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Sample records for selected vaccine strains

  1. Genetic and antigenic characterization of serotype O FMD viruses from East Africa for the selection of suitable vaccine strain.

    Science.gov (United States)

    Lloyd-Jones, Katie; Mahapatra, Mana; Upadhyaya, Sasmita; Paton, David J; Babu, Aravindh; Hutchings, Geoff; Parida, Satya

    2017-12-14

    Foot-and-mouth disease (FMD) is endemic in Eastern Africa with circulation of multiple serotypes of the virus in the region. Most of the outbreaks are caused by serotype O followed by serotype A. The lack of concerted FMD control programmes in Africa has provided little incentive for vaccine producers to select vaccines that are tailored to circulating regional isolates creating further negative feedback to deter the introduction of vaccine-based control schemes. In this study a total of 80 serotype O FMD viruses (FMDV) isolated from 1993 to 2012 from East and North Africa were characterized by virus neutralisation tests using bovine antisera to three existing (O/KEN/77/78, O/Manisa and O/PanAsia-2) and three putative (O/EA/2002, O/EA/2009 and O/EA/2010) vaccine strains and by capsid sequencing. Genetically, these viruses were grouped as either of East African origin with subdivision into four topotypes (EA-1, 2, 3 and 4) or of Middle-East South Asian (ME-SA) topotype. The ME-SA topotype viruses were mainly detected in Egypt and Libya reflecting the trade links with the Middle East countries. There was good serological cross-reactivity between the vaccine strains and most of the field isolates analysed, indicating that vaccine selection should not be a major constraint for control of serotype O FMD by vaccination, and that both local and internationally available commercial vaccines could be used. The O/KEN/77/78 vaccine, commonly used in the region, exhibited comparatively lower percent in vitro match against the predominant topotypes (EA-2 and EA-3) circulating in the region whereas O/PanAsia-2 and O/Manisa vaccines revealed broader protection against East African serotype O viruses, even though they genetically belong to the ME-SA topotype. Copyright © 2017 The Author(s). Published by Elsevier Ltd.. All rights reserved.

  2. Biohazard Analysis of Select Biodefense Vaccine Candidates - Venezuelan Equine Encephalitis Virus Strain 3526 and Francisella Tularensis LVS

    International Nuclear Information System (INIS)

    Rao, V.

    2007-01-01

    Biohazard assessment of biodefense vaccine candidates forms the basis for a facility- and activity-specific risk assessment performed to determine the biosafety levels and general safety standards required for biological product development. As a part of our support to the US biodefense vaccine development program, we perform a systematic biohazard assessment of potential vaccine candidates with the primary objective to, (a) Identify and characterize hazard elements associated with the wild type and vaccine strains, (b) Provide biohazard information on the etiologic agent (vaccine candidate) to assess Phase 1 clinical trial facility sites, (c) Provide a baseline to conduct an agent and facility-specific risk assessment at clinical trial facilities interested in performing phase 1 clinical trial, (d) Provide comparative hazard profiles of the vaccine candidates wit MSDS for wild-type to identify and establish appropriate protective biosafety levels, and (e) Support determination of a hazard level to select personal protective equipment as required under the OSHA guidelines. This paper will describe the biohazard analysis of two vaccine candidates, Venezuelan Equine Encephalitis Virus Strain 3526 and Francisella tularensis LVS, a viral and bacterial agent, respectively. As part of the biohazard assessment we preformed a thorough review of published literature on medical pathology, epidemiology, pre-clinical investigational studies, and environmental data on the etiologic agent subtypes and the vaccine candidates. Using standard analytical procedures, the data were then analyzed relative to two intrinsic hazard parameters-health hazard and environmental hazard. Using a weight-of-evidence (WOE) approach, the potential hazards of etiologic agent wild subtypes and vaccine candidates were ranked under three main categories: Public Health Hazard, Environmental Hazard, and Overall Hazard. A WOE scoring system allows for both a determination of the intrinsic hazard of each

  3. Biohazard Analysis of Select Biodefense Vaccine Candidates - Venezuelan Equine Encephalitis Virus Strain 3526 and Francisella Tularensis LVS

    Energy Technology Data Exchange (ETDEWEB)

    Rao, V [National Security Programs, Computer Science Corporation, Alexandria (United States)

    2007-07-01

    Biohazard assessment of biodefense vaccine candidates forms the basis for a facility- and activity-specific risk assessment performed to determine the biosafety levels and general safety standards required for biological product development. As a part of our support to the US biodefense vaccine development program, we perform a systematic biohazard assessment of potential vaccine candidates with the primary objective to, (a) Identify and characterize hazard elements associated with the wild type and vaccine strains, (b) Provide biohazard information on the etiologic agent (vaccine candidate) to assess Phase 1 clinical trial facility sites, (c) Provide a baseline to conduct an agent and facility-specific risk assessment at clinical trial facilities interested in performing phase 1 clinical trial, (d) Provide comparative hazard profiles of the vaccine candidates wit MSDS for wild-type to identify and establish appropriate protective biosafety levels, and (e) Support determination of a hazard level to select personal protective equipment as required under the OSHA guidelines. This paper will describe the biohazard analysis of two vaccine candidates, Venezuelan Equine Encephalitis Virus Strain 3526 and Francisella tularensis LVS, a viral and bacterial agent, respectively. As part of the biohazard assessment we preformed a thorough review of published literature on medical pathology, epidemiology, pre-clinical investigational studies, and environmental data on the etiologic agent subtypes and the vaccine candidates. Using standard analytical procedures, the data were then analyzed relative to two intrinsic hazard parameters-health hazard and environmental hazard. Using a weight-of-evidence (WOE) approach, the potential hazards of etiologic agent wild subtypes and vaccine candidates were ranked under three main categories: Public Health Hazard, Environmental Hazard, and Overall Hazard. A WOE scoring system allows for both a determination of the intrinsic hazard of each

  4. vaccination with newcastle disease vaccines strain i2 and lasota

    African Journals Online (AJOL)

    UP Employee

    mash feed as vaccine carriers was conducted. Newcastle disease vaccine strain I2 and. NDV La Sota vaccines provided protection to commercial and local chickens vaccinated through i/o, i/m or dw. No significant difference (P≤0.05) was observed in the antibody titre of commercial or local chickens vaccinated with either ...

  5. Mumps vaccine virus strains and aseptic meningitis.

    Science.gov (United States)

    Bonnet, Marie-Claude; Dutta, Anil; Weinberger, Clement; Plotkin, Stanley A

    2006-11-30

    Mumps immunization can easily be included in national schedules, particularly if combined with measles or measles and rubella vaccines, but debate continues concerning the relative safety of various licensed mumps vaccine strains. The opportunities for control of mumps are also being affected by differences in the cost of the vaccines prepared with different strains of mumps virus. The present report evaluates available data on the association of the Urabe and other strains of mumps vaccine with the occurrence of aseptic meningitis. We also review the comparative immunogenicity and efficacies of the most widely used mumps vaccines in controlled clinical trials and field evaluations, and briefly examine relative cost as it relates to the implementation of national immunization programs. We conclude that extensive experience with the most widely used mumps vaccine strains in many countries has shown that the risk-benefit ratio of live mumps vaccines is highly favourable for vaccination, despite the occasional occurence of aseptic meningitis.

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

    Science.gov (United States)

    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...

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

    Science.gov (United States)

    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. Copyright © 2016 Elsevier B.V. All rights reserved.

  8. Genome sequencing and analysis of BCG vaccine strains.

    Directory of Open Access Journals (Sweden)

    Wen Zhang

    Full Text Available BACKGROUND: Although the Bacillus Calmette-Guérin (BCG vaccine against tuberculosis (TB has been available for more than 75 years, one third of the world's population is still infected with Mycobacterium tuberculosis and approximately 2 million people die of TB every year. To reduce this immense TB burden, a clearer understanding of the functional genes underlying the action of BCG and the development of new vaccines are urgently needed. METHODS AND FINDINGS: Comparative genomic analysis of 19 M. tuberculosis complex strains showed that BCG strains underwent repeated human manipulation, had higher region of deletion rates than those of natural M. tuberculosis strains, and lost several essential components such as T-cell epitopes. A total of 188 BCG strain T-cell epitopes were lost to various degrees. The non-virulent BCG Tokyo strain, which has the largest number of T-cell epitopes (359, lost 124. Here we propose that BCG strain protection variability results from different epitopes. This study is the first to present BCG as a model organism for genetics research. BCG strains have a very well-documented history and now detailed genome information. Genome comparison revealed the selection process of BCG strains under human manipulation (1908-1966. CONCLUSIONS: Our results revealed the cause of BCG vaccine strain protection variability at the genome level and supported the hypothesis that the restoration of lost BCG Tokyo epitopes is a useful future vaccine development strategy. Furthermore, these detailed BCG vaccine genome investigation results will be useful in microbial genetics, microbial engineering and other research fields.

  9. Selection of vaccine strains for serotype O foot-and-mouth disease viruses (2007-2012) circulating in Southeast Asia, East Asia and Far East.

    Science.gov (United States)

    Mahapatra, Mana; Upadhyaya, Sasmita; Aviso, Sharie; Babu, Aravindh; Hutchings, Geoff; Parida, Satya

    2017-12-18

    Foot-and-mouth disease (FMD) is endemic in Southeast Asia (SEA) and East Asia with circulation of multiple serotypes and multiple genotypes within each serotype of the virus. Although countries like Japan and South Korea in the Far East were free of FMD, in 2010 FMD serotype O (O/Mya-98) outbreaks were recorded and since then South Korea has experienced several FMD outbreaks despite regular vaccination. In this study a total of 85 serotype O FMD viruses (FMDV) isolated from 2007 to 2012 from SEA, East Asia and Far East were characterized by virus neutralisation tests using antisera to four existing (O/HKN/6/83, O/IND/R2/75, O/SKR/2010 and O/PanAsia-2) and one putative (O/MYA/2009) vaccine strains, and by full capsid sequencing. Serological studies revealed broad cross-reactivity with the vaccine strains; O/PanAsia-2 exhibited a good match with 95.3%, O/HKN/6/83 with 91.8%, O/IND/R2/75 with 80%, and the putative strain O/MYA/2009 with 89.4% isolates employed in this study. Similarly O/PanAsia-2 and O/IND/R2/75 vaccines showed a good match with all eight viruses belonging to O-Ind-2001d sublineage whereas the vaccines of O/Mya-98 lineage, O/MYA/2009 and O/SKR/2010 exhibited the lowest match indicating their unsuitability to protect infections from O-Ind-2001d viruses. A Bayesian analysis of the capsid sequence data indicated these circulating viruses (n = 85) to be of either SEA or Middle East-South Asian (ME-SA) topotype. The ME-SA topotype viruses were mainly detected in Lao PDR, Vietnam, Myanmar and Thailand reflecting the trade links with the Indian subcontinent, and also within the SEA countries. Implications of these results in the context of FMD control in SEA and East Asian countries are discussed. Copyright © 2017 The Author(s). Published by Elsevier Ltd.. All rights reserved.

  10. Structural changes in γ-irradiated Brucella strain chemical vaccine

    International Nuclear Information System (INIS)

    Dranovskaya, E.A.; Kulikov, V.I.

    1986-01-01

    It was shown that γ-irradiation of Brucella strain chemical vaccine stimulated phospholipid peroxidation therein: the content of extractable total phospholipids in the exposed vaccine decreased mainly due to diminution of phosphatidynatidylcholines and phosphatidylethanolamines. A relative content of high- and low-molecular weight protein componets increase in the γ-irradiated vaccine

  11. Frequency of adverse events after vaccination with different vaccinia strains.

    Directory of Open Access Journals (Sweden)

    Mirjam Kretzschmar

    2006-08-01

    Full Text Available BACKGROUND: Large quantities of smallpox vaccine have been stockpiled to protect entire nations against a possible reintroduction of smallpox. Planning for an appropriate use of these stockpiled vaccines in response to a smallpox outbreak requires a rational assessment of the risks of vaccination-related adverse events, compared to the risk of contracting an infection. Although considerable effort has been made to understand the dynamics of smallpox transmission in modern societies, little attention has been paid to estimating the frequency of adverse events due to smallpox vaccination. Studies exploring the consequences of smallpox vaccination strategies have commonly used a frequency of approximately one death per million vaccinations, which is based on a study of vaccination with the New York City Board of Health (NYCBH strain of vaccinia virus. However, a multitude of historical studies of smallpox vaccination with other vaccinia strains suggest that there are strain-related differences in the frequency of adverse events after vaccination. Because many countries have stockpiled vaccine based on the Lister strain of vaccinia virus, a quantitative evaluation of the adverse effects of such vaccines is essential for emergency response planning. We conducted a systematic review and statistical analysis of historical data concerning vaccination against smallpox with different strains of vaccinia virus. METHODS AND FINDINGS: We analyzed historical vaccination data extracted from the literature. We extracted data on the frequency of postvaccinal encephalitis and death with respect to vaccinia strain and age of vaccinees. Using a hierarchical Bayesian approach for meta-analysis, we estimated the expected frequencies of postvaccinal encephalitis and death with respect to age at vaccination for smallpox vaccines based on the NYCBH and Lister vaccinia strains. We found large heterogeneity between findings from different studies and a time-period effect

  12. Are vaccine strain, type or administration protocol risk factors for canine parvovirus vaccine failure?

    Science.gov (United States)

    Altman, K D; Kelman, M; Ward, M P

    2017-10-01

    Canine parvovirus (CPV) is a highly contagious and worldwide cause of serious and often fatal disease in dogs, despite the widespread availability of vaccines. Which vaccine-related factors are associated with vaccination failure is largely unknown, and there are no reports from Australia. In this study - the first national population-level CPV study of its kind ever conducted - we analysed data on 594 cases of apparent CPV vaccination failure reported from an Australian national surveillance system to determine whether vaccine strain, type or administration protocol are risk factors for vaccination failures. The strain of CPV used in vaccine manufacture was not significantly associated with vaccination failure in clinical practice. The vaccine type (killed versus attenuated vaccine) for puppies diagnosed with CPV was associated with a lower mean age at time of vaccination (P=0.0495). The age at administration of the last CPV vaccination a puppy received prior to presenting with disease was a significant (P=0.0334) risk factor for vaccination failure, irrespective of whether the vaccine was marketed for a 10-week or 12-week or greater vaccination finish protocol. There was also a strong negative correlation between age at last vaccination prior to disease and vaccination failure (Pparvovirus vaccines, especially in outbreak situations. The large number of cases identified in this study confirms that CPV vaccination failure is occurring in Australia. Veterinarians should consider CPV as a differential diagnosis in cases with appropriate clinical presentation, regardless of the reported vaccination status of the dog. Copyright © 2017 Elsevier B.V. All rights reserved.

  13. Rotavirus vaccine strain transmission by vaccinated infants in the foster home.

    Science.gov (United States)

    Miura, Hiroki; Kawamura, Yoshiki; Sugata, Ken; Koshiyama, Nozomi; Yoshikawa, Akiko; Komoto, Satoshi; Taniguchi, Koki; Ihira, Masaru; Yoshikawa, Tetsushi

    2017-01-01

    Previous studies have demonstrated the transmission of rotavirus vaccine strains from vaccinated children to nonvaccinated siblings. We sought to fully elucidate the safety of rotavirus (RV) vaccination in closed contact circumstance, such as the foster home for future assessment of the vaccine safety in an neonatal intensive care unit. Stool samples were collected from 4 RV vaccinated (160 samples) and 23 unvaccinated (766 samples) infants. RV viral RNA loads were measured using real-time reverse transcription polymerase chain reaction (RT-PCR). RV vaccine strain RNA was persistently detected in stool samples collected from the four vaccine recipients and one unvaccinated infant, but not in the stool samples collected from the 22 other unvaccinated infants. The unvaccinated infant who tested positive for the RV vaccine strain was vaccinated prior to enrollment in this study. The quantitative real-time RT-PCR data revealed a peak viral RNA load 1 week after vaccination followed by a gradual decrease. The current study suggests that RV vaccination may be safe in a close contact environment because there was limited transmission from RV vaccinated to unvaccinated infants. J. Med. Virol. 89:79-84, 2017. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

  14. Genetic characterization of L-Zagreb mumps vaccine strain.

    Science.gov (United States)

    Ivancic, Jelena; Gulija, Tanja Kosutic; Forcic, Dubravko; Baricevic, Marijana; Jug, Renata; Mesko-Prejac, Majda; Mazuran, Renata

    2005-04-01

    Eleven mumps vaccine strains, all containing live attenuated virus, have been used throughout the world. Although L-Zagreb mumps vaccine has been licensed since 1972, only its partial nucleotide sequence was previously determined (accession numbers , and ). Therefore, we sequenced the entire genome of L-Zagreb vaccine strain (Institute of Immunology Inc., Zagreb, Croatia). In order to investigate the genetic stability of the vaccine, sequences of both L-Zagreb master seed and currently produced vaccine batch were determined and no difference between them was observed. A phylogenetic analysis based on SH gene sequence has shown that L-Zagreb strain does not belong to any of established mumps genotypes and that it is most similar to old, laboratory preserved European strains (1950s-1970s). L-Zagreb nucleotide and deduced protein sequences were compared with other mumps virus sequences obtained from the GenBank. Emphasis was put on functionally important protein regions and known antigenic epitopes. The extensive comparisons of nucleotide and deduced protein sequences between L-Zagreb vaccine strain and other previously determined mumps virus sequences have shown that while the functional regions of HN, V, and L proteins are well conserved among various mumps strains, there can be a substantial amino acid difference in antigenic epitopes of all proteins and in functional regions of F protein. No molecular pattern was identified that can be used as a distinction marker between virulent and attenuated strains.

  15. Comparison of the live attenuated yellow fever vaccine 17D-204 strain to its virulent parental strain Asibi by deep sequencing.

    Science.gov (United States)

    Beck, Andrew; Tesh, Robert B; Wood, Thomas G; Widen, Steven G; Ryman, Kate D; Barrett, Alan D T

    2014-02-01

    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. 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. 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. 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.

  16. Phylogenetic analysis of Hungarian goose parvovirus isolates and vaccine strains.

    Science.gov (United States)

    Tatár-Kis, Tímea; Mató, Tamás; Markos, Béla; Palya, Vilmos

    2004-08-01

    Polymerase chain reaction and sequencing were used to analyse goose parvovirus field isolates and vaccine strains. Two fragments of the genome were amplified. Fragment "A" represents a region of VP3 gene, while fragment "B" represents a region upstream of the VP3 gene, encompassing part of the VP1 gene. In the region of fragment "A" the deduced amino acid sequence of the strains was identical, therefore differentiation among strains could be done only at the nucleotide level, which resulted in the formation of three groups: Hungarian, West-European and Asian strains. In the region of fragment "B", separation of groups could be done by both nucleotide and deduced amino acid sequence level. The nucleotide sequences resulted in the same groups as for fragment "A" but with a different clustering pattern among the Hungarian strains. Within the "Hungarian" group most of the recent field isolates fell into one cluster, very closely related or identical to each other, indicating a very slow evolutionary change. The attenuated strains and field isolates from 1979/80 formed a separate cluster. When vaccine strains and field isolates were compared, two specific amino acid differences were found that can be considered as possible markers for vaccinal strains. Sequence analysis of fragment "B" seems to be a suitable method for differentiation of attenuated vaccine strains from virulent strains. Copyright 2004 Houghton Trust Ltd

  17. Genetic heterogeneity of L-Zagreb mumps virus vaccine strain

    Directory of Open Access Journals (Sweden)

    Mateljak-Lukacevic Sanja

    2008-07-01

    Full Text Available Abstract Background The most often used mumps vaccine strains Jeryl Lynn (JL, RIT4385, Urabe-AM9, L-Zagreb and L-3 differ in immunogenicity and reactogenicity. Previous analyses showed that JL, Urabe-AM9 and L-3 are genetically heterogeneous. Results We identified the heterogeneity of L-Zagreb throughout the entire genome. Two major variants were defined: variant A being identical to the consensus sequence of viral seeds and vaccine(s and variant B which differs from variant A in three nucleotide positions. The difference between viral variants in L-Zagreb strain is insufficient for distinct viral strains to be defined. We demonstrated that proportion of variants in L-Zagreb viral population depends on cell substrate used for viral replication in vitro and in vivo. Conclusion L-Zagreb strain should be considered as a single strain composed of at least two variant viral genomes.

  18. Genetic heterogeneity of L-Zagreb mumps virus vaccine strain

    Science.gov (United States)

    Kosutic-Gulija, Tanja; Forcic, Dubravko; Šantak, Maja; Ramljak, Ana; Mateljak-Lukacevic, Sanja; Mazuran, Renata

    2008-01-01

    Background The most often used mumps vaccine strains Jeryl Lynn (JL), RIT4385, Urabe-AM9, L-Zagreb and L-3 differ in immunogenicity and reactogenicity. Previous analyses showed that JL, Urabe-AM9 and L-3 are genetically heterogeneous. Results We identified the heterogeneity of L-Zagreb throughout the entire genome. Two major variants were defined: variant A being identical to the consensus sequence of viral seeds and vaccine(s) and variant B which differs from variant A in three nucleotide positions. The difference between viral variants in L-Zagreb strain is insufficient for distinct viral strains to be defined. We demonstrated that proportion of variants in L-Zagreb viral population depends on cell substrate used for viral replication in vitro and in vivo. Conclusion L-Zagreb strain should be considered as a single strain composed of at least two variant viral genomes. PMID:18616793

  19. Genetic heterogeneity of L-Zagreb mumps virus vaccine strain.

    Science.gov (United States)

    Kosutic-Gulija, Tanja; Forcic, Dubravko; Santak, Maja; Ramljak, Ana; Mateljak-Lukacevic, Sanja; Mazuran, Renata

    2008-07-10

    The most often used mumps vaccine strains Jeryl Lynn (JL), RIT4385, Urabe-AM9, L-Zagreb and L-3 differ in immunogenicity and reactogenicity. Previous analyses showed that JL, Urabe-AM9 and L-3 are genetically heterogeneous. We identified the heterogeneity of L-Zagreb throughout the entire genome. Two major variants were defined: variant A being identical to the consensus sequence of viral seeds and vaccine(s) and variant B which differs from variant A in three nucleotide positions. The difference between viral variants in L-Zagreb strain is insufficient for distinct viral strains to be defined. We demonstrated that proportion of variants in L-Zagreb viral population depends on cell substrate used for viral replication in vitro and in vivo. L-Zagreb strain should be considered as a single strain composed of at least two variant viral genomes.

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

    Science.gov (United States)

    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.

  1. [Genetic recombination in vaccine poliovirus: comparative study in strains excreted in course of vaccination by oral poliovirus vaccine and circulating strains].

    Science.gov (United States)

    Haddad-Boubaker, S; Ould-Mohamed-Abdallah, M V; Ben-Yahia, A; Triki, H

    2010-12-01

    Recombination is one of the major mechanisms of evolution in poliovirus. In this work, recombination was assessed in children during vaccination with OPV and among circulating vaccine strains isolated in Tunisia during the last 15 years in order to identify a possible role of recombination in the response to the vaccine or the acquisition of an increased transmissibility. This study included 250 poliovirus isolates: 137 vaccine isolates, excreted by children during primary vaccination with OPV and 113 isolates obtained from acute flaccid paralytic (AFP) cases and healthy contacts. Recombination was first assessed using a double PCR-RFLP, and sequencing. Nineteen per cent of recombinant strains were identified: 20% of strains excreted by vaccinees among 18% of circulating strains. The proportion of recombinant in isolates of serotype1 was very low in the two groups while the proportions of recombinants in serotypes 2 and 3 were different. In vaccinees, the frequency of recombinants in serotype3 decreased during the course of vaccination: 54% after the first dose, 32% after the second and 14% after the third dose. These results suggest that recombination enhances the ability of serotype3 vaccine strains to induce an immune response. Apart from recent vaccination, it may contribute to a more effective transmissibility of vaccine strains among human population. Copyright © 2009 Elsevier Masson SAS. All rights reserved.

  2. Comparative Proteomic Profiling of Mycobacterium bovis and BCG Vaccine Strains

    KAUST Repository

    Gao, Ge

    2013-09-01

    BCG is the only licensed human vaccine currently available against TB. Derived from a virulent strain of M. bovis, the vaccine was thought to have struck a balance between reduced virulence and preserved immunogenicity. Nowadays, BCG vaccine strains used in different countries and vaccination programs show clear variations in their genomes and immune protective properties. The aim of this study was to characterize the proteomic profile on Mycobacterium bovis and five BCG strains Pasteur, Tokyo, Danish, Phipps and Birkhaug by Tandem Mass Tag® (TMT®)-labeling quantitative proteomic approach. In total, 420 proteins were identified and 377 of them were quantitated for their relative abundance. We reported the number and relationship of differential expressed proteins in BCG strains compared to M. bovis and investigated their functions by bioinformatics analysis. Several interesting up-regulated and down-regulated protein targets were found. The identified proteins and their quantitative expression profiles provide a basis for further understanding of the cellular biology of M. bovis and BCG vaccine strains, and hopefully would assist in the design of better anti-TB vaccine and drugs.

  3. Assessment of a strain 19 brucellosis vaccination program in elk

    Science.gov (United States)

    Maichak, Eric J.; Scurlock, Brandon M.; Cross, Paul C.; Rogerson, Jared D.; Edwards, William H.; Wise, Benjamin; Smith, Scott G.; Kreeger, Terry J.

    2017-01-01

    Zoonotic diseases in wildlife present substantial challenges and risks to host populations, susceptible domestic livestock populations, and affected stakeholders. Brucellosis, a disease caused by the bacterium Brucella abortus, is endemic among elk (Cervus canadensis) attending winter feedgrounds and adjacent areas of western Wyoming, USA. To minimize transmission of brucellosis from elk to elk and elk to livestock, managers initiated a B. abortus strain 19 ballistic vaccination program in 1985. We used brucellosis prevalence (1971–2015) and reproductive outcome (2006–2015) data collected from female elk attending feedgrounds to assess efficacy of the strain 19 program while controlling for potentially confounding factors such as site and age. From our generalized linear models, we found that seroprevalence of brucellosis was 1) not lower following inception of vaccination; 2) not inversely associated with proportion of juveniles vaccinated over time; 3) not inversely associated with additional yearlings and adults vaccinated over time; and 4) associated more with feeding end-date than proportion of juveniles vaccinated. Using vaginal implant transmitters in adult females that were seropositive for brucellosis, we found little effect of vaccination coverage at reducing reproductive failures (i.e., abortion or stillbirth). Because we found limited support for efficacy of the strain 19 program, we support research to develop an oral vaccine and suggest that continuing other spatio-temporal management actions will be most effective to minimize transmission of brucellosis and reduce dependency of elk on supplemental winter feeding.

  4. Low Dose Vaccination with Attenuated Francisella tularensis Strain SchuS4 Mutants Protects against Tularemia Independent of the Route of Vaccination

    Science.gov (United States)

    Rockx-Brouwer, Dedeke; Chong, Audrey; Wehrly, Tara D.; Child, Robert; Crane, Deborah D.

    2012-01-01

    Tularemia, caused by the Gram-negative bacterium Francisella tularensis, is a severe, sometimes fatal disease. Interest in tularemia has increased over the last decade due to its history as a biological weapon. In particular, development of novel vaccines directed at protecting against pneumonic tularemia has been an important goal. Previous work has demonstrated that, when delivered at very high inoculums, administration of live, highly attenuated strains of virulent F. tularensis can protect against tularemia. However, lower vaccinating inoculums did not offer similar immunity. One concern of using live vaccines is that the host may develop mild tularemia in response to infection and use of high inoculums may contribute to this issue. Thus, generation of a live vaccine that can efficiently protect against tularemia when delivered in low numbers, e.g. tularemia when delivered at concentrations of approximately 50 or fewer bacteria. Attenuated strains for use as vaccines were selected by their inability to efficiently replicate in macrophages in vitro and impaired replication and dissemination in vivo. Although all strains were defective for replication in vitro within macrophages, protective efficacy of each attenuated mutant was correlated with their ability to modestly replicate and disseminate in the host. Finally, we demonstrate the parenteral vaccination with these strains offered superior protection against pneumonic tularemia than intranasal vaccination. Together our data provides proof of principle that low dose attenuated vaccines may be a viable goal in development of novel vaccines directed against tularemia. PMID:22662210

  5. Brunenders: a partially attenuated historic poliovirus type I vaccine strain.

    Science.gov (United States)

    Sanders, Barbara P; Liu, Ying; Brandjes, Alies; van Hoek, Vladimir; de Los Rios Oakes, Isabel; Lewis, John; Wimmer, Eckard; Custers, Jerome H H V; Schuitemaker, Hanneke; Cello, Jeronimo; Edo-Matas, Diana

    2015-09-01

    Brunenders, a type I poliovirus (PV) strain, was developed in 1952 by J. F. Enders and colleagues through serial in vitro passaging of the parental Brunhilde strain, and was reported to display partial neuroattenuation in monkeys. This phenotype of attenuation encouraged two vaccine manufacturers to adopt Brunenders as the type I component for their inactivated poliovirus vaccines (IPVs) in the 1950s, although today no licensed IPV vaccine contains Brunenders. Here we confirmed, in a transgenic mouse model, the report of Enders on the reduced neurovirulence of Brunenders. Although dramatically neuroattenuated relative to WT PV strains, Brunenders remains more virulent than the attenuated oral vaccine strain, Sabin 1. Importantly, the neuroattenuation of Brunenders does not affect in vitro growth kinetics and in vitro antigenicity, which were similar to those of Mahoney, the conventional type I IPV vaccine strain. We showed, by full nucleotide sequencing, that Brunhilde and Brunenders differ at 31 nucleotides, eight of which lead to amino acid changes, all located in the capsid. Upon exchanging the Brunenders capsid sequence with that of the Mahoney capsid, WT neurovirulence was regained in vivo, suggesting a role for the capsid mutations in Brunenders attenuation. To date, as polio eradication draws closer, the switch to using attenuated strains for IPV is actively being pursued. Brunenders preceded this novel strategy as a partially attenuated IPV strain, accompanied by decades of successful use in the field. Providing data on the attenuation of Brunenders may be of value in the further construction of attenuated PV strains to support the grand pursuit of the global eradication of poliomyelitis.

  6. Molecular typing of Brucella melitensis endemic strains and differentiation from the vaccine strain Rev-1.

    Science.gov (United States)

    Noutsios, Georgios T; Papi, Rigini M; Ekateriniadou, Loukia V; Minas, Anastasios; Kyriakidis, Dimitrios A

    2012-03-01

    In the present study forty-four Greek endemic strains of Br. melitensis and three reference strains were genotyped by Multi locus Variable Number Tandem Repeat (ML-VNTR) analysis based on an eight-base pair tandem repeat sequence that was revealed in eight loci of Br. melitensis genome. The forty-four strains were discriminated from the vaccine strain Rev-1 by Restriction Fragment Length Polymorphism (RFLP) and Denaturant Gradient Gel Electrophoresis (DGGE). The ML-VNTR analysis revealed that endemic, reference and vaccine strains are genetically closely related, while most of the loci tested (1, 2, 4, 5 and 7) are highly polymorphic with Hunter-Gaston Genetic Diversity Index (HGDI) values in the range of 0.939 to 0.775. Analysis of ML-VNTRs loci stability through in vitro passages proved that loci 1 and 5 are non stable. Therefore, vaccine strain can be discriminated from endemic strains by allele's clusters of loci 2, 4, 6 and 7. RFLP and DGGE were also employed to analyse omp2 gene and reveled different patterns among Rev-1 and endemic strains. In RFLP, Rev-1 revealed three fragments (282, 238 and 44 bp), while endemic strains two fragments (238 and 44 bp). As for DGGE, the electrophoretic mobility of Rev-1 is different from the endemic strains due to heterologous binding of DNA chains of omp2a and omp2b gene. Overall, our data show clearly that it is feasible to genotype endemic strains of Br. melitensis and differentiate them from vaccine strain Rev-1 with ML-VNTR, RFLP and DGGE techniques. These tools can be used for conventional investigations in brucellosis outbreaks.

  7. Mumps Hoshino and Torii vaccine strains were distinguished from circulating wild strains.

    Science.gov (United States)

    Sawada, Akihito; Yamaji, Yoshiaki; Nakayama, Tetsuo

    2013-06-01

    Aseptic meningitis and acute parotitis have been observed after mumps vaccination. Mumps outbreaks have been reported in Japan because of low vaccine coverage, and molecular differentiation is required to determine whether these cases are vaccine associated. RT-nested PCR was performed in the small hydrophobic gene region, and viruses were differentiated by restriction fragment length polymorphism assay. A total of 584 nucleotides were amplified. The PCR product of the Hoshino strain was cut into two fragments (313 and 271 nucleotides) by MfeI; that of the Torii strain was digested with EcoT22I, resulting in 332- and 252-nucleotide fragments. Both strains were genotype B and had an XbaI site, resulting in two fragments: 299 and 285 nucleotides. Current circulating wild types were cut only by XbaI or MfeI. However, the MfeI site of the wild types was different from that of the Hoshino strain, resulting in 451- and 133-nucleotide fragments. Using three restriction enzymes, two mumps vaccine strains were distinguished from wild types, and this separation was applied to the identification of vaccine-related adverse events.

  8. The risk of aseptic meningitis associated with the Leningrad-Zagreb mumps vaccine strain following mass vaccination with measles-mumps-rubella vaccine, Rio Grande do Sul, Brazil, 1997.

    Science.gov (United States)

    da Silveira, Claudio Marcos; Kmetzsch, Claudete Iris; Mohrdieck, Renate; Sperb, Alethea Fagundes; Prevots, D Rebecca

    2002-10-01

    Few data are available on the risk of aseptic meningitis following vaccination with the Leningrad-Zagreb (L-Z) strain of mumps vaccine. In 1997 the mumps vaccine was introduced into the state of Rio Grande do Sul in Brazil through mass vaccination with mumps-measles-rubella (MMR), targeting children aged 1-11 years. Five municipalities used exclusively MMR vaccine containing the L-Z strain of mumps. An outbreak of aseptic meningitis was observed shortly after the mass campaign. To estimate the risk of aseptic meningitis associated with this strain, we analysed vaccination and meningitis case surveillance data from the selected municipalities. A case of vaccine-associated aseptic meningitis was defined as one with a pleocytosis of 10-1,500 leukocytes/ml and occurring within 15-35 days after vaccine receipt. We estimated a risk of 2.9 cases per 10,000 doses of L-Z administered, equivalent to 1 case per 3,390 doses administered. The overall risk of aseptic meningitis following the campaign was increased 12.2-fold (95% CI: 6.0-24.7) compared with the same period in 1995-1996. Following the mass campaign, the incidence of mumps declined 93% during 1998-2000. Vaccination with the L-Z strain of mumps vaccine as part of a mass campaign was associated with a significantly increased risk of aseptic meningitis. Decisions about type of mumps vaccine and mumps vaccination strategies must consider vaccine safety issues in addition to other criteria.

  9. Molecular analysis of yellow fever virus 17DD vaccine strain

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    Paulo R. Post

    1991-06-01

    Full Text Available The Oswaldo Cruz Foundation produces most of the yellow fever (YF vaccine prepared world wide. As part of a broader approach to determine the genetic variability in YF l7D seeds and vaccines and its relevance to viral attenuation the 17DD virus was purifed directly from chick embryo homogenates which is the source of virus used for vaccination of millions of people in Brazil and other countries for half a century. Neutralization and hemagglutination tests showed that the purified virus is similar to the original stock. Furthermore, radioimmune precipitation of 35S-methionine-labeled viral proteins using mouse hyperimmune ascitic fluid revealed identical patterns for the purified 17DD virus and the YF l7D-204 strain except for the 17DD E protein which migrated slower on SDS-PAGE. This difference is likely to be due to N-linked glycosylation. Finally, comparison by northern blot nybridization of virion RNAs of purified 17DD with two other strains of YF virus only fenome-sized molecules for all three viruses. These observations suggest that vaccine phenotype is primarily associated with the accumulation of mutations.

  10. A wide extent of inter-strain diversity in virulent and vaccine strains of alphaherpesviruses.

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    Moriah L Szpara

    2011-10-01

    Full Text Available Alphaherpesviruses are widespread in the human population, and include herpes simplex virus 1 (HSV-1 and 2, and varicella zoster virus (VZV. These viral pathogens cause epithelial lesions, and then infect the nervous system to cause lifelong latency, reactivation, and spread. A related veterinary herpesvirus, pseudorabies (PRV, causes similar disease in livestock that result in significant economic losses. Vaccines developed for VZV and PRV serve as useful models for the development of an HSV-1 vaccine. We present full genome sequence comparisons of the PRV vaccine strain Bartha, and two virulent PRV isolates, Kaplan and Becker. These genome sequences were determined by high-throughput sequencing and assembly, and present new insights into the attenuation of a mammalian alphaherpesvirus vaccine strain. We find many previously unknown coding differences between PRV Bartha and the virulent strains, including changes to the fusion proteins gH and gB, and over forty other viral proteins. Inter-strain variation in PRV protein sequences is much closer to levels previously observed for HSV-1 than for the highly stable VZV proteome. Almost 20% of the PRV genome contains tandem short sequence repeats (SSRs, a class of nucleic acids motifs whose length-variation has been associated with changes in DNA binding site efficiency, transcriptional regulation, and protein interactions. We find SSRs throughout the herpesvirus family, and provide the first global characterization of SSRs in viruses, both within and between strains. We find SSR length variation between different isolates of PRV and HSV-1, which may provide a new mechanism for phenotypic variation between strains. Finally, we detected a small number of polymorphic bases within each plaque-purified PRV strain, and we characterize the effect of passage and plaque-purification on these polymorphisms. These data add to growing evidence that even plaque-purified stocks of stable DNA viruses exhibit

  11. A wide extent of inter-strain diversity in virulent and vaccine strains of alphaherpesviruses.

    Science.gov (United States)

    Szpara, Moriah L; Tafuri, Yolanda R; Parsons, Lance; Shamim, S Rafi; Verstrepen, Kevin J; Legendre, Matthieu; Enquist, L W

    2011-10-01

    Alphaherpesviruses are widespread in the human population, and include herpes simplex virus 1 (HSV-1) and 2, and varicella zoster virus (VZV). These viral pathogens cause epithelial lesions, and then infect the nervous system to cause lifelong latency, reactivation, and spread. A related veterinary herpesvirus, pseudorabies (PRV), causes similar disease in livestock that result in significant economic losses. Vaccines developed for VZV and PRV serve as useful models for the development of an HSV-1 vaccine. We present full genome sequence comparisons of the PRV vaccine strain Bartha, and two virulent PRV isolates, Kaplan and Becker. These genome sequences were determined by high-throughput sequencing and assembly, and present new insights into the attenuation of a mammalian alphaherpesvirus vaccine strain. We find many previously unknown coding differences between PRV Bartha and the virulent strains, including changes to the fusion proteins gH and gB, and over forty other viral proteins. Inter-strain variation in PRV protein sequences is much closer to levels previously observed for HSV-1 than for the highly stable VZV proteome. Almost 20% of the PRV genome contains tandem short sequence repeats (SSRs), a class of nucleic acids motifs whose length-variation has been associated with changes in DNA binding site efficiency, transcriptional regulation, and protein interactions. We find SSRs throughout the herpesvirus family, and provide the first global characterization of SSRs in viruses, both within and between strains. We find SSR length variation between different isolates of PRV and HSV-1, which may provide a new mechanism for phenotypic variation between strains. Finally, we detected a small number of polymorphic bases within each plaque-purified PRV strain, and we characterize the effect of passage and plaque-purification on these polymorphisms. These data add to growing evidence that even plaque-purified stocks of stable DNA viruses exhibit limited sequence

  12. [Comparative analysis on the complete genome sequence of mumps epidemic strain and mumps vaccine strain S79 isolated in Zhejiang province, China between year 2005 and 2010].

    Science.gov (United States)

    Zhang, Dong-Yan; Feng, Yan; Zhong, Shu-Ling; Lu, Yi-Yu; Zhuang, Fang-Cheng; Xu, Chang-Ping

    2012-03-01

    To compare the differences in the complete genome sequence between mumps epidemic strain and mumps vaccine strain S79 isolated in Zhejiang province. A total of 4 mumps epidemic strains, which were separated from Zhejiang province during 2005 to 2010, named as ZJ05-1, ZJ06-3, ZJ08-1 and ZJ10-1 were selected in the study. The complete genome sequences were amplified using RT-PCR. The genetic differences between vaccine strain S79 and other genotype strains were compared; while the genetic-distance was calculated and the evolution was analyzed. The biggest difference between the 4 epidemic strains and the vaccine strain S79 was found on the membrane associated protein gene; whose average nucleotide differential number was 42.5 +/- 3.0 and the average variant ratio was 13.6%; while the mean amino acid differential number was 12.8 +/- 1.5 and the average variant ratio was 22.4%. The smallest difference among the 4 epidemic strains and the vaccine strain was found in stromatin genes, whose average nucleotide differential number was 73.8 +/- 2.5 and the average variant ratio was 5.9%; while the mean amino acid differential number was 3.0 +/- 0.8 and the average variant ratio was 0.8%. The dn/ds value of the stromatin genes of the 4 epidemic strains reached the highest, as 0.6526; but without any positive pressure (dn/ds 0.05). There were mutations happened on the known antigen epitope, as 8th amino acid of membrane associated protein genes and on the 336th and 356th amino acid of hemagglutinin/neuraminidase proteins. Compared with the vaccine strain, the glycosylation sites of ZJ05-1, ZJ06-3, ZJ08-1 and ZJ10-1 increased 1, 1, 2 and 2 respectively. The complete amino acid sequence of all strains showed that there were 17 characteristic sites found on the genotype-F mumps strain. Within the complete genome, the genetic-distance between epidemic strains and vaccine strains in Zhejiang province (0.071) was significantly larger than the genetic-distance between strains in

  13. Classical Swine Fever Outbreak after Modified Live LOM Strain Vaccination in Naive Pigs, South Korea

    Science.gov (United States)

    Je, Sang H.; Kwon, Taeyong; Yoo, Sung J.; Lee, Dong-Uk; Lee, SeungYoon; Richt, Juergen A.

    2018-01-01

    We report classical swine fever outbreaks occurring in naive pig herds on Jeju Island, South Korea, after the introduction of the LOM vaccine strain. Two isolates from sick pigs had >99% identity with the vaccine stain. LOM strain does not appear safe; its use in the vaccine should be reconsidered. PMID:29553332

  14. Immunoproteomics analysis of the murine antibody response to vaccination with an improved Francisella tularensis live vaccine strain (LVS.

    Directory of Open Access Journals (Sweden)

    Susan M Twine

    2010-04-01

    Full Text Available Francisella tularensis subspecies tularensis is the causative agent of a spectrum of diseases collectively known as tularemia. An attenuated live vaccine strain (LVS has been shown to be efficacious in humans, but safety concerns have prevented its licensure by the FDA. Recently, F. tularensis LVS has been produced under Current Good Manufacturing Practice (CGMP guidelines. Little is known about the immunogenicity of this new vaccine preparation in comparison with extensive studies conducted with laboratory passaged strains of LVS. Thus, the aim of the current work was to evaluate the repertoire of antibodies produced in mouse strains vaccinated with the new LVS vaccine preparation.In the current study, we used an immunoproteomics approach to examine the repertoire of antibodies induced following successful immunization of BALB/c versus unsuccessful vaccination of C57BL/6 mice with the new preparation of F. tularensis LVS. Successful vaccination of BALB/c mice elicited antibodies to nine identified proteins that were not recognized by antisera from vaccinated but unprotected C57BL/6 mice. In addition, the CGMP formulation of LVS stimulated a greater repertoire of antibodies following vaccination compared to vaccination with laboratory passaged ATCC LVS strain. A total of 15 immunoreactive proteins were identified in both studies, however, 16 immunoreactive proteins were uniquely reactive with sera from the new formulation of LVS.This is the first report characterising the antibody based immune response of the new formulation of LVS in the widely used murine model of tularemia. Using two mouse strains, we show that successfully vaccinated mice can be distinguished from unsuccessfully vaccinated mice based upon the repertoire of antibodies generated. This opens the door towards downselection of antigens for incorporation into tularemia subunit vaccines. In addition, this work also highlights differences in the humoral immune response to

  15. Low dose vaccination with attenuated Francisella tularensis strain SchuS4 mutants protects against tularemia independent of the route of vaccination.

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    Dedeke Rockx-Brouwer

    Full Text Available Tularemia, caused by the gram-negative bacterium Francisella tularensis, is a severe, sometimes fatal disease. Interest in tularemia has increased over the last decade due to its history as a biological weapon. In particular, development of novel vaccines directed at protecting against pneumonic tularemia has been an important goal. Previous work has demonstrated that, when delivered at very high inoculums, administration of live, highly attenuated strains of virulent F. tularensis can protect against tularemia. However, lower vaccinating inoculums did not offer similar immunity. One concern of using live vaccines is that the host may develop mild tularemia in response to infection and use of high inoculums may contribute to this issue. Thus, generation of a live vaccine that can efficiently protect against tularemia when delivered in low numbers, e.g. <100 organisms, may address this concern. Herein we describe the ability of three defined, attenuated mutants of F. tularensis SchuS4, deleted for FTT0369c, FTT1676, or FTT0369c and FTT1676, respectively, to engender protective immunity against tularemia when delivered at concentrations of approximately 50 or fewer bacteria. Attenuated strains for use as vaccines were selected by their inability to efficiently replicate in macrophages in vitro and impaired replication and dissemination in vivo. Although all strains were defective for replication in vitro within macrophages, protective efficacy of each attenuated mutant was correlated with their ability to modestly replicate and disseminate in the host. Finally, we demonstrate the parenteral vaccination with these strains offered superior protection against pneumonic tularemia than intranasal vaccination. Together our data provides proof of principle that low dose attenuated vaccines may be a viable goal in development of novel vaccines directed against tularemia.

  16. Sequencing and characterization of Varicella-Zoster virus vaccine strain SuduVax

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    Kim Jong

    2011-12-01

    Full Text Available Abstract Background Varicella-zoster virus (VZV causes chickenpox in children and shingles in older people. Currently, live attenuated vaccines based on the Oka strain are available worldwide. In Korea, an attenuated VZV vaccine has been developed from a Korean isolate and has been commercially available since 1994. Despite this long history of use, the mechanism for the attenuation of the vaccine strain is still elusive. We attempted to understand the molecular basis of attenuation mechanism by full genome sequencing and comparative genomic analyses of the Korean vaccine strain SuduVax. Results SuduVax was found to contain a genome that was 124,759 bp and possessed 74 open reading frames (ORFs. SuduVax was genetically most close to Oka strains and these Korean-Japanese strains formed a strong clade in phylogenetic trees. SuduVax, similar to the Oka vaccine strains, underwent T- > C substitution at the stop codon of ORF0, resulting in a read-through mutation to code for an extended form of ORF0 protein. SuduVax also shared certain deletion and insertion mutations in ORFs 17, 29, 56 and 60 with Oka vaccine strains and some clinical strains. Conclusions The Korean VZV vaccine strain SuduVax is genetically similar to the Oka vaccine strains. Further comparative genomic and bioinformatics analyses will help to elucidate the molecular basis of the attenuation of the VZV vaccine strains.

  17. Isolation of an attenuated myxoma virus field strain that can confer protection against myxomatosis on contacts of vaccinates.

    Science.gov (United States)

    Bárcena, J; Pagès-Manté, A; March, R; Morales, M; Ramírez, M A; Sánchez-Vizcaíno, J M; Torres, J M

    2000-01-01

    Twenty MV strains obtained from a survey of field strains currently circulating throughout Spain were analyzed for their virulence and horizontal spreading among rabbits by contact transmission. A virus strain with suitable characteristics to be used as a potential vaccine against myxomatosis in wild rabbit populations was selected. Following inoculation, the selected MV strain elicited high levels of MV specific antibodies and induced protection of rabbits against a virulent MV challenge. Furthermore, the attenuated MV was transmitted to 9 out of 16 uninoculated rabbits by contact, inducing protection against myxomatosis.

  18. Universal or Specific? A Modeling-Based Comparison of Broad-Spectrum Influenza Vaccines against Conventional, Strain-Matched Vaccines.

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    Rahul Subramanian

    2016-12-01

    Full Text Available Despite the availability of vaccines, influenza remains a major public health challenge. A key reason is the virus capacity for immune escape: ongoing evolution allows the continual circulation of seasonal influenza, while novel influenza viruses invade the human population to cause a pandemic every few decades. Current vaccines have to be updated continually to keep up to date with this antigenic change, but emerging 'universal' vaccines-targeting more conserved components of the influenza virus-offer the potential to act across all influenza A strains and subtypes. Influenza vaccination programmes around the world are steadily increasing in their population coverage. In future, how might intensive, routine immunization with novel vaccines compare against similar mass programmes utilizing conventional vaccines? Specifically, how might novel and conventional vaccines compare, in terms of cumulative incidence and rates of antigenic evolution of seasonal influenza? What are their potential implications for the impact of pandemic emergence? Here we present a new mathematical model, capturing both transmission dynamics and antigenic evolution of influenza in a simple framework, to explore these questions. We find that, even when matched by per-dose efficacy, universal vaccines could dampen population-level transmission over several seasons to a greater extent than conventional vaccines. Moreover, by lowering opportunities for cross-protective immunity in the population, conventional vaccines could allow the increased spread of a novel pandemic strain. Conversely, universal vaccines could mitigate both seasonal and pandemic spread. However, where it is not possible to maintain annual, intensive vaccination coverage, the duration and breadth of immunity raised by universal vaccines are critical determinants of their performance relative to conventional vaccines. In future, conventional and novel vaccines are likely to play complementary roles in

  19. Capripox disease in Ethiopia: Genetic differences between field isolates and vaccine strain, and implications for vaccination failure

    International Nuclear Information System (INIS)

    Gelaye, E.; Belay, A.; Melesse, A.G.; Jenberie, S.; Yami, M.; Loitsch, A.; Tuppurainen, E.; Grabherr, R.; Diallo, A.; Lamien, C.E.

    2015-01-01

    Sheeppox virus (SPPV), goatpox virus (GTPV) and lumpy skin disease virus (LSDV) of the genus Capripoxvirus (CaPV) cause capripox disease in sheep, goats and cattle, respectively. These viruses are not strictly host-specific and their geographical distribution is complex. In Ethiopia, where sheep, goats and cattle are all affected, a live attenuated vaccine strain (KS1-O180) is used for immunization of both small ruminants and cattle. Although occurrences of the disease in vaccinated cattle are frequently reported, information on the circulating isolates and their relation to the vaccine strain in use are still missing. The present study addressed the parameters associated with vaccination failure in Ethiopia

  20. Respiratory and oral vaccination improves protection conferred by the live vaccine strain against pneumonic tularemia in the rabbit model.

    Science.gov (United States)

    Stinson, Elizabeth; Smith, Le'Kneitah P; Cole, Kelly Stefano; Barry, Eileen M; Reed, Douglas S

    2016-10-01

    Tularemia is a severe, zoonotic disease caused by a gram-negative bacterium, Francisella tularensis We have previously shown that rabbits are a good model of human pneumonic tularemia when exposed to aerosols containing a virulent, type A strain, SCHU S4. We further demonstrated that the live vaccine strain (LVS), an attenuated type B strain, extended time to death when given by scarification. Oral or aerosol vaccination has been previously shown in humans to offer superior protection to parenteral vaccination against respiratory tularemia challenge. Both oral and aerosol vaccination with LVS were well tolerated in the rabbit with only minimal fever and no weight loss after inoculation. Plasma antibody titers against F. tularensis were higher in rabbits that were vaccinated by either oral or aerosol routes compared to scarification. Thirty days after vaccination, all rabbits were challenged with aerosolized SCHU S4. LVS given by scarification extended time to death compared to mock-vaccinated controls. One orally vaccinated rabbit did survive aerosol challenge, however, only aerosol vaccination extended time to death significantly compared to scarification. These results further demonstrate the utility of the rabbit model of pneumonic tularemia in replicating what has been reported in humans and macaques as well as demonstrating the utility of vaccination by oral and respiratory routes against an aerosol tularemia challenge. © FEMS 2016. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  1. Molecular characterization of rotavirus strains from pre- and post-vaccination periods in a country with low vaccination coverage: the case of Slovenia.

    Science.gov (United States)

    Steyer, Andrej; Sagadin, Martin; Kolenc, Marko; Poljšak-Prijatelj, Mateja

    2014-12-01

    Rotavirus vaccination started in Slovenia in 2007 on a voluntarily basis. The vaccination rate is relatively low (up to 27%) and no increasing trend is observed. We present rotavirus genotype distribution among children hospitalized for rotavirus gastroenteritis in Slovenia. Eight consecutive rotavirus seasons were followed, from 2005/06 to 2012/13, and 113 strains of the most common rotavirus genotypes were randomly selected for molecular characterization of rotavirus VP7 and VP4 (VP8(∗)) genome segments. During the vaccine introduction period, from 2007 to 2013, rotavirus genotype prevalences changed, with G1P[8] decreasing from 74.1% to 8.7% between 2007/08 and 2010/11 seasons, replaced by G4P[8] and G2P[4], with up to 52.0% prevalence. Comparable analysis of VP7 and VP8(∗) genome fragments within G1P[8] genotype lineages revealed considerable differences for rotavirus strains circulating before and during the vaccination period. The G1P[8] rotavirus strains from the pre-vaccination period clustered in a phylogenetic tree within Rotarix®-like VP7 and VP8(∗) lineages. However, since 2007, the majority of G1P[8] strains have shifted to distant genetic lineages with lower nucleotide (88.1-94.0% for VP7 and 86.6-91.1% for VP8(∗)) and amino acid (93.8-95.2% for VP7 and 85.3-94.6% for VP8(∗)) identities to the vaccine Rotarix® strain. This change also resulted in a different deduced amino acid profile at the major VP7 and VP8(∗) antigenic epitopes. Copyright © 2014 The Authors. Published by Elsevier B.V. All rights reserved.

  2. Comparative analysis of pentavalent rotavirus vaccine strains and G8 rotaviruses identified during vaccine trial in Africa.

    Science.gov (United States)

    Heylen, Elisabeth; Zeller, Mark; Ciarlet, Max; Lawrence, Jody; Steele, Duncan; Van Ranst, Marc; Matthijnssens, Jelle

    2015-10-06

    RotaTeqTM is a pentavalent rotavirus vaccine based on a bovine rotavirus genetic backbone in vitro reassorted with human outer capsid genes. During clinical trials of RotaTeqTM in Sub-Saharan Africa, the vaccine efficacy over a 2-year follow-up was lower against the genotypes contained in the vaccine than against the heterotypic G8P[6] and G8P[1] rotavirus strains of which the former is highly prevalent in Africa. Complete genome analyses of 43 complete rotavirus genomes collected during phase III clinical trials of RotaTeqTM in Sub-Saharan Africa, were conducted to gain insight into the high level of cross-protection afforded by RotaTeqTM against these G8 strains. Phylogenetic analysis revealed the presence of a high number of bovine rotavirus gene segments in these human G8 strains. In addition, we performed an in depth analysis on the individual amino acid level which showed that G8 rotaviruses were more similar to the RotaTeqTM vaccine than non-G8 strains. Because RotaTeqTM possesses a bovine genetic backbone, the high vaccine efficacy against G8 strains might be partially explained by the fact that all these strains contain a complete or partial bovine-like backbone. Altogether, this study supports the hypothesis that gene segments other than VP7 and VP4 play a role in vaccine-induced immunity.

  3. Complete Genomic Sequences of H3N8 Equine Influenza Virus Strains Used as Vaccine Strains in Japan.

    Science.gov (United States)

    Nemoto, Manabu; Yamanaka, Takashi; Bannai, Hiroshi; Tsujimura, Koji; Kokado, Hiroshi

    2018-03-22

    We sequenced the eight segments of influenza A virus strains A/equine/Ibaraki/1/2007 and A/equine/Yokohama/aq13/2010, which are strains of the Florida sublineage clades 1 and 2 of the H3N8 subtype equine influenza virus. These strains have been used as vaccine strains in Japan since 2016 in accordance with World Organization for Animal Health (OIE) recommendations. Copyright © 2018 Nemoto et al.

  4. The serological response of young dogs to the Flury LEP strain of rabies virus vaccine.

    Science.gov (United States)

    Aghomo, H O; Oduye, O O; Rupprecht, C E

    1990-01-01

    The serological response of puppies from Nigeria to live Flury low egg passage (LEP) rabies vaccine was determined. Two sets of puppies were used: one set from rabies-vaccinated bitches and another set from non-vaccinated bitches. Puppies were vaccinated intramuscularly with Flury LEP strain rabies vaccine and serially bled from the 4th week to the 30th week. Serum rabies virus neutralizing antibodies (VNA) were measured by a modified rapid fluorescent focus inhibition test (RFFIT). Puppies from non-vaccinated bitches responded well to vaccination after the 4th week and through to the 10th week of age, showing a progressive increase in VNA. In contrast, puppies from vaccinated bitches responded well to rabies vaccination only at 10 weeks of age, although detectable maternal rabies VNA and rabies anti-ribonucleoprotein (RNP) antibodies had decreased by 6 weeks post partum.

  5. Identification of the immunogenic spore and vegetative proteins of Bacillus anthracis vaccine strain A16R.

    Directory of Open Access Journals (Sweden)

    Xiankai Liu

    Full Text Available Immunoproteomics was used to screen the immunogenic spore and vegetative proteins of Bacillus anthracis vaccine strain A16R. The spore and vegetative proteins were separated by 2D gel electrophoresis and transferred to polyvinylidene difluoride membranes, and then western blotting was performed with rabbit immune serum against B.anthracis live spores. Immunogenic spots were cut and digested by trypsin. Matrix-assisted laser desorption ionization time-of-flight mass spectrometry was performed to identify the proteins. As a result, 11 and 45 immunogenic proteins were identified in the spores and vegetative cells, respectively; 26 of which have not been reported previously. To verify their immunogenicity, 12 of the identified proteins were selected to be expressed, and the immune sera from the mice vaccinated by the 12 expressed proteins, except BA0887, had a specific western blot band with the A16R whole cellular lytic proteins. Some of these immunogenic proteins might be used as novel vaccine candidates themselves or for enhancing the protective efficacy of a protective-antigen-based vaccine.

  6. Making evidence-based selections of influenza vaccines

    OpenAIRE

    Childress, Billy-Clyde; Montney, Joshua D; Albro, Elise A

    2014-01-01

    Years ago, intramuscular influenza vaccines were the only option for those who wanted to arm themselves against the flu. Today there are alternatives, including intradermal injections and intranasal sprays. In order to select the right influenza vaccine for their patients, pharmacists, and other healthcare professionals must have a basic understanding of the immune system. Influenza vaccines elicit different levels of immune response involving innate and adaptive immunity, which are critical ...

  7. Vaccine-induced rabies case in a cow (Bos taurus): Molecular characterisation of vaccine strain in brain tissue.

    Science.gov (United States)

    Vuta, Vlad; Picard-Meyer, Evelyne; Robardet, Emmanuelle; Barboi, Gheorghe; Motiu, Razvan; Barbuceanu, Florica; Vlagioiu, Constantin; Cliquet, Florence

    2016-09-22

    Rabies is a fatal neuropathogenic zoonosis caused by the rabies virus of the Lyssavirus genus, Rhabdoviridae family. The oral vaccination of foxes - the main reservoir of rabies in Europe - using a live attenuated rabies virus vaccine was successfully conducted in many Western European countries. In July 2015, a rabies vaccine strain was isolated from the brain tissues of a clinically suspect cow (Bos taurus) in Romania. The nucleotide analysis of both N and G gene sequences showed 100% identity between the rabid animal, the GenBank reference SAD B19 strain and five rabies vaccine batches used for the national oral vaccination campaign targeting foxes. Copyright © 2016 Elsevier Ltd. All rights reserved.

