoculation Site but Not in Blood after Vaccination Against Tularemia

    DTIC Science & Technology

    2006-08-10

    The culture and PCR results of all blood samples were negative. Results of real - time PCR from the inoculation site samples were positive for 41 (100...LVS vaccination, with real - time PCR being more sensitive than culture. Our data suggest that bacteremia does not occur after LVS vaccination in normal, healthy human volunteers.

  18. Safety and immunogenicity of a live-attenuated auxotrophic candidate vaccine against the intracellular pathogen Rhodococcus equi.

    PubMed

    Lopez, A M; Townsend, H G G; Allen, A L; Hondalus, M K

    2008-02-13

    Rhodococcus equi causes serious pneumonia in neonatal foals and is an opportunistic pathogen of people with compromised cellular immunity. No effective vaccine against R. equi disease in foals is available. We tested the safety and immunogenicity of a live, fully attenuated riboflavin auxotrophic candidate vaccine strain of R. equi (R. equi rib-). We demonstrated that R. equi rib- is immunogenic and capable of inducing IFN-gamma responses in immunocompetent BALB/c mice, yet it is safe even in an immunocompromised SCID mouse infection model. Moreover, it protects immunocompetent mice against virulent R. equi challenge. In foals, R. equi rib- was likewise safe and stimulated serum R. equi-specific immune responses. A preliminary immunization strategy did not afford protection against virulent R. equi challenge and therefore, optimization of the vaccine formulation and or vaccination protocol will be necessary.

  19. Protective efficacy of a live attenuated Mycoplasma hyopneumoniae vaccine with an ISCOM-matrix adjuvant in pigs.

    PubMed

    Xiong, Qiyan; Wei, Yanna; Feng, Zhixin; Gan, Yuan; Liu, Zhanjun; Liu, Maojun; Bai, Fangfang; Shao, Guoqing

    2014-02-01

    An attenuated Mycoplasma hyopneumoniae vaccine that requires intrathoracic administration is commercially available for use against mycoplasmal pneumonia in China. Given the limitations of such a route of administration, this study was undertaken to assess the capacity of an ISCOM-matrix adjuvant to enhance immunogenicity following intramuscular use. Immune responses in pigs following vaccination and subsequent intra-tracheal bacterial inoculation were examined using lymphocyte proliferation, serology and mucosal IgA in both nasal and saliva swabs. Vaccination induced clear lymphocyte proliferation, but only slight serum antibody responses although these were significantly increased following experimental infection. Mucosal IgA was not detected in either nasal or salivary secretions. Following bacterial challenge, animals vaccinated with the adjuvant-containing live vaccine exhibited less severe pulmonary lesions (median score 3.67) than unvaccinated pigs (median score 13.58). The degree of ciliary loss on the respiratory tract surface was reduced in vaccinated pigs compared with experimentally infected controls. The findings indicated that the adjuvant vaccine administered IM provided protection against experimentally induced mycoplasmal pneumonia and could have commercial potential.

  20. Rabies challenge of captive striped skunks (Mephitis mephitis) following oral administration of a live vaccinia-vectored rabies vaccine.

    PubMed

    Grosenbaugh, Deborah A; Maki, Joanne L; Rupprecht, Charles E; Wall, Debra K

    2007-01-01

    Twenty-four adult striped skunks (Mephitis mephitis) were administered the raccoon product formulation of Rabies Vaccine, Live Vaccinia-Vectored (Raboral V-RG, Merial Limited, Athens, Georgia, USA), either by oral instillation or in vaccine-filled coated sachets either as single or multiple doses. A control group remained unvaccinated. Twenty-three of the skunks were challenged 116 days postvaccination with rabies virus (skunk isolate). Six of six naive skunks succumbed to challenge. Four of six skunks that received the vaccine by oral instillation survived challenge. The skunks that did not survive failed to seroconvert following vaccination. None of the skunks that accepted multiple doses of the vaccine offered in coated sachets survived challenge, nor were rabies virus-neutralizing antibodies (VNAs) detected in the sera. Likewise, none of the five skunks ingesting a single sachet developed VNA against rabies. However, in this group one skunk did survive rabies challenge. This preliminary study showed that the vaccinia-vectored oral rabies vaccine Raboral V-RG, as formulated for use in raccoons, is capable of protecting a percentage of skunks against rabies. However, although the fishmeal-coated sachets were readily consumed, subsequent challenge of these animals revealed poor vaccine delivery efficiency.

  1. Evaluation of transmission of Brucella abortus strain 19 in bison by intravaginal, intrauterine, and intraconjunctival inoculation.

    PubMed

    Uhrig, Samantha R; Nol, Pauline; McCollum, Matt; Salman, Mo; Rhyan, Jack C

    2013-07-01

    Bovine brucellosis, caused by the bacterium Brucella abortus, is endemic in bison (Bison bison) and elk (Cervus elaphus nelsoni) populations in the area of Yellowstone National Park, USA. Two strategies have been proposed to reduce the risk of transmission of disease in bison: remote vaccination with the vaccine RB51, and the use of immunocontraception of bison to decrease shedding of organisms from infected females. The frequent occurrence of venereal transmission in bison would complicate either of these strategies, requiring vaccination of males as well as females, and rendering immunocontraception less effective in reducing transmission of B. abortus. To address the question of venereal transmission, we inoculated each of 18 bison cows with 4.5 × 10(8) colony-forming units of B. abortus strain 19, as a surrogate of field strain, by three routes: intraconjunctival (IC), intravaginal (VI), and intracervical/intrauterine (AI). Bison semen was mixed with strain 19 inoculum for the latter route. Bison were monitored by serology and culture for 12 wk, at which time they were euthanized and specimens collected for culture. All IC-inoculated animals seroconverted on multiple tests and one was culture positive at 12 wk postexposure. Seven of eight VI bison developed suspect or positive serologic tests and four were positive at one or more time points. Weak transient serologic responses (suspect) were seen in four of five AI bison. Results showed that IC inoculation with strain 19 was a suitable surrogate for field strain to demonstrate exposure to the B. abortus. The seroconversion of four of eight VI bison indicated exposure of the immune system to the agent and the need for further studies on venereal transmission in bison.

  2. Qualitative differences in the early immune response to live and killed Leishmania major: Implications for vaccination strategies against Leishmaniasis.

    PubMed

    Okwor, Ifeoma; Liu, Dong; Uzonna, Jude

    2009-04-28

    Recovery from natural or deliberate infection with Leishmania major leads to the development of lifelong immunity against rechallenge infections. In contrast, vaccination with killed parasites or defined leishmanial antigens generally induces only short-term protection. The reasons for this difference are currently not known but may be related to differences in the quality of the early immune responses to live and killed parasites. Here, we report that live and killed L. major parasites elicit comparable early inflammatory response as evidenced by influx and/or proliferation of cells in the draining lymph nodes (dLNs). In contrast, the early cytokine responses were qualitatively different. Cells from mice inoculated with killed parasites produced significantly more antigen-specific IL-4 and less IFN-gamma than those from mice injected with live parasites. Inclusion of CpG ODN into killed parasite preparations changed the early response to killed parasites from IL-4 to a predominantly IFN-gamma response, resulting in better protection following secondary high dose virulent L. major challenge. Interestingly, CpG-mediated enhancement of killed parasites-induced protection was short-lived and waned after 12 weeks. Taken together, these results suggest that the nature of primary immunity induced by killed and live parasites are qualitatively different and that these differences may account for the differential protection seen in mice following vaccination with live and killed parasites. They further suggest that modulating the early response with an appropriate adjuvant could enhance efficacy of killed parasite vaccines.

  3. Live attenuated measles and mumps viral strain-containing vaccines and hearing loss: Vaccine Adverse Event Reporting System (VAERS), United States, 1990--2003.

    PubMed

    Asatryan, Armenak; Pool, Vitali; Chen, Robert T; Kohl, Katrin S; Davis, Robert L; Iskander, John K

    2008-02-26

    Hearing loss (HL) is a known complication of wild measles and mumps viral infections. As vaccines against measles and mumps contain live attenuated viral strains, it is biologically plausible that in some individuals HL could develop as a complication of vaccination against measles and/or mumps. Our objectives for this study were: to find and describe all cases of HL reported in the scientific literature and to the US Vaccine Adverse Events Reporting System (VAERS) for the period 1990--2003; and to determine reporting rate of HL after live attenuated measles and/or mumps viral strain-containing vaccines (MMCV) administration. We searched published reports for cases of HL identified after vaccination with MMCV. We also searched for reports of HL after MMCV administration submitted to VAERS from 1990 through 2003 and determined the dose-adjusted reporting rate of HL. Our main outcome measure was reported cases of HL after immunization with MMCV which were classified as idiopathic. We found 11 published case reports of HL following MMCV. The review of the VAERS reports identified 44 cases of likely idiopathic sensorineural HL after MMCV administration. The onset of HL in the majority of VAERS and published cases was consistent with the incubation periods of wild measles and mumps viruses. Based on the annual usage of measles-mumps-rubella (MMR) vaccine, we estimated the reporting rate of HL to be 1 case per 6-8 million doses. Thus, HL following MMCV has been reported in the literature and to the VAERS. Further studies are needed to better understand if there is a causal relationship between MMCV and HL.

  4. Infection and transmission of live recombinant Newcastle disease virus vaccines in Rock Pigeons, European House Sparrows, and Japanese Quail

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In China and Mexico, engineered recombinant Newcastle disease virus (rNDV) strains are used as live vaccines for the control of Newcastle disease and as vectors to express the avian influenza virus hemagglutinin (HA) gene to control avian influenza in poultry. In this study, non-target species wer...

  5. Attempt to develop live attenuated bacterial vaccines by selecting resistance to gossypol, proflavine hemisulfate, novobiocin, or ciprofloxacin

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In an attempt to develop attenuated bacteria as potential live vaccines, four chemicals (gossypol, proflavine hemisulfate, novobiocin, and ciprofloxacin) were used to modify the following four genera of bacteria through chemical-resistance strategy: 1) Aeromonas hydrophila (9 isolates); 2) Edwardsie...

  6. Attempt to develop live attenuated bacterial vaccines by selecting resistance to gossypol, proflavine hemisulfate, novobiocin, or ciprofloxacin

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In an attempt to develop attenuated bacteria as potential live vaccines, four chemicals (gossypol, proflavine hemisulfate, novobiocin, and ciprofloxacin) were used to modify the following four genera of bacteria through chemical-resistance strategy: (1) Aeromonas hydrophila (9 isolates); (2) Edwards...

  7. Evaluation of eight live attenuated vaccine candidates for protection against challenge with virulent Mycobacterium avium subspecies paratuberculosis in mice

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Johne’s disease is caused by Mycobacterium avium subsp. paratuberculosis (MAP), which results in serious economic losses worldwide in farmed livestock such as cattle, sheep and goats. To control this disease, an effective vaccine with minimal adverse effects is needed. In order to identify a live va...

  8. A reassortment-incompetent live attenuated influenza virus vaccine for use in protection against pandemic virus strains

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Although live-attenuated influenza vaccines (LAIV) are safe for use in protection against seasonal influenza strains, concerns over their potential to reassort with wild-type virus strains have been voiced. LAIVs have been demonstrated to induce enhanced mucosal and cell-mediated immunity over inac...

  9. General Molecular Strategy for Development of Arenavirus Live-Attenuated Vaccines

    PubMed Central

    Iwasaki, Masaharu; Ngo, Nhi; Cubitt, Beatrice; Teijaro, John R.

    2015-01-01

    ABSTRACT Hemorrhagic fever arenaviruses (HFA) pose important public health problems in regions where they are endemic. Thus, Lassa virus (LASV) infects several hundred thousand individuals yearly in West Africa, causing a large number of Lassa fever cases associated with high morbidity and mortality. Concerns about human-pathogenic arenaviruses are exacerbated because of the lack of FDA-licensed arenavirus vaccines and because current antiarenaviral therapy is limited to an off-label use of ribavirin that is only partially effective. The Mopeia virus (MOPV)/LASV reassortant (ML29) is a LASV candidate live-attenuated vaccine (LAV) that has shown promising results in animal models. Nevertheless, the mechanism of ML29 attenuation remains unknown, which raises concerns about the phenotypic stability of ML29 in response to additional mutations. Development of LAVs based on well-defined molecular mechanisms of attenuation will represent a major step in combatting HFA. We used the prototypic arenavirus lymphocytic choriomeningitis virus (LCMV) to develop a general molecular strategy for arenavirus attenuation. Our approach involved replacement of the noncoding intergenic region (IGR) of the L genome segment with the IGR of the S genome segment to generate a recombinant LCMV, rLCMV(IGR/S-S), that was highly attenuated in vivo but induced protection against a lethal challenge with wild-type LCMV. Attenuation of rLCMV(IGR/S-S) was associated with a stable reorganization of the control of viral gene expression. This strategy can facilitate the rapid development of LAVs with the antigenic composition of the parental HFA and a mechanism of attenuation that minimizes concerns about increased virulence that could be caused by genetic changes in the LAV. IMPORTANCE Hemorrhagic fever arenaviruses (HFA) cause high morbidity and mortality, and pose important public health problems in the regions where they are endemic. Implementation of live-attenuated vaccines (LAV) will represent a

  10. Comparison of the protective efficacies of the live vaccine RIT 4025 and an inactivated vaccine against a natural heterologous A/Victoria/3/75 infection.

    PubMed

    Delem, A; Van Rensburg, W; Flaskett, I

    1979-10-01

    A clinical trial was initiated in South Africa before the winter season of 1976. The study involved 253 volunteers divided into three groups of vaccinees and one control group. Two groups of vaccinees were inoculated with either one or two doses at 2 weeks' interval (10(7.2) EID 50/dose) of the RIT 4025 live recombinant strain [A/Scotland/840/74 (H3N2) serotype] and one group received one injection of an inactivated vaccine [A/Port Chalmers/1/73 (H3N2), 360 i.u., A/Scotland/840/74 (H3N2), 300 i.u. and B/Hong Kong/8/73, 300 i.u./dose]. The serum antihaemagglutinin antibody responses against the heterologous A/Victoria/3/75 strain as measured by the single radial haemolysis test were satisfactory and not statistically different in all groups of vaccinees. On the other hand, the antineuraminidase antibody response was better in the group receiving the killed vaccine. At the end of the influenza season, A/Victoria/3/75 infections were confirmed serologically. Only 12% of the infections were symptomatic. The infection rate was significantly reduced in the live vaccine groups, whereas in the killed vaccine group the percentage of infection was lower but not significantly different from that in the placebo group.

  11. Feline panleukopenia virus, feline herpesvirus-1 and feline calicivirus antibody responses in seronegative specific pathogen-free kittens after parenteral administration of an inactivated FVRCP vaccine or a modified live FVRCP vaccine.

    PubMed

    Lappin, Michael R

    2012-02-01

    Two groups of feline panleukopenia (FPV), feline calicivirus (FCV) and feline herpesvirus 1 (FHV-1) seronegative kittens (six cats per group) were administered one of two feline viral rhinotracheitis, calcivirus and panleukopenia (FVRCP) vaccines subcutaneously (one inactivated and one modified live) and the serological responses to each agent were followed over 49 days (days 0, 2, 5, 7, 10, 14, 21, 28, 35, 42, 49). While the kittens administered the modified live FPV vaccine were more likely to seroconvert on day 7 after the first inoculation than kittens administered the inactivated vaccine, all kittens had seroconverted by day 14. In contrast, FHV-1 serological responses were more rapid following administration of the inactivated FVRCP vaccine when compared with the modified live FVRCP vaccine. There were no statistical differences between the serological response rates between the two FVRCP vaccines in regard to FCV.

  12. Intranasal Infection with Chlamydia abortus Induces Dose-Dependent Latency and Abortion in Sheep

    PubMed Central

    Longbottom, David; Livingstone, Morag; Maley, Stephen; van der Zon, Arjan; Rocchi, Mara; Wilson, Kim; Wheelhouse, Nicholas; Dagleish, Mark; Aitchison, Kevin; Wattegedera, Sean; Nath, Mintu; Entrican, Gary; Buxton, David

    2013-01-01

    Background Latency is a key feature of the animal pathogen Chlamydia abortus, where infection remains inapparent in the non-pregnant animal and only becomes evident during a subsequent pregnancy. Often the first sign that an animal is infected is abortion occurring late in gestation. Despite this, little is understood of the underlying mechanisms that control latency or the recrudescence of infection that occurs during subsequent pregnancy. The aim of this study was to develop an experimental model of latency by mimicking the natural route of infection through the intranasal inoculation of non-pregnant sheep with C. abortus. Methodology/Principal Findings Three groups of sheep (groups 1, 2 and 3) were experimentally infected with different doses of C. abortus (5×103, 5×105 and 5×107 inclusion forming units (IFU), respectively) prior to mating and monitored over 2 breeding cycles for clinical, microbiological, pathological, immunological and serological outcomes. Two further groups received either negative control inoculum (group 4a,b) or were inoculated subcutaneously on day 70 of gestation with 2×106 IFU C. abortus (group 5). Animals in groups 1, 2 and 5 experienced an abortion rate of 50–67%, while only one animal aborted in group 3 and none in group 4a,b. Pathological, microbiological, immunological and serological analyses support the view that the maternal protective immune response is influenced by initial exposure to the bacterium. Conclusions/Significance The results show that intranasal administration of non-pregnant sheep with a low/medium dose of C. abortus results in a latent infection that leads in a subsequent pregnancy to infection of the placenta and abortion. In contrast a high dose stimulates protective immunity, resulting in a much lower abortion rate. This model will be useful in understanding the mechanisms of infection underlying latency and onset of disease, as well as in the development of novel therapeutics and vaccines for

  13. Vaccines

    MedlinePlus Videos and Cool Tools

    Vaccinations are injections of antigens into the body. Once the antigens enter the blood, they circulate along ... suppressor T cells stop the attack. After a vaccination, the body will have a memory of an ...

  14. Serologic responses after vaccination of fennec foxes (Vulpes zerda) and meerkats (Suricata suricatta) with a live, canarypox-vectored canine distemper virus vaccine.

    PubMed

    Coke, Rob L; Backues, Kay A; Hoover, John P; Saliki, Jeremiah T; Ritchey, Jerry W; West, Gary D

    2005-06-01

    Fennec foxes (Vulpes zerda) and meerkats (Suricata suricatta) are considered to be susceptible to canine distemper virus (CDV) infection. Although no definitive clinical cases of natural CDV infections have been reported, mortalities due to CDV have been suspected and are reported in other closely related species. A commercially available monovalent, live, canarypox-vectored CDV vaccine induced neutralizing antibody titers that were maintained for at least a year in both fennec foxes and meerkats.