  8. Molecular characterisation and nucleotide sequence analysis of canine parvovirus strains in vaccines in India

    Directory of Open Access Journals (Sweden)

    Sukdeb Nandi

    2010-03-01

    Full Text Available Canine parvovirus 2 (CPV‑2 is one of the most important viruses that causes haemorrhagic gastroenteritis and myocarditis of dogs worldwide. The picture has been complicated further due to the emergence of new mutants of CPV, namely: CPV‑2a, CPV‑2b and CPV‑2c. In this study, the molecular characterisation of strains present in the CPV vaccines available on the Indian market was performed using polymerase chain reaction and DNA sequencing. The VP1/VP2 genes of two vaccine strains and a field strain (Bhopal were sequenced and the nucleotide and the deduced amino acid sequences were compared. The results indicated that the isolate belonged to CPV type 2b and the strains in the vaccines belonged to type CPV‑2. From the study, it is inferred that the CPV strain used in commercially available vaccine preparation differed from the strains present in CPV infection in dogs in India

  9. Molecular characterisation and nucleotide sequence analysis of canine parvovirus strains in vaccines in India.

    Science.gov (United States)

    Nandi, Sukdeb; Anbazhagan, Rajendra; Kumar, Manoj

    2010-01-01

    Canine parvovirus 2 (CPV-2) is one of the most important viruses that causes haemorrhagic gastroenteritis and myocarditis of dogs worldwide. The picture has been complicated further due to the emergence of new mutants of CPV, namely: CPV-2a, CPV-2b and CPV-2c. In this study, the molecular characterisation of strains present in the CPV vaccines available on the Indian market was performed using polymerase chain reaction and DNA sequencing. The VP1/VP2 genes of two vaccine strains and a field strain (Bhopal) were sequenced and the nucleotide and the deduced amino acid sequences were compared. The results indicated that the isolate belonged to CPV type 2b and the strains in the vaccines belonged to type CPV-2. From the study, it is inferred that the CPV strain used in commercially available vaccine preparation differed from the strains present in CPV infection in dogs in India.

  10. DIVA vaccine properties of the live chimeric pestivirus strain CP7_E2gif.

    Science.gov (United States)

    von Rosen, Tanya; Rangelova, Desislava; Nielsen, Jens; Rasmussen, Thomas Bruun; Uttenthal, Åse

    2014-06-04

    Live modified vaccines to protect against classical swine fever virus (CSFV), based on chimeric pestiviruses, have been developed to enable serological Differentiation of Infected from Vaccinated Animals (DIVA). In this context, the chimeric virus CP7_E2gif vaccine candidate is unique as it does not include any CSFV components. In the present study, the DIVA vaccine properties of CP7_E2gif were evaluated in comparison to the conventional live attenuated Riemser C-strain vaccine. Sera and tonsil samples obtained from pigs immunised with these two vaccines were analysed. No viral RNA was found in serum after vaccination with CP7_E2gif, whereas some serum samples from C-strain vaccinated animals were positive. In both vaccinated groups, individual viral RNA-positive tonsil samples were detected in animals euthanised between 7 and 21 days post vaccination. Furthermore, serum samples from these animals, together with archival samples from pigs vaccinated with CP7_E2gif and subsequently CSFV challenged, were analysed for specific antibodies using ELISAs and for homologous neutralising antibodies. In animals vaccinated with CP7_E2gif, neutralising antibodies were detected from day 10. However, the sera remained negative for anti-CSFV E2-specific antibodies whereas pigs vaccinated with C-strain seroconverted against CSFV by 14 days after vaccination, as determined by a CSFV-E2 specific blocking ELISA. One week after subsequent CSFV challenge, a strong anti-CSFV E2 reaction was detected in CP7_E2gif vaccinated pigs and anti-E(rns) antibodies were detected from 10 days after infection. In conclusion, CP7_E2gif has the potential to be used as a DIVA vaccine in combination with detection of anti-CSFV E2-specific antibodies. Copyright © 2014 Elsevier B.V. All rights reserved.

  11. Lights and shades on an historical vaccine canine distemper virus, the Rockborn strain.

    Science.gov (United States)

    Martella, V; Blixenkrone-Møller, M; Elia, G; Lucente, M S; Cirone, F; Decaro, N; Nielsen, L; Bányai, K; Carmichael, L E; Buonavoglia, C

    2011-02-01

    Both egg- and cell-adapted canine distemper virus (CDV) vaccines are suspected to retain residual virulence, especially if administered to immuno-suppressed animals, very young pups or to highly susceptible animal species. In the early 1980s, post-vaccine encephalitis was reported in dogs from various parts of Britain after administration of a particular batch of combined CDV Rockborn strain/canine adenovirus type-1 vaccine, although incrimination of the Rockborn strain was subsequently retracted. Notwithstanding, this, and other reports, led to the view that the Rockborn strain is less attenuated and less safe than other CDV vaccines, and the Rockborn strain was officially withdrawn from the markets in the mid 1990s. By sequencing the H gene of the strain Rockborn from the 46th laboratory passage, and a commercial vaccine (Candur(®) SH+P, Hoechst Rousell Vet GmbH), the virus was found to differ from the commonly used vaccine strain, Onderstepoort (93.0% nt and 91.7% aa), and to resemble more closely (99.6% nt and 99.3% aa) a CDV strain detected in China from a Lesser Panda (Ailurus fulgens). An additional four CDV strains matching (>99% nt identity) the Rockborn virus were identified in the sequence databases. Also, Rockborn-like strains were identified in two vaccines currently in the market. These findings indicate that Rockborn-like viruses may be recovered from dogs or other carnivores with distemper, suggesting cases of residual virulence of vaccines, or circulation of vaccine-derived Rockborn-like viruses in the field. Copyright © 2010 Elsevier Ltd. All rights reserved.

  12. Lights and shades on an historical vaccine canine distemper virus, the Rockborn strain

    DEFF Research Database (Denmark)

    Martella, V.; Blixenkrone-Møller, Merete; Elia, G.

    2011-01-01

    Both egg- and cell-adapted canine distemper virus (CDV) vaccines are suspected to retain residual virulence, especially if administered to immuno-suppressed animals, very young pups or to highly susceptible animal species. In the early 1980s, post-vaccine encephalitis was reported in dogs from...... in the sequence databases. Also, Rockborn-like strains were identified in two vaccines currently in the market. These findings indicate that Rockborn-like viruses may be recovered from dogs or other carnivores with distemper, suggesting cases of residual virulence of vaccines, or circulation of vaccine...

  13. Correlation of genetic variability with safety of mumps vaccine Urabe AM9 strain.

    Science.gov (United States)

    Amexis, G; Fineschi, N; Chumakov, K

    2001-08-15

    The Urabe AM9 strain of mumps vaccine live is known for its genetic instability and some vaccines derived from this strain were withdrawn from the market due to an excessive number of vaccine-associated parotitis and meningitis cases. To identify the molecular basis of this instability, we determined complete nucleotide sequences of several stocks of the Urabe strain used for vaccine production by different manufacturers and of two clinical isolates from cases of vaccine-associated meningitis. In contrast to previously published studies relating the Lys335 --> Glu mutation in the viral HN gene with neurovirulence of mumps virus, we could not confirm any association of this mutation with the safety of mumps vaccine. Each of the three vaccine stocks studied had its own characteristic profile of mutations that was identified by cDNA sequencing and quantitated by mutant analysis by PCR and restriction enzyme cleavage. Determination of the mutational profile of mumps vaccine lots could allow vaccine manufacturers to characterize seed viruses and monitor the consistency of vaccine production to prevent emergence of virulent revertants.

  14. Complex adenovirus-vectored vaccine protects guinea pigs from three strains of Marburg virus challenges

    International Nuclear Information System (INIS)

    Wang Danher; Hevey, Michael; Juompan, Laure Y.; Trubey, Charles M.; Raja, Nicholas U.; Deitz, Stephen B.; Woraratanadharm, Jan; Luo Min; Yu Hong; Swain, Benjamin M.; Moore, Kevin M.; Dong, John Y.

    2006-01-01

    The Marburg virus (MARV), an African filovirus closely related to the Ebola virus, causes a deadly hemorrhagic fever in humans, with up to 90% mortality. Currently, treatment of disease is only supportive, and no vaccines are available to prevent spread of MARV infections. In order to address this need, we have developed and characterized a novel recombinant vaccine that utilizes a single complex adenovirus-vectored vaccine (cAdVax) to overexpress a MARV glycoprotein (GP) fusion protein derived from the Musoke and Ci67 strains of MARV. Vaccination with the cAdVaxM(fus) vaccine led to efficient production of MARV-specific antibodies in both mice and guinea pigs. Significantly, guinea pigs vaccinated with at least 5 x 10 7 pfu of cAdVaxM(fus) vaccine were 100% protected against lethal challenges by the Musoke, Ci67 and Ravn strains of MARV, making it a vaccine with trivalent protective efficacy. Therefore, the cAdVaxM(fus) vaccine serves as a promising vaccine candidate to prevent and contain multi-strain infections by MARV

  15. Phase II and III Clinical Studies of Diphtheria-Tetanus-Acellular Pertussis Vaccine Containing Inactivated Polio Vaccine Derived from Sabin Strains (DTaP-sIPV).

    Science.gov (United States)

    Okada, Kenji; Miyazaki, Chiaki; Kino, Yoichiro; Ozaki, Takao; Hirose, Mizuo; Ueda, Kohji

    2013-07-15

    Phase II and III clinical studies were conducted to evaluate immunogenicity and safety of a novel DTaP-IPV vaccine consisting of Sabin inactivated poliovirus vaccine (sIPV) and diphtheria-tetanus-acellular pertussis vaccine (DTaP). A Phase II study was conducted in 104 healthy infants using Formulation H of the DTaP-sIPV vaccine containing high-dose sIPV (3, 100, and 100 D-antigen units for types 1, 2, and 3, respectively), and Formulations M and L, containing half and one-fourth of the sIPV in Formulation H, respectively. Each formulation was administered 3 times for primary immunization and once for booster immunization. A Phase III study was conducted in 342 healthy infants who received either Formulation M + oral polio vaccine (OPV) placebo or DTaP + OPV. The OPV or OPV placebo was orally administered twice between primary and booster immunizations. Formulation M was selected as the optimum dose. In the Phase III study, the seropositive rate was 100% for all Sabin strains after primary immunization, and the neutralizing antibody titer after booster immunization was higher than in the control group (DTaP + OPV). All adverse reactions were clinically acceptable. DTaP-sIPV was shown to be a safe and immunogenic vaccine. JapicCTI-121902 for Phase II study, JapicCTI-101075 for Phase III study (http://www.clinicaltrials.jp/user/cte_main.jsp).

  16. Brucella abortus Strain RB51 Vaccine: Immune Response after Calfhood Vaccination and Field Investigation in Italian Cattle Population

    Directory of Open Access Journals (Sweden)

    Manuela Tittarelli

    2008-01-01

    Full Text Available Immune response to Brucella abortus strain RB51 vaccine was measured in cattle vaccinated at calfhood. After an increase at day 6 post-vaccination (pv, the antibody level recorded in the 10 vaccinated animals remained constant for two months, and then progressively decreased. All vaccinated animals remained negative from day 162 pv to the end of the study (day 300 pv. Only at days 13 and 14 pv the RB51-CFT showed 100% sensitivity (credibility interval (CI 76.2%–100%. The results indicate that the possibility to use RB51-CFT for the identification of cattle vaccinated at calfhood with RB51 is limited in time. A field investigation was carried out on 26,975 sera collected on regional basis from the Italian cattle population. The study outcomes indicate that in case of RB51-CFT positive results observed in officially Brucellosis-free (OBF areas and, in any case, when an illegal use of RB51 vaccine is suspected, the use of the RB51-CFT alone is not sufficient to identify all the vaccinated animals. The design of a more sophisticated diagnostic protocol including an epidemiological investigation, the use of RB51-CFT, and the use of the skin test with RB51 as antigen is deemed more appropriate for the identification of RB51 vaccinated animals.

  17. The Latest in Vaccine Policies: Selected Issues in School Vaccinations, Healthcare Worker Vaccinations, and Pharmacist Vaccination Authority Laws.

    Science.gov (United States)

    Barraza, Leila; Schmit, Cason; Hoss, Aila

    2017-03-01

    This paper discusses recent changes to state legal frameworks for mandatory vaccination in the context of school and healthcare worker vaccination. It then discusses state laws that allow pharmacists the authority to vaccinate.

  18. [Virus strain specific serum neutralizing antibodies in children and adolescents immunized with a Russian mumps vaccine].

    Science.gov (United States)

    Otrashevskaia, E V; Krasil'nikov, I V; Ignat'ev, G M

    2010-01-01

    Postvaccination immunity was studied in the children and teenagers without a history of clinical mumps infection, who had been immunized with the Leningrad-3 mumps vaccine. The level of specific lgG in ELISA and that and spectrum of their neutralizing activity against a vaccine strain and three heterologous mumps virus (MV) strains (genotypes A, C, and H) were measured. The investigation included 151 sera from the vaccinees aged 3 to 17 years, possessing the detectable specific IgG titers in ELISA and the detectable neutralizing titers against the vaccine strain. 97.4% of the vaccinees had neutralizing activity against 1-3 heterologous MV strains. A preponderance of neutralizing titers against heterologous MV strains by 1-log2 in some sera (6.5-32.5 depending on age) was most likely to suggest that the vaccinees' had been in contact with these virus strains in the past. In our investigation, a combination of positive IgG titers and neutralizing titers against the vaccine strain 2-log2 or higher provided the protection of the vaccinated children and teenagers against the symptomatic infection. There was a pronounced buster effect of the second immunization and a drop in the neutralizing activity of the sera from the vaccinated children and adolescents over time after the first and second immunization.

  19. Genotypic characterization by multi locus variable number of tandem repeats analysis international Bordetella pertussis vaccine strains

    Directory of Open Access Journals (Sweden)

    M. Fatah Moghadam

    2017-10-01

    Full Text Available Background: In 1930's first whole cell pertussis vaccines became available to the public heralding a dramatic success in overcoming the global burden of the disease. To date only a handful of B. pertussis strains have been used by international/local pertussis vaccine manufacturers. Inevitable well-documented genetic changes in the world population of this pathogen have prompted serious questions on suitability of traditional vaccine strains protect human against currently circulating wild isolates of Bordetella pertussis. Objective: Analyzing the genetic diversity within the most frequently-used vaccine strains of B. pertussis in the world Methods: A recently developed multi locus variable number of tandem repeats analysis (MLVA genotyping system along with a bioinforamtic piece of analysis was conducted on 11 strain / substrains of B137, B203 (10536, C393, Cs, E476, Tohama I, J445 (134, B202 and J446 (509 plus 2 sub-strains of 134 and 509 that are used at Razi institute for preparation of pertussis vaccine. In this study have used 6 individual loci of VNTR1, VNTR3a, VNTR3b, VNTR4, VNTR5 and VNTR6. Findings: Six distinct genotypes were recognized among the examined strains by comparing our data with the Dutch MLVA databank. These were all new and not reported before in the database. Conclusion: This observation reiterates on necessity for detection of predominant native strains to include in vaccine preparations suitable for different countries.

  20. Identification and development of a promising novel mumps vaccine candidate strain.

    Science.gov (United States)

    Liang, Yan; Ma, Shaohui; Liu, Longding; Zhao, Hongling; Wang, Lichun; Jiang, Li; Xie, Zhongping; Dong, Chenghong; Li, Qihan

    2010-12-01

    Mumps epidemics are usually caused by airborne transmission of mumps virus (MuV) and have high morbidity in non-immunized children. Epidemiological studies in many regions of China show that the genotype F viral strain is the most prevalent. However, the genotype A strain is currently used to prepare vaccines. Regional epidemiological MuV data suggest a significant application for the development of live attenuated mumps vaccines targeting specific genotypes. This article reports the isolation and culture of a genotype F MuV candidate strain that could be used to prepare a live attenuated mumps vaccine. This strain is shown to have good immunological efficacy and stability in neurovirulence evaluations. This work should facilitate the implementation of mumps vaccination in mainland China by targeting the most prevalent MuV genotype, genotype F. Copyright © 2010 Institut Pasteur. Published by Elsevier SAS. All rights reserved.

  1. Genome Sequences of Three Vaccine Strains and Two Wild-Type Canine Distemper Virus Strains from a Recent Disease Outbreak in South Africa.

    Science.gov (United States)

    Loots, Angelika K; Du Plessis, Morné; Dalton, Desiré Lee; Mitchell, Emily; Venter, Estelle H

    2017-07-06

    Canine distemper virus causes global multihost infectious disease. This report details complete genome sequences of three vaccine and two new wild-type strains. The wild-type strains belong to the South African lineage, and all three vaccine strains to the America 1 lineage. This constitutes the first genomic sequences of this virus from South Africa. Copyright © 2017 Loots et al.

  2. A Francisella tularensis live vaccine strain that improves stimulation of antigen-presenting cells does not enhance vaccine efficacy.

    Directory of Open Access Journals (Sweden)

    Deanna M Schmitt

    Full Text Available Vaccination is a proven strategy to mitigate morbidity and mortality of infectious diseases. The methodology of identifying and testing new vaccine candidates could be improved with rational design and in vitro testing prior to animal experimentation. The tularemia vaccine, Francisella tularensis live vaccine strain (LVS, does not elicit complete protection against lethal challenge with a virulent type A Francisella strain. One factor that may contribute to this poor performance is limited stimulation of antigen-presenting cells. In this study, we examined whether the interaction of genetically modified LVS strains with human antigen-presenting cells correlated with effectiveness as tularemia vaccine candidates. Human dendritic cells infected with wild-type LVS secrete low levels of proinflammatory cytokines, fail to upregulate costimulatory molecules, and activate human T cells poorly in vitro. One LVS mutant, strain 13B47, stimulated higher levels of proinflammatory cytokines from dendritic cells and macrophages and increased costimulatory molecule expression on dendritic cells compared to wild type. Additionally, 13B47-infected dendritic cells activated T cells more efficiently than LVS-infected cells. A deletion allele of the same gene in LVS displayed similar in vitro characteristics, but vaccination with this strain did not improve survival after challenge with a virulent Francisella strain. In vivo, this mutant was attenuated for growth and did not stimulate T cell responses in the lung comparable to wild type. Therefore, stimulation of antigen-presenting cells in vitro was improved by genetic modification of LVS, but did not correlate with efficacy against challenge in vivo within this model system.

  3. Engineering and preclinical evaluation of attenuated nontyphoidal Salmonella strains serving as live oral vaccines and as reagent strains.

    Science.gov (United States)

    Tennant, Sharon M; Wang, Jin-Yuan; Galen, James E; Simon, Raphael; Pasetti, Marcela F; Gat, Orit; Levine, Myron M

    2011-10-01

    While nontyphoidal Salmonella (NTS) has long been recognized as a cause of self-limited gastroenteritis, it is becoming increasingly evident that multiple-antibiotic-resistant strains are also emerging as important causes of invasive bacteremia and focal infections, resulting in hospitalizations and deaths. We have constructed attenuated Salmonella enterica serovar Typhimurium and Salmonella enterica serovar Enteritidis strains that can serve as live oral vaccines and as "reagent strains" for subunit vaccine production in a safe and economical manner. Prototype attenuated vaccine strains CVD 1921 and CVD 1941, derived from the invasive wild-type strains S. Typhimurium I77 and S. Enteritidis R11, respectively, were constructed by deleting guaBA, encoding guanine biosynthesis, and clpP, encoding a master protease regulator. The clpP mutation resulted in a hyperflagellation phenotype. An additional deletion in fliD yielded reagent strains CVD 1923 and CVD 1943, respectively, which export flagellin monomers. Oral 50% lethal dose (LD₅₀) analyses showed that the NTS vaccine strains were all highly attenuated in mice. Oral immunization with CVD 1921 or CVD 1923 protected mice against lethal challenge with wild-type S. Typhimurium I77. Immunization with CVD 1941 but not CVD 1943 protected mice against lethal infection with S. Enteritidis R11. Immune responses induced by these strains included high levels of serum IgG anti-lipopolysaccharide (LPS) and anti-flagellum antibodies, with titers increasing progressively during the immunization schedule. Since S. Typhimurium and S. Enteritidis are the most common NTS serovars associated with invasive disease, these findings can pave the way for development of a highly effective, broad-spectrum vaccine against invasive NTS.

  4. Effect of challenge of pigs previously immunised with inactivated vaccines containing homologous and heterologous Mycoplasma hyopneumoniae strains

    Directory of Open Access Journals (Sweden)

    Villarreal Iris

    2012-01-01

    Full Text Available Abstract Background Mycoplasma hyopneumoniae is the primary cause of enzootic pneumonia in pigs. Although vaccination is an important control tool, the results observed under field conditions are variable. This may be due to antigenic differences between the strains circulating in pig herds and the vaccine strain. This study compared the protective efficacy of four bacterins against challenge infection with a highly virulent field strain of M. hyopneumoniae. Seventy eight, one-week old piglets were randomly assigned to five treatment groups (A, B, C, D, E, 14 piglets each, and a negative control group (F consisting of 8 piglets. All pigs were injected at 1 (D7 and 4 weeks of age (D28, with 2 ml of either a placebo or a bacterin based on selected M. hyopneumoniae strains, namely A (F7.2C, B (F20.1L, C (B2V1W20 1A-F, D (J strain, E (placebo; positive control, F (placebo; negative control. At D56, all pigs except those of group F were challenged intratracheally with 7 ml culture medium containing 107 CCU/ml of M. hyopneumoniae strain F7.2C. All pigs were euthanized and necropsied at D84. The severity of coughing and pneumonia lesions were the main parameters. Immunofluorescence (IF testing, nested PCR testing of bronchoalveolar lavage (BAL fluid and serology for M. hyopneumoniae were also performed. Results The different bacterins only slightly improved clinical symptoms (average 0.38 in vaccinated groups vs. 0.45 in group E and histopathological lung lesions (average 3.20 in vaccinated groups vs. 3.45 in group E, but did not improve macroscopic lung lesions (score 4.30 vs. 4.03 in group E. None of the vaccines was significantly and/or consistently better or worse than the other ones. All bacterins evoked a serological response in the vaccinated animals. All pigs, except those from group F, were positive with nPCR in BAL fluid at D84. Conclusion The bacterins did not induce a clear overall protection against challenge infection, and there were no

  5. Effect of challenge of pigs previously immunised with inactivated vaccines containing homologous and heterologous Mycoplasma hyopneumoniae strains.

    Science.gov (United States)

    Villarreal, Iris; Vranckx, Katleen; Calus, Dries; Pasmans, Frank; Haesebrouck, Freddy; Maes, Dominiek

    2012-01-06

    Mycoplasma hyopneumoniae is the primary cause of enzootic pneumonia in pigs. Although vaccination is an important control tool, the results observed under field conditions are variable. This may be due to antigenic differences between the strains circulating in pig herds and the vaccine strain. This study compared the protective efficacy of four bacterins against challenge infection with a highly virulent field strain of M. hyopneumoniae. Seventy eight, one-week old piglets were randomly assigned to five treatment groups (A, B, C, D, E), 14 piglets each, and a negative control group (F) consisting of 8 piglets. All pigs were injected at 1 (D7) and 4 weeks of age (D28), with 2 ml of either a placebo or a bacterin based on selected M. hyopneumoniae strains, namely A (F7.2C), B (F20.1L), C (B2V1W20 1A-F), D (J strain), E (placebo; positive control), F (placebo; negative control). At D56, all pigs except those of group F were challenged intratracheally with 7 ml culture medium containing 107 CCU/ml of M. hyopneumoniae strain F7.2C. All pigs were euthanized and necropsied at D84. The severity of coughing and pneumonia lesions were the main parameters. Immunofluorescence (IF) testing, nested PCR testing of bronchoalveolar lavage (BAL) fluid and serology for M. hyopneumoniae were also performed. The different bacterins only slightly improved clinical symptoms (average 0.38 in vaccinated groups vs. 0.45 in group E) and histopathological lung lesions (average 3.20 in vaccinated groups vs. 3.45 in group E), but did not improve macroscopic lung lesions (score 4.30 vs. 4.03 in group E). None of the vaccines was significantly and/or consistently better or worse than the other ones. All bacterins evoked a serological response in the vaccinated animals. All pigs, except those from group F, were positive with nPCR in BAL fluid at D84. The bacterins did not induce a clear overall protection against challenge infection, and there were no significant differences in protective

  6. Making evidence-based selections of influenza vaccines.

    Science.gov (United States)

    Childress, Billy-Clyde; Montney, Joshua D; Albro, Elise A

    2014-01-01

    Years ago, intramuscular influenza vaccines were the only option for those who wanted to arm themselves against the flu. Today there are alternatives, including intradermal injections and intranasal sprays. In order to select the right influenza vaccine for their patients, pharmacists, and other healthcare professionals must have a basic understanding of the immune system. Influenza vaccines elicit different levels of immune response involving innate and adaptive immunity, which are critical to fighting infection. For the 2013-2014 flu season, there were 13 different formulations of influenza vaccines on the market with vast differences in indications, contraindications, and effectiveness. The CDC does not recommend one vaccine over another, but recommends that all patients be vaccinated against the flu. Preventing the spread of influenza is no simple task; however, the most recent evidence on influenza vaccines and sufficient knowledge of the immune system will allow pharmacists and other healthcare providers to better advocate for vaccines, determine which are most appropriate, and ensure their proper administration.

  7. Efficacy of one dose vaccination against experimental infection with two Mycoplasma hyopneumoniae strains.

    Science.gov (United States)

    Michiels, Annelies; Arsenakis, Ioannis; Boyen, Filip; Krejci, Roman; Haesebrouck, Freddy; Maes, Dominiek

    2017-08-29

    Mycoplasma hyopneumoniae (M. hyopneumoniae) is the primary agent of enzootic pneumonia in pigs. Pigs are often infected with different M. hyopneumoniae strains. This study assessed the efficacy of vaccination against experimental infection with two genetically different M. hyopneumoniae strains in weaned piglets. At 33 days of age (D0), 45 M. hyopneumoniae-free piglets were randomly assigned to three different groups: 1) negative control group (NCG; n = 5): not vaccinated, not infected, 2) positive control group (PCG; n = 20): not vaccinated, infected, and 3) vaccination group (VG; n = 20): single vaccination with an inactivated whole-cell M. hyopneumoniae vaccine (Hyogen®, Ceva) (D1), infected. The PCG and VG were endotracheally inoculated with 7 × 10 7 CCU in 7 ml of the highly virulent M. hyopneumoniae strain F7.2C (D24) and 7 × 10 7 CCU in 7 ml low virulent strain F1.12A (D25). A respiratory disease score (RDS) was assessed from D24 until D53. At D53 (euthanasia), macroscopic lung lesions (MLL) were scored, log copies of M. hyopneumoniae DNA (qPCR) and IL-1 and IL-6-concentrations (ELISA) on bronchoalveolar lavage fluid were determined. The RDS and MLL at euthanasia were respectively 0, 1.20 and 0.55 (P hyopneumoniae strain as the vaccinated pigs coughed significantly less, and showed significantly less lung lesions compared to the non-vaccinated challenged pigs: the vaccinated animals showed a 52.9% lower RDS and 91.0% lower MLL compared to the PCG. In the bronchoalveolar lavage fluid collected at the necropsy of the vaccinated pigs, a significantly lower amount of M. hyopneumoniae-DNA and a significantly lower IL-1 and IL-6 concentration was found compared to the pigs of the PCG.

  8. Efficacy, Safety, and Interactions of a Live Infectious Bursal Disease Virus Vaccine for Chickens Based on Strain IBD V877.

    Science.gov (United States)

    Geerligs, Harm J; Ons, Ellen; Boelm, Gert Jan; Vancraeynest, Dieter

    2015-03-01

    Infectious bursal disease (IBD) is a highly contagious disease in young chickens which can result in high morbidity and mortality and also in great economic losses. The main target for the virus is the lymphoid tissue with a special predilection for the bursa of Fabricius. Several vaccines are available to control the disease. Intermediate plus vaccines are used in chickens with high maternal antibody titers which face high infection pressure. An example of an intermediate plus vaccine is a live vaccine based on IBD strain V877. The results of an efficacy study in commercial broilers with different levels of maternally derived antibodies (MDA) showed that the V877-based IBD vaccine can break through maternal antibody titers of higher than 1100 as determined by an IBD ELISA. The safety of the vaccine was demonstrated in a study in which specific-pathogen-free (SPF) chickens were vaccinated with a tenfold dose of the vaccine strain and a tenfold dose of the vaccine strain after five back passages in SPF chickens. The vaccine virus caused lesions, as could be expected for an intermediate plus vaccine, but the scores were not much higher than the maximal scores allowed for mild IBD vaccines in the European Pharmacopoeia, and reversion to virulence was absent. In studies in SPF chickens, there were no negative impacts by the IBD V877 vaccine on the efficacy of a live QX-like IB vaccine and a live Newcastle disease La Sota vaccine in vaccination challenge studies, although the IBD vaccine had a negative effect on the antibody response generated by the QX-like IB vaccine. It is concluded that the IBD V877 vaccine has the capacity to break through high levels of MDA, has a satisfactory safety profile, and interactions with other live vaccines are limited. In order to limit bursal lesions after vaccination it is recommended to confirm the presence of MDA before vaccinating with the V877 vaccine.

  9. Development of fowl cholera vaccine: I. Protection of Pasteurella multocida local isolate vaccine against challenge of homologous and heterologous strains.

    Directory of Open Access Journals (Sweden)

    Supar

    2001-03-01

    Full Text Available Pasteurella multocida locally isolated from chicken and ducks (BCC 299, BCC 2331, DY1, DY2, 12TG, 15TG andimported strains (BCC 1359, 1362; HEDDLESTON group 1 and 6 respectively had been tested for its pathogenicity in theprevious study. The aims of this experiment were to study the preparation of local isolate pasteurellosis vaccines and to determine the protective effect of that vaccines in chicken against the highly pathogenic local isolates of P. multocida. Killed monovalent, bivalent and polyvalent pasteurellosis vaccines were prepared and each was adjunvanted with aluminum hydroxide gel at a final concentration of 1.5% and the cell concentration was equal to the No 10 of MacFarland tube standard. Each of the vaccine prepared was used to vaccinated on a group of six week old of layer chicken (8 per group. Each chicken was subcutaneously injected with 0.2 ml of vaccine, four weeks later each was boostered with similar vaccine with the same dose. Two weeks after giving the boostered vaccine each group of chicken were challenged, half with life bacterium of P. Multocida BCC 2331 and other with DY2. Any chick which survive after challenge was designated as protected by vaccination. Before vaccination 1 ml of blood was drawn from each of chicken and then two weeks apart up to challenge. Serum from each sample was separated and kept in deep freeze until tested by enzyme-linked immunosorbent assay (ELISA. Chicken vaccinated with killed whole cell P. multocida vaccines of monovalent (BCC 2331 or DY2 and bivalent (BCC 2331 + DY2 were protected against challenge with live bacterium of either BCC 2331 or DY2 at rate 67-100%. There was no protection in chicken vaccinated with either BCC 299, DY1, 12TG, 15TG, BCC 1359, or 1362 killed vaccine. Similarly no protection of chicken vaccinated with either DY1 + BCC299, 12TG + 15TG or BCC 1359 + BCC 1362 bivalent vaccines. The protection rate of the polyvalent local isolate vaccine was at average 50-75%. All

  10. Frequency of Adverse Events after Vaccination with Different Vaccinia Strains.

    NARCIS (Netherlands)

    Kretzschmar, Mirjam; Wallinga, Jacco; Teunis, Peter F M; Xing, Shuqin; Mikolajczyk, Rafael

    2006-01-01

    BACKGROUND: Large quantities of smallpox vaccine have been stockpiled to protect entire nations against a possible reintroduction of smallpox. Planning for an appropriate use of these stockpiled vaccines in response to a smallpox outbreak requires a rational assessment of the risks of

  11. Vaccination with Recombinant Cryptococcus Proteins in Glucan Particles Protects Mice against Cryptococcosis in a Manner Dependent upon Mouse Strain and Cryptococcal Species

    Directory of Open Access Journals (Sweden)

    Charles A. Specht

    2017-11-01

    Full Text Available Development of a vaccine to protect against cryptococcosis is a priority given the enormous global burden of disease in at-risk individuals. Using glucan particles (GPs as a delivery system, we previously demonstrated that mice vaccinated with crude Cryptococcus-derived alkaline extracts were protected against lethal challenge with Cryptococcus neoformans and Cryptococcus gattii. The goal of the present study was to identify protective protein antigens that could be used in a subunit vaccine. Using biased and unbiased approaches, six candidate antigens (Cda1, Cda2, Cda3, Fpd1, MP88, and Sod1 were selected, recombinantly expressed in Escherichia coli, purified, and loaded into GPs. Three mouse strains (C57BL/6, BALB/c, and DR4 were then vaccinated with the antigen-laden GPs, following which they received a pulmonary challenge with virulent C. neoformans and C. gattii strains. Four candidate vaccines (GP-Cda1, GP-Cda2, GP-Cda3, and GP-Sod1 afforded a significant survival advantage in at least one mouse model; some vaccine combinations provided added protection over that seen with either antigen alone. Vaccine-mediated protection against C. neoformans did not necessarily predict protection against C. gattii. Vaccinated mice developed pulmonary inflammatory responses that effectively contained the infection; many surviving mice developed sterilizing immunity. Predicted T helper cell epitopes differed between mouse strains and in the degree to which they matched epitopes predicted in humans. Thus, we have discovered cryptococcal proteins that make promising candidate vaccine antigens. Protection varied depending on the mouse strain and cryptococcal species, suggesting that a successful human subunit vaccine will need to contain multiple antigens, including ones that are species specific.

  12. Comparative genomic analysis of Mycobacterium immunogenum strain CD11_6, a new potential vaccine strain against Mycobacterium tuberculosis

    Directory of Open Access Journals (Sweden)

    Atul Munish Chander

    2017-10-01

    The study signifies that Mi strain CD11_6 has sufficient antigenic repertoire that might have led to activate memory T cells against Mtb and causing its eradication. Our further work on this line to validate the role of reported surface membrane proteins may help to know about molecular basis for action of Mi that will improve the present vaccination strategies against Mtb.

  13. Duplex PCR for differentiation of the vaccine strain Brucella suis S2 and B. suis biovar 1 from other strains of Brucella spp.

    Science.gov (United States)

    Nan, Wenlong; Tan, Pengfei; Wang, Yong; Xu, Zouliang; Mao, Kairong; Peng, Daxin; Chen, Yiping

    2014-09-01

    Immunisation with attenuated Brucella spp. vaccines prevents brucellosis, but may also interfere with diagnosis. In this study, a duplex PCR was developed to distinguish Brucella suis vaccine strain S2 from field strains of B. suis biovar 1 and other Brucella spp. The PCR detected 60 fg genomic DNA of B. suis S2 or biovar 1 field strains and was able to distinguish B. suis S2 and wild-type strains of B. suis biovar 1 among 76 field isolates representing all the common species and biovars, as well as four vaccine strains, of Brucella. Copyright © 2014 Elsevier Ltd. All rights reserved.

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

    Science.gov (United States)

    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.

  15. Influence of virus strain and antigen mass on efficacy of H5 avian influenza inactivated vaccines.

    Science.gov (United States)

    Swayne, D E; Beck, J R; Garcia, M; Stone, H D

    1999-06-01

    The influence of vaccine strain and antigen mass on the ability of inactivated avian influenza (AI) viruses to protect chicks from a lethal, highly pathogenic (HP) AI virus challenge was studied. Groups of 4-week-old chickens were immunized with inactivated vaccines containing one of 10 haemagglutinin subtype H5 AI viruses, one heterologous H7 AI virus or normal allantoic fluid (sham), and challenged 3 weeks later by intra-nasal inoculation with a HP H5 chicken-origin AI virus. All 10 H5 vaccines provided good protection from clinical signs and death, and produced positive serological reactions on agar gel immunodiffusion and haemagglutination inhibition tests. In experiment 1, challenge virus was recovered from the oropharynx of 80% of chickens in the H5 vaccine group. In five H5 vaccine groups, challenge virus was not recovered from the cloaca of chickens. In the other five H5 vaccine groups, the number of chickens with detection of challenge virus from the cloaca was lower than in the sham group (P turkey/Wisconsin/68 (H5N9) was the best vaccine candidate of the H5 strains tested (PD50= 0.006 μg AI antigen). These data demonstrate that chickens vaccinated with inactivated H5 whole virus AI vaccines were protected from clinical signs and death, but usage of vaccine generally did not prevent infection by the challenge virus, as indicated by recovery of virus from the oropharynx. Vaccine use reduced cloacal detection rates, and quantity of virus shed from the cloaca and oropharynx in some vaccine groups, which would potentially reduce environmental contamination and disease transmission in the field.

  16. Validation of the Abbreviated Brucella AMOS PCR as a Rapid Screening Method for Differentiation of Brucella abortus Field Strain Isolates and the Vaccine Strains, 19 and RB51

    OpenAIRE

    Ewalt, Darla R.; Bricker, Betsy J.

    2000-01-01

    The Brucella AMOS PCR assay was previously developed to identify and differentiate specific Brucella species. In this study, an abbreviated Brucella AMOS PCR test was evaluated to determine its accuracy in differentiating Brucella abortus into three categories: field strains, vaccine strain 19 (S19), and vaccine strain RB51/parent strain 2308 (S2308). Two hundred thirty-one isolates were identified and tested by the conventional biochemical tests and Brucella AMOS PCR. This included 120 isola...

  17. Correlation of mutations and recombination with growth kinetics of poliovirus vaccine strains.

    Science.gov (United States)

    Pliaka, V; Kyriakopoulou, Z; Tsakogiannis, D; Ruether, I G A; Gartzonika, C; Levidiotou-Stefanou, S; Krikelis, A; Markoulatos, P

    2010-12-01

    Attenuated strains of Sabin poliovirus vaccine replicate in the human gut and, in rare cases, may cause vaccine-associated paralytic poliomyelitis (VAPP). The genetic instability of Sabin strains constitutes one of the main causes of VAPP, a disease that is most frequently associated with type 3 and type 2 Sabin strains, and more rarely with type 1 Sabin strains. In the present study, the growth phenotype of eight oral poliovirus vaccine (OPV) isolates (two non-recombinants and six recombinants), as well as of Sabin vaccine strains, was evaluated using two different assays, the reproductive capacity at different temperatures (Rct) test and the one-step growth curve test in Hep-2 cells at two different temperatures (37°C and 40°C). The growth phenotype of isolates was correlated with genomic modifications in order to identify the determinants and mechanisms of reversion towards neurovirulence. All of the recombinant OPV isolates showed a thermoresistant phenotype in the Rct test. Moreover, both recombinant Sabin-3 isolates showed significantly higher viral yield than Sabin 3 vaccine strain at 37°C and 40°C in the one-step growth curve test. All of the OPV isolates displayed mutations at specific sites of the viral genome, which are associated with the attenuated and temperature-sensitive phenotype of Sabin strains. The results showed that both mutations and recombination events could affect the phenotype traits of Sabin derivatives and may lead to the reversion of vaccinal strains to neurovirulent ones. The use of phenotypic markers along with the genomic analysis may shed additional light on the molecular determinants of the reversed neurovirulent phenotype of Sabin derivatives.

  18. Tuberculosis vaccine strain Mycobacterium bovis BCG Russia is a natural recA mutant

    Directory of Open Access Journals (Sweden)

    Böttger Erik C

    2008-07-01

    Full Text Available Abstract Background The current tuberculosis vaccine is a live vaccine derived from Mycobacterium bovis and attenuated by serial in vitro passaging. All vaccine substrains in use stem from one source, strain Bacille Calmette-Guérin. However, they differ in regions of genomic deletions, antigen expression levels, immunogenicity, and protective efficacy. Results As a RecA phenotype increases genetic stability and may contribute restricting the ongoing evolution of the various BCG substrains while maintaining their protective efficacy, we aimed to inactivate recA by allelic replacement in BCG vaccine strains representing different phylogenetic lineages (Pasteur, Frappier, Denmark, Russia. Homologous gene replacement was achieved successfully in three out of four strains. However, only illegitimate recombination was observed in BCG substrain Russia. Sequence analyses of recA revealed that a single nucleotide insertion in the 5' part of recA led to a translational frameshift with an early stop codon making BCG Russia a natural recA mutant. At the protein level BCG Russia failed to express RecA. Conclusion According to phylogenetic analyses BCG Russia is an ancient vaccine strain most closely related to the parental M. bovis. We hypothesize that recA inactivation in BCG Russia occurred early and is in part responsible for its high degree of genomic stability, resulting in a substrain that has less genetic alterations than other vaccine substrains with respect to M. bovis AF2122/97 wild-type.

  19. Global panel of HIV-1 Env reference strains for standardized assessments of vaccine-elicited neutralizing antibodies.

    Science.gov (United States)

    deCamp, Allan; Hraber, Peter; Bailer, Robert T; Seaman, Michael S; Ochsenbauer, Christina; Kappes, John; Gottardo, Raphael; Edlefsen, Paul; Self, Steve; Tang, Haili; Greene, Kelli; Gao, Hongmei; Daniell, Xiaoju; Sarzotti-Kelsoe, Marcella; Gorny, Miroslaw K; Zolla-Pazner, Susan; LaBranche, Celia C; Mascola, John R; Korber, Bette T; Montefiori, David C

    2014-03-01

    Standardized assessments of HIV-1 vaccine-elicited neutralizing antibody responses are complicated by the genetic and antigenic variability of the viral envelope glycoproteins (Envs). To address these issues, suitable reference strains are needed that are representative of the global epidemic. Several panels have been recommended previously, but no clear answers have been available on how many and which strains are best suited for this purpose. We used a statistical model selection method to identify a global panel of reference Env clones from among 219 Env-pseudotyped viruses assayed in TZM-bl cells with sera from 205 HIV-1-infected individuals. The Envs and sera were sampled globally from diverse geographic locations and represented all major genetic subtypes and circulating recombinant forms of the virus. Assays with a panel size of only nine viruses adequately represented the spectrum of HIV-1 serum neutralizing activity seen with the larger panel of 219 viruses. An optimal panel of nine viruses was selected and augmented with three additional viruses for greater genetic and antigenic coverage. The spectrum of HIV-1 serum neutralizing activity seen with the final 12-virus panel closely approximated the activity seen with subtype-matched viruses. Moreover, the final panel was highly sensitive for detection of many of the known broadly neutralizing antibodies. For broader assay applications, all 12 Env clones were converted to infectious molecular clones using a proviral backbone carrying a Renilla luciferase reporter gene (Env.IMC.LucR viruses). This global panel should facilitate highly standardized assessments of vaccine-elicited neutralizing antibodies across multiple HIV-1 vaccine platforms in different parts of the world. An effective HIV-1 vaccine will need to overcome the extraordinary genetic variability of the virus, where most variation occurs in the viral envelope glycoproteins that are the sole targets for neutralizing antibodies. Efforts to elicit

  20. Effectiveness of Pentavalent Rotavirus Vaccine Against a Diverse Range of Circulating Strains in Nicaragua.

    Science.gov (United States)

    Patel, Manish; Pedreira, Cristina; De Oliveira, Lúcia Helena; Tate, Jacqueline; Leshem, Eyal; Mercado, Juan; Umaña, Jazmina; Balmaceda, Angel; Reyes, Martha; Kerin, Tara; McDonald, Sharla; Gentsch, Jon; Bowen, Michael D; Parashar, Umesh

    2016-05-01

    Because >60 rotavirus strains have been reported worldwide, concerns exist about strain replacement after the introduction of rotavirus vaccines, particularly in developing countries with diverse strains and lower efficacy. We used the case-control design in 4 hospitals in Nicaragua to assess strain-specific vaccine effectiveness (VE) of a pentavalent rotavirus vaccine (RotaTeq) against rotavirus diarrhea. Cases were identified through prospective strain surveillance with reverse transcription-polymerase chain reaction for 3 years among children hospitalized for diarrhea, and controls were children negative for rotavirus. We enrolled 1178 case-patients, 1082 (92%) with G and P typing, and 4927 controls. A different strain predominated each year with increasing age of the vaccine-eligible cohort during the study period: G2P[4] in 2008 (97%; mean age, 11.9 months), G1P[8] in 2009 (55%; mean age, 17.0 months), and G3P[8] in 2010 (78%; mean age, 17.3 months). Overall VE was 45% (95% confidence interval, 25%-59%). Regardless of the strain, VE estimates were 12%-79% lower among children aged ≥12 months relative to those 6-11 months of age. The lower VE for G3P[8] was related to the higher mean age of cases (17.3 months) compared with the G2P[4] strains (11.9 months), with a significant trend (R(2)= 0.819;P< .001) of declining effectiveness with increasing mean age of the cases. Introduction of RotaTeq did not result in sustained emergence of any particular strain in Nicaragua. Variation in strain-specific effectiveness was due to an age-related decline in effectiveness rather than differences in protection against the observed strains. Published by Oxford University Press for the Infectious Diseases Society of America 2016. This work is written by (a) US Government employee(s) and is in the public domain in the US.

  1. Identification of Brucella melitensis Rev.1 vaccine-strain genetic markers: Towards understanding the molecular mechanism behind virulence attenuation.

    Science.gov (United States)

    Issa, Mohammad Nouh; Ashhab, Yaqoub

    2016-09-22

    Brucella melitensis Rev.1 is an avirulent strain that is widely used as a live vaccine to control brucellosis in small ruminants. Although an assembled draft version of Rev.1 genome has been available since 2009, this genome has not been investigated to characterize this important vaccine. In the present work, we used the draft genome of Rev.1 to perform a thorough genomic comparison and sequence analysis to identify and characterize the panel of its unique genetic markers. The draft genome of Rev.1 was compared with genome sequences of 36 different Brucella melitensis strains from the Brucella project of the Broad Institute of MIT and Harvard. The comparative analyses revealed 32 genetic alterations (30 SNPs, 1 single-bp insertion and 1 single-bp deletion) that are exclusively present in the Rev.1 genome. In silico analyses showed that 9 out of the 17 non-synonymous mutations are deleterious. Three ABC transporters are among the disrupted genes that can be linked to virulence attenuation. Out of the 32 mutations, 11 Rev.1 specific markers were selected to test their potential to discriminate Rev.1 using a bi-directional allele-specific PCR assay. Six markers were able to distinguish between Rev.1 and a set of control strains. We succeeded in identifying a panel of 32 genome-specific markers of the B. melitensis Rev.1 vaccine strain. Extensive in silico analysis showed that a considerable number of these mutations could severely affect the function of the associated genes. In addition, some of the discovered markers were able to discriminate Rev.1 strain from a group of control strains using practical PCR tests that can be applied in resource-limited settings. Copyright © 2016 Elsevier Ltd. All rights reserved.

  2. Selection and evaluation of Rhizobial strains of Vigna radiata L ...

    African Journals Online (AJOL)

    STORAGESEVER

    2008-10-20

    Oct 20, 2008 ... Selection and evaluation of Rhizobial strains of Vigna radiata L. beneficial to ... This study aimed to select suitable strains that can be used as inoculants to enhance legume production and simultaneously reduce the use of ... contributor to natural or biological N2 fixation and allows legumes to grow in the ...

  3. Strain diversity plays no major role in the varying efficacy of rotavirus vaccines: an overview.

    Science.gov (United States)

    Velasquez, Daniel E; Parashar, Umesh D; Jiang, Baoming

    2014-12-01

    While a monovalent Rotarix® [RV1] and a pentavalent RotaTeq® [RV5] have been extensively tested and found generally safe and equally efficacious in clinical trials, the question still lingers about the evolving diversity of circulating rotavirus strains over time and their relationship with protective immunity induced by rotavirus vaccines. We reviewed data from clinical trials and observational studies that assessed the efficacy or field effectiveness of rotavirus vaccines against different rotavirus strains worldwide. RV1 provided broad clinical efficacy and field effectiveness against severe diarrhea due to all major circulating strains, including the homotypic G1P[8] and the fully heterotypic G2P[4] strains. Similarly, RV5 provided broad efficacy and effectiveness against RV5 and non-RV5 strains throughout different locations. Rotavirus vaccination provides broad heterotypic protection; however continuing surveillance is needed to track the change of circulating strains and monitor the effectiveness and safety of vaccines. Published by Elsevier B.V.

  4. Clinical development of a novel inactivated poliomyelitis vaccine based on attenuated Sabin poliovirus strains.

    Science.gov (United States)

    Verdijk, Pauline; Rots, Nynke Y; Bakker, Wilfried A M

    2011-05-01

    Following achievement of polio eradication, the routine use of all live-attenuated oral poliovirus vaccines should be discontinued. However, the costs per vaccine dose for the alternative inactivated poliovirus vaccine (IPV) are significantly higher and the current production capacity is not sufficient for worldwide distribution of the vaccine. In order to achieve cost-prize reduction and improve affordability, IPV production processes and dose-sparing strategies should be developed to facilitate local manufacture at a relatively lower cost. The use of attenuated Sabin instead of wild-type polio strains will provide additional safety during vaccine production and permits production in low-cost settings. Sabin-IPV is under development by several manufacturers. This article gives an overview of results from clinical trials with Sabin-IPV and discusses the requirements and challenges in the clinical development of this novel IPV.

  5. Reverse spillover of avian viral vaccine strains from domesticated poultry to wild birds.

    Science.gov (United States)

    Rohaim, M A; El Naggar, R F; Helal, A M; Hussein, H A; Munir, Muhammad

    2017-06-16

    Transmission of viruses from the commercial poultry to wild birds is an emerging paradigm of livestock-wildlife interface. Here, we report the identification and isolation of vaccine strains of avian paramyxovirus serotype 1 (APMV1) and avian coronaviruses (ACoV) from different wild bird species across eight Egyptian governorates between January 2014 and December 2015. Surveillance of avian respiratory viruses in free-ranging wild birds (n=297) identified three species that harboured or excreted APMV1 and ACoVs. Genetic characterization and phylogenetic analysis of recovered viruses revealed a close association with the most widely utilized vaccine strains in the country. These results highlight the potential spillover of vaccine-viruses probably due to extensive use of live-attenuated vaccines in the commercial poultry, and close interaction between domesticated and wild bird populations. Further exploring the full spectrum of vaccine-derived viral vaccine strains in wild birds might help to assess the emergence of future wild-birds origin viruses. Crown Copyright © 2017. Published by Elsevier Ltd. All rights reserved.

  6. Inactive vaccine derived from velogenic strain of local Newcastle disease virus .

    Directory of Open Access Journals (Sweden)

    Darminto

    1996-03-01

    Full Text Available The objective of this research is to evaluate an application of an inactive Newcastle disease (ND vaccine derived from velogenic strain of local Newcastle disease virus (NDV. In this research . the Ira strain of velogenic ND virus was grown in specific pathogen free (SPF eggs and then was inactivated by formalin at a final concentration of 1 :1,000 at 4°C. The inactive antigen was then emulsified with an oil adjuvant or aluminium hydroxide gel before being administered for vaccination in layers and compared to a commercial inactive ND vaccine . Results indicated that application of these inactivated ND vaccines for booster vaccination following vaccination with an active lentogenic ND virus in pullets nearly producing eggs, resulted in high antibody titre which persisted for considerable long period of time and capable of protecting layers from sick of ND and from reducing egg production . Hence, it could be concluded that the inactivated vaccine emulsified in either oil-adjuvant (lanolin-paraffin or aluminium hydroxide gel were considered to be highly immunogenic and capable of protecting layers from sick of ND and from reducing egg production

  7. Genetic and antigenic relationship of foot-and-mouth disease virus serotype O isolates with the vaccine strain O1/BFS.

    Science.gov (United States)

    Xu, Wanhong; Zhang, Zhidong; Nfon, Charles; Yang, Ming

    2018-05-15

    Foot-and-mouth disease serotype O viruses (FMDV/O) are responsible for the most outbreaks in FMD endemic countries. O1/BFS is one of the recommended FMD/O vaccine strains by World Reference Laboratory for FMD. In the current study, FMDV/O1 BFS vaccine strain and serotype O field isolates (45) were analyzed phylogenetically and antigenically to gain more insight into the genetic and antigenic characteristics of the vaccine strain and field isolates. O1/BFS showed similarity with 89% of the field isolates using a virus neutralization test (VNT). The P1 region encoding the FMDV capsid was sequenced and analysed for 46 strains of FMDV/O. Phylogenetic analysis showed these viruses originated from five continents and covered eight of 11 reported topotypes. Five isolates that demonstrated low antigenic similarities with O1/BFS were analyzed for their antigenic variation at the known neutralizing antigenic sites. Three of the five isolates demonstrated unique amino acid substitutions at various antigenic sites. No unique amino acid substitutions were observed for the other two unmatched isolates. Positively selected residues were identified on the surface of the FMD virus capsid supporting that it is important to continuously monitor field isolates for their antigenic and phenotypic changes. In conclusion, the vaccine strain O1/BFS is likely to confer protection against 89% of the 45 FMDV/O isolates based on VNT. Thus O1/BFS vaccine strain is still suitable for use in global FMD serotype O outbreak control. Combining data from phylogenetic, molecular and antigenic analysis can provide improvements in the process of vaccine selection. Crown Copyright © 2018. Published by Elsevier Ltd. All rights reserved.

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

    Science.gov (United States)

    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 ...

  9. Characterization and monitoring of selected rhizobial strains ...

    African Journals Online (AJOL)

    SERVER

    2007-06-18

    Jun 18, 2007 ... Fax: +66-44-216345. fixing symbiosis with bacteria known as rhizobia. ... Rhizobial strains were cultured on Yeast-Malt extract agar contain- ing bromthymol blue ... Colony form-ing was observed every day as well as the ...

  10. Characterization of Brucella abortus mutant strain Δ22915, a potential vaccine candidate.

    Science.gov (United States)

    Bao, Yanqing; Tian, Mingxing; Li, Peng; Liu, Jiameng; Ding, Chan; Yu, Shengqing

    2017-04-04

    Brucellosis, caused by Brucella spp., is an important zoonosis worldwide. Vaccination is an effective strategy for protection against Brucella infection in livestock in developing countries and in wildlife in developed countries. However, current vaccine strains including S19 and RB51 are pathogenic to humans and pregnant animals, limiting their use. In this study, we constructed the Brucella abortus (B. abortus) S2308 mutant strain Δ22915, in which the putative lytic transglycosylase gene BAB_RS22915 was deleted. The biological properties of mutant strain Δ22915 were characterized and protection of mice against virulent S2308 challenge was evaluated. The mutant strain Δ22915 showed reduced survival within RAW264.7 cells and survival in vivo in mice. In addition, the mutant strain Δ22915 failed to escape fusion with lysosomes within host cells, and caused no observable pathological damage. RNA-seq analysis indicated that four genes associated with amino acid/nucleotide transport and metabolism were significantly upregulated in mutant strain Δ22915. Furthermore, inoculation of ∆22915 at 10 5 colony forming units induced effective host immune responses and long-term protection of BALB/c mice. Therefore, mutant strain ∆22915 could be used as a novel vaccine candidate in the future to protect animals against B. abortus infection.

  11. Enhancement of collective immunity in Tokyo metropolitan area by selective vaccination against an emerging influenza pandemic.

    Directory of Open Access Journals (Sweden)

    Masaya M Saito

    Full Text Available Vaccination is a preventive measure against influenza that does not require placing restrictions on social activities. However, since the stockpile of vaccine that can be prepared before the arrival of an emerging pandemic strain is generally quite limited, one has to select priority target groups to which the first stockpile is distributed. In this paper, we study a simulation-based priority target selection method with the goal of enhancing the collective immunity of the whole population. To model the region in which the disease spreads, we consider an urban area composed of suburbs and central areas connected by a single commuter train line. Human activity is modelled following an agent-based approach. The degree to which collective immunity is enhanced is judged by the attack rate in unvaccinated people. The simulation results show that if students and office workers are given exclusive priority in the first three months, the attack rate can be reduced from [Formula: see text] in the baseline case down to 1-2%. In contrast, random vaccination only slightly reduces the attack rate. It should be noted that giving preference to active social groups does not mean sacrificing those at high risk, which corresponds to the elderly in our simulation model. Compared with the random administration of vaccine to all social groups, this design successfully reduces the attack rate across all age groups.

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

    Science.gov (United States)

    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. Copyright © 2015 Elsevier Ltd. All rights reserved.

  13. Human rotavirus strains circulating in Venezuela after vaccine introduction: predominance of G2P[4] and reemergence of G1P[8].

    Science.gov (United States)

    Vizzi, Esmeralda; Piñeros, Oscar A; Oropeza, M Daniela; Naranjo, Laura; Suárez, José A; Fernández, Rixio; Zambrano, José L; Celis, Argelia; Liprandi, Ferdinando

    2017-03-21

    Rotavirus (RV) is the most common cause of severe childhood diarrhea worldwide. Despite Venezuela was among the first developing countries to introduce RV vaccines into their national immunization schedules, RV is still contributing to the burden of diarrhea. Concerns exist about the selective pressure that RV vaccines could exert on the predominant types and/or emergence of new strains. To assess the impact of RV vaccines on the genotype distribution 1 year after the vaccination was implemented, a total of 912 fecal specimens, collected from children with acute gastroenteritis in Caracas from February 2007 to April 2008, were screened, of which 169 (18.5%) were confirmed to be RV positive by PAGE. Rotavirus-associated diarrhea occurred all year-round, although prevailed during the coolest and driest months among unvaccinated children under 24 months old. Of 165 RV strains genotyped for G (VP7) and P (VP4) by seminested multiplex RT-PCR, 77 (46.7%) were G2P[4] and 63 (38.2%) G1P[8]. G9P[8], G3P[8] and G2P[6] were found in a lower proportion (7.3%). Remarkable was also the detection of rotaviruses, but they were rather distant from Rotarix ® vaccine and pre-vaccine strains. Unique amino acid substitutions observed on neutralization domains of the VP7 sequence from Venezuelan post-vaccine G1P[8] could have conditioned their re-emergence and a more efficient dissemination into susceptible population. The results suggest that natural fluctuations of genotypes in combination with forces driving the genetic evolution could determine the spread of novel strains, whose long-term effect on the efficacy of available vaccines should be determined.

  14. Case report: probable transmission of vaccine strain of yellow fever virus to an infant via breast milk

    OpenAIRE

    Kuhn, Susan; Twele-Montecinos, Loreto; MacDonald, Judy; Webster, Patricia; Law, Barbara

    2011-01-01

    The 17D yellow fever vaccine is a live-virus vaccine that has been in use since the 1940s. The incidence of encephalitis after yellow fever vaccination among young infants is much higher than among children older than nine months of age. Until recently, avoidance of vaccination by breastfeeding women who have received yellow fever vaccine had been based on theoretical grounds only. We report the probable transmission of vaccine strain of yellow fever virus from a mother to her infant through ...

  15. Meningococcal factor H binding proteins in epidemic strains from Africa: implications for vaccine development.

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    Rolando Pajon

    2011-09-01

    Full Text Available Factor H binding protein (fHbp is an important antigen for vaccines against meningococcal serogroup B disease. The protein binds human factor H (fH, which enables the bacteria to resist serum bactericidal activity. Little is known about the vaccine-potential of fHbp for control of meningococcal epidemics in Africa, which typically are caused by non-group B strains.We investigated genes encoding fHbp in 106 serogroup A, W-135 and X case isolates from 17 African countries. We determined complement-mediated bactericidal activity of antisera from mice immunized with recombinant fHbp vaccines, or a prototype native outer membrane vesicle (NOMV vaccine from a serogroup B mutant strain with over-expressed fHbp. Eighty-six of the isolates (81% had one of four prevalent fHbp sequence variants, ID 4/5 (serogroup A isolates, 9 (W-135, or 74 (X in variant group 1, or ID 22/23 (W-135 in variant group 2. More than one-third of serogroup A isolates and two-thirds of W-135 isolates tested had low fHbp expression while all X isolates tested had intermediate or high expression. Antisera to the recombinant fHbp vaccines were generally bactericidal only against isolates with fHbp sequence variants that closely matched the respective vaccine ID. Low fHbp expression also contributed to resistance to anti-fHbp bactericidal activity. In contrast to the recombinant vaccines, the NOMV fHbp ID 1 vaccine elicited broad anti-fHbp bactericidal activity, and the antibodies had greater ability to inhibit binding of fH to fHbp than antibodies elicited by the control recombinant fHbp ID 1 vaccine.NOMV vaccines from mutants with increased fHbp expression elicit an antibody repertoire with greater bactericidal activity than recombinant fHbp vaccines. NOMV vaccines are promising for prevention of meningococcal disease in Africa and could be used to supplement coverage conferred by a serogroup A polysaccharide-protein conjugate vaccine recently introduced in some sub

  16. Development and introduction of inactivated poliovirus vaccines derived from Sabin strains in Japan.

    Science.gov (United States)

    Shimizu, Hiroyuki

    2016-04-07

    During the endgame of global polio eradication, the universal introduction of inactivated poliovirus vaccines is urgently required to reduce the risk of vaccine-associated paralytic poliomyelitis and polio outbreaks due to wild and vaccine-derived polioviruses. In particular, the development of inactivated poliovirus vaccines (IPVs) derived from the attenuated Sabin strains is considered to be a highly favorable option for the production of novel IPV that reduce the risk of facility-acquired transmission of poliovirus to the communities. In Japan, Sabin-derived IPVs (sIPVs) have been developed and introduced for routine immunization in November 2012. They are the first licensed sIPVs in the world. Consequently, trivalent oral poliovirus vaccine was used for polio control in Japan for more than half a century but has now been removed from the list of vaccines licensed for routine immunization. This paper reviews the development, introduction, characterization, and global status of IPV derived from attenuated Sabin strains. Copyright © 2014 Elsevier Ltd. All rights reserved.

  17. A rapid minor groove binder PCR method for distinguishing the vaccine strain Brucella abortus 104M.

    Science.gov (United States)

    Nan, Wenlong; Qin, Lide; Wang, Yong; Zhang, Yueyong; Tan, Pengfei; Chen, Yuqi; Mao, Kairong; Chen, Yiping

    2018-01-24

    Brucellosis is a widespread zoonotic disease caused by Gram-negative Brucella bacteria. Immunisation with attenuated vaccine is an effective method of prevention, but it can interfere with diagnosis. Live, attenuated Brucella abortus strain 104M has been used for the prevention of human brucellosis in China since 1965. However, at present, no fast and reliable method exists that can distinguish this strain from field strains. Single nucleotide polymorphism (SNP)-based assays offer a new approach for such discrimination. SNP-based minor groove binder (MGB) and Cycleave assays have been used for rapid identification of four Brucella vaccine strains (B. abortus strains S19, A19 and RB51, and B. melitensis Rev1). The main objective of this study was to develop a PCR assay for rapid and specific detection of strain 104M. We developed a SNP-based MGB PCR assay that could successfully distinguish strain 104M from 18 representative strains of Brucella (B. abortus biovars 1, 2, 3, 4, 5, 6, 7 and 9, B. melitensis biovars 1, 2 and 3, B. suis biovars 1, 2, 3 and 4, B. canis, B. neotomae, and B. ovis), four Brucella vaccine strains (A19, S19, S2, M5), and 55 Brucella clinical field strains. The assay gave a negative reaction with four non-Brucella species (Escherichia coli, Pasteurella multocida, Streptococcus suis and Pseudomonas aeruginosa). The minimum sensitivity of the assay, evaluated using 10-fold dilutions of chromosomal DNA, was 220 fg for the 104M strain and 76 fg for the single non-104M Brucella strain tested (B. abortus A19). The assay was also reproducible (intra- and inter-assay coefficients of variation = 0.006-0.022 and 0.012-0.044, respectively). A SNP-based MGB PCR assay was developed that could straightforwardly and unambiguously distinguish B. abortus vaccine strain 104M from non-104M Brucella strains. Compared to the classical isolation and identification approaches of bacteriology, this real-time PCR assay has substantial advantages in terms of

  18. Immunogenicity and efficacy of Hoshino strain of mumps vaccine in Iran; two years study.

    Science.gov (United States)

    Avijgan, M; Hafizi, M; Moghni, M; Kheiri, S; Esteghamati, A; Sarikhani, S

    2011-06-01

    This report describes the immunogenicity and efficacy and long term immunity of Hoshino strain of Mumps (included in MMR Vaccine) in shahr-e-kord, Islamic Republic of Iran (I.R.Iran). A total of 338 Children aged 3-18 years were tested for Mumps IgG using enzyme-linked immunosorbent assay (ELISA). The proportion of susceptible, mumps IgG negative, children was 19.8% (67 subjects). Of the 67 susceptible children, 36 received the MMR vaccination and successfully completed the study. Blood was collected by venipuncture 3, 12, and 24 months after vaccination and serum samples were tested by ELISA for detection of Mumps IgM and IgG. The overall seroconversion rate was 86.1%, 77.7% and 75% at 3, 12, and 24 months after vaccination respectively.

  19. An objective approach for Burkholderia pseudomallei strain selection as challenge material for medical countermeasures efficacy testing

    Directory of Open Access Journals (Sweden)

    Kristopher E. Van Zandt

    2012-09-01

    Full Text Available Burkholderia pseudomallei is the causative agent of melioidosis, a rare disease of biodefense concern with high mortality and extreme difficulty in treatment. No human vaccines are available that protect against B. pseudomallei infection, and with the current limitations of antibiotic treatment, the development of new preventative and therapeutic interventions is crucial. Although clinical trials could be used to test the efficacy of new medical countermeasures (MCMs, the high mortality rates associated with melioidosis raises significant ethical issues concerning treating individuals with new compounds with unknown efficacies. The US Food and Drug Administration (FDA has formulated a set of guidelines for the licensure of new MCMs to treat diseases in which it would be unethical to test the efficacy of these drugs in humans. The FDA Animal Rule 21 CFR 314 calls for consistent, well-characterized B. pseudomallei strains to be used as challenge material in animal models. In order to facilitate the efficacy testing of new MCMs for melioidosis using animal models, we intend to develop a well-characterized panel of strains for use. This panel will comprise of strains that were isolated from human cases, have a low passage history, are virulent in animal models, and are well characterized phenotypically and genotypically. We have reviewed published and unpublished data on various B. pseudomallei strains to establish an objective method for selecting the strains to be included in the panel of B. pseudomallei strains with attention to five categories: animal infection models, genetic characterization, clinical and passage history, and availability of the strain to the research community. We identified 109 strains with data in at least one of the five categories, scored each strain based on the gathered data and identified 6 strains as candidate for a B. pseudomallei strain panel.

  20. An objective approach for Burkholderia pseudomallei strain selection as challenge material for medical countermeasures efficacy testing.

    Science.gov (United States)

    Van Zandt, Kristopher E; Tuanyok, Apichai; Keim, Paul S; Warren, Richard L; Gelhaus, H Carl

    2012-01-01

    Burkholderia pseudomallei is the causative agent of melioidosis, a rare disease of biodefense concern with high mortality and extreme difficulty in treatment. No human vaccines are available that protect against B. pseudomallei infection, and with the current limitations of antibiotic treatment, the development of new preventative and therapeutic interventions is crucial. Although clinical trials could be used to test the efficacy of new medical countermeasures (MCMs), the high mortality rates associated with melioidosis raises significant ethical issues concerning treating individuals with new compounds with unknown efficacies. The US Food and Drug Administration (FDA) has formulated a set of guidelines for the licensure of new MCMs to treat diseases in which it would be unethical to test the efficacy of these drugs in humans. The FDA "Animal Rule" 21 CFR 314 calls for consistent, well-characterized B. pseudomallei strains to be used as challenge material in animal models. In order to facilitate the efficacy testing of new MCMs for melioidosis using animal models, we intend to develop a well-characterized panel of strains for use. This panel will comprise of strains that were isolated from human cases, have a low passage history, are virulent in animal models, and are well-characterized phenotypically and genotypically. We have reviewed published and unpublished data on various B. pseudomallei strains to establish an objective method for selecting the strains to be included in the panel of B. pseudomallei strains with attention to five categories: animal infection models, genetic characterization, clinical and passage history, and availability of the strain to the research community. We identified 109 strains with data in at least one of the five categories, scored each strain based on the gathered data and identified six strains as candidate for a B. pseudomallei strain panel.

  1. Biological characterization of clones derived from the edmonston strain of measles virus in comparison with schwarz and CAM-70 vaccine strains

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    Maria Beatriz Junqueira Borges

    1996-08-01

    Full Text Available Four virus clones were derived from the Edmonston strain of measles virus by repeated plaque purification. These clones were compared with the vaccine strains Schwarz and CAM-70 in terms of biological activities including plaque formation, hemagglutination, hemolysis and replication in Vero cells and chick embryo fibroblasts (CEF. Two clones of intermediate plaque yielded mixed plaque populations on subcultivation whereas the other two, showing small and large plaque sizes, showed stable plaque phenotypes. The vaccine strains showed consistent homogeneous plaque populations. All the Edmonston clones showed agglutination of monkey erythrocytes in isotonic solution while both vaccine strains hemagglutinated only in the presence of high salt concentrations. Variation in the hemolytic activity was observed among the four clones but no hemolytic activity was detected for the vaccine virus strains. Vaccine strains replicated efficiently both in Vero cells and CEF. All four clones showed efficient replication in Vero cells but different replication profiles in CEF. Two of them replicated efficiently, one was of intermediate efficiency and the other showed no replication in CEF. Two of the clones showed characteristics similar to vaccine strains. One in terms of size and homogeneity of plaques, the other for a low hemolytic activity and both for the efficiency of propagation in CEF.

  2. Selective epidemic vaccination under the performant routing algorithms

    Science.gov (United States)

    Bamaarouf, O.; Alweimine, A. Ould Baba; Rachadi, A.; EZ-Zahraouy, H.

    2018-04-01

    Despite the extensive research on traffic dynamics and epidemic spreading, the effect of the routing algorithms strategies on the traffic-driven epidemic spreading has not received an adequate attention. It is well known that more performant routing algorithm strategies are used to overcome the congestion problem. However, our main result shows unexpectedly that these algorithms favor the virus spreading more than the case where the shortest path based algorithm is used. In this work, we studied the virus spreading in a complex network using the efficient path and the global dynamic routing algorithms as compared to shortest path strategy. Some previous studies have tried to modify the routing rules to limit the virus spreading, but at the expense of reducing the traffic transport efficiency. This work proposed a solution to overcome this drawback by using a selective vaccination procedure instead of a random vaccination used often in the literature. We found that the selective vaccination succeeded in eradicating the virus better than a pure random intervention for the performant routing algorithm strategies.

  3. Vaccination-challenge studies with a Port Chalmers/73 (H3N2)-based swine influenza virus vaccine: Reflections on vaccine strain updates and on the vaccine potency test.

    Science.gov (United States)

    De Vleeschauwer, Annebel; Qiu, Yu; Van Reeth, Kristien

    2015-05-11

    The human A/Port Chalmers/1/73 (H3N2) influenza virus strain, the supposed ancestor of European H3N2 swine influenza viruses (SIVs), was used in most commercial SIV vaccines in Europe until recently. If manufacturers want to update vaccine strains, they have to perform laborious intratracheal (IT) challenge experiments and demonstrate reduced virus titres in the lungs of vaccinated pigs. We aimed to examine (a) the ability of a Port Chalmers/73-based commercial vaccine to induce cross-protection against a contemporary European H3N2 SIV and serologic cross-reaction against H3N2 SIVs from Europe and North America and (b) the validity of intranasal (IN) challenge and virus titrations of nasal swabs as alternatives for IT challenge and titrations of lung tissue in vaccine potency tests. Pigs were vaccinated with Suvaxyn Flu(®) and challenged by the IT or IN route with sw/Gent/172/08. Post-vaccination sera were examined in haemagglutination-inhibition assays against vaccine and challenge strains and additional H3N2 SIVs from Europe and North America, including an H3N2 variant virus. Tissues of the respiratory tract and nasal swabs were collected 3 days post challenge (DPCh) and from 0-7 DPCh, respectively, and examined by virus titration. Two vaccinations consistently induced cross-reactive antibodies against European H3N2 SIVs from 1998-2012, but minimal or undetectable antibody titres against North American viruses. Challenge virus titres in the lungs, trachea and nasal mucosa of the vaccinated pigs were significantly reduced after both IT and IN challenge. Yet the reduction of virus titres and nasal shedding was greater after IT challenge. The Port Chalmers/73-based vaccine still offered protection against a European H3N2 SIV isolated 35 years later and with only 86.9% amino acid homology in its HA1, but it is unlikely to protect against H3N2 SIVs that are endemic in North America. We use our data to reflect on vaccine strain updates and on the vaccine potency test

  4. Evaluation of Lactobacillus strains for selected probiotic properties.

    Science.gov (United States)

    Turková, Kristýna; Mavrič, Anja; Narat, Mojca; Rittich, Bohuslav; Spanová, Alena; Rogelj, Irena; Matijašić, Bojana Bogovič

    2013-07-01

    Eleven strains of Lactobacillus collected in the Culture Collection of Dairy Microorganisms (CCDM) were evaluated for selected probiotic properties such as survival in gastrointestinal fluids, antimicrobial activity, and competition with non-toxigenic Escherichia coli O157:H7 for adhesion on Caco-2 cells. The viable count of lactobacilli was reduced during 3-h incubation in gastric fluid followed by 3-h incubation in intestinal fluid. All strains showed antimicrobial activity and the three most effective strains inhibited the growth of at least 16 indicator strains. Antimicrobial metabolites of seven strains active against Lactobacillus and Clostridium indicator strains were found to be sensitive to proteinase K and trypsin, which indicates their proteinaceous nature. The degree of competitive inhibition of non-toxigenic E. coli O157:H7 adhesion on the surface of Caco-2 cells was strain-dependent. A significant decrease (P strains were selected for additional studies of antimicrobial activity, i.e., Lactobacillus gasseri CCDM 215, Lactobacillus acidophilus CCDM 149, and Lactobacillus helveticus CCDM 82.

  5. New Strains Intended for the Production of Inactivated Polio Vaccine at Low-Containment After Eradication.

    Directory of Open Access Journals (Sweden)

    Sarah Knowlson

    2015-12-01

    Full Text Available Poliomyelitis has nearly been eradicated through the efforts of the World Health Organization's Global Eradication Initiative raising questions on containment of the virus after it has been eliminated in the wild. Most manufacture of inactivated polio vaccines currently requires the growth of large amounts of highly virulent poliovirus, and release from a production facility after eradication could be disastrous; WHO have therefore recommended the use of the attenuated Sabin strains for production as a safer option although it is recognised that they can revert to a transmissible paralytic form. We have exploited the understanding of the molecular virology of the Sabin vaccine strains to design viruses that are extremely genetically stable and hyperattenuated. The viruses are based on the type 3 Sabin vaccine strain and have been genetically modified in domain V of the 5' non-coding region by changing base pairs to produce a cassette into which capsid regions of other serotypes have been introduced. The viruses give satisfactory yields of antigenically and immunogenically correct viruses in culture, are without measurable neurovirulence and fail to infect non-human primates under conditions where the Sabin strains will do so.

  6. New Strains Intended for the Production of Inactivated Polio Vaccine at Low-Containment After Eradication.

    Science.gov (United States)

    Knowlson, Sarah; Burlison, John; Giles, Elaine; Fox, Helen; Macadam, Andrew J; Minor, Philip D

    2015-12-01

    Poliomyelitis has nearly been eradicated through the efforts of the World Health Organization's Global Eradication Initiative raising questions on containment of the virus after it has been eliminated in the wild. Most manufacture of inactivated polio vaccines currently requires the growth of large amounts of highly virulent poliovirus, and release from a production facility after eradication could be disastrous; WHO have therefore recommended the use of the attenuated Sabin strains for production as a safer option although it is recognised that they can revert to a transmissible paralytic form. We have exploited the understanding of the molecular virology of the Sabin vaccine strains to design viruses that are extremely genetically stable and hyperattenuated. The viruses are based on the type 3 Sabin vaccine strain and have been genetically modified in domain V of the 5' non-coding region by changing base pairs to produce a cassette into which capsid regions of other serotypes have been introduced. The viruses give satisfactory yields of antigenically and immunogenically correct viruses in culture, are without measurable neurovirulence and fail to infect non-human primates under conditions where the Sabin strains will do so.

  7. Vaccination reduces macrophage infiltration in bronchus-associated lymphoid tissue in pigs infected with a highly virulent Mycoplasma hyopneumoniae strain

    Directory of Open Access Journals (Sweden)

    Vranckx Katleen

    2012-03-01

    Full Text Available Abstract Background Mycoplasma hyopneumoniae is the causative agent of enzootic pneumonia and is responsible for significant economic losses to the pig industry. To better understand the mode of action of a commercial, adjuvanted, inactivated whole cell vaccine and the influence of diversity on the efficacy of vaccination, we investigated samples from vaccinated and non-vaccinated pigs experimentally infected with either a low (LV or a highly virulent (HV M. hyopneumoniae strain. Non-vaccinated and sham-infected control groups were included. Lung tissue samples collected at 4 and 8 weeks post infection (PI were immunohistochemically tested for the presence of T-lymphocytes, B-lymphocytes and macrophages in the bronchus-associated lymphoid tissue (BALT. The number of M. hyopneumoniae organisms in bronchoalveolar lavage (BAL fluid was determined using quantitative PCR at 4 and 8 weeks PI. Serum antibodies against M. hyopneumoniae were determined at 0, 2, 4, 6 and 8 weeks PI. Results The immunostaining revealed a lower density of macrophages in the BALT of the vaccinated groups compared to the non-vaccinated groups. The highest number of M. hyopneumoniae organisms in the BAL fluid was measured at 4 weeks PI for the HV strain and at 8 weeks PI for the LV strain. Vaccination reduced the number of organisms non-significantly, though for the HV strain the reduction was clinically more relevant than for the LV strain. At the level of the individual pigs, a higher lung lesion score was associated with more M. hyopneumoniae organisms in the lungs and a higher density of the investigated immune cells in the BALT. Conclusions In conclusion, the infiltration of macrophages after infection with M. hyopneumoniae is reduced by vaccination. The M. hyopneumoniae replication in the lungs is also reduced in vaccinated pigs, though the HV strain is inhibited more than the LV strain.

  8. ACAM2000 clonal Vero cell culture vaccinia virus (New York City Board of Health strain)--a second-generation smallpox vaccine for biological defense.

    Science.gov (United States)

    Monath, Thomas P; Caldwell, Joseph R; Mundt, Wolfgang; Fusco, Joan; Johnson, Casey S; Buller, Mark; Liu, Jian; Gardner, Bridget; Downing, Greg; Blum, Paul S; Kemp, Tracy; Nichols, Richard; Weltzin, Richard

    2004-10-01

    The threat of smallpox as a biological weapon has spurred efforts to create stockpiles of vaccine for emergency preparedness. In lieu of preparing vaccine in animal skin (the original method), we cloned vaccinia virus (New York City Board of Health strain, Dryvax by plaque purification and amplified the clone in cell culture. The overarching goal was to produce a modern vaccine that was equivalent to the currently licensed Dryvax in its preclinical and clinical properties, and could thus reliably protect humans against smallpox. A variety of clones were evaluated, and many were unacceptably virulent in animal models. One clonal virus (ACAM1000) was selected and produced at clinical grade in MRC-5 human diploid cells. ACAM1000 was comparable to Dryvax in immunogenicity and protective activity but was less neurovirulent for mice and nonhuman primates. To meet requirements for large quantities of vaccine after the events of September 11th 2001, the ACAM1000 master virus seed was used to prepare vaccine (designated ACAM2000) at large scale in Vero cells under serum-free conditions. The genomes of ACAM1000 and ACAM2000 had identical nucleotide sequences, and the vaccines had comparable biological phenotypes. ACAM1000 and ACAM2000 were evaluated in three Phase 1 clinical trials. The vaccines produced major cutaneous reactions and evoked neutralizing antibody and cell-mediated immune responses in the vast majority of subjects and had a reactogenicity profile similar to that of Dryvax.

  9. Characterization of Selected Lactobacillus Strains for Use as Probiotics

    OpenAIRE

    Song, Minyu; Yun, Bohyun; Moon, Jae-Hak; Park, Dong-June; Lim, Kwangsei; Oh, Sejong

    2015-01-01

    The aim of this study was to evaluate the functional properties of lactic acid bacteria from various sources and to identify strains for use as probiotics. Ten Lactobacillus strains were selected and their properties such as bile tolerance, acid resistance, cholesterol assimilation activity, and adherence to HT-29 cells were assessed to determine their potential as probiotics. Lactobacillus sp. JNU 8829, L. casei MB3, L. sakei MA9, L. sakei CH8, and L. acidophilus M23 were found to show full ...

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

    Science.gov (United States)

    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

  11. Evaluation of antigens stability of tobacco seeds as edible vaccine against VTEC strains

    Directory of Open Access Journals (Sweden)

    Luciana Rossi

    2015-11-01

    Full Text Available Plants have represent a promising alternative for biopharmaceutical proteins (Ma et al., 2003; Rossi et al., 2014. Many plant based edible vaccines have been shown to be effective in inducing local immune responses (Rossi et al., 2013. Edible vaccines can activate both mucosal and systemic immunity, as they come in contact with the digestive tract lining. This dual effect would provide first-line defense against pathogens invading through the mucosa. The antigens are released in the intestines are taken up by M cells that are present over the Payer’s patches (in the ileum and the gut associated lymphoid tissue (GALT. Edible vaccines represent an important worldwide goal for the prevention of the enteric diseases, also in livestock. In particular, the enteric infections are a significant clinical problem in pigs. Verocytotoxic Escherichia (E. coli strains are responsible for serious enterotoxaemia that causes important economic losses in the pig industry. The production of a vaccine for oral administration of transgenic seeds could be a practical and efficient system to prevent the infection and to reduce the antibiotic use. This study was focused on tobacco plants, previously transformed by agroinfection for the seed-specific expression of antigenic proteins (F18 adhesive fimbriae and the B subunit of the Vt2e toxin as model of edible vaccines against verocytotoxic E. coli strains. The dietary administration of transgenic tobacco seeds promotes a significant increase in the number of mucosal IgA-producing cells of the tunica propria in both small and large intestine in mice (Rossi et al., 2013. A protective effect of oral administration of transgenic tobacco seeds was also observed against verocytotoxic Escherichia coli infection in piglets (Rossi et al., 2014. The aim of this study was to assess the seed-expression stability, that is a important requirement in the vaccine production, of F 18 and Vt2e-B heterologous genes into the progeny of

  12. A national reference for inactivated polio vaccine derived from Sabin strains in Japan.

    Science.gov (United States)

    Shirato, Haruko; Someya, Yuichi; Ochiai, Masaki; Horiuchi, Yoshinobu; Takahashi, Motohide; Takeda, Naokazu; Wakabayashi, Kengo; Ouchi, Yasumitsu; Ota, Yoshihiro; Tano, Yoshio; Abe, Shinobu; Yamazaki, Shudo; Wakita, Takaji

    2014-09-08

    As one aspect of its campaign to eradicate poliomyelitis, the World Health Organization (WHO) has encouraged development of the inactivated polio vaccine (IPV) derived from the Sabin strains (sIPV) as an option for an affordable polio vaccine, especially in low-income countries. The Japan Poliomyelitis Research Institute (JPRI) inactivated three serotypes of the Sabin strains and made sIPV preparations, including serotypes 1, 2 and 3 D-antigens in the ratio of 3:100:100. The National Institute of Infectious Diseases, Japan, assessed the immunogenic stability of these sIPV preparations in a rat potency test, according to an evaluation method recommended by the WHO. The immunogenicity of the three serotypes was maintained for at least 4 years when properly stored under -70°C. Based on these data, the sIPV preparations made by JPRI have been approved as national reference vaccines by the Japanese national control authority and used for the quality control of the tetracomponent sIPV-containing diphtheria-tetanus-acellular pertussis combination vaccines that were licensed for a routine polio immunization in Japan. Copyright © 2014 Elsevier Ltd. All rights reserved.

  13. Complete Genome Sequence of the Goatpox Virus Strain Gorgan Obtained Directly from a Commercial Live Attenuated Vaccine

    Science.gov (United States)

    Mathijs, Elisabeth; Vandenbussche, Frank; Haegeman, Andy; Al-Majali, Ahmad; De Clercq, Kris

    2016-01-01

    This is a report of the complete genome sequence of the goatpox virus strain Gorgan, which was obtained directly from a commercial live attenuated vaccine (Caprivac, Jordan Bio-Industries Centre). PMID:27738031

  14. Microbial compositional changes in broiler chicken cecal contents from birds challenged with different Salmonella vaccine candidate strains.

    Science.gov (United States)

    Park, Si Hong; Kim, Sun Ae; Rubinelli, Peter M; Roto, Stephanie M; Ricke, Steven C

    2017-05-31

    Previously, we constructed and characterized the vaccine efficacy of Salmonella Typhimurium mutant strains in poultry with either inducible mviN expression (P BAD -mviN) or methionine auxotrophy (ΔΔmetRmetD). The aim of the present study was to assess potential impact of these Salmonella vaccine strains on the cecal microbiota using a next generation sequencing (NGS). The cecal microbial community obtained from unvaccinated (group 1) and vaccinated chickens (group 2, vaccinated with P BAD -mviN; group 3, vaccinated with wild type; group 4, vaccinated with ΔΔmetRmetD) were subjected to microbiome sequencing analysis with an Illumina MiSeq platform. The NGS microbiome analysis of chicken ceca revealed considerable changes in microbial composition in the presence of the different vaccine strains and exhibited detectable patterns of distinctive clustering among the respective groups (the R value of unweighted PCoA plot was 0.68). The present study indicates that different S. Typhimurium vaccine strains can differentially influence the microbiota of the ceca in terms of presence but not in the relative abundance of microbiota. Copyright © 2017 Elsevier Ltd. All rights reserved.

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

    Science.gov (United States)

    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. © 2016 The Author(s).

  16. Characterization of Selected Lactobacillus Strains for Use as Probiotics.

    Science.gov (United States)

    Song, Minyu; Yun, Bohyun; Moon, Jae-Hak; Park, Dong-June; Lim, Kwangsei; Oh, Sejong

    2015-01-01

    The aim of this study was to evaluate the functional properties of lactic acid bacteria from various sources and to identify strains for use as probiotics. Ten Lactobacillus strains were selected and their properties such as bile tolerance, acid resistance, cholesterol assimilation activity, and adherence to HT-29 cells were assessed to determine their potential as probiotics. Lactobacillus sp. JNU 8829, L. casei MB3, L. sakei MA9, L. sakei CH8, and L. acidophilus M23 were found to show full tolerance to the 0.3% bile acid. All strains without L. acidophilus M23 were the most acid-tolerant strains. After incubating the strains at pH 2.5 for 2 h, their viability decreased by 3 Log cells. Some strains survived at pH 2.5 in the presence of pepsin and 0.3% bile acid. Lactobacillus sp. JNU 8829, L. acidophilus KU41, L. acidophilus M23, L. fermentum NS2, L. plantarum M13, and L. plantarum NS3 were found to reduce cholesterol levels by >50% in vitro. In the adhesion assay, Lactobacillus sp. JNU 8829, L. casei MB3, L. sakei MA9, and L. sakei CH8 showed higher adhesion activities after 2 h of co-incubation with the intestinal cells. The results of this comprehensive analysis shows that this new probiotic strain named, Lactobacillus sp. JNU 8829 could be a promising candidate for dairy products.

  17. Genomic sequence and virulence of clonal isolates of vaccinia virus Tiantan, the Chinese smallpox vaccine strain.

    Directory of Open Access Journals (Sweden)

    Qicheng Zhang

    Full Text Available Despite the worldwide eradication of smallpox in 1979, the potential bioterrorism threat from variola virus and the ongoing use of vaccinia virus (VACV as a vector for vaccine development argue for continued research on VACV. In China, the VACV Tiantan strain (TT was used in the smallpox eradication campaign. Its progeny strain is currently being used to develop a human immunodeficiency virus (HIV vaccine. Here we sequenced the full genomes of five TT clones isolated by plaque purification from the TT (752-1 viral stock. Phylogenetic analysis with other commonly used VACV strains showed that TT (752-1 and its clones clustered and exhibited higher sequence diversity than that found in Dryvax clones. The ∼190 kbp genomes of TT appeared to encode 273 open reading frames (ORFs. ORFs located in the middle of the genome were more conserved than those located at the two termini, where many virulence and immunomodulation associated genes reside. Several patterns of nucleotide changes including point mutations, insertions and deletions were identified. The polymorphisms in seven virulence-associated proteins and six immunomodulation-related proteins were analyzed. We also investigated the neuro- and skin- virulence of TT clones in mice and rabbits, respectively. The TT clones exhibited significantly less virulence than the New York City Board of Health (NYCBH strain, as evidenced by less extensive weight loss and morbidity in mice as well as produced smaller skin lesions and lower incidence of putrescence in rabbits. The complete genome sequences, ORF annotations, and phenotypic diversity yielded from this study aid our understanding of the Chinese historic TT strain and are useful for HIV vaccine projects employing TT as a vector.

  18. Genomic sequence and virulence of clonal isolates of vaccinia virus Tiantan, the Chinese smallpox vaccine strain.

    Science.gov (United States)

    Zhang, Qicheng; Tian, Meijuan; Feng, Yi; Zhao, Kai; Xu, Jing; Liu, Ying; Shao, Yiming

    2013-01-01

    Despite the worldwide eradication of smallpox in 1979, the potential bioterrorism threat from variola virus and the ongoing use of vaccinia virus (VACV) as a vector for vaccine development argue for continued research on VACV. In China, the VACV Tiantan strain (TT) was used in the smallpox eradication campaign. Its progeny strain is currently being used to develop a human immunodeficiency virus (HIV) vaccine. Here we sequenced the full genomes of five TT clones isolated by plaque purification from the TT (752-1) viral stock. Phylogenetic analysis with other commonly used VACV strains showed that TT (752-1) and its clones clustered and exhibited higher sequence diversity than that found in Dryvax clones. The ∼190 kbp genomes of TT appeared to encode 273 open reading frames (ORFs). ORFs located in the middle of the genome were more conserved than those located at the two termini, where many virulence and immunomodulation associated genes reside. Several patterns of nucleotide changes including point mutations, insertions and deletions were identified. The polymorphisms in seven virulence-associated proteins and six immunomodulation-related proteins were analyzed. We also investigated the neuro- and skin- virulence of TT clones in mice and rabbits, respectively. The TT clones exhibited significantly less virulence than the New York City Board of Health (NYCBH) strain, as evidenced by less extensive weight loss and morbidity in mice as well as produced smaller skin lesions and lower incidence of putrescence in rabbits. The complete genome sequences, ORF annotations, and phenotypic diversity yielded from this study aid our understanding of the Chinese historic TT strain and are useful for HIV vaccine projects employing TT as a vector.

  19. Sequence analysis of measles virus strains collected during the pre- and early-vaccination era in Denmark reveals a considerable diversity of ancient strains

    DEFF Research Database (Denmark)

    Christensen, Laurids Siig; Schöller, S.; Schierup, M. H.

    2002-01-01

    A total of 199 serum samples from patients with measles collected in Denmark, Greenland and the Faroe Islands from 1964 to 1983 were analysed by PCR. Measles virus (MV) RNA could be detected in 38 (19%) of the samples and a total of 18 strains were subjected to partial sequence analysis of the he......A total of 199 serum samples from patients with measles collected in Denmark, Greenland and the Faroe Islands from 1964 to 1983 were analysed by PCR. Measles virus (MV) RNA could be detected in 38 (19%) of the samples and a total of 18 strains were subjected to partial sequence analysis...... of the hemagglutinin gene. The strains exhibited a considerable genomic diversity, which is at odds with the assumption that one genome type prevailed among globally circulating MV strains prior to the advent of live-attenuated vaccines. Our data indicate that the similarity of the various vaccine strains...... is attributed to their having originated from the same primary isolate. Consequently, it is implied that a small number of clinical manifestations of MV worldwide from which strains similar to the vaccine strain were identified were vaccine related rather than being caused by members of a persistently...

  20. Temporal association between the isolation of Sabin-related poliovirus vaccine strains and the Guillain-Barré syndrome

    Directory of Open Access Journals (Sweden)

    F. Friedrich

    1996-02-01

    Full Text Available Thirty eight paralysis cases classified as Guillain-Barré syndrome (GBS in Brazil were analysed. In all these cases Sabin-related poliovirus vaccine strains were isolated. In most of the cases the last vaccine dose was given months or years before the onset of GBS, suggesting a persistent infection or the transmission of the Sabin-related strains to the patients. The isolation of Sabin-related strains from GBS cases some days or weeks after the onset of the disease, demonstrated a temporal association between the isolation of the strains and the disease. Although the isolates from the GBS cases may not be the etiological agent of the disease, this study strongly indicates that infections caused by Sabin-related vaccine strains can trigger the GBS in certain cases.

  1. Development and Regulation of Novel Influenza Virus Vaccines: A United States Young Scientist Perspective.

    Science.gov (United States)

    Khurana, Surender

    2018-04-27

    Vaccination against influenza is the most effective approach for reducing influenza morbidity and mortality. However, influenza vaccines are unique among all licensed vaccines as they are updated and administered annually to antigenically match the vaccine strains and currently circulating influenza strains. Vaccine efficacy of each selected influenza virus vaccine varies depending on the antigenic match between circulating strains and vaccine strains, as well as the age and health status of the vaccine recipient. Low vaccine effectiveness of seasonal influenza vaccines in recent years provides an impetus to improve current seasonal influenza vaccines, and for development of next-generation influenza vaccines that can provide broader, long-lasting protection against both matching and antigenically diverse influenza strains. This review discusses a perspective on some of the issues and formidable challenges facing the development and regulation of the next-generation influenza vaccines.

  2. Unique Safety Issues Associated with Virus Vectored Vaccines: Potential for and Theoretical Consequences of Recombination with Wild Type Virus Strains

    Science.gov (United States)

    Condit, Richard C.; Williamson, Anna-Lise; Sheets, Rebecca; Seligman, Stephen J.; Monath, Thomas P.; Excler, Jean-Louis; Gurwith, Marc; Bok, Karin; Robertson, James S.; Kim, Denny; Hendry, Michael; Singh, Vidisha; Mac, Lisa M.; Chen, Robert T.

    2016-01-01

    In 2003 and 2013, the World Health Organization convened informal consultations on characterization and quality aspects of vaccines based on live virus vectors. In the resulting reports, one of several issues raised for future study was the potential for recombination of virus-vectored vaccines with wild type pathogenic virus strains. This paper presents an assessment of this issue formulated by the Brighton Collaboration. To provide an appropriate context for understanding the potential for recombination of virus-vectored vaccines, we review briefly the current status of virus vectored vaccines, mechanisms of recombination between viruses, experience with recombination involving live attenuated vaccines in the field, and concerns raised previously in the literature regarding recombination of virus-vectored vaccines with wild type virus strains. We then present a discussion of the major variables that could influence recombination between a virus-vectored vaccine and circulating wild type virus and the consequences of such recombination, including intrinsic recombination properties of the parent virus used as a vector; sequence relatedness of vector and wild virus; virus host range, pathogenesis and transmission; replication competency of vector in target host; mechanism of vector attenuation; additional factors potentially affecting virulence; and circulation of multiple recombinant vectors in the same target population. Finally, we present some guiding principles for vector design and testing intended to anticipate and mitigate the potential for and consequences of recombination of virus-vectored vaccines with wild type pathogenic virus strains. PMID:27346303

  3. Comparative immunological evaluation of recombinant Salmonella Typhimurium strains expressing model antigens as live oral vaccines.

    Science.gov (United States)

    Zheng, Song-yue; Yu, Bin; Zhang, Ke; Chen, Min; Hua, Yan-Hong; Yuan, Shuofeng; Watt, Rory M; Zheng, Bo-Jian; Yuen, Kwok-Yung; Huang, Jian-Dong

    2012-09-26

    Despite the development of various systems to generate live recombinant Salmonella Typhimurium vaccine strains, little work has been performed to systematically evaluate and compare their relative immunogenicity. Such information would provide invaluable guidance for the future rational design of live recombinant Salmonella oral vaccines. To compare vaccine strains encoded with different antigen delivery and expression strategies, a series of recombinant Salmonella Typhimurium strains were constructed that expressed either the enhanced green fluorescent protein (EGFP) or a fragment of the hemagglutinin (HA) protein from the H5N1 influenza virus, as model antigens. The antigens were expressed from the chromosome, from high or low-copy plasmids, or encoded on a eukaryotic expression plasmid. Antigens were targeted for expression in either the cytoplasm or the outer membrane. Combinations of strategies were employed to evaluate the efficacy of combined delivery/expression approaches. After investigating in vitro and in vivo antigen expression, growth and infection abilities; the immunogenicity of the constructed recombinant Salmonella strains was evaluated in mice. Using the soluble model antigen EGFP, our results indicated that vaccine strains with high and stable antigen expression exhibited high B cell responses, whilst eukaryotic expression or colonization with good construct stability was critical for T cell responses. For the insoluble model antigen HA, an outer membrane expression strategy induced better B cell and T cell responses than a cytoplasmic strategy. Most notably, the combination of two different expression strategies did not increase the immune response elicited. Through systematically evaluating and comparing the immunogenicity of the constructed recombinant Salmonella strains in mice, we identified their respective advantages and deleterious or synergistic effects. Different construction strategies were optimally-required for soluble versus

  4. Monitoring of canine parvovirus (CPV) strains detected in vaccinated puppies in Brazil.

    Science.gov (United States)

    Castro, T X; Costa, E M; Leite, J P; Labarthe, N V; Cubel Garcia, R C N

    2011-04-01

    The objective of this study was to investigate, by partial sequencing of VP2 protein, the variability of CPV detected in 37 fecal samples collected from vaccinated puppies with enteritis. Laboratorial diagnosis of CPV was confirmed by HA/HI and PCR and, for sequencing analyses, two different regions of the VP2 gene were amplified by PCR. From 1995 to 2004, all strains were characterized as CPV-2a. After that, both CPV-2a and CPV-2b were detected. All CPV-2a showed a non-synonymous mutation in the residue 297 (Ser→Ala). A synonymous substitution at the AA 574 was also observed in 15/37 samples. Our findings indicate that the cases of vaccine failure are most likely not associated to the mutations detected in the sequenced regions. However, the monitoring of genotyping mutations that led to new CPV strains is essential to determinate if current vaccines will keep providing protection against all new future variants. Copyright © 2010 Elsevier Ltd. All rights reserved.

  5. Rotavirus Strain Trends During the Postlicensure Vaccine Era: United States, 2008–2013

    Science.gov (United States)

    Bowen, Michael D.; Mijatovic-Rustempasic, Slavica; Esona, Mathew D.; Teel, Elizabeth N.; Gautam, Rashi; Sturgeon, Michele; Azimi, Parvin H.; Baker, Carol J.; Bernstein, David I.; Boom, Julie A.; Chappell, James; Donauer, Stephanie; Edwards, Kathryn M.; Englund, Janet A.; Halasa, Natasha B.; Harrison, Christopher J.; Johnston, Samantha H.; Klein, Eileen J.; McNeal, Monica M.; Moffatt, Mary E.; Rench, Marcia A.; Sahni, Leila C.; Selvarangan, Rangaraj; Staat, Mary A.; Szilagyi, Peter G.; Weinberg, Geoffrey A.; Wikswo, Mary E.; Parashar, Umesh D.; Payne, Daniel C.

    2016-01-01

    Background Group A rotaviruses (RVA) are a significant cause of pediatric gastroenteritis worldwide. The New Vaccine Surveillance Network (NVSN) has conducted active surveillance for RVA at pediatric hospitals and emergency departments at 3–7 geographically diverse sites in the United States since 2006. Methods Over 6 consecutive years, from 2008 to 2013, 1523 samples from NVSN sites that were tested positive by a Rotaclone enzyme immunoassay were submitted to the Centers for Disease Control and Prevention for genotyping. Results In the 2009, 2010, and 2011 seasons, genotype G3P[8] was the predominant genotype throughout the network, with a 46%–84% prevalence. In the 2012 season, G12P[8] replaced G3P[8] as the most common genotype, with a 70% prevalence, and this trend persisted in 2013 (68.0% prevalence). Vaccine (RotaTeq; Rotarix) strains were detected in 0.6%–3.4% of genotyped samples each season. Uncommon and unusual strains (eg, G8P[4], G3P[24], G2P[8], G3P[4], G3P[6], G24P[14], G4P[6], and G9P[4]) were detected sporadically over the study period. Year, study site, and race were found to be significant predictors of genotype. Conclusions Continued active surveillance is needed to monitor RVA genotypes in the United States and to detect potential changes since vaccine licensure. PMID:27302190

  6. Characterization of field isolates of Suid herpesvirus 1 (Aujeszky's disease virus) as derivatives of attenuated vaccine strains

    DEFF Research Database (Denmark)

    Christensen, Laurids Siig; Medveczky, I.; Strandbygaard, Bertel

    1992-01-01

    Field isolates of suid herpesvirus 1 (Aujeszky's disease virus) from Poland and Hungary were identified by restriction fragment pattern analysis as derivatives of attenuated vaccine strains. The Polish isolates were found to be related to the BUK-TK-900 strain (Suivac A) which is widely used...

  7. Antigen sparing with adjuvanted inactivated polio vaccine based on Sabin strains.

    Science.gov (United States)

    Westdijk, Janny; Koedam, Patrick; Barro, Mario; Steil, Benjamin P; Collin, Nicolas; Vedvick, Thomas S; Bakker, Wilfried A M; van der Ley, Peter; Kersten, Gideon

    2013-02-18

    Six different adjuvants, each in combination with inactivated polio vaccine (IPV) produced with attenuated Sabin strains (sIPV), were evaluated for their ability to enhance virus neutralizing antibody titres (VNTs) in the rat potency model. The increase of VNTs was on average 3-, 15-, 24-fold with adjuvants after one immunization (serotypes 1, 2, and 3, respectively). Also after a boost immunization the VNTs of adjuvanted sIPV were on average another 7-20-27 times higher than after two inoculations of sIPV without adjuvant. The results indicate that it is feasible to increase the potency of inactivated polio vaccines by using adjuvants. Copyright © 2013 Elsevier Ltd. All rights reserved.

  8. Risk analysis of inter-species reassortment through a Rift Valley fever phlebovirus MP-12 vaccine strain.

    Directory of Open Access Journals (Sweden)

    Hoai J Ly

    Full Text Available Rift Valley fever (RVF is a mosquito-borne zoonotic disease endemic to Africa and the Arabian Peninsula. The causative agent, Rift Valley fever phlebovirus (RVFV, belongs to the genus Phlebovirus in the family Phenuiviridae and causes high rates of abortions in ruminants, and hemorrhagic fever, encephalitis, or blindness in humans. Viral maintenance by mosquito vectors has led to sporadic RVF outbreaks in ruminants and humans in endemic countries, and effective vaccination of animals and humans may minimize the impact of this disease. A live-attenuated MP-12 vaccine strain is one of the best characterized RVFV strains, and was conditionally approved as a veterinary vaccine in the U.S. Live-attenuated RVF vaccines including MP-12 strain may form reassortant strains with other bunyavirus species. This study thus aimed to characterize the occurrence of genetic reassortment between the MP-12 strain and bunyavirus species closely related to RVFV. The Arumowot virus (AMTV and Gouleako goukovirus (GOLV, are transmitted by mosquitoes in Africa. The results of this study showed that GOLV does not form detectable reassortant strains with the MP-12 strain in co-infected C6/36 cells. The AMTV also did not form any reassortant strains with MP-12 strain in co-infected C6/36 cells, due to the incompatibility among N, L, and Gn/Gc proteins. A lack of reassortant formation could be due to a functional incompatibility of N and L proteins derived from heterologous species, and due to a lack of packaging via heterologous Gn/Gc proteins. The MP-12 strain did, however, randomly exchange L-, M-, and S-segments with a genetic variant strain, rMP12-GM50, in culture cells. The MP-12 strain is thus unlikely to form any reassortant strains with AMTV or GOLV in nature.

  9. Temporal association between the isolation of Sabin-related poliovirus vaccine strains and the Guillain-Barré syndrome

    OpenAIRE

    Friedrich, F.; Filippis, A. M. B.; Schatzmayr, H. G.

    1996-01-01

    Thirty eight paralysis cases classified as Guillain-Barré syndrome (GBS) in Brazil were analysed. In all these cases Sabin-related poliovirus vaccine strains were isolated. In most of the cases the last vaccine dose was given months or years before the onset of GBS, suggesting a persistent infection or the transmission of the Sabin-related strains to the patients. The isolation of Sabin-related strains from GBS cases some days or weeks after the onset of the disease, demonstrated a temporal a...

  10. Antigenic characterization of a formalin-inactivated poliovirus vaccine derived from live-attenuated Sabin strains.

    Science.gov (United States)

    Tano, Yoshio; Shimizu, Hiroyuki; Martin, Javier; Nishimura, Yorihiro; Simizu, Bunsiti; Miyamura, Tatsuo

    2007-10-10

    A candidate inactivated poliovirus vaccine derived from live-attenuated Sabin strains (sIPV), which are used in the oral poliovirus vaccine (OPV), was prepared in a large-production scale. The modification of viral antigenic epitopes during the formalin inactivation process was investigated by capture ELISA assays using type-specific and antigenic site-specific monoclonal antibodies (MoAbs). The major antigenic site 1 was modified during the formalin inactivation of Sabin 1. Antigenic sites 1-3 were slightly modified during the formalin inactivation of Sabin 2 strain. Sites 1 and 3 were altered on inactivated Sabin 3 virus. These alterations were different to those shown by wild-type Saukett strain, used in conventional IPV (cIPV). It has been previously reported that type 1 sIPV showed higher immunogenicity to type 1 cIPV whereas types 2 and 3 sIPV induced lower level of immunogenicity than their cIPV counterparts. Our results suggest that the differences in epitope structure after formalin inactivation may account, at least in part, for the observed differences in immunogenicity between Sabin and wild-type inactivated poliovaccines.

  11. Development of inactivated poliovirus vaccine from Sabin strains: A progress report.

    Science.gov (United States)

    Okayasu, Hiromasa; Sein, Carolyn; Hamidi, Ahd; Bakker, Wilfried A M; Sutter, Roland W

    2016-11-01

    The Global Polio Eradication Initiative (GPEI) has seen significant progress since it began in 1988, largely due to the worldwide use of oral poliovirus vaccine (OPV). In order to achieve polio eradication the global cessation of OPV is necessary because OPV contains live attenuated poliovirus, which in rare circumstances could re-gain wild poliovirus (WPV) characteristics with potential to establish transmission. The GPEI endgame strategy for the period 2013-2018 recommends the globally synchronised sequential cessation of the Sabin strains contained in the OPV, starting with type 2 Sabin. The withdrawal of Sabin type 2 took place in April 2016, with the introduction of at least one dose of inactivated poliovirus vaccine (IPV) as a risk mitigation strategy. The introduction of IPV into 126 countries since 2013 has required a rapid scale-up of IPV production by the two manufacturers supplying the global public sector market. This scale-up has been fraught with challenges, resulting in reductions of 40-50% of initial supply commitments. Consequently, 22 countries will not be supplied until 2018, and another 23 countries will experience serious stock-outs. In the last decade repeated calls-for-action were made to the global community to invigorate their vision and investment in developing "new poliovirus vaccines" including the development of IPV from less-virulent strains, such as Sabin-IPV (S-IPV). The conventional Salk-IPV production is limited to high-income industrialized-country manufacturers due to the containment requirements (i.e., high sanitation, low force-of-poliovirus-infection, and high population immunity). The use of Sabin strains in the production of S-IPV carries a lower biosafety risk, and was determined to be suitable for production in developing countries, expanding the manufacturing base and making IPV more affordable and accessible in the long term. Significant progress in the S-IPV has been made since 2006. S-IPV is now licensed as S-IPV in

  12. Selection of tannase-producing Aspergillus niger strains

    OpenAIRE

    Pinto,Gustavo A.S.; Leite,Selma G.F.; Terzi,Selma C.; Couri,Sonia

    2001-01-01

    The aim of this work was to select strains of Aspergillus niger for tannase production. Growth of colonies in plates with tannic acid-containing medium indicated their ability to synthesize tannase. Tannase activity was also measured in solid-state fermentation. A. niger 11T25A5 was the best tannase producer (67.5 U.g-1/72 hours of fermentation).

  13. Safety and efficacy of reduced doses of Brucella melitensis strain Rev. 1 vaccine in pregnant Iranian fat-tailed ewes

    Directory of Open Access Journals (Sweden)

    Mohammad Ebrahimi

    2012-12-01

    Full Text Available Brucellosis is one of the most important zoonotic diseases and is a significant cause of abortion in animals. Brucella melitensis strain Rev. 1 is recommended as the most effective vaccine for small ruminants but the application of full doses in adult animals is restricted. This study was conducted to determine a proper reduced dose of vaccine which confers protection but which is not abortifacient in Iranian fat-tailed sheep. A total of 51 non-vaccinated pregnant ewes were divided into three main groups and several subgroups. Ewes in different groups were vaccinated at different stages of pregnancy and various subgroups were subcutaneously immunised with different quantities of the micro-organism (7.5 × 106, 106, 5 × 105. Ewes again became pregnant a year later and were challenged with the wild-type strain to evaluate the protection conferred. Results revealed that the proportion of vaccination-induced abortions was significantly higher in ewes immunised with 7.5 × 106 Rev. 1 organisms than in those which received 106 or 5 × 105 bacteria. While 80% of non-vaccinated ewes aborted after challenge, none of the vaccinated ewes aborted post-challenge. This study indicated that a reduced dose of Rev. 1 vaccine containing 106 or 5 × 105 live cells could be safely used to induce protection in Iranian fat-tailed sheep at various stages of pregnancy.

  14. Safety and efficacy of an attenuated Chinese QX-like infectious bronchitis virus strain as a candidate vaccine.

    Science.gov (United States)

    Zhao, Ye; Cheng, Jin-long; Liu, Xiao-yu; Zhao, Jing; Hu, Yan-xin; Zhang, Guo-zhong

    2015-10-22

    Infectious bronchitis (IB) is a highly contagious respiratory and urogenital disease of chickens caused by infectious bronchitis virus (IBV). This disease is of considerable economic importance and is primarily controlled through biosecurity and immunization with live attenuated and inactivated IB vaccines of various serotypes. In the present study, we tested the safety and efficacy of an attenuated predominant Chinese QX-like IBV strain. The results revealed that the attenuated strain has a clear decrease in pathogenicity for specific-pathogen-free (SPF) chickens compared with the parent strain. Strain YN-inoculated birds had clinical signs of varying severity with 30% mortality, while the attenuated group appeared healthy, with less tissue damage. The attenuated strain also had relatively low tissue replication rates and higher antibody levels. The superior protective efficacy of the attenuated strain was observed when vaccinated birds were challenged with a homologous or heterologous field IBV strain, indicating the potential of the attenuated YN (aYN) as a vaccine. Producing a vaccine targeting the abundant serotype in China is essential to reducing the economic impact of IB on the poultry industry. Copyright © 2015 Elsevier B.V. All rights reserved.

  15. Understanding vaccination resistance: vaccine search term selection bias and the valence of retrieved information.

    Science.gov (United States)

    Ruiz, Jeanette B; Bell, Robert A

    2014-10-07

    Dubious vaccination-related information on the Internet leads some parents to opt out of vaccinating their children. To determine if negative, neutral and positive search terms retrieve vaccination information that differs in valence and confirms searchers' assumptions about vaccination. A content analysis of first-page Google search results was conducted using three negative, three neutral, and three positive search terms for the concepts "vaccine," "vaccination," and "MMR"; 84 of the 90 websites retrieved met inclusion requirements. Two coders independently and reliably coded for the presence or absence of each of 15 myths about vaccination (e.g., "vaccines cause autism"), statements that countered these myths, and recommendations for or against vaccination. Data were analyzed using descriptive statistics. Across all websites, at least one myth was perpetuated on 16.7% of websites and at least one myth was countered on 64.3% of websites. The mean number of myths perpetuated on websites retrieved with negative, neutral, and positive search terms, respectively, was 1.93, 0.53, and 0.40. The mean number of myths countered on websites retrieved with negative, neutral, and positive search terms, respectively, was 3.0, 3.27, and 2.87. Explicit recommendations regarding vaccination were offered on 22.6% of websites. A recommendation against vaccination was more often made on websites retrieved with negative search terms (37.5% of recommendations) than on websites retrieved with neutral (12.5%) or positive (0%) search terms. The concerned parent who seeks information about the risks of childhood immunizations will find more websites that perpetuate vaccine myths and recommend against vaccination than the parent who seeks information about the benefits of vaccination. This suggests that search term valence can lead to online information that supports concerned parents' misconceptions about vaccines. Copyright © 2014 Elsevier Ltd. All rights reserved.

  16. Safety and vaccine efficacy of a glycoprotein G deficient strain of infectious laryngotracheitis virus delivered in ovo.

    Science.gov (United States)

    Legione, Alistair R; Coppo, Mauricio J C; Lee, Sang-Won; Noormohammadi, Amir H; Hartley, Carol A; Browning, Glenn F; Gilkerson, James R; O'Rourke, Denise; Devlin, Joanne M

    2012-11-26

    Infectious laryngotracheitis virus (ILTV), an alphaherpesvirus, causes respiratory disease in chickens and is commonly controlled by vaccination with conventionally attenuated vaccines. Glycoprotein G (gG) is a virulence factor in ILTV and a gG deficient strain of ILTV (ΔgG-ILTV) has shown potential for use as a vaccine. In the poultry industry vaccination via drinking water is common, but technology is now available to allow quicker and more accurate in ovo vaccination of embryos at 18 days of incubation. In this study ΔgG-ILTV was delivered to chicken embryos at three different doses (10(2), 10(3) and 10(4) plaque forming units per egg) using manual in ovo vaccination. At 20 days after hatching, birds were challenged intra-tracheally with wild type ILTV and protection was measured. In ovo vaccination was shown to be safe, as there were no developmental differences between birds from hatching up to 20 days of age, as measured by weight gain. The highest dose of vaccine was the most efficacious, resulting in a weight gain not significantly different from unvaccinated/unchallenged birds seven days after challenge. In contrast, birds vaccinated with the lowest dose showed weight gains not significantly different from unvaccinated/challenged birds. Gross pathology and histopathology of the trachea reflected these observations, with birds vaccinated with the highest dose having less severe lesions. However, qPCR results suggested the vaccine did not prevent the challenge virus replicating in the trachea. This study is the first to assess in ovo delivery of a live attenuated ILTV vaccine and shows that in ovo vaccination with ΔgG-ILTV can be both safe and efficacious. Copyright © 2012 Elsevier Ltd. All rights reserved.

  17. A meningococcal NOMV-FHbp vaccine for Africa elicits broader serum bactericidal antibody responses against serogroup B and non-B strains than a licensed serogroup B vaccine.

    Science.gov (United States)

    Pajon, Rolando; Lujan, Eduardo; Granoff, Dan M

    2016-01-27

    Meningococcal epidemics in Sub-Sahara caused by serogroup A strains are controlled by a group A polysaccharide conjugate vaccine. Strains with serogroups C, W and X continue to cause epidemics. Protein antigens in licensed serogroup B vaccines are shared among serogroup B and non-B strains. Compare serum bactericidal antibody responses elicited by an investigational native outer membrane vesicle vaccine with over-expressed Factor H binding protein (NOMV-FHbp) and a licensed serogroup B vaccine (MenB-4C) against African serogroup A, B, C, W and X strains. Human Factor H (FH) transgenic mice were immunized with NOMV-FHbp prepared from a mutant African meningococcal strain containing genetically attenuated endotoxin and a mutant sub-family B FHbp antigen with low FH binding, or with MenB-4C, which contains a recombinant sub-family B FHbp antigen that binds human FH, and three other antigens, NHba, NadA and PorA P1.4, capable of eliciting bactericidal antibody. The NOMV-FHbp elicited serum bactericidal activity against 12 of 13 serogroup A, B, W or X strains from Africa, and four isogenic serogroup B mutants with sub-family B FHbp sequence variants. There was no activity against a serogroup B mutant with sub-family A FHbp, or two serogroup C isolates from a recent outbreak in Northern Nigeria, which were mismatched for both PorA and sub-family of the FHbp vaccine antigen. For MenB-4C, NHba was expressed by all 16 African isolates tested, FHbp sub-family B in 13, and NadA in five. However, MenB-4C elicited titers ≥ 1:10 against only one isolate, and against only two of four serogroup B mutant strains with sub-family B FHbp sequence variants. NOMV-FHbp has greater potential to confer serogroup-independent protection in Africa than the licensed MenB-4C vaccine. However, the NOMV-FHbp vaccine will require inclusion of sub-family A FHbp for coverage against recent serogroup C strains causing outbreaks in Northern Nigeria. Copyright © 2015 Elsevier Ltd. All rights

  18. Strain-specific Plasmodium falciparum growth inhibition among Malian children immunized with a blood-stage malaria vaccine.

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    Matthew B Laurens

    Full Text Available The blood-stage malaria vaccine FMP2.1/AS02A, comprised of recombinant Plasmodium falciparum apical membrane antigen 1 (AMA1 and the adjuvant system AS02A, had strain-specific efficacy against clinical malaria caused by P. falciparum with the vaccine strain 3D7 AMA1 sequence. To evaluate a potential correlate of protection, we measured the ability of participant sera to inhibit growth of 3D7 and FVO strains in vitro using high-throughput growth inhibition assay (GIA testing. Sera from 400 children randomized to receive either malaria vaccine or a control rabies vaccine were assessed at baseline and over two annual malaria transmission seasons after immunization. Baseline GIA against vaccine strain 3D7 and FVO strain was similar in both groups, but more children in the malaria vaccine group than in the control group had 3D7 and FVO GIA activity ≥15% 30 days after the last vaccination (day 90 (49% vs. 16%, p<0.0001; and 71.8% vs. 60.4%, p = 0.02. From baseline to day 90, 3D7 GIA in the vaccine group was 7.4 times the mean increase in the control group (p<0.0001. In AMA1 vaccinees, 3D7 GIA activity subsequently returned to baseline one year after vaccination (day 364 and did not correlate with efficacy in the extended efficacy time period to day 730. In Cox proportional hazards regression models with time-varying covariates, there was a slight suggestion of an association between 3D7 GIA activity and increased risk of clinical malaria between day 90 and day 240. We conclude that vaccination with this AMA1-based malaria vaccine increased inhibition of parasite growth, but this increase was not associated with allele-specific efficacy in the first malaria season. These results provide a framework for testing functional immune correlates of protection against clinical malaria in field trials, and will help to guide similar analyses for next-generation malaria vaccines. Clinical trials registry: This clinical trial was registered on clinicaltrials

  19. Influence of vaccine strains on the evolution of canine distemper virus.

    Science.gov (United States)

    da Fontoura Budaszewski, Renata; Streck, André Felipe; Nunes Weber, Matheus; Maboni Siqueira, Franciele; Muniz Guedes, Rafael Lucas; Wageck Canal, Cláudio

    2016-07-01

    Canine distemper virus (CDV) is a major dog pathogen belonging to the genus Morbillivirus of the family Paramyxoviridae. CDV causes disease and high mortality in dogs and wild carnivores. Although homologous recombination has been demonstrated in many members of Paramyxoviridae, these events have rarely been reported for CDV. To detect potential recombination events, the complete CDV genomes available in GenBank up to June 2015 were screened using distinct algorithms to detect genetic conversions and incongruent phylogenies. Eight putative recombinant viruses derived from different CDV genotypes and different hosts were detected. The breakpoints of the recombinant strains were primarily located on fusion and hemagglutinin glycoproteins. These results suggest that homologous recombination is a frequent phenomenon in morbillivirus populations under natural replication, and CDV vaccine strains might play an important role in shaping the evolution of this virus.

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

    Science.gov (United States)

    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. Copyright © 2012 Elsevier B.V. All rights reserved.

  1. Reversion to virulence evaluation of a 9R vaccine strain of Salmonella enterica serovar gallinarum in commercial brown layers

    Directory of Open Access Journals (Sweden)

    AS Okamoto

    2010-03-01

    Full Text Available The live vaccine Cevac S. Gallinarum, made from a rough strain of Salmonella enterica subspecies enterica serotype Gallinarum is used for preventing fowl typhoid, a disease that still causes considerable economic losses in countries with a developing poultry industry. The objective of this paper was to evaluate a possible reversion to virulence of the strain used in a vaccine in commercial brown layers. Only Salmonella-free chicks were utilized. One hundred twenty (120 12-day-old Dekalb brown layers divided in two trials were used. The first trial had six groups of 15 birds each. Birds of group 1 were vaccinated with 10 doses of Cevac S. Gallinarum subcutaneously and 10 doses orally, in a total of 20 doses of vaccine. Then the birds of groups 2, 3, 4, and 5 received inocula that contained feces and a pool of organs with fragments of liver, heart, spleen, and cecal tonsils obtained from the immediately previous group. The second trial had three groups with 10 birds each. Birds in group 7 received inocula containing a pool of organs from birds of group 5 from trial 1, whilst the birds in group 8 were vaccinated subcutaneously with one dose of vaccine. Both trials included negative control groups (6 and 9. Throughout the experimental period, birds were monitored for reactions to the vaccination on the site of administration, clinical signs, and post-mortem lesions. In each passage, in addition to the birds euthanized to provide the inocula material, two birds from each group were euthanized for assessment of possible lesions, and their organs (liver, heart, spleen and cecal tonsils were cultured in an attempt to isolate the vaccine strain. Except for one bird from group 1, that had a local reaction on the site of vaccination - a small vesicle with less that 0.5 mm that persisted until the third day post vaccination -, no other bird had any local reaction to the vaccine or any visible clinical alteration. Birds in group 8 did not present any

  2. Meningococcal B Vaccine Failure With a Penicillin-Resistant Strain in a Young Adult on Long-Term Eculizumab.

    Science.gov (United States)

    Parikh, Sydel R; Lucidarme, Jay; Bingham, Coralie; Warwicker, Paul; Goodship, Tim; Borrow, Ray; Ladhani, Shamez N

    2017-09-01

    We describe a case of invasive meningococcal disease due to a vaccine-preventable and penicillin-resistant strain in a fully immunized young adult on long-term complement inhibitor therapy and daily penicillin chemoprophylaxis. Eculizumab is a humanized monoclonal antibody that binds human complement C5 protein and inhibits the terminal complement pathway. It is currently recommended for the treatment of complement-mediated thrombotic microangiopathies. An unwanted complication of inhibiting complement, however, is an increased risk of invasive meningococcal disease. Here, we report the first case of meningococcal group B vaccine failure in a young adult receiving eculizumab for atypical hemolytic uremic syndrome. She developed invasive meningococcal disease due to a vaccine-preventable and penicillin-resistant meningococcal group B strain 4 months after receiving 2 doses of meningococcal group B vaccine while on oral penicillin prophylaxis against meningococcal infection. Copyright © 2017 by the American Academy of Pediatrics.