  15. A Phase II, Randomized, Safety and Immunogenicity Trial of a Re-Derived, Live-Attenuated Dengue Virus Vaccine in Healthy Children and Adults Living in Puerto Rico

    PubMed Central

    Bauer, Kristen; Esquilin, Ines O.; Cornier, Alberto Santiago; Thomas, Stephen J.; Quintero del Rio, Ana I.; Bertran-Pasarell, Jorge; Morales Ramirez, Javier O.; Diaz, Clemente; Carlo, Simon; Eckels, Kenneth H.; Tournay, Elodie; Toussaint, Jean-Francois; De La Barrera, Rafael; Fernandez, Stefan; Lyons, Arthur; Sun, Wellington; Innis, Bruce L.

    2015-01-01

    This was a double-blind, randomized, controlled, phase II clinical trial, two dose study of re-derived, live-attenuated, tetravalent dengue virus (TDEN) vaccine (two formulations) or placebo in subjects 1–50 years of age. Among the 636 subjects enrolled, 331 (52%) were primed, that is, baseline seropositive to at least one dengue virus (DENV) type. Baseline seropositivity prevalence increased with age (10% [< 2 years], 26% [2–4 years], 60% [5–20 years], and 93% [21–50 years]). Safety profiles of TDEN vaccines were similar to placebo regardless of priming status. No vaccine-related serious adverse events (SAEs) were reported. Among unprimed subjects, immunogenicity (geometric mean antibody titers [GMT] and seropositivity rates) for each DENV increased substantially in both TDEN vaccine groups with at least 74.6% seropositive for four DENV types. The TDEN vaccine candidate showed an acceptable safety and immunogenicity profile in children and adults ranging from 1 to 50 years of age, regardless of priming status. ClinicalTrials.gov: NCT00468858. PMID:26175027

  16. A Phase II, Randomized, Safety and Immunogenicity Trial of a Re-Derived, Live-Attenuated Dengue Virus Vaccine in Healthy Children and Adults Living in Puerto Rico.

    PubMed

    Bauer, Kristen; Esquilin, Ines O; Cornier, Alberto Santiago; Thomas, Stephen J; Quintero Del Rio, Ana I; Bertran-Pasarell, Jorge; Morales Ramirez, Javier O; Diaz, Clemente; Carlo, Simon; Eckels, Kenneth H; Tournay, Elodie; Toussaint, Jean-Francois; De La Barrera, Rafael; Fernandez, Stefan; Lyons, Arthur; Sun, Wellington; Innis, Bruce L

    2015-09-01

    This was a double-blind, randomized, controlled, phase II clinical trial, two dose study of re-derived, live-attenuated, tetravalent dengue virus (TDEN) vaccine (two formulations) or placebo in subjects 1-50 years of age. Among the 636 subjects enrolled, 331 (52%) were primed, that is, baseline seropositive to at least one dengue virus (DENV) type. Baseline seropositivity prevalence increased with age (10% [< 2 years], 26% [2-4 years], 60% [5-20 years], and 93% [21-50 years]). Safety profiles of TDEN vaccines were similar to placebo regardless of priming status. No vaccine-related serious adverse events (SAEs) were reported. Among unprimed subjects, immunogenicity (geometric mean antibody titers [GMT] and seropositivity rates) for each DENV increased substantially in both TDEN vaccine groups with at least 74.6% seropositive for four DENV types. The TDEN vaccine candidate showed an acceptable safety and immunogenicity profile in children and adults ranging from 1 to 50 years of age, regardless of priming status. ClinicalTrials.gov: NCT00468858.

  17. African horse sickness in The Gambia: circulation of a live-attenuated vaccine-derived strain.

    PubMed

    Oura, C A L; Ivens, P A S; Bachanek-Bankowska, K; Bin-Tarif, A; Jallow, D B; Sailleau, C; Maan, S; Mertens, P C; Batten, C A

    2012-03-01

    African horse sickness virus serotype 9 (AHSV-9) has been known for some time to be circulating amongst equids in West Africa without causing any clinical disease in indigenous horse populations. Whether this is due to local breeds of horses being resistant to disease or whether the AHSV-9 strains circulating are avirulent is currently unknown. This study shows that the majority (96%) of horses and donkeys sampled across The Gambia were seropositive for AHS, despite most being unvaccinated and having no previous history of showing clinical signs of AHS. Most young horses (<3 years) were seropositive with neutralizing antibodies specific to AHSV-9. Eight young equids (<3 years) were positive for AHSV-9 by serotype-specific RT-PCR and live AHSV-9 was isolated from two of these horses. Sequence analysis revealed the presence of an AHSV-9 strain showing 100% identity to Seg-2 of the AHSV-9 reference strain, indicating that the virus circulating in The Gambia was highly likely to have been derived from a live-attenuated AHSV-9 vaccine strain.

  18. Efficacy of a live glycoprotein E-negative bovine herpesvirus 1 vaccine in cattle in the field.

    PubMed

    Mars, M H; de Jong, M C; Franken, P; van Oirschot, J T

    2001-02-28

    To assess the efficacy of a live glycoprotein E-negative bovine herpesvirus 1 (BHV1) vaccine to reduce transmission of BHV1 in cattle, a randomised, double-blind, placebo-controlled field trial including 84 herds was conducted in the Netherlands. The incidence of BHV1 infections during 17 months was monitored by detecting antibodies against BHV1 glycoprotein E. In the placebo-treated group 214 seroconversions in 3985 paired sera, and in the vaccinated group 67 seroconversions in 3601 paired sera were detected. Based on these data, the transmission ratio R(0) was estimated for each treatment, using the maximum likelihood approach and the martingale approach. In placebo-treated herds R(0) was 2.5 (CI 1.4-3.1) using maximum likelihood and 2.8 (S.E. 0.4) using the martingale approach. In the vaccinated group these estimations were 1.2 (CI 0.5-1.5) and 1.5 (S.E. 0.4) respectively. The vaccinated and placebo-treated group differed significantly in transmission of BHV1. These results suggest that the use of this live gE-negative BHV1 vaccine will reduce the incidence and transmission of BHV1 infections in the field.

  19. Identification of a protective protein from stationary-phase exoproteome of Brucella abortus.

    PubMed

    Jain, Shikha; Kumar, Subodh; Dohre, Sudhir; Afley, Prachiti; Sengupta, Nabonita; Alam, Syed I

    2014-02-01

    Brucellosis is a worldwide zoonotic disease. No Brucella vaccine is available for use in humans, and existing animal vaccines have limitations. To search the putative vaccine candidates, we studied the exoproteome of Brucella abortus NCTC 10093 using 2-DE-MS approach. Twenty-six proteins were identified using MALDI-TOF/TOF tandem mass spectrometry. Outer membrane protein 25, d-galactose periplasmic-binding protein, oligopeptide ABC transporter protein and isopropylmalate synthase were found to be the most abundant proteins. Most proteins (6, 23%) were predicted to be involved in amino acid transport and metabolism followed by carbohydrate transport and metabolism (4, 15%). Outer membrane protein 25, Omp2b porin and one hypothetical protein were predicted as outer membrane proteins. In addition, Omp28, Omp31 and one ribosomal protein (L9) were also identified. The ribosomal protein L9 was produced as a recombinant protein and was studied in mouse model for vaccine potential. It was found to be immunogenic in terms of generating serum antibody response and release of IFN-γ from mice spleen cells. Recombinant L9-immunized mice were protected against challenge with virulent B. abortus strain 544, suggesting usefulness of ribosomal protein L9 as a good vaccine candidate against brucellosis.

  20. Persistence of cell-mediated immunity three decades after vaccination with the live vaccine strain of Francisella tularensis

    PubMed Central

    Eneslätt, Kjell; Rietz, Cecilia; Rydén, Patrik; Stöven, Svenja; House, Robert V.; Wolfraim, Lawrence A.; Tärnvik, Arne; Sjöstedt, Anders

    2012-01-01

    Summary The efficacy of many vaccines against intracellular bacteria depends on the generation of cell-mediated immunity, but studies to determine the duration of immunity are usually confounded by re-exposure. The causative agent of tularemia, Francisella tularensis, is rare in most areas and, therefore, tularemia vaccination is an interesting model for studies of the longevity of vaccine-induced cell-mediated immunity. Here lymphocyte proliferation and cytokine production in response to F. tularensis were assayed in two groups of 16 individuals, vaccinated 1-3 or 27-34 years previously. As compared to naïve individuals, vaccinees of both groups showed higher proliferative responses and, out of 17 cytokines assayed, higher levels of MIP-1β, IFN-γ, IL-10, and IL-5 in response to recall stimulation. The responses were very similar in the two groups of vaccinees. A statistical model was developed to predict the immune status of the individuals and by use of two parameters, proliferative responses and levels of IFN-γ, 91.1% of the individuals were correctly classified. Using flow cytometry analysis, we demonstrated that during recall stimulation, expression of IFN-γ by CD4+CCR7+, CD4+CD62L+, CD8+CCR7+, and CD8+CD62L+ cells significantly increased in samples from vaccinated donors. In conclusion, cell-mediated immunity was found to persist three decades after tularemia vaccination without evidence of decline. PMID:21442618

  1. Assessment of protective efficacy of live and killed vaccines based on a non-encapsulated mutant of Streptococcus suis serotype 2.

    PubMed

    Wisselink, Henk J; Stockhofe-Zurwieden, Norbert; Hilgers, Luuk A T; Smith, Hilde E

    2002-01-03

    The protective efficacy of a live and killed non-encapsulated isogenic mutant of Streptococcus suis serotype 2 was determined in pigs, and compared with the efficacy of the capsulated wild-type strain. SPF pigs were vaccinated twice intramuscularly at 4 and 7 weeks of age with a dose of 1 x 10(9) formalin-killed CFU of the wild-type (WT-BAC), formalin-killed non-encapsulated mutant (CM-BAC) or live non-encapsulated mutant (CM-LIVE) strain. After 2 weeks, vaccinated pigs and non-vaccinated controls were challenged intravenously with 1 x 10(7) CFU of the homologous, wild-type S. suis serotype 2 strain. Protection was evaluated by clinical, bacteriological, serological and post-mortem examinations. All pigs vaccinated with WT-BAC were completely protected against challenge with the homologous serotype. Pigs vaccinated with CM-BAC were partially protected. Although all pigs vaccinated with CM-BAC survived the challenge, four out of five pigs developed clinical signs of disease for several days. Compared to the WT-BAC and CM-BAC, the CM-LIVE vaccine was less protective. Two out of five pigs vaccinated with CM-LIVE died in the course of the experiment and all of them developed specific clinical signs of disease for several days. The protective efficacy of the vaccines could be associated with serum antibody titers. Antibody titers against cells of wild-type and non-encapsulated mutant strains as well as against muramidase-released proteins (MRP) were high in pigs vaccinated with WT-BAC and CM-BAC. Pigs vaccinated with CM-LIVE showed lower antibody titers. Antibody titers against purified capsular polysaccharides (CPS) of S. suis serotype 2 were only found in pigs vaccinated with WT-BAC. These findings indicate that CPS and other bacterial components of WT-BAC are probably essential for full protection against homologous challenge.

  2. Recent advances in the study of live attenuated cell-cultured smallpox vaccine LC16m8.

    PubMed

    Eto, Akiko; Saito, Tomoya; Yokote, Hiroyuki; Kurane, Ichiro; Kanatani, Yasuhiro

    2015-11-09

    LC16m8 is a live, attenuated, cell-cultured smallpox vaccine that was developed and licensed in Japan in the 1970s, but was not used in the campaign to eradicate smallpox. In the early 2000s, the potential threat of bioterrorism led to reconsideration of the need for a smallpox vaccine. Subsequently, LC16m8 production was restarted in Japan in 2002, requiring re-evaluation of its safety and efficacy. Approximately 50,000 children in the 1970s and about 3500 healthy adults in the 2000s were vaccinated with LC16m8 in Japan, and 153 adults have been vaccinated with LC16m8 or Dryvax in phase I/II clinical trials in the USA. These studies confirmed the safety and efficacy of LC16m8, while several studies in animal models have shown that LC16m8 protects the host against viral challenge. The World Health Organization Strategic Advisory Group of Experts on Immunization recommended LC16m8, together with ACAM2000, as a stockpile vaccine in 2013. In addition, LC16m8 is expected to be a viable alternative to first-generation smallpox vaccines to prevent human monkeypox.

  3. Influence of antibiotics used as feed additives on the immune effect of erysipelas live vaccine in swine.

    PubMed

    Yamamoto, K; Takagi, M; Endoh, Y S; Kijima, M; Takahashi, T

    2000-08-01

    To investigate the influence of antibiotics used as feed additives on the immune response to erysipelas live vaccine, the pig inoculation test was applied. Avilamycin, oxytetracycline quaternary salt, enramycin, virginiamycin and tylosin phosphate were selected as test antibiotics. Five experimental feeds containing each antibiotic at the highest concentration permitted for feed additives in Japan, and the basal diet lacking antibiotics were examined. Twenty-nine pigs were divided into six groups. At first all the groups were fed with the antibiotic-free basal diet for 7 days, and then each group received the experimental feeds. On the 14th day after feeding with test feeds all the pigs, except for one control pig in each group, were immunized with the vaccine and all the pigs were then challenge-exposed to a virulent strain of Erysipelothrix rhusiopathiae 14 days after vaccination. The clinical response was observed every day for 14 days. In all the groups, most of the vaccinated pigs did not develop any clinical signs of acute erysipelas after the challenge exposure, whereas non-vaccinated control pigs died or showed severe generalized erythema with profound depression and anorexia. No differences in the protection against the challenge exposure were observed among the groups. Therefore, the present results suggest that these selected antibiotics would not interfere with the immune effect of the vaccine if given at the usual concentrations used for feed additives.

  4. Pheno- and genotyping of Brucella abortus biovar 5 isolated from a water buffalo (Bubalus bubalis) fetus: First case reported in the Americas.

    PubMed

    Martínez, Diana; Thompson, Carolina; Draghi, Graciela; Canavesio, Vilma; Jacobo, Roberto; Zimmer, Patricia; Elena, Sebastián; Nicola, Ana M; de Echaide, Susana Torioni

    2014-09-17

    An isolate of Brucella spp. from an aborted water buffalo (Bubalus bubalis) fetus was characterized based on its pheno- and genotype. The phenotype was defined by carbon dioxide requirement, hydrogen sulfide production, sensitivity to thionin and basic fuchsin and agglutination with Brucella A and M monospecific antisera. The genotype was based on the amplification of the following genes: bcsp31, omp2ab, and eri and the species-specific localization of the insertion sequence IS711 in the Brucella chromosome via B. abortus-B. melitensis-B. ovis-B. suis (AMOS)-PCR. Unexpectedly, the isolate showed a phenotype different from B. abortus bv 1, the most prevalent strain in cattle in Argentina, and from vaccine strain 19, currently used in bovines and water buffaloes. Genotyping supported the phenotypic results, as the analysis of the omp2ab gene sequence showed an identical pattern to either B. abortus bv 5 or B. melitensis. Finally, the AMOS PCR generated a 1700-bp fragment from the isolate, different than those amplified from B. abortus bv 1 (498bp) and B. melitensis (731bp), confirming the presence of B. abortus bv 5. The OIE/FAO Reference Laboratory for Brucellosis confirmed this typing. This is the first report of B. abortus bv 5 from a water buffalo in the Americas.

  5. A Live Attenuated Equine H3N8 Influenza Vaccine Is Highly Immunogenic and Efficacious in Mice and Ferrets

    PubMed Central

    Baz, Mariana; Paskel, Myeisha; Matsuoka, Yumiko; Zengel, James; Cheng, Xing; Treanor, John J.; Jin, Hong

    2014-01-01

    ABSTRACT Equine influenza viruses (EIV) are responsible for rapidly spreading outbreaks of respiratory disease in horses. Although natural infections of humans with EIV have not been reported, experimental inoculation of humans with these viruses can lead to a productive infection and elicit a neutralizing antibody response. Moreover, EIV have crossed the species barrier to infect dogs, pigs, and camels and therefore may also pose a threat to humans. Based on serologic cross-reactivity of H3N8 EIV from different lineages and sublineages, A/equine/Georgia/1/1981 (eq/GA/81) was selected to produce a live attenuated candidate vaccine by reverse genetics with the hemagglutinin and neuraminidase genes of the eq/GA/81 wild-type (wt) virus and the six internal protein genes of the cold-adapted (ca) A/Ann Arbor/6/60 (H2N2) vaccine donor virus, which is the backbone of the licensed seasonal live attenuated influenza vaccine. In both mice and ferrets, intranasal administration of a single dose of the eq/GA/81 ca vaccine virus induced neutralizing antibodies and conferred complete protection from homologous wt virus challenge in the upper respiratory tract. One dose of the eq/GA/81 ca vaccine also induced neutralizing antibodies and conferred complete protection in mice and nearly complete protection in ferrets upon heterologous challenge with the H3N8 (eq/Newmarket/03) wt virus. These data support further evaluation of the eq/GA/81 ca vaccine in humans for use in the event of transmission of an equine H3N8 influenza virus to humans. IMPORTANCE Equine influenza viruses have crossed the species barrier to infect other mammals such as dogs, pigs, and camels and therefore may also pose a threat to humans. We believe that it is important to develop vaccines against equine influenza viruses in the event that an EIV evolves, adapts, and spreads in humans, causing disease. We generated a live attenuated H3N8 vaccine candidate and demonstrated that the vaccine was immunogenic and

  6. Immune effects of the vaccine of live attenuated Aeromonas hydrophila screened by rifampicin on common carp (Cyprinus carpio L).