  3. Serologic response of SPF chickens to live vaccines and other strains of Mycoplasma gallisepticum

    Directory of Open Access Journals (Sweden)

    ER do Nascimento

    2006-03-01

    Full Text Available False positive serologic reactions and difficulties in the diagnosis of Mycoplasma gallisepticum (MG in chickens have increased lately as a result of infection by low virulent MG strains and the use of live MG vaccines in poultry. The objective of this study was to evaluate the serologic responses of SPF chickens exposed to the three commercially available live MG vaccines, and one low virulent MG strain (MG-70, contributing to the diagnosis and monitoring of MG infection in birds. Six groups of SPF chickens were used. The control group was not infected nor challenged; one group was infected with the low virulent strain MG-70 (MG-70; three groups were immunized and named after the MG vaccine used, i.e., MG-6/85, MG-ts11, and MG-F; and finally one group was infected with the virulent MG standard strain, MGR. Random Amplification of Polymorphic DNA (RAPDPCR was used to compare the strains to each other, to the standard MG-A5969, and to MGR. All strains were found to be genetically distinguishable from each other. Birds in the control group showed negative results throughout the experiment and showed no cross-reaction with M. synoviae in any serologic test. ELISA tests at 21 days post first exposure (P1E and seven days after the second exposure (P2E, evidenced that 25% of the MG70 birds were positive, whereas vaccine groups yielded higher positivity rate, i.e., 57%, 43% and 29% for MG-6/85, MG-ts11 and MG-F, respectively. Serum plate agglutination (SPA evidenced the first positive results at 35 days P1E on birds in the MG-F group at the rate of 100%; followed by 40% of birds in the MG-70 group at 63 days P1E. Chickens in MG-ts11 and MG 6/85 groups had identical behavior and yielded 100% positive SPA at 77 days P1E. In regard to hemagglutination inhibition (HI, 14 % of the birds in MG-F and MG-ts11 reacted at 42 days P1E, while MG-70 and MG-6/85 groups yielded positive results only after challenge; MG-70 birds reacted at 56 days P1E at the rate of

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

    Science.gov (United States)

    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.

  5. Evaluation of the use of various rat strains for immunogenic potency tests of Sabin-derived inactivated polio vaccines.

    Science.gov (United States)

    Someya, Yuichi; Ami, Yasushi; Takai-Todaka, Reiko; Fujimoto, Akira; Haga, Kei; Murakami, Kosuke; Fujii, Yoshiki; Shirato, Haruko; Oka, Tomoichiro; Shimoike, Takashi; Katayama, Kazuhiko; Wakita, Takaji

    2018-03-01

    Slc:Wistar rats have been the only strain used in Japan for purpose of evaluating a national reference vaccine for the Sabin-derived inactivated polio vaccine (sIPV) and the immunogenicity of sIPV-containing products. However, following the discovery that the Slc:Wistar strain was genetically related to the Fischer 344 strain, other "real" Wistar strains, such as Crlj:WI, that are available worldwide were tested in terms of their usefulness in evaluating the immunogenicity of the past and current lots of a national reference vaccine. The response of the Crlj:WI rats against the serotype 1 of sIPV was comparable to that of the Slc:Wistar rats, while the Crlj:WI rats exhibited a higher level of response against the serotypes 2 and 3. The immunogenic potency units of a national reference vaccine determined using the Slc:Wistar rats were reproduced on tests using the Crlj:WI rats. These results indicate that a titer of the neutralizing antibody obtained in response to a given dose of sIPV cannot be directly compared between these two rat strains, but that, more importantly, the potency units are almost equivalent for the two rat strains. Copyright © 2018 International Alliance for Biological Standardization. Published by Elsevier Ltd. All rights reserved.

  6. Development of stable Vibrio cholerae O1 Hikojima type vaccine strains co-expressing the Inaba and Ogawa lipopolysaccharide antigens.

    Directory of Open Access Journals (Sweden)

    Stefan L Karlsson

    Full Text Available We describe here the development of stable classical and El Tor V. cholerae O1 strains of the Hikojima serotype that co-express the Inaba and Ogawa antigens of O1 lipopolysaccharide (LPS. Mutation of the wbeT gene reduced LPS perosamine methylation and thereby gave only partial transformation into Ogawa LPS on the cell surface. The strains express approximately equal amounts of Inaba- and Ogawa-LPS antigens which are preserved after formalin-inactivation of the bacteria. Oral immunizations of both inbred and outbred mice with formalin-inactivated whole-cell vaccine preparations of these strains elicited strong intestinal IgA anti-LPS as well as serum vibriocidal antibody responses against both Inaba and Ogawa that were fully comparable to the responses induced by the licensed Dukoral vaccine. Passive protection studies in infant mice showed that immune sera raised against either of the novel Hikojima vaccine strains protected baby mice against infection with virulent strains of both serotypes. This study illustrates the power of using genetic manipulation to improve the properties of bacteria strains for use in killed whole-cell vaccines.

  7. Yellow fever virus isolated from a fatal post vaccination event: an experimental comparative study with the 17DD vaccine strain in the Syrian hamster (Mesocricetus auratus

    Directory of Open Access Journals (Sweden)

    Sueli Guerreiro Rodrigues

    2004-01-01

    Full Text Available In order to investigate the pathogenicity of the virus strain GOI 4191 that was isolated from a fatal adverse event after yellow fever virus (YFV vaccination, an experimental assay using hamsters (Mesocricetus auratus as animal model and YFV 17DD vaccine strain as virus reference was accomplished. The two virus strains were inoculated by intracerebral, intrahepatic and subcutaneous routes. The levels of viremia, antibody response, and aminotransferases were determined in sera; while virus, antigen and histopathological changes were determined in the viscera. No viremia was detected for either strain following infection; the immune response was demonstrated to be more effective to strain GOI 4191; and no significant aminotransferase levels alterations were detected. Strain GOI 4191 was recovered only from the brain of animals inoculated by the IC route. Viral antigens were detected in liver and brain by immunohistochemical assay. Histothological changes in the viscera were characterized by inflammatory infiltrate, hepatocellular necrosis, and viral encephalitis. Histological alterations and detection of viral antigen were observed in the liver of animals inoculated by the intrahepatic route. These findings were similar for both strains used in the experiment; however, significant differences were observed from those results previously reported for wild type YFV strains.

  8. [Immunogenicity of attenuated Salmonella choleraesuis vaccine strain expressing immunogenic genes of Mycoplasma hyopneumoniae in mice].

    Science.gov (United States)

    Ma, Fengying; Zou, Haoyong; He, Qigai

    2011-09-01

    The study was carried out to construct and characterize Salmonella choleraesuis vaccine strain expressing immunogenic genes of Mycoplasma hyopneumoniae and to test its immunogenicity in mice. We made p36, p46, p65 and p97R1-Nrdf, the main immunogenic genes of Mycoplasma hyopneumoniae, to insert into the prokaryotic expression plasmid pYA3493. Then these recombinant plasmids and pYA3493 were electroporated into C500 asd-mutant, resulting in the recombinant Salmonella choleraesuis vaccine strains C36 (pYA-36), C46 (pYA-46), C65 (pYA-65), C97R1-Nrdf(pYA-97R1-Nrdf) and CpYA(pYA3493). We characterized these recombinant Salmonella choleraesuis vaccine strains and tested the immunogenicity in mice by intramuscular injection or orally immunized. The results of the immunogenicity in mice indicated that the group orally immunized with C36, C46, C65, C97R1-Nrdf showed significantly higher Mycoplasma pneumoniae antibody than both the group orally immunized with C36, C46, C65 and the group intramuscular injected with the Mycoplasma hyopneumoniae bacterin (M + PAC) (P Mycoplasma hyopneumoniae bacterin (M + PAC) (P 0.05). The highest level of IL-4 was found in the group orally immunized with C36, C46, C65; higher levels of IL-4 was observed in the group orally immunized with C36, C46, C65, C97R1-Nrdf than the group injected with the Mycoplasma hyopneumoniae bacterin (M + PAC); and the lowest IL-4 level was found in the group injected with C36, C46, C65. There were no significant differences among them (P > 0.05). The Mycoplasma pneumoniae antibody, IFN-gamma or IL-4 production of the each group was obviously higher than the control group (P Mycoplasma hyopneumoniae which has immunogenicity in mice especially by intramuscular injection could probably serve as a vaccine against mycoplasmal pneumonia of swine.

  9. [History of development of the live poliomyelitis vaccine from Sabin attenuated strains in 1959 and idea of poliomyelitis eradication].

    Science.gov (United States)

    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

  10. Serological response to an indirect and a competitive elisa in heifers vaccinated with Brucella abortus strain 19

    International Nuclear Information System (INIS)

    Carrasco, E.A.; Uzal, F.A.; Echaide, S.

    1998-01-01

    The different serologic techniques for bovine brucellosis diagnosis have different abilities to detect antibodies after vaccination with Brucella abortus strain 19. The humoral response in heifers vaccinated with Brucella abortus strain 19 was evaluated by using several serologic techniques. In the experimental field of INTA, Pilcaniyeu, Rio Negro province, sixteen 5 months old heifers were vaccinated subcutaneously with a standard dose (2ml, containing 20x10 9 to 10x10 9 living organisms) of Brucella abortus strain 19. Sera from all the heifers were obtained on 18 occasions (one 87 days before vaccination, one immediately before vaccination and on 16 occasions after vaccination, during 488 days) and analyzed by buffered plate antigen test, rose bengal test, standard tube agglutination test, 2-mercaptoetanol test, complement fixation test, indirect ELISA, and competitive ELISA. Prior vaccination, 100% of the heifers gave negative results in all the techniques used, while 100% of them gave positive reaction in the first sampling after vaccination to all the techniques, with the exception of standard tube agglutination test that showed agglutinating titters of 1/100 or higher (positive threshold) in only 71.4% of the heifers. The indirect ELISA technique showed a reducing percentage of positive animals up until 316 days after vaccination, after which positive results were obtained. The competitive ELISA gave positive results in a variable number of heifers up to 253 days after vaccination when 100% of the sera were negative to this technique. Buffered plate antigen test was the technique that gave positive results for a longest period, being 100% of the animals negative to this technique at 450 days after vaccination. The other serological techniques assayed gave positive results during variable periods of time, intermediate between standard tube agglutination test and buffered plate antigen test. Although the present results were obtained from a limited number of

  11. A live oral Lawsonia intracellularis vaccine does not result in protective immunity comparable to that of a virulent strain

    DEFF Research Database (Denmark)

    Hvass, Henriette Cordes; Riber, Ulla; Ståhl, Marie

    in subclinical disease. Both groups were treated with antibiotics from day 21 to 26 and challenged at day 49 with the virulent strain. A control group (CC) only received challenge. We here report on clinical outcome, L. intracellularis infection of the intestines and immunological responses. While Re-I pigs had...... in both Vac and Re-I groups after primary inoculation/vaccination compared to the CC group. After challenge, however Vac and CC levels were high and Re-I levels low, indicating that Re-I pigs were protected from disease whereas vaccinated pigs were not. These results show that the vaccination does...

  12. Rotavirus Strain Trends During the Postlicensure Vaccine Era: United States, 2008-2013.

    Science.gov (United States)

    Bowen, Michael D; Mijatovic-Rustempasic, Slavica; Esona, Mathew D; Teel, Elizabeth N; Gautam, Rashi; Sturgeon, Michele; Azimi, Parvin H; Baker, Carol J; Bernstein, David I; Boom, Julie A; Chappell, James; Donauer, Stephanie; Edwards, Kathryn M; Englund, Janet A; Halasa, Natasha B; Harrison, Christopher J; Johnston, Samantha H; Klein, Eileen J; McNeal, Monica M; Moffatt, Mary E; Rench, Marcia A; Sahni, Leila C; Selvarangan, Rangaraj; Staat, Mary A; Szilagyi, Peter G; Weinberg, Geoffrey A; Wikswo, Mary E; Parashar, Umesh D; Payne, Daniel C

    2016-09-01

    Group A rotaviruses (RVA) are a significant cause of pediatric gastroenteritis worldwide. The New Vaccine Surveillance Network (NVSN) has conducted active surveillance for RVA at pediatric hospitals and emergency departments at 3-7 geographically diverse sites in the United States since 2006. Over 6 consecutive years, from 2008 to 2013, 1523 samples from NVSN sites that were tested positive by a Rotaclone enzyme immunoassay were submitted to the Centers for Disease Control and Prevention for genotyping. In the 2009, 2010, and 2011 seasons, genotype G3P[8] was the predominant genotype throughout the network, with a 46%-84% prevalence. In the 2012 season, G12P[8] replaced G3P[8] as the most common genotype, with a 70% prevalence, and this trend persisted in 2013 (68.0% prevalence). Vaccine (RotaTeq; Rotarix) strains were detected in 0.6%-3.4% of genotyped samples each season. Uncommon and unusual strains (eg, G8P[4], G3P[24], G2P[8], G3P[4], G3P[6], G24P[14], G4P[6], and G9P[4]) were detected sporadically over the study period. Year, study site, and race were found to be significant predictors of genotype. Continued active surveillance is needed to monitor RVA genotypes in the United States and to detect potential changes since vaccine licensure. Published by Oxford University Press for the Infectious Diseases Society of America 2016. This work is written by (a) US Government employee(s) and is in the public domain in the US.

  13. Factors influencing preclinical in vivo evaluation of mumps vaccine strain immunogenicity.

    Science.gov (United States)

    Halassy, B; Kurtović, T; Brgles, M; Lang Balija, M; Forčić, D

    2015-01-01

    Immunogenicity testing in animals is a necessary preclinical assay for demonstration of vaccine efficacy the results of which are often the basis for the decision whether to proceed or withdraw the further development of the novel vaccine candidate. However, in vivo assays are rarely, if at all, optimized and validated. Here we clearly demonstrate the importance of in vivo assay (mumps virus immunogenicity testing in guinea pigs) optimization for gaining reliable results and the suitability of Fractional factorial design of experiments (DoE) for such a purpose. By the use of DoE with resolution IV (2IV((4-1))) we clearly revealed that the parameters significantly increasing assay sensitivity were interval between animal immunizations followed by the body weight of experimental animals. The quantity (0 versus 2%) of the stabilizer (fetal bovine serum, FBS) in the sample was shown as non-influencing parameter in DoE setup. However, the separate experiment investigating only the FBS influence, and performed under other parameters optimally set, showed that FBS also influences the results of immunogenicity assay. Such finding indicated that (a) factors with strong influence on the measured outcome can hide the effects of parameters with modest/low influence and (b) the matrix of mumps virus samples to be compared for immunogenicity must be identical for reliable virus immunogenicity comparison. Finally the 3 mumps vaccine strains widely used for decades in the licensed vaccines were for the first time compared in an animal model, and results obtained were in line with their reported immunogenicity in human population supporting the predictive power of the optimized in vivo assay.

  14. Vaccination Against Toxoplasmosis (RH Virulent Strain) by Using Gamma Irradiated Cysts to Protect Sheep from Infection

    International Nuclear Information System (INIS)

    Moawad, M.A.; El Gawish, M.A.

    2005-01-01

    Joxoplasma gondii is perhaps the most prevalent parasitic infection of human in the world, although only a limited number of individuals actually become symptomatic from infection. It would be desirable to have a vaccine for the immunization of sheep to prevent abortion because sheep can develop a protective immunity against infection with T. gondii. The present study was designed to produce a vaccine against T. gondii in sheep using an optimum dose of gamma irradiation (0.4 kGy). Twenty seven of female sheep serologi-cally free from T. gondii were divided into three groups, nine for each group. Two groups were injected with the proposed vaccine at dose of 2 ml and 3 ml to stimulate the immune response. The third group was left without immunization and served as control group. The liters of T. gondii antibodies were assayed for eight weeks after immunization by modified agglutination test. After a month of pregnancy, the three groups were challenged with a virulent RH strain of 7| gondii. The results of these study revealed that the immunized groups of sheep with 2 or 3 ml of gamma irradiated cysts of T. gondii gave healthy lambs with normal weight, while the control group suffered from abortion. This work with further investigation is promising for commercial production of vaccine to protect animals from T. gondii infection and consequently prevent the transmission of the disease to human. n addition to humans, T. gondii can infect all mammalian species. It is a major :ause of abortion in domestic livestock making it a major economic concern to igriculture industry. As a result of the hidden nature of toxoplasmosis, many aimers remain unaware of the true cause of the losses they are suffering. Abortions, stillbirths and neonatal mortality occur when susceptible sheep ire infected during pregnancy (Buxton, 1991). Infection of sheep in early ;estation leads to death and re-absorption of the fetus and can be mistaken for nfertility (Johnston, 1988)

  15. Characterization of two recent Japanese field isolates of canine distemper virus and examination of the avirulent strain utility as an attenuated vaccine.

    Science.gov (United States)

    Takenaka, Akiko; Yoneda, Misako; Seki, Takahiro; Uema, Masashi; Kooriyama, Takanori; Nishi, Toshiya; Fujita, Kentaro; Miura, Ryuichi; Tsukiyama-Kohara, Kyoko; Sato, Hiroki; Kai, Chieko

    2014-12-05

    Recently, several new strains of canine distemper virus (CDV) have been isolated in Japan. To investigate their pathogenesis in dogs, the Yanaka and Bunkyo-K strains were investigated by infecting dogs and determining clinical signs, amount of virus, and antibody responses. The Yanaka strain is avirulent and induced an antibody response. The Bunkyo-K strain induced typical CDV clinical signs in infected dogs and virulence was enhanced by brain passage. Molecular and phylogenetic analyses of H genes demonstrated the Bunkyo-K strains were of a different lineage from Asia-1 group including the Yanaka strain and Asia-2 group that contain recent Japanese isolates, which were recently identified as major prevalent strains worldwide but distinct from old vaccine strains. Based on these data, we tested the ability of the Yanaka strain for vaccination. Inoculation with the Yanaka strain efficiently induced CDV neutralizing antibodies with no clinical signs, and the protection effects against challenge with either old virulent strain or Bunkyo-K strain were equal or greater when compared with vaccination by an original vaccine strain. Thus, the Yanaka strain is a potential vaccine candidate against recent prevalent CDV strains. Copyright © 2014 Elsevier B.V. All rights reserved.

  16. Different levels of immunogenicity of two strains of Fowlpox virus as recombinant vaccine vectors eliciting T-cell responses in heterologous prime-boost vaccination strategies.

    Science.gov (United States)

    Cottingham, Matthew G; van Maurik, Andre; Zago, Manola; Newton, Angela T; Anderson, Richard J; Howard, M Keith; Schneider, Jörg; Skinner, Michael A

    2006-07-01

    The FP9 strain of F has been described as a more immunogenic recombinant vaccine vector than the Webster FPV-M (FPW) strain (R. J. Anderson et al., J. Immunol. 172:3094-3100, 2004). This study expands the comparison to include two separate recombinant antigens and multiple, rather than single, independent viral clones derived from the two strains. Dual-poxvirus heterologous prime-boost vaccination regimens using individual clones of recombinant FP9 or FPW in combination with recombinant modified V Ankara expressing the same antigen were evaluated for their ability to elicit T-cell responses against recombinant antigens from Plasmodium berghei (circumsporozoite protein) or human immunodeficiency virus type 1 (a Gag-Pol-Nef fusion protein). Gamma interferon enzyme-linked immunospot assay and fluorescence-activated cell sorting assays of the responses to specific epitopes confirmed the approximately twofold-greater cellular immunogenicity of FP9 compared to FPW, when given as the priming or boosting immunization. Equality of transgene expression in mouse cells infected with the two strains in vitro was verified by Western blotting. Directed partial sequence analysis and PCR analysis of FPW and comparison to available whole-genome sequences revealed that many loci that are mutated in the highly attenuated and culture-adapted FP9 strain are wild type in FPW, including the seven multikilobase deletions. These "passage-specific" alterations are hypothesized to be involved in determining the immunogenicity of fowlpox virus as a recombinant vaccine vector.

  17. Antibody responses of Macaca fascicularis against a new inactivated polio vaccine derived from Sabin strains (sIPV) in DTaP-sIPV vaccine.

    Science.gov (United States)

    Sato, Y; Shiosaki, K; Goto, Y; Sonoda, K; Kino, Y

    2013-05-01

    Antibody responses of Macaca fascicularis against a new tetravalent vaccine composed of diphtheria toxoid, tetanus toxoid, acellular pertussis antigens, and inactivated poliovirus derived from Sabin strains (sIPV) was investigated to predict an optimal dose of sIPV in a new tetravalent vaccine (DTaP-sIPV) prior to conducting a dose-defined clinical study. Monkeys were inoculated with DTaP-sIPVs containing three different antigen units of sIPVs: Vaccine A (types 1:2:3 = 3:100:100 DU), Vaccine B (types 1:2:3 = 1.5:50:50 DU), and Vaccine C (types 1:2:3 = 0.75:25:25 DU). There was no difference in the average titers of neutralizing antibody against the attenuated or virulent polioviruses between Vaccines A and B. The average neutralizing antibody titers of Vaccine C tended to be lower than those of Vaccines A and B. The sIPV antigens did not affect the anti-diphtheria or anti-tetanus antibody titers of DTaP-sIPV. Furthermore, the average neutralizing antibody titers of Vaccine A against the attenuated and virulent polioviruses were comparable between M. fascicularis and humans. These results suggest that M. fascicularis may be a useful animal model for predicting the antibody responses to sIPVs in humans, and that it may be likely to reduce the amount of sIPVs contained in DTaP-sIPVs, even for humans. Copyright © 2013 The International Alliance for Biological Standardization. Published by Elsevier Ltd. All rights reserved.

  18. Attenuation of the goose parvovirus strain B. Laboratory and field trials of the attenuated mutant for vaccination against Derzsy's disease.

    Science.gov (United States)

    Kisary, J; Derzsy, D; Meszaros, J

    1978-07-01

    Serial transfer of the goose parvovirus strain B, causal agent of Derzsy's gosling disease, in cultured goose-embryo fibroblast (GEF) resulted in a mutant (designated as Bav) apathogenic for both goose embryos and susceptible goslings. Goose embryos inoculated with the 38th or higher passages of strain B survived the infection, although the virus replicated in their organs. Susceptible goslings survived challenge with the Bav strain without showing symptoms, and developed normally. Only 4.2% of gosling progeny of parents vaccinated twice with strain Bav died after challenge with the virulent strain B goose parvovirus compared with 95% of gosling progeny of unvaccinated parents. Progeny of vaccinated and unvaccinated geese were placed on a farm on which Derzsy's disease was present. During the first month of life mortality was 7.7% in the progeny of vaccinated geese compared with 59.8% in the progeny of the unvaccinated geese. At 8 weeks of age the mean weight of the vaccinated goslings was 20% greater than for the unvaccinated goslings. These results indicate that the attenuated apathogenic Bav mutant is suitable for the immunisation of layers to protect their progeny by passive immunisation against Derzsy's disease.

  19. Differentiation of canine distemper virus isolates in fur animals from various vaccine strains by reverse transcription-polymerase chain reaction-restriction fragment length polymorphism according to phylogenetic relations in china

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    Zhao Jianjun

    2011-02-01

    Full Text Available Abstract In order to effectively identify the vaccine and field strains of Canine distemper virus (CDV, a new differential diagnostic test has been developed based on reverse transcription-polymerase chain reaction (RT-PCR and restriction fragment length polymorphism (RFLP. We selected an 829 bp fragment of the nucleoprotein (N gene of CDV. By RFLP analysis using BamHI, field isolates were distinguishable from the vaccine strains. Two fragments were obtained from the vaccine strains by RT-PCR-RFLP analysis while three were observed in the field strains. An 829 nucleotide region of the CDV N gene was analyzed in 19 CDV field strains isolated from minks, raccoon dogs and foxes in China between 2005 and 2007. The results suggest this method is precise, accurate and efficient. It was also determined that three different genotypes exist in CDV field strains in fur animal herds of the north of China, most of which belong to Asian type. Mutated field strains, JSY06-R1, JSY06-R2 and JDH07-F1 also exist in Northern China, but are most closely related to the standard virulent strain A75/17, designated in Arctic and America-2 genetype in the present study, respectively.

  20. Determination of Volatile Organic Compounds in Selected Strains of Cyanobacteria

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    Ivan Milovanović

    2015-01-01

    Full Text Available Microalgal biomass can be used in creating various functional food and feed products, but certain species of microalgae and cyanobacteria are known to produce various compounds causing off-flavour. In this work, we investigated selected cyanobacterial strains of Spirulina, Anabaena, and Nostoc genera originating from Serbia, with the aim of determining the chemical profile of volatile organic compounds produced by these organisms. Additionally, the influence of nitrogen level during growth on the production of volatile compounds was investigated for Nostoc and Anabaena strains. In addition, multivariate techniques, namely, principal component analysis (PCA and hierarchical cluster analysis (HCA, were used for making distinction among different microalgal strains. The results show that the main volatile compounds in these species are medium chain length alkanes, but other odorous compounds such as 2-methylisoborneol (0.51–4.48%, 2-pentylfuran (0.72–8.98%, β-cyclocitral (0.00–1.17%, and β-ionone (1.15–2.72% were also detected in the samples. Addition of nitrogen to growth medium was shown to negatively affect the production of 2-methylisoborneol, while geosmin was not detected in any of the analyzed samples, which indicates that the manipulation of growth conditions may be useful in reducing levels of some unwanted odor-causing components.

  1. Private selective sweeps identified from next-generation pool-sequencing reveal convergent pathways under selection in two inbred Schistosoma mansoni strains.

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    Julie A J Clément

    Full Text Available BACKGROUND: The trematode flatworms of the genus Schistosoma, the causative agents of schistosomiasis, are among the most prevalent parasites in humans, affecting more than 200 million people worldwide. In this study, we focused on two well-characterized strains of S. mansoni, to explore signatures of selection. Both strains are highly inbred and exhibit differences in life history traits, in particular in their compatibility with the intermediate host Biomphalaria glabrata. METHODOLOGY/PRINCIPAL FINDINGS: We performed high throughput sequencing of DNA from pools of individuals of each strain using Illumina technology and identified single nucleotide polymorphisms (SNP and copy number variations (CNV. In total, 708,898 SNPs were identified and roughly 2,000 CNVs. The SNPs revealed low nucleotide diversity (π = 2 × 10(-4 within each strain and a high differentiation level (Fst = 0.73 between them. Based on a recently developed in-silico approach, we further detected 12 and 19 private (i.e. specific non-overlapping selective sweeps among the 121 and 151 sweeps found in total for each strain. CONCLUSIONS/SIGNIFICANCE: Functional annotation of transcripts lying in the private selective sweeps revealed specific selection for functions related to parasitic interaction (e.g. cell-cell adhesion or redox reactions. Despite high differentiation between strains, we identified evolutionary convergence of genes related to proteolysis, known as a key virulence factor and a potential target of drug and vaccine development. Our data show that pool-sequencing can be used for the detection of selective sweeps in parasite populations and enables one to identify biological functions under selection.

  2. Proteomic profile of culture filtrate from the Brazilian vaccine strain Mycobacterium bovis BCG Moreau compared to M. bovis BCG Pasteur

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    Degrave Wim M

    2011-04-01

    Full Text Available Abstract Background Bacille Calmette-Guerin (BCG is currently the only available vaccine against tuberculosis (TB and comprises a heterogeneous family of sub-strains with genotypic and phenotypic differences. The World Health Organization (WHO affirms that the characterization of BCG sub-strains, both on genomic and proteomic levels, is crucial for a better comprehension of the vaccine. In addition, these studies can contribute in the development of a more efficient vaccine against TB. Here, we combine two-dimensional electrophoresis (2DE and mass spectrometry to analyse the proteomic profile of culture filtrate proteins (CFPs from M. bovis BCG Moreau, the Brazilian vaccine strain, comparing it to that of BCG Pasteur. CFPs are considered of great importance given their dominant immunogenicity and role in pathogenesis, being available for interaction with host cells since early infection. Results The 2DE proteomic map of M. bovis BCG Moreau CFPs in the pH range 3 - 8 allowed the identification of 158 spots corresponding to 101 different proteins, identified by MS/MS. Comparison to BCG Pasteur highlights the great similarity between these BCG strains. However, quantitative analysis shows a higher expression of immunogenic proteins such as Rv1860 (BCG1896, Apa, Rv1926c (BCG1965c, Mpb63 and Rv1886c (BCG1923c, Ag85B in BCG Moreau when compared to BCG Pasteur, while some heat shock proteins, such as Rv0440 (BCG0479, GroEL2 and Rv0350 (BCG0389, DnaK, show the opposite pattern. Conclusions Here we report the detailed 2DE profile of CFPs from M. bovis BCG Moreau and its comparison to BCG Pasteur, identifying differences that may provide relevant information on vaccine efficacy. These findings contribute to the detailed characterization of the Brazilian vaccine strain against TB, revealing aspects that may lead to a better understanding of the factors leading to BCG's variable protective efficacy against TB.

  3. Identification of sequence changes in live attenuated goose parvovirus vaccine strains developed in Asia and Europe.

    Science.gov (United States)

    Shien, J-H; Wang, Y-S; Chen, C-H; Shieh, H K; Hu, C-C; Chang, P-C

    2008-10-01

    Live attenuated vaccines have been used for control of the disease caused by goose parvovirus (GPV), but the mechanism involved in attenuation of GPV remains elusive. This report presents the complete nucleotide sequences of two live attenuated strains of GPV (82-0321V and VG32/1) that were independently developed in Taiwan and Europe, together with the parental strain of 82-0321V and a field strain isolated in Taiwan in 2006. Sequence comparisons showed that 82-0321V and VG32/1 had multiple deletions and substitutions in the inverted terminal repeats region when compared with their parental strain or the field virus, but these changes did not affect the formation of the hairpin structure essential for viral replication. Moreover, 82-0321V and VG32/1 had five amino acid changes in the non-structural protein, but these changes were located at positions distant from known functional motifs in the non-structural protein. In contrast, 82-0321V had nine changes and VG32/1 had 11 changes in their capsid proteins (VP1), and the majority of these changes occurred at positions close to the putative receptor binding sites of VP1, as predicted using the structure of adeno-associated virus 2 as the model system. Taken together, the results suggest that changes in sequence near the receptor binding sites of VP1 might be responsible for attenuation of GPV. This is the first report of complete nucleotide sequences of GPV other than the virulent B strain, and suggests a possible mechanism for attenuation of GPV.

  4. Cold-Adapted Viral Attenuation (CAVA): Highly Temperature Sensitive Polioviruses as Novel Vaccine Strains for a Next Generation Inactivated Poliovirus Vaccine.

    Science.gov (United States)

    Sanders, Barbara P; de Los Rios Oakes, Isabel; van Hoek, Vladimir; Bockstal, Viki; Kamphuis, Tobias; Uil, Taco G; Song, Yutong; Cooper, Gillian; Crawt, Laura E; Martín, Javier; Zahn, Roland; Lewis, John; Wimmer, Eckard; Custers, Jerome H H V; Schuitemaker, Hanneke; Cello, Jeronimo; Edo-Matas, Diana

    2016-03-01

    The poliovirus vaccine field is moving towards novel vaccination strategies. Withdrawal of the Oral Poliovirus Vaccine and implementation of the conventional Inactivated Poliovirus Vaccine (cIPV) is imminent. Moreover, replacement of the virulent poliovirus strains currently used for cIPV with attenuated strains is preferred. We generated Cold-Adapted Viral Attenuation (CAVA) poliovirus strains by serial passage at low temperature and subsequent genetic engineering, which contain the capsid sequences of cIPV strains combined with a set of mutations identified during cold-adaptation. These viruses displayed a highly temperature sensitive phenotype with no signs of productive infection at 37°C as visualized by electron microscopy. Furthermore, decreases in infectious titers, viral RNA, and protein levels were measured during infection at 37°C, suggesting a block in the viral replication cycle at RNA replication, protein translation, or earlier. However, at 30°C, they could be propagated to high titers (9.4-9.9 Log10TCID50/ml) on the PER.C6 cell culture platform. We identified 14 mutations in the IRES and non-structural regions, which in combination induced the temperature sensitive phenotype, also when transferred to the genomes of other wild-type and attenuated polioviruses. The temperature sensitivity translated to complete absence of neurovirulence in CD155 transgenic mice. Attenuation was also confirmed after extended in vitro passage at small scale using conditions (MOI, cell density, temperature) anticipated for vaccine production. The inability of CAVA strains to replicate at 37°C makes reversion to a neurovirulent phenotype in vivo highly unlikely, therefore, these strains can be considered safe for the manufacture of IPV. The CAVA strains were immunogenic in the Wistar rat potency model for cIPV, inducing high neutralizing antibody titers in a dose-dependent manner in response to D-antigen doses used for cIPV. In combination with the highly productive

  5. Diagnostic tools based on minor groove binder probe technology for rapid identification of vaccinal and field strains of canine parvovirus type 2b.

    Science.gov (United States)

    Decaro, Nicola; Martella, Vito; Elia, Gabriella; Desario, Costantina; Campolo, Marco; Buonavoglia, Domenico; Bellacicco, Anna Lucia; Tempesta, Maria; Buonavoglia, Canio

    2006-12-01

    TaqMan-based diagnostic tests have been developed for the identification of canine parvovirus type 2 (CPV-2) strains in the faeces of dogs with diarrhoea, including a minor groove binder (MGB) probe assay for identification of type 2-based vaccines and field strains (types 2a, 2b and 2c). Since type 2b vaccines have been licensed recently in Europe, two novel MGB assays were developed for discrimination between type 2b vaccines and field strains of CPV. Such assays have been found to be highly sensitive, specific and reproducible, allowing for simultaneous detection of type 2b vaccinal and field strains present in the same specimens. These new assays will help resolution of the diagnostic problems related to the detection of a type 2b strain in the faeces of dogs shortly after the administration of a type 2b vaccine.

  6. Selective hepatitis B virus vaccination has reduced hepatitis B virus transmission in the Netherlands.

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    Susan Hahné

    Full Text Available BACKGROUND & AIMS: In the Netherlands, a selective hepatitis B virus (HBV vaccination programme started in 2002 for men having sex with men, drug users, commercial sex workers and heterosexuals with frequent partner changes. We assessed the programme's effectiveness to guide policy on HBV prevention. METHODS: We analysed reports of acute HBV infection in the Netherlands between 2004 and 2010 requesting serum from patients for HBV-genome S- and C-region sequencing. We used coalescence analyses to assess genetic diversity of nonimported genotype-A cases over time. RESULTS: 1687 patients with acute HBV infection were reported between 2004 and 2010. The incidence of reported acute HBV infection decreased from 1.8 to 1.2 per 100,000 inhabitants, mostly due to a reduction in the number of cases in men who have sex with men. Men were overrepresented among cases with an unknown route of transmission, especially among genotype A2 cases mainly associated with transmission through male homosexual contact. The genetic diversity of nonimported genotype-A strains obtained from men who have sex with men decreased from 2006 onwards, suggesting HBV incidence in this group decreased. CONCLUSIONS: The selective HBV-vaccination programme for behavioural high-risk groups very likely reduced the incidence of HBV infection in the Netherlands mainly by preventing HBV infections in men who have sex with men. A considerable proportion of cases in men who did not report risk behaviour was probably acquired through homosexual contact. Our findings support continuation of the programme, and adopting similar approaches in other countries where HBV transmission is focused in high-risk adults.

  7. Selective Hepatitis B Virus Vaccination Has Reduced Hepatitis B Virus Transmission in The Netherlands

    Science.gov (United States)

    Koedijk, Femke; van Ballegooijen, Marijn; Cremer, Jeroen; Bruisten, Sylvia; Coutinho, Roel

    2013-01-01

    Background & Aims In the Netherlands, a selective hepatitis B virus (HBV) vaccination programme started in 2002 for men having sex with men, drug users, commercial sex workers and heterosexuals with frequent partner changes. We assessed the programme's effectiveness to guide policy on HBV prevention. Methods We analysed reports of acute HBV infection in the Netherlands between 2004 and 2010 requesting serum from patients for HBV-genome S- and C-region sequencing. We used coalescence analyses to assess genetic diversity of nonimported genotype-A cases over time. Results 1687 patients with acute HBV infection were reported between 2004 and 2010. The incidence of reported acute HBV infection decreased from 1.8 to 1.2 per 100,000 inhabitants, mostly due to a reduction in the number of cases in men who have sex with men. Men were overrepresented among cases with an unknown route of transmission, especially among genotype A2 cases mainly associated with transmission through male homosexual contact. The genetic diversity of nonimported genotype-A strains obtained from men who have sex with men decreased from 2006 onwards, suggesting HBV incidence in this group decreased. Conclusions The selective HBV-vaccination programme for behavioural high-risk groups very likely reduced the incidence of HBV infection in the Netherlands mainly by preventing HBV infections in men who have sex with men. A considerable proportion of cases in men who did not report risk behaviour was probably acquired through homosexual contact. Our findings support continuation of the programme, and adopting similar approaches in other countries where HBV transmission is focused in high-risk adults. PMID:23922651

  8. Molecular characterization of rotavirus strains detected during a clinical trial of a human rotavirus vaccine in Blantyre, Malawi

    Science.gov (United States)

    Nakagomi, Toyoko; Nakagomi, Osamu; Dove, Winifred; Doan, Yen Hai; Witte, Desiree; Ngwira, Bagrey; Todd, Stacy; Steele, A Duncan; Neuzil, Kathleen M; Cunliffe, Nigel A

    2014-01-01

    The human, G1P[8] rotavirus vaccine (Rotarix) significantly reduced severe rotavirus gastroenteritis episodes in a clinical trial in South Africa and Malawi, but vaccine efficacy was lower in Malawi (49.5%) than reported in South Africa (76.9%) and elsewhere. The aim of this study was to examine the molecular relationships of circulating wild-type rotaviruses detected during the clinical trial in Malawi to RIX4414 (the strain contained in Rotarix) and to common human rotavirus strains. Of 88 rotavirus-positive, diarrhoeal stool specimens, 43 rotaviruses exhibited identifiable RNA migration patterns when examined by polyacrylamide gel electrophoresis. The genes encoding VP7, VP4, VP6 and NSP4 of 5 representative strains possessing genotypes G12P[6], G1P[8], G9P[8], and G8P[4] were sequenced. While their VP7 (G) and VP4 (P) genotype designations were confirmed, the VP6 (I) and NSP4 (E) genotypes were either I1E1 or I2E2, indicating that they were of human rotavirus origin. RNA-RNA hybridization using 21 culture-adapted strains showed that Malawian rotaviruses had a genomic RNA constellation common to either the Wa-like or DS-1 like human rotaviruses. Overall, the Malawi strains appear similar in their genetic make-up to rotaviruses described in countries where vaccine efficacy is greater, suggesting that the lower efficacy in Malawi is unlikely to be explained by the diversity of circulating strains. PMID:22520123

  9. Characterization of near full-length genomes of HIV type 1 strains in Denmark: Basis for a universal therapeutic vaccine

    DEFF Research Database (Denmark)

    Andresen, Betina S.; Vinner, Lasse; Tang, Sheila Tuyet

    2007-01-01

    We report here the near full-length sequence characterization of 17 Danish clinical HIV-1 strains isolated from HLA-A02 patients not in need of ART, with relatively low viral loads and normal CD4 cell counts. Sequencing was performed directly on DNA extracted from short-term cocultures of PBMCs...... of a universal immunotherapeutic vaccine construct based on these epitopes....

  10. A novel rapid direct haemagglutination-inhibition assay for measurements of humoral immune response against non-haemagglutinating Fowlpox virus strains in vaccinated chickens.

    Science.gov (United States)

    Wambura, Philemon N; Mzula, Alexanda

    2017-10-01

    Fowlpox (FP) is a serious disease in chickens caused by Fowlpox virus (FPV). One method currently used to control FPV is vaccination followed by confirmation that antibody titres are protective using the indirect haemagglutination assay (IHA). The direct haemagglutination inhibition (HI) assay is not done because most FPV strains do not agglutinate chicken red blood cells (RBCs). A novel FPV strain TPV-1 which agglutinates chicken RBCs was discovered recently and enabled a direct HI assay to be conducted using homologous sera. This study is therefore aimed at assessing the direct HI assay using a recently discovered novel haemagglutinating FPV strain TPV-1 in chickens vaccinated with a commercial vaccine containing a non-haemagglutinating FPV.Chicks vaccinated with FPV at 1 day-old had antibody geometric mean titres (GMT) of log 2 3.7 at 7 days after vaccination and log 2 8.0 at 28 days after vaccination when tested in the direct HI. Chickens vaccinated at 6 weeks-old had antibody geometric mean titres (GMT) of log 2 5.0 at 7 days after vaccination and log 2 8.4 at 28 days after vaccination when tested in the direct HI. The GMT recorded 28 days after vaccination was slightly higher in chickens vaccinated at 6-week-old than in chicks vaccinated at one-day-old. However, this difference was not significant (P > 0.05). All vaccinated chickens showed "takes". No antibody response to FPV and "takes" were detected in unvaccinated chickens (GMT 0.05). These findings indicate that a simple and rapid direct HI assay using the FPV TPV-1 strain as antigen may be used to measure antibody levels in chickens vaccinated with non-haemagglutinating strains of FPV, and that the titres are comparable to those obtained by indirect IHA.

  11. Study on the efficacy and safety of different antigens and oil formulations of infectious coryza vaccines containing an NAD-independent strain of Avibacterium paragallinarum

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    B. Dungu

    2009-09-01

    Full Text Available The present study was designed to assess and compare three different formulations of the new Onderstepoort infectious coryza (IC quadrivalent vaccine, which contain an NAD-independent strain of Avibacterium paragallinarum (previously known as Haemophilus paragallinarum, and a commercial IC vaccine, not containing an NAD-independent strain, for their safety and ability to protect chickens of varying ages against virulent challenges with four different serovars of A. paragallinarum, including the NAD-independent strain of the C-3 serovar. Four groups of 140 chickens each were vaccinated at the age of 17 weeks and revaccinated at the age of 19 weeks with each of the four vaccine formulations. A similar sized group of non-vaccinated chickens was used as control. Two rounds of challenge were conducted: a group of chicken in each vaccination group was challenged between 31 and 35 weeks of age, while another group was challenged between 51 and 55 weeks of age. The ''in-contact'' challenge model was used in this experiment. For each vaccination group, the four challenge strains representing four local serovars were used in each challenge round. The efficacy of the vaccines was compared based on overall protection levels obtained and the duration of protection. The safety of the different vaccines was determined by the severity of post-vaccination reactions. The need for the incorporation of the NAD-independent strain in the vaccine was evidenced by the low protection level against NAD-independent challenge recorded in the group of birds vaccinated with the commercial vaccine. The results obtained confirmed not only the variation in virulence of different South African serovars, with serovar C-3 being the most virulent and serovar B having almost no virulence but also the age related increase in susceptibility. The importance of a suitable formulation of the vaccine is discussed.

  12. Phase 3 Trial of a Sabin Strain-Based Inactivated Poliovirus Vaccine.

    Science.gov (United States)

    Liao, Guoyang; Li, Rongcheng; Li, Changgui; Sun, Mingbo; Jiang, Shude; Li, Yanping; Mo, Zhaojun; Xia, Jielai; Xie, Zhongping; Che, Yanchun; Yang, Jingsi; Yin, Zhifang; Wang, Jianfeng; Chu, Jiayou; Cai, Wei; Zhou, Jian; Wang, Junzhi; Li, Qihan

    2016-12-01

     The development of a Sabin strain-based inactivated poliovirus vaccine (Sabin-IPV) is imperative to protecting against vaccine-associated paralytic poliomyelitis in developing countries.  In this double-blinded, parallel-group, noninferiority trial, eligible infants aged 60-90 days were randomly assigned in a ratio of 1:1 to receive either 3 doses of Sabin-IPV or Salk strain-based IPV (Salk-IPV) at 30-day intervals and a booster at the age of 18 months. Immunogenicity and safety were assessed on the basis of a protocol.  Of 1438 infants, 1200 eligible infants were recruited and received either Sabin-IPV or Salk-IPV. From the Sabin-IPV and Salk-IPV groups, 570 and 564 infants, respectively, completed the primary immunization and formed the per-protocol population. The seroconversion rates of the participants who received Sabin-IPV were 100%, 94.9%, and 99.0% (types I, II, and III, respectively), and those of the participants who received Salk-IPV were 94.7%, 91.3%, and 97.9% 1 month after the completion of primary immunization. An anamnestic response for poliovirus types I, II, and III was elicited by a booster in both groups. Except in the case of fever, other adverse events were similar between the 2 groups.  The immune response induced by Sabin-IPV was not inferior to that established with Salk-IPV. © The Author 2016. Published by Oxford University Press for the Infectious Diseases Society of America. All rights reserved. For permissions, e-mail journals.permissions@oup.com.

  13. The early use of yellow fever virus strain 17D for vaccine production in Brazil - a review

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    Paulo Roberto Post

    2001-08-01

    Full Text Available The use of yellow fever (YF virus 17D strain for vaccine production adapted in Brazil since its introduction in 1937 was reviewed. This was possible due to the availability of official records of vaccine production. The retrieved data highlight the simultaneous use of several serially passaged 17D substrain viruses for both inocula and vaccine preparation that allowed uninterrupted production. Substitution of these substrain viruses became possible with the experience gained during quality control and human vaccination. Post-vaccinal complications in humans and the failure of some viruses in quality control tests (neurovirulence for monkeys indicated that variables needed to be reduced during vaccine production, leading to the development of the seed lot system. The 17DD substrain, still used today, was the most frequently used substrain and the most reliable in terms of safety and efficacy. For this reason, it is possible to derive an infectious cDNA clone of this substrain combined with production in cell culture that could be used to direct the expression of heterologous antigens and lead to the development of new live vaccines.

  14. Antibodies induced by vaccination with purified chick embryo cell culture vaccine (PCECV) cross-neutralize non-classical bat lyssavirus strains.

    Science.gov (United States)

    Malerczyk, Claudius; Selhorst, Thomas; Tordo, Noël; Moore, Susan; Müller, Thomas

    2009-08-27

    Tissue-culture vaccines like purified chick embryo cell vaccine (PCECV) have been shown to provide protection against classical rabies virus (RABV) via pre-exposure or post-exposure prophylaxis. A cross-neutralization study was conducted using a panel of 100 human sera, to determine, to what extent after vaccination with PCECV protection exists against non-classical bat lyssavirus strains like European bat lyssavirus (EBLV) type 1 and 2 and Australian bat lyssavirus (ABLV). Virus neutralizing antibody (VNA) concentrations against the rabies virus variants CVS-11, ABLV, EBLV-1 and EBLV-2 were determined by using a modified rapid fluorescent focus inhibition test. For ABLV and EBLV-2, the comparison to CVS-11 revealed almost identical results (100% adequate VNA concentrations >or=0.5 IU/mL; correlation coefficient r(2)=0.69 and 0.77, respectively), while for EBLV-1 more scattering was observed (97% adequate VNA concentrations; r(2)=0.50). In conclusion, vaccination with PCECV produces adequate VNA concentrations against classical RABV as well as non-classical lyssavirus strains ABLV, EBLV-1, and EBLV-2.

  15. Acute hepatitis B caused by a vaccine-escape HBV strain in vaccinated subject: sequence analysis and therapeutic strategy.

    Science.gov (United States)

    Luongo, Monica; Critelli, Rosina; Grottola, Antonella; Gitto, Stefano; Bernabucci, Veronica; Bevini, Mirco; Vecchi, Chiara; Montagnani, Giuliano; Villa, Erica

    2015-01-01

    HBV vaccine contains the 'a' determinant region, the major immune-target of antibodies (anti-HBs). Failure of immunization may be caused by vaccine-induced or spontaneous 'a' determinant surface gene mutants. Here, we evaluate the possible lack of protection by HBV vaccine, describing the case of an acute hepatitis B diagnosed in a 55-year-old Caucasian male unpaid blood donor, vaccinated against HBV. Sequencing data for preS-S region revealed multiple point mutations. Of all the substitutions found, Q129H, located in the "a" determinant region of HBsAg, can alter antigenicity, leading to mutants. This mutant may cause vaccine failure especially when associated with high viremia of infecting source. Copyright © 2014 Elsevier B.V. All rights reserved.

  16. Antibody induced by immunization with the Jeryl Lynn mumps vaccine strain effectively neutralizes a heterologous wild-type mumps virus associated with a large outbreak.

    Science.gov (United States)

    Rubin, Steven A; Qi, Li; Audet, Susette A; Sullivan, Bradley; Carbone, Kathryn M; Bellini, William J; Rota, Paul A; Sirota, Lev; Beeler, Judy

    2008-08-15

    Recent mumps outbreaks in older vaccinated populations were caused primarily by genotype G viruses, which are phylogenetically distinct from the genotype A vaccine strains used in the countries affected by the outbreaks. This finding suggests that genotype A vaccine strains could have reduced efficacy against heterologous mumps viruses. The remote history of vaccination also suggests that waning immunity could have contributed to susceptibility. To examine these issues, we obtained consecutive serum samples from children at different intervals after vaccination and assayed the ability of these samples to neutralize the genotype A Jeryl Lynn mumps virus vaccine strain and a genotype G wild-type virus obtained during the mumps outbreak that occurred in the United States in 2006. Although the geometric mean neutralizing antibody titers against the genotype G virus were approximately one-half the titers measured against the vaccine strain, and although titers to both viruses decreased with time after vaccination, antibody induced by immunization with the Jeryl Lynn mumps vaccine strain effectively neutralized the outbreak-associated virus at all time points tested.

  17. Genetic diversity of G1P[8] rotavirus VP7 and VP8* antigens in Finland over a 20-year period: No evidence for selection pressure by universal mass vaccination with RotaTeq® vaccine.

    Science.gov (United States)

    Hemming, Maria; Vesikari, Timo

    2013-10-01

    Two live-attenuated oral vaccines (Rotarix™ and Rotateq®) against rotavirus gastroenteritis were licensed in 2006 and have been introduced into National Immunization Programs (NIPs) of several countries. Large scale use of rotavirus vaccines might cause antigenic pressure on circulating rotavirus types or lead to selection of new rotaviruses thus decreasing vaccine efficacy. We examined the nucleotide and amino acid sequences of the surface proteins VP7 and VP4 (cleaved to VP8(*) and VP5(*)) of a total of 108 G1P[8] rotavirus strains collected over a 20-year period from 1992, including the years 2006-2009 when rotavirus vaccine (mainly Rotarix™) was available, and the years 2009-2012 after implementation of RotaTeq® vaccine into the NIP of Finland. In G1 VP7 no changes at amino acid level were observed. In VP8(*) periodical fluctuation of the sublineage over the study period was found with multiple changes both at nucleotide and amino acid levels. Most amino acid changes were in the dominant antigenic epitopes of VP8(*). A change in VP8(*) sublineage occurred between 2008 and 2009, with a temporal correlation to the use of Rotarix™ up to 30% coverage in the period. In contrast, no antigenic changes in the VP8(*) protein appeared to be correlated to the exclusive use of RotaTeq® vaccine after 2009. Nevertheless, long-term surveillance of antigenic changes in VP4 and also VP7 proteins in wild-type rotavirus strains is warranted in countries with large scale use of the currently licensed live oral rotavirus vaccines. Copyright © 2013 Elsevier B.V. All rights reserved.

  18. Perceived concern about the new strain of the influenza and obtaining the vaccine in China, Japan and South Korea.

    Science.gov (United States)

    Kamimura, Akiko; Armenta, Bianca A; Nourian, Maziar M; Wright, Lindsey; Rathi, Naveen; Chernenko, Alla

    This study compares the factors, which influence individuals from the countries of China, Japan and South Korea to obtain any type of influenza vaccines and their perceived concerns about the new strain of the influenza - pandemic (H1N1) 2009. The data analyzed was from the East Asian Social Survey (EASS), Cross-National Survey Data Sets: Health and Society in East Asia, 2010 (ICPSR 34608) (N=7938). The results of this study suggest that individuals who are concerned about the new strain of influenza are more likely to have obtained influenza vaccine. In these countries, perceived concerns may be directly related to vaccine-related behaviors. The results of this study also indicate that there are variations within each country regarding as to why individuals do or do not obtain the influenza vaccine. Over all, this project provides new insights about the acquisition of the influenza vaccine within China, Japan and South Korea, which will be useful for medical practice within these countries and future research. Copyright © 2016 King Saud Bin Abdulaziz University for Health Sciences. Published by Elsevier Ltd. All rights reserved.

  19. The vaccine properties of a Brazilian bovine herpesvirus 1 strain with an induced deletion of the gE gene

    International Nuclear Information System (INIS)

    Franco, A.C.; Spilki, F.R.; Roehe, P.M.; Rijsewijk, F.A.M.

    2005-01-01

    Aiming at the development of a differential vaccine (DIVA) against infectious bovine rhinotracheitis (IBR), a Brazilian strain of bovine herpesvirus type 1 (BHV1) with a deletion of the glycoprotein E (gE) gene was constructed (265gE - ). Here we present the experiments performed with this strain in order to evaluate its safety and efficacy as a vaccine virus in cattle. In the first experiment, a group of calves was inoculated with 265gE - and challenged with wild type virus 21 days post-inoculation. Calves immunized with 265gE - virus and challenged with wild type virus developed very mild clinical disease with a significant reduction in the amount of virus excretion and duration. The safety of the 265gE - during pregnancy was assessed using 22 pregnant cows, at different stages of gestation, that were inoculated with the 265gE - virus intramuscularly, with 15 pregnant cows kept as non-vaccinated controls. No abortions, stillbirths or foetal abnormalities were seen after vaccination. The results show that the 265gE - recombinant is attenuated and able to prevent clinical disease upon challenge. This recombinant will be further evaluated as a candidate virus for a BHV1 differential vaccine. (author)

  20. The characteristics exosporium antigens from different vaccine strains of bacillus antracis

    International Nuclear Information System (INIS)

    Baranova, E.; Biketov, S.; Dunaytsev, I.; Mironova, R.; Dyatlov, I.

    2009-01-01

    To develop of both test-systems for rapid detection and identification of B. anthracis spores and a new subunit vaccine the antigens on the spore surface should be characterized. Exosporium consists of two layers-basal and peripheral and has been form by protein, amino- and neutral polysaccharides, lipids and ash. Number of anthrax exosporium proteins was described and identified: glycoprotein BclA, BclB, alanine racemase, inosine hydrolase, glycosyl hydrolase, superoxid dismutase, ExsF, ExsY, ExsK,CotB,CotY and SoaA. So far no glycosylated proteins other then highly immunogenic glycoproteins BclA, BclB were detected in the B. anthracis spore extract although several exosporium-specific glycoprotein have been described in other members of the B.cereus family- B. thuringiensis and B. cereus. Although EA1 protein originally described as main component of S-layer from vegetative cells he can regular observed in different exosporium preparations and additionally some anti- EA1 monoclonal antibodies able to recognize spore surface. We have revealed that EA1 isolated from spore of Russians strain STI-1contain carbohydrate which determine immunogenicity of this antigen. Because some time ago we have found that exosporium protein's pattern variable among B. anthracis strains we investigated exosporium from spore of different strains of B. anthracis including STI-1, Ames, Stern and others. We have comparative characterized antigens by using Western Blotting, Two-Dimensional electrophoresis and Mass Spec analysis. The results of analysis will be presented and discussed.(author)

  1. Development of a novel vaccine against canine parvovirus infection with a clinical isolate of the type 2b strain

    OpenAIRE

    Park, Seon Ah; Park, Seung-Yong; Song, Chang-Seon; Choi, In-Soo; Kim, Hwi Yool; Lee, Joong-Bok; Lee, Nak-Hyung

    2012-01-01

    Purpose In spite of an extensive vaccination program, parvoviral infections still pose a major threat to the health of dogs. Materials and Methods We isolated a novel canine parvovirus (CPV) strain from a dog with enteritis. Nucleotide and amino acid sequence analysis of the isolate showed that it is a novel type 2b CPV with asparagine at the 426th position and valine at the 555th position in VP2. To develop a vaccine against CPV infection, we passaged the isolate 4 times in A72 cells. Result...

  2. Reactogenicity and immunogenicity of inactivated poliovirus vaccine produced from Sabin strains: a phase I Trial in healthy adults in Cuba.

    Science.gov (United States)

    Resik, Sonia; Tejeda, Alina; Fonseca, Magilé; Alemañi, Nilda; Diaz, Manuel; Martinez, Yenisleidys; Garcia, Gloria; Okayasu, Hiromasa; Burton, Anthony; Bakker, Wilfried A M; Verdijk, Pauline; Sutter, Roland W

    2014-09-22

    To ensure that developing countries have the option to produce inactivated poliovirus vaccine (IPV), the Global Polio Eradication Initiative has promoted the development of an IPV using Sabin poliovirus strains (Sabin IPV). This trial assessed the reactogenicity and immunogenicity of Sabin IPV and adjuvanted Sabin IPV in healthy adults in Cuba. This is a randomized, controlled phase I trial, enrolling 60 healthy (previously vaccinated) male human volunteers, aged 19-23 years to receive one dose of either Sabin IPV (20:32:64 DU/dose), adjuvanted Sabin IPV (10:16:32 DU/dose), or conventional Salk IPV (40:8:32 DU/dose). The primary endpoint for reactogenicity relied on monitoring of adverse events. The secondary endpoint measured boosting immune responses (i.e. seroconversion or 4-fold rise) of poliovirus antibody, assessed by neutralization assays. Sixty subjects fulfilled the study requirements. No serious adverse events reported were attributed to trial interventions during the 6-month follow-up period. Twenty-eight days after vaccination, boosting immune responses against poliovirus types 1-3 were between 90% and 100% in all vaccination groups. There was a more than 6-fold increase in median antibody titers between pre- and post-vaccination titers in all vaccination groups. Both Sabin IPV and adjuvanted Sabin IPV were well tolerated and immunogenic against all poliovirus serotypes. This result suggests that the aluminum adjuvant may allow a 50% (or higher) dose reduction. Copyright © 2014. Published by Elsevier Ltd.

  3. A mammalian cell based FACS-panning platform for the selection of HIV-1 envelopes for vaccine development.

    Directory of Open Access Journals (Sweden)

    Tim-Henrik Bruun

    Full Text Available An increasing number of broadly neutralizing monoclonal antibodies (bnMAb against the HIV-1 envelope (Env protein has been discovered recently. Despite this progress, vaccination efforts with the aim to re-elicit bnMAbs that provide protective immunity have failed so far. Herein, we describe the development of a mammalian cell based FACS-panning method in which bnMAbs are used as tools to select surface-exposed envelope variants according to their binding affinity. For that purpose, an HIV-1 derived lentiviral vector was developed to infect HEK293T cells at low multiplicity of infection (MOI in order to link Env phenotype and genotype. For proof of principle, a gp145 Env model-library was established in which the complete V3 domain was substituted by five strain specific V3 loop sequences with known binding affinities to nMAb 447-52D, respectively. Env genes were recovered from selected cells by PCR, subcloned into a lentiviral vector (i to determine and quantify the enrichment nMAb binders and (ii to generate a new batch of transduction competent particles. After 2 selection cycles the Env variant with highest affinity was enriched 20-fold and represented 80% of the remaining Env population. Exploiting the recently described bnMAbs, this procedure might prove useful in selecting Env proteins from large Env libraries with the potential to elicit bnMAbs when used as vaccine candidates.

  4. Live Vaccine Strain Francisella tularensis is Detectable at the Inoculation Site but Not in Blood after Vaccination Against Tularemia

    National Research Council Canada - National Science Library

    Hepburn, Matthew J; Purcell, Bret K; Lawler, James V; Coyne, Susan R; Petitt, Patricia L; Sellers, Karen D; Norwood, David A; Ulrich, Melanie P

    2006-01-01

    ...) for the detection of F. tularensis in human clinical samples. Methods. Blood and skin swab samples were prospectively collected from volunteers who received the LVS tularemia vaccine at baseline (negative controls...

  5. Concomitant administration of diphtheria, tetanus, acellular pertussis and inactivated poliovirus vaccine derived from Sabin strains (DTaP-sIPV) with pentavalent rotavirus vaccine in Japanese infants.

    Science.gov (United States)

    Tanaka, Yoshiyuki; Yokokawa, Ruriko; Rong, Han Shi; Kishino, Hiroyuki; Stek, Jon E; Nelson, Margaret; Lawrence, Jody

    2017-06-03

    Rotavirus is the leading cause of severe acute gastroenteritis in infants and young children. Most children are infected with rotavirus, and the health and economic burdens of rotavirus gastroenteritis on healthcare systems and families are considerable. In 2012 pentavalent rotavirus vaccine (RV5) and diphtheria, tetanus, acellular pertussis and inactivated poliovirus vaccine derived from Sabin strains (DTaP-sIPV) were licensed in Japan. We examined the immunogenicity and safety of DTaP-sIPV when administrated concomitantly with RV5 in Japanese infants. A total of 192 infants 6 to 11 weeks of age randomized to Group 1 (N = 96) received DTaP-sIPV and RV5 concomitantly, and Group 2 (N = 96) received DTaP-sIPV and RV5 separately. Antibody titer to diphtheria toxin, pertussis antigens (PT and FHA), tetanus toxin, and poliovirus type 1, 2, and 3 were measured at 4 to 6 weeks following 3-doses of DTaP-sIPV. Seroprotection rates for all components of DTaP-sIPV were 100% in both groups, and the geometric mean titers for DTaP-sIPV in Group 1 were comparable to Group 2. Incidence of systemic AEs (including diarrhea, vomiting, fever, and nasopharyngitis) were lower in Group 1 than in Group 2. All vaccine-related AEs were mild or moderate in intensity. There were no vaccine-related serious AEs, no deaths, and no cases of intussusception during the study. Concomitant administration of DTaP-sIPV and RV5 induced satisfactory immune responses to DTaP-sIPV and acceptable safety profile. The administration of DTaP-sIPV given concomitantly with RV5 is expected to facilitate compliance with the vaccination schedule and improve vaccine coverage in Japanese infants.

  6. Stability of live attenuated rotavirus vaccine with selected preservatives and primary containers.

    Science.gov (United States)

    Lal, Manjari; Jarrahian, Courtney; Zhu, Changcheng; Hosken, Nancy A; McClurkan, Chris L; Koelle, David M; Saxon, Eugene; Roehrig, Andrew; Zehrung, Darin; Chen, Dexiang

    2016-05-11

    that was similar to its profile in standard glass vials. This study demonstrates that there are multiple options for the primary container for rotavirus vaccines intended for oral delivery. Selection of an optimal primary container should take into consideration additional factors, including stability as well as cold chain volume, usability, cost, and manufacturing feasibility. Copyright © 2016. Published by Elsevier Ltd.

  7. Differing patterns of selection and geospatial genetic diversity within two leading Plasmodium vivax candidate vaccine antigens.

    Directory of Open Access Journals (Sweden)

    Christian M Parobek

    2014-04-01

    Full Text Available Although Plasmodium vivax is a leading cause of malaria around the world, only a handful of vivax antigens are being studied for vaccine development. Here, we investigated genetic signatures of selection and geospatial genetic diversity of two leading vivax vaccine antigens--Plasmodium vivax merozoite surface protein 1 (pvmsp-1 and Plasmodium vivax circumsporozoite protein (pvcsp. Using scalable next-generation sequencing, we deep-sequenced amplicons of the 42 kDa region of pvmsp-1 (n = 44 and the complete gene of pvcsp (n = 47 from Cambodian isolates. These sequences were then compared with global parasite populations obtained from GenBank. Using a combination of statistical and phylogenetic methods to assess for selection and population structure, we found strong evidence of balancing selection in the 42 kDa region of pvmsp-1, which varied significantly over the length of the gene, consistent with immune-mediated selection. In pvcsp, the highly variable central repeat region also showed patterns consistent with immune selection, which were lacking outside the repeat. The patterns of selection seen in both genes differed from their P. falciparum orthologs. In addition, we found that, similar to merozoite antigens from P. falciparum malaria, genetic diversity of pvmsp-1 sequences showed no geographic clustering, while the non-merozoite antigen, pvcsp, showed strong geographic clustering. These findings suggest that while immune selection may act on both vivax vaccine candidate antigens, the geographic distribution of genetic variability differs greatly between these two genes. The selective forces driving this diversification could lead to antigen escape and vaccine failure. Better understanding the geographic distribution of genetic variability in vaccine candidate antigens will be key to designing and implementing efficacious vaccines.

  8. Vaccination against porcine parvovirus protects against disease, but does not prevent infection and virus shedding after challenge infection with a heterologous virus strain.

    Science.gov (United States)

    Jóźwik, A; Manteufel, J; Selbitz, H-J; Truyen, U

    2009-10-01

    The demonstration of field isolates of porcine parvovirus (PPV) that differ genetically and antigenically from vaccine strains of PPV raises the question of whether the broadly used inactivated vaccines can still protect sows against the novel viruses. Ten specific-pathogen-free primiparous sows were assigned to three groups and were vaccinated with one of two vaccines based on the old vaccine strains, or served as non-vaccinated controls. After insemination, all sows were challenged with the prototype genotype 2 virus, PPV-27a, on gestation day 41; fetuses were delivered on gestation day 90 and examined for virus infection. The fetuses of the vaccinated sows were protected against disease, but both the vaccinated and the non-vaccinated sows showed a marked increase in antibody titres after challenge infection, indicating replication of the challenge virus. All sows (vaccinated and non-vaccinated) shed the challenge virus for at least 10 days after infection, with no difference in the pattern or duration of virus shedding.

  9. Effectiveness of 23-valent pneumococcal polysaccharide vaccine and seasonal influenza vaccine for pneumonia among the elderly - Selection of controls in a case-control study.

    Science.gov (United States)

    Kondo, Kyoko; Suzuki, Kanzo; Washio, Masakazu; Ohfuji, Satoko; Fukushima, Wakaba; Maeda, Akiko; Hirota, Yoshio

    2017-08-24

    We conducted a case-control study to elucidate associations between pneumonia in elderly individuals and 23-valent pneumococcal polysaccharide vaccine (PPSV23) and seasonal influenza vaccine (influenza vaccine). Here, we examined selection of controls in our study using an analytic epidemiology approach. The study period was from October 1, 2009 through September 30, 2014. Cases comprised ≥65-year-old patients newly diagnosed with pneumonia. For every case with pneumonia, two patients with other diseases (one respiratory medicine, one non-respiratory medicine) who were sex-, age-, visit date- and visit hospital-matched were selected as controls. Odds ratios (ORs) and 95% confidence intervals (CIs) of vaccination for pneumonia were calculated using conditional logistic regression model. Similar analyses were also conducted based on the clinical department of controls. Analysis was conducted in 234 cases and 438 controls. Effectiveness of pneumococcal vaccination or influenza vaccination against pneumonia was not detected. Proportions of either vaccination in controls were greater among respiratory medicine (pneumococcal vaccine, 38%; influenza vaccine, 55%) than among non-respiratory medicine (23%; 48%). Analysis using controls restricted to respiratory medicine showed marginally significant effectiveness of pneumococcal vaccination (OR, 0.59; 95%CI, 0.34-1.03; P=0.064) and influenza vaccination (0.64; 0.40-1.04; 0.072). However, this effectiveness might have been overestimated by selection bias of controls, as pneumonia cases are not necessarily respiratory medicine patients. In the analysis using controls restricted to non-respiratory medicine, OR of pneumococcal vaccination for pneumonia was close to 1, presumably because the proportion of pneumococcal vaccination was higher in cases than in controls. Because pneumococcal vaccine was not routinely administered during the study period, differences in recommendations of vaccination by physician in different

  10. Development of a novel vaccine against canine parvovirus infection with a clinical isolate of the type 2b strain.

    Science.gov (United States)

    Park, Seon Ah; Park, Seung-Yong; Song, Chang-Seon; Choi, In-Soo; Kim, Hwi Yool; Lee, Joong-Bok; Lee, Nak-Hyung

    2012-07-01

    In spite of an extensive vaccination program, parvoviral infections still pose a major threat to the health of dogs. We isolated a novel canine parvovirus (CPV) strain from a dog with enteritis. Nucleotide and amino acid sequence analysis of the isolate showed that it is a novel type 2b CPV with asparagine at the 426th position and valine at the 555th position in VP2. To develop a vaccine against CPV infection, we passaged the isolate 4 times in A72 cells. The attenuated isolate conferred complete protection against lethal homologous CPV infection in dogs such that they did not develop any clinical symptoms, and their antibody titers against CPV were significantly high at 7-11 days post infection. These results suggest that the virus isolate obtained after passaging can be developed as a novel vaccine against paroviral infection.

  11. HI responses induced by seasonal influenza vaccination are associated with clinical protection and with seroprotection against non-homologous strains.

    Science.gov (United States)

    Luytjes, Willem; Enouf, Vincent; Schipper, Maarten; Gijzen, Karlijn; Liu, Wai Ming; van der Lubben, Mariken; Meijer, Adam; van der Werf, Sylvie; Soethout, Ernst C

    2012-07-27

    Vaccination against influenza induces homologous as well as cross-specific hemagglutination inhibiting (HI) responses. Induction of cross-specific HI responses may be essential when the influenza strain does not match the vaccine strain, or even to confer a basic immune response against a pandemic influenza virus. We carried out a clinical study to evaluate the immunological responses after seasonal vaccination in healthy adults 18-60 years of age, receiving the yearly voluntary vaccination during the influenza season 2006/2007. Vaccinees of different age groups were followed for laboratory confirmed influenza (LCI) and homologous HI responses as well as cross-specific HI responses against the seasonal H1N1 strain of 2008 and pandemic H1N1 virus of 2009 (H1N1pdm09) were determined. Homologous HI titers that are generally associated with protection (i.e. seroprotective HI titers ≥40) were found in more than 70% of vaccinees. In contrast, low HI titers before and after vaccination were significantly associated with seasonal LCI. Cross-specific HI titers ≥40 against drifted seasonal H1N1 were found in 69% of vaccinees. Cross-specific HI titers ≥40 against H1N1pdm09 were also significantly induced, especially in the youngest age group. More specifically, cross-specific HI titers ≥40 against H1N1pdm09 were inversely correlated with age. We did not find a correlation between the subtype of influenza which was circulating at the age of birth of the vaccinees and cross-specific HI response against H1N1pdm09. These data indicate that the HI titers before and after vaccination determine the vaccination efficacy. In addition, in healthy adults between 18 and 60 years of age, young adults appear to be best able to mount a cross-protective HI response against H1N1pdm09 or drifted seasonal influenza after seasonal vaccination. Copyright © 2012 Elsevier Ltd. All rights reserved.

  12. DIVA vaccine properties of the live chimeric pestivirus strain CP7_E2gif

    DEFF Research Database (Denmark)

    von Rosen, Tanya; Rangelova, Desislava Yordanova; Nielsen, Jens

    2014-01-01

    Live modified vaccines to protect against classical swine fever virus (CSFV), based on chimeric pestiviruses, have been developed to enable serological Differentiation of Infected from Vaccinated Animals (DIVA). In this context, the chimeric virus CP7_E2gif vaccine candidate is unique as it does...

  13. Construction and evaluation of Bordetella pertussis live attenuated vaccine strain BPZE1 producing Fim3.

    NARCIS (Netherlands)

    Debrie, Anne-Sophie; Coutte, Loïc; Raze, Dominique; Mooi, Frits; Alexander, Frances; Gorringe, Andrew; Mielcarek, Nathalie; Locht, Camille

    2018-01-01

    Pertussis or whooping cough is currently the most prevalent vaccine-preventable childhood disease despite >85% global vaccination coverage. In recent years incidence has greatly increased in several high-income countries that have switched from the first-generation, whole-cell vaccine to the newer

  14. Methyltransferase-defective avian metapneumovirus vaccines provide complete protection against challenge with the homologous Colorado strain and the heterologous Minnesota strain.

    Science.gov (United States)

    Sun, Jing; Wei, Yongwei; Rauf, Abdul; Zhang, Yu; Ma, Yuanmei; Zhang, Xiaodong; Shilo, Konstantin; Yu, Qingzhong; Saif, Y M; Lu, Xingmeng; Yu, Lian; Li, Jianrong

    2014-11-01

    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. Since its discovery in the 1970s, aMPV has been recognized as an economically important pathogen in the poultry industry worldwide. The conserved region VI (CR VI) of the large (L) polymerase proteins of paramyxoviruses catalyzes methyltransferase (MTase) activities that typically methylate viral mRNAs at guanine N-7 (G-N-7) and ribose 2'-O positions. In this study, we generated a panel of recombinant aMPV (raMPV) Colorado strains carrying mutations in the S-adenosyl methionine (SAM) binding site in the CR VI of L protein. These recombinant viruses were specifically defective in ribose 2'-O, but not G-N-7 methylation and were genetically stable and highly attenuated in cell culture and viral replication in the upper and lower respiratory tracts of specific-pathogen-free (SPF) young turkeys. Importantly, turkeys vaccinated with these MTase-defective raMPVs triggered a high level of neutralizing antibody and were completely protected from challenge with homologous aMPV Colorado strain and heterologous aMPV Minnesota strain. Collectively, our results indicate (i) that aMPV lacking 2'-O methylation is highly attenuated in vitro and in vivo and (ii) that inhibition of mRNA cap MTase can serve as a novel target to rationally design live attenuated vaccines for aMPV and perhaps other paramyxoviruses. Paramyxoviruses include many economically and agriculturally important viruses such as avian metapneumovirus (aMPV), and Newcastle disease virus (NDV), human pathogens such as human respiratory syncytial virus, human metapneumovirus, human parainfluenza virus type 3, and measles virus, and highly lethal emerging pathogens such as Nipah virus and Hendra virus. For many of them, there is no effective vaccine or antiviral drug. These viruses share common strategies for viral gene

  15. Hepatitis B vaccination coverage and the determinants of vaccination among health care workers in selected health facilities in Lusaka district, Zambia: an exploratory study.

    Science.gov (United States)

    Mungandi, Namwaka; Makasa, Mpundu; Musonda, Patrick

    2017-01-01

    Hepatitis B is a viral infection of the liver and causes both acute and chronic disease. It is transmitted through contact with an infected person's bodily fluids. It is an occupational hazard for healthcare workers and can be prevented by the administration of a vaccine. It is recommended that healthcare workers be vaccinated against vaccine preventable diseases including hepatitis B. The study objective was to determine the prevalence and determinants of hepatitis B vaccination among healthcare workers in selected health facilities in Lusaka. The study took place in seven health facilities across Lusaka district in Zambia. A total sample size of 331 healthcare workers was selected of which; 90 were nurses, 88 were doctors, 86 were laboratory personnel and 67 were general workers. A self-administered structured questionnaire was given to a total of 331 healthcare workers. Investigator led stepwise approach was used to select the best predictor variables in a multiple logistic regression model and all analyses were performed using STATA software, version 12.1 SE (Stata Corporation, College Station, TX, USA). Only 64(19.3%) of the healthcare workers were vaccinated against hepatitis B, with 35 (54.7%) of these being fully vaccinated and 29 (45.3%) partially vaccinated. Analysis showed that; age of the healthcare worker, sharp injuries per year and training in infection control were the variables that were statistically significant in predicting a healthcare worker's vaccination status. It is reassuring to learn that healthcare workers have knowledge regarding hepatitis B and the vaccine and are willing to be vaccinated against it. Health institutions should bear the cost for vaccinating staff and efforts should be made for appropriate health education regarding hepatitis B infection and its prevention. Establishment of policies on compulsory hepatitis B vaccination for healthcare workers in Zambia is recommended.

  16. Evaluation of the thermal stability of a novel strain of live-attenuated mumps vaccine (RS-12 strain) lyophilized in different stabilizers.

    Science.gov (United States)

    Jamil, Razieh Kamali; Taqavian, Mohammad; Sadigh, Zohreh-Azita; Shahkarami, Mohammad-Kazem; Esna-Ashari, Fatemeh; Hamkar, Rasool; Hosseini, Seyedeh-Marzieh; Hatami, Alireza

    2014-04-01

    The stability of live-attenuated viral vaccines is important for immunization efficacy. Here, the thermostabilities of lyophilized live-attenuated mumps vaccine formulations in two different stabilizers, a trehalose dihydrate-based stabilizer and a stabilizer containing sucrose, human serum albumin and sorbitol were investigated using accelerated stability tests at 4°C, 25°C and 37°C at time points between 4h (every 4h for the first 24h) and 1 week. Even under the harshest storage conditions of 37°C for 1 week, the 50% cell culture infective dose (CCID50) determined from titrations in Vero cells dropped by less than 10-fold using each stabilizer formulation and thus complied with the World Health Organization's requirements for the potency of live-attenuated mumps vaccines. However, as the half-life of the RS-12 strain mumps virus infectivity was lengthened substantially at elevated temperatures using the trehalose dihydrate (TD)-based stabilizer, this stabilizer is recommended for vaccine use. Copyright © 2013 Elsevier B.V. All rights reserved.

  17. Mead production: selection and characterization assays of Saccharomyces cerevisiae strains.

    Science.gov (United States)

    Pereira, Ana Paula; Dias, Teresa; Andrade, João; Ramalhosa, Elsa; Estevinho, Letícia M

    2009-08-01

    Mead is a traditional drink, which results from the alcoholic fermentation of diluted honey carried out by yeasts. However, when it is produced in a homemade way, mead producers find several problems, namely, the lack of uniformity in the final product, delayed and arrested fermentations, and the production of "off-flavours" by the yeasts. These problems are usually associated with the inability of yeast strains to respond and adapt to unfavourable and stressful growth conditions. The main objectives of this work were to evaluate the capacity of Saccharomyces cerevisiae strains, isolated from honey of the Trás-os-Montes (Northeast Portugal), to produce mead. Five strains from honey, as well as one laboratory strain and one commercial wine strain, were evaluated in terms of their fermentation performance under ethanol, sulphur dioxide and osmotic stress. All the strains showed similar behaviour in these conditions. Two yeasts strains isolated from honey and the commercial wine strain were further tested for mead production, using two different honey (a dark and a light honey), enriched with two supplements (one commercial and one developed by the research team), as fermentation media. The results obtained in this work show that S. cerevisiae strains isolated from honey, are appropriate for mead production. However it is of extreme importance to take into account the characteristics of the honey, and supplements used in the fermentation medium formulation, in order to achieve the best results in mead production.

  18. Molecular characterization of rotavirus strains detected during a clinical trial of a human rotavirus vaccine in Blantyre, Malawi.

    Science.gov (United States)

    Nakagomi, Toyoko; Nakagomi, Osamu; Dove, Winifred; Doan, Yen Hai; Witte, Desiree; Ngwira, Bagrey; Todd, Stacy; Duncan Steele, A; Neuzil, Kathleen M; Cunliffe, Nigel A

    2012-04-27

    The human, G1P[8] rotavirus vaccine (Rotarix™) significantly reduced severe rotavirus gastroenteritis episodes in a clinical trial in South Africa and Malawi, but vaccine efficacy was lower in Malawi (49.5%) than reported in South Africa (76.9%) and elsewhere. The aim of this study was to examine the molecular relationships of circulating wild-type rotaviruses detected during the clinical trial in Malawi to RIX4414 (the strain contained in Rotarix™) and to common human rotavirus strains. Of 88 rotavirus-positive, diarrhoeal stool specimens, 43 rotaviruses exhibited identifiable RNA migration patterns when examined by polyacrylamide gel electrophoresis. The genes encoding VP7, VP4, VP6 and NSP4 of 5 representative strains possessing genotypes G12P[6], G1P[8], G9P[8], and G8P[4] were sequenced. While their VP7 (G) and VP4 (P) genotype designations were confirmed, the VP6 (I) and NSP4 (E) genotypes were either I1E1 or I2E2, indicating that they were of human rotavirus origin. RNA-RNA hybridization using 21 culture-adapted strains showed that Malawian rotaviruses had a genomic RNA constellation common to either the Wa-like or the DS-1 like human rotaviruses. Overall, the Malawi strains appear similar in their genetic make-up to rotaviruses described in countries where vaccine efficacy is greater, suggesting that the lower efficacy in Malawi is unlikely to be explained by the diversity of circulating strains. Copyright © 2011 Elsevier Ltd. All rights reserved.

  19. Identification of a consistent pattern of mutations in neurovirulent variants derived from the sabin vaccine strain of poliovirus type 2.

    OpenAIRE

    Equestre, M; Genovese, D; Cavalieri, F; Fiore, L; Santoro, R; Perez Bercoff, R

    1991-01-01

    Complete nucleotide sequencing of the RNAs of two unrelated neurovirulent isolates of Sabin-related poliovirus type 2 revealed that two nucleotides and one amino acid (amino acid 143 in the major capsid protein VP1) consistently departed from the sequences of the nonneurovirulent poliovirus type 2 712 and Sabin vaccine strains. This pattern of mutation appeared to be a feature common to all neurovirulent variants of poliovirus type 2.

  20. Protection of pigs against challenge with virulent Streptococcus suis serotype 2 strains by a muramidase-released protein and extracellular factor vaccine

    NARCIS (Netherlands)

    Wisselink, H.J.; Vecht, U.; Stockhofe Zurwieden, N.; Smith, H.E.

    2001-01-01

    The efficacy of a muramidase-released protein (MRP) and extracellular factor (EF) vaccine in preventing infection and disease in pigs challenged either with a homologous or a heterologous Streptococcus suis serotype 2 strain (MRP EF ) was compared with the efficacy of a vaccine containing

  1. Evaluation of yellow fever virus 17D strain as a new vector for HIV-1 vaccine development.

    Science.gov (United States)

    Franco, David; Li, Wenjing; Qing, Fang; Stoyanov, Cristina T; Moran, Thomas; Rice, Charles M; Ho, David D

    2010-08-09

    The failure to develop an effective vaccine against HIV-1 infection has led the research community to seek new ways of raising qualitatively different antibody and cellular immune responses. Towards this goal, we investigated the yellow fever 17D vaccine strain (YF17D), one of the most effective vaccines ever made, as a platform for HIV-1 vaccine development. A test antigen, HIV-1 p24 (clade B consensus), was inserted near the 5' end of YF17D, in frame and upstream of the polyprotein (YF-5'/p24), or between the envelope and the first non-structural protein (YF-E/p24/NS1). In vitro characterization of these recombinants indicated that the gene insert was more stable in the context of YF-E/p24/NS1. This was confirmed in immunogenicity studies in mice. CD8(+) IFN-gamma T-cell responses against p24 were elicited by the YF17D recombinants, as were specific CD4(+) T cells expressing IFN-gamma and IL-2. A balanced CD4(+) and CD8(+) T-cell response was notable, as was the polyfunctionality of the responding cells. Finally, the protective efficacy of the YF17D recombinants, particularly YF-E/p24/NS1, in mice challenged with a vaccinia expressing HIV-1 Gag was demonstrated. These results suggest that YF17D warrants serious consideration as a live-attenuated vector for HIV-1 vaccine development. Copyright 2010 Elsevier Ltd. All rights reserved.

  2. Recombinant infectious bronchitis virus (IBV) H120 vaccine strain expressing the hemagglutinin-neuraminidase (HN) protein of Newcastle disease virus (NDV) protects chickens against IBV and NDV challenge.

    Science.gov (United States)

    Yang, Xin; Zhou, Yingshun; Li, Jianan; Fu, Li; Ji, Gaosheng; Zeng, Fanya; Zhou, Long; Gao, Wenqian; Wang, Hongning

    2016-05-01

    Infectious bronchitis (IB) and Newcastle disease (ND) are common viral diseases of chickens, which are caused by infectious bronchitis virus (IBV) and Newcastle disease virus (NDV), respectively. Vaccination with live attenuated strains of IBV-H120 and NDV-LaSota are important for the control of IB and ND. However, conventional live attenuated vaccines are expensive and result in the inability to differentiate between infected and vaccinated chickens. Therefore, there is an urgent need to develop new efficacious vaccines. In this study, using a previously established reverse genetics system, we generated a recombinant IBV virus based on the IBV H120 vaccine strain expressing the haemagglutinin-neuraminidase (HN) protein of NDV. The recombinant virus, R-H120-HN/5a, exhibited growth dynamics, pathogenicity and viral titers that were similar to those of the parental IBV H120, but it had acquired hemagglutination activity from NDV. Vaccination of SPF chickens with the R-H120-HN/5a virus induced a humoral response at a level comparable to that of the LaSota/H120 commercial bivalent vaccine and provided significant protection against challenge with virulent IBV and NDV. In summary, the results of this study indicate that the IBV H120 strain could serve as an effective tool for designing vaccines against IB and other infectious diseases, and the generation of IBV R-H120-HN/5a provides a solid foundation for the development of an effective bivalent vaccine against IBV and NDV.

  3. Clostridium difficile chimeric toxin receptor binding domain vaccine induced protection against different strains in active and passive challenge models.

    Science.gov (United States)

    Tian, Jing-Hui; Glenn, Gregory; Flyer, David; Zhou, Bin; Liu, Ye; Sullivan, Eddie; Wu, Hua; Cummings, James F; Elllingsworth, Larry; Smith, Gale

    2017-07-24

    Clostridium difficile is the number one cause of nosocomial antibiotic-associated diarrhea in developed countries. Historically, pathogenesis was attributed two homologous glucosylating toxins, toxin-A (TcdA) and toxin-B (TcdB). Over the past decade, however, highly virulent epidemic strains of C. difficile (B1/NAP1/027) have emerged and are linked to an increase in morbidity and mortality. Increased virulence is attributed to multiple factors including: increased production of A- and B-toxins; production of binary toxin (CDT); and the emergence of more toxic TcdB variants (TcdB (027) ). TcdB (027) is more cytotoxicity to cells; causes greater tissue damage and toxicity in animals; and is antigenically distinct from historical TcdB (TcdB (003) ). Broadly protective vaccines and therapeutic antibody strategies, therefore, may target TcdA, TcdB variants and CDT. To facilitate the generation of multivalent toxin-based C. difficile vaccines and therapeutic antibodies, we have generated fusion proteins constructed from the receptor binding domains (RBD) of TcdA, TcdB (003) , TcdB (027) and CDT. Herein, we describe the development of a trivalent toxin (T-toxin) vaccine (CDTb/TcdB (003) /TcdA) and quadravalent toxin (Q-toxin) vaccine (CDTb/TcB (003) /TcdA/TcdB (027) ) fusion proteins that retain the protective toxin neutralizing epitopes. Active immunization of mice or hamsters with T-toxin or Q-toxin fusion protein vaccines elicited the generation of toxin neutralizing antibodies to each of the toxins. Hamsters immunized with the Q-toxin vaccine were broadly protected against spore challenge with historical C. difficile 630 (toxinotype 0/ribotype 003) and epidemic NAP1 (toxinotype III/ribotype 027) strains. Fully human polyclonal antitoxin IgG was produced by immunization of transgenic bovine with these fusion proteins. In passive transfer studies, mice were protected against lethal toxin challenge. Hamsters treated with human antitoxin IgG were completely protected when

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

    Science.gov (United States)

    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

  5. [VACCINES].

    Science.gov (United States)

    Bellver Capella, Vincente

    2015-10-01

    Vaccines are an extraordinary instrument of immunization of the population against infectious diseases. Around them there are many ethical issues. One of the most debated is what to do with certain groups opposition to vaccination of their children. States have managed in different ways the conflict between the duty of vaccination and the refusal to use vaccines: some impose the vaccination and others simply promote it. In this article we deal with which of these two approaches is the most suitable from an ethical and legal point of view. We stand up for the second option, which is the current one in Spain, and we propose some measures which should be kept in mind to improve immunization programs.

  6. Rapid and Reliable Single Nucleotide Polymorphism-Based Differentiation of Brucella Live Vaccine Strains from Field Strains

    Science.gov (United States)

    Brucellosis is a major zoonotic disease responsible for substantial social and economic problems, particularly in the developing world. One element that can implemented as part of control programs tackling animal disease is the use of one of the OIE recommended vaccines to protect against either Bru...

  7. 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.

    Science.gov (United States)

    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.

  8. Real-time reverse transcription polymerase chain reaction method for detection of Canine distemper virus modified live vaccine shedding for differentiation from infection with wild-type strains.

    Science.gov (United States)

    Wilkes, Rebecca P; Sanchez, Elena; Riley, Matthew C; Kennedy, Melissa A

    2014-01-01

    Canine distemper virus (CDV) remains a common cause of infectious disease in dogs, particularly in high-density housing situations such as shelters. Vaccination of all dogs against CDV is recommended at the time of admission to animal shelters and many use a modified live virus (MLV) vaccine. From a diagnostic standpoint for dogs with suspected CDV infection, this is problematic because highly sensitive diagnostic real-time reverse transcription polymerase chain reaction (RT-PCR) tests are able to detect MLV virus in clinical samples. Real-time PCR can be used to quantitate amount of virus shedding and can differentiate vaccine strains from wild-type strains when shedding is high. However, differentiation by quantitation is not possible in vaccinated animals during acute infection, when shedding is low and could be mistaken for low level vaccine virus shedding. While there are gel-based RT-PCR assays for differentiation of vaccine strains from field strains based on sequence differences, the sensitivity of these assays is unable to match that of the real-time RT-PCR assay currently used in the authors' laboratory. Therefore, a real-time RT-PCR assay was developed that detects CDV MLV vaccine strains and distinguishes them from wild-type strains based on nucleotide sequence differences, rather than the amount of viral RNA in the sample. The test is highly sensitive, with detection of as few as 5 virus genomic copies (corresponding to 10(-1) TCID(50)). Sequencing of the DNA real-time products also allows phylogenetic differentiation of the wild-type strains. This test will aid diagnosis during outbreaks of CDV in recently vaccinated animals.

  9. Cross-protective efficacy of engineering serotype A foot-and-mouth disease virus vaccine against the two pandemic strains in swine.

    Science.gov (United States)

    Zheng, Haixue; Lian, Kaiqi; Yang, Fan; Jin, Ye; Zhu, Zixiang; Guo, Jianhong; Cao, Weijun; Liu, Huanan; He, Jijun; Zhang, Keshan; Li, Dan; Liu, Xiangtao

    2015-10-26

    Foot-and-mouth disease (FMD) is a highly contagious vesicular disease that affects domestic and wild cloven-hoofed animals worldwide. Recently, a series of outbreaks of type A FMDV occurred in Southeast Asian countries, China, the Russia Federation, Mongolia, Kazakhstan and South Korea. The FMD virus (A/GDMM/CHA/2013) from China's Guangdong province (2013) is representative of those responsible for the latest epidemic, and has low amino acid identity (93.9%) in VP1 protein with the epidemic strain A/WH/CHA/09 from Wuhan, China in 2009. Both of isolates belong to the Sea-97 genotype of ASIA topotype. Therefore, the application of a new vaccine strain with cross-protective efficacy is of fundamental importance to control the spread of the two described pandemic strains. A chimeric strain rA/P1-FMDV constructed by our lab previously through replacing the P1 gene in the vaccine strain O/CHA/99 with that from the epidemic stain A/WH/CHA/09, has been demonstrated to exhibit good growth characteristics in culture, and the rA/P1-FMDV inactivated vaccine can provide protection against epidemic strain A/WH/CHA/09 in cattle. However, it is still unclear whether the vaccine produces efficient protection against the new pandemic strain (A/GDMM/CHA/2013). Here, vaccine matching and pig 50% protective dose (PD50) tests were performed to assess the vaccine potency. The vaccine matching test showed cross-reactivity of sera from full dose vaccine vaccinated pigs with A/WH/CHA/09 and A/GDMM/CHA/2013 isolates, with average r1 values of 0.94±0.12 and 0.68±0.06 (r1≥0.3), which indicates that the rA/P1-FMDV vaccine is likely to confer good cross-protection against the two isolates. When challenged with two pandemic isolates A/WH/CHA/09 and A/GDMM/CHA/2013 strain, the vaccine achieved 12.51 PD50 and 10.05 PD50 per dose (2.8μg), respectively. The results indicated that the rA/P1-FMDV inactivated vaccine could protect pigs against both A/WH/CHA/09 and A/GDMM/CHA/2013 pandemic isolates

  10. Improved OMV vaccine against Neisseria meningitidis using genetically engineered strains and a detergent-free purification process

    NARCIS (Netherlands)

    Waterbeemd, van de B.; Streefland, M.; Ley, de P.; Zomer, B.; Dijken, van H.; Martens, D.E.; Wijffels, R.H.; Pol, van der L.A.

    2010-01-01

    The use of detergent-extracted outer membrane vesicles (OMVs) is an established approach for development of a multivalent PorA vaccine against N. meningitidis serogroup B. Selective removal of lipopolysaccharide (LPS) decreases toxicity, but promotes aggregation and narrows the immune response.

  11. Rotavirus vaccines

    Directory of Open Access Journals (Sweden)

    Kang G

    2006-01-01

    Full Text Available Rotavirus, the most common cause of severe diarrhea and a leading cause of mortality in children, has been a priority target for vaccine development for the past several years. The first rotavirus vaccine licensed in the United States was withdrawn because of an association of the vaccine with intussusception. However, the need for a vaccine is greatest in the developing world, because the benefits of preventing deaths due to rotavirus disease are substantially greater than the risk of intussusception. Early vaccines were based on animal strains. More recently developed and licenced vaccines are either animal-human reassortants or are based on human strains. In India, two candidate vaccines are in the development process, but have not yet reached efficacy trials. Many challenges regarding vaccine efficacy and safety remain. In addition to completing clinical evaluations of vaccines in development in settings with the highest disease burden and virus diversity, there is also a need to consider alternative vaccine development strategies.

  12. A multiplex reverse transcription-nested polymerase chain reaction for detection and differentiation of wild-type and vaccine strains of canine distemper virus

    Directory of Open Access Journals (Sweden)

    Cui Shang-jin

    2010-05-01

    Full Text Available Abstract A multiplex reverse transcription-nested polymerase chain reaction (RT-nPCR method was developed for the detection and differentiation of wild-type and vaccine strains of canine distemper virus (CDV. A pair of primers (P1 and P4 specific for CDV corresponding to the highly conserved region of the CDV genome were used as a common primer pair in the first-round PCR of the nested PCR. Primers P2 specific for CDV wild-type strains, were used as the forward primer together with the common reverse primer P4 in the second round of nested PCR. Primers P3, P5 specific for CDV wild-type strain or vaccine strain, were used as the forward primer together with the common reverse primer P4+P6 in the second round of nested PCR. A fragment of 177 bp was amplified from vaccine strain genomic RNA, and a fragment of 247 bp from wild-type strain genomic RNA in the RT-nPCR, and two fragments of 247 bp and 177 bp were amplified from the mixed samples of vaccine and wild-type strains. No amplification was achieved for uninfected cells, or cells infected with Newcastle disease virus (NDV, canine parvovirus (CPV, canine coronavirus (CCV, rabies virus (RV, or canine adenovirus (CAV. The RT-nPCR method was used to detect 30 field samples suspected of canine distemper from Heilongjiang and Jilin Provinces, and 51 samples in Shandong province. As a result of 30 samples, were found to be wild-type-like, and 5 to be vaccine-strain-like. The RT-nPCR method can be used to effectively detect and differentiate wild-type CDV-infected dogs from dogs vaccinated with CDV vaccine, and thus can be used in clinical detection and epidemiological surveillance.

  13. A multiplex reverse transcription-nested polymerase chain reaction for detection and differentiation of wild-type and vaccine strains of canine distemper virus

    Science.gov (United States)

    2010-01-01

    A multiplex reverse transcription-nested polymerase chain reaction (RT-nPCR) method was developed for the detection and differentiation of wild-type and vaccine strains of canine distemper virus (CDV). A pair of primers (P1 and P4) specific for CDV corresponding to the highly conserved region of the CDV genome were used as a common primer pair in the first-round PCR of the nested PCR. Primers P2 specific for CDV wild-type strains, were used as the forward primer together with the common reverse primer P4 in the second round of nested PCR. Primers P3, P5 specific for CDV wild-type strain or vaccine strain, were used as the forward primer together with the common reverse primer P4+P6 in the second round of nested PCR. A fragment of 177 bp was amplified from vaccine strain genomic RNA, and a fragment of 247 bp from wild-type strain genomic RNA in the RT-nPCR, and two fragments of 247 bp and 177 bp were amplified from the mixed samples of vaccine and wild-type strains. No amplification was achieved for uninfected cells, or cells infected with Newcastle disease virus (NDV), canine parvovirus (CPV), canine coronavirus (CCV), rabies virus (RV), or canine adenovirus (CAV). The RT-nPCR method was used to detect 30 field samples suspected of canine distemper from Heilongjiang and Jilin Provinces, and 51 samples in Shandong province. As a result of 30 samples, were found to be wild-type-like, and 5 to be vaccine-strain-like. The RT-nPCR method can be used to effectively detect and differentiate wild-type CDV-infected dogs from dogs vaccinated with CDV vaccine, and thus can be used in clinical detection and epidemiological surveillance. PMID:20433759

  14. Vaccine and Wild-Type Strains of Yellow Fever Virus Engage Distinct Entry Mechanisms and Differentially Stimulate Antiviral Immune Responses.

    Science.gov (United States)

    Fernandez-Garcia, Maria Dolores; Meertens, Laurent; Chazal, Maxime; Hafirassou, Mohamed Lamine; Dejarnac, Ophélie; Zamborlini, Alessia; Despres, Philippe; Sauvonnet, Nathalie; Arenzana-Seisdedos, Fernando; Jouvenet, Nolwenn; Amara, Ali

    2016-02-09

    The live attenuated yellow fever virus (YFV) vaccine 17D stands as a "gold standard" for a successful vaccine. 17D was developed empirically by passaging the wild-type Asibi strain in mouse and chicken embryo tissues. Despite its immense success, the molecular determinants for virulence attenuation and immunogenicity of the 17D vaccine are poorly understood. 17D evolved several mutations in its genome, most of which lie within the envelope (E) protein. Given the major role played by the YFV E protein during virus entry, it has been hypothesized that the residues that diverge between the Asibi and 17D E proteins may be key determinants of attenuation. In this study, we define the process of YFV entry into target cells and investigate its implication in the activation of the antiviral cytokine response. We found that Asibi infects host cells exclusively via the classical clathrin-mediated endocytosis, while 17D exploits a clathrin-independent pathway for infectious entry. We demonstrate that the mutations in the 17D E protein acquired during the attenuation process are sufficient to explain the differential entry of Asibi versus 17D. Interestingly, we show that 17D binds to and infects host cells more efficiently than Asibi, which culminates in increased delivery of viral RNA into the cytosol and robust activation of the cytokine-mediated antiviral response. Overall, our study reveals that 17D vaccine and Asibi enter target cells through distinct mechanisms and highlights a link between 17D attenuation, virus entry, and immune activation. The yellow fever virus (YFV) vaccine 17D is one of the safest and most effective live virus vaccines ever developed. The molecular determinants for virulence attenuation and immunogenicity of 17D are poorly understood. 17D was generated by serially passaging the virulent Asibi strain in vertebrate tissues. Here we examined the entry mechanisms engaged by YFV Asibi and the 17D vaccine. We found the two viruses use different entry

  15. Construction of a full-length infectious bacterial artificial chromosome clone of duck enteritis virus vaccine strain

    Science.gov (United States)

    2013-01-01

    Background Duck enteritis virus (DEV) is the causative agent of duck viral enteritis, which causes an acute, contagious and lethal disease of many species of waterfowl within the order Anseriformes. In recent years, two laboratories have reported on the successful construction of DEV infectious clones in viral vectors to express exogenous genes. The clones obtained were either created with deletion of viral genes and based on highly virulent strains or were constructed using a traditional overlapping fosmid DNA system. Here, we report the construction of a full-length infectious clone of DEV vaccine strain that was cloned into a bacterial artificial chromosome (BAC). Methods A mini-F vector as a BAC that allows the maintenance of large circular DNA in E. coli was introduced into the intergenic region between UL15B and UL18 of a DEV vaccine strain by homologous recombination in chicken embryoblasts (CEFs). Then, the full-length DEV clone pDEV-vac was obtained by electroporating circular viral replication intermediates containing the mini-F sequence into E. coli DH10B and identified by enzyme digestion and sequencing. The infectivity of the pDEV-vac was validated by DEV reconstitution from CEFs transfected with pDEV-vac. The reconstructed virus without mini-F vector sequence was also rescued by co-transfecting the Cre recombinase expression plasmid pCAGGS-NLS/Cre and pDEV-vac into CEF cultures. Finally, the in vitro growth properties and immunoprotection capacity in ducks of the reconstructed viruses were also determined and compared with the parental virus. Results The full genome of the DEV vaccine strain was successfully cloned into the BAC, and this BAC clone was infectious. The in vitro growth properties of these reconstructions were very similar to parental DEV, and ducks immunized with these viruses acquired protection against virulent DEV challenge. Conclusions DEV vaccine virus was cloned as an infectious bacterial artificial chromosome maintaining full

  16. Predicted Strain Coverage of a New Meningococcal Multicomponent Vaccine (4CMenB in Spain: Analysis of the Differences with Other European Countries.

    Directory of Open Access Journals (Sweden)

    Raquel Abad

    Full Text Available A novel meningococcal multicomponent vaccine, 4CMenB (Bexsero®, has been approved in Europe, Canada, Australia and US. The potential impact of 4CMenB on strain coverage is being estimated by using Meningococcal Antigen Typing System (MATS, an ELISA assay which measures vaccine antigen expression and diversity in each strain. Here we show the genetic characterization and the 4CMenB potential coverage of Spanish invasive strains (collected during one epidemiological year compared to other European countries and discuss the potential reasons for the lower estimate of coverage in Spain.A panel of 300 strains, a representative sample of all serogroup B Neisseria meningitidis notified cases in Spain from 2009 to 2010, was characterized by multilocus sequence typing (MLST and FetA variable region determination. 4CMenB vaccine antigens, PorA, factor H binding protein (fHbp, Neisseria Heparin Binding Antigen (NHBA and Neisserial adhesin A (NadA were molecularly typed by sequencing. PorA coverage was assigned to strain with VR2 = 4. The levels of expression and cross-reactivity of fHbp, NHBA and NadA were analyzed using MATS ELISA.Global estimated strain coverage by MATS was 68.67% (95% CI: 47.77-84.59%, with 51.33%, 15.33% and 2% of strains covered by one, two and three vaccine antigens, respectively. The predicted strain coverage by individual antigens was: 42% NHBA, 36.33% fHbp, 8.33% PorA and 1.33% NadA. Coverage within the most prevalent clonal complexes (cc was 70.37% for cc 269, 30.19% for cc 213 and 95.83% for cc 32.Clonal complexes (cc distribution accounts for variations in strain coverage, so that country-by-country investigations of strain coverage and cc prevalence are important. Because the cc distribution could also vary over time, which in turn could lead to changes in strain coverage, continuous detailed surveillance and monitoring of vaccine antigens expression is needed in those countries where the multicomponent vaccine is introduced

  17. Immune responses to recombinants of the South African vaccine strain of lumpy skin disease virus generated by using thymidine kinase gene insertion.

    Science.gov (United States)

    Wallace, David B; Viljoen, Gerrit J

    2005-04-27

    The South African vaccine strain of lumpy skin disease virus (type SA-Neethling) is currently being developed as a vector for recombinant vaccines of economically important livestock diseases throughout Africa. In this study, the feasibility of using the viral thymidine kinase gene as the site of insertion was investigated and recombinant viruses were evaluated in animal trials. Two separate recombinants were generated and selected for homogeneity expressing either the structural glycoprotein gene of bovine ephemeral fever virus (BEFV) or the two structural glycoprotein genes of Rift Valley fever virus (RVFV). Both recombinants incorporate the enhanced green fluorescent protein (EGFP) as a visual marker and the Escherichia coli guanine phosphoribosyl transferase (gpt) gene for dominant positive selection. The LSDV-RVFV recombinant construct (rLSDV-RVFV) protected mice against virulent RVFV challenge. In a small-scale BEFV-challenge cattle trial the rLSDV-BEFV construct failed to fully protect the cattle against virulent challenge, although both a humoral and cellular BEFV-specific immune response was elicited.

  18. An outbreak of mumps with genetic strain variation in a highly vaccinated student population in Scotland.

    Science.gov (United States)

    Willocks, L J; Guerendiain, D; Austin, H I; Morrison, K E; Cameron, R L; Templeton, K E; DE Lima, V R F; Ewing, R; Donovan, W; Pollock, K G J

    2017-11-01

    An outbreak of mumps within a student population in Scotland was investigated to assess the effect of previous vaccination on infection and clinical presentation, and any genotypic variation. Of the 341 cases, 79% were aged 18-24. Vaccination status was available for 278 cases of whom 84% had received at least one dose of mumps containing vaccine and 62% had received two. The complication rate was 5·3% (mainly orchitis), and 1·2% were admitted to hospital. Genetic sequencing of mumps virus isolated from cases across Scotland classified 97% of the samples as genotype G. Two distinct clusters of genotype G were identified, one circulating before the outbreak and the other thereafter, suggesting the virus that caused this outbreak was genetically different from the previously circulating virus. Whilst the poor vaccine effectiveness we found may be due to waning immunity over time, a contributing factor may be that the current mumps vaccine is less effective against some genotypes. Although the general benefits of the measles-mumps-rubella (MMR) vaccine should continue to be promoted, there may be value in reassessing the UK vaccination schedule and the current mumps component of the MMR vaccine.

  19. Annually repeated influenza vaccination improves humoral responses to several influenza virus strains in healthy elderly

    NARCIS (Netherlands)

    I.A. de Bruijn (Iris); E.J. Remarque (Edmond); W.E.Ph. Beyer (Walter); S. le Cessie (Saskia); N. Masurel (Nic); G.L. Ligthart (Gerard)

    1997-01-01

    textabstractThe benefit of annually repeated influenza vaccination on antibody formation is still under debate. In this study the effect of annually repeated influenza vaccination on haemagglutination inhibiting (HI) antibody formation in the elderly is investigated. Between 1990 and 1993 healthy

  20. Development, validation and field evaluation of a quantitative real-time PCR able to differentiate between field Mycoplasma synoviae and the MS-H-live vaccine strain.

    Science.gov (United States)

    Dijkman, R; Feberwee, A; Landman, W J M

    2017-08-01

    A quantitative PCR (qPCR) able to differentiate between field Mycoplasma synoviae and MS-H vaccine strain was developed, validated and evaluated. It was developed using nucleotide differences in the obg gene. Analytical specificity and sensitivity assessed using DNA from 194 M. synoviae field samples, three different batches of MS-H vaccine and from 43 samples representing four other avian Mycoplasma species proved to be 100%. The detection limit for field M. synoviae and MS-H vaccine strain was 10 2-3 and 10 2 colony-forming units PCR equivalents/g trachea mucus, respectively. The qPCR was able to detect both, field M. synoviae and MS-H vaccine strain in ratios of 1:100 determined both using spiked and field samples. One hundred and twenty samples from M. synoviae-infected non-vaccinated birds, 110 samples from M. synoviae-vaccinated birds from a bird experiment and 224 samples from M. synoviae negative (serology and PCR) birds were used to determine the relative sensitivity and specificity using a previously described M. synoviae PCR as reference. The relative sensitivity and specificity for field M. synoviae were 95.0% and 99.6%, respectively, and 94.6% and 100% for the MS-H-live vaccine, respectively. Field validation and confirmation by multi locus sequence typing revealed that the qPCR correctly distinguished between MS-H and field M. synoviae. Evaluation of the differentiating M. synoviae qPCR in three commercial flocks suggested transmission of MS-H-live vaccine from vaccinated to non-vaccinated flocks at the same farm. Furthermore, it showed evidence for the colonization with field M. synoviae in MS-H-vaccinated flocks.

  1. S1 gene sequence analysis of infectious bronchitis virus vaccinal strains (H120 & H52 and their embryo-passaged derivatives

    Directory of Open Access Journals (Sweden)

    Bakhshesh, M.

    2016-07-01

    Full Text Available Avian infectious bronchitis is an acute and highly contagious disease that mainly causes respiratory symptoms in poultry. A number of serotypes and variants of the viral agent with poor cross-protection are the major problem to achieve desired immunity from vaccination. The S1 subunit of S glycoprotein (spike is the major determinant of IBV so that a minor change in amino acid sequence of this protein, alters the virus strain. Therefore, characterization of the sequence of S1 gene is necessary to identify virus strains and their similarities with the vaccinal strains. In this research, the S1 sequence of H52 and H120 vaccinal strains of Razi Institute was fully characterized, and also the effect of serial passages in embryonated - eggs (5 passages beyond the master seed on the S1 gene was investigated. The results showed that H120 and H52 strains of Razi Institute are 100% identical to the reference vaccine strains available in the GenBank. In addition, the H52 strain showed one amino acid substitution from the 3rd passage in which Glycine (G was replaced by Valine (V at position 118 making these passages exactly identical to the H120 strain while no change occurred for the H120 strain during these passages. Analysis of the original vaccinal strains which are widely administered in Iran, is definitely useful for prevention and control strategies against the circulating viruses. To identify the genetic change(s responsible for attenuation of these strains during passages in embryonated-egg, characterization of other genes, especially those involved in replication is recommended.

  2. Improving influenza vaccine virus selection: report of a WHO informal consultation held at WHO headquarters, Geneva, Switzerland, 14-16 June 2010.

    Science.gov (United States)

    Ampofo, William K; Baylor, Norman; Cobey, Sarah; Cox, Nancy J; Daves, Sharon; Edwards, Steven; Ferguson, Neil; Grohmann, Gary; Hay, Alan; Katz, Jacqueline; Kullabutr, Kornnika; Lambert, Linda; Levandowski, Roland; Mishra, A C; Monto, Arnold; Siqueira, Marilda; Tashiro, Masato; Waddell, Anthony L; Wairagkar, Niteen; Wood, John; Zambon, Maria; Zhang, Wenqing

    2012-03-01

    • For almost 60 years, the WHO Global Influenza Surveillance and Response System (GISRS) has been the key player in monitoring the evolution and spread of influenza viruses and recommending the strains to be used in human influenza vaccines. The GISRS has also worked to continually monitor and assess the risk posed by potential pandemic viruses and to guide appropriate public health responses. • The expanded and enhanced role of the GISRS following the adoption of the International Health Regulations (2005), recognition of the continuing threat posed by avian H5N1 and the aftermath of the 2009 H1N1 pandemic provide an opportune time to critically review the process by which influenza vaccine viruses are selected. In addition to identifying potential areas for improvement, such a review will also help to promote greater appreciation by the wider influenza and policy-making community of the complexity of influenza vaccine virus selection. • The selection process is highly coordinated and involves continual year-round integration of virological data and epidemiological information by National Influenza Centres (NICs), thorough antigenic and genetic characterization of viruses by WHO Collaborating Centres (WHOCCs) as part of selecting suitable candidate vaccine viruses, and the preparation of suitable reassortants and corresponding reagents for vaccine standardization by WHO Essential Regulatory Laboratories (ERLs). • Ensuring the optimal effectiveness of vaccines has been assisted in recent years by advances in molecular diagnosis and the availability of more extensive genetic sequence data. However, there remain a number of challenging constraints including variations in the assays used, the possibility of complications resulting from non-antigenic changes, the limited availability of suitable vaccine viruses and the requirement for recommendations to be made up to a year in advance of the peak of influenza season because of production constraints.

  3. Antagonistic activity of selected strains of Bacillus thuringiensis ...

    African Journals Online (AJOL)

    121, were effective in the reduction of R. solani infection. In addition, GM-23 increased the length of pepper seedlings. These results suggest that the B. thuringiensis strains studied have an excellent potential to be used as bio-control agents of R.

  4. Genetic engineering of industrial Saccharomyces cerevisiae strains using a selection/counter-selection approach.

    Science.gov (United States)

    Kutyna, Dariusz R; Cordente, Antonio G; Varela, Cristian

    2014-01-01

    Gene modification of laboratory yeast strains is currently a very straightforward task thanks to the availability of the entire yeast genome sequence and the high frequency with which yeast can incorporate exogenous DNA into its genome. Unfortunately, laboratory strains do not perform well in industrial settings, indicating the need for strategies to modify industrial strains to enable strain development for industrial applications. Here we describe approaches we have used to genetically modify industrial strains used in winemaking.

  5. CpG oligodeoxynucleotides are a potent adjuvant for an inactivated polio vaccine produced from Sabin strains of poliovirus.

    Science.gov (United States)

    Yang, Chunting; Shi, Huiying; Zhou, Jun; Liang, Yanwen; Xu, Honglin

    2009-11-05

    Poliovirus transmission is controlled globally through world-wide use of a live attenuated oral polio vaccine (OPV). However, the imminence of global poliovirus eradication calls for a switch to the inactivated polio vaccine (IPV). Given the limited manufacturing capacity and high cost of IPV, this switch is unlikely in most developing and undeveloped countries. Adjuvantation is an effective strategy for antigen sparing. In this study, we evaluated the adjuvanticity of CpG oligodeoxynucleotides (CpG-ODN) for an experimental IPV produced from Sabin strains of poliovirus. Our results showed that CpG-ODN, alone or in combination with alum, can significantly enhance both the humoral and cellular immune responses to IPV in mice, and, consequently, the antigen dose could be reduced substantially. Therefore, our study suggests that the global use of IPV could be facilitated by using CpG-ODN or other feasible adjuvants.

  6. Evaluation of peptide selection approaches for epitope‐based vaccine design

    DEFF Research Database (Denmark)

    Schubert, B.; Lund, Ole; Nielsen, Morten

    2013-01-01

    A major challenge in epitope-based vaccine (EV) design stems from the vast genomic variation of pathogens and the diversity of the host cellular immune system. Several computational approaches have been published to assist the selection of potential T cell epitopes for EV design. So far, no thoro......A major challenge in epitope-based vaccine (EV) design stems from the vast genomic variation of pathogens and the diversity of the host cellular immune system. Several computational approaches have been published to assist the selection of potential T cell epitopes for EV design. So far...... in terms of in silico measurements simulating important vaccine properties like the ability of inducing protection against a multivariant pathogen in a population; the predicted immunogenicity; pathogen, allele, and population coverage; as well as the conservation of selected epitopes. Additionally, we...... evaluate the use of human leukocyte antigen (HLA) supertypes with regards to their applicability for population-spanning vaccine design. The results showed that in terms of induced protection methods that simultaneously aim to optimize pathogen and HLA coverage significantly outperform methods focusing...

  7. Selected anti-tumor vaccines merit a place in multimodal tumor therapies

    Energy Technology Data Exchange (ETDEWEB)

    Weiss, Eva-Maria; Wunderlich, Roland [Department of Radiation Oncology, University Hospital Erlangen, Friedrich-Alexander-Universität Erlangen-Nürnberg, Erlangen (Germany); Ebel, Nina [Department of Process Technology and Machinery, Friedrich-Alexander-Universität Erlangen-Nürnberg, Erlangen (Germany); Rubner, Yvonne [Department of Radiation Oncology, University Hospital Erlangen, Friedrich-Alexander-Universität Erlangen-Nürnberg, Erlangen (Germany); Schlücker, Eberhard [Department of Process Technology and Machinery, Friedrich-Alexander-Universität Erlangen-Nürnberg, Erlangen (Germany); Meyer-Pittroff, Roland [Competence Pool Weihenstephan, Technische Universität München, Freising (Germany); Ott, Oliver J.; Fietkau, Rainer; Gaipl, Udo S.; Frey, Benjamin, E-mail: benjamin.frey@uk-erlangen.de [Department of Radiation Oncology, University Hospital Erlangen, Friedrich-Alexander-Universität Erlangen-Nürnberg, Erlangen (Germany)

    2012-10-09

    Multimodal approaches are nowadays successfully applied in cancer therapy. Primary locally acting therapies such as radiotherapy (RT) and surgery are combined with systemic administration of chemotherapeutics. Nevertheless, the therapy of cancer is still a big challenge in medicine. The treatments often fail to induce long-lasting anti-tumor responses. Tumor recurrences and metastases result. Immunotherapies are therefore ideal adjuncts to standard tumor therapies since they aim to activate the patient's immune system against malignant cells even outside the primary treatment areas (abscopal effects). Especially cancer vaccines may have the potential both to train the immune system against cancer cells and to generate an immunological memory, resulting in long-lasting anti-tumor effects. However, despite promising results in phase I and II studies, most of the concepts finally failed. There are some critical aspects in development and application of cancer vaccines that may decide on their efficiency. The time point and frequency of medication, usage of an adequate immune adjuvant, the vaccine's immunogenic potential, and the tumor burden of the patient are crucial. Whole tumor cell vaccines have advantages compared to peptide-based ones since a variety of tumor antigens (TAs) are present. The master requirements of cell-based, therapeutic tumor vaccines are the complete inactivation of the tumor cells and the increase of their immunogenicity. Since the latter is highly connected with the cell death modality, the inactivation procedure of the tumor cell material may significantly influence the vaccine's efficiency. We therefore also introduce high hydrostatic pressure (HHP) as an innovative inactivation technology for tumor cell-based vaccines and outline that HHP efficiently inactivates tumor cells by enhancing their immunogenicity. Finally studies are presented proving that anti-tumor immune responses can be triggered by combining RT with selected

  8. EFFECTS OF STRAIN, CAGE DENSITY AND POSITION ON IMMUNE RESPONSE TO VACCINES AND BLOOD PARAMETERS IN LAYER PULLETS

    Directory of Open Access Journals (Sweden)

    Z. BOZKURT

    2009-05-01

    Full Text Available Two thousand 1-day-old layer chicks were used in the study from Lohman Brown, Isa Brown, Lohman White and Bowans White breeds. The chicks were placed in the at 3 cage densities (211.8, 274.5 and 370.6 cm2 per bird and on 3 positions (as top, middle and bottom tiers. All birds were kept under standard management policy and a commercial vaccination program was practiced. Total specific antibody titres to Infectious Brochitis Virus (IBV, Infectious Bursal Desease Virus (IBDV, Newcastle Disease Virus (NDV and Egg Drop Syndrome Virus (EDSV vaccines at the ages of 5, 10 and 20 weeks were serologically determined by ELISA. Cellmediated immune response was also evaluated. In commercial white egg laying strains specific antibody titres to IBV, IBDV, NDV and EDSV vaccines were greater than in Brown egg layer strains. Keeping in cage created more stress in Brown egg laying chicks than those in white egg laying chicks. As cage density increased, the ratio of heterophils to lymphocytes (H/L ratio slightly increased. Cage position had no influence on the titres of antibodies to IBV and IBDV vaccines but the position of cage in pullets where chicks were stocked, from top to bottom, NDV and EDSV antibody titre decreased and percentage of heterophils, H/L ratio and basophil rates were low. These findings suggest that cage-related stress could be decreased, resistance to diseases and finally well-being of hens may be improved if hens are kept under proper position and density within cage systems with respect to their physiological and behavioral characteristics that controlled by genes.

  9. Tularemia vaccine: Safety, reactogenicity, "Take" skin reactions, and antibody responses following vaccination with a new lot of the Francisella tularensis live vaccine strain - A phase 2 randomized clinical Trial.

    Science.gov (United States)

    Mulligan, Mark J; Stapleton, Jack T; Keitel, Wendy A; Frey, Sharon E; Chen, Wilbur H; Rouphael, Nadine; Edupuganti, Srilatha; Beck, Allison; Winokur, Patricia L; El Sahly, Hana M; Patel, Shital M; Atmar, Robert L; Graham, Irene; Anderson, Edwin; El-Kamary, Samer S; Pasetti, Marcela F; Sztein, Marcelo B; Hill, Heather; Goll, Johannes B

    2017-08-24

    Tularemia is caused by Francisella tularensis, a gram-negative bacterium that has been weaponized as an aerosol. For protection of personnel conducting biodefense research, the United States Army required clinical evaluation of a new lot of tularemia live vaccine strain manufactured in accordance with Current Good Manufacturing Practices. A phase 2 randomized clinical trial compared the new lot (DVC-LVS) to the existing vaccine that has been in use for decades (USAMRIID-LVS). The vaccines were delivered by scarification to 228 participants. Safety, reactogenicity, take and/or antibody levels were assessed on days 0, 1, 2, 8, 14, 28, 56, and 180. Both vaccines were safe and had acceptable reactogenicity profiles during six months of follow-up. There were no serious or grade 3 and 4 laboratory adverse events. Moderate systemic reactogenicity (mostly headache or feeling tired) was reported by ∼23% of participants receiving either vaccine. Injection site reactogenicity was mostly mild itchiness and pain. The frequencies of vaccine take skin reactions were 73% (95% CI, 64, 81) for DVC-LVS and 80% (95% CI, 71, 87) for USAMRIID-LVS. The 90% CI for the difference in proportions was -6.9% (-16.4, 2.6). The rates of seroconversion measured by microagglutination assay on days 28 or 56 were 94% (95% CI, 88, 98; n=98/104) for DVC-LVS and 94% (95% CI, 87, 97; n=103/110) for USAMRIID-LVS (p=1.00). Day 14 sera revealed more rapid seroconversion for DVC-LVS relative to USAMRIID-LVS: 82% (95% CI, 73, 89) versus 55% (95% CI, 45, 65), respectively (p<0.0001). The DVC-LVS vaccine had similar safety, reactogenicity, take and antibody responses compared to the older USAMRIID vaccine, and was superior for early (day 14) antibody production. Vaccination take was not a sensitive surrogate for seroconversion in a multi-center study where personnel at five research clinics performed assessments. ClinicalTrials.gov identifier NCT01150695. Copyright © 2017 The Authors. Published by Elsevier

  10. Virulent and Vaccine Strains of Streptococcus equi ssp. zooepidemicus Have Different Influences on Phagocytosis and Cytokine Secretion of Macrophages.