    PubMed

    Jiang, Xinyu; Zhang, Chao; Zhao, Yanjing; Kong, Xianghui; Pei, Chao; Li, Li; Nie, Guoxing; Li, Xuejun

    2016-06-08

    Aeromonas hydrophila, as a strong Gram-negative bacterium, can infect a wide range of freshwater fish, including common carp Cyprinus carpio, and cause the huge economic loss. To create the effective vaccine is the best way to control the outbreak of the disease caused by A. hydrophila. In this study, a live attenuated A. hydrophila strain, XX1LA, was screened from the pathogenic A. hydrophila strain XX1 cultured on medium containing the antibiotic rifampicin, which was used as a live attenuated vaccine candidate. The immune protection of XX1LA against the pathogen A. hydrophila in common carp was evaluated by the relative percent survival (RPS), the specific IgM antibody titers, serum lysozyme activity and the expression profiles of multiple immune-related genes at the different time points following immunization. The results showed that the variable up-regulations of the immune-related genes, such as the pro-inflammatory cytokine IL-1β, the chemokine IL-10 and IgM, were observed in spleen and liver of common carp injected in the vaccines with the formalin-killed A. hydrophila (FKA) and the live attenuated XX1LA. Specific antibody to A. hydrophila was found to gradually increase during 28 days post-vaccination (dpv), and the RPS (83.7%) in fish vaccinated with XX1LA, was significant higher than that (37.2%) in fish vaccinated with FKA (P<0.05) on Day 28 after challenged by pathogen. It was demonstrated that the remarkable immune protection presented in the group vaccinated with XX1LA. During the late stage of 4-week immunization phase, compared with FKA and the control, specific IgM antibody titers significantly increased (P<0.05) in the XX1LA group. The activity of the lysozyme in serum indicated no significant change among three groups. In summary, the live attenuated bacterial vaccine XX1LA, screened in this study, indicates the better protect effect on common carp against A. hydrophila, which can be applied in aquaculture of common carp to prevent from the

  7. Cell mediated immune response after challenge in Omp25 liposome immunized mice contributes to protection against virulent Brucella abortus 544.

    PubMed

    Goel, Divya; Rajendran, Vinoth; Ghosh, Prahlad C; Bhatnagar, Rakesh

    2013-02-06

    Brucellosis is a disease affecting various domestic and wild life species, and is caused by a bacterium Brucella. Keeping in view the serious economic and medical consequences of brucellosis, efforts have been made to prevent the infection through the use of vaccines. Cell-mediated immune responses [CMI] involving interferon gamma and cytotoxic CD4(+) and CD8(+) T cells are required for removal of intracellular Brucella. Omp25 has been reported to be involved in virulence of Brucella melitensis, Brucella abortus and Brucella ovis. In our previous study, we have shown the protective efficacy of recombinant Omp25, when administered intradermally. In this study, the recombinant Omp25 was formulated in PC-PE liposomes and PLGA microparticles, to enhance the protective immunity generated by it. Significant protection was seen with prime and booster liposome immunization in Balb/c mice against virulent B. abortus 544 as it was comparable to B. abortus S-19 vaccine strain. However, microparticle prime and booster immunization failed to give better protection when compared to B. abortus S-19 vaccine strain. This difference can be attributed to the stimulation of cell mediated immune response in PC-PE liposome immunized mice even after challenge which converted to cytotoxicity seen in CD4(+) and CD8(+) enriched lymphocytes. However, in PLGA microparticle immunized mice, cell mediated immunity was not generated after challenge as observed by decreased cytotoxicity of CD4(+) and CD8(+) enriched lymphocytes. Our study emphasizes on the importance of liposome encapsulating Omp25 immunization in conferring protection against B. abortus 544 challenge in Balb/c mice with a single dose immunization regimen.

  8. Public health impact and cost effectiveness of mass vaccination with live attenuated human rotavirus vaccine (RIX4414) in India: model based analysis

    PubMed Central

    Hawthorn, Rachael L; Watts, Brook; Singer, Mendel E

    2009-01-01

    Objectives To examine the public health impact of mass vaccination with live attenuated human rotavirus vaccine (RIX4414) in a birth cohort in India, and to estimate the cost effectiveness and affordability of such a programme. Design Decision analytical Markov model encompassing all direct medical costs. Infection risk and severity depended on age, number of previous infections, and vaccination history; probabilities of use of inpatient and outpatient health services depended on symptom severity. Data sources Published clinical, epidemiological, and economic data. When possible, parameter estimates were based on data specific for India. Population Simulated Indian birth cohort followed for five years. Main outcome measures Decrease in rotavirus gastroenteritis episodes (non-severe and severe), deaths, outpatient visits, and admission to hospital; incremental cost effectiveness ratio of vaccination expressed as net cost in 2007 rupees per life year saved. Results In the base case, vaccination prevented 28 943 (29.7%) symptomatic episodes, 6981 (38.2%) severe episodes, 164 deaths (41.0%), 7178 (33.3%) outpatient visits, and 812 (34.3%) admissions to hospital per 100 000 children. Vaccination cost 8023 rupees (about £100, €113, $165) per life year saved, less than India’s per capita gross domestic product, a common criterion for cost effectiveness. The net programme cost would be equivalent to 11.6% of the 2006-7 budget of the Indian Department of Health and Family Welfare. Model results were most sensitive to variations in access to outpatient care for those with severe symptoms. If this parameter was increased to its upper limit, the incremental cost effectiveness ratio for vaccination still fell between one and three times the per capita gross domestic product, meeting the World Health Organization’s criterion for “cost effective” interventions. Uncertainty analysis indicated a 94.7% probability that vaccination would be cost effective according to

  9. Chlamydophila abortus infection in the mouse: a useful model of the ovine disease.

    PubMed

    Caro, M R; Buendía, A J; Del Rio, L; Ortega, N; Gallego, M C; Cuello, F; Navarro, J A; Sanchez, J; Salinas, J

    2009-03-16

    Chlamydophila (C.) abortus is an obligate intracellular bacterium able to colonize the placenta of several species of mammals, which may induce abortion in the last third of pregnancy. The infection affects mainly small ruminants resulting in major economic losses in farming industries worldwide. Furthermore, its zoonotic risk has been reported in pregnant farmers or abattoir workers. Mouse models have been widely used to study both the pathology of the disease and the role of immune cells in controlling infection. Moreover, this animal experimental model has been considered a useful tool to evaluate new vaccine candidates and adjuvants that could prevent abortion and reduce fetal death. Future studies using these models will provide and reveal information about the precise mechanisms in the immune response against C. abortus and will increase the knowledge about poorly understood issues such as chlamydial persistence.

  10. Development of live attenuated Streptococcus agalactiae vaccine for tilapia via continuous passage in vitro.

    PubMed

    Li, L P; Wang, R; Liang, W W; Huang, T; Huang, Y; Luo, F G; Lei, A Y; Chen, M; Gan, X

    2015-08-01

    Fish Streptococcus agalactiae (S. agalactiae) seriously harms the world's aquaculture industry and causes huge economic losses. This study aimed to develop a potential live attenuated vaccine of S. agalactiae. Pre-screened vaccine candidate strain S. agalactiae HN016 was used as starting material to generate an attenuated strain S. agalactiae YM001 by continuous passage in vitro. The biological characteristics, virulence, and stability of YM001 were detected, and the protective efficacy of YM001 immunization in tilapia was also determined. Our results indicated that the growth, staining, characteristics of pulsed-field gel electrophoresis (PFGE) genotype, and virulence of YM001 were changed significantly as compared to the parental strain HN016. High doses of YM001 by intraperitoneal (IP) injection (1.0 × 10(9) CFU/fish) and oral gavage (1.0 × 10(10) CFU/fish) respectively did not cause any mortality and morbidity in tilapia. The relative percent survivals (RPSs) of fishes immunized with YM001 (1.0 × 10(8) CFU/fish, one time) via injection, immersion, and oral administration were 96.88, 67.22, and 71.81%, respectively, at 15 days, and 93.61, 60.56, and 53.16%, respectively, at 30 days. In all tests with 1-3 times of immunization in tilapia, the dosages at 1 × 10(8) and 1 × 10(9) CFU/fish displayed the similar best results, whereas the immunoprotection of the dosages at 1 × 10(6) and 1 × 10(7) CFU/fish declined significantly (P < 0.01), and 1 × 10(5) CFU/fish hardly displayed any protective effect. In addition, the efficacy of 2-3 times of immunization was significantly higher than that of single immunization (P < 0.01) while no significant difference in the efficacy between twice and thrice of immunization was seen (P > 0.05). The level of protective antibody elicited by oral immunization was significantly higher compared to that of the control group (P < 0.01), and the antibody reached their maximum levels 14-21 days after the immunization but decreased

  11. Cross-Protection against Marburg Virus Strains by Using a Live, Attenuated Recombinant Vaccine

    DTIC Science & Technology

    2006-10-01

    considered to have potential as a biological weapon. Recently, we reported the development of a promising attenuated, replication -competent vaccine against...MARV infections, we recently described the development of a promising new replication -competent vaccine against MARV based on recombinant vesicular...reported the development of a promising attenuated, replication -competent vaccine against MARV based on recombinant vesicular stomatitis virus (VSV

  12. Live Attenuated Recombinant Vaccine Protects Nonhuman Primates Against Ebola and Marburg Viruses

    DTIC Science & Technology

    2005-06-05

    Marburg virus (MARV). Here, we developed replication -competent vaccines against EBOV and MARV based on attenuated recombinant vesicular stomatitis...No evidence of EBOV or MARV replication was detected in any of the protected animals after challenge. Our data suggest that these vaccine...number of efforts have focused on developing vaccines against MARV. Alphavirus replicons expressing MARV proteins protected cynomolgus monkeys from

  13. Vaccine and serum-mediated protection against brucella infection of mouse placenta.

    PubMed Central

    Bosseray, N.

    1983-01-01

    Pregnant mice inoculated i.p. or i.v. with virulent Brucella abortus Strain 544 displayed strong infection, evidenced by brucella enumeration in placentas and dams' spleens. Vaccination 1 month before pregnancy decreased frequency of placental colonization and number of brucella per infected placenta and per spleen. Protein-bound cell wall peptidoglycan (PG) fractions extracted from brucella protected mice as well as H38 killed and B19 attenuated living vaccines. The lipopolysaccharide (LPS) fraction was comparatively less active. Immune serum injected i.v., either 24 h before or just after i.v. challenge of 15-day pregnant mice effectively transferred resistance to placental colonization. Anti LPS, anti PG and anti killed brucella sera protected mice as well as vaccination one month before pregnancy. The immunity transferred persisted for at least 3 days. PMID:6419766

  14. Enhanced expression of HIV and SIV vaccine antigens in the structural gene region of live attenuated rubella viral vectors and their incorporation into virions.

    PubMed

    Virnik, Konstantin; Ni, Yisheng; Berkower, Ira

    2013-04-19

    Despite the urgent need for an HIV vaccine, its development has been hindered by virus variability, weak immunogenicity of conserved epitopes, and limited durability of the immune response. For other viruses, difficulties with immunogenicity were overcome by developing live attenuated vaccine strains. However, there is no reliable method of attenuation for HIV, and an attenuated strain would risk reversion to wild type. We have developed rubella viral vectors, based on the live attenuated vaccine strain RA27/3, which are capable of expressing important HIV and SIV vaccine antigens. The rubella vaccine strain has demonstrated safety, immunogenicity, and long lasting protection in millions of children. Rubella vectors combine the growth and immunogenicity of live rubella vaccine with the antigenicity of HIV or SIV inserts. This is the first report showing that live attenuated rubella vectors can stably express HIV and SIV vaccine antigens at an insertion site located within the structural gene region. Unlike the Not I site described previously, the new site accommodates a broader range of vaccine antigens without interfering with essential viral functions. In addition, antigens expressed at the structural site were controlled by the strong subgenomic promoter, resulting in higher levels and longer duration of antigen expression. The inserts were expressed as part of the structural polyprotein, processed to free antigen, and incorporated into rubella virions. The rubella vaccine strain readily infects rhesus macaques, and these animals will be the model of choice for testing vector growth in vivo and immunogenicity.

  15. "Saving lives": Adapting and adopting Human Papilloma Virus (HPV) vaccination in Austria.

    PubMed

    Paul, Katharina T

    2016-03-01

    Vaccination against the sexually transmitted Human Papilloma Virus (HPV), a necessary agent for the development of cervical cancer, has triggered much debate. In Austria, HPV policy turned from "lagging behind" in 2008 into "Europe's frontrunner" by 2013. Drawing on qualitative research, the article shows how the vaccine was transformed and made "good enough" over the course of five years. By means of tinkering and shifting storylines, policy officials and experts disassociated the vaccine from gender, vaccine manufacturers, and youth sexuality. Ultimately, the HPV vaccine functioned to strengthen the national immunization program. To this end, preventing an effective problematization of the extant screening program was essential.

  16. Comparison of the immunogenicity and safety of measles vaccine administered alone or with live, attenuated Japanese encephalitis SA 14-14-2 vaccine in Philippine infants.

    PubMed

    Gatchalian, Salvacion; Yao, Yafu; Zhou, Benli; Zhang, Lei; Yoksan, Sutee; Kelly, Kim; Neuzil, Kathleen M; Yaïch, Mansour; Jacobson, Julie

    2008-04-24

    Japanese encephalitis (JE) virus is a major cause of disease, disability, and death in Asia. An effective, live, attenuated JE vaccine (LJEV) is available; however, its use in routine immunization schedules is hampered by lack of data on concomitant administration with measles vaccine (MV). This study evaluated the immunogenicity and reactogenicity of LJEV and MV when administered at the same or separate study visits in infants younger than 1 year of age. Three groups of healthy infants were randomized to receive LJEV at age of 8 months and MV at 9 months (Group 1; n=100); MV and LJEV together at 9 months (Group 2; n=236); or MV and LJEV at 9 and 10 months, respectively (Group 3; n=235). Blood was obtained 4 weeks after each vaccine administration to determine antibody levels for measles and JE. Reactogenicity was assessed by parental diaries and clinic visits. Four weeks after immunization, measles seroprotection rates (defined as > or =340 mIU/ml) were high and comparable in all three groups and specifically, rates in the combined MV-LJEV (Group 2) were not statistically inferior to those in Group 3 receiving MV separately (96% versus 100%, respectively). Likewise, the LJEV seroprotection rates were high and similar between the three groups. The reactogenicity profiles of the three vaccine schedules were also analogous. LJEV and MV administered together are well tolerated and immunogenic in infants younger than 1 year. These results should facilitate incorporation of LJEV into routine immunization schedules with MV.

  17. Canine Parvovirus (CPV) Vaccination: Comparison of Neutralizing Antibody Responses in Pups after Inoculation with CPV2 or CPV2b Modified Live Virus Vaccine

    PubMed Central

    Pratelli, Annamaria; Cavalli, Alessandra; Martella, Vito; Tempesta, Maria; Decaro, Nicola; Carmichael, Leland Eugene; Buonavoglia, Canio

    2001-01-01

    Canine parvovirus type 2 (CPV2) emerged in 1978 as causative agent of a new disease of dogs. New antigenic variants (biotypes), designated CPV2a and CPV2b, became widespread during 1979 to 1980 and 1984, respectively. At the present time the original CPV2 has disappeared in the dog population and has been replaced by the two new viruses. In the present study the comparison of neutralizing antibody titers in two groups of pups (18 pups in each group) inoculated with CPV2 and CPV2b modified live virus vaccines is reported. Using the hemagglutination inhibition (HI) test, relevant differences between antibody titers, against either the homologous or the heterologous virus, were not constantly observed. Using the neutralization (Nt) test, however, the pups inoculated with CPV2 had antibody titers which were approximately 30 times higher to the homologous virus (mean, 4,732) than to the heterologous virus (CPV2b) (mean, 162). The results of these experiments support two conclusions: (i) the HI test may not always accurately evaluate the true immune status of dogs with respect to CPV, and (ii) dogs inoculated with CPV2 vaccine develop relatively low Nt antibody titers against the heterologous virus (CPV2b). These data may suggest an advantage for new vaccines, considering that most presently licensed vaccines are produced with CPV2, which no longer exists in the dog population. PMID:11329467

  18. Comparison of the Live Attenuated Yellow Fever Vaccine 17D-204 Strain to Its Virulent Parental Strain Asibi by Deep Sequencing

    PubMed Central

    Beck, Andrew; Tesh, Robert B.; Wood, Thomas G.; Widen, Steven G.; Ryman, Kate D.; Barrett, Alan D. T.

    2014-01-01

    Background. The first comparison of a live RNA viral vaccine strain to its wild-type parental strain by deep sequencing is presented using as a model the yellow fever virus (YFV) live vaccine strain 17D-204 and its wild-type parental strain, Asibi. Methods. The YFV 17D-204 vaccine genome was compared to that of the parental strain Asibi by massively parallel methods. Variability was compared on multiple scales of the viral genomes. A modeled exploration of small-frequency variants was performed to reconstruct plausible regions of mutational plasticity. Results. Overt quasispecies diversity is a feature of the parental strain, whereas the live vaccine strain lacks diversity according to multiple independent measurements. A lack of attenuating mutations in the Asibi population relative to that of 17D-204 was observed, demonstrating that the vaccine strain was derived by discrete mutation of Asibi and not by selection of genomes in the wild-type population. Conclusions. Relative quasispecies structure is a plausible correlate of attenuation for live viral vaccines. Analyses such as these of attenuated viruses improve our understanding of the molecular basis of vaccine attenuation and provide critical information on the stability of live vaccines and the risk of reversion to virulence. PMID:24141982

  19. HPV awareness and vaccine acceptability in hispanic women living along the US-Mexico border.

    PubMed

    Molokwu, Jennifer; Fernandez, Norma P; Martin, Charmaine

    2014-06-01

    Despite advances in prevention of cervical cancer in the US, women of Hispanic origin still bear an unequal burden in cervical cancer incidence, morbidity and mortality. Our objective was to determine the HPV vaccine knowledge and acceptability in a group of mostly Hispanic females. In this cross sectional survey, 62 % of participants heard of HPV; 34.9 % identified HPV as a cause of cervical cancer. 63 % of participants reported willingness to receive vaccine and 77 % were willing to vaccinate daughters. Those with previous abnormal PAPs were more likely to have heard of HPV and Vaccine. No other factors examined showed association with willingness to get vaccine or administer to daughters. Knowledge level remains low in this high risk population. Willingness to receive vaccine is high despite lack of access to care. Increased targeted community based education and vaccination programs may be useful in closing disparity in cervical cancer morbidity.

  20. Efficacy of Fostera PRRS modified live virus vaccine against a Canadian heterologous virulent field strain of porcine reproductive and respiratory syndrome virus

    PubMed Central

    Savard, Christian; Alvarez, Fernando; Provost, Chantale; Chorfi, Younes; D’Allaire, Sylvie; Benoit-Biancamano, Marie-Odile; Gagnon, Carl A.