    Science.gov (United States)

    Jie, Peng; Zhe, Ma; Chengwei, Hua; Huixing, Lin; Hui, Zhang; Chengping, Lu; Hongjie, Fan

    2017-01-06

    Swine streptococcosis is a significant threat to the Chinese pig industry, and Streptococcus equi ssp. zooepidemicus (SEZ) is one of the major pathogens. SEZ ATCC35246 is a classical virulent strain, while SEZ ST171 is a Chinese attenuated vaccine strain. In this study, we employed stable isotope labeling by amino acids in cell culture and liquid chromatography-mass spectrometry (LC-MS) to determine the differential response of macrophages to infection by these two strains. Eighty-seven upregulated proteins and 135 downregulated proteins were identified. The proteomic results were verified by real-time polymerase chain reaction for 10 chosen genes and Western blotting for three proteins. All differentially abundant proteins were analyzed for their Gene Ontology and Kyoto Encyclopedia of Genes and Genomes annotations. Certain downregulated proteins were associated with immunity functions, and the upregulated proteins were related to cytomembrane and cytoskeleton regulation. The phagocytosis rate and cytokine genes transcription in Raw264.7 cells during SEZ ATCC35246 and ST171 infection were detected to confirm the bioinformatics results. These results showed that different effects on macrophage phagocytosis and cytokine expression might explain the different phenotypes of SEZ ATCC35246 and ST171 infection. This research provided clues to the mechanisms of host immunity responses to SEZ ST171and SEZ ATCC35246, which could identify potential therapy and vaccine development targets.

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

    Science.gov (United States)

    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. No demonstrable association between the Leningrad-Zagreb mumps vaccine strain and aseptic meningitis in a large clinical trial in Egypt.

    Science.gov (United States)

    Sharma, H J; Oun, S Aly; Bakr, S S Abou; Kapre, S V; Jadhav, S S; Dhere, R M; Bhardwaj, S

    2010-04-01

    To address the claim that the Leningrad-Zagreb (L-Z) mumps vaccine strain is causally associated with aseptic meningitis, a prospective, post-marketing safety study was conducted with a measles-mumps-rubella vaccine (MMR) (TRESIVAC(R); Serum Institute of India Ltd., Pune, India), which uses the L-Z strain as its mumps component in Egypt. In all, 453 119 children (65 423 children aged 16-24 months and 329 211 children aged 5-7 years) received MMR. The control groups which, as a result of local health regulations, were slightly younger than vaccinees, comprised 12 253 and 46 232 children, respectively. Using questionnaires, the parents recorded solicited local, systemic and neurological adverse events for up to 42 days post-vaccination. All data were analysed externally on an intention-to-treat basis by individuals not participating in the study. Local and/or systemic reactions were reported in a small percentage of participants, with pain, fever and parotitis being the most common signs among vaccinees in both age groups. No case of aseptic meningitis, encephalitis, anaphylaxis or convulsions was observed in any participant. Thus, in this series of more than 450 000 Egyptian children, the L-Z mumps vaccine strain in this vaccine did not cause aseptic meningitis. The vaccine is considerably cheaper than Western competitors and a valid alternative to other MMR vaccines.

  13. Immunological response to Brucella abortus strain 19 vaccination of cattle in a communal area in South Africa.

    Science.gov (United States)

    Simpson, Gregory J G; Marcotty, Tanguy; Rouille, Elodie; Chilundo, Abel; Letteson, Jean-Jacques; Godfroid, Jacques

    2018-03-29

    Brucellosis is of worldwide economic and public health importance. Heifer vaccination with live attenuated Brucella abortus strain 19 (S19) is the cornerstone of control in low- and middle-income countries. Antibody persistence induced by S19 is directly correlated with the number of colony-forming units (CFU) per dose. There are two vaccination methods: a 'high' dose (5-8 × 1010 CFU) subcutaneously injected or one or two 'low' doses (5 × 109 CFU) through the conjunctival route. This study aimed to evaluate serological reactions to the 'high' dose and possible implications of the serological findings on disease control. This study included 58 female cases, vaccinated at Day 0, and 29 male controls. Serum was drawn repeatedly and tested for Brucella antibodies using the Rose Bengal Test (RBT) and an indirect enzyme-linked immunosorbent assay (iELISA). The cases showed a rapid antibody response with peak RBT positivity (98%) at 2 weeks and iELISA (95%) at 8 weeks, then decreased in an inverse logistic curve to 14% RBT and 32% iELISA positive at 59 weeks and at 4.5 years 57% (4/7 cases) demonstrated a persistent immune response (RBT, iELISA or Brucellin skin test) to Brucella spp. Our study is the first of its kind documenting the persistence of antibodies in an African communal farming setting for over a year to years after 'high' dose S19 vaccination, which can be difficult to differentiate from a response to infection with wild-type B. abortus. A recommendation could be using a 'low' dose or different route of vaccination.

  14. Morphology of immune organs after very virulent plus strain of Marek's disease virus infection in vaccinated hens.

    Science.gov (United States)

    Madej, J P; Woźniakowski, G; Gaweł, A

    2016-01-01

    Marek's disease (MD) outbreaks in poultry flocks may be associated with overriding of vaccine immune protection by very virulent (vvMDV) or very virulent plus (vv+MDV) strains. This paper presents the study on lymphoid organ morphology in the latent phase of MD caused by vv+MDV which break post-vaccinal protection in hens. We also immunohistochemically examined B and T populations as well as B/T and CD4+/CD8+ ratio of lymphocytes in lymphatic organs and, as a background, in MD lymphomas from non-lymphatic organs. The number of antigen expressed cells was evaluated as a percentage of positive cells in the one power field. Organ samples were collected from 24 dead reproductive hens (Ross 308 line) in age between 35-56 weeks, infected with vv+MDV. The hens originated from farms with MD outbreaks, despite earlier routine vaccination with CVI988/Rispens + HVT. The control organ samples originated from 15 clinically healthy hens at the same age and line, subjected to the same vaccination schedule. The number of CD3+, CD8+ and TCRγδ+ cells was significantly lower in MDV infected thymus, spleen and cecal tonsils in comparison to that found in the control organs. The proportion of CD4+ was also distinctly reduced in the thymus and limited in the spleen of MDV infected hens. This study revealed that infection with field vv+MDV isolates might break post-vaccinal protection and influence the central and peripheral immune system. The decrease in CD8+ and TCRγδ+ cell number in the thymus, spleen and cecal tonsils suggests that primarily these cells are involved in cell-mediated cytotoxicity against MDV transformed cells during latency.

  15. Design and Validation of a Cyclic Strain Bioreactor to Condition Spatially-Selective Scaffolds in Dual Strain Regimes

    Directory of Open Access Journals (Sweden)

    J. Matthew Goodhart

    2014-03-01

    Full Text Available The objective of this study was to design and validate a unique bioreactor design for applying spatially selective, linear, cyclic strain to degradable and non-degradable polymeric fabric scaffolds. This system uses a novel three-clamp design to apply cyclic strain via a computer controlled linear actuator to a specified zone of a scaffold while isolating the remainder of the scaffold from strain. Image analysis of polyethylene terephthalate (PET woven scaffolds subjected to a 3% mechanical stretch demonstrated that the stretched portion of the scaffold experienced 2.97% ± 0.13% strain (mean ± standard deviation while the unstretched portion experienced 0.02% ± 0.18% strain. NIH-3T3 fibroblast cells were cultured on the PET scaffolds and half of each scaffold was stretched 5% at 0.5 Hz for one hour per day for 14 days in the bioreactor. Cells were checked for viability and proliferation at the end of the 14 day period and levels of glycosaminoglycan (GAG and collagen (hydroxyproline were measured as indicators of extracellular matrix production. Scaffolds in the bioreactor showed a seven-fold increase in cell number over scaffolds cultured statically in tissue culture plastic petri dishes (control. Bioreactor scaffolds showed a lower concentration of GAG deposition per cell as compared to the control scaffolds largely due to the great increase in cell number. A 75% increase in hydroxyproline concentration per cell was seen in the bioreactor stretched scaffolds as compared to the control scaffolds. Surprisingly, little differences were experienced between the stretched and unstretched portions of the scaffolds for this study. This was largely attributed to the conditioned and shared media effect. Results indicate that the bioreactor system is capable of applying spatially-selective, linear, cyclic strain to cells growing on polymeric fabric scaffolds and evaluating the cellular and matrix responses to the applied strains.

  16. Uptake and impact of vaccinating school age children against influenza during a season with circulation of drifted influenza A and B strains, England, 2014/15.

    Science.gov (United States)

    Pebody, Richard G; Green, Helen K; Andrews, Nick; Boddington, Nicola L; Zhao, Hongxin; Yonova, Ivelina; Ellis, Joanna; Steinberger, Sophia; Donati, Matthew; Elliot, Alex J; Hughes, Helen E; Pathirannehelage, Sameera; Mullett, David; Smith, Gillian E; de Lusignan, Simon; Zambon, Maria

    2015-01-01

    The 2014/15 influenza season was the second season of roll-out of a live attenuated influenza vaccine (LAIV) programme for healthy children in England. During this season, besides offering LAIV to all two to four year olds, several areas piloted vaccination of primary (4-11 years) and secondary (11-13 years) age children. Influenza A(H3N2) circulated, with strains genetically and antigenically distinct from the 2014/15 A(H3N2) vaccine strain, followed by a drifted B strain. We assessed the overall and indirect impact of vaccinating school age children, comparing cumulative disease incidence in targeted and non-targeted age groups in vaccine pilot to non-pilot areas. Uptake levels were 56.8% and 49.8% in primary and secondary school pilot areas respectively. In primary school age pilot areas, cumulative primary care influenza-like consultation, emergency department respiratory attendance, respiratory swab positivity, hospitalisation and excess respiratory mortality were consistently lower in targeted and non-targeted age groups, though less for adults and more severe end-points, compared with non-pilot areas. There was no significant reduction for excess all-cause mortality. Little impact was seen in secondary school age pilot only areas compared with non-pilot areas. Vaccination of healthy primary school age children resulted in population-level impact despite circulation of drifted A and B influenza strains.

  17. Immunogenicity, reactogenicity, and safety of a P1.7b,4 strain-specific serogroup B meningococcal vaccine given to preteens.

    Science.gov (United States)

    Hosking, Jamie; Rasanathan, Kumanan; Mow, Florina Chan; Jackson, Catherine; Martin, Diana; O'Hallahan, Jane; Oster, Philipp; Ypma, Ellen; Reid, Stewart; Aaberge, Ingeborg; Crengle, Sue; Stewart, Joanna; Lennon, Diana

    2007-11-01

    New Zealand (NZ) has experienced a Neisseria meningitidis serogroup B epidemic since 1991. MeNZB, a strain-specific outer membrane vesicle vaccine made using an NZ epidemic strain isolate, NZ98/254 (B:4:P1.7b,4), from two manufacturing sites, the Norwegian Institute of Public Health (NIPH) and Chiron Vaccines (CV; now Novartis), was evaluated for safety, immunogenicity, and reactogenicity in this observer-blind trial with 8- to 12-year-old children. In year 1, cohort A (n = 302) was randomized 4:1 for receipt of NIPH-MeNZB or MenBvac (Norwegian parent vaccine strain 44/76; B:15:P1.7,16). In year 2, cohort B (n = 313) was randomized 4:1 for receipt of CV-MeNZB or NIPH-MeNZB. Participants all received three vaccinations 6 weeks apart. Local and systemic reactions were monitored for 7 days. Seroresponse was defined as a fourfold or greater rise in the serum bactericidal antibody titer from the baseline titer as measured by a serum bactericidal assay. Those with baseline titers of /=1:8 to serorespond. Intention-to-treat (ITT) and per protocol (PP) analyses are presented. In cohort A, 74% (ITT) and 73% (PP) of NIPH-MeNZB recipients demonstrated seroresponses against NZ98/254 after three doses, versus 32% (ITT and PP) of MenBvac recipients. In cohort B, seroresponses against NZ98/254 after three doses occurred in 79% (ITT and PP) of CV-MeNZB versus 75% (ITT) and 76% (PP) of NIPH-MeNZB recipients. Vaccines were tolerable, with no vaccine-related serious adverse events. In conclusion, the NZ strain meningococcal B vaccine (MeNZB) from either manufacturing site was immunogenic against New Zealand epidemic vaccine strain meningococci with no safety concerns when given in three doses to these 8- to 12-year-old children.

  18. Cross-Protection against Marburg Virus Strains by Using a Live, Attenuated Recombinant Vaccine

    National Research Council Canada - National Science Library

    Daddario-DiCaprio, Kathleen M; Geisbert, Thomas W; Geisbert, Joan B; Stroeher, Ute; Hensley, Lisa E; Grolla, Allen; Fritz, Elizabeth A; Feldmann, Friederike; Feldmann, Heinz; Jones, Steven M

    2006-01-01

    .... MARV is also considered to have potential as a biological weapon. Recently, we reported the development of a promising attenuated, replication-competent vaccine against MARV based on recombinant vesicular stomatitis virus (VSV...

  19. The influence of the growth conditions of the plague microbe vaccine strain colonies on the fractal dimension of biospeckles

    International Nuclear Information System (INIS)

    Ul'yanov, A S; Lyapina, A M; Ulianova, O V; Fedorova, V A; Uianov, S S

    2011-01-01

    Specific statistical characteristics of biospeckles, emerging under the diffraction of coherent beams on the bacterial colonies, are studied. The dependence of the fractal dimensions of biospeckles on the conditions of both illumination and growth of the colonies is studied theoretically and experimentally. Particular attention is paid to the fractal properties of biospeckles, emerging under the scattering of light by the colonies of the vaccinal strain of the plague microbe. The possibility in principle to classify the colonies of Yersinia pestis EV NIIEG using the fractal dimension analysis is demonstrated. (optical technologies in biophysics and medicine)

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

    Science.gov (United States)

    Pridgeon, Julia W; Klesius, Phillip H

    2013-05-31

    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-resistant S. agalactiae isolates were tested in 10-12g Nile tilapia by intraperitoneal injection at dose of 2×10(7)CFU/fish, 31 were found to be avirulent to fish. Of the 31 avirulent sparfloxacin-resistant S. agalactiae isolates, 30 provided 75-100% protection to 10-12g Nile tilapia against challenges with a virulent S. agalactiae isolate Sag 50. When the virulence of the 30 sparfloxacin-resistant S. agalactiae isolates was tested in 3-5g Nile tilapia by intraperitoneal injection at dose of 2×10(7)CFU/fish, six were found to be avirulent to 3-5g Nile tilapia. Of the six avirulent sparfloxacin-resistant S. agalactiae isolates, four provided 3-5g Nile tilapia 100% protection against challenges with homologous isolates, including Sag 97-spar isolate that was non-hemolytic. However, Sag 97-spar failed to provide broad cross-protection against challenges with heterologous isolates. When Nile tilapia was vaccinated with a polyvalent vaccine consisting of 30 sparfloxacin-resistant S. agalactiae isolates at dose of 2×10(6)CFU/fish, the polyvalent vaccine provided significant (PS. agalactiae. Taken together, our results suggest that a polyvalent vaccine consisting of various strains of S. agalactiae might be essential to provide broader protection to Nile tilapia against infections caused by S. agalactiae. Published by Elsevier Ltd.

  1. Oral immunisation of laying hens with the live vaccine strains of TAD Salmonella vac E and TAD Salmonella vac T reduces internal egg contamination with Salmonella Enteritidis.

    Science.gov (United States)

    Gantois, Inne; Ducatelle, Richard; Timbermont, Leen; Boyen, Filip; Bohez, Lotte; Haesebrouck, Freddy; Pasmans, Frank; van Immerseel, Filip

    2006-09-11

    Eggs are a major source of human infections with Salmonella. Therefore controlling egg contamination in laying hen flocks is one of the main targets for control programmes. A study was carried out to assess the effect of oral vaccination with TAD Salmonella vac E, TAD Salmonella vac T and with both vaccines TAD Salmonella vac E and TAD Salmonella vac T, on colonization of the reproductive tract and internal egg contamination of laying hens with Salmonella Enteritidis. Three groups of 30 laying hens were vaccinated at 1 day, 6 weeks and 16 weeks of age with either one of the vaccine strains, or a combination of both vaccine strains, while a fourth group was left unvaccinated. At 24 weeks of age, the birds were intravenously challenged with 0.5 ml containing 5 x 10(7)cfu Salmonella Enteritidis PT4 S1400/94. The number of oviducts from which Salmonella was isolated, was significantly lower in the vaccinated than in the non-vaccinated hens at 3 weeks post-challenge. Significantly less egg contents were Salmonella positive in the birds vaccinated with TAD Salmonella vac E or TAD Salmonella vac T (12/105 batches of eggs in both groups) than in the unvaccinated birds (28/105 batches of eggs). Internal egg contamination in the hens vaccinated with both TAD Salmonella vac E and TAD Salmonella vac T was even more reduced, as over the whole experiment, only one batch of eggs was positive. In conclusion, these data indicate that vaccination of laying hens with these live vaccines could be considered as a valuable tool in controlling internal egg contamination.

  2. Immunogenicity and safety of a novel MMR vaccine (live, freeze-dried) containing the Edmonston-Zagreb measles strain, the Hoshino mumps strain, and the RA 27/3 rubella strain: Results of a randomized, comparative, active controlled phase III clinical trial.

    Science.gov (United States)

    Sood, Ashwani; Mitra, Monjori; Joshi, Himanshu Arvind; Nayak, Uma Siddhartha; Siddaiah, Prashanth; Babu, T Ramesh; Mahapatro, Samarendra; Sanmukhani, Jayesh; Gupta, Gaurav; Mittal, Ravindra; Glueck, Reinhard

    2017-07-03

    This phase III clinical trial was conducted to evaluate the immunogenicity and safety of the single-dose and multi-dose formulations of a novel MMR vaccine (live, freeze-dried) developed by M/s Cadila Healthcare Limited, India (Cadila MMR vaccine), containing the Hoshino mumps strain, compared to that of an existing MMR vaccine (live, freeze-dried) developed by M/s Serum Institute of India Limited, India (Serum MMR vaccine). These two vaccines have similar measles and rubella strains, but different mumps strains (Hoshino in Cadila MMR vaccine, and L-Zagreb in Serum MMR vaccine). Three hundred and twenty-eight subjects of either sex, aged 15-18 months, were randomized in a 2:1 ratio to receive either the Cadila or Serum MMR vaccine. Immunogenicity assessments (IgG antibodies against measles, mumps, and rubella viruses) were done at baseline and 42 d after vaccination. Solicited (local and systemic) and unsolicited adverse events were recorded for up to 42 d following vaccination. The Cadila MMR vaccine was found to be non-inferior to the Serum MMR vaccine in terms of end-of-study proportion of subjects seropositive for anti-measles antibodies (100.0% in both groups), anti-mumps antibodies (94.5% vs. 94.0%), and anti-rubella antibodies (95.5% vs. 91.0%). Both vaccines were well tolerated by all study participants; the most common adverse event reported in both groups was fever, followed by rash. The results of this phase III clinical trial show that the novel Cadila MMR vaccine is non-inferior to the Serum MMR vaccine.

  3. Selection of inoculum size and Saccharomyces cerevisiae strain for ...

    African Journals Online (AJOL)

    SAM

    2014-07-02

    Jul 2, 2014 ... The aim of this work was to select an inoculum concentration and a ... (UFPEDA 1238 and UFPEDA 1334) were used to ferment a culture medium containing .... quantified by HPLC (Agilent HP 1100, Germany) in an Aminex.

  4. Preparation for emergence of an Eastern European porcine reproductive and respiratory syndrome virus (PRRSV) strain in Western Europe: Immunization with modified live virus vaccines or a field strain confers partial protection.

    Science.gov (United States)

    Renson, P; Fablet, C; Le Dimna, M; Mahé, S; Touzain, F; Blanchard, Y; Paboeuf, F; Rose, N; Bourry, O

    2017-05-01

    The porcine reproductive and respiratory syndrome virus (PRRSV) causes huge economic losses for the swine industry worldwide. In the past several years, highly pathogenic strains that lead to even greater losses have emerged. For the Western European swine industry, one threat is the possible introduction of Eastern European PRRSV strains (example Lena genotype 1.3) which were shown to be more virulent than common Western resident strains under experimental conditions. To prepare for the possible emergence of this strain in Western Europe, we immunized piglets with a Western European PRRSV field strain (Finistere: Fini, genotype 1.1), a new genotype 1 commercial modified live virus (MLV) vaccine (MLV1) or a genotype 2 commercial MLV vaccine (MLV2) to evaluate and compare the level of protection that these strains conferred upon challenge with the Lena strain 4 weeks later. Results show that immunization with Fini, MLV1 or MLV2 strains shortened the Lena-induced hyperthermia. In the Fini group, a positive effect was also demonstrated in growth performance. The level of Lena viremia was reduced for all immunized groups (significantly so for Fini and MLV2). This reduction in Lena viremia was correlated with the level of Lena-specific IFNγ-secreting cells. In conclusion, we showed that a commercial MLV vaccine of genotype 1 or 2, as well as a field strain of genotype 1.1 may provide partial clinical and virological protection upon challenge with the Lena strain. The cross-protection induced by these immunizing strains was not related with the level of genetic similarity to the Lena strain. The slightly higher level of protection established with the field strain is attributed to a better cell-mediated immune response. Copyright © 2017 Elsevier B.V. All rights reserved.

  5. Did Large-Scale Vaccination Drive Changes in the Circulating Rotavirus Population in Belgium?

    Science.gov (United States)

    Pitzer, Virginia E.; Bilcke, Joke; Heylen, Elisabeth; Crawford, Forrest W.; Callens, Michael; De Smet, Frank; Van Ranst, Marc; Zeller, Mark; Matthijnssens, Jelle

    2015-01-01

    Vaccination can place selective pressures on viral populations, leading to changes in the distribution of strains as viruses evolve to escape immunity from the vaccine. Vaccine-driven strain replacement is a major concern after nationwide rotavirus vaccine introductions. However, the distribution of the predominant rotavirus genotypes varies from year to year in the absence of vaccination, making it difficult to determine what changes can be attributed to the vaccines. To gain insight in the underlying dynamics driving changes in the rotavirus population, we fitted a hierarchy of mathematical models to national and local genotype-specific hospitalization data from Belgium, where large-scale vaccination was introduced in 2006. We estimated that natural- and vaccine-derived immunity was strongest against completely homotypic strains and weakest against fully heterotypic strains, with an intermediate immunity amongst partially heterotypic strains. The predominance of G2P[4] infections in Belgium after vaccine introduction can be explained by a combination of natural genotype fluctuations and weaker natural and vaccine-induced immunity against infection with strains heterotypic to the vaccine, in the absence of significant variation in strain-specific vaccine effectiveness against disease. However, the incidence of rotavirus gastroenteritis is predicted to remain low despite vaccine-driven changes in the distribution of genotypes. PMID:26687288

  6. Identification of a new genetic marker in Mycoplasma synoviae vaccine strain MS-H and development of a strategy using polymerase chain reaction and high-resolution melting curve analysis for differentiating MS-H from field strains.

    Science.gov (United States)

    Zhu, Ling; Konsak, Barbara M; Olaogun, Olusola M; Agnew-Crumptona, Rebecca; Kanci, Anna; Marenda, Marc S; Browning, Glenn F; Noormohammadi, Amir H

    2017-10-01

    Mycoplasma synoviae (MS) is an economically important avian pathogen worldwide, causing subclinical respiratory tract infection and infectious synovitis in chickens and turkeys. A temperature-sensitive (ts + ) live attenuated vaccine MS-H, derived from the Australian field strain 86079/7NS, is now widely used in many countries to control the disease induced by MS. Differentiation of MS-H vaccine from field strains is crucial for monitoring vaccination programs in commercial poultry. Comparison of genomic sequences of MS-H and its parent strain revealed an adenine deletion at nucleotide position 468 of the MS-H oppF-1 gene. This mutation was shown to be unique to MS-H in further comparative analyses of oppF-1 genes of MS-H re-isolates and field strains from Australia and other countries. Based on this single nucleotide, a combination of nested PCR and high-resolution melting (HRM) curve analysis was used to evaluate its potential for use in differentiation of MS-H from field strains. The mean genotype confidence percentages of 99.27 and 48.20 for MS-H and field strains, respectively, demonstrated the high discriminative power of the newly developed assay (oppF PCR-HRM). A set of 13 tracheal swab samples collected from MS-H vaccinated specific pathogen free birds and commercial chicken flocks infected with MS were tested using the oppF PCR-HRM test and results were totally consistent with those obtained using vlhA genotyping. The nested-PCR HRM method established in this study proved to be a rapid, simple and cost effective tool for discriminating the MS-H vaccine strain from Australian and international strains in pure cultures and on tracheal swabs. Copyright © 2017 Elsevier B.V. All rights reserved.

  7. Identification of mutations in the M RNA of a candidate vaccine strain of Rift Valley fever virus.

    Science.gov (United States)

    Takehara, K; Min, M K; Battles, J K; Sugiyama, K; Emery, V C; Dalrymple, J M; Bishop, D H

    1989-04-01

    The M RNA species of a candidate vaccine strain of Rift Valley fever virus (RVFV ZH-548M12), derived by consecutive high level mutagenesis using 5-fluorouracil (H. Caplen, C. J. Peters, and D. H. L. Bishop, J. Gen. Virol., 66, 2271-2277, 1985), has been cloned and the cDNA sequenced. The data have been compared to those obtained for the parent virus strain RVFV ZH-548 as well as the previously published data for RVFV ZH-501 (M. S. Collett, A. F. Purchio, K. Keegan, S. Frazier, W. Hays, D. K. Anderson, M. D. Parker, C. Schmaljohn, J. Schmidt, and J. M. Dalrymple, Virology, 144, 228-245, 1985). Some eight nucleotide and three amino acid differences were identified between the M RNAs of ZH-501 and ZH-548. Between the M RNAs of ZH-548 and that of the M12 mutant there were 12 nucleotide and 7 amino acid changes. Unique to the mutant virus is a new AUG codon upstream of that which initiates the open reading frame of the RVFV M gene product (the viral glycoprotein precursor). The significance of this and other differences in the mutant RNA with regard to the derivation and potential attenuation of the candidate vaccine is discussed.

  8. Genomic analysis of an attenuated Chlamydia abortus live vaccine strain reveals defects in central metabolism and surface proteins.

    Science.gov (United States)

    Burall, L S; Rodolakis, A; Rekiki, A; Myers, G S A; Bavoil, P M

    2009-09-01

    Comparative genomic analysis of a wild-type strain of the ovine pathogen Chlamydia abortus and its nitrosoguanidine-induced, temperature-sensitive, virulence-attenuated live vaccine derivative identified 22 single nucleotide polymorphisms unique to the mutant, including nine nonsynonymous mutations, one leading to a truncation of pmpG, which encodes a polymorphic membrane protein, and two intergenic mutations potentially affecting promoter sequences. Other nonsynonymous mutations mapped to a pmpG pseudogene and to predicted coding sequences encoding a putative lipoprotein, a sigma-54-dependent response regulator, a PhoH-like protein, a putative export protein, two tRNA synthetases, and a putative serine hydroxymethyltransferase. One of the intergenic mutations putatively affects transcription of two divergent genes encoding pyruvate kinase and a putative SOS response nuclease, respectively. These observations suggest that the temperature-sensitive phenotype and associated virulence attenuation of the vaccine strain result from disrupted metabolic activity due to altered pyruvate kinase expression and/or alteration in the function of one or more membrane proteins, most notably PmpG and a putative lipoprotein.

  9. Antigenic and genetic comparison of foot-and-mouth disease virus serotype O Indian vaccine strain, O/IND/R2/75 against currently circulating viruses.

    Science.gov (United States)

    Mahapatra, Mana; Yuvaraj, S; Madhanmohan, M; Subramaniam, S; Pattnaik, B; Paton, D J; Srinivasan, V A; Parida, Satya

    2015-01-29

    Foot-and-mouth disease (FMD) virus serotype O is the most common cause of FMD outbreaks in India and three of the six lineages that have been described are most frequently detected, namely Ind2001, PanAsia and PanAsia 2. We report the full capsid sequence of 21 serotype O viruses isolated from India between 2002 and 2012. All these viruses belong to the Middle East-South Asia (ME-SA) topotype. The serological cross-reactivity of a bovine post-vaccination serum pool raised against the current Indian vaccine strain, O/IND/R2/75,was tested by virus neutralisation test with the 23 Indian field isolates, revealing a good match between the vaccine and the field isolates. The cross reactivity of the O/IND/R2/75 vaccine with 19 field isolates from other countries (mainly from Asia and Africa) revealed a good match to 79% of the viruses indicating that the vaccine strain is broadly cross-reactive and could be used to control FMD in other countries. Comparison of the capsid sequences of the serologically non-matching isolates with the vaccine strain sequence identified substitutions in neutralising antigenic sites 1 and 2, which could explain the observed serological differences. Copyright © 2014 The Authors. Published by Elsevier Ltd.. All rights reserved.

  10. Selection of autochthonous Oenococcus oeni strains according to their oenological properties and vinification results.

    Science.gov (United States)

    Ruiz, Patricia; Izquierdo, Pedro Miguel; Seseña, Susana; Palop, María Llanos

    2010-02-28

    The goal of this study is to carry out a characterization of 84 Oenococcus oeni strains isolated from Tempranillo wine samples taken at the cellars in Castilla-La Mancha, in order to select those showing the highest potential as oenological starter cultures. Various oenological properties were analyzed and the ability of some of these strains to grow and undergo MLF in simulated laboratory microvinifications was tested. Twenty-two strains were selected on the basis of fermentation assays and the eight that produced the best results in the chemical analysis of the wines were chosen for further assays. None of the eight strains was either able to produce biogenic amines or displayed tannase or anthocyanase activities. On the other hand all presented activity against p-NP-beta Glucopyranoside, p-NP-alpha Glucopyranoside and p-NP-beta xylopyranoside. Randomly Amplified Polymorphic DNA (RAPD)-PCR was used to determine the colonizing ability of the inoculated strains. C22L9 and D13L13 strains showed the highest implantation values. On the basis of this characterization, two strains have been selected which are suitable as starter cultures for MLF of Tempranillo wine. Use of these strains will ensure that MLF proceeds successfully and gives retention of the organoleptic characteristics of wines made in Castilla-La Mancha. (c) 2009 Elsevier B.V. All rights reserved.

  11. Development of a multiplex amplification refractory mutation system reverse transcription polymerase chain reaction assay for the differential diagnosis of Feline leukemia virus vaccine and wild strains.

    Science.gov (United States)

    Ho, Chia-Fang; Chan, Kun-Wei; Yang, Wei-Cheng; Chiang, Yu-Chung; Chung, Yang-Tsung; Kuo, James; Wang, Chi-Young

    2014-07-01

    A multiplex amplification refractory mutation system reverse transcription polymerase chain reaction (ARMS RT-PCR) was developed for the differential diagnosis of Feline leukemia virus (FeLV) vaccine and wild-type strains based on a point mutation between the vaccine strain (S) and the wild-type strain (T) located in the p27 gene. This system was further upgraded to obtain a real-time ARMS RT-PCR (ARMS qRT-PCR) with a high-resolution melt analysis (HRMA) platform. The genotyping of various strains of FeLV was determined by comparing the HRMA curves with the defined wild-type FeLV (strain TW1), and the results were expressed as a percentage confidence. The detection limits of ARMS RT-PCR and ARMS qRT-PCR combined with HRMA were 100 and 1 copies of transcribed FeLV RNA per 0.5 ml of sample, respectively. No false-positive results were obtained with 6 unrelated pathogens and 1 feline cell line. Twelve FeLV Taiwan strains were correctly identified using ARMS qRT-PCR combined with HRMA. The genotypes of the strains matched the defined FeLV wild-type strain genotype with at least 91.17% confidence. A higher degree of sequence polymorphism was found throughout the p27 gene compared with the long terminal repeat region. In conclusion, the current study describes the phylogenetic relationship of the FeLV Taiwan strains and demonstrates that the developed ARMS RT-PCR assay is able to be used to detect the replication of a vaccine strain that has not been properly inactivated, thus acting as a safety check for the quality of FeLV vaccines.

  12. Antagonistic Activity of Lactobacillus reuteri Strains on the Adhesion Characteristics of Selected Pathogens.

    Science.gov (United States)

    Singh, Tejinder P; Kaur, Gurpreet; Kapila, Suman; Malik, Ravinder K

    2017-01-01

    Adhesion ability of probiotics is the key factor that decides their colonization in the gastrointestinal tract and potential to inhibit pathogens. Therefore, adhesion ability can be considered as a key determinant for probiotic efficacy. Presents study documents the antagonistic activity of viable/untreated, Lithium chloride (LiCl) treated or heat-killed forms of eight probiotic Lactobacillus reuteri strains on the adhesion characteristics of selected pathogens. All strains investigated were able to adhere to Caco-2 cells. L. reuteri strains tested were able to inhibit and displace ( P strain L. reuteri LR6 showed the strongest adhesion and pathogen inhibition ability among the eight L. reuteri strains tested. In addition, the abilities to inhibit and to displace adhered pathogens depended on both the probiotic and the pathogen strains tested suggesting the involvement of various mechanisms. The adhesion and antagonistic potential of the probiotic strains were significantly decreased upon exposure to 5 M LiCl, showing that surface molecules, proteinaceous in nature, are involved. The heat-killed forms of the probiotic L. reuteri strains also inhibited the attachment of selected pathogens to Caco-2 cells. In conclusion, in vitro assays showed that L. reuteri strains, as viable or heat-killed forms, are adherent to Caco-2 cells and are highly antagonistic to pathogens tested in which surface associated proteins play an important role.

  13. Host range, growth property, and virulence of the smallpox vaccine: Vaccinia virus Tian Tan strain

    International Nuclear Information System (INIS)

    Fang Qing; Yang Lin; Zhu Weijun; Liu Li; Wang Haibo; Yu Wenbo; Xiao Genfu; Tien Po; Zhang Linqi; Chen Zhiwei

    2005-01-01

    Vaccinia Tian Tan (VTT) was used as a vaccine against smallpox in China for millions of people before 1980, yet the biological characteristics of the virus remain unclear. We have characterized VTT with respect to its host cell range, growth properties in vitro, and virulence in vivo. We found that 11 of the 12 mammalian cell lines studied are permissive to VTT infection whereas one, CHO-K1, is non-permissive. Using electron microscopy and sequence analysis, we found that the restriction of VTT replication in CHO-K1 is at a step before viral maturation probably due to the loss of the V025 gene. Moreover, VTT is significantly less virulent than vaccinia WR but remains neurovirulent in mice and causes significant body weight loss after intranasal inoculation. Our data demonstrate the need for further attenuation of VTT to serve either as a safer smallpox vaccine or as a live vaccine vector for other pathogens

  14. Vaccine and Wild-Type Strains of Yellow Fever Virus Engage Distinct Entry Mechanisms and Differentially Stimulate Antiviral Immune Responses

    Directory of Open Access Journals (Sweden)

    Maria Dolores Fernandez-Garcia

    2016-02-01

    Full Text Available The live attenuated yellow fever virus (YFV vaccine 17D stands as a “gold standard” for a successful vaccine. 17D was developed empirically by passaging the wild-type Asibi strain in mouse and chicken embryo tissues. Despite its immense success, the molecular determinants for virulence attenuation and immunogenicity of the 17D vaccine are poorly understood. 17D evolved several mutations in its genome, most of which lie within the envelope (E protein. Given the major role played by the YFV E protein during virus entry, it has been hypothesized that the residues that diverge between the Asibi and 17D E proteins may be key determinants of attenuation. In this study, we define the process of YFV entry into target cells and investigate its implication in the activation of the antiviral cytokine response. We found that Asibi infects host cells exclusively via the classical clathrin-mediated endocytosis, while 17D exploits a clathrin-independent pathway for infectious entry. We demonstrate that the mutations in the 17D E protein acquired during the attenuation process are sufficient to explain the differential entry of Asibi versus 17D. Interestingly, we show that 17D binds to and infects host cells more efficiently than Asibi, which culminates in increased delivery of viral RNA into the cytosol and robust activation of the cytokine-mediated antiviral response. Overall, our study reveals that 17D vaccine and Asibi enter target cells through distinct mechanisms and highlights a link between 17D attenuation, virus entry, and immune activation.

  15. Pseudomonas fluorescens strains selectively suppress annual bluegrass (Poa annua L.)

    Science.gov (United States)

    Annual bluegrass (Poa annua L.) is a cool-season annual grass that is a major weed species in turf, turfgrass-seed production, sod production, and golf courses of the western United States. There are few selective herbicides available for the management of annual bluegrass. While the life cycles o...

  16. Identification of the 1B vaccine strain of Chlamydia abortus in aborted placentas during the investigation of toxaemic and systemic disease in sheep.

    Science.gov (United States)

    Sargison, N D; Truyers, I G R; Howie, F E; Thomson, J R; Cox, A L; Livingstone, M; Longbottom, D

    2015-09-01

    One hundred and forty Cheviot and 100 Suffolk cross Mule primiparous 1-2-year-old ewes, from a flock of about 700 ewes, were vaccinated with an attenuated live 1B strain Chlamydia abortus vaccine about 4 weeks before ram introduction (September 2011). Between 08 March and 01 April 2012, 50 2-year-old ewes aborted and 29 of these died, despite antimicrobial and anti-inflammatory treatment and supportive care. Seven fetuses and three placentae from five 2-year-old ewes were submitted for pathological investigation. The aborted fetuses showed stages of autolysis ranging from being moderately fresh to putrefaction. Unusual, large multifocal regions of thickened membranes, with a dull red granular surface and moderate amounts of grey-white surface exudate were seen on each of the placentae. Intracellular, magenta-staining, acid fast inclusions were identified in Ziehl Neelsen-stained placental smears. Immunohistochemistry for Chlamydia-specific lipopolysaccharide showed extensive positive labelling of the placental epithelia. Molecular analyses of the aborted placentae demonstrated the presence of the 1B vaccine-type strain of C. abortus and absence of any wild-type field strain. The vaccine strain bacterial load of the placental tissue samples was consistent with there being an association between vaccination and abortion. Initial laboratory investigations resulted in a diagnosis of chlamydial abortion. Further investigations led to the identification of the 1B vaccine strain of C. abortus in material from all three of the submitted aborted placentae. Timely knowledge and understanding of any potential problems caused by vaccination against C. abortus are prerequisites for sustainable control of chlamydial abortion. This report describes the investigation of an atypical abortion storm in sheep, and describes the identification of the 1B vaccine strain of C. abortus in products of abortion. The significance of this novel putative association between the vaccine strain

  17. Genomic expression catalogue of a global collection of BCG vaccine strains show evidence for highly diverged metabolic and cell-wall adaptations

    KAUST Repository

    Abdallah, Abdallah

    2015-10-21

    Although Bacillus Calmette-Guérin (BCG) vaccines against tuberculosis have been available for more than 90 years, their effectiveness has been hindered by variable protective efficacy and a lack of lasting memory responses. One factor contributing to this variability may be the diversity of the BCG strains that are used around the world, in part from genomic changes accumulated during vaccine production and their resulting differences in gene expression. We have compared the genomes and transcriptomes of a global collection of fourteen of the most widely used BCG strains at single base-pair resolution. We have also used quantitative proteomics to identify key differences in expression of proteins across five representative BCG strains of the four tandem duplication (DU) groups. We provide a comprehensive map of single nucleotide polymorphisms (SNPs), copy number variation and insertions and deletions (indels) across fourteen BCG strains. Genome-wide SNP characterization allowed the construction of a new and robust phylogenic genealogy of BCG strains. Transcriptional and proteomic profiling revealed a metabolic remodeling in BCG strains that may be reflected by altered immunogenicity and possibly vaccine efficacy. Together, these integrated-omic data represent the most comprehensive catalogue of genetic variation across a global collection of BCG strains.

  18. Bactericidal antibody against a representative epidemiological meningococcal serogroup B panel confirms that MATS underestimates 4CMenB vaccine strain coverage.

    Science.gov (United States)

    Frosi, Giacomo; Biolchi, Alessia; Lo Sapio, Morena; Rigat, Fabio; Gilchrist, Stefanie; Lucidarme, Jay; Findlow, Jamie; Borrow, Ray; Pizza, Mariagrazia; Giuliani, Marzia Monica; Medini, Duccio

    2013-10-09

    4CMenB (Bexsero), a vaccine developed against invasive meningococcal disease caused by capsular group B strains (MenB), was recently licensed for use by the European Medicines Agency. Assessment of 4CMenB strain coverage in specific epidemiologic settings is of primary importance to predict vaccination impact on the burden of disease. The Meningococcal Antigen Typing System (MATS) was developed to predict 4CMenB strain coverage, using serum bactericidal antibody assay with human complement (hSBA) data from a diverse panel of strains not representative of any specific epidemiology. To experimentally validate the accuracy of MATS-based predictions against strains representative of a specific epidemiologic setting. We used a stratified sampling method to identify a representative sample from all MenB disease isolates collected from England and Wales in 2007-2008, tested the strains in the hSBA assay with pooled sera from infant and adolescent vaccinees, and compared these results with MATS. MATS predictions and hSBA results were significantly associated (P=0.022). MATS predicted coverage of 70% (95% CI, 55-85%) was largely confirmed by 88% killing in the hSBA (95% CI, 72-95%). MATS had 78% accuracy and 96% positive predictive value against hSBA. MATS is a conservative predictor of strain coverage by the 4CMenB vaccine in infants and adolescents. Crown Copyright © 2013. Published by Elsevier Ltd. All rights reserved.

  19. Genomic expression catalogue of a global collection of BCG vaccine strains show evidence for highly diverged metabolic and cell-wall adaptations

    KAUST Repository

    Abdallah, Abdallah; Hill-Cawthorne, Grant A.; Otto, Thomas D.; Coll, Francesc; Guerra-Assunç ã o, José Afonso; Gao, Ge; Naeem, Raeece; Ansari, Hifzur Rahman; Malas, Tareq Majed Yasin; Adroub, Sabir; Verboom, Theo; Ummels, Roy; Zhang, Huoming; Panigrahi, Aswini Kumar; McNerney, Ruth; Brosch, Roland; Clark, Taane G.; Behr, Marcel A.; Bitter, Wilbert; Pain, Arnab

    2015-01-01

    Although Bacillus Calmette-Guérin (BCG) vaccines against tuberculosis have been available for more than 90 years, their effectiveness has been hindered by variable protective efficacy and a lack of lasting memory responses. One factor contributing to this variability may be the diversity of the BCG strains that are used around the world, in part from genomic changes accumulated during vaccine production and their resulting differences in gene expression. We have compared the genomes and transcriptomes of a global collection of fourteen of the most widely used BCG strains at single base-pair resolution. We have also used quantitative proteomics to identify key differences in expression of proteins across five representative BCG strains of the four tandem duplication (DU) groups. We provide a comprehensive map of single nucleotide polymorphisms (SNPs), copy number variation and insertions and deletions (indels) across fourteen BCG strains. Genome-wide SNP characterization allowed the construction of a new and robust phylogenic genealogy of BCG strains. Transcriptional and proteomic profiling revealed a metabolic remodeling in BCG strains that may be reflected by altered immunogenicity and possibly vaccine efficacy. Together, these integrated-omic data represent the most comprehensive catalogue of genetic variation across a global collection of BCG strains.

  20. Using reverse genetics to manipulate the NSs gene of the Rift Valley fever virus MP-12 strain to improve vaccine safety and efficacy.

    Science.gov (United States)

    Kalveram, Birte; Lihoradova, Olga; Indran, Sabarish V; Ikegami, Tetsuro

    2011-11-01

    Rift Valley fever virus (RVFV), which causes hemorrhagic fever, neurological disorders or blindness in humans, and a high rate abortion and fetal malformation in ruminants, has been classified as a HHS/USDA overlap select agent and a risk group 3 pathogen. It belongs to the genus Phlebovirus in the family Bunyaviridae and is one of the most virulent members of this family. Several reverse genetics systems for the RVFV MP-12 vaccine strain as well as wild-type RVFV strains, including ZH548 and ZH501, have been developed since 2006. The MP-12 strain (which is a risk group 2 pathogen and a non-select agent) is highly attenuated by several mutations in its M- and L-segments, but still carries virulent S-segment RNA, which encodes a functional virulence factor, NSs. The rMP12-C13type (C13type) carrying 69% in-frame deletion of NSs ORF lacks all the known NSs functions, while it replicates as efficient as does MP-12 in VeroE6 cells lacking type-I IFN. NSs induces a shut-off of host transcription including interferon (IFN)-beta mRNA and promotes degradation of double-stranded RNA-dependent protein kinase (PKR) at the post-translational level. IFN-beta is transcriptionally upregulated by interferon regulatory factor 3 (IRF-3), NF-kB and activator protein-1 (AP-1), and the binding of IFN-beta to IFN-alpha/beta receptor (IFNAR) stimulates the transcription of IFN-alpha genes or other interferon stimulated genes (ISGs), which induces host antiviral activities, whereas host transcription suppression including IFN-beta gene by NSs prevents the gene upregulations of those ISGs in response to viral replication although IRF-3, NF-kB and activator protein-1 (AP-1) can be activated by RVFV7. Thus, NSs is an excellent target to further attenuate MP-12, and to enhance host innate immune responses by abolishing the IFN-beta suppression function. Here, we describe a protocol for generating a recombinant MP-12 encoding mutated NSs, and provide an example of a screening method to identify

  1. Optimisation of strain selection in evolutionary continuous culture

    Science.gov (United States)

    Bayen, T.; Mairet, F.

    2017-12-01

    In this work, we study a minimal time control problem for a perfectly mixed continuous culture with n ≥ 2 species and one limiting resource. The model that we consider includes a mutation factor for the microorganisms. Our aim is to provide optimal feedback control laws to optimise the selection of the species of interest. Thanks to Pontryagin's Principle, we derive optimality conditions on optimal controls and introduce a sub-optimal control law based on a most rapid approach to a singular arc that depends on the initial condition. Using adaptive dynamics theory, we also study a simplified version of this model which allows to introduce a near optimal strategy.

  2. [An oral chemical vaccine from the hypertoxigenic strains of the causative agent of cholera KM-76 Inaba and KM-68 Ogawa].

    Science.gov (United States)

    Dzhaparidze, M N; Naumov, A V; Nikitina, G P; Meleshchenko, M V; Dobrova, G V; Zavorotnykh, V I; Gracheva, V P; Zakharova, T L

    1991-04-01

    The material on the development of chemical vaccine, prepared from two newly formed strains (KM-76 Inaba and KM-68 Ogawa) and intended for oral administration, is presented. The conditions for the submerged cultivation of these strains have been established, which makes it possible to increase the production of choleragen 8- to 10-fold and O-antigen 3- to 4-fold in comparison with V. cholerae natural strain 569B. The maximum accumulation of neuraminidase, protease, phospholipase, along with choleragen, has been registered in the logarithmic phase and that of O-antigen, in the stationary phase of growth. The use of strains KM-76 and KM-68 has led to the fourfold increase of the specific activity of the main immunogens, thus permitting the respective increase of the yield of the oral vaccine without changes in its high capacity for the formation of specific antibodies and its low residual toxigenicity.

  3. Meta-analysis of variables affecting mouse protection efficacy of whole organism Brucella vaccines and vaccine candidates

    Science.gov (United States)

    2013-01-01

    Background Vaccine protection investigation includes three processes: vaccination, pathogen challenge, and vaccine protection efficacy assessment. Many variables can affect the results of vaccine protection. Brucella, a genus of facultative intracellular bacteria, is the etiologic agent of brucellosis in humans and multiple animal species. Extensive research has been conducted in developing effective live attenuated Brucella vaccines. We hypothesized that some variables play a more important role than others in determining vaccine protective efficacy. Using Brucella vaccines and vaccine candidates as study models, this hypothesis was tested by meta-analysis of Brucella vaccine studies reported in the literature. Results Nineteen variables related to vaccine-induced protection of mice against infection with virulent brucellae were selected based on modeling investigation of the vaccine protection processes. The variable "vaccine protection efficacy" was set as a dependent variable while the other eighteen were set as independent variables. Discrete or continuous values were collected from papers for each variable of each data set. In total, 401 experimental groups were manually annotated from 74 peer-reviewed publications containing mouse protection data for live attenuated Brucella vaccines or vaccine candidates. Our ANOVA analysis indicated that nine variables contributed significantly (P-value Brucella vaccine protection efficacy: vaccine strain, vaccination host (mouse) strain, vaccination dose, vaccination route, challenge pathogen strain, challenge route, challenge-killing interval, colony forming units (CFUs) in mouse spleen, and CFU reduction compared to control group. The other 10 variables (e.g., mouse age, vaccination-challenge interval, and challenge dose) were not found to be statistically significant (P-value > 0.05). The protection level of RB51 was sacrificed when the values of several variables (e.g., vaccination route, vaccine viability, and

  4. Biofortification of folates in white wheat bread by selection of yeast strain and process.

    Science.gov (United States)

    Hjortmo, Sofia; Patring, Johan; Jastrebova, Jelena; Andlid, Thomas

    2008-09-30

    We here demonstrate that folate content in yeast fermented food can be dramatically increased by using a proper (i) yeast strain and (ii) cultivation procedure for the selected strain prior to food fermentation. Folate levels were 3 to 5-fold higher in white wheat bread leavened with a Saccharomyces cerevisiae strain CBS7764, cultured in defined medium and harvested in the respiro-fermentative phase of growth prior to dough preparation (135-139 microg/100 dry matter), compared to white wheat bread leavened with commercial Baker's yeast (27-43 microg/100 g). The commercial Baker's yeast strain had been industrially produced, using a fed-batch process, thereafter compressed and stored in the refrigerator until bakings were initiated. This strategy is an attractive alternative to fortification of bread with synthetically produced folic acid. By using a high folate producing strain cultured a suitable way folate levels obtained were in accordance with folic acid content in fortified cereal products.

  5. In silico analysis of Ta9 gene polymorphism in an Iranian Theileria annulata schizont-infected cell line S15 vaccine strain and native isolates

    Directory of Open Access Journals (Sweden)

    Habibi, G.

    2016-07-01

    Full Text Available Bovine theileriosis is a tick-borne disease caused by obligate intracellular parasites related to the genus Theileria. Cellular immune responses protect cattle against pathogens through the activation of immune cells. Nowadays, live, attenuated vaccine of Theileria annulata (T. annulata is being produced in Iran and is recommended for active cattle immunization. Detection of the immunogenic antigens and epitopes recognized by CD8+ T Lymphocytes is vital for the development of recombinant and subunit vaccines. Herein, sequences of the genes encoding Ta9, which is an important antigen recognized by bovine CD8+ T cells specific for T. annulata, in Iranian S15 vaccine strains, several Iranian isolates, as well as reference Ta9 DNA sequences registered in GeneBank were compared through polymerase chain reaction (PCR. The obtained data from DNA sequences were analyzed by using "Nucleotide", "Blast n", "BioEdit" and "IEDB" softwares. The results showed high level of variation in nucleotides and amino acids level. The observed polymorphism in Ta9 gene sequences of Iranian vaccine strains and some isolates from Iran demonstrated that this antigen contains polymorphic sequences and is active along with the specific major histocompatibility complex (MHC of the host. Polymorphic sequences and specific epitopes of Ta9 gene for CD8+ T cell provides an explanation for incomplete protection observed after inoculation of heterologous parasites in vaccinated cattle. These results have important implications for the application of Ta9 antigen for developing novel subunit vaccines.

  6. Immunoproteomic analysis of the human antibody response to natural tularemia infection with Type A or Type B strains or LVS vaccination

    Science.gov (United States)

    Fulton, Kelly M.; Zhao, Xigeng; Petit, Mireille D.; Kilmury, Sara L.N; Wolfraim, Lawrence A.; House, Robert V.; Sjostedt, Anders; Twine, Susan M.

    2011-01-01

    Francisella tularensis is pathogenic for many mammalian species including humans, causing a spectrum of diseases called tularemia. The highly virulent Type A strains have associated mortality rates of up to 60% if inhaled. An attenuated live vaccine strain (LVS) is the only vaccine to show efficacy in humans, but suffers several barriers to licensure, including the absence of a correlate of protection. An immunoproteomics approach was used to survey the repertoire of antibodies in sera from individuals who had contracted tularemia during two outbreaks and individuals from two geographical areas who had been vaccinated with NDBR Lot 11 or Lot 17 LVS. These data showed a large overlap in the antibodies generated in response to tularemia infection or LVS vaccination. A total of seven proteins were observed to be reactive with 60 % or more sera from vaccinees and convalescents. A further four proteins were recognised by 30–60 % of the sera screened. These proteins have the potential to serve as markers of vaccination or candidates for subunit vaccines. PMID:21873113

  7. Detection and differentiation of field and vaccine strains of canine distemper virus using reverse transcription followed by nested real time PCR (RT-nqPCR) and RFLP analysis.

    Science.gov (United States)

    Fischer, Cristine Dossin Bastos; Ikuta, Nilo; Canal, Cláudio Wageck; Makiejczuk, Aline; Allgayer, Mariangela da Costa; Cardoso, Cristine Hoffmeister; Lehmann, Fernanda Kieling; Fonseca, André Salvador Kazantzi; Lunge, Vagner Ricardo

    2013-12-01

    Canine distemper virus (CDV) is the cause of a severe and highly contagious disease in dogs. Practical diagnosis of canine distemper based on clinical signs and laboratory tests are required to confirm CDV infection. The present study aimed to develop a molecular assay to detect and differentiate field and vaccine CDV strains. Reverse transcription followed by nested real time polymerase chain reaction (RT-nqPCR) was developed, which exhibited analytical specificity (all the samples from healthy dogs and other canine infectious agents were not incorrectly detected) and sensitivity (all replicates of a vaccine strain were positive up to the 3125-fold dilution - 10(0.7) TCID50). RT-nqPCR was validated for CDV detection on different clinical samples (blood, urine, rectal and conjunctival swabs) of 103 animals suspected to have distemper. A total of 53 animals were found to be positive based on RT-nqPCR in at least one clinical sample. Blood resulted in more positive samples (50 out of 53, 94.3%), followed by urine (44/53, 83.0%), rectal (38/53, 71%) and conjunctival (27/53, 50.9%) swabs. A commercial immunochromatography (IC) assay had detected CDV in only 30 conjunctival samples of these positive dogs. Nucleoprotein (NC) gene sequencing of 25 samples demonstrated that 23 of them were closer to other Brazilian field strains and the remaining two to vaccine strains. A single nucleotide sequences difference, which creates an Msp I restriction enzyme digestion, was used to differentiate between field and vaccine CDV strains by restriction fragment length polymorphism (RFLP) analysis. The complete assay was more sensitive than was IC for the detection of CDV. Blood was the more frequently positive specimen and the addition of a restriction enzyme step allowed the differentiation of vaccine and Brazilian field strains. Copyright © 2013 Elsevier B.V. All rights reserved.

  8. Human vaccination against Plasmodium vivax Duffy-binding protein induces strain-transcending antibodies

    OpenAIRE

    Payne, Ruth O.; Silk, Sarah E.; Elias, Sean C.; Milne, Kathryn H.; Rawlinson, Thomas A.; Llewellyn, David; Shakri, A. Rushdi; Jin, Jing; Labb?, Genevi?ve M.; Edwards, Nick J.; Poulton, Ian D.; Roberts, Rachel; Farid, Ryan; J?rgensen, Thomas; Alanine, Daniel G.W.

    2017-01-01

    BACKGROUND: Plasmodium vivax is the most widespread human malaria geographically; however, no effective vaccine exists. Red blood cell invasion by the P. vivax merozoite depends on an interaction between the Duffy antigen receptor for chemokines (DARC) and region II of the parasite's Duffy-binding protein (PvDBP_RII). Naturally acquired binding-inhibitory antibodies against this interaction associate with clinical immunity, but it is unknown whether these responses can be induced by human vac...

  9. Genetic Diversity of Circulating Rotavirus Strains in Tanzania Prior to the Introduction of Vaccination

    Science.gov (United States)

    Moyo, Sabrina J.; Blomberg, Bjørn; Hanevik, Kurt; Kommedal, Oyvind; Vainio, Kirsti; Maselle, Samuel Y.; Langeland, Nina

    2014-01-01

    Background Tanzania currently rolls out vaccination against rotavirus-diarrhea, a major cause of child illness and death. As the vaccine covers a limited number of rotavirus variants, this study describes the molecular epidemiology of rotavirus among children under two years in Dar es Salaam, Tanzania, prior to implementation of vaccination. Methods Stool specimens, demographic and clinical information, were collected from 690 children admitted to hospital due to diarrhea (cases) and 545 children without diarrhea (controls) during one year. Controls were inpatient or children attending child health clinics. Rotavirus antigen was detected using ELISA and positive samples were typed by multiplex semi-nested PCR and sequencing. Results The prevalence of rotavirus was higher in cases (32.5%) than in controls (7.7%, Protavirus prevalence was higher in cool (23.9%) than hot months (17.1%) of the year (P = 0.012). We also observed significant seasonal variation of G genotypes. Rotavirus was most frequently found in the age group of four to six months. The prevalence of rotavirus in cases was lower in stunted children (28.9%) than in non-stunted children (40.1%, P = 0.003) and lower in HIV-infected (15.4%, 4/26) than in HIV-uninfected children (55.3%, 42/76, PRotavirus infection and circulating genotypes showed seasonal variation. This study also suggests that rotavirus may not be an opportunistic pathogen in children infected with HIV. PMID:24844631

  10. Antagonistic Activity of Lactobacillus reuteri Strains on the Adhesion Characteristics of Selected Pathogens

    OpenAIRE

    Singh, Tejinder P.; Kaur, Gurpreet; Kapila, Suman; Malik, Ravinder K.

    2017-01-01

    Adhesion ability of probiotics is the key factor that decides their colonization in the gastrointestinal tract and potential to inhibit pathogens. Therefore, adhesion ability can be considered as a key determinant for probiotic efficacy. Presents study documents the antagonistic activity of viable/untreated, Lithium chloride (LiCl) treated or heat-killed forms of eight probiotic Lactobacillus reuteri strains on the adhesion characteristics of selected pathogens. All strains investigated were ...

  11. Comparative evaluation of live marker vaccine candidates "CP7_E2alf" and "flc11" along with C-strain "Riems" after oral vaccination

    NARCIS (Netherlands)

    Blome, S.; Aebischer, A.; Lange, E.; Hofmann, M.; Leifer, I.; Loeffen, W.L.A.; Koenen, F.; Beer, M.

    2012-01-01

    Due to the tremendous socio-economic impact of classical swine fever (CSF) outbreaks, emergency vaccination scenarios are continuously under discussion. Unfortunately, all currently available vaccines show restrictions either in terms of marker capacities or immunogenicity. Recent research efforts

  12. Molecular characterization of canine parvovirus strains in Argentina: Detection of the pathogenic variant CPV2c in vaccinated dogs.

    Science.gov (United States)

    Calderon, Marina Gallo; Mattion, Nora; Bucafusco, Danilo; Fogel, Fernando; Remorini, Patricia; La Torre, Jose

    2009-08-01

    PCR amplification with sequence-specific primers was used to detect canine parvovirus (CPV) DNA in 38 rectal swabs from Argentine domestic dogs with symptoms compatible with parvovirus disease. Twenty-seven out of 38 samples analyzed were CPV positive. The classical CPV2 strain was not detected in any of the samples, but nine samples were identified as CPV2a variant and 18 samples as CPV2b variant. Further sequence analysis revealed a mutation at amino acid 426 of the VP2 gene (Asp426Glu), characteristic of the CPV2c variant, in 14 out of 18 of the samples identified initially by PCR as CPV2b. The appearance of CPV2c variant in Argentina might be dated at least to the year 2003. Three different pathogenic CPV variants circulating currently in the Argentine domestic dog population were identified, with CPV2c being the only variant affecting vaccinated and unvaccinated dogs during the year 2008.

  13. Evaluation of 793/B-like and Mass-like vaccine strain kinetics in experimental and field conditions by real-time RT-PCR quantification.

    Science.gov (United States)

    Tucciarone, C M; Franzo, G; Berto, G; Drigo, M; Ramon, G; Koutoulis, K C; Catelli, E; Cecchinato, M

    2018-01-01

    Infectious bronchitis virus (IBV) is a great economic burden both for productive losses and costs of the control strategies. Many different vaccination protocols are applied in the same region and even in consecutive cycles on the same farm in order to find the perfect balance between costs and benefits. In Northern Italy, the usual second vaccination is more and more often moved up to the chick's first d of life. The second strain administration together with the common Mass priming by spray at the hatchery allows saving money and time and reducing animal stress. The present work compared the different vaccine strains (Mass-like or B48, and 1/96) kinetics both in field conditions and in a 21-day-long experimental trial in broilers, monitoring the viral replication by upper respiratory tract swabbing and vaccine specific real time reverse transcription PCR (RT-PCR) quantification. In both field and experimental conditions, titers for all the vaccines showed an increasing trend in the first 2 wk and then a decrease, though still remaining detectable during the whole monitored period. IBV field strain and avian Metapneumovirus (aMPV) presence also was also investigated by RT-PCR and sequencing, and by multiplex real-time RT-PCR, respectively, revealing a consistency in the pathogen introduction timing at around 30 d, in correspondence with the vaccine titer's main decrease. These findings suggest the need for an accurate knowledge of live vaccine kinetics, whose replication can compete with the other pathogen one, providing additional protection to be added to what is conferred by the adaptive immune response. © 2017 Poultry Science Association Inc.

  14. The NS3 proteins of global strains of bluetongue virus evolve into regional topotypes through negative (purifying) selection.

    Science.gov (United States)

    Balasuriya, U B R; Nadler, S A; Wilson, W C; Pritchard, L I; Smythe, A B; Savini, G; Monaco, F; De Santis, P; Zhang, N; Tabachnick, W J; Maclachlan, N J

    2008-01-01

    Comparison of the deduced amino acid sequences of the genes (S10) encoding the NS3 protein of 137 strains of bluetongue virus (BTV) from Africa, the Americas, Asia, Australia and the Mediterranean Basin showed limited variation. Common to all NS3 sequences were potential glycosylation sites at amino acid residues 63 and 150 and a cysteine at residue 137, whereas a cysteine at residue 181 was not conserved. The PPXY and PS/TAP late-domain motifs were conserved in all but three of the viruses. Phylogenetic analyses of these same sequences yielded two principal clades that grouped the viruses irrespective of their serotype or year of isolation (1900-2003). All viruses from Asia and Australia were grouped in one clade, whereas those from the other regions were present in both clades. Each clade segregated into distinct subclades that included viruses from single or multiple regions, and the S10 genes of some field viruses were identical to those of live-attenuated BTV vaccines. There was no evidence of positive selection on the S10 gene as assessed by reconstruction of ancestral codon states on the phylogeny, rather the functional constraints of the NS3 protein are expressed through substantial negative (purifying) selection.

  15. Immunomagnetic separation combined with colony immunoblotting for selective enrichment and detection of piliated Lactobacillus rhamnosus strains.

    Science.gov (United States)

    Yang, Z Q; Wei, Y F; Rao, S Q; Gao, L; Yin, Y Q; Xue, F; Fang, W M; Gu, R X; Jiao, X A

    2016-11-01

    Piliated Lactobacillus rhamnosus (pLR) strains have attracted much attention owing to their excellent mucus adhering capacity and immunomodulatory effects. Here, we aimed to develop a rapid, sensitive method for isolating pLR strains in complex ecosystems using immunomagnetic separation (IMS) with colony immunoblotting (CIB). Magnetic nanobeads (diameter: 180 nm) conjugated with anti-pLR SpaA pilin antibodies (anti-SpaA) were prepared and used to preconcentrate pLR strains in samples, followed by confirmation with anti-SpaA-based CIB analysis. Under optimized experimental conditions, IMS-CIB selectively recovered pLR strains from 10 7  CFU ml -1 of faecal microbiota samples spiked with 2·9 × 10 1 to 2·4 × 10 6  CFU ml -1 of pLR strains. No positive colonies were detected in samples without addition of pLR strains. The detection limit of IMS-CIB was 29 CFU pLR ml -1 of faecal microbiota, which is much lower than that of CIB without IMS preconcentration (2·0 × 10 4  CFU ml -1 ). IMS-CIB allowed selective preconcentration of pLR strains in highly heterogeneous bacterial suspensions and direct detection of pLR colonies, which remained readily available for subsequent isolation. Our findings established an effective method for selective enrichment and detection of pLR strains. © 2016 The Society for Applied Microbiology.

  16. Selection of Bacillus thuringiensis strains toxic to cotton boll weevil (Anthonomus grandis, Coleoptera: Curculionidae) larvae.

    Science.gov (United States)

    Pérez, Melisa P; Sauka, Diego H; Onco, María I; Berretta, Marcelo F; Benintende, Graciela B

    Preliminary bioassays with whole cultures (WC) of 124 Bacillus thuringiensis strains were performed with neonate larvae of Anthonomus grandis, a major cotton pest in Argentina and other regions of the Americas. Three exotic and four native strains were selected for causing more than 50% mortality. All of them were β-exotoxin producers. The native strains shared similar morphology of parasporal crystals, similar protein pattern and identical insecticidal gene profiles. These features resembled Lepidoptera-toxic strains. Furthermore, these strains showed a Rep-PCR pattern identical to lepidoptericidal strain HD-1, suggesting that these strains may belong to serovar kurstaki. However, some differences were observed in the plasmid profiles and in the production of β-exotoxin. To determine the culture fractions where the insecticidal metabolites were present, bioassays including resuspended spore-crystal pellets, filtered supernatants (FS) were compared with those of WC. Both fractions tested showed some level of insecticidal activity. The results may suggest that the main toxic factors can be found in FS and could be directly correlated with the presence of β-exotoxin. Based on the bioassays with FS and autoclaved FS, the participation of thermolabile virulence factors such as Cry1I in toxicity is neither discarded. In the selected strains, β-exotoxin would be the major associated virulence factor; therefore, their use in biological control of A. grandis should be restricted. Nevertheless, these strains could be the source of genes (e.g., cry1Ia) to produce transgenic cotton plants resistant to this pest. Copyright © 2017 Asociación Argentina de Microbiología. Publicado por Elsevier España, S.L.U. All rights reserved.

  17. Relation Between Motility, Accelerated Aging and Gene Expression in Selected Drosophila Strains under Hypergravity Conditions

    Science.gov (United States)

    Serrano, Paloma; van Loon, Jack J. W. A.; Medina, F. Javier; Herranz, Raúl

    2013-02-01

    Motility and aging in Drosophila have proven to be highly modified under altered gravity conditions (both in space and ground simulation facilities). In order to find out how closely connected they are, five strains with altered geotactic response or survival rates were selected and exposed to an altered gravity environment of 2 g. By analysing the different motile and behavioural patterns and the median survival rates, we show that altered gravity leads to changes in motility, which will have a negative impact on the flies' survival. Previous results show a differential gene expression between sessile samples and adults and confirm that environmentally-conditioned behavioural patterns constrain flies' gene expression and life span. Therefore, hypergravity is considered an environmental stress factor and strains that do not respond to this new environment experience an increment in motility, which is the major cause for the observed increased mortality also under microgravity conditions. The neutral-geotaxis selected strain (strain M) showed the most severe phenotype, unable to respond to variations in the gravitational field. Alternatively, the opposite phenotype was observed in positive-geotaxis and long-life selected flies (strains B and L, respectively), suggesting that these populations are less sensitive to alterations in the gravitational load. We conclude that the behavioural response has a greater contribution to aging than the modified energy consumption in altered gravity environments.

  18. Growth kinetic and fuel quality parameters as selective criterion for screening biodiesel producing cyanobacterial strains.

    Science.gov (United States)

    Gayathri, Manickam; Shunmugam, Sumathy; Mugasundari, Arumugam Vanmathi; Rahman, Pattanathu K S M; Muralitharan, Gangatharan

    2018-01-01

    The efficiency of cyanobacterial strains as biodiesel feedstock varies with the dwelling habitat. Fourteen indigenous heterocystous cyanobacterial strains from rice field ecosystem were screened based on growth kinetic and fuel parameters. The highest biomass productivity was obtained in Nostoc punctiforme MBDU 621 (19.22mg/L/day) followed by Calothrix sp. MBDU 701 (13.43mg/L/day). While lipid productivity and lipid content was highest in Nostoc spongiaeforme MBDU 704 (4.45mg/L/day and 22.5%dwt) followed by Calothrix sp. MBDU 701 (1.54mg/L/day and 10.75%dwt). Among the tested strains, Nostoc spongiaeforme MBDU 704 and Nostoc punctiforme MBDU 621 were selected as promising strains for good quality biodiesel production by Preference Ranking Organization Method for Enrichment Evaluation (PROMETHEE) and Graphical Analysis for Interactive Assistance (GAIA) analysis. Copyright © 2017 Elsevier Ltd. All rights reserved.

  19. Selection of yeast starter culture strains for the production of marula fruit wines and distillates.

    Science.gov (United States)

    Fundira, M; Blom, M; Pretorius, I S; van Rensburg, P

    2002-03-13

    Juice of the Sclerocarya birrea subsp. caffra (marula) fruit was fermented by indigenous microflora and different commercial Saccharomyces cerevisiae yeast strains at different temperatures, namely, 15 and 30 degrees C. Volatile acids, esters, and higher alcohols were quantified in the wine and distillates, and the results were interpreted using a multivariate analysis of variance and an average linkage cluster analysis. Significant differences between 15 and 30 degrees C and also among yeasts with respect to volatile compounds were observed. Yeast strains VIN7 and FC consistently produced wines and final distillates significantly different from the other strains. A panel of tasters and marula and brandy producers was asked to select wines and distillates that had an acceptable and typical marula "nose". They were also asked to detect the differences among wines and distillates fermented with the same yeast strain at different temperatures.

  20. Newcastle disease B1 vaccine strain in wild rock pigeons in Atlanta, Georgia

    Science.gov (United States)

    From June to October of 2012, samples were collected from wild Rock Pigeons (Columba livia) in urban neighborhoods of Atlanta, Georgia to ascertain the prevalence of pigeon paramyxovirus serotype-1 (PPMV-1). PPMV-1 strains are a subset of avian paramyxovirus serotype-1 (APMV-1) commonly isolated fro...

  1. Safety and immunogenicity of inactivated poliovirus vaccine based on Sabin strains with and without aluminum hydroxide: a phase I trial in healthy adults.

    Science.gov (United States)

    Verdijk, Pauline; Rots, Nynke Y; van Oijen, Monique G C T; Oberste, M Steven; Boog, Claire J; Okayasu, Hiromasa; Sutter, Roland W; Bakker, Wilfried A M

    2013-11-12

    An inactivated poliovirus vaccine (IPV) based on attenuated poliovirus strains (Sabin-1, -2 and -3) was developed for technology transfer to manufacturers in low- and middle income countries in the context of the Global Polio Eradication Initiative. Safety and immunogenicity of the Sabin-IPV was evaluated in a double-blind, randomized, controlled, phase I 'proof-of-concept' trial. Healthy male adults received a single intramuscular injection with Sabin-IPV, Sabin-IPV adjuvanted with aluminum hydroxide or conventional IPV. Virus-neutralizing titers against both Sabin and wild poliovirus strains were determined before and 28 days after vaccination. No vaccine-related serious adverse events were observed, and all local and systemic reactions were mild or moderate and transient. In all subjects, an increase in antibody titer for all types of poliovirus (both Sabin and wild strains) was observed 28 days after vaccination. Sabin-IPV and Sabin-IPV adjuvanted with aluminum hydroxide administered as a booster dose were equally immunogenic and safe as conventional IPV. EudraCTnr: 2010-024581-22, NCT01708720. Copyright © 2013 Elsevier Ltd. All rights reserved.

  2. Relation between motility, accelerated aging and gene expression in selected Drosophila strains under hypergravity conditions

    NARCIS (Netherlands)

    Serrano, P.; van Loon, J.J.W.A.; Javier Medina, F.; Herranz, R.

    2013-01-01

    Motility and aging in Drosophila have proven to be highly modified under altered gravity conditions (both in space and ground simulation facilities). In order to find out how closely connected they are, five strains with altered geotactic response or survival rates were selected and exposed to an

  3. Improving the selection and development of influenza vaccine viruses - Report of a WHO informal consultation on improving influenza vaccine virus selection, Hong Kong SAR, China, 18-20 November 2015.

    Science.gov (United States)

    Hampson, Alan; Barr, Ian; Cox, Nancy; Donis, Ruben O; Siddhivinayak, Hirve; Jernigan, Daniel; Katz, Jacqueline; McCauley, John; Motta, Fernando; Odagiri, Takato; Tam, John S; Waddell, Anthony; Webby, Richard; Ziegler, Thedi; Zhang, Wenqing

    2017-02-22

    Since 2010 the WHO has held a series of informal consultations to explore ways of improving the currently highly complex and time-pressured influenza vaccine virus selection and development process. In November 2015 experts from around the world met to review the current status of efforts in this field. Discussion topics included strengthening influenza surveillance activities to increase the availability of candidate vaccine viruses and improve the extent, timeliness and quality of surveillance data. Consideration was also given to the development and potential application of newer laboratory assays to better characterize candidate vaccine viruses, the potential importance of antibodies directed against influenza virus neuraminidase, and the role of vaccine effectiveness studies. Advances in next generation sequencing and whole genome sequencing of influenza viruses were also discussed, along with associated developments in synthetic genomics technologies, evolutionary analysis and predictive mathematical modelling. Discussions were also held on the late emergence of an antigenic variant influenza A(H3N2) virus in mid-2014 that could not be incorporated in time into the 2014-15 northern hemisphere vaccine. There was broad recognition that given the current highly constrained influenza vaccine development and production timeline it would remain impossible to incorporate any variant virus which emerged significantly long after the relevant WHO biannual influenza vaccine composition meetings. Discussions were also held on the development of pandemic and broadly protective vaccines, and on associated regulatory and manufacturing requirements and constraints. With increasing awareness of the health and economic burdens caused by seasonal influenza, the ever-present threat posed by zoonotic influenza viruses, and the significant impact of the 2014-15 northern hemisphere seasonal influenza vaccine mismatch, this consultation provided a very timely opportunity to share

  4. Characterization of the Burkholderia mallei tonB Mutant and Its Potential as a Backbone Strain for Vaccine Development.

    Directory of Open Access Journals (Sweden)

    Tiffany M Mott

    Full Text Available In this study, a Burkholderia mallei tonB mutant (TMM001 deficient in iron acquisition was constructed, characterized, and evaluated for its protective properties in acute inhalational infection models of murine glanders and melioidosis.Compared to the wild-type, TMM001 exhibits slower growth kinetics, siderophore hyper-secretion and the inability to utilize heme-containing proteins as iron sources. A series of animal challenge studies showed an inverse correlation between the percentage of survival in BALB/c mice and iron-dependent TMM001 growth. Upon evaluation of TMM001 as a potential protective strain against infection, we found 100% survival following B. mallei CSM001 challenge of mice previously receiving 1.5 x 10(4 CFU of TMM001. At 21 days post-immunization, TMM001-treated animals showed significantly higher levels of B. mallei-specific IgG1, IgG2a and IgM when compared to PBS-treated controls. At 48 h post-challenge, PBS-treated controls exhibited higher levels of serum inflammatory cytokines and more severe pathological damage to target organs compared to animals receiving TMM001. In a cross-protection study of acute inhalational melioidosis with B. pseudomallei, TMM001-treated mice were significantly protected. While wild type was cleared in all B. mallei challenge studies, mice failed to clear TMM001.Although further work is needed to prevent chronic infection by TMM001 while maintaining immunogenicity, our attenuated strain demonstrates great potential as a backbone strain for future vaccine development against both glanders and melioidosis.

  5. Head-to-head immunogenicity comparison of Edmonston-Zagreb vs. AIK-C measles vaccine strains in infants aged 8-12 months: A randomized clinical trial.

    Science.gov (United States)

    Izadi, Shahrokh; Zahraei, Seyed Mohsen; Salehi, Masoud; Mohammadi, Mahdi; Tabatabaei, Seyed Mehdi; Mokhtari-Azad, Talat

    2018-01-29

    A non-inferiority multi-centre parallel randomized double-blind trial was implemented in Zahedan district, Sistan-va-Baluchestan province, Iran, to compare the performance of the two measles vaccines which are in use in the National Immunization Programme of Iran and are of two different measles virus vaccine strains: Edmonston-Zagreb (EZ) strain vs. AIK-C strain. The main outcome measure was appearance of anti-measles antibody in sera. 200 infants, 8-12 months old, whose parents consented for their children to be included in the study, were randomized in permutation blocks of size 4-8 in four Urban Health Clinics. Having given a pre-vaccination blood sample, they received measles-rubella vaccine containing one of the vaccine strains mentioned before. After 60 days, the second blood sample was taken. The sera of the pre- and post-vaccination blood samples were tested for anti-measles antibodies in the National Reference Measles Laboratory. Parents, laboratory technicians and statistician were blind to groupings. Of the 200 children equally randomized in the two arms, 185 who were seronegative before vaccination (88 in the EZ arm and 97 in the AIK-C arm) were entered in the final analysis. The seroconversion rate in the EZ arm was 76.1% (95% CI: 60.2-85.2%), and that in the AIK-C arm was 58.7%; (95% CI: 48.8-68.7%). The absolute rate difference was 17. 4% (4.1-30.9%; P-value: .012), and the relative seroconversion rate of EZ to AIK-C was 1.3 (95% CI: 1.1-1.6; P-value: .012). No adverse events were reported during the study period. A considerable difference in the seropositivity of different measles containing vaccines could be demonstrated in the first year of life. Iranian Registry of Clinical Trials Registration Number: IRCT2016032827144N1; May 10, 2016 (www.who.int/ictrp/network/irct/en/). Copyright © 2017 Elsevier Ltd. All rights reserved.

  6. CLINICAL STUDIES OF REACTOGENICITY, SAFETY AND IMMUNOGENICITY OF LIVE MONOVALENT INFLUENZA VACCINE (STRAIN А/17/CALIFORNIA/2009/38 — H1N1 IN CHILDREN

    Directory of Open Access Journals (Sweden)

    D.S. Bushmenkov

    2010-01-01

    Full Text Available Results of performed pre-clinical and clinical studies with volunteers 18-60 years old allowed registration of vaccine «INFLUVIR» (live monovalent vaccine for the prophylaxis of influenza A/H1N1, strain A/17/California/2009/38 (H1N1, developed by NPO «Microgen» in Russian Federation so timely vaccination campaign was performed. As a result, the level of morbidity with influenza A/H1N1 in Russia was decreased, and development of complication was prevented. Clinical studies in different groups of children were performed for the purpose of widening indications for vaccine «INFLUVIR» administration. According to the results of studies vaccine «INFLUVIR» has good tolerability and safety, low reactogenicity, and significant immunogenicity. This fact will allow changing of present normative documentation and administration of «INFLUVIR» in children of different age for prophylaxis of influenza A/H1N1.Key words: children, influenza, virus A/H1N1, live influenza vaccine, tolerability, safety, immunogenicity.(Voprosy sovremennoi pediatrii — Current Pediatrics. – 2010;9(4:101-105

  7. Cell-mediated and humoral immune responses induced by scarification vaccination of human volunteers with a new lot of the live vaccine strain of Francisella tularensis.

    Science.gov (United States)

    Waag, D M; Galloway, A; Sandstrom, G; Bolt, C R; England, M J; Nelson, G O; Williams, J C

    1992-01-01

    Tularemia is a disease caused by the facultative intracellular bacterium Francisella tularensis. We evaluated a new lot of live F. tularensis vaccine for its immunogenicity in human volunteers. Scarification vaccination induced humoral and cell-mediated immune responses. Indications of a positive immune response after vaccination included an increase in specific antibody levels, which were measured by enzyme-linked immunosorbent and immunoblot assays, and the ability of peripheral blood lymphocytes to respond to whole F. tularensis bacteria as recall antigens. Vaccination caused a significant rise (P less than 0.05) in immunoglobulin A (IgA), IgG, and IgM titers. Lymphocyte stimulation indices were significantly increased (P less than 0.01) in vaccinees 14 days after vaccination. These data verify that this new lot of live F. tularensis vaccine is immunogenic. Images PMID:1400988

  8. [Influence of distinct criteria for selecting patients for swabbing on estimation of the effectiveness of the influenza vaccine].

    Science.gov (United States)

    Martínez-Baz, Iván; Guevara, Marcela; Elía, Fernando; Ezpeleta, Carmen; Fernández Alonso, Mirian; Castilla, Jesús

    2014-01-01

    To estimate the effectiveness of the influenza vaccine under different criteria for selecting patients for swabbing. A case-control study was performed of laboratory-confirmed cases (n=909) and negative controls for influenza (n=732) in the 2010-2011 to 2012-2013 seasons in Navarre (Spain). The adjusted vaccine effectiveness was estimated by including all swabs from patients with influenza-like-illness and selecting only the first two cases per physician and week. The first two patients per physician and week were less frequently vaccinated against influenza (7.9% vs. 12.5%, p=0.021) and less often received confirmation of influenza (53.6% vs. 66.4%, p <0.001) than subsequent patients. These differences decreased after adjustment for covariates. The effectiveness of the influenza vaccine was 49% (95% CI: 23-66%) when all swabs were included and was 55% (95% CI: 27-72%) when we selected the first two swabs per week and physician. The selection of the first two patients per physician and week may bias assessment of the effectiveness of the influenza vaccine, although this bias was small in the seasons analyzed. Copyright © 2013 SESPAS. Published by Elsevier Espana. All rights reserved.

  9. Genetic structure of human A/H1N1 and A/H3N2 influenza virus on Corsica Island: phylogenetic analysis and vaccine strain match, 2006-2010.

    Directory of Open Access Journals (Sweden)

    Alessandra Falchi

    Full Text Available BACKGROUND: The aim of this study was to analyse the genetic patterns of Hemagglutinin (HA genes of influenza A strains circulating on Corsica Island during the 2006-2009 epidemic seasons and the 2009-2010 pandemic season. METHODS: Nasopharyngeal samples from 371 patients with influenza-like illness (ILI were collected by General Practitioners (GPs of the Sentinelles Network through a randomised selection routine. RESULTS: Phylogenetic analysis of HA revealed that A/H3N2 strains circulating on Corsica were closely related to the WHO recommended vaccine strains in each analyzed season (2006-2007 to 2008-2009. Seasonal Corsican influenza A/H1N1 isolated during the 2007-2008 season had drifted towards the A/Brisbane/59/2007 lineage, the A/H1N1 vaccine strain for the 2008-2009 season. The A/H1N1 2009 (A/H1N1pdm strains isolated on Corsica Island were characterized by the S220T mutation specific to clade 7 isolates. It should be noted that Corsican isolates formed a separate sub-clade of clade 7 as a consequence of the presence of the fixed substitution D222E. The percentages of the perfect match vaccine efficacy, estimated by using the p(epitope model, against influenza viruses circulating on Corsica Island varied substantially across the four seasons analyzed, and tend to be highest for A/H1N1 compared with A/H3N2 vaccines, suggesting that cross-immunity seems to be stronger for the H1 HA gene. CONCLUSION: The molecular analysis of the HA gene of influenza viruses that circulated on Corsica Island between 2006-2010 showed for each season the presence of a dominant lineage characterized by at least one fixed mutation. The A/H3N2 and A/H1N1pdm isolates were characterized by multiples fixation at antigenic sites. The fixation of specific mutations at each outbreak could be explained by the combination of a neutral phenomenon and a founder effect, favoring the presence of a dominant lineage in a closed environment such as Corsica Island.

  10. Isolation and Fatty Acid Profile of Selected Microalgae Strains from the Red Sea for Biofuel Production

    Directory of Open Access Journals (Sweden)

    Khalid M. Abu-Salah

    2013-05-01

    Full Text Available The isolation of lipid-rich autochthonous strains of microalgae is a crucial stage for the development of a microalgae-based biofuel production plant, as these microalgae already have the necessary adaptations to withstand competition, predation and the temperatures observed at each production site. This is particularly important in extreme climates such as in Saudi Arabia. Resorting to fluorescence activated cell sorting (FACS we screened for and isolated several microalgal strains from samples collected from the Red Sea. Relying on the fluorescence of BODIPY 505/515 (4,4-difluoro-1,3,5,7-tetramethyl-4-bora-3a,4a-diazasindacene and growth performance, four promising candidates were identified and the total lipid content and fatty acid profile was assessed for biofuels production. Selected isolates were classified as chlorophytes, belonging to three different genera: Picochlorum, Nannochloris and Desmochloris. The lipid contents were assessed microscopically by means of BODIPY 505/515-associated fluorescence to detect intracellular lipid bodies, which revealed several lipid drops in all selected strains. This result was confirmed by lipid gravimetric determination, which demonstrated that all strains under study presented inner cell lipid contents ranging from 20% to 25% of the biomass dry weight. Furthermore, the fatty acid methyl esters profile of all strains seems ideal for biodiesel production due to a low degree of polyunsaturated fatty acid methyl esters and high amount of palmitic and oleic acids.

  11. Efficacy of selected Pseudomonas strains for biocontrol of Rhizoctonia solani in potato

    Directory of Open Access Journals (Sweden)

    Moncef MRABET

    2014-01-01

    Full Text Available Thirty seven bacterial isolates from faba bean (Vicia faba L. root-nodules were screened for their antagonistic activity against eight Rhizoctonia solani strains isolated from infected potato (Solanum tuberosum L. tubers. Two bacterial strains (designated as Kl.Fb14 and S8.Fb11 gave 50% in vitro inhibition of R. solani mycelial growth. 16S rDNA sequence analysis indicated that strain Kl.Fb14 exhibited 99.5% identity with Pseudomonas moraviensis, and that S8.Fb11 exhibited 99.8% identity with Pseudomonas reinekei. Greenhouse trials in soil showed that strain S8.Fb11 reduced the percentage of sclerotia on potato tubers and amounts of tuber infection for the potato cultivars Spunta and Nicola. In a field trial conducted in South Tunisia, infection with R. solani reduced potato yield by approximately 40% for ‘Spunta’ and 17% for ‘Nicola’; about 20% of the total tuber production was severely infected. However, when potato tubers were treated with strain S8.Fb11 prior to sowing, disease incidence was reduced to 6% of total production with low infection levels; potato yield was enhanced by about 6 kg per 10 m row in comparison to R. solani infected plants. The second selected Pseudomonas sp. (strain Kl.Fb14 did not affect either the levels of sclerotia on tubers or potato yield.

  12. Determination of Strain Rate Sensitivity of Micro-struts Manufactured Using the Selective Laser Melting Method

    Science.gov (United States)

    Gümrük, Recep; Mines, R. A. W.; Karadeniz, Sami

    2018-03-01

    Micro-lattice structures manufactured using the selective laser melting (SLM) process provides the opportunity to realize optimal cellular materials for impact energy absorption. In this paper, strain rate-dependent material properties are measured for stainless steel 316L SLM micro-lattice struts in the strain rate range of 10-3 to 6000 s-1. At high strain rates, a novel version of the split Hopkinson Bar has been developed. Strain rate-dependent materials data have been used in Cowper-Symonds material model, and the scope and limit of this model in the context of SLM struts have been discussed. Strain rate material data and the Cowper-Symonds model have been applied to the finite element analysis of a micro-lattice block subjected to drop weight impact loading. The model output has been compared to experimental results, and it has been shown that the increase in crush stress due to impact loading is mainly the result of strain rate material behavior. Hence, a systematic methodology has been developed to investigate the impact energy absorption of a micro-lattice structure manufactured using additive layer manufacture (SLM). This methodology can be extended to other micro-lattice materials and configurations, and to other impact conditions.

  13. Control selection and confounding factors: A lesson from a Japanese case-control study to examine acellular pertussis vaccine effectiveness.

    Science.gov (United States)

    Ohfuji, Satoko; Okada, Kenji; Nakano, Takashi; Ito, Hiroaki; Hara, Megumi; Kuroki, Haruo; Hirota, Yoshio

    2017-08-24

    When using a case-control study design to examine vaccine effectiveness, both the selection of control subjects and the consideration of potential confounders must be the important issues to ensure accurate results. In this report, we described our experience from a case-control study conducted to evaluate the effectiveness of acellular pertussis vaccine combined with diphtheria-tetanus toxoids (DTaP vaccine). Newly diagnosed pertussis cases and age- and sex-matched friend-controls were enrolled, and the history of DTaP vaccination was compared between groups. Logistic regression models were used to calculate odds ratios (ORs) and 95% confidence intervals (CIs) of vaccination for development of pertussis. After adjustment for potential confounders, four doses of DTaP vaccination showed a lower OR for pediatrician-diagnosed pertussis (OR=0.11, 95% CI, 0.01-0.99). In addition, the decreasing OR of four doses vaccination was more pronounced for laboratory-confirmed pertussis (OR=0.07, 95%CI, 0.01-0.82). Besides, positive association with pertussis was observed in subjects with a history of steroid treatment (OR=5.67) and those with a recent contact with a lasting cough (OR=4.12). When using a case-control study to evaluate the effectiveness of vaccines, particularly those for uncommon infectious diseases such as pertussis, the use of friend-controls may be optimal due to the fact that they shared a similar experience for exposure to the pathogen as the cases. In addition, to assess vaccine effectiveness as accurately as possible, the effects of confounding should be adequately controlled with a matching or analysis technique. Copyright © 2017 The Author(s). Published by Elsevier Ltd.. All rights reserved.

  14. Histomorphometric characteristics of immune cells in small intestine of pigs perorally immunized with vaccine candidate F18ac+ nonenterotoxigenic E. coli strain

    Directory of Open Access Journals (Sweden)

    I. Valpotic

    2009-12-01

    Full Text Available Colidiarrhea and colienterotoxemia caused by F4+ and/or F18+ enterotoxigenic E. coli (ETEC strains are the most prevalent infections of suckling and weaned pigs. Here we tested the immunogenicity and protective effectiveness of attenuated F18ac+ non-ETEC vaccine candidate strain against challenge infection with F4ac+ ETEC strain by quantitative phenotypic analysis of small intestinal leukocyte subsets in weaned pigs. We also evaluated levamisole as an immune response modifier (IRM and its adjuvanticity when given in the combination with the experimental vaccine. The pigs were parenterally immunized with either levamisole (at days -2, -1 and 0 or with levamisole and perorally given F18ac+ non-ETEC strain (at day 0, and challenged with F4ac+ ETEC strain 7 days later. At day 13 the pigs were euthanatized and sampled for immunohistological/histomorphometrical analyses. Lymphoid CD3+, CD45RA+, CD45RC+, CD21+, IgA+ and myeloid SWC3+ cell subsets were identified in jejunal and ileal epithelium, lamina propria and Peyer’s patches using the avidin-biotin complex method, and their numbers were determined by computer-assisted histomorphometry. Quantitative immunophenotypic analyses showed that levamisole treated pigs had highly increased numbers of jejunal CD3+, CD45RC+ and SWC3+ cells (p<0.05 as compared to those recorded in nontreated control pigs. In the ileum of these pigs we have recorded that only CD21+ cells were significantly increased (p<0.01. The pigs that were treated with levamisole adjuvanted experimental vaccine had significantly increased numbers of all tested cell subsets in both segments of the small intestine. It was concluded that levamisole adjuvanted F18ac+ non-ETEC vaccine was a requirement for the elicitation of protective gut immunity in this model; nonspecific immunization with levamisole was less effective, but confirmed its potential as an IRM.

  15. Substitutions at residues 300 and 389 of the VP2 capsid protein serve as the minimal determinant of attenuation for canine parvovirus vaccine strain 9985-46.

    Science.gov (United States)

    Sehata, Go; Sato, Hiroaki; Yamanaka, Morimasa; Takahashi, Takuo; Kainuma, Risa; Igarashi, Tatsuhiko; Oshima, Sho; Noro, Taichi; Oishi, Eiji

    2017-11-01

    Identifying molecular determinants of virulence attenuation in live attenuated canine parvovirus (CPV) vaccines is important for assuring their safety. To this end, we identified mutations in the attenuated CPV 9985-46 vaccine strain that arose during serial passage in Crandell-Rees feline kidney cells by comparison with the wild-type counterpart, as well as minimal determinants of the loss of virulence. Four amino acid substitutions (N93K, G300V, T389N and V562L) in VP2 of strain 9985-46 significantly restricted infection in canine A72 cells. Using an infectious molecular clone system, we constructed isogenic CPVs of the parental virulent 9985 strain carrying single or double mutations. We observed that only a single amino acid substitution in VP2, G300V or T389N, attenuated the virulent parental virus. Combinations of these mutations further attenuated CPV to a level comparable to that of 9985-46. Strains with G300V/T389N substitutions did not induce clinical symptoms in experimentally infected pups, and their ability to infect canine cells was highly restricted. We found that another G300V/V562L double mutation decreased affinity of the virus for canine cells, although its pathogenicity to dogs was maintained. These results indicate that mutation of residue 300, which plays a critical role in host tropism, is not sufficient for viral attenuation in vivo, and that attenuation of 9985-46 strain is defined by at least two mutations in residues 300 and 389 of the VP2 capsid protein. This finding is relevant for quality control of the vaccine and provides insight into the rational design of second-generation live attenuated vaccine candidates.

  16. Selection of oleuropein-degrading lactic acid bacteria strains isolated from fermenting Moroccan green olives

    Energy Technology Data Exchange (ETDEWEB)

    Ghabbour, N.; Lamzira, Z.; Thonart, P.; Cidalia, P.; Markaouid, M.; Asehraoua, A.

    2011-07-01

    A total of 177 strains of lactic acid bacteria (LAB) were isolated from early-stage Moroccan Picholine green olive fermentation, including Lactobacillus plantarum (44.63%), Lactobacillus pentosus (25.99%), Lactobacillus brevis (9.61%) and Pediococcus pentosaceus (19.77%). All the isolates were screened for their tolerance to olive leaf extract and oleuropein. Most of the isolates (85.3%) were found able to degrade oleuropein, when evaluated by either oleuropein or 5-Bromo-4-chloro-3-indolyl {beta}-D-glucuronide (X-Gluc) as substrates. The biodegradation capacity of the selected strains of each species was confirmed by HPLC analysis. (Author).

  17. Development of a rapid screening protocol for selection of strains resistant to spray drying and storage in dry powder.

    Science.gov (United States)

    Reimann, S; Grattepanche, F; Baggenstos, C; Rezzonico, E; Berger, B; Arigoni, F; Lacroix, C

    2010-06-01

    An efficient screening method for selection of Bifidobacterium longum strains resistant to spray drying and storage was developed based on randomly amplified polymorphic DNA (RAPD) for identification of the best survivors in mixed strains bacterial preparations. Three different primers were used to generate RAPD profiles of 22 B. longum strains. All strains were distinguished according to their RAPD profiles except for the strain NCC2705 and its H(2)O(2) resistant derivative variant. The 22 strains were grouped in 3 batches of 7, 7 and 8 strains and subjected to spray drying and storage at 30 and 37 °C under anaerobic conditions. Batch survival rates after spray drying reached 17.1±4.4%. Strains showing the highest prevalence and/or resistance to storage at 37 °C were selected from individual batches for subsequent spray drying and storage testing. After 67 days of storage, NCC572 was identified as the dominant strain in powder. The stability of strain NCC572 was confirmed by performing single spray drying and storage tests. Out of 22 B. longum strains, a robust strain was identified by combining RAPD with a simultaneous screening test for survival under spray drying and storage. The method allowed a fast screening of B. longum strains in mixture for resistance to spray drying and storage compared to traditional screening procedures carried out with individual strains, in the same conditions. This approach could be applied to other stress conditions.

  18. One-step multiplex real-time RT-PCR assay for detecting and genotyping wild-type group A rotavirus strains and vaccine strains (Rotarix® and RotaTeq®) in stool samples

    Science.gov (United States)

    Mijatovic-Rustempasic, Slavica; Esona, Mathew D.; Tam, Ka Ian; Quaye, Osbourne; Bowen, Michael D.

    2016-01-01

    Background. Group A rotavirus (RVA) infection is the major cause of acute gastroenteritis (AGE) in young children worldwide. Introduction of two live-attenuated rotavirus vaccines, RotaTeq® and Rotarix®, has dramatically reduced RVA associated AGE and mortality in developed as well as in many developing countries. High-throughput methods are needed to genotype rotavirus wild-type strains and to identify vaccine strains in stool samples. Quantitative RT-PCR assays (qRT-PCR) offer several advantages including increased sensitivity, higher throughput, and faster turnaround time. Methods. In this study, a one-step multiplex qRT-PCR assay was developed to detect and genotype wild-type strains and vaccine (Rotarix® and RotaTeq®) rotavirus strains along with an internal processing control (Xeno or MS2 RNA). Real-time RT-PCR assays were designed for VP7 (G1, G2, G3, G4, G9, G12) and VP4 (P[4], P[6] and P[8]) genotypes. The multiplex qRT-PCR assay also included previously published NSP3 qRT-PCR for rotavirus detection and Rotarix® NSP2 and RotaTeq® VP6 qRT-PCRs for detection of Rotarix® and RotaTeq® vaccine strains respectively. The multiplex qRT-PCR assay was validated using 853 sequence confirmed stool samples and 24 lab cultured strains of different rotavirus genotypes. By using thermostable rTth polymerase enzyme, dsRNA denaturation, reverse transcription (RT) and amplification (PCR) steps were performed in single tube by uninterrupted thermocycling profile to reduce chances of sample cross contamination and for rapid generation of results. For quantification, standard curves were generated using dsRNA transcripts derived from RVA gene segments. Results. The VP7 qRT-PCRs exhibited 98.8–100% sensitivity, 99.7–100% specificity, 85–95% efficiency and a limit of detection of 4–60 copies per singleplex reaction. The VP7 qRT-PCRs exhibited 81–92% efficiency and limit of detection of 150–600 copies in multiplex reactions. The VP4 qRT-PCRs exhibited 98.8

  19. Strengthening the influenza vaccine virus selection and development process: Report of the 3rd WHO Informal Consultation for Improving Influenza Vaccine Virus Selection held at WHO headquarters, Geneva, Switzerland, 1-3 April 2014.

    Science.gov (United States)

    Ampofo, William K; Azziz-Baumgartner, Eduardo; Bashir, Uzma; Cox, Nancy J; Fasce, Rodrigo; Giovanni, Maria; Grohmann, Gary; Huang, Sue; Katz, Jackie; Mironenko, Alla; Mokhtari-Azad, Talat; Sasono, Pretty Multihartina; Rahman, Mahmudur; Sawanpanyalert, Pathom; Siqueira, Marilda; Waddell, Anthony L; Waiboci, Lillian; Wood, John; Zhang, Wenqing; Ziegler, Thedi

    2015-08-26

    Despite long-recognized challenges and constraints associated with their updating and manufacture, influenza vaccines remain at the heart of public health preparedness and response efforts against both seasonal and potentially pandemic influenza viruses. Globally coordinated virological and epidemiological surveillance is the foundation of the influenza vaccine virus selection and development process. Although national influenza surveillance and reporting capabilities are being strengthened and expanded, sustaining and building upon recent gains has become a major challenge. Strengthening the vaccine virus selection process additionally requires the continuation of initiatives to improve the timeliness and representativeness of influenza viruses shared by countries for detailed analysis by the WHO Global Influenza Surveillance and Response System (GISRS). Efforts are also continuing at the national, regional, and global levels to better understand the dynamics of influenza transmission in both temperate and tropical regions. Improved understanding of the degree of influenza seasonality in tropical countries of the world should allow for the strengthening of national vaccination policies and use of the most appropriate available vaccines. There remain a number of limitations and difficulties associated with the use of HAI assays for the antigenic characterization and selection of influenza vaccine viruses by WHOCCs. Current approaches to improving the situation include the more-optimal use of HAI and other assays; improved understanding of the data produced by neutralization assays; and increased standardization of serological testing methods. A number of new technologies and associated tools have the potential to revolutionize influenza surveillance and response activities. These include the increasingly routine use of whole genome next-generation sequencing and other high-throughput approaches. Such approaches could not only become key elements in outbreak

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

    Science.gov (United States)

    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...

  1. Screening of Probiotic Activities of Forty-Seven Strains of Lactobacillus spp. by In Vitro Techniques and Evaluation of the Colonization Ability of Five Selected Strains in Humans

    OpenAIRE

    Jacobsen, C. N.; Rosenfeldt Nielsen, V.; Hayford, A. E.; Møller, P. L.; Michaelsen, K. F.; Pærregaard, A.; Sandström, B.; Tvede, M.; Jakobsen, M.

    1999-01-01

    The probiotic potential of 47 selected strains of Lactobacillus spp. was investigated. The strains were examined for resistance to pH 2.5 and 0.3% oxgall, adhesion to Caco-2 cells, and antimicrobial activities against enteric pathogenic bacteria in model systems. From the results obtained in vitro, five strains, Lactobacillus rhamnosus 19070-2, L. reuteri DSM 12246, L. rhamnosus LGG, L. delbrueckii subsp. lactis CHCC 2329, and L. casei subsp. alactus CHCC 3137, were selected for in vivo studi...

  2. Selection of bacteriocin producer strains of lactic acid bacteria from a dairy environment.

    Science.gov (United States)

    Lasagno, M; Beoleito, V; Sesma, F; Raya, R; Font de Valdez, G; Eraso, A

    2002-01-01

    Two strains showing bacteriocin production were selected from a total of 206 lactic acid bacteria isolated from samples of milk, milk serum, whey and homemade cheeses in Southern Cordoba, Argentina. This property was detected by means of well diffusion assays. The strains were identified as Enterococcus hirae and Enterococcus durans. The protein nature of those substances was proved by showing their sensitivity to type IV and XXV proteases, papaine, trypsin, pepsin and K proteinase. The bacteriocins inhibited the growth of Listeria monocytogenes, Bacillus cereus, Clostridium perfringes and two strains of Staphylococcus aureus, an A-enterotoxin and a B-enterotoxin producers. All of these bacteria are common pathogens usually associated with food borne diseases (ETA). These lactic acid bacteria or their bacteriocins could be suitable candidates for food preservation and specially useful in the our regional dairy industry.

  3. Pulmonary immunity and durable protection induced by the ID93/GLA-SE vaccine candidate against the hyper-virulent Korean Beijing Mycobacterium tuberculosis strain K.

    Science.gov (United States)

    Cha, Seung Bin; Kim, Woo Sik; Kim, Jong-Seok; Kim, Hongmin; Kwon, Kee Woong; Han, Seung Jung; Cho, Sang-Nae; Coler, Rhea N; Reed, Steven G; Shin, Sung Jae

    2016-04-27

    The majority of tuberculosis (TB) vaccine candidates advanced to clinical trials have been evaluated preclinically using laboratory-adapted strains. However, it has been proposed that challenge with clinical isolates in preclinical vaccine testing could provide further and more practical validation. Here, we tested the ID93/GLA-SE TB vaccine candidate against the clinical Mycobacterium tuberculosis (Mtb) strain K (Mtb K) belonging to the Beijing family, the most prevalent Mtb strain in South Korea. Mice immunized with ID93/GLA-SE exhibited a significant reduction in bacteria and reduced lung inflammation against Mtb K when compared to non-immunized controls. In addition, we analyzed the immune responses in the lungs of ID93/GLA-SE-immunized mice, and showed that ID93/GLA-SE was able to elicit sustained Th1-biased immune responses including antigen-specific multifunctional CD4(+) T cell co-producing IFN-γ, TNF-α, and IL-2 as well as a high magnitude of IFN-γ response for up to 10 weeks post-challenge. Notably, further investigation of T cell subsets in the lung following challenge showed remarkable generation of CD8(+) central memory T cells by ID93/GLA-SE-immunization. Our findings showed that ID93/GLA-SE vaccine confers a high level of robust protection against the hypervirulent Mtb Beijing infection which was characterized by pulmonary Th1-polarized T-cell immune responses. These findings may also provide relevant information for potential utility of this vaccine candidate in East-Asian countries where the Beijing genotype is highly prevalent. Copyright © 2016 Elsevier Ltd. All rights reserved.

  4. Emergence of canine distemper virus strains with two amino acid substitutions in the haemagglutinin protein, detected from vaccinated carnivores in North-Eastern China in 2012-2013.

    Science.gov (United States)

    Zhao, Jianjun; Zhang, Hailing; Bai, Xue; Martella, Vito; Hu, Bo; Sun, Yangang; Zhu, Chunsheng; Zhang, Lei; Liu, Hao; Xu, Shujuan; Shao, Xiqun; Wu, Wei; Yan, Xijun

    2014-04-01

    A total of 16 strains of canine distemper virus (CDV) were detected from vaccinated minks, foxes, and raccoon dogs in four provinces in North-Eastern China between the end of 2011 and 2013. Upon sequence analysis of the haemagglutinin gene and comparison with wild-type CDV from different species in the same geographical areas, two non-synonymous single nucleotide polymorphisms were identified in 10 CDV strains, which led to amino acid changes at positions 542 (isoleucine to asparagine) and 549 (tyrosine to histidine) of the haemagglutinin protein coding sequence. The change at residue 542 generated a potentially novel N-glycosylation site. Masking of antigenic epitopes by sugar moieties might represent a mechanism for evasion of virus neutralising antibodies and reduced protection by vaccination. Copyright © 2014 Elsevier Ltd. All rights reserved.

  5. 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.

    Science.gov (United States)

    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.

  6. A minor groove binder probe real-time PCR assay for discrimination between type 2-based vaccines and field strains of canine parvovirus.

    Science.gov (United States)

    Decaro, Nicola; Elia, Gabriella; Desario, Costantina; Roperto, Sante; Martella, Vito; Campolo, Marco; Lorusso, Alessio; Cavalli, Alessandra; Buonavoglia, Canio

    2006-09-01

    A minor groove binder (MGB) probe assay was developed to discriminate between type 2-based vaccines and field strains of canine parvovirus (CPV). Considering that most of the CPV vaccines contain the old type 2, no longer circulating in canine population, two MGB probes specific for CPV-2 and the antigenic variants (types 2a, 2b and 2c), respectively, were labeled with different fluorophores. The MGB probe assay was able to discriminate correctly between the old type and the variants, with a detection limit of 10(1) DNA copies and a good reproducibility. Quantitation of the viral DNA loads was accurate, as demonstrated by comparing the CPV DNA titres to those calculated by means of the TaqMan assay recognising all CPV types. This assay will ensure resolution of most diagnostic problems in dogs showing CPV disease shortly after CPV vaccination, although it does not discriminate between field strains and type 2b-based vaccines, recently licensed to market in some countries.

  7. Thermostability of reconstituted newcastle disease virus strains at 36 ...

    African Journals Online (AJOL)

    Haemagglutination (HA) test was employed to determine the stability of HA titers of reconstituted form of Hitchner – B1 (B1), LaSota (L) and Komarov (K) strains of Newcastle Disease Vaccine (NDV) at 360c. The temperature treatment method was through incubation (in water bath) of the reconstituted vaccines at selected ...

  8. The Ondersteport Canine distemper virus strain and measles ...

    African Journals Online (AJOL)

    Three groups of dogs aged three months each were used in an experiment to assess efficacy of imported Canine distemper vaccine (Ondersteport strain) and measles vaccine in protecting Nigerian dogs against local isolates of Canine distemper virus. Each group consisted of four randomly selected puppies. One group ...

  9. Molecular and biological characterization of the 5 human-bovine rotavirus (WC3)-based reassortant strains of the pentavalent rotavirus vaccine, RotaTeq (registered)

    International Nuclear Information System (INIS)

    Matthijnssens, Jelle; Joelsson, Daniel B.; Warakomski, Donald J.; Zhou, Tingyi; Mathis, Pamela K.; Maanen, Marc-Henri van; Ranheim, Todd S.; Ciarlet, Max

    2010-01-01

    RotaTeq (registered) is a pentavalent rotavirus vaccine that contains five human-bovine reassortant strains (designated G1, G2, G3, G4, and P1) on the backbone of the naturally attenuated tissue culture-adapted parental bovine rotavirus (BRV) strain WC3. The viral genomes of each of the reassortant strains were completely sequenced and compared pairwise and phylogenetically among each other and to human rotavirus (HRV) and BRV reference strains. Reassortants G1, G2, G3, and G4 contained the VP7 gene from their corresponding HRV parent strains, while reassortants G1 and G2 also contained the VP3 gene (genotype M1) from the HRV parent strain. The P1 reassortant contained the VP4 gene from the HRV parent strain and all the other gene segments from the BRV WC3 strain. The human VP7s had a high level of overall amino acid identity (G1: 95-99%, G2: 94-99% G3: 96-100%, G4: 93-99%) when compared to those of representative rotavirus strains of their corresponding G serotypes. The VP4 of the P1 reassortant had a high identity (92-97%) with those of serotype P1A[8] HRV reference strains, while the BRV VP7 showed identities ranging from 91% to 94% to those of serotype G6 HRV strains. Sequence analyses of the BRV or HRV genes confirmed that the fundamental structure of the proteins in the vaccine was similar to those of the HRV and BRV references strains. Sequences analyses showed that RotaTeq (registered) exhibited a high degree of genetic stability as no mutations were identified in the material of each reassortant, which undergoes two rounds of replication cycles in cell culture during the manufacturing process, when compared to the final material used to fill the dosing tubes. The infectivity of each of the reassortant strains of RotaTeq (registered) , like HRV strains, did not require the presence of sialic acid residues on the cell surface. The molecular and biologic characterization of RotaTeq (registered) adds to the significant body of clinical data supporting the

  10. Genetic diversity and symbiotic effectiveness of Bradyrhizobium strains nodulating selected annual grain legumes growing in Ethiopia.

    Science.gov (United States)

    Degefu, Tulu; Wolde-Meskel, Endalkachew; Rasche, Frank

    2018-01-01

    Vigna unguiculata, Vigna radiata and Arachis hypogaea growing in Ethiopia are nodulated by a genetically diverse group of Bradyrhizobium strains. To determine the genetic identity and symbiotic effectiveness of these bacteria, a collection of 36 test strains originating from the root nodules of the three hosts was investigated using multilocus sequence analyses (MLSA) of core genes including 16S rRNA, recA, glnII, gyrB, atpD and dnaK. Sequence analysis of nodA and nifH genes along with tests for symbiotic effectiveness using δ 15 N analysis were also carried out. The phylogenetic trees derived from the MLSA grouped most test strains into four well-supported distinct positions designated as genospecies I-IV. The maximum likelihood (ML) tree that was constructed based on the nodA gene sequences separated the entire test strains into two lineages, where the majority of the test strains were clustered on one of a well-supported large branch that comprise Bradyrhizobium species from the tropics. This clearly suggested the monophyletic origin of the nodA genes within the bradyrhizobia of tropical origin. The δ 15 N-based symbiotic effectiveness test of seven selected strains revealed that strains GN100 (δ 15 N=0.73) and GN102 (δ 15 N=0.79) were highly effective nitrogen fixers when inoculated to cowpea, thus can be considered as inoculants in cowpea production. It was concluded that Ethiopian soils are a hotspot for rhizobial diversity. This calls for further research to unravel as yet unknown bradyrhizobia nodulating legume host species growing in the country. In this respect, prospective research should also address the mechanisms of symbiotic specificity that could lead to high nitrogen fixation in target legumes.

  11. Swine influenza virus vaccines: to change or not to change-that's the question.

    Science.gov (United States)

    Van Reeth, Kristien; Ma, Wenjun

    2013-01-01

    Commercial vaccines currently available against swine influenza virus (SIV) are inactivated, adjuvanted, whole virus vaccines, based on H1N1 and/or H3N2 and/or H1N2 SIVs. In keeping with the antigenic and genetic differences between SIVs circulating in Europe and the US, the vaccines for each region are produced locally and contain different strains. Even within a continent, there is no standardization of vaccine strains, and the antigen mass and adjuvants can also differ between different commercial products. Recombinant protein vaccines against SIV, vector, and DNA vaccines, and vaccines attenuated by reverse genetics have been tested in experimental studies, but they have not yet reached the market. In this review, we aim to present a critical analysis of the performance of commercial inactivated and novel generation SIV vaccines in experimental vaccination challenge studies in pigs. We pay special attention to the differences between commercial SIV vaccines and vaccination attitudes in Europe and in North America, to the issue of vaccine strain selection and changes, and to the potential advantages of novel generation vaccines over the traditional killed SIV vaccines.

  12. Screening and selection of wild strains for L-arabinose isomerase production

    Directory of Open Access Journals (Sweden)

    R. M. Manzo

    2013-12-01

    Full Text Available The majority of L-arabinose isomerases have been isolated by recombinant techniques, but this methodology implies a reduced technological application. For this reason, 29 bacterial strains, some of them previously characterized as L-arabinose isomerase producers, were assayed as L-arabinose fermenting strains by employing conveniently designed culture media with 0.5% (w/v L-arabinose as main carbon source. From all evaluated bacterial strains, Enterococcus faecium DBFIQ ID: E36, Enterococcus faecium DBFIQ ID: ETW4 and Pediococcus acidilactici ATCC ID: 8042 were, in this order, the best L-arabinose fermenting strains. Afterwards, to assay L-arabinose metabolization and L-arabinose isomerase activity, cell-free extract and saline precipitated cell-free extract of the three bacterial cultures were obtained and the production of ketoses was determined by the cysteine carbazole sulfuric acid method. Results showed that the greater the L-arabinose metabolization ability, the higher the enzymatic activity achieved, so Enterococcus faecium DBFIQ ID: E36 was selected to continue with production, purification and characterization studies. This work thus describes a simple microbiological method for the selection of L-arabinose fermenting bacteria for the potential production of the enzyme L-arabinose isomerase.

  13. Evaluation of a LaSota strain-based recombinant Newcastle disease virus (NDV) expressing the glycoprotein (G) of avian metapneumovirus (aMPV) subgroup A or B as a bivalent vaccine in turkeys

    Science.gov (United States)

    To develop a bivalent vaccine candidate, a LaSota strain-based recombinant Newcastle disease virus (NDV) clone expressing the glycoprotein (G) of avian metapneumovirus (aMPV) subgroup A or B was generated using reverse genetics. Vaccination of turkeys with the NDV/aMPV-A G or NDV/aMPV-B G recombinan...

  14. Evolution of type 2 vaccine derived poliovirus lineages. Evidence for codon-specific positive selection at three distinct locations on capsid wall.

    Directory of Open Access Journals (Sweden)

    Tapani Hovi

    Full Text Available Partial sequences of 110 type 2 poliovirus strains isolated from sewage in Slovakia in 2003-2005, and most probably originating from a single dose of oral poliovirus vaccine, were subjected to a detailed genetic analysis. Evolutionary patterns of these vaccine derived poliovirus strains (SVK-aVDPV2 were compared to those of type 1 and type 3 wild poliovirus (WPV lineages considered to have a single seed strain origin, respectively. The 102 unique SVK-aVDPV VP1 sequences were monophyletic differing from that of the most likely parental poliovirus type 2/Sabin (PV2 Sabin by 12.5-15.6%. Judging from this difference and from the rate of accumulation of synonymous transversions during the 22 month observation period, the relevant oral poliovirus vaccine dose had been administered to an unknown recipient more than 12 years earlier. The patterns of nucleotide substitution during the observation period differed from those found in the studied lineages of WPV1 or 3, including a lower transition/transversion (Ts/Tv bias and strikingly lower Ts/Tv rate ratios at the 2(nd codon position for both purines and pyrimidines. A relatively low preference of transitions at the 2(nd codon position was also found in the large set of VP1 sequences of Nigerian circulating (cVDPV2, as well as in the smaller sets from the Hispaniola cVDPV1 and Egypt cVDPV2 outbreaks, and among aVDPV1and aVDPV2 strains recently isolated from sewage in Finland. Codon-wise analysis of synonymous versus non-synonymous substitution rates in the VP1 sequences suggested that in five codons, those coding for amino acids at sites 24, 144, 147, 221 and 222, there may have been positive selection during the observation period. We conclude that pattern of poliovirus VP1 evolution in prolonged infection may differ from that found in WPV epidemics. Further studies on sufficiently large independent datasets are needed to confirm this suggestion and to reveal its potential significance.

  15. 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.

    Directory of Open Access Journals (Sweden)

    Hai Jiang

    Full Text Available 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.

  16. Succession of Selected Strains of Acetobacter pasteurianus and Other Acetic Acid Bacteria in Traditional Balsamic Vinegar

    OpenAIRE

    Gullo, M.; De Vero, L.; Giudici, P.

    2009-01-01

    The application of a selected Acetobacter pasteurianus strain for traditional balsamic vinegar production was assessed. Genomic DNA was extracted from biofilms after enrichment cultures on GYC medium (10% glucose, 1.0% yeast extract, 2.0% calcium carbonate) and used for PCR/denaturing gradient gel electrophoresis, 16S rRNA gene sequencing, and enterobacterial repetitive intergenic consensus/PCR sequencing. Results suggested that double-culture fermentation is suitable for traditional balsamic...

  17. Residual strain in the Nb-H system measured by selected area diffraction (SAD)

    International Nuclear Information System (INIS)

    Bulhoes, I.A.M.; Akune, K.; Pinatti, Dyonisio G.

    1981-07-01

    Various specimens of Nb were annealed in vacuum of 10 -3 torr for four hours at 1770 0 K. These speciments were doped with hydrogen up to 1000 ppm by weight and then were analyzed selected area diffraction. The line resolution of the electron channelling pattern was meassured for the specimens with different hydrogen content. These measurements, combined with the measurement of density, permitted one to estimate the residual strain caused by hydrogen. (Author) [pt

  18. Intramuscular Immunization of Mice with the Live-Attenuated Herpes Simplex Virus 1 Vaccine Strain VC2 Expressing Equine Herpesvirus 1 (EHV-1) Glycoprotein D Generates Anti-EHV-1 Immune Responses in Mice.