    2016-01-01

    Vaccination is a useful option to control infection with porcine reproductive and respiratory syndrome virus (PRRSV), and several modified live-PRRSV vaccines have been developed. These vaccines have shown some efficacy in reducing the incidence and severity of clinical disease as well as the duration of viremia and virus shedding but have failed to provide sterilizing immunity. The efficacy of modified live-virus (MLV) vaccines is greater against a homologous strain compared with heterologous PRRSV strains. The objective of this study was to evaluate the efficacy of Fostera PRRS MLV vaccine in protecting against challenge with a heterologous field strain widely circulating in the swine herds of eastern Canada. Forty-six piglets were divided into 4 groups: nonvaccinated-nonchallenged; nonvaccinated-challenged; vaccinated-challenged; and vaccinated-nonchallenged. The animals were vaccinated at 23 d of age with Fostera PRRS and challenged 23 d later with a heterologous field strain of PRRSV (FMV12-1425619). Overall, the vaccine showed some beneficial effects in the challenged animals by reducing the severity of clinical signs and the viral load. A significant difference between nonvaccinated and vaccinated animals was detected for some parameters starting 11 to 13 d after challenge, which suggested that the cell-mediated immune response or other delayed responses could be more important than pre-existing PRRSV antibodies in vaccinated animals within the context of protection against heterologous strains. PMID:26732457

  1. Comprehensive Identification of Immunodominant Proteins of Brucella abortus and Brucella melitensis Using Antibodies in the Sera from Naturally Infected Hosts.

    PubMed

    Wareth, Gamal; Eravci, Murat; Weise, Christoph; Roesler, Uwe; Melzer, Falk; Sprague, Lisa D; Neubauer, Heinrich; Murugaiyan, Jayaseelan

    2016-04-30

    Brucellosis is a debilitating zoonotic disease that affects humans and animals. The diagnosis of brucellosis is challenging, as accurate species level identification is not possible with any of the currently available serology-based diagnostic methods. The present study aimed at identifying Brucella (B.) species-specific proteins from the closely related species B. abortus and B. melitensis using sera collected from naturally infected host species. Unlike earlier reported investigations with either laboratory-grown species or vaccine strains, in the present study, field strains were utilized for analysis. The label-free quantitative proteomic analysis of the naturally isolated strains of these two closely related species revealed 402 differentially expressed proteins, among which 63 and 103 proteins were found exclusively in the whole cell extracts of B. abortus and B. melitensis field strains, respectively. The sera from four different naturally infected host species, i.e., cattle, buffalo, sheep, and goat were applied to identify the immune-binding protein spots present in the whole protein extracts from the isolated B. abortus and B. melitensis field strains and resolved on two-dimensional gel electrophoresis. Comprehensive analysis revealed that 25 proteins of B. abortus and 20 proteins of B. melitensis were distinctly immunoreactive. Dihydrodipicolinate synthase, glyceraldehyde-3-phosphate dehydrogenase and lactate/malate dehydrogenase from B. abortus, amino acid ABC transporter substrate-binding protein from B. melitensis and fumarylacetoacetate hydrolase from both species were reactive with the sera of all the tested naturally infected host species. The identified proteins could be used for the design of serological assays capable of detecting pan-Brucella, B. abortus- and B. melitensis-specific antibodies.

  2. Comprehensive Identification of Immunodominant Proteins of Brucella abortus and Brucella melitensis Using Antibodies in the Sera from Naturally Infected Hosts

    PubMed Central

    Wareth, Gamal; Eravci, Murat; Weise, Christoph; Roesler, Uwe; Melzer, Falk; Sprague, Lisa D.; Neubauer, Heinrich; Murugaiyan, Jayaseelan

    2016-01-01

    Brucellosis is a debilitating zoonotic disease that affects humans and animals. The diagnosis of brucellosis is challenging, as accurate species level identification is not possible with any of the currently available serology-based diagnostic methods. The present study aimed at identifying Brucella (B.) species-specific proteins from the closely related species B. abortus and B. melitensis using sera collected from naturally infected host species. Unlike earlier reported investigations with either laboratory-grown species or vaccine strains, in the present study, field strains were utilized for analysis. The label-free quantitative proteomic analysis of the naturally isolated strains of these two closely related species revealed 402 differentially expressed proteins, among which 63 and 103 proteins were found exclusively in the whole cell extracts of B. abortus and B. melitensis field strains, respectively. The sera from four different naturally infected host species, i.e., cattle, buffalo, sheep, and goat were applied to identify the immune-binding protein spots present in the whole protein extracts from the isolated B. abortus and B. melitensis field strains and resolved on two-dimensional gel electrophoresis. Comprehensive analysis revealed that 25 proteins of B. abortus and 20 proteins of B. melitensis were distinctly immunoreactive. Dihydrodipicolinate synthase, glyceraldehyde-3-phosphate dehydrogenase and lactate/malate dehydrogenase from B. abortus, amino acid ABC transporter substrate-binding protein from B. melitensis and fumarylacetoacetate hydrolase from both species were reactive with the sera of all the tested naturally infected host species. The identified proteins could be used for the design of serological assays capable of detecting pan-Brucella, B. abortus- and B. melitensis-specific antibodies. PMID:27144565

  3. Temperature-sensitive mutations for live-attenuated Rift Valley fever vaccines: implications from other RNA viruses

    PubMed Central

    Nishiyama, Shoko; Ikegami, Tetsuro

    2015-01-01

    Rift Valley fever (RVF) is a mosquito-borne zoonotic disease endemic to the African continent. RVF is characterized by high rate of abortions in ruminants and hemorrhagic fever, encephalitis, or blindness in humans. RVF is caused by the Rift Valley fever virus (RVFV: genus Phlebovirus, family Bunyaviridae). Vaccination is the only known effective strategy to prevent the disease, but there are no licensed RVF vaccines available for humans. A live-attenuated vaccine candidate derived from the wild-type pathogenic Egyptian ZH548 strain, MP-12, has been conditionally licensed for veterinary use in the U.S. MP-12 displays a temperature-sensitive (ts) phenotype and does not replicate at 41°C. The ts mutation limits viral replication at a specific body temperature and may lead to an attenuation of the virus. Here we will review well-characterized ts mutations for RNA viruses, and further discuss the potential in designing novel live-attenuated vaccines for RVF. PMID:26322023

  4. Temperature-sensitive mutations for live-attenuated Rift Valley fever vaccines: implications from other RNA viruses.

    PubMed

    Nishiyama, Shoko; Ikegami, Tetsuro

    2015-01-01

    Rift Valley fever (RVF) is a mosquito-borne zoonotic disease endemic to the African continent. RVF is characterized by high rate of abortions in ruminants and hemorrhagic fever, encephalitis, or blindness in humans. RVF is caused by the Rift Valley fever virus (RVFV: genus Phlebovirus, family Bunyaviridae). Vaccination is the only known effective strategy to prevent the disease, but there are no licensed RVF vaccines available for humans. A live-attenuated vaccine candidate derived from the wild-type pathogenic Egyptian ZH548 strain, MP-12, has been conditionally licensed for veterinary use in the U.S. MP-12 displays a temperature-sensitive (ts) phenotype and does not replicate at 41°C. The ts mutation limits viral replication at a specific body temperature and may lead to an attenuation of the virus. Here we will review well-characterized ts mutations for RNA viruses, and further discuss the potential in designing novel live-attenuated vaccines for RVF.

  5. A novel multiplex poliovirus binding inhibition assay applicable for large serosurveillance and vaccine studies, without the use of live poliovirus.

    PubMed

    Schepp, Rutger M; Berbers, Guy A M; Ferreira, José A; Reimerink, Johan H; van der Klis, Fiona R

    2017-03-01

    Large-scale serosurveillance or vaccine studies for poliovirus using the "gold standard" WHO neutralisation test (NT) are very laborious and time consuming. With the polio eradication at hand and with the removal of live attenuated Sabin strains from the oral poliovirus vaccine (OPV), starting with type 2 (as of April 2016), laboratories will need to conform to much more stringent laboratory biosafety regulations when handling live poliovirus strains. In this study, a poliovirus binding inhibition multiplex immunoassay (polio MIA) using inactivated poliovirus vaccine (IPV-Salk) was developed for simultaneous quantification of serum antibodies directed to all three poliovirus types. Our assay shows a good correlation with the NT and an excellent correlation with the ELISA-based binding inhibition assay (POBI). The assay is highly type-specific and reproducible. Additionally, serum sample throughput increases about fivefold relative to NT and POBI and the amount of serum needed is reduced by more than 90%. In conclusion, the polio MIA can be used as a safe and high throughput application, especially for large-scale surveillance and vaccine studies, reducing laboratory time and serum amounts needed.

  6. Generation of growth arrested Leishmania amastigotes: a tool to develop live attenuated vaccine candidates against visceral leishmaniasis.

    PubMed

    Selvapandiyan, Angamuthu; Dey, Ranadhir; Gannavaram, Sreenivas; Solanki, Sumit; Salotra, Poonam; Nakhasi, Hira L

    2014-06-30

    Visceral leishmaniasis (VL) is fatal if not treated and is prevalent widely in the tropical and sub-tropical regions of world. VL is caused by the protozoan parasite Leishmania donovani or Leishmania infantum. Although several second generation vaccines have been licensed to protect dogs against VL, there are no effective vaccines against human VL [1]. Since people cured of leishmaniasis develop lifelong protection, development of live attenuated Leishmania parasites as vaccines, which can have controlled infection, may be a close surrogate to leishmanization. This can be achieved by deletion of genes involved in the regulation of growth and/or virulence of the parasite. Such mutant parasites generally do not revert to virulence in animal models even under conditions of induced immune suppression due to complete deletion of the essential gene(s). In the Leishmania life cycle, the intracellular amastigote form is the virulent form and causes disease in the mammalian hosts. We developed centrin gene deleted L. donovani parasites that displayed attenuated growth only in the amastigote stage and were found safe and efficacious against virulent challenge in the experimental animal models. Thus, targeting genes differentially expressed in the amastigote stage would potentially attenuate only the amastigote stage and hence controlled infectivity may be effective in developing immunity. This review lays out the strategies for attenuation of the growth of the amastigote form of Leishmania for use as live vaccine against leishmaniasis, with a focus on visceral leishmaniasis.

  7. Avian metapneumovirus M2:2 protein inhibits replication in Vero cells: modification facilitates live vaccine development.

    PubMed

    Clubbe, Jayne; Naylor, Clive J

    2011-11-28

    Throughout the world, avian metapneumovirus (AMPV) infection of subtype A is principally controlled by two live vaccines both derived from UK field strain #8544. Improvements of those vaccines by use of reverse genetics technology was found to be hampered by the inability of #8544 to replicate in the commonly exploited Vero cell based reverse genetics system. A systematic reverse genetics based genome modification of a DNA copy of #8544, employing sequence data from a Vero grown, #8544 derived, live vaccine; was used to determine mutations required to facilitate virus recovery and replication in Vero cells. This identified a single coding substitution in the M2:2 reading frame as responsible. Furthermore, ablation of M2:2 was found to elicit the same outcome. M2:2 sequence analysis of seven AMPVs found Vero cell adaption to be associated with non similar amino acid changes in M2:2. The study shows that M2:2 modification of field virus #8544 will enable research leading to improved vaccines. This may have more general application to other AMPV field strains.

  8. Protein profiling in the gut of Penaeus monodon gavaged with oral WSSV-vaccines and live white spot syndrome virus.

    PubMed

    Kulkarni, Amod D; Kiron, Viswanath; Rombout, Jan H W M; Brinchmann, Monica F; Fernandes, Jorge M O; Sudheer, Naduvilamuriparampu S; Singh, Bright I S

    2014-07-01

    White spot syndrome virus (WSSV) is a pathogen that causes considerable mortality of the farmed shrimp, Penaeus monodon. Candidate 'vaccines', WSSV envelope protein VP28 and formalin-inactivated WSSV, can provide short-lived protection against the virus. In this study, P. monodon was orally intubated with the aforementioned vaccine candidates, and protein expression in the gut of immunised shrimps was profiled. The alterations in protein profiles in shrimps infected orally with live-WSSV were also examined. Seventeen of the identified proteins in the vaccine and WSSV-intubated shrimps varied significantly compared to those in the control shrimps. These proteins, classified under exoskeletal, cytoskeletal, immune-related, intracellular organelle part, intracellular calcium-binding or energy metabolism, are thought to directly or indirectly affect shrimp's immunity. The changes in the expression levels of crustacyanin, serine proteases, myosin light chain, and ER protein 57 observed in orally vaccinated shrimp may probably be linked to immunoprotective responses. On the other hand, altered expression of proteins linked to exoskeleton, calcium regulation and energy metabolism in WSSV-intubated shrimps is likely to symbolise disturbances in calcium homeostasis and energy metabolism.

  9. Experience with live attenuated varicella vaccine (Oka strain) in healthy Japanese subjects; 10-year survey at pediatric clinic.

    PubMed

    Ozaki, T; Nishimura, N; Kajita, Y

    2000-05-08

    Live attenuated varicella vaccine (Oka strain, Biken Institute, Osaka, Japan) was administered to 973 healthy individuals over a 10-year period (1987-1997) at the pediatric clinic of Showa Hospital in Japan. We evaluated the relevant serological and clinical data, which were collected by questionnaire. Seroconversion by the immune adherence hemagglutination method was documented in 94% (805/860) of the initially seronegative subjects. Of the initially seropositive subjects, 56% (63/113) showed enhancement of antibody after vaccination. Reactions to the vaccine were generally insignificant, except for a rash at the injection site, seen in the first 3 days post-administration in 17% (41/241) of the recently vaccinated subjects. In March 1998, we conducted a survey of 559 of the initially seronegative subjects who had received the vaccine 0.6-10. 8 (mean 5.4) years earlier. Of these subjects, 21% (119/559) contracted breakthrough varicella. However, their symptoms were milder than those caused by natural varicella seen in unvaccinated children. Seroconversion was demonstrated in 92% (109/119) of these cases. The incidence of breakthrough disease decreased with a rise in postvaccination antibody titer to >==32. Four of the subjects (0.7% of 559) developed herpes zoster following vaccination, two of whom had earlier exhibited breakthrough varicella. Lesions in one case of zoster, without breakthrough varicella, appeared on the cervical dermatome at the injection site. The vaccine was safe and effective. However, there was a relatively high incidence of rash at the injection site with certain lot numbers used in recent years which warrants investigation.

  10. Comparative efficacy of various chemical stabilizers on the thermostability of a live-attenuated peste des petits ruminants (PPR) vaccine.

    PubMed

    Sarkar, J; Sreenivasa, B P; Singh, R P; Dhar, P; Bandyopadhyay, S K

    2003-12-01

    Thermostability of a live-attenuated peste des petits ruminants (PPR) vaccine recently developed at Indian Veterinary Research Institute was studied using conventional lyophilization conditions. A total of four stabilizers viz., lactalbumin hydrolysate-sucrose (LS), Weybridge medium (WBM), buffered gelatin-sorbitol (BUGS) and trehalose dihydrate (TD) were used to prepare the lyophilized vaccine. The study revealed that the PPR vaccine lyophilized with either LS or TD is more stable than rest of the stabilizers having an expiry period of at least 45 days (so far studied) at 4 degrees C, 15-19 days at 25 degrees C and 1-2 days at 37 degrees C. However, at a temperature of 45 degrees C, BUGS had a marginal superiority, although lasted for few hours, followed by TD and LS with respect to shelf-life, LS and TD with respect to half-life. On the basis of half-life also LS followed by TD appeared superior at a temperature of 4, 25 and 37 degrees C. Reconstitution of vaccine with distilled water or 1M MgSO(4) or 0.85% NaCl maintained the required virus titre (2.5log(10)TCID(50) per dose) up to 8h at 37 degrees C and 7h at 45 degrees C. Among the three diluents, 1M MgSO(4) appeared to be the better diluent for reconstitution of lyophilized PPR vaccine, as the loss on dilution was lowest and maintain the required virus titre for a longer period. Investigation suggests for using LS as stabilizer for lyophilization and 1M MgSO(4) as vaccine diluent for the newly developed PPR vaccine.

  11. Public health impact and cost-effectiveness of intranasal live attenuated influenza vaccination of children in Germany.

    PubMed

    Damm, Oliver; Eichner, Martin; Rose, Markus Andreas; Knuf, Markus; Wutzler, Peter; Liese, Johannes Günter; Krüger, Hagen; Greiner, Wolfgang

    2015-06-01

    In 2011, intranasally administered live attenuated influenza vaccine (LAIV) was approved in the EU for prophylaxis of seasonal influenza in 2-17-year-old children. Our objective was to estimate the potential epidemiological impact and cost-effectiveness of an LAIV-based extension of the influenza vaccination programme to healthy children in Germany. An age-structured dynamic model of influenza transmission was developed and combined with a decision-tree to evaluate different vaccination strategies in the German health care system. Model inputs were based on published literature or were derived by expert consulting using the Delphi technique. Unit costs were drawn from German sources. Under base-case assumptions, annual routine vaccination of children aged 2-17 years with LAIV assuming an uptake of 50% would prevent, across all ages, 16 million cases of symptomatic influenza, over 600,000 cases of acute otitis media, nearly 130,000 cases of community-acquired pneumonia, nearly 1.7 million prescriptions of antibiotics and over 165,000 hospitalisations over 10 years. The discounted incremental cost-effectiveness ratio was 1,228 per quality-adjusted life year gained from a broad third-party payer perspective (including reimbursed direct costs and specific transfer payments), when compared with the current strategy of vaccinating primarily risk groups with the conventional trivalent inactivated vaccine. Inclusion of patient co-payments and indirect costs in terms of productivity losses resulted in discounted 10-year cost savings of 3.4 billion. In conclusion, adopting universal influenza immunisation of healthy children and adolescents would lead to a substantial reduction in influenza-associated disease at a reasonable cost to the German statutory health insurance system. On the basis of the epidemiological and health economic simulation results, a recommendation of introducing annual routine influenza vaccination of children 2-17 years of age might be

  12. Safety of Japanese encephalitis live attenuated vaccination in post-marketing surveillance in Guangdong, China, 2005-2012.

    PubMed

    Liu, Yu; Lin, Hualiang; Zhu, Qi; Wu, Chenggang; Zhao, Zhanjie; Zheng, Huizhen

    2014-03-26

    We reviewed the adverse events following immunization of live attenuated Japanese encephalitis vaccine in Guangdong Province, China. During the period of 2005-2012, 23 million doses of live attenuated Japanese encephalitis vaccine were used and 1426 adverse events were reported (61.24 per million doses); of which, 570 (40%) were classified as allergic reactions (24.48 per million doses), 31 (2%) were neurologic events (1.33 per million doses), and 36 (2.5%) were diagnosed as serious adverse events (1.55 per million doses). This study suggests that the JEV-L has a reasonable safety profile, most adverse events are relatively mild, with relatively rare neurologic events being observed.

  13. Comparison of live Eimeria vaccination with in-feed salinomycin on growth and immune status in broiler chickens.

    PubMed

    Lee, Kyung-Woo; Lillehoj, Hyun-Soon; Jang, Seung-Ik; Lee, Sung-Hyen; Bautista, Daniel A; Donald Ritter, G; Lillehoj, Erik P; Siragusa, Gregory R

    2013-08-01

    Coccidiosis vaccines and anticoccidial drugs are commonly used to control Eimeria infection during commercial poultry production. The present study was conducted to compare the relative effectiveness of these two disease control strategies in broiler chickens in an experimental research facility. Birds were orally vaccinated with a live, attenuated vaccine (Inovocox), or were provided with in-feed salinomycin (Bio-Cox), and body weights, serum levels of nitric oxide (NO) and antibodies against Eimeria profilin and Clostridium perfringens PFO proteins, and intestinal levels of cytokine gene transcripts were measured. Vaccinated chickens had increased body weights, greater NO levels, and higher profilin and PFO antibody levels compared with salinomycin-fed birds. Transcripts for interleukin-6 (IL-6), tumor necrosis factor superfamily 15, and interferon-γ were increased, while mRNAs for IL-4 and IL-10 were decreased, in immunized chickens compared with salinomycin-treated chickens. In conclusion, vaccination against avian coccidiosis may be more effective compared with dietary salinomycin for increasing body weight and augmenting pro-inflammatory immune status during commercial poultry production.

  14. Protection of dogs for 13 months against Bordetella bronchiseptica and canine parainfluenza virus with a modified live vaccine.

    PubMed

    Jacobs, A A C; Theelen, R P H; Jaspers, R; Horspool, L J I; Sutton, D; Bergman, J G H E; Paul, G

    2005-07-02

    Twelve specific pathogen-free (spf) puppies were vaccinated intranasally with a bivalent, modified live vaccine against infectious tracheobronchitis (group 1) and six puppies of the same age and from the same source served as unvaccinated controls (group 2). Both groups were challenged with wild-type Bordetella bronchiseptica and canine parainfluenza virus by the aerosol route 56 weeks after group 1 had been vaccinated, and at the same time six 10-week-old spf puppies from the same source (group 3) were also challenged. Oronasal swabs were taken regularly before and after the challenge, for the isolation of bacteria and viruses, and the dogs were observed for clinical signs for three weeks after the challenge. The control dogs became culture-positive for B bronchiseptica and canine parainfluenza virus, but the isolation yields from the vaccinated group were significantly lower (P<0.05). The mean clinical scores of the vaccinated group were 61 per cent lower than the scores of group 2 (P=0.009), and 90 per cent lower than the scores of group 3 (P=0.001).

  15. Protection Induced in Broiler Chickens following Drinking-Water Delivery of Live Infectious Laryngotracheitis Vaccines against Subsequent Challenge with Recombinant Field Virus.

    PubMed

    Korsa, Mesula G; Browning, Glenn F; Coppo, Mauricio J C; Legione, Alistair R; Gilkerson, James R; Noormohammadi, Amir H; Vaz, Paola K; Lee, Sang-Won; Devlin, Joanne M; Hartley, Carol A

    2015-01-01

    Infectious laryngotracheitis virus (ILTV) causes acute upper respiratory tract disease in chickens. Attenuated live ILTV vaccines are often used to help control disease, but these vaccines have well documented limitations, including retention of residual virulence, incomplete protection, transmission of vaccine virus to unvaccinated birds and reversion to high levels of virulence following bird-to-bird passage. Recently, two novel ILTV field strains (class 8 and 9 ILTV viruses) emerged in Australia due to natural recombination between two genotypically distinct commercial ILTV vaccines. These recombinant field strains became dominant field strains in important poultry producing areas. In Victoria, Australia, the recombinant class 9 virus largely displaced the previously predominant class 2 ILTV strain. The ability of ILTV vaccines to protect against challenge with the novel class 9 ILTV strain has not been studied. Here, the protection induced by direct (drinking-water) and indirect (contact) exposure to four different ILTV vaccines against challenge with class 9 ILTV in commercial broilers was studied. The vaccines significantly reduced, but did not prevent, challenge virus replication in vaccinated chickens. Only one vaccine significantly reduced the severity of tracheal pathology after direct drinking-water vaccination. The results indicate that the current vaccines can be used to help control class 9 ILTV, but also indicate that these vaccines have limitations that should be considered when designing and implementing disease control programs.

  16. The persistence of component Theileria parva stocks in cattle immunized with the 'Muguga cocktail' live vaccine against East Coast fever in Uganda.

    PubMed

    Oura, C A L; Bishop, R; Wampande, E M; Lubega, G W; Tait, A

    2004-07-01

    The 'Muguga cocktail' live vaccine comprises three Theileria parva stocks (Muguga, Kiambu 5 and the buffalo-derived Serengeti-transformed) and has been used extensively in Eastern, Central and Southern Africa with an infection and treatment protocol to protect cattle against East Coast fever. We report the characterization of the three component vaccine stocks using a panel of polymorphic micro-satellite and mini-satellite markers and the development of a stock-derived PCR method that distinguishes two of the vaccine stocks. These markers, with the use of a recently developed Reverse Line Blot assay, have enabled us to address four important questions in relation to vaccination. First, how closely related are the vaccine stocks, secondly do all three stocks persist post-vaccination and induce a carrier state, thirdly is there evidence for the transmission of the vaccine stocks and fourthly does vaccination prevent infection with local genotypes? The results show that Muguga and Serengeti-transformed stocks are highly related but very distinct from Kiambu 5 that persists in vaccinated cattle establishing a carrier state. No evidence was obtained for the transmission of vaccine stocks to co-grazed animals, although these animals were infected with up to 8 different T. parva genotypes showing there was a significant level of tick challenge. Some of the vaccinated animals become infected with a subset of local genotypes providing evidence for limited vaccine 'breakthrough'.

  17. Development and characterization of an infectious cDNA clone of the modified live virus vaccine strain of equine arteritis virus.

    PubMed

    Zhang, Jianqiang; Go, Yun Young; Huang, Chengjin M; Meade, Barry J; Lu, Zhengchun; Snijder, Eric J; Timoney, Peter J; Balasuriya, Udeni B R

    2012-08-01

    A stable full-length cDNA clone of the modified live virus (MLV) vaccine strain of equine arteritis virus (EAV) was developed. RNA transcripts generated from this plasmid (pEAVrMLV) were infectious upon transfection into mammalian cells, and the resultant recombinant virus (rMLV) had 100% nucleotide identity to the parental MLV vaccine strain of EAV. A single silent nucleotide substitution was introduced into the nucleocapsid gene (pEAVrMLVB), enabling the cloned vaccine virus (rMLVB) to be distinguished from parental MLV vaccine as well as other field and laboratory strains of EAV by using an allelic discrimination real-time reverse transcription (RT)-PCR assay. In vitro studies revealed that the cloned vaccine virus rMLVB and the parental MLV vaccine virus had identical growth kinetics and plaque morphologies in equine endothelial cells. In vivo studies confirmed that the cloned vaccine virus was very safe and induced high titers of neutralizing antibodies against EAV in experimentally immunized horses. When challenged with the heterologous EAV KY84 strain, the rMLVB vaccine virus protected immunized horses in regard to reducing the magnitude and duration of viremia and virus shedding but did not suppress the development of signs of EVA, although these were reduced in clinical severity. The vaccine clone pEAVrMLVB could be further manipulated to improve the vaccine efficacy as well as to develop a marker vaccine for serological differentiation of EAV naturally infected from vaccinated animals.

  18. Clinical trials with Alice strain, live, attenuated, serum inhibitor-resistant intranasal influenza A vaccine.

    PubMed

    Spencer, M J; Cherry, J D; Powell, K R; Sumaya, C V; Garakian, A J

    1975-10-01

    Two clinical trials with Alice strain intranasal influenza vaccine were performed. In study no. 1 (utilizing random selection and double-blind control), 50 subjects received a bivalent inactivated influenza vaccine intramuscularly, 99 subjects received Alice strain vaccine intranasally, and 50 subjects received a placebo intranasally. No symptomatology could be attributed to the intranasal route of immunization. Convalescent-phase geometric mean titers of hemagglutination inhibition antibody were higher after intramuscular vaccination; seroconversion occurred in 16 or 17 recipients of the Alice strain, with initial titers of less than 1:8. Clinical and virologic surveillance for 20 weeks after vaccination revealed no influenza A illnesses in participants of the study. In study no. 2, 75% of the subjects with initial nasal antibody titers of less than 1:3 developed measurable nasal antibody after receiving Alice strain vaccine.

  19. Identification of in vitro upregulated genes in a modified live vaccine strain of Edwardsiella ictaluri compared to a virulent parent strain

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Using PCR-select subtractive cDNA hybridization technique, 41 expressed sequence tags (ESTs) were isolated from a modified live vaccine strain (AQUAVAC-ESC©, formerly RE-33) vs a virulent parent strain (EILO) of Edwardsiella ictaluri. Transcriptional levels of the 41 ESTs in the vaccine strain and t...

  20. A live attenuated Salmonella enterica serovar Typhimurium vaccine provides cross-protection against Salmonella serovars to reduce disease severity and pathogen transmission

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A live attenuated Salmonella enterica serovar Typhimurium vaccine was developed to confer broad protection against multiple Salmonella serovars to prevent disease and reduce pathogen colonization and shedding. Two vaccine trials were performed in swine to determine the protection afforded by the vac...

  1. An alphavirus vector-based tetravalent dengue vaccine induces a rapid and protective immune response in macaques that differs qualitatively from immunity induced by live virus infection.

    PubMed

    White, Laura J; Sariol, Carlos A; Mattocks, Melissa D; Wahala M P B, Wahala; Yingsiwaphat, Vorraphun; Collier, Martha L; Whitley, Jill; Mikkelsen, Rochelle; Rodriguez, Idia V; Martinez, Melween I; de Silva, Aravinda; Johnston, Robert E

    2013-03-01

    Despite many years of research, a dengue vaccine is not available, and the more advanced live attenuated vaccine candidate in clinical trials requires multiple immunizations with long interdose periods and provides low protective efficacy. Here, we report important contributions to the development of a second-generation dengue vaccine. First, we demonstrate that a nonpropagating vaccine vector based on Venezuelan equine encephalitis virus replicon particles (VRP) expressing two configurations of dengue virus E antigen (subviral particles [prME] and soluble E dimers [E85]) successfully immunized and protected macaques against dengue virus, while antivector antibodies did not interfere with a booster immunization. Second, compared to prME-VRP, E85-VRP induced neutralizing antibodies faster, to higher titers, and with improved protective efficacy. Third, this study is the first to map antigenic domains and specificities targeted by vaccination versus natural infection, revealing that, unlike prME-VRP and live virus, E85-VRP induced only serotype-specific antibodies, which predominantly targeted EDIII, suggesting a protective mechanism different from that induced by live virus and possibly live attenuated vaccines. Fourth, a tetravalent E85-VRP dengue vaccine induced a simultaneous and protective response to all 4 serotypes after 2 doses given 6 weeks apart. Balanced responses and protection in macaques provided further support for exploring the immunogenicity and safety of this vaccine candidate in humans.

  2. Heightened adaptive immune responses following vaccination with a temperature-sensitive, live-attenuated influenza virus compared to adjuvanted, whole-inactivated virus in pigs

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In the United States there are currently two influenza vaccine platforms approved for use in humans - conventional inactivated virus and live-attenuated influenza virus (LAIV). One of the major challenges for influenza A virus (IAV) vaccination is designing a platform that provides protection across...

  3. Comparison of the immune responses in BALB/c mice following immunization with DNA-based and live attenuated vaccines delivered via different routes.

    PubMed

    Cai, Ming-sheng; Deng, Shu-xuan; Li, Mei-li

    2013-02-18

    The objective of this study was to compare immune responses induced in BALB/c mice following immunization with pcDNA-GPV-VP2 DNA by gene gun bombardment (6 μg) or by intramuscular (im) injection (100 μg) with the responses to live attenuated vaccine by im injection (100 μl). pcDNA3.1 (+) and physiological saline were used as controls. Peripheral blood samples were collected at 3, 7, 14, 21, 28, 35, 49, 63, 77 and 105 d after immunization. T lymphocyte proliferation was analyzed by MTT assay and enumeration of CD4(+), and CD8(+) T cell populations in peripheral blood was performed by flow cytometric analysis. Indirect ELISA was used to detect IgG levels. Cellular and humoral responses were induced by pcDNA-GPV-VP2 DNA and live virus vaccines. No differences were observed in T cell proliferation and CD8(+) T cell responses induced by the genetic vaccine regardless of the route of delivery. However, CD4(+) T cell responses and humoral immunity were enhanced in following gene gun immunization compared with im injection of the genetic vaccine. Cellular and humoral immunity was enhanced in following gene gun delivery of the genetic vaccine compared with the live attenuated vaccine. In conclusion, the pcDNA-GPV-VP2 DNA vaccine induced enhanced cellular and humoral immunity compared with that induced by the live attenuated vaccine.

  4. Control of Salmonella Enteritidis and Salmonella Gallinarum in birds by using live vaccine candidate containing attenuated Salmonella Gallinarum mutant strain.

    PubMed

    Penha Filho, Rafael Antonio Casarin; de Paiva, Jacqueline Boldrin; da Silva, Mariana Dias; de Almeida, Adriana Maria; Berchieri, Angelo

    2010-04-01

    The ideal live vaccine to control Salmonella in commercial chicken flocks should engender protection against various strains. The purpose of the present study was to confirm the attenuation of a Salmonella Gallinarum (SG) mutant strain with deletion on genes cobS and cbiA, that are involved in the biosynthesis of cobalamin. Furthermore, evaluate its use as a live vaccine against Salmonella. For the evaluation of the vaccine efficacy, two experiments were conducted separately. Birds from a commercial brown line of chickens were used to perform challenge with SG wild type strain and birds from a commercial white line of chickens were used to perform challenge with Salmonella Enteritidis (SE) wild type strain. In both experiments, the birds were separated in three groups (A, B and C). Birds were orally vaccinated with the SG mutant as the following programme: group A, one dose at 5 days of age; group B, one dose at 5 days of age and a second dose at 25 days of age; and group C, birds were kept unvaccinated as controls. At 45 days of age, birds from all groups, including the control, were challenged orally by SG wild type (brown line) or SE wild type (white line). Lastly, another experiment was performed to evaluate the use of the SG mutant strain to prevent caecal colonization by SE wild type on 1-day-old broiler chicks. Mortality and systemic infection by SG wild type strain were assessed in brown chickens; faecal shedding and systemic infection by SE wild type were assessed in white chickens and caecal colonization was assessed in broiler chicks. Either vaccination with one or two doses of SG mutant, were capable to protect brown chickens against SG wild type. In the experiment with white chickens, only vaccination with two doses of SG mutant protected the birds against challenge with SE wild type. Although, SG mutant could not prevent caecal colonization in 1-day-old broiler chicks by the challenge strain SE wild type. Overall, the results indicated that SG mutant

  5. Experimental study of a further attenuated live measles vaccine of the Sugiyama strain in Iran

    PubMed Central

    Mirchamsy, H.; Shafyi, A.; Rafyi, M. R.; Bahrami, S.; Nazari, P.; Fatemie, S.

    1974-01-01

    After encouraging results of the mass vaccination programme in Iran, in which 5 million children in rural areas were vaccinated with the Japanese Sugiyama strain at its 82nd passage in baby calf kidney, and a progressive decrease in the incidence of measles as well as a reduction of excessive infant mortality, a further attenuated vaccine, produced with the same strain, cloned in Japan, was compared in a field trial with the parent vaccine. The new strain caused fewer reactions than the original strain. Seroconversion with a geometric mean antibody titre of 6·1 was observed in 95% of susceptible children. PMID:4522721

  6. A Live Attenuated H7N3 Influenza Virus Vaccine is Well-tolerated and Immunogenic in a Phase I Trial in Healthy Adults

    PubMed Central

    Talaat, Kawsar R.; Karron, Ruth A.; Callahan, Karen A.; Luke, Catherine J.; DiLorenzo, Susan C.; Chen, Grace L.; Lamirande, Elaine W.; Jin, Hong; Coelingh, Kathy L.; Murphy, Brian R.; Kemble, George; Subbarao, Kanta

    2009-01-01

    Background Live attenuated influenza vaccines (LAIV) are being developed and tested against a variety of influenza viruses with pandemic potential. We describe the results of an open label Phase I trial of a live attenuated H7N3 virus vaccine. Methods and Findings The H7N3 BC 2004/AA ca virus is a live attenuated, cold-adapted, temperature-sensitive influenza virus derived by reverse genetics from the wild-type low pathogenicity avian influenza virus A/chicken/British Columbia/CN-6/2004 (H7N3) and the A/AA/6/60 ca (H2N2) virus that is the Master Donor Virus of the live, intranasal seasonal influenza vaccine. We evaluated the safety, infectivity, and immunogenicity of two doses of 107.5 TCID50 of the vaccine administered by nasal spray 5 weeks apart to normal healthy seronegative adult volunteers in an inpatient isolation unit. The subjects were followed for 2 months after 1 dose of vaccine or for 4 weeks after the second dose. Twenty-one subjects received the first dose of the vaccine, and 17 subjects received two doses. The vaccine was generally well tolerated. No serious adverse events occurred during the trial. The vaccine was highly restricted in replication: 6 (29%) subjects had virus recoverable by culture or by rRT-PCR after the first dose. Replication of vaccine virus was not detected following the second dose. Despite the restricted replication of the vaccine, 90% of the subjects developed an antibody response as measured by any assay: 62% by hemagglutination inhibition assay, 48% by microneutralization assay, 48% by ELISA for H7 HA-specific serum IgG or 71% by ELISA for H7 HA-specific serum IgA, after either one or two doses. Following the first dose, vaccine-specific IgG secreting cells as measured by ELISPOT increased from a mean of 0.1 to 41.6/106 PBMCs; vaccine specific IgA secreting cells increased from 2 to 16.4/106 PBMCs. The antibody secreting cell response after the second dose was less vigorous, which is consistent with the observed low

  7. Comparison of the efficacy of Poly(I:C) immunization with live vaccine and formalin-killed vaccine against viral hemorrhagic septicemia virus (VHSV) in olive flounder (Paralichthys olivaceus).

    PubMed

    Kim, Hyoung Jun; Park, Jeong Su; Choi, Min Chul; Kwon, Se Ryun

    2016-01-01

    Viral hemorrhagic septicemia (VHS) in olive flounder, Paralichthys olivaceus, causes significant economic loss for the flounder aquaculture industry in Korea. In this study, the immunogenicity of Poly(I:C) immunization with a live vaccine against the VHS virus (VHSV) was compared with that of a formalin-treated vaccine in the olive flounder. In vaccine trial I, fish pre-injected with Poly(I:C) were highly protected from VHSV infection 2 d later (survival rate: 96%) and the surviving fish (Poly(I:C)-VHSV group) showed a 100% survival rate against VHSV re-challenge. Mortality in fish pre-injected with diethylpyrocarbonate-treated water followed by injection with formalin-treated VHSV was only 2% (1 of 50 fish), whereas survivors (DEPC-FT VHSV group) showed an 80% survival rate. In vaccine trial II, 100% survival was observed in all Poly(I:C) vaccination groups-Poly(I:C)-VHSV 6, Poly(I:C)-VHSV 5, and Poly(I:C)-VHSV 4. In contrast, the survival rates of the groups administered the formalin-treated VHSV at a dose of 10(6), 10(5), and 10(4) TCID50 100 μL(-1) fish(-1) (DEPC-FT VHSV 6, DEPC-FT VHSV 5, and DEPC-FT VHSV 4) were only 8%, 12%, and 12%, respectively. The differences in the survival rates of the formalin-treated vaccine groups in trial I and trial II were attributed to the difference in the formalin-treatment period: the formalin-treated VHSV administered in trial I was not completely inactivated and worked as a live vaccine, which explains the 80% survival rate against VHSV challenge. Specific antibodies against VHSV were detected in sera from all vaccinated survivors, except the DEPC-VHSV 4 group. Furthermore, the specific antibody titers of fish vaccinated with the live and dead VHSV vaccines were similar, but the protective effects of the live and dead vaccines varied considerably. Our findings show that Poly(I:C) immunization with the live vaccine offers better protection than the formalin-treated vaccine against VHS in olive flounder and revealed that

  8. Systematic annotation and analysis of “virmugens” - virulence factors whose mutants can be used as live attenuated vaccines

    PubMed Central

    Racz, Rebecca; Chung, Monica; Xiang, Zuoshuang; He, Yongqun

    2012-01-01

    Live attenuated vaccines are usually generated by mutation of genes encoding virulence factors. “Virmugen” is coined here to represent a gene that encodes for a virulent factor of a pathogen and has been proven feasible in animal models to make a live attenuated vaccine by knocking out this gene. Not all virulence factors are virmugens. VirmugenDB is a web-based virmugen database (http://www.violinet.org/virmugendb). Currently, VirmugenDB includes 225 virmugens that have been verified to be valuable for vaccine development against 57 bacterial, viral, and protozoan pathogens. Bioinformatics analysis has revealed significant patterns in virmugens. For example, 10 Gram-negative and one Gram-positive bacterial aroA genes are virmugens. A sequence analysis has revealed at least 50% of identities in the protein sequences of the 10 Gram-negative bacterial aroA virmugens. As a pathogen case study, Brucella virmugens were analyzed. Out of 15 verified Brucella virmugens, six are related to carbohydrate or nucleotide transport and metabolism, and two involving cell membrane biogenesis. In addition, 54 virmugens from 24 viruses and 12 virmugens from 4 parasites are also stored in VirmugenDB. Virmugens tend to involve metabolism of nutrients (e.g., amino acids, carbohydrates, and nucleotides) and cell membrane formation. Host genes whose expressions were regulated by virmugen mutation vaccines or wild type virulent pathogens have also been annotated and systematically compared. The bioinformatics annotation and analysis of virmugens helps elucidate enriched virmugen profiles and the mechanisms of protective immunity, and further supports rational vaccine design. PMID:23219434

  9. Attempt to develop live attenuated bacterial vaccines by selecting resistance to gossypol, proflavine hemisulfate, novobiocin, or ciprofloxacin.

    PubMed

    Pridgeon, Julia W; Klesius, Phillip H; Yildirim-Aksoy, Mediha

    2013-04-26

    In an attempt to develop attenuated bacteria as potential live vaccines, four chemicals (gossypol, proflavine hemisulfate, novobiocin, and ciprofloxacin) were used to modify the following four genera of bacteria through chemical-resistance strategy: (1) Aeromonas hydrophila (9 isolates); (2) Edwardsiella tarda (9 isolates); (3) Streptococcus iniae (9 isolates); and (4) S. agalactiae (11 isolates). All bacteria used in this study were able to develop high resistance to gossypol. However, only some bacteria were able to develop resistance to proflavine hemisulfate, novobiocin, or ciprofloxacin. When the virulence of resistant bacteria was tested in tilapia or catfish, none of the gossypol-resistant isolate was attenuated, whereas majority of the proflavine hemisulfate-resistant isolates were attenuated. However, all proflavine hemisulfate-attenuated bacteria failed to provide significant protection to fish. Eight novobiocin- or ciprofloxacin-resistant Gram-positive bacteria (S. agalactiae and S. inaie) were found to be attenuated. However, none of them offered protection higher than 70%. Of seven attenuated novobiocin- or ciprofloxacin-resistant Gram-negative isolates (A. hydrophila and E. tarda), only one (novobiocin-resistant E. tarda 30305) was found to safe and highly efficacious. When E. tarda 30305-novo vaccinated Nile tilapia were challenged by its virulent E. tarda 30305, relative percent of survival of vaccinated fish at 14- and 28-days post vaccination (dpv) was 100% and 92%, respectively. Similarly, E. tarda 30305-novo offered 100% protection to channel catfish against challenges with virulent parent isolate E. tarda 30305 at both 14- and 28-dpv. Our results suggest that the development of live attenuated bacterial vaccines that are safe and efficacious is challenging, although it is feasible.

  10. Role of Occult and Post-acute Phase Replication in Protective Immunity Induced with a Novel Live Attenuated SIV Vaccine

    PubMed Central

    Ham, Claire; Ferguson, Deborah; Tudor, Hannah; Mattiuzzo, Giada; Klaver, Bep; Page, Mark; Stebbings, Richard; Das, Atze T.; Berkhout, Ben; Almond, Neil; Cranage, Martin P.

    2016-01-01

    In order to evaluate the role of persisting virus replication during occult phase immunisation in the live attenuated SIV vaccine model, a novel SIVmac239Δnef variant (SIVrtTA) genetically engineered to replicate in the presence of doxycycline was evaluated for its ability to protect against wild-type SIVmac239. Indian rhesus macaques were vaccinated either with SIVrtTA or with SIVmac239Δnef. Doxycycline was withdrawn from 4 of 8 SIVrtTA vaccinates before challenge with wild-type virus. Unvaccinated challenge controls exhibited ~107 peak plasma viral RNA copies/ml persisting beyond the acute phase. Six vaccinates, four SIVmac239Δnef and two SIVrtTA vaccinates exhibited complete protection, defined by lack of wild-type viraemia post-challenge and virus-specific PCR analysis of tissues recovered post-mortem, whereas six SIVrtTA vaccinates were protected from high levels of viraemia. Critically, the complete protection in two SIVrtTA vaccinates was associated with enhanced SIVrtTA replication in the immediate post-acute vaccination period but was independent of doxycycline status at the time of challenge. Mutations were identified in the LTR promoter region and rtTA gene that do not affect doxycycline-control but were associated with enhanced post-acute phase replication in protected vaccinates. High frequencies of total circulating CD8+T effector memory cells and a higher total frequency of SIV-specific CD8+ mono and polyfunctional T cells on the day of wild-type challenge were associated with complete protection but these parameters were not predictive of outcome when assessed 130 days after challenge. Moreover, challenge virus-specific Nef CD8+ polyfunctional T cell responses and antigen were detected in tissues post mortem in completely-protected macaques indicating post-challenge control of infection. Within the parameters of the study design, on-going occult-phase replication may not be absolutely required for protective immunity. PMID:28002473

  11. Purification and properties of Cu-Zn superoxide dismutase extracted from Brucella abortus strain 19

    SciTech Connect

    Tabatabai, L.B. )

    1991-03-11

    Recent work showed that a recombinant 20 kDa protein from Brucella abortus expressed in E. coli is a Cu-Zn superoxide dismutase (SOD). Western blot and ELISA results indicated that cattle with brucellosis have antibody to SOD. Here the authors report the purification and properties of the native B. abortus Cu-Zn SOD. SOD was extracted from methanol-killed Brucella abortus strain 19 with 0.1 M sodium citrate-1.0 M sodium chloride solution. The extract was dialyzed and protein precipitated by ammonium sulfate at 70-100% saturation was collected. The SOD was purified by HPLC anion exchange chromatography. SOD activity was assayed with a coupled enzyme assay using xanthine oxidase-cytochrome C reduction assay. The authors determined that the Brucella SOD is present in two molecular forms both inhibitable with KCN with Ki's of 0.32 mM and 4.98 mM, respectively. No other form of SOD was identified in the extract. Polyclonal antibody to SOD and polyclonal antibody to SOD synthetic peptide residues 134-143 inhibited SOD activity by 50% and 13%, respectively. Both SOD and the synthetic peptide inhibited binding of anti-SOD antibody to SOD by 60% and 20%, respectively. Based on these results the SOD and its amphipathic peptide will be considered as candidates for the design of synthetic multiple peptide vaccines and diagnostic reagents for bovine brucellosis.

  12. Effect of genotype specific live recombinant Newcastle disease vaccines on virus shedding after challenge

    Technology Transfer Automated Retrieval System (TEKTRAN)

    All Newcastle disease viruses (NDVs) are part of a single serotype; however, current vaccine strains display between 15 and 18% amino acid differences at the F and HN protein compared with current virulent viruses. Previous studies have shown that increased amino acid similarity between NDV vaccine...

  13. The live attenuated dengue vaccine TV003 elicits complete protection against dengue in a human challenge model.

    PubMed

    Kirkpatrick, Beth D; Whitehead, Stephen S; Pierce, Kristen K; Tibery, Cecilia M; Grier, Palmtama L; Hynes, Noreen A; Larsson, Catherine J; Sabundayo, Beulah P; Talaat, Kawsar R; Janiak, Anna; Carmolli, Marya P; Luke, Catherine J; Diehl, Sean A; Durbin, Anna P

    2016-03-16

    A dengue human challenge model can be an important tool to identify candidate dengue vaccines that should be further evaluated in large efficacy trials in endemic areas. Dengue is responsible for about 390 million infections annually. Protective efficacy results for the most advanced dengue vaccine candidate (CYD) were disappointing despite its ability to induce neutralizing antibodies against all four dengue virus (DENV) serotypes. TV003 is a live attenuated tetravalent DENV vaccine currently in phase 2 evaluation. To better assess the protective efficacy of TV003, a randomized double-blind, placebo-controlled trial in which recipients of TV003 or placebo were challenged 6 months later with a DENV-2 strain, rDEN2Δ30, was conducted. The primary endpoint of the trial was protection against dengue infection, defined as rDEN2Δ30 viremia. Secondary endpoints were protection against rash and neutropenia. All 21 recipients of TV003 who were challenged with rDEN2Δ30 were protected from infection with rDEN2Δ30. None developed viremia, rash, or neutropenia after challenge. In contrast, 100% of the 20 placebo recipients who were challenged with rDEN2Δ30 developed viremia, 80% developed rash, and 20% developed neutropenia. TV003 induced complete protection against challenge with rDEN2Δ30 administered 6 months after vaccination. TV003 will be further evaluated in dengue-endemic areas. The controlled dengue human challenge model can accelerate vaccine development by evaluating the protection afforded by the vaccine, thereby eliminating poor candidates from further consideration before the initiation of large efficacy trials.

  14. Human transcriptome response to immunization with live-attenuated Venezuelan equine encephalitis virus vaccine (TC-83): Analysis of whole blood

    PubMed Central

    Erwin-Cohen, Rebecca A.; Porter, Aimee I.; Pittman, Phillip R.; Rossi, Cynthia A.; DaSilva, Luis

    2017-01-01

    ABSTRACT Venezuelan equine encephalitis virus (VEEV) is an important human and animal alphavirus pathogen transmitted by mosquitoes. The virus is endemic in Central and South America, but has also caused equine outbreaks in southwestern areas of the United States. In an effort to better understand the molecular mechanisms of the development of immunity to this important pathogen, we performed transcriptional analysis from whole, unfractionated human blood of patients who had been immunized with the live-attenuated vaccine strain of VEEV, TC-83. We compared changes in the transcriptome between naïve individuals who were mock vaccinated with saline to responses of individuals who received TC-83. Significant transcriptional changes were noted at days 2, 7, and 14 following vaccination. The top canonical pathways revealed at early and intermediate time points (days 2 and 7) included the involvement of the classic interferon response, interferon-response factors, activation of pattern recognition receptors, and engagement of the inflammasome. By day 14, the top canonical pathways included oxidative phosphorylation, the protein ubiquitination pathway, natural killer cell signaling, and B-cell development. Biomarkers were identified that differentiate between vaccinees and control subjects, at early, intermediate, and late stages of the development of immunity as well as markers which were common to all 3 stages following vaccination but distinct from the sham-vaccinated control subjects. The study represents a novel examination of molecular processes that lead to the development of immunity against VEEV in humans and which may be of value as diagnostic targets, to enhance modern vaccine design, or molecular correlates of protection. PMID:27870591

  15. Potential for a live red seabream iridovirus (RSIV) vaccine in rock bream Oplegnathus fasciatus at a low rearing temperature.

    PubMed

    Oh, So-Young; Oh, Myung-Joo; Nishizawa, Toyohiko

    2014-01-09

    Serious economic losses have occurred in fingerlings and market-sized rock bream Oplegnathus fasciatus in Korea due to red seabream iridovirus (RSIV) infection. We demonstrated previously that viral multiplication in fish is downregulated by maintaining fish at far from optimum temperatures at the onset of disease. We applied this concept to develop a live RSIV vaccine in rock bream. Mortalities in rock bream that were inoculated with RSIV and reared at 21-30°C were ≥90%, whereas no mortality was observed in fish that received an RSIV inoculation and were reared at ≤18°C. RSIV kinetics revealed that RSIV multiplied rapidly in fish reared at 24.3±1.3°C, and achieved the critical level for rock bream (approximately 10(9.0) genomes/mg) within 28 days. In contrast, the RSIV genome was detected on day 10 in fish that received an RSIV inoculation at 15.5°C, and peaked on day 28 at 10(5.91±0.54) genomes/mg, then decreasing gradually, and were then maintained under the detection level beginning on day 84 after RSIV inoculation. Furthermore, the fish surviving the RSIV infection at low rearing temperature were strongly protected from re-challenge with homologous RSIV; the threshold level of RSIV for rock bream to mount a protective immune response was ≤10(5.4) genomes/mg. Cohabitation experiments revealed that the spread of RSIV from rock bream vaccinated with a live RSIV could be low if it is limited to fish in the late stage (≥84 days of elapse) after vaccination. Thus, it was concluded that when rock bream are reared at ≤18°C and inoculated with RSIV, the survivors can mount a protective immune response against RSIV, suggesting a positive effect of a live RSIV vaccine for rock bream.

  16. Generation of a live rabies vaccine strain attenuated by multiple mutations and evaluation of its safety and efficacy.

    PubMed

    Nakagawa, Keisuke; Ito, Naoto; Masatani, Tatsunori; Abe, Masako; Yamaoka, Satoko; Ito, Yuki; Okadera, Kota; Sugiyama, Makoto

    2012-05-21

    An amino acid substitution at position 333 in rabies virus G protein is known to determine the pathogenicity: strains with Arg or Lys at that position kill adult mice after intracerebral inoculation, whereas strains with other amino acids cause non-lethal infection. Based on those findings, attenuated rabies virus strains have been established and used for oral vaccines mainly for wild animals. However, considering the possibility of back-mutation to the virulent phenotype, a strain that is attenuated by multiple mutations not only in the G protein but also in other viral proteins would be more appropriate as a safe live vaccine. We previously demonstrated that the fixed rabies virus Ni-CE strain, which causes only transient body weight loss in adult mice after intracerebral inoculation, is mainly attenuated by mutations in the N, P and M proteins, while this strain has virulent-type Arg at position 333 in the G protein. In this study, to obtain a live vaccine strain that is attenuated by multiple mutations, we generated Ni-CE mutant, Ni-CE(G333Glu) strain, which has an Arg-to-Glu mutation at position 333 in the G protein, and examined its pathogenicity and immunogenicity. We found that, in contrast to Ni-CE strain, Ni-CE(G333Glu) strain did not cause transient body weight loss in adult mice after intracerebral inoculation. The attenuated phenotype of Ni-CE(G333Glu) strain did not change even after 10 serial intracerebral passages in suckling mice. We also demonstrated that inoculation of Ni-CE(G333Glu) strain induced virus-neutralizing antibody in immunized mice and protected the mice from lethal challenge. These results indicate that Ni-CE(G333Glu) strain is a promising candidate for development of a live rabies vaccine with a high safety level.

  17. Aged mice display an altered pulmonary host response to Francisella tularensis live vaccine strain (LVS) infections

    PubMed Central

    CA, Mares; SS, Ojeda; Q, Li; EG, Morris; JJ, Coalson; JM, Teale

    2012-01-01

    Aging is a complex phenomenon that has been shown to affect many organ systems including the innate and adaptive immune systems. The current study was designed to examine the potential effect of immunosenescence on the pulmonary immune response using a Francisella tularensis live vaccine strain (LVS) inhalation infection model. F. tularensis is a gram-negative intracellular pathogen that can cause a severe pneumonia.In this study both young (8-12 week old) and aged (20-24 month old) mice were infected intranasally with LVS. Lung tissues from young and aged mice were used to assess pathology, recruitment of immune cell types and cytokine expression levels at various times post infection. Bacterial burdens were also assessed. Interestingly, the lungs of aged animals harbored fewer organisms at early time points of infection (day 1, day 3) compared with their younger counterparts. In addition, only aged animals displayed small perivascular aggregates at these early time points that appeared mostly mononuclear in nature. However, the kinetics of infiltrating polymorphonuclear neutrophils (PMNs) and increased cytokine levels measured in the bronchial alveolar lavage fluid (BALF) were delayed in infected aged animals relative to young infected animals with neutrophils appearing at day 5 post infection (PI) in the aged animals as opposed to day 3 PI in the young infected animals. Also evident were alterations in the ratios of mononuclear to PMNs at distinct post infection times. The above evidence indicates that aged mice elicit an altered immune response in the lung to respiratory Francisella tularensis LVS infections compared to their younger counterparts. PMID:19825409

  18. GroEL and Lipopolysaccharide from Francisella tularensis Live Vaccine Strain Synergistically Activate Human Macrophages ▿

    PubMed Central

    Noah, Courtney E.; Malik, Meenakshi; Bublitz, DeAnna C.; Camenares, Devin; Sellati, Timothy J.; Benach, Jorge L.; Furie, Martha B.

    2010-01-01

    Francisella tularensis, the causative agent of tularemia, interacts with host cells of innate immunity in an atypical manner. For most Gram-negative bacteria, the release of lipopolysaccharide (LPS) from their outer membranes stimulates an inflammatory response. When LPS from the attenuated live vaccine strain (LVS) or the highly virulent Schu S4 strain of F. tularensis was incubated with human umbilical vein endothelial cells, neither species of LPS induced expression of the adhesion molecule E-selectin or secretion of the chemokine CCL2. Moreover, a high concentration (10 μg/ml) of LVS or Schu S4 LPS was required to stimulate production of CCL2 by human monocyte-derived macrophages (huMDM). A screen for alternative proinflammatory factors of F. tularensis LVS identified the heat shock protein GroEL as a potential candidate. Recombinant LVS GroEL at a concentration of 10 μg/ml elicited secretion of CXCL8 and CCL2 by huMDM through a TLR4-dependent mechanism. When 1 μg of LVS GroEL/ml was added to an equivalent amount of LVS LPS, the two components synergistically activated the huMDM to produce CXCL8. Schu S4 GroEL was less stimulatory than LVS GroEL and showed a lesser degree of synergy when combined with Schu S4 LPS. These findings suggest that the intrinsically low proinflammatory activity of F. tularensis LPS may be increased in the infected human host through interactions with other components of the bacterium. PMID:20123721

  19. Biology of Francisella tularensis Subspecies holarctica Live Vaccine Strain in the Tick Vector Dermacentor variabilis

    PubMed Central

    Mani, Rinosh J.; Reichard, Mason V.; Morton, Rebecca J.; Kocan, Katherine M.; Clinkenbeard, Kenneth D.

    2012-01-01

    Background The γ-proteobacterium Francisella tularensis is the etiologic agent of seasonal tick-transmitted tularemia epizootics in rodents and rabbits and of incidental infections in humans. The biology of F. tularensis in its tick vectors has not been fully described, particularly with respect to its quanta and duration of colonization, tissue dissemination, and transovarial transmission. A systematic study of the colonization of Dermacentor variabilis by the F. tularensis subsp. holarctica live vaccine strain (LVS) was undertaken to better understand whether D. variabilis may serve as an inter-epizootic reservoir for F. tularensis. Methodology/Principal Findings Colony-reared larva, nymph, and adult D. variabilis were artificially fed LVS via glass capillary tubes fitted over the tick mouthparts, and the level of colonization determined by microbial culture. Larvae and nymphs were initially colonized with 8.8±0.8×101 and 1.1±0.03×103 CFU/tick, respectively. Post-molting, a significant increase in colonization of both molted nymphs and adults occurred, and LVS persisted in 42% of molted adult ticks at 126 days post-capillary tube feeding. In adult ticks, LVS initially colonized the gut, disseminated to hemolymph and salivary glands by 21 days, and persisted up to 165 days. LVS was detected in the salivary secretions of adult ticks after four days post intra-hemocoelic inoculation, and LVS recovered from salivary gland was infectious to mice with an infectious dose 50% of 3 CFU. LVS in gravid female ticks colonized via the intra-hemocoelic route disseminated to the ovaries and then to the oocytes, but the pathogen was not recovered from the subsequently-hatched larvae. Conclusions/Significance This study demonstrates that D. variabilis can be efficiently colonized with F. tularensis using artificial methods. The persistence of F. tularensis in D. variabilis suggests that this tick species may be involved in the maintenance of enzootic foci of tularemia in the

  20. Oral Fluids as a Live-Animal Sample Source for Evaluating Cross-Reactivity and Cross-Protection following Intranasal Influenza A Virus Vaccination in Pigs.

    PubMed

    Hughes, Holly R; Vincent, Amy L; Brockmeier, Susan L; Gauger, Phillip C; Pena, Lindomar; Santos, Jefferson; Braucher, Douglas R; Perez, Daniel R; Loving, Crystal L

    2015-10-01

    In North American swine, there are numerous antigenically distinct H1 influenza A virus (IAV) variants currently circulating, making vaccine development difficult due to the inability to formulate a vaccine that provides broad cross-protection. Experimentally, live-attenuated influenza virus (LAIV) vaccines demonstrate increased cross-protection compared to inactivated vaccines. However, there is no standardized assay to predict cross-protection following LAIV vaccination. Hemagglutination-inhibiting (HI) antibody in serum is the gold standard correlate of protection following IAV vaccination. LAIV vaccination does not induce a robust serum HI antibody titer; however, a local mucosal antibody response is elicited. Thus, a live-animal sample source that could be used to evaluate LAIV immunogenicity and cross-protection is needed. Here, we evaluated the use of oral fluids (OF) and nasal wash (NW) collected after IAV inoculation as a live-animal sample source in an enzyme-linked immunosorbent assay (ELISA) to predict cross-protection in comparison to traditional serology. Both live-virus exposure and LAIV vaccination provided heterologous protection, though protection was greatest against more closely phylogenetically related viruses. IAV-specific IgA was detected in NW and OF samples and was cross-reactive to representative IAV from each H1 cluster. Endpoint titers of cross-reactive IgA in OF from pigs exposed to live virus was associated with heterologous protection. While LAIV vaccination provided significant protection, LAIV immunogenicity was reduced compared to live-virus exposure. These data suggest that OF from pigs inoculated with wild-type IAV, with surface genes that match the LAIV seed strain, could be used in an ELISA to assess cross-protection and the antigenic relatedness of circulating and emerging IAV in swine.

  1. Comparative analysis of the immunologic response induced by the Sterne 34F2 live spore Bacillus anthracis vaccine in a ruminant model.

    PubMed

    Ndumnego, Okechukwu C; Köhler, Susanne M; Crafford, Jannie; van Heerden, Henriette; Beyer, Wolfgang

    2016-10-01

    The Sterne 34F2 live spore vaccine (SLSV) developed in 1937 is the most widely used veterinary vaccine against anthrax. However, literature on the immunogenicity of this vaccine in a target ruminant host is scarce. In this study, we evaluated the humoral response to the Bacillus anthracis protective antigen (rPA), a recombinant bacillus collagen-like protein of anthracis (rBclA), formaldehyde inactivated spores (FIS) prepared from strain 34F2 and a vegetative antigen formulation prepared from a capsule and toxin deficient strain (CDC 1014) in Boer goats. The toxin neutralizing ability of induced antibodies was evaluated using an in vitro toxin neutralization assay. The protection afforded by the vaccine was also assessed in vaccinates. Anti-rPA, anti-FIS and lethal toxin neutralizing titres were superior after booster vaccinations, compared to single vaccinations. Qualitative analysis of humoral responses to rPA, rBclA and FIS antigens revealed a preponderance of anti-FIS IgG titres following either single or double vaccinations with the SLSV. Antibodies against FIS and rPA both increased by 350 and 300-fold following revaccinations respectively. There was no response to rBclA following vaccinations with the SLSV. Toxin neutralizing titres increased by 80-fold after single vaccination and 700-fold following a double vaccination. Lethal challenge studies in naïve goats indicated a minimum infective dose of 36 B. anthracis spores. Single and double vaccination with the SLSV protected 4/5 and 3/3 of goats challenged with>800 spores respectively. An early booster vaccination following the first immunization is suggested in order to achieve a robust immunity. Results from this study indicate that this crucial second vaccination can be administered as early as 3 months after the initial vaccination.

  2. Evaluation of two live attenuated cold-adapted H5N1 influenza virus vaccines in healthy adults

    PubMed Central

    Karron, Ruth A.; Talaat, Kawsar; Luke, Catherine; Callahan, Karen; Thumar, Bhagvanji; DiLorenzo, Susan; McAuliffe, Josephine; Schappell, Elizabeth; Suguitan, Amorsolo; Mills, Kimberly; Chen, Grace; Lamirande, Elaine; Coelingh, Kathleen; Jin, Hong; Murphy, Brian R.; Kemble, George; Subbarao, Kanta

    2016-01-01

    Background Development of live attenuated influenza vaccines (LAIV) against avian viruses with pandemic potential is an important public health strategy. Methods and Findings We performed open-label trials to evaluate the safety, infectivity, and immunogenicity of H5N1 VN 2004 AA ca and H5N1 HK 2003 AA ca. Each of these vaccines contains a modified H5 hemagglutinin and unmodified N1 neuraminidase from the respective wild-type (wt) parent virus and the six internal protein gene segments of the A/Ann Arbor/6/60 cold-adapted (ca) master donor virus. The H5N1 VN 2004 AA ca vaccine virus was evaluated at dosages of 106.7 TCID50 and 107.5 TCID50, and the H5N1 HK 2003 AA ca vaccine was evaluated at a dosage of 107.5 TCID50. Two doses were administered intranasally to healthy adults in isolation at 4 to 8 week intervals. Vaccine safety was assessed through daily examinations and infectivity was assessed by viral culture and by realtime reverse transcription-polymerase chain reaction testing of nasal wash (NW) specimens. Immunogenicity was assessed by measuring hemagglutination-inhibition (HI) antibodies, neutralizing antibodies, and IgG or IgA antibodies to recombinant (r)H5 VN 2004 hemagglutinin (HA) in serum or NW. Fifty-nine participants were enrolled: 21 received 106.7 TCID50 and 21 received 107.5 TCID50 of H5N1 VN 2004 AA ca and 17 received H5N1 HK 2003 AA ca. Shedding of vaccine virus was minimal, as were HI and neutralizing antibody responses. Fifty-two percent of recipients of 107.5 TCID50 of H5N1 VN 2004 AA ca developed a serum IgA response to rH5 VN 2004 HA. Conclusions The live attenuated H5N1 VN 2004 and HK 2003 AA ca vaccines bearing avian H5 HA antigens were very restricted in replication and were more attenuated than seasonal LAIV bearing human H1, H3 or B HA antigens. The H5N1 AA ca LAIV elicited serum ELISA antibody but not HI or neutralizing antibody responses in healthy adults. (ClinicalTrials.gov Identifiers: NCT00347672 and NCT00488046). PMID:19540952

  3. Protective role of antibodies induced by Brucella melitensis B115 against B. melitensis and Brucella abortus infections in mice.

    PubMed

    Adone, Rosanna; Francia, Massimiliano; Pistoia, Claudia; Petrucci, Paola; Pesciaroli, Michele; Pasquali, Paolo

    2012-06-08

    It has been demonstrated that antibodies specific for O-PS antigen of Brucella smooth strains are involved in the protective immunity of brucellosis. Since the rough strain Brucella melitensis B115 was able to protect mice against wild Brucella strains brucellosis despite the lack of anti-OPS antibodies, in this study we evaluated the biological significance of antibodies induced by this strain, directed to antigens other than O-PS, passively tranferred to untreated mice prior to infection with Brucella abortus 2308 and B. melitensis 16M virulent strains. The protective ability of specific antisera collected from mice vaccinated with B. melitensis B115, B. abortus RB51 and B. abortus S19 strains was compared. The results indicated that antibodies induced by B115 were able to confer a satisfactory protection, especially against B. abortus 2308, similar to that conferred by the antiserum S19, while the RB51 antiserum was ineffective. These findings suggest that antibodies induced by B115 could act as opsonins as well as antibodies anti-O-PS, thus triggering more efficient internalization and degradation of bacteria within phagocytes. This is the first study assessing the efficacy of antibodies directed to antigens other than O-PS in the course of brucellosis infection.

  4. A post-marketing surveillance study of a human live-virus pandemic influenza A (H1N1) vaccine (Nasovac (®) ) in India.

    PubMed

    Kulkarni, Prasad S; Raut, Sidram K; Dhere, Rajeev M

    2013-01-01

    A live attenuated pandemic H1N1 influenza vaccine was developed in India. A post marketing surveillance was conducted retrospectively in healthy individuals (³ 3 years) who were vaccinated intranasally around one year before. After consent, the subjects recorded adverse events developing within 42 days. Among 7565 individuals (3 - 85 years), a total of 81 solicited adverse reactions (1%) were reported in 49 subjects (0.65%). The reactions included mild to moderate respiratory symptoms. No H1N1 case was encountered during one year postvaccination. The data show the safety of the live attenuated influenza vaccine platform developed in India.

  5. Do Maternal Living Arrangements Influence the Vaccination Status of Children Age 12–23 Months? A Data Analysis of Demographic Health Surveys 2010–11 from Zimbabwe

    PubMed Central

    Rossi, Rodolfo

    2015-01-01

    Introduction Although vaccination is an effective intervention to reduce childhood mortality and morbidity, reasons for incomplete vaccination, including maternal living arrangements, have been marginally explored. This study aims at assessing whether maternal living arrangements are associated with vaccination status of children aged 12–23 months in Zimbabwe. It also explores other variables that may be associated with having children not fully vaccinated. Materials and Methods A cross-sectional analysis was performed on the DHS-VI done in Zimbabwe in 2010–2011 (response rate 93%). Incomplete vaccination of children (outcome), was defined as not having received one dose of BCG and measles, 3 doses of polio and DPT/Pentavalent. Maternal living arrangements (main exposure), and other exposure variables were analysed. Survey logistic regression was used to calculate crude and adjusted OR for exposures against the outcome. Results The dataset included 1,031 children aged 12–23 months. 65.8% of children were fully vaccinated. 65.7% of the mothers were married and cohabitating with a partner, 20.3% were married/partnered but living separately and 14% were not married. Maternal living arrangements were not associated with the vaccination status of children both in crude and adjusted analysis. Factors associated with poorer vaccination status of the children included: no tetanus vaccination for mothers during pregnancy (adjusted OR = 2.1, 95%CI 1.5;3.0), child living away from mother (adjusted OR = 1.5, 95%CI 1.2;1.8), mother’s education (adjusted OR = 0.6, 95%CI 0.4;0.9), high number of children living in the household (adjusted OR = 1.5, 95%CI 1.1;2.2), child age (adjusted OR = 0.7, 95%CI 0.5;0.9). Discussion Maternal living arrangements were not associated with vaccination status of Zimbabwean children. Other factors, such as the mother’s health-seeking behaviour and education were major factors associated with the children’s vaccination status. Given the

  6. Neutrophils rapidly migrate via lymphatics after Mycobacterium bovis BCG intradermal vaccination and shuttle live bacilli to the draining lymph nodes.

    PubMed

    Abadie, Valérie; Badell, Edgar; Douillard, Patrice; Ensergueix, Danielle; Leenen, Pieter J M; Tanguy, Myriam; Fiette, Laurence; Saeland, Sem; Gicquel, Brigitte; Winter, Nathalie

    2005-09-01

    The early innate response after Mycobacterium bovis bacille Calmette-Guérin (BCG) vaccination is poorly characterized but probably decisive for subsequent protective immunity against tuberculosis. Therefore, we vaccinated mice with fluorescent BCG strains in the ear dorsum, as a surrogate of intradermal vaccination in humans. During the first 3 days, we tracked BCG host cells migrating out of the dermis to the auricular draining lymph nodes (ADLNs). Resident skin dendritic cells (DCs) or macrophages did not play a predominant role in early BCG capture and transport to ADLNs. The main BCG host cells rapidly recruited both in the dermis and ADLNs were neutrophils. Fluorescent green or red BCG strains injected into nonoverlapping sites were essentially sheltered by distinct neutrophils in the ADLN capsule, indicating that neutrophils had captured bacilli in peripheral tissue and transported them to the lymphoid organ. Strikingly, we observed BCG-infected neutrophils in the lumen of lymphatic vessels by confocal microscopy on ear dermis. Fluorescence-labeled neutrophils injected into the ears accumulated exclusively into the ipsilateral ADLN capsule after BCG vaccination. Thus, we provide in vivo evidence that neutrophils, like DCs or inflammatory monocytes, migrate via afferent lymphatics to lymphoid tissue and can shuttle live microorganisms.

  7. Epidemiology of Brucellosis and Genetic Diversity of Brucella abortus in Kazakhstan

    PubMed Central

    Shevtsova, Elena; Shevtsov, Alexandr; Mukanov, Kasim; Filipenko, Maxim; Kamalova, Dinara; Sytnik, Igor; Syzdykov, Marat; Kuznetsov, Andrey; Akhmetova, Assel; Zharova, Mira; Karibaev, Talgat; Tarlykov, Pavel; Ramanculov, Erlan

    2016-01-01

    Brucellosis is a major zoonotic infection in Kazakhstan. However, there is limited data on its incidence in humans and animals, and the genetic diversity of prevalent strains is virtually unstudied. Additionally, there is no detailed overview of Kazakhstan brucellosis control and eradication programs. Here, we analyzed brucellosis epidemiological data, and assessed the effectiveness of eradication strategies employed over the past 70 years to counteract this infection. We also conducted multiple loci variable-number tandem repeat analysis (MLVA) of Brucella abortus strains found in Kazakhstan. We analyzed official data on the incidence of animal brucellosis in Kazakhstan. The records span more than 70 years of anti-brucellosis campaigns, and contain a brief description of the applied control strategies, their effectiveness, and their impact on the incidence in humans. The MLVA-16 method was used to type 94 strains of B. abortus and serial passages of B. abortus 82, a strain used in vaccines. MLVA-8 and MLVA-11 analyses clustered strains into a total of four and seven genotypes, respectively; it is the first time that four of these genotypes have been described. MLVA-16 analysis divided strains into 28 distinct genotypes having genetic similarity coefficient that varies from 60 to100% and a Hunter & Gaston diversity index of 0.871. MST analysis reconstruction revealed clustering into "Kazakhstani-Chinese (Central Asian)", "European" and "American" lines. Detection of multiple genotypes in a single outbreak confirms that poorly controlled trade of livestock plays a crucial role in the spread of infection. Notably, the MLVA-16 profile of the B. abortus 82 strain was unique and did not change during 33 serial passages. MLVA genotyping may thus be useful for epidemiological monitoring of brucellosis, and for tracking the source(s) of infection. We suggest that countrywide application of MLVA genotyping would improve the control of brucellosis in Kazakhstan. PMID

  8. Infection-enhancing lipopeptides do not improve intranasal immunization of cotton rats with a delta-G candidate live-attenuated human respiratory syncytial virus vaccine.

    PubMed

    Tien Nguyen, D; Boes, Jolande; van Amerongen, Geert; van Remmerden, Yvonne; Yüksel, Selma; Guichelaar, Teun; Osterhaus, Albert D M E; de Swart, Rik L

    2013-12-01

    Development of live-attenuated human respiratory syncytial virus (HRSV) vaccines has proven to be difficult. Several vaccine candidates were found to be over-attenuated and displayed limited immunogenicity. Recently, we identified three synthetic cationic lipopeptides that enhanced paramyxovirus infections in vitro. The infection enhancement proved to be mediated by enhanced virus binding to target cells. We hypothesized that these lipopeptides can be used as adjuvants to promote immune responses induced by live-attenuated paramyxovirus vaccines. This hypothesis was tested in a vaccination and challenge model in cotton rats, using a previously described recombinant live-attenuated candidate HRSV vaccine lacking the gene encoding the G glycoprotein (rHRSVΔG). Surprisingly, intranasal vaccination of cotton rats with rHRSVΔG formulated in infection-enhancing lipopeptides resulted in reduced virus loads in nasopharyngeal lavages, reduced seroconversion levels and reduced protection from wild-type HRSV challenge. In conclusion, we were unable to demonstrate the feasibility of lipopeptides as adjuvants for a candidate live-attenuated HRSV vaccine in the cotton rat model.

  9. Canine infectious tracheobronchitis: effects of an intranasal live canine parainfluenza-Bordetella bronchiseptica vaccine on viral shedding and clinical tracheobronchitis (kennel cough).

    PubMed

    Kontor, E J; Wegrzyn, R J; Goodnow, R A

    1981-10-01

    A modified-live intranasal (IN) canine parainfluenza (CPI)-virus Bordetella bronchiseptica vaccine was evaluated in dogs for efficacy against laboratory-induced canine infectious tracheobronchitis. The comparative efficacies of IN and parenteral administrations of the CPI virus fraction were also evaluated. The frequency and duration of clinical tracheobronchitis, blood serum agglutination titer, humoral antibody response, and duration of CPI virus and B bronchiseptica shedding were measured. Group A dogs were vaccinated subcutaneously or IM with an experimental CPI vaccine and challenge exposed with CPI virus. Group B dogs were vaccinated IN with avirulent CPI virus-B bronchiseptica live antigens and challenge exposed with virulent CPI virus and virulent B bronchiseptica. The IN vaccination (group B) significantly reduced (P less than or equal to 0.001) the occurrence of clinical tracheobronchitis by 96%. The combined challenge exposure of virulent CPI and virulent B bronchiseptica produced a synergistic enhancement of the clinical signs of kennel cough. The percentage of days after challenge exposure that virus shedding was detected for controls equaled 70% as compared with 50% and only 1% for parenterally and IN vaccinated dogs, respectively. Isolation of virulent B bronchiseptica microorganisms was reduced 89% in dogs vaccinated IN compared to controls. The geometric mean humoral antibody titers to CPI virus after 2 parenteral vaccinations and 1 IN vaccination were 1:43 and 1:34, respectively.

  10. An ecological perspective on the changing face of Brucella abortus in the western United States

    USGS Publications Warehouse

    Cross, Paul C.; Maichak, Eric J.; Brennan, Angela; Scurlock, Brandon M.; Henningsen, John C.; Luikart, Gordon

    2013-01-01

    After a hiatus during the 1990s, outbreaks of Brucella abortus in cattle are occurring more frequently in some of the western states of the United States, namely, Montana, Wyoming and Idaho. This increase is coincident with increasing brucellosis seroprevalence in elk (Cervus elaphus), which is correlated with elk density. Vaccines are a seductive solution, but their use in wildlife systems remains limited by logistical, financial, and scientific constraints. Cattle vaccination is ongoing in the region. Livestock regulations, however, tend to be based on serological tests that test for previous exposure and available vaccines do not protect against seroconversion. The authors review recent ecological studies of brucellosis, with particular emphasis on the Greater Yellowstone Area, and highlight the management options and implications of this work, including the potential utility of habitat modifications and targeted hunts, as well as scavengers and predators. Finally, the authors discuss future research directions that will help us to understand and manage brucellosis in wildlife.

  11. An ecological perspective on Brucella abortus in the western United States.

    PubMed

    Cross, P C; Maichak, E J; Brennan, A; Scurlock, B M; Henningsen, J; Luikart, G

    2013-04-01

    After a hiatus during the 1990s, outbreaks of Brucella abortus in cattle are occurring more frequently in some of the western states of the United States, namely, Montana, Wyoming and Idaho. This increase is coincidentwith increasing brucellosis seroprevalence in elk (Cervus elaphus), which is correlated with elk density. Vaccines are a seductive solution, but their use in wildlife systems remains limited by logistical, financial, and scientific constraints. Cattle vaccination is ongoing in the region. Livestock regulations, however, tend to be based on serological tests that test for previous exposure and available vaccines do not protect against seroconversion. The authors review recent ecological studies of brucellosis, with particular emphasis on the Greater Yellowstone Area, and highlight the management options and implications of this work, including the potential utility of habitat modifications and targeted hunts, as well as scavengers and predators. Finally, the authors discuss future research directions that will help us to understand and manage brucellosis in wildlife.

  12. Brucella abortus Cyclic β-1,2-Glucan Mutants Have Reduced Virulence in Mice and Are Defective in Intracellular Replication in HeLa Cells

    PubMed Central

    Briones, Gabriel; Iñón de Iannino, Nora; Roset, Mara; Vigliocco, Ana; Paulo, Patricia Silva; Ugalde, Rodolfo A.

    2001-01-01

    Null cyclic β-1,2-glucan synthetase mutants (cgs mutants) were obtained from Brucella abortus virulent strain 2308 and from B. abortus attenuated vaccinal strain S19. Both mutants show greater sensitivity to surfactants like deoxycholic acid, sodium dodecyl sulfate, and Zwittergent than the parental strains, suggesting cell surface alterations. Although not to the same extent, both mutants display reduced virulence in mice and defective intracellular multiplication in HeLa cells. The B. abortus S19 cgs mutant was completely cleared from the spleens of mice after 4 weeks, while the 2308 mutant showed a 1.5-log reduction of the number of brucellae isolated from the spleens after 12 weeks. These results suggest that cyclic β-1,2-glucan plays an important role in the residual virulence of the attenuated B. abortus S19 strain. Although the cgs mutant was cleared from the spleens earlier than the wild-type parental strain (B. abortus S19) and produced less inflammatory response, its ability to confer protection against the virulent strain B. abortus 2308 was fully retained. Equivalent levels of induction of spleen gamma interferon mRNA and anti-lipopolysaccharide (LPS) of immunoglobulin G2a (IgG2a) subtype antibodies were observed in mice injected with B. abortus S19 or the cgs mutant. However, the titer of anti-LPS antibodies of the IgG1 subtype induced by the cgs mutant was lower than that observed with the parental S19 strain, thus suggesting that the cgs mutant induces a relatively exclusive Th1 response. PMID:11401996

  13. Deep Sequencing of Distinct Preparations of the Live Attenuated Varicella-Zoster Virus Vaccine Reveals a Conserved Core of Attenuating Single-Nucleotide Polymorphisms

    PubMed Central

    Yamanishi, Koichi; Gomi, Yasuyuki; Gershon, Anne A.; Breuer, Judith

    2016-01-01

    ABSTRACT The continued success of the live attenuated varicella-zoster virus vaccine in preventing varicella-zoster and herpes zoster is well documented, as are many of the mutations that contribute to the attenuation of the vOka virus for replication in skin. At least three different preparations of vOka are marketed. Here, we show using deep sequencing of seven batches of vOka vaccine (including ZostaVax, VariVax, VarilRix, and the Oka/Biken working seed) from three different manufacturers (VariVax, GSK, and Biken) that 137 single-nucleotide polymorphism (SNP) mutations are present in all vaccine batches. This includes six sites at which the vaccine allele is fixed or near fixation, which we speculate are likely to be important for attenuation. We also show that despite differences in the vaccine populations between preparations, batch-to-batch variation is minimal, as is the number and frequency of mutations unique to individual batches. This suggests that the vaccine manufacturing processes are not introducing new mutations and that, notwithstanding the mixture of variants present, VZV live vaccines are extremely stable. IMPORTANCE The continued success of vaccinations to prevent chickenpox and shingles, combined with the extremely low incidence of adverse reactions, indicates the quality of these vaccines. The vaccine itself is comprised of a heterogeneous live attenuated virus population and thus requires deep-sequencing technologies to explore the differences and similarities in the virus populations between different preparations and batches of the vaccines. Our data demonstrate minimal variation between batches, an important safety feature, and provide new insights into the extent of the mutations present in this attenuated virus. PMID:27440875

  14. Construction of a live-attenuated HIV-1 vaccine through genetic code expansion.

    PubMed

    Wang, Nanxi; Li, Yue; Niu, Wei; Sun, Ming; Cerny, Ronald; Li, Qingsheng; Guo, Jiantao

    2014-05-05

    A safe and effective vaccine against human immunodeficiency virus type 1 (HIV-1) is urgently needed to combat the worldwide AIDS pandemic, but still remains elusive. The fact that uncontrolled replication of an attenuated vaccine can lead to regaining of its virulence creates safety concerns precluding many vaccines from clinical application. We introduce a novel approach to control HIV-1 replication, which entails the manipulation of essential HIV-1 protein biosynthesis through unnatural amino acid (UAA*)-mediated suppression of genome-encoded blank codon. We successfully demonstrate that HIV-1 replication can be precisely turned on and off in vitro.

  15. Risks associated with the use of live-attenuated vaccine poliovirus strains and the strategies for control and eradication of paralytic poliomyelitis.

    PubMed

    Pliaka, Vaia; Kyriakopoulou, Zaharoula; Markoulatos, Panayotis

    2012-05-01

    The Global Polio Eradication Initiative was launched in 1988 with the aim to eliminate paralytic poliomyelitis. Two effective vaccines are available: inactivated polio vaccine (IPV) and oral polio vaccine (OPV). Since 1964, OPV has been used instead of IPV in most countries due to several economic and biological advantages. However, in rare cases, the live-attenuated Sabin strains of OPV revert to neurovirulence and cause vaccine-associated paralytic poliomyelitis in vaccinees or lead to emergence of vaccine-derived poliovirus strains. Attenuating mutations and recombination events have been associated with the reversion of vaccine strains to neurovirulence. The substitution of OPV with an improved new-generation IPV and the availability of new specific drugs against polioviruses are considered as future strategies for outbreak control and the eradication of paralytic poliomyelitis worldwide.

  16. Clinical and serologic effects of Alice strain live attenuated influenza A (H3N2) virus vaccine in an adult population.

    PubMed

    Miller, L W; Togo, Y; Hornick, R B

    1975-12-30

    Alice strain live attenuated influenza A (H3N2) virus was evaluated in prison volunteers. By random double blind allocation, 94 volunteers received Alice strain vaccine (AS) intranasally and 97 received placebo. The vaccine was well tolerated, and there was no serious morbidity. The number, type, duration, and severity of symptoms was not significantly different between the vaccine and placebo groups. Seventy-five per cent of vaccines with initial HAI titers less than or equal to 1:8 had 4 fold or greater titer responses on day 30. Placebo recipients experienced no titer changes. The GMT among vaccinees increased from 23.5 prior to vaccination 59.7 30 days later. Surveillance activities failed to document influenza A (H3N2) infection in the volunteer population during a 6 month follow-up period. Additional studies on the protective effects of the vaccine are required before efficacy can be determined.

  17. Advantage of live attenuated cold-adapted influenza A virus over inactivated vaccine for A/Washington/80 (H3N2) wild-type virus infection.

    PubMed

    Clements, M L; Betts, R F; Murphy, B R

    1984-03-31

    The efficacy of live attenuated cold-adapted (ca) reassortant influenza virus vaccine against experimental challenge with homologous wild-type virus 5 to 8 weeks after vaccination was compared with that of licensed inactivated vaccine in 81 seronegative (haemagglutination-inhibition antibody titre less than or equal to 1:8) college students. At a dose of 10(7.5) 50% tissue culture infectious dose (TCID50) (70 HID50, human 50% infectious doses) the live virus vaccine, given intranasally, completely protected against illness caused by wild-type virus, whereas the inactivated vaccine, administered intramuscularly, provided 72% protection. Wild-type virus was recovered from only 13% of live virus vaccinees (10(7.5) TCID50 dose of ca virus) compared with 63% of inactivated virus vaccinees and the few infected live virus vaccinees shed 1000 times less wild-type virus than did infected inactivated virus vaccinees or unvaccinated controls. This striking reduction in virus shedding suggests that influenza transmission may be more efficiently interrupted with live than with inactivated virus vaccination.

  18. A case of unusual septic knee arthritis with Brucella abortus after arthroscopic meniscus surgery.

    PubMed

    Lee, Keun Hwa; Kang, Hyunseong; Kim, Taejung; Choi, Sungwook

    2016-01-01

    We present a 51-year-old male patient with Brucella abortus septic arthritis in the right knee following arthroscopic meniscus surgery. He had eaten a traditional dish of raw minced cattle conceptus (bovine fetus) that was prepared after the cow was slaughtered. Despite treatment with empirical antibiotics and debridement of the postoperative surgical wound, the infection persisted without improvement. Polymerase chain reaction sequencing identified Brucella abortus from tissue samples obtained from the patient. After confirmation of the diagnosis of brucellar infection, antibiotics were replaced with doxycycline and rifampin, which were used for 4 months. In patients with a non-specific arthralgia who eat raw meat or live close to animals, it is important to consider the possibility of septic arthritis due to infection with Brucella spp.

  19. A Novel Live Pichinde Virus-Based Vaccine Vector Induces Enhanced Humoral and Cellular Immunity after a Booster Dose

    PubMed Central

    Dhanwani, Rekha; Zhou, Yanqin; Huang, Qinfeng; Verma, Vikram; Dileepan, Mythili; Ly, Hinh

    2015-01-01

    ABSTRACT Pichinde virus (PICV) is a bisegmented enveloped RNA virus that targets macrophages and dendritic cells (DCs) early in infection and induces strong innate and adaptive immunity in mice. We have developed a reverse genetics system to produce live recombinant PICV (strain P18) with a trisegmented RNA genome (rP18tri), which encodes all four PICV gene products and as many as two foreign genes. We have engineered the vector to express the green fluorescent protein (GFP) reporter gene (abbreviated as G in virus designations) and either the hemagglutination (HA [H]) or the nucleoprotein (NP [P]) gene of the influenza A/PR8 virus. The trisegmented viruses rP18tri-G/H and rP18tri-G/P showed slightly reduced growth in vitro and expressed HA and NP, respectively. Mice immunized with rP18tri-G/H were completely protected against lethal influenza virus challenge even 120 days after immunization. These rP18tri-based vectors could efficiently induce both neutralizing antibodies and antigen-specific T cell responses via different immunization routes. Interestingly, the immune responses were significantly increased upon a booster dose and remained at high levels even after three booster doses. In summary, we have developed a novel PICV-based live vaccine vector that can express foreign antigens to induce strong humoral and cell-mediated immunity and is ideal for a prime-and-boost vaccination strategy. IMPORTANCE We have developed a novel Pichinde virus (PICV)-based live viral vector, rP18tri, that packages three RNA segments and encodes as many as two foreign genes. Using the influenza virus HA and NP genes as model antigens, we show that this rP18tri vector can induce strong humoral and cellular immunity via different immunization routes and can lead to protection in mice. Interestingly, a booster dose further enhances the immune responses, a feature that distinguishes this from other known live viral vectors. In summary, our study demonstrates a unique feature of this

  20. Microneedle Array Design Determines the Induction of Protective Memory CD8+ T Cell Responses Induced by a Recombinant Live Malaria Vaccine in Mice

    PubMed Central

    Carey, John B.; Pearson, Frances E.; Vrdoljak, Anto; McGrath, Marie G.; Crean, Abina M.; Walsh, Patrick T.; Doody, Timothy; O'Mahony, Conor; Hill, Adrian V. S.; Moore, Anne C.

    2011-01-01

    Background Vaccine delivery into the skin has received renewed interest due to ease of access to the immune system and microvasculature, however the stratum corneum (SC), must be breached for successful vaccination. This has been achieved by removing the SC by abrasion or scarification or by delivering the vaccine intradermally (ID) with traditional needle-and-syringes or with long microneedle devices. Microneedle patch-based transdermal vaccine studies have predominantly focused on antibody induction by inactivated or subunit vaccines. Here, our principal aim is to determine if the design of a microneedle patch affects the CD8+ T cell responses to a malaria antigen induced by a live vaccine. Methodology and Findings Recombinant modified vaccinia virus Ankara (MVA) expressing a malaria antigen was percutaneously administered to mice using a range of silicon microneedle patches, termed ImmuPatch, that differed in microneedle height, density, patch area and total pore volume. We demonstrate that microneedle arrays that have small total pore volumes induce a significantly greater proportion of central memory T cells that vigorously expand to secondary immunization. Microneedle-mediated vaccine priming induced significantly greater T cell immunity post-boost and equivalent protection against malaria challenge compared to ID vaccination. Notably, unlike ID administration, ImmuPatch-mediated vaccination did not induce inflammatory responses at the site of immunization or in draining lymph nodes. Conclusions/Significance This study demonstrates that the design of microneedle patches significantly influences the magnitude and memory of vaccine-induced CD8+ T cell responses and can be optimised for the induction of desired immune responses. Furthermore, ImmuPatch-mediated delivery may be of benefit to reducing unwanted vaccine reactogenicity. In addition to the advantages of low cost and lack of pain, the development of optimised microneedle array designs for the induction

  1. Live RB51 vaccine lyophilized hydrogel formulations with increased shelf life for practical ballistic delivery

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Ballistic delivery capability is essential to delivering vaccines and other therapeutics effectively to both livestock and wildlife in many global scenarios. Here, lyophilized poly(ethylene glycol) (PEG)-glycolide dimethacrylate crosslinked but degradable hydrogels were assessed as payload vehicles ...

  2. DENGUE VACCINES.

    PubMed

    Thisyakorn, Usa; Thisyakorn, Chule

    2015