    Science.gov (United States)

    Liu, Shiliang A; Stanfield, Brent A; Chouljenko, Vladimir N; Naidu, Shan; Langohr, Ingeborg; Del Piero, Fabio; Ferracone, Jacqueline; Roy, Alma A; Kousoulas, Konstantin G

    2017-06-15

    Vaccination remains the best option to combat equine herpesvirus 1 (EHV-1) infection, and several different strategies of vaccination have been investigated and developed over the past few decades. Herein, we report that the live-attenuated herpes simplex virus 1 (HSV-1) VC2 vaccine strain, which has been shown to be unable to enter into neurons and establish latency in mice, can be utilized as a vector for the heterologous expression of EHV-1 glycoprotein D (gD) and that the intramuscular immunization of mice results in strong antiviral humoral and cellular immune responses. The VC2-EHV-1-gD recombinant virus was constructed by inserting an EHV-1 gD expression cassette under the control of the cytomegalovirus immediate early promoter into the VC2 vector in place of the HSV-1 thymidine kinase (UL23) gene. The vaccines were introduced into mice through intramuscular injection. Vaccination with both the VC2-EHV-1-gD vaccine and the commercially available vaccine Vetera EHV XP 1/4 (Vetera; Boehringer Ingelheim Vetmedica) resulted in the production of neutralizing antibodies, the levels of which were significantly higher in comparison to those in VC2- and mock-vaccinated animals ( P < 0.01 or P < 0.001). Analysis of EHV-1-reactive IgG subtypes demonstrated that vaccination with the VC2-EHV-1-gD vaccine stimulated robust IgG1 and IgG2a antibodies after three vaccinations ( P < 0.001). Interestingly, Vetera-vaccinated mice produced significantly higher levels of IgM than mice in the other groups before and after challenge ( P < 0.01 or P < 0.05). Vaccination with VC2-EHV-1-gD stimulated strong cellular immune responses, characterized by the upregulation of both interferon- and tumor necrosis factor-positive CD4 + T cells and CD8 + T cells. Overall, the data suggest that the HSV-1 VC2 vaccine strain may be used as a viral vector for the vaccination of horses as well as, potentially, for the vaccination of other economically important animals. IMPORTANCE A novel virus

  19. Environmental carbonate chemistry selects for phenotype of recently isolated strains of Emiliania huxleyi

    Science.gov (United States)

    Rickaby, Rosalind E. M.; Hermoso, Michaël; Lee, Renee B. Y.; Rae, Benjamin D.; Heureux, Ana M. C.; Balestreri, Cecilia; Chakravarti, Leela; Schroeder, Declan C.; Brownlee, Colin

    2016-05-01

    Coccolithophorid algae, particularly Emiliania huxleyi, are prolific biomineralisers that, under many conditions, dominate communities of marine eukaryotic plankton. Their ability to photosynthesise and form calcified scales (coccoliths) has placed them in a unique position in the global carbon cycle. Contrasting reports have been made with regards to the response of E. huxleyi to ocean acidification. Therefore, there is a pressing need to further determine the fate of this key organism in a rising CO2 world. In this paper, we investigate the phenotype of newly isolated, genetically diverse, strains of E. huxleyi from UK Ocean Acidification Research Programme (UKOA) cruises around the British Isles, the Arctic, and the Southern Ocean. We find a continuum of diversity amongst the physiological and photosynthetic parameters of different strains of E. huxleyi morphotype A under uniform, ambient conditions imposed in the laboratory. This physiology is best explained by adaptation to carbonate chemistry in the former habitat rather than being prescribed by genetic fingerprints such as the coccolithophore morphology motif (CMM). To a first order, the photosynthetic capacity of each strain is a function of both aqueous CO2 availability, and calcification rate, suggestive of a link between carbon concentrating ability and calcification. The calcification rate of each strain is related linearly to the natural environmental [CO32-] at the site of isolation, but a few exceptional strains display low calcification rates at the highest [CO32-] when calcification is limited by low CO2 availability and/or a lack of a carbon concentrating mechanism. We present O2-electrode measurements alongside coccolith oxygen isotopic composition and the uronic acid content (UAC) of the coccolith associated polysaccharide (CAP), that act as indirect tools to show the differing carbon concentrating ability of the strains. The environmental selection revealed amongst our recently isolated strain

  20. Systematic documentation of new vaccine introduction in selected countries of the Latin American Region.

    Science.gov (United States)

    de Oliveira, Lúcia H; Toscano, Cristiana M; Sanwogou, N Jennifer; Ruiz-Matus, Cuauhtémoc; Tambini, Gina; Roses-Periago, Mirta; Andrus, Jon K

    2013-07-02

    Countries in Latin America were among the first developing countries to introduce new vaccines, particularly rotavirus (RV) and pneumococcal conjugate vaccines (PCVs), into their national immunization schedules. Experiences and lessons learned from these countries are valuable to donors, immunization partners, and policy makers in other countries wishing to make informed decisions on vaccine introduction. In order to enhance knowledge and promote understanding of the process of new vaccine introduction in the Latin American Region, with particular focus on RV and PCV, we conducted a systematic qualitative assessment. We evaluated the decision-making process, documented the structure in place, and reviewed key factors pertaining to new vaccine introduction. These include country morbidity and mortality data available prior to vaccine introduction, funding sources and mechanisms for vaccine introduction, challenges of implementation, and assessment of vaccine impact. From March 2010 to April 2011, we evaluated a subset of countries that had introduced RV and/or PCV in the past five years through interviews with key informants at the country level and through a systematic review of published data, gray literature, official technical documents, and country-specific health indicators. Countries evaluated were Bolivia, Brazil, Nicaragua, Peru, and Venezuela. In all countries, the potential of new vaccines to reduce mortality, as established by Millennium Development Goal 4, was an important consideration leading to vaccine introduction. Several factors-the availability of funds, the existence of sufficient evidence for vaccine introduction, and the feasibility of sustainable financing-were identified as crucial components of the decision-making process in the countries evaluated. The decision making process regarding new vaccine introduction in the countries evaluated does not follow a systematic approach. Nonetheless, existing evidence on efficacy, potential impact, and

  1. Vaccine breaks: Outbreaks of myxomatosis on Spanish commercial rabbit farms.

    Science.gov (United States)

    Dalton, K P; Nicieza, I; de Llano, D; Gullón, J; Inza, M; Petralanda, M; Arroita, Z; Parra, F

    2015-08-05

    Despite the success of vaccination against myxoma virus, myxomatosis remains a problem on rabbit farms throughout Spain and Europe. In this study we set out to evaluate possible causes of myxoma virus (MYXV) vaccine failures addressing key issues with regard to pathogen, vaccine and vaccination strategies. This was done by genetically characterising MYXV field isolates from farm outbreaks, selecting a representative strain for which to assay its virulence and measuring the protective capability of a commercial vaccine against this strain. Finally, we compare methods (route) of vaccine administration under farm conditions and evaluate immune response in vaccinated rabbits. The data presented here show that the vaccine tested is capable of eliciting protection in rabbits that show high levels of seroconversion. However, the number of animals failing to seroconvert following subcutaneous vaccination may leave a large number of rabbits unprotected following vaccine administration. Successful vaccination requires the strict implication of workable, planned, on farm programs. Following this, analysis to confirm seroconversion rates may be advisable. Factors such as the wild rabbit reservoir, control of biting insects and good hygienic practices must be taken into consideration to prevent vaccine failures from occurring. Copyright © 2015 Elsevier B.V. All rights reserved.

  2. Patterns of survival and volatile metabolites of selected Lactobacillus strains during long-term incubation in milk.

    Science.gov (United States)

    Łaniewska-Trokenheim, Łucja; Olszewska, Magdalena; Miks-Krajnik, Marta; Zadernowska, Anna

    2010-08-01

    The focus of this study was to monitor the survival of populations and the volatile compound profiles of selected Lactobacillus strains during long-term incubation in milk. The enumeration of cells was determined by both the Direct Epifluorescent Filter Technique using carboxyfluorescein diacetate (CFDA) staining and the plate method. Volatile compounds were analysed by the gas-chromatography technique. All strains exhibited good survival in cultured milks, but Lactobacillus crispatus L800 was the only strain with comparable growth and viability in milk, assessed by plate and epifluorescence methods. The significant differences in cell numbers between plate and microscopic counts were obtained for L. acidophilus strains. The investigated strains exhibited different metabolic profiles. Depending on the strain used, 3 to 8 compounds were produced. The strains produced significantly higher concentrations of acetic acid, compared to other volatiles. Lactobacillus strains differed from one another in number and contents of the volatile compounds.

  3. Microarray-based comparative genomic profiling of reference strains and selected Canadian field isolates of Actinobacillus pleuropneumoniae

    Directory of Open Access Journals (Sweden)

    MacInnes Janet I

    2009-02-01

    Full Text Available Abstract Background Actinobacillus pleuropneumoniae, the causative agent of porcine pleuropneumonia, is a highly contagious respiratory pathogen that causes severe losses to the swine industry worldwide. Current commercially-available vaccines are of limited value because they do not induce cross-serovar immunity and do not prevent development of the carrier state. Microarray-based comparative genomic hybridizations (M-CGH were used to estimate whole genomic diversity of representative Actinobacillus pleuropneumoniae strains. Our goal was to identify conserved genes, especially those predicted to encode outer membrane proteins and lipoproteins because of their potential for the development of more effective vaccines. Results Using hierarchical clustering, our M-CGH results showed that the majority of the genes in the genome of the serovar 5 A. pleuropneumoniae L20 strain were conserved in the reference strains of all 15 serovars and in representative field isolates. Fifty-eight conserved genes predicted to encode for outer membrane proteins or lipoproteins were identified. As well, there were several clusters of diverged or absent genes including those associated with capsule biosynthesis, toxin production as well as genes typically associated with mobile elements. Conclusion Although A. pleuropneumoniae strains are essentially clonal, M-CGH analysis of the reference strains of the fifteen serovars and representative field isolates revealed several classes of genes that were divergent or absent. Not surprisingly, these included genes associated with capsule biosynthesis as the capsule is associated with sero-specificity. Several of the conserved genes were identified as candidates for vaccine development, and we conclude that M-CGH is a valuable tool for reverse vaccinology.

  4. Research of angelica sinensis (Oliv) diels new strain DGA2000-02 selection

    International Nuclear Information System (INIS)

    Xie Hongmei; Li Wenjian; Hao Jifang; Liu Jing; Liu Xiaorui; Jing Yanming; Shang Hushan; Liu Rongqing; He Baogang; Wang Chunming; Zhang Guoli; Chen Shuzhen

    2008-01-01

    Angelica sinensis(Oliv)Diets new strain DGA2000-02 was selected successfully by Institute of Modern Physics, Chinese Academy of Sciences, Dryland Farming Research and Extension Center of Dingxi Prefecture, etc. According to the program of new strain selection, this new strain was selected for several year's after the dry seeds of Gansu Angelica sinensis(Oliv)Diels 90-01 was irradiated by ions of 55 MeV/u 40 Ar +15 . During the period of year 2005-2007, region experiments of Angelica sinensis (Oliv)Diels new strain DGA2000-02 were developed in Minxian, Weiyuan, Zhangxian and Longxi etc. Average yield of the fresh DGA2000-02 Angelica was 10 621.5 kg/hm 2 , and 15.0% production was increased more than control (for 1 386.0 kg/hm 2 of 90-01). The growth stage of the DGA2000-02 was 790 d, and it has deep purple stem and yellow-white root. The quality analysis results are as follows: total ash content is 4.2% and acidast ash content is 0.4%, 16% and 33.3% better than control, respectively; the lixivium is 61.4%, i.e., 4.4% more than the standard of Pharmacopoeia of People's Republic of China (2005 edition); the ferullc acid content is 0.148%, i.e., 2.96 times ligher than the standard. All these results showed that the quality of the DGA2000-02 was better significantly than both control and the standard. It can be grown appropriately at the high, cold and dankness regions at the altitude of 2000-2600 m and with a annual precipitation of 500-600 mm. (authors)

  5. Inactivated polio vaccine development for technology transfer using attenuated Sabin poliovirus strains to shift from Salk-IPV to Sabin-IPV.

    Science.gov (United States)

    Bakker, Wilfried A M; Thomassen, Yvonne E; van't Oever, Aart G; Westdijk, Janny; van Oijen, Monique G C T; Sundermann, Lars C; van't Veld, Peter; Sleeman, Eelco; van Nimwegen, Fred W; Hamidi, Ahd; Kersten, Gideon F A; van den Heuvel, Nico; Hendriks, Jan T; van der Pol, Leo A

    2011-09-22

    Industrial-scale inactivated polio vaccine (IPV) production dates back to the 1960s when at the Rijks Instituut voor de Volksgezondheid (RIV) in Bilthoven a process was developed based on micro-carrier technology and primary monkey kidney cells. This technology was freely shared with several pharmaceutical companies and institutes worldwide. In this contribution, the history of one of the first cell-culture based large-scale biological production processes is summarized. Also, recent developments and the anticipated upcoming shift from regular IPV to Sabin-IPV are presented. Responding to a call by the World Health Organization (WHO) for new polio vaccines, the development of Sabin-IPV was continued, after demonstrating proof of principle in the 1990s, at the Netherlands Vaccine Institute (NVI). Development of Sabin-IPV plays an important role in the WHO polio eradication strategy as biocontainment will be critical in the post-OPV cessation period. The use of attenuated Sabin strains instead of wild-type Salk polio strains will provide additional safety during vaccine production. Initially, the Sabin-IPV production process will be based on the scale-down model of the current, and well-established, Salk-IPV process. In parallel to clinical trial material production, process development, optimization and formulation research is being carried out to further optimize the process and reduce cost per dose. Also, results will be shown from large-scale (to prepare for future technology transfer) generation of Master- and Working virus seedlots, and clinical trial material (for phase I studies) production. Finally, the planned technology transfer to vaccine manufacturers in low and middle-income countries is discussed. Copyright © 2011 Elsevier Ltd. All rights reserved.

  6. Improvement of selected strains through gamma irradiation for enhanced lipolytic potential

    International Nuclear Information System (INIS)

    Iftikhar, T.; Mubashir, N.; Hussain, Y.; Abbas, S.Q.; Ashraf, I.

    2010-01-01

    The purpose of the present investigation was to enhance the production of industrially important enzyme lipase by subjecting the wild lipase producing fungal strains i.e. Aspergillus niger, Rhizopus microsporus and Penicillium atrovenetum to various doses of gamma irradiation (20, 40, 60, 80, 100, 120, 140 and 160 Gy). The isolation and lipolytic activity of selected mutant derived strains is described in this paper. Among all the mutants tested, MBL-5 obtained at 140Gy of Aspergillus niger strain showed highest extracellular lipase activity (13.75 +- 0.15 U mL/sup -1/) while MBL-1 Rhizopus microsporus at the rate 20Gy showed the lowest activity i.e., 1.06 +- 0.11 U mL/sup -1/. A range of pH 3, 5, 7, 9 and 11 was used to check the lipolytic potential of various mutants along with their wild type. It was observed that MBL-5 (Aspergillus niger) and MBL-2 (Rhizopus microsporus) showed enhanced extracellular lipase activity at pH 11 while MBL-3 (Penicillium atrovenetum) showed the highest extracellular lipase activity 22.53 +- 0.21 U mL/sup -1/ at pH 9. It indicates a possible role for the MBL-2, MBL-3 and MBL-5 mutant strains in the detergent industry for the development of eco-friendly technologies. (author)

  7. Trypanosoma cruzi: strain selection by diferent schedules of mouse passage of an initially mixed infection

    Directory of Open Access Journals (Sweden)

    Maria P. Deane

    1984-12-01

    Full Text Available From an initial double infection in mice, established by simultaneous and equivalent inocula of bloodstream forms of strains Y and F of Trypanosoma cruzi, two lines were derived by subinoculations: one (W passaged every week, the other (M every month. Through biological and biochemical methods only the Y strain was identified at the end of the 10th and 16th passages of line W and only the F strain at the 2nd and 4th passages of line M. The results illustrate strain selection through laboratory manipulation of initially mixed populations of T. cruzi.De uma infecção inicialmente dupla em camundongo, estabelecida por inóculo simultaneo e equivalente de formas sanguíneas das cepas Y e F de Trypanosoma cruzi, duas linhagens foram originadas por subinoculações: uma (W passada casa semana, a outra (M cada mês. Por métodos biológicos e bioquímicos apenas a cepa Y foi identificada ao fim a 10a. e 16a. passagens da linhagem W e apenas a cepa F na 2a. e 4a.passagens de linhagem M. Os resultados demonstram a seleção de cepas através de manipulação em laboratorio de populações inicialmente mistas de T. cruzi.

  8. Selected wild strains of Agaricus bisporus produce high yields of mushrooms at 25°C.

    Science.gov (United States)

    Navarro, Pilar; Savoie, Jean-Michel

    2015-01-01

    To cultivate the button mushroom Agaricus bisporus in warm countries or during summer in temperate countries, while saving energy, is a challenge that could be addressed by using the biological diversity of the species. The objective was to evaluate the yield potential of eight wild strains previously selected in small scale experiments for their ability to produce mature fruiting bodies at 25°C and above. Culture units of 8 kg of compost were used. The yield expressed as weight or number per surface unit and earliness of fruiting were recorded during cultivation in climatic rooms at 17, 25 or 30°C. Only strains of A. bisporus var. burnettii were able to fruit at 30°C. At 25°C they produced the highest yields (27 kg m(-2)) and had best earliness. The yields at 25°C for the strains of A. bisporus var. bisporus ranged from 12 to 16 kg m(-2). The yield ratios 25°C/17°C ranged from 0.8 to 1.2. The variety burnettii originated in the Sonoran Desert in California showed adaptation for quickly producing fruiting bodies at high temperature when humidity conditions were favorable. Strains of the variety bisporus showed interesting potentials for their ability to produce mature fruiting bodies at higher temperature than present cultivars and might be used in breeding programs. Copyright © 2012 Revista Iberoamericana de Micología. Published by Elsevier Espana. All rights reserved.

  9. Sequence analysis of chromosome 1 revealed different selection patterns between Chinese wild mice and laboratory strains.

    Science.gov (United States)

    Xu, Fuyi; Hu, Shixian; Chao, Tianzhu; Wang, Maochun; Li, Kai; Zhou, Yuxun; Xu, Hongyan; Xiao, Junhua

    2017-10-01

    Both natural and artificial selection play a critical role in animals' adaptation to the environment. Detection of the signature of selection in genomic regions can provide insights for understanding the function of specific phenotypes. It is generally assumed that laboratory mice may experience intense artificial selection while wild mice more natural selection. However, the differences of selection signature in the mouse genome and underlying genes between wild and laboratory mice remain unclear. In this study, we used two mouse populations: chromosome 1 (Chr 1) substitution lines (C1SLs) derived from Chinese wild mice and mouse genome project (MGP) sequenced inbred strains and two selection detection statistics: Fst and Tajima's D to identify the signature of selection footprint on Chr 1. For the differentiation between the C1SLs and MGP, 110 candidate selection regions containing 47 protein coding genes were detected. A total of 149 selection regions which encompass 7.215 Mb were identified in the C1SLs by Tajima's D approach. While for the MGP, we identified nearly twice selection regions (243) compared with the C1SLs which accounted for 13.27 Mb Chr 1 sequence. Through functional annotation, we identified several biological processes with significant enrichment including seven genes in the olfactory transduction pathway. In addition, we searched the phenotypes associated with the 47 candidate selection genes identified by Fst. These genes were involved in behavior, growth or body weight, mortality or aging, and immune systems which align well with the phenotypic differences between wild and laboratory mice. Therefore, the findings would be helpful for our understanding of the phenotypic differences between wild and laboratory mice and applications for using this new mouse resource (C1SLs) for further genetics studies.

  10. Brucella suis vaccine strain 2 induces endoplasmic reticulum stress that affects intracellular replication in goat trophoblast cells in vitro

    Directory of Open Access Journals (Sweden)

    Xiangguo eWang

    2016-02-01

    Full Text Available Brucella has been reported to impair placental trophoblasts, a cellular target where Brucella efficiently replicates in association with the endoplasmic reticulum (ER, and ultimately trigger abortion in pregnant animals. However, the precise effects of Brucella on trophoblast cells remain unclear. Here, we describe the infection and replication of Brucella suis vaccine strain 2 (B.suis.S2 in goat trophoblast cells (GTCs and the cellular and molecular responses induced in vitro. Our studies demonstrated that B.suis.S2 was able to infect and proliferate to high titers, hamper the proliferation of GTCs and induce apoptosis due to ER stress. Tunicamycin (Tm, a pharmacological chaperone that strongly mounts ER stress-induced apoptosis, inhibited B.suis.S2 replication in GTCs. In addition, 4 phenyl butyric acid (4-PBA, a pharmacological chaperone that alleviates ER stress-induced apoptosis, significantly enhanced B.suis.S2 replication in GTCs. The Unfolded Protein Response (UPR chaperone molecule GRP78 also promoted B.suis.S2 proliferation in GTCs by inhibiting ER stress-induced apoptosis. We also discovered that the IRE1 pathway, but not the PERK or ATF6 pathway, was activated in the process. However, decreasing the expression of phosphoIRE1α and IRE1α proteins with Irestatin 9389 (IRE1 antagonist in GTCs did not affect the proliferation of B.suis.S2. Although GTC implantation was not affected upon B.suis.S2 infection, progesterone secretion was suppressed, and prolactin and estrogen secretion increased; these effects were accompanied by changes in the expression of genes encoding key steroidogenic enzymes. This study systematically explored the mechanisms of abortion in Brucella infection from the viewpoint of pathogen invasion, ER stress and reproductive endocrinology. Our findings may provide new insight for understanding the mechanisms involved in goat abortions caused by Brucella infection.

  11. SELECTED PARAMETERS OF THE WORK OF SPEED LIMITER IN LINE STRAINING SYSTEM IN A FRICTIONAL LIFT

    Directory of Open Access Journals (Sweden)

    Paweł Lonkwic

    2014-03-01

    Full Text Available The article presents the analysis of selected work parameters of speed limiter in line straining system. We analyzed the effect of changing the geometrical conditions of the new solution for the speed limiter in line straining system upon the working conditions in frictional lift braking system. Within the conducted simulations of the work of the system, which is responsible for lift braking with a tension with spring, a test bed was prepared, which simulated the work of tension-rope-limiter system. The tests were performed in the conditions reflecting the work of a lifting appliance. Analyzing the results obtained through empirical calculations, we can conclude that there is a possibility of applying the spring to eliminate the weight.

  12. [Comparison on agronomy and quality characters of selective strain of Schizonepeta tenuifolia].

    Science.gov (United States)

    Cao, Liang; Jin, Yue; Wei, Jianhe; Chu, Qinglong; Zhao, Runhuai; Wang, Weiquan

    2009-05-01

    With the purpose of selecting adequate quality and high production of Schizonepeta tenuifolia, the comparative experiments were carried out on different strain of S. tenuifolia in 2007. The test fields were divided into blocks randomly, and the agronomy characters were investigated in harvest time; the content of volatile oil was measured by steam distillation and the pulegone were determined by HPLC. The yield of S4 was 18.63% and 29.99% higher than that of CK1 and CK2, respectively. The contents of volatile oil and pulegone were also higher than those of CK and other strains in this test. S4 shows the advantages of high production, strong disease resistance and high active components. S4 would be extended as the good breed in production.

  13. Role of some selected Bifidobacterium strains in modulating immunosenescence of aged albino rats

    Directory of Open Access Journals (Sweden)

    Hanan A. El-Bakry

    2013-10-01

    Full Text Available Probiotic administration has been associated with enhanced immune function in elderly subjects. However, approaches for selection of an “ideal” strain of bifidobacteria are still difficult. The aim of the present study is to investigate the possible modulatory effects of three strains of Bifidobacterium species (Bifidobacterium adolescentis ATCC 15704, Bifidobacterium breve ATCC 15700 and Bifidobacterium longum ATCC 15707 on haematological and immunological parameters of aged albino rats corresponding to normal adult ones. The animals were divided into six groups; three groups of aged rats were fed yoghurt inoculated with one of the Bifidobacterium strains; one group of aged rats was fed yoghurt alone (control aged; two groups of adult and aged rats were provided with normal diet and assigned as normal groups. The total leucocyte count was significantly increased in the three bifidobacteria-treated aged groups as compared with both normal and control aged rats. Serum IgA level was considerably increased in all treated rats. On the contrary, serum IgE level was significantly decreased in rats supplemented with yoghurt inoculated with B. adolescentis or B. breve. Both B. adolescentis and B. breve groups showed significant enhanced production of TNF-α. Furthermore, the production of cytokine IL-8 was significantly increased in the B. adolescentis group. Interestingly, it was apparent that only B. adolescentis had the most pronounced effect on aged rats to regain nearly normal values as measured in normal adult rats. Conclusively, the present work indicates that dietary consumption of selected bifidobacteria strains may have a particular application in the elderly especially in terms of immunomodulation.

  14. Analysis of bluetongue serotype 3 spread in Tunisia and discovery of a novel strain related to the bluetongue virus isolated from a commercial sheep pox vaccine.

    Science.gov (United States)

    Lorusso, Alessio; Sghaier, Soufien; Di Domenico, Marco; Barbria, Mohamed Elias; Zaccaria, Guendalina; Megdich, Aida; Portanti, Ottavio; Seliman, Imed Ben; Spedicato, Massimo; Pizzurro, Federica; Carmine, Irene; Teodori, Liana; Mahjoub, Mejdi; Mangone, Iolanda; Leone, Alessandra; Hammami, Salah; Marcacci, Maurilia; Savini, Giovanni

    2018-04-01

    Bluetongue (BT), is one of the OIE-listed major diseases of ruminants. Following the official report of BT virus serotype 3 (BTV-3) in a sheep in Cap Bon (Tunisia), blood and serum samples of ruminants were collected from some areas of Tunisia to further investigate the presence of this virus in the country. A quantitative real time RT-PCR has been first developed for the detection and quantitation of BTV-3 RNA from field specimens. Out of 62 collected blood samples, 23 were shown to be positive for BTV-3 RNA. Isolation on cell cultures was also possible from six samples. Genome sequencing revealed the circulation of two unrelated western strains of BTV-3, one circulating in Cap Bon and neighboring areas, and the other circulating nearby the border with Libya. The presence of a putative novel BTV serotype (BTV-Y TUN2017) in sheep introduced from Libya to Tunisia, genomically related to the BTV strain contaminating a commercially-available sheep pox vaccine and to BTV-26, has been also demonstrated. This finding highlights the pressing need for a prompt production and release of a novel inactivated BTV-3 vaccine to be used in case of emergence or proactively in the areas of Southern Europe at major risk of BTV introduction. The assessment of a novel vaccine will certainly exalt the role and importance of surveillance activities and collaboration with Northern African countries. Copyright © 2018 Elsevier B.V. All rights reserved.

  15. Yellow fever vaccine: comparison of the neurovirulence of new 17D-204 Stamaril™ seed lots and RK 168-73 strain.

    Science.gov (United States)

    Moulin, Jean-Claude; Silvano, Jérémy; Barban, Véronique; Riou, Patrice; Allain, Caroline

    2013-07-01

    The neurovirulence of two new candidate 17D-204 Stamaril™ working seed lots and that of two reference preparations were compared. The Stamaril™ working seed lots have been used for more than twenty years for the manufacturing of vaccines of acceptable safety and efficacy. The preparation designated RK 168-73 and provided by the Robert Koch Institute was used as a reference. It was confirmed that RK 168-73 strain was not a good virus control in our study because it has a very low neurovirulence regarding both the clinical and histopathological scores in comparison with Stamaril™ strain and is not representative of a vaccine known to be satisfactory in use. The results were reinforced by the phenotypic characterization by plaque assay demonstrating that RK 168-73 was very different from the Stamaril™ vaccine, and by sequencing results showing 4 mutations between Stamaril™ and RK 168-73 viruses leading to amino acid differences in the NS4B and envelop proteins. Copyright © 2013 The International Alliance for Biological Standardization. Published by Elsevier Ltd. All rights reserved.

  16. Construction of a recombinant Lactococcus lactis strain expressing a fusion protein of Omp22 and HpaA from Helicobacter pylori for oral vaccine development.

    Science.gov (United States)

    Zhang, Rongguang; Duan, Guangcai; Shi, Qingfeng; Chen, Shuaiyin; Fan, Qingtang; Sun, Nan; Xi, Yuanlin

    2016-11-01

    To develop orally administrated anti-Helicobacter pylori vaccination, a Lactococcus lactis strain was genetically constructed for fusion expression of H. pylori protective antigens HpaA and Omp22. The fusion gene of omp22 and hpaA with an adapter encoding three glycines was cloned from a plasmid pMAL-c2x-omp22-hpaA into Escherichia coli MC1061 and L. lactis NZ3900 successively using a shutter vector pNZ8110. Expression of the fusion gene in L. lactis was induced with nisin resulting in production of proteins with molecular weights of 50 and 28 kDa. Both of them were immunoreactive with mouse anti-H. pylori sera as determined via western blotting. Oral vaccination of BALB/c mice using the L. lactis strain carrying pNZ8110-omp22-hpaA elicited significant systematic humoral immune response (P lactis with immunogenicity. This is a considerable step towards H. pylori vaccines.

  17. Full Genome Characterisation of Bluetonge Virus Seroptype 6 from the Netherlands 2008 and Comparison to Other Field and Vaccine Strains

    NARCIS (Netherlands)

    Maan, S.; Maan, N.S.; Rijn, van P.A.; Gennip, van H.G.P.; Sanders, A.A.; Wright, I.M.; Batten, C.; Hoffmann, B.; Eschbaumer, M.; Oura, C.A.L.; Potgieter, C.; Nomikou, K.; Mertens, P.P.C.

    2010-01-01

    In mid September 2008, clinical signs of bluetongue (particularly coronitis) were observed in cows on three different farms in eastern Netherlands (Luttenberg, Heeten, and Barchem), two of which had been vaccinated with an inactivated BTV-8 vaccine (during May-June 2008). Bluetongue virus (BTV)

  18. Molecular typing of canine parvovirus strains circulating from 2008 to 2012 in an organized kennel in India reveals the possibility of vaccination failure.

    Science.gov (United States)

    Mittal, Mitesh; Chakravarti, Soumendu; Mohapatra, J K; Chug, P K; Dubey, Rahul; Upmanuyu, Vikramaditya; Narwal, P S; Kumar, Anil; Churamani, C P; Kanwar, N S

    2014-04-01

    Canine parvovirus-2 (CPV-2), which emerged in 1978, is considered as the major viral enteric pathogen of the canine population. With the emergence of new antigenic variants and incidences of vaccine failure, CPV has become one of the dreaded diseases of the canines worldwide. The present study was undertaken in an organized kennel from North India to ascertain the molecular basis of the CPV outbreaks in the vaccinated dogs. 415 samples were collected over a 5year period (2008-2012). The outbreak of the disease was more severe in 2012 with high incidence of mortality in pups with pronounced clinical symptoms. Molecular typing based on the VP2 gene was carried out with the 11 isolates from different years and compared with the CPV prototype and the vaccine strains. All the isolates in the study were either new CPV-2a (2012 isolates) or new CPV-2b (2008 and 2011 isolates). There were amino acid mutations at the Tyr324Ile and at the Thr440Ala position in five isolates from 2012 indicating new CPV mutants spreading in India. The CPV vaccines used in the present study failed to generate protective antibody titer against heterogeneous CPV antigenic types. The findings were confirmed when the affected pups were treated with hyper-immune heterogeneous purified immunoglobulin's against CPV in dogs of different antigenic types. Copyright © 2014 Elsevier B.V. All rights reserved.

  19. Controversy and debate on dengue vaccine series-paper 1: review of a licensed dengue vaccine: inappropriate subgroup analyses and selective reporting may cause harm in mass vaccination programs.

    Science.gov (United States)

    Dans, Antonio L; Dans, Leonila F; Lansang, Mary Ann D; Silvestre, Maria Asuncion A; Guyatt, Gordon H

    2018-03-01

    Severe life-threatening dengue fever usually occurs when a child is infected by dengue virus a second time. This is caused by a phenomenon called antibody-dependent enhancement (ADE). Since dengue vaccines can mimic a first infection in seronegative children (those with no previous infection), a natural infection later in life could lead to severe disease. The possibility that dengue vaccines can cause severe dengue through ADE has led to serious concern regarding the safety of mass vaccination programs. A published meta-analysis addressed this safety issue for a new vaccine against dengue fever-Dengvaxia. The trials in this meta-analysis have been used to campaign for mass vaccination programs in developing countries. We discuss the results of this paper and point out problems in the analyses. Reporting the findings in an Asian trial (CYD14), the authors show a sevenfold rise in one outcome-hospitalization for dengue fever in children <5 years old. However, they fail to point out two signals of harm for another outcome-hospitalization for severe dengue fever (as confirmed by an independent data monitoring committee): 1. In children younger than 9 years, the relative risk was 8.5 (95% confidence interval [CI]: 0.5, 146.8), and 2. In the overall study group, the relative risk was 5.5 (95% CI: 0.9, 33). The authors conduct a subgroup analysis to support claims that the vaccine is probably safe among children aged 9 years or more. This subgroup analysis has limited credibility because: (1) it was a post hoc analysis; (2) it was one of a large number of subgroup analyses; (3) the test of interaction was not reported, but was insignificant (P = 0.14); and (4) there is no biological basis for a threshold age of 9 years. The more likely explanation for the higher risk in younger children is ADE, that is, more frequent seronegativity, rather than age itself. The selective reporting and inappropriate subgroup claims mask the potential harm of dengue mass vaccination

  20. Susceptibility of Meningococcal Strains Responsible for Two Serogroup B Outbreaks on U.S. University Campuses to Serum Bactericidal Activity Elicited by the MenB-4C Vaccine.

    Science.gov (United States)

    Rossi, Raffaella; Beernink, Peter T; Giuntini, Serena; Granoff, Dan M

    2015-12-01

    In 2013 and 2014, two U.S. universities had meningococcal serogroup B outbreaks (a total of 14 cases) caused by strains from two different clonal complexes. To control the outbreaks, students were immunized with a serogroup B meningococcal vaccine (Novartis) that was not yet licensed in the United States. The vaccine (referred to as MenB-4C) contains four components capable of eliciting bactericidal activity. Both outbreak strains had high expression levels of two of the vaccine antigens (subfamily B factor H binding protein [FHbp] and neisserial heparin binding antigen [NHba]); the university B outbreak strain also had moderate expression of a third antigen, NadA. We investigated the bactericidal activity of sera from mice immunized with FHbp, NHba, or NadA and sera from MenB-4C-immunized infant macaques and an adult human. The postimmunization bactericidal activity of the macaque or human serum against isolates from university B with FHbp identification (ID) 1 that exactly matched the vaccine FHbp sequence variant was 8- to 21-fold higher than that against isolates from university A with FHbp ID 276 (96% identity to the vaccine antigen). Based on the bactericidal activity of mouse antisera to FHbp, NadA, or NHba and macaque or human postimmunization serum that had been depleted of anti-FHbp antibody, the bactericidal activity against both outbreak strains largely or entirely resulted from antibodies to FHbp. Thus, despite the high level of strain expression of FHbp from a subfamily that matched the vaccine antigen, there can be large differences in anti-FHbp bactericidal activity induced by MenB-4C vaccination. Further, strains with moderate to high NadA and/or NHba expression can be resistant to anti-NadA or anti-NHba bactericidal activity elicited by MenB-4C vaccination. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

  1. The genomic landscape shaped by selection on transposable elements across 18 mouse strains.

    Science.gov (United States)

    Nellåker, Christoffer; Keane, Thomas M; Yalcin, Binnaz; Wong, Kim; Agam, Avigail; Belgard, T Grant; Flint, Jonathan; Adams, David J; Frankel, Wayne N; Ponting, Chris P

    2012-06-15

    Transposable element (TE)-derived sequence dominates the landscape of mammalian genomes and can modulate gene function by dysregulating transcription and translation. Our current knowledge of TEs in laboratory mouse strains is limited primarily to those present in the C57BL/6J reference genome, with most mouse TEs being drawn from three distinct classes, namely short interspersed nuclear elements (SINEs), long interspersed nuclear elements (LINEs) and the endogenous retrovirus (ERV) superfamily. Despite their high prevalence, the different genomic and gene properties controlling whether TEs are preferentially purged from, or are retained by, genetic drift or positive selection in mammalian genomes remain poorly defined. Using whole genome sequencing data from 13 classical laboratory and 4 wild-derived mouse inbred strains, we developed a comprehensive catalogue of 103,798 polymorphic TE variants. We employ this extensive data set to characterize TE variants across the Mus lineage, and to infer neutral and selective processes that have acted over 2 million years. Our results indicate that the majority of TE variants are introduced though the male germline and that only a minority of TE variants exert detectable changes in gene expression. However, among genes with differential expression across the strains there are twice as many TE variants identified as being putative causal variants as expected. Most TE variants that cause gene expression changes appear to be purged rapidly by purifying selection. Our findings demonstrate that past TE insertions have often been highly deleterious, and help to prioritize TE variants according to their likely contribution to gene expression or phenotype variation.

  2. Green revolution vaccines, edible vaccines | Tripurani | African ...

    African Journals Online (AJOL)

    Edible vaccines are sub-unit vaccines where the selected genes are introduced into the plants and the transgenic plant is then induced to manufacture the encoded protein. Edible vaccines are mucosal-targeted vaccines where stimulation of both systematic and mucosal immune network takes place. Foods under study ...

  3. Detection and differentiation of wild-type and vaccine strains of canine distemper virus by a duplex reverse transcription polymerase chain reaction.

    Science.gov (United States)

    Dong, X Y; Li, W H; Zhu, J L; Liu, W J; Zhao, M Q; Luo, Y W; Chen, J D

    2015-01-01

    Canine distemper virus (CDV) is the cause of canine distemper (CD) which is a severe and highly contagious disease in dogs. In the present study, a duplex reverse transcription polymerase chain reaction (RT-PCR) method was developed for the detection and differentiation of wild-type and vaccine strains of CDV. Four primers were designed to detect and discriminate the two viruses by generating 638- and 781-bp cDNA products, respectively. Furthermore, the duplex RT-PCR method was used to detect 67 field samples suspected of CD from Guangdong province in China. Results showed that, 33 samples were to be wild-type-like. The duplex RT-PCR method exhibited high specificity and sensitivity which could be used to effectively detect and differentiate wild-type and vaccine CDV, indicating its use for clinical detection and epidemiological surveillance.

  4. Antifungal activity of plant essential oils and selected Pseudomonas strains against Phomopsis theicola

    Directory of Open Access Journals (Sweden)

    Starović Mira

    2017-01-01

    Full Text Available Development of natural plant protection products as an alternative to synthetic fungicides is of significant importance regarding the environment. This study was carried out with an objective to investigate in vitro antifungal activities of several essential oils extracted from oregano, basil, myrtle and Turkish pickling herb, and the plant growth-promoting rhizobacteria in the genus Pseudomonas, against the phytopathogenic fungus Phomopsis theicola. Microdilution methods were used to determine the minimum inhibitory concentrations (MIC of selected antimicrobial essential oils (EOs. All EOs exhibited significant levels of antifungal activity against the tested fungal isolates. The oregano EO was found the most potent one (MIC - 5.5 µg/mL, followed by basil (MIC - 75.0µg/mL, myrtle (MIC - 775 µg/mL and Turkish pickling herb (MIC - 7750 µg/mL. Inhibition of Ph. theicola mycelial growth was observed for all tested Pseudomonas spp. strains. K113 and L1 strains were highly effective and achieved more than 60% of fungal growth inhibition using the overnight culture and more than 57% inhibition by applying cell-free supernatants of both strains. A future field trial with K113 and L1 cultures and cell-free supernatants, containing extracellular metabolites toward Ph. theicola, will estimate their effectiveness and applicability as an alternative to chemical protection of apple trees.

  5. High level of Bcl-2 counteracts apoptosis mediated by a live rabies virus vaccine strain and induces long-term infection

    International Nuclear Information System (INIS)

    Thoulouze, Maria-Isabel; Lafage, Mireille; Yuste, Victor J.; Baloul, Leiela; Edelman, Lena; Kroemer, Guido; Israel, Nicole; Susin, Santos A.; Lafon, Monique

    2003-01-01

    We report here that rabies virus strains, currently used to immunize wildlife against rabies, induce not only caspase-dependent apoptosis in the human lymphoblastoid Jurkat T cell line (Jurkat-vect), but also a caspase-independent pathway involving the apoptosis-inducing factor (AIF). In contrast, a strain of neurotropic RV that does not induce apoptosis did not activate caspases or induce AIF translocation. Bcl-2 overproduction in Jurkat T cells (Jurkat-Bcl-2) abolished both pathways. ERA infection and production were similar in Jurkat-vect and Jurkat-Bcl-2 cells, indicating Bcl-2 has no direct antiviral effects. Bcl-2 production is naturally upregulated by day 3 in ERA-infected Jurkat-vect cultures. The increase in Bcl-2 levels seems to be controlled by the virus infection itself and results in the establishment of long-term, persistently infected cultures that continue to produce virus. Thus, in infections with live RV vaccine strains, infected cells may be productive reservoirs of virus in the long term. This may account for the high efficacy of live rabies vaccines

  6. Characterization of recombinant B. abortus strain RB51SOD towards understanding the uncorrelated innate and adaptive immune responses induced by RB51SOD compared to its parent vaccine strain RB51

    Directory of Open Access Journals (Sweden)

    Jianguo eZhu

    2011-11-01

    Full Text Available Brucella abortus is a Gram-negative, facultative intracellular pathogen for several mammals, including humans. Live attenuated B. abortus strain RB51 is currently the official vaccine used against bovine brucellosis in the United States and several other countries. Overexpression of protective B. abortus antigen Cu/Zn superoxide dismutase (SOD in a recombinant strain of RB51 (strain RB51SOD significantly increases its vaccine efficacy against virulent B. abortus challenge in a mouse model. An attempt has been made to better understand the mechanism of the enhanced protective immunity of RB51SOD compared to its parent strain RB51. We previously reported that RB51SOD stimulated enhanced Th1 immune response. In this study, we further found that T effector cells derived from RB51SOD-immunized mice exhibited significantly higher cytotoxic T lymphocyte (CTL activity than T effector cells derived from RB51-immunized mice against virulent B. abortus-infected target cells. Meanwhile, the macrophage responses to these two strains were also studied. Compared to RB51, RB51SOD cells had a lower survival rate in macrophages and induced lower levels of macrophage apoptosis and necrosis. The decreased survival of RB51SOD cells correlates with the higher sensitivity of RB51SOD, compared to RB51, to the bactericidal action of either Polymyxin B or sodium dodecyl sulfate (SDS. Furthermore, a physical damage to the outer membrane of RB51SOD was observed by electron microscopy. Possibly due to the physical damage, overexpressed Cu/Zn SOD in RB51SOD was found to be released into the bacterial cell culture medium. Therefore, the stronger adaptive immunity induced by RB51SOD did not correlate with the low level of innate immunity induced by RB51SOD compared to RB51. This unique and apparently contradictory profile is likely associated with the differences in outer membrane integrity and Cu/Zn SOD release.

  7. A small animal peripheral challenge model of yellow fever using interferon-receptor deficient mice and the 17D-204 vaccine strain.

    Science.gov (United States)

    Thibodeaux, Brett A; Garbino, Nina C; Liss, Nathan M; Piper, Joseph; Blair, Carol D; Roehrig, John T

    2012-05-02

    Yellow fever virus (YFV), a member of the genus Flavivirus, is a mosquito-borne pathogen that requires wild-type (wt), virulent strains to be handled at biosafety level (BSL) 3, with HEPA-filtration of room air exhaust (BSL3+). YFV is found in tropical regions of Africa and South America and causes severe hepatic disease and death in humans. Despite the availability of effective vaccines (17D-204 or 17DD), YFV is still responsible for an estimated 200,000 cases of illness and 30,000 deaths annually. Besides vaccination, there are no other prophylactic or therapeutic strategies approved for use in human YF. Current small animal models of YF require either intra-cranial inoculation of YF vaccine to establish infection, or use of wt strains (e.g., Asibi) in order to achieve pathology. We have developed and characterized a BSL2, adult mouse peripheral challenge model for YFV infection in mice lacking receptors for interferons α, β, and γ (strain AG129). Intraperitoneal challenge of AG129 mice with 17D-204 is a uniformly lethal in a dose-dependent manner, and 17D-204-infected AG129 mice exhibit high viral titers in both brain and liver suggesting this infection is both neurotropic and viscerotropic. Furthermore the use of a mouse model permitted the construction of a 59-biomarker multi-analyte profile (MAP) using samples of brain, liver, and serum taken at multiple time points over the course of infection. This MAP serves as a baseline for evaluating novel therapeutics and their effect on disease progression. Changes (4-fold or greater) in serum and tissue levels of pro- and anti-inflammatory mediators as well as other factors associated with tissue damage were noted in AG129 mice infected with 17D-204 as compared to mock-infected control animals. Published by Elsevier Ltd.

  8. Differences in Attack Avoidance and Mating Success between Strains Artificially Selected for Dispersal Distance in Tribolium castaneum.

    Directory of Open Access Journals (Sweden)

    Kentarou Matsumura

    Full Text Available Individuals of both dispersal and non-dispersal types (disperser and non-disperser are found in a population, suggesting that each type has both costs and benefits for fitness. However, few studies have examined the trade-off between the costs and benefits for the types. Here, we artificially selected for walking distance, i.e., an indicator of dispersal ability, in the red flour beetle Tribolium castaneum and established strains with longer (L-strains or shorter (S-strains walking distances. We then compared the frequency of predation by the assassin bug Amphibolus venator and the mating frequency of the selected strains. L-strain beetles suffered higher predation risk, than did S-strain beetles. L-strain males had significantly increased mating success compared to S-strain males, but females did not show a significant difference between the strains. The current results showed the existence of a trade-off between predation avoidance and mating success associated with dispersal types at a genetic level only in males. This finding can help to explain the maintenance of variation in dispersal ability within a population.

  9. Development of a combined canine distemper virus specific RT-PCR protocol for the differentiation of infected and vaccinated animals (DIVA) and genetic characterization of the hemagglutinin gene of seven Chinese strains demonstrated in dogs.

    Science.gov (United States)

    Yi, Li; Cheng, Shipeng; Xu, Hongli; Wang, Jianke; Cheng, Yuening; Yang, Shen; Luo, Bin

    2012-01-01

    A combined reverse-transcription polymerase chain reaction (RT-PCR) method was developed for the detection and differentiation of wild-type and vaccine strains of the canine distemper virus (CDV). A pair of primers (P1/P2) was used to detect both CDV wild-type strains and vaccines. Another pair (P3/P4) was used to detect only CDV wild-type strains. A 335bp fragment was amplified from the genomic RNA of the vaccine and wild-type strains. A 555bp fragment was amplified specifically from the genomic RNA of the wild-type strains. No amplification was achieved for the uninfected cells, cells infected with canine parvovirus, canine coronavirus, or canine adenovirus. The combined RT-PCR method detected effectively and differentiated the CDV wild-type and vaccine strains by two separate RT-PCRs. The method can be used for clinical detection and epidemiological surveillance. The phylogenetic analysis of the hemagglutinin gene of the local wild-type CDV strains revealed that the seven local isolates all belonged to the Asia-1 lineage, and were clustered closely with one another at the same location. These results suggested that the CDV genotype Asia-1 is circulating currently in domestic dogs in China. Copyright © 2011 Elsevier B.V. All rights reserved.

  10. Multiple antigens of Yersinia pestis delivered by live recombinant attenuated Salmonella vaccine strains elicit protective immunity against plague.

    Science.gov (United States)

    Sanapala, Shilpa; Rahav, Hannah; Patel, Hetal; Sun, Wei; Curtiss, Roy

    2016-05-05

    Based on our improved novel Salmonella vaccine delivery platform, we optimized the recombinant attenuated Salmonella typhimurium vaccine (RASV) χ12094 to deliver multiple Yersinia pestis antigens. These included LcrV196 (amino acids, 131-326), Psn encoded on pYA5383 and F1 encoded in the chromosome, their synthesis did not cause adverse effects on bacterial growth. Oral immunization with χ12094(pYA5383) simultaneously stimulated high antibody titers to LcrV, Psn and F1 in mice and presented complete protection against both subcutaneous (s.c.) and intranasal (i.n.) challenges with high lethal doses of Y. pestis CO92. Moreover, no deaths or other disease symptoms were observed in SCID mice orally immunized with χ12094(pYA5383) over a 60-day period. Therefore, the trivalent S. typhimurium-based live vaccine shows promise for a next-generation plague vaccine. Copyright © 2016 Elsevier Ltd. All rights reserved.

  11. Selection of Trichogramma strains and determination of number of parasitoids to be released to control Gymnandrosoma aurantianum Lima (Lepidoptera, Tortricidae)

    International Nuclear Information System (INIS)

    Molina, Rosa Maria da Silva; Parra, Jose Roberto Postali

    2006-01-01

    In order to select Trichogramma strains to control G. aurantianum, the biological characteristics of 13 Trichogramma species/strains were evaluated. After selection, the ideal number of T. pretiosum (G18 strain) to be released per G. aurantianum egg was determined in greenhouse tests. The selection test for species/strains was carried out in an incubator adjusted to 25 +- 1 deg C, RH 70 +- 10%, and a 14 h photo phase. The ideal number of parasitoids was estimated in cages covered with a piece of voile-type fabric. The cycle duration for the 13 Trichogramma species/strains varied from 10.2 to 11.9 days. The Atp strain (T. atopovirilia) showed greater parasitism capacity, with an average of 23.3 parasitized eggs and 77.5% parasitism in 24 hours. The G18 strain (T. pretiosum) came next, with an average of 16.8 parasitized eggs and 56.1% parasitism during the same time interval. The emergency, longevity of males, and sex ratio for the 13 species/strains were similar. The number of adults emerged per egg was 1.8 for strains G11 (T. pretiosum) and Br10 (T. bruni), which were different from the G3 strain (T. pretiosum) only, with 1.3 adults per egg. With regard to female longevity, distinct values were observed only between T. pretiosum strains Tp and L2, with 6.3 and 9.3 days, respectively. Under greenhouse conditions, the estimated ratio of 36 T. pretiosum parasitoids per G. aurantianum egg allowed the highest percentage of parasitism (89%). Therefore, Trichogramma spp. has a potential to control G. aurantianum, as long as a large number of parasitoids is released per unit area. (author)

  12. The EG95 Antigen of Echinococcus spp. Contains Positively Selected Amino Acids, which May Influence Host Specificity and Vaccine Efficacy

    Science.gov (United States)

    Haag, Karen Luisa; Gottstein, Bruno; Ayala, Francisco Jose

    2009-01-01

    Echinococcosis is a worldwide zoonotic parasitic disease of humans and various herbivorous domestic animals (intermediate hosts) transmitted by the contact with wild and domestic carnivores (definitive hosts), mainly foxes and dogs. Recently, a vaccine was developed showing high levels of protection against one parasite haplotype (G1) of Echinococcus granulosus, and its potential efficacy against distinct parasite variants or species is still unclear. Interestingly, the EG95 vaccine antigen is a secreted glycosylphosphatydilinositol (GPI)-anchored protein containing a fibronectin type III domain, which is ubiquitous in modular proteins involved in cell adhesion. EG95 is highly expressed in oncospheres, the parasite life cycle stage which actively invades the intermediate hosts. After amplifying and sequencing the complete CDS of 57 Echinococcus isolates belonging to 7 distinct species, we uncovered a large amount of genetic variability, which may influence protein folding. Two positively selected sites are outside the vaccine epitopes, but are predicted to alter protein conformation. Moreover, phylogenetic analyses indicate that EG95 isoform evolution is convergent with regard to the number of beta-sheets and alpha-helices. We conclude that having a variety of EG95 isoforms is adaptive for Echinococcus parasites, in terms of their ability to invade different hosts, and we propose that a mixture of isoforms could possibly maximize vaccine efficacy. PMID:19401778

  13. The effect of sire selection on the response of lambs to vaccination with irradiated Trichostrongylus colubriformis larvae

    International Nuclear Information System (INIS)

    Dineen, J.K.; Windon, R.G.

    1980-01-01

    Rams selected for responsiveness and unresponsiveness to vaccination with irradiated T. colubriformis larvae at an early age were mated to unselected random bred ewes. Progeny were vaccinated with 20,000 irradiated larvae at 8 and 12 weeks of age, given anthelmintic treatment at 16 weeks and challenged with 20,000 normal larvae at 17 weeks. The results, based on wether worm counts and ewe faecal egg counts, showed significant differences between responder and non-responder progeny. There was a significant correlation between worm counts and faecal egg counts of half-sibs from the same sire group. The occurrence of globule leucocytes was inversely related to worm burdens of wether progeny, however, no clear relationship was found with eosinophils. In vitro lymphocyte stimulation using T. colubriformis L 3 antigen, concanavalin A and lipopolysaccharide showed that statistically defined responder progeny, pooled from both responder and non-responder sire groups, gave higher responses than non-responder lambs after vaccination. The results confirm that genetically-determined factors are involved in the response of lambs to vaccination at an early age, and indicate that rapid genetic progress may be achieved in the type of mating usually carried out under field conditions. (author)

  14. The study of variability and strain selection in Streptomyces atroolivaceus. III

    International Nuclear Information System (INIS)

    Blumauerova, M.; Lipavska, H.; Stajner, K.; Vanek, Z.

    1976-01-01

    Mutants of Streptomyces atroolivaceus blocked in the biosynthesis of mithramycin were isolated both by natural selection and after treatment with mutagenic factors (UV and gamma rays, nitrous acid). Both physical factors were more effective than nitrous acid. The selection was complicated by the high instability of isolates, out of which 20 to 80%=. (depending on their origin) reversed spontaneously to the parent type. Primary screening (selection of morphological variants and determination of their activity using the method of agar blocks) made it possible to detect only potentially non-productive strains; however, the final selection always had to be made under submerged conditions. Fifty-four stable non-productive mutants were divided, according to results of the chromatographic analysis, into five groups differing in the production of the six biologically inactive metabolites. The mutants did not accumulate chromomycinone, chromocyclomycin and chromocyclin. On mixed cultivation none of the pairs of mutants was capable of the cosynthesis of mithramycin or of new compounds differing from standard metabolites. Possible causes of the above results are discussed. (author)

  15. Selected HIV-1 Env trimeric formulations act as potent immunogens in a rabbit vaccination model.

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    Leo Heyndrickx

    Full Text Available BACKGROUND: Ten to 30% of HIV-1 infected subjects develop broadly neutralizing antibodies (bNAbs during chronic infection. We hypothesized that immunizing rabbits with viral envelope glycoproteins (Envs from these patients may induce bNAbs, when formulated as a trimeric protein and in the presence of an adjuvant. METHODS: Based on in vitro neutralizing activity in serum, patients with bNAbs were selected for cloning of their HIV-1 Env. Seven stable soluble trimeric gp140 proteins were generated from sequences derived from four adults and two children infected with either clade A or B HIV-1. From one of the clade A Envs both the monomeric and trimeric Env were produced for comparison. Rabbits were immunized with soluble gp120 or trimeric gp140 proteins in combination with the adjuvant dimethyl dioctadecyl ammonium/trehalose dibehenate (CAF01. Env binding in rabbit immune serum was determined using ELISAs based on gp120-IIIB protein. Neutralizing activity of IgG purified from rabbit immune sera was measured with the pseudovirus-TZMbl assay and a PBMC-based neutralization assay for selected experiments. RESULTS: It was initially established that gp140 trimers induce better antibody responses over gp120 monomers and that the adjuvant CAF01 was necessary for such strong responses. Gp140 trimers, based on HIV-1 variants from patients with bNAbs, were able to elicit both gp120IIIB specific IgG and NAbs to Tier 1 viruses of different subtypes. Potency of NAbs closely correlated with titers, and an gp120-binding IgG titer above a threshold of 100,000 was predictive of neutralization capability. Finally, peptide inhibition experiments showed that a large fraction of the neutralizing IgG was directed against the gp120 V3 region. CONCLUSIONS: Our results indicate that the strategy of reverse immunology based on selected Env sequences is promising when immunogens are delivered as stabilized trimers in CAF01 adjuvant and that the rabbit is a valuable model

  16. Selected HIV-1 Env trimeric formulations act as potent immunogens in a rabbit vaccination model.

    Science.gov (United States)

    Heyndrickx, Leo; Stewart-Jones, Guillaume; Jansson, Marianne; Schuitemaker, Hanneke; Bowles, Emma; Buonaguro, Luigi; Grevstad, Berit; Vinner, Lasse; Vereecken, Katleen; Parker, Joe; Ramaswamy, Meghna; Biswas, Priscilla; Vanham, Guido; Scarlatti, Gabriella; Fomsgaard, Anders

    2013-01-01

    Ten to 30% of HIV-1 infected subjects develop broadly neutralizing antibodies (bNAbs) during chronic infection. We hypothesized that immunizing rabbits with viral envelope glycoproteins (Envs) from these patients may induce bNAbs, when formulated as a trimeric protein and in the presence of an adjuvant. Based on in vitro neutralizing activity in serum, patients with bNAbs were selected for cloning of their HIV-1 Env. Seven stable soluble trimeric gp140 proteins were generated from sequences derived from four adults and two children infected with either clade A or B HIV-1. From one of the clade A Envs both the monomeric and trimeric Env were produced for comparison. Rabbits were immunized with soluble gp120 or trimeric gp140 proteins in combination with the adjuvant dimethyl dioctadecyl ammonium/trehalose dibehenate (CAF01). Env binding in rabbit immune serum was determined using ELISAs based on gp120-IIIB protein. Neutralizing activity of IgG purified from rabbit immune sera was measured with the pseudovirus-TZMbl assay and a PBMC-based neutralization assay for selected experiments. It was initially established that gp140 trimers induce better antibody responses over gp120 monomers and that the adjuvant CAF01 was necessary for such strong responses. Gp140 trimers, based on HIV-1 variants from patients with bNAbs, were able to elicit both gp120IIIB specific IgG and NAbs to Tier 1 viruses of different subtypes. Potency of NAbs closely correlated with titers, and an gp120-binding IgG titer above a threshold of 100,000 was predictive of neutralization capability. Finally, peptide inhibition experiments showed that a large fraction of the neutralizing IgG was directed against the gp120 V3 region. Our results indicate that the strategy of reverse immunology based on selected Env sequences is promising when immunogens are delivered as stabilized trimers in CAF01 adjuvant and that the rabbit is a valuable model for HIV vaccine studies.

  17. Development of a chimeric Plasmodium berghei strain expressing the repeat region of the P. vivax circumsporozoite protein for in vivo evaluation of vaccine efficacy.

    Science.gov (United States)

    Espinosa, Diego A; Yadava, Anjali; Angov, Evelina; Maurizio, Paul L; Ockenhouse, Christian F; Zavala, Fidel

    2013-08-01

    The development of vaccine candidates against Plasmodium vivax-the most geographically widespread human malaria species-is challenged by technical difficulties, such as the lack of in vitro culture systems and availability of animal models. Chimeric rodent Plasmodium parasites are safe and useful tools for the preclinical evaluation of new vaccine formulations. We report the successful development and characterization of chimeric Plasmodium berghei parasites bearing the type I repeat region of P. vivax circumsporozoite protein (CSP). The P. berghei-P. vivax chimeric strain develops normally in mosquitoes and produces highly infectious sporozoites that produce patent infection in mice that are exposed to the bites of as few as 3 P. berghei-P. vivax-infected mosquitoes. Using this transgenic parasite, we demonstrate that monoclonal and polyclonal antibodies against P. vivax CSP strongly inhibit parasite infection and thus support the notion that these antibodies play an important role in protective immunity. The chimeric parasites we developed represent a robust model for evaluating protective immune responses against P. vivax vaccines based on CSP.

  18. A murine model of falciparum-malaria by in vivo selection of competent strains in non-myelodepleted mice engrafted with human erythrocytes.

    Directory of Open Access Journals (Sweden)

    Iñigo Angulo-Barturen

    Full Text Available To counter the global threat caused by Plasmodium falciparum malaria, new drugs and vaccines are urgently needed. However, there are no practical animal models because P. falciparum infects human erythrocytes almost exclusively. Here we describe a reliable falciparum murine model of malaria by generating strains of P. falciparum in vivo that can infect immunodeficient mice engrafted with human erythrocytes. We infected NOD(scid/beta2m-/- mice engrafted with human erythrocytes with P. falciparum obtained from in vitro cultures. After apparent clearance, we obtained isolates of P. falciparum able to grow in peripheral blood of engrafted NOD(scid/beta2m-/- mice. Of the isolates obtained, we expanded in vivo and established the isolate Pf3D7(0087/N9 as a reference strain for model development. Pf3D7(0087/N9 caused productive persistent infections in 100% of engrafted mice infected intravenously. The infection caused a relative anemia due to selective elimination of human erythrocytes by a mechanism dependent on parasite density in peripheral blood. Using this model, we implemented and validated a reproducible assay of antimalarial activity useful for drug discovery. Thus, our results demonstrate that P. falciparum contains clones able to grow reproducibly in mice engrafted with human erythrocytes without the use of myeloablative methods.

  19. Production of lactic acid from sucrose: strain selection, fermentation, and kinetic modeling.

    Science.gov (United States)

    Lunelli, Betânia H; Andrade, Rafael R; Atala, Daniel I P; Wolf Maciel, Maria Regina; Maugeri Filho, Francisco; Maciel Filho, Rubens

    2010-05-01

    Lactic acid is an important product arising from the anaerobic fermentation of sugars. It is used in the pharmaceutical, cosmetic, chemical, and food industries as well as for biodegradable polymer and green solvent production. In this work, several bacterial strains were isolated from industrial ethanol fermentation, and the most efficient strain for lactic acid production was selected. The fermentation was conducted in a batch system under anaerobic conditions for 50 h at a temperature of 34 degrees C, a pH value of 5.0, and an initial sucrose concentration of 12 g/L using diluted sugarcane molasses. Throughout the process, pulses of molasses were added in order to avoid the cell growth inhibition due to high sugar concentration as well as increased lactic acid concentrations. At the end of the fermentation, about 90% of sucrose was consumed to produce lactic acid and cells. A kinetic model has been developed to simulate the batch lactic acid fermentation results. The data obtained from the fermentation were used for determining the kinetic parameters of the model. The developed model for lactic acid production, growth cell, and sugar consumption simulates the experimental data well.

  20. Effect of strain rate and temperature on mechanical properties of selected building Polish steels

    Directory of Open Access Journals (Sweden)

    Moćko Wojciech

    2015-01-01

    Full Text Available Currently, the computer programs of CAD type are basic tool for designing of various structures under impact loading. Application of the numerical calculations allows to substantially reduce amount of time required for the design stage of such projects. However, the proper use of computer aided designing technique requires input data for numerical software including elastic-plastic models of structural materials. This work deals with the constitutive model developed by Rusinek and Klepaczko (RK applied for the modelling of mechanical behaviour of selected grades structural St0S, St3SX, 18GS and 34GS steels and presents here results of experimental and empirical analyses to describe dynamic elastic-plastic behaviours of tested materials at wide range of temperature. In order to calibrate the RK constitutive model, series of compression tests at wide range of strain rates, including static, quasi-static and dynamic investigations at lowered, room and elevated temperatures, were carried out using two testing stands: servo-hydraulic machine and split Hopkinson bar. The results were analysed to determine influence of temperature and strain rate on visco-plastic response of tested steels, and show good correlation with experimental data.

  1. Estimating the costs of the vaccine supply chain and service delivery for selected districts in Kenya and Tanzania.

    Science.gov (United States)

    Mvundura, Mercy; Lorenson, Kristina; Chweya, Amos; Kigadye, Rosemary; Bartholomew, Kathryn; Makame, Mohammed; Lennon, T Patrick; Mwangi, Steven; Kirika, Lydia; Kamau, Peter; Otieno, Abner; Murunga, Peninah; Omurwa, Tom; Dafrossa, Lyimo; Kristensen, Debra

    2015-05-28

    Having data on the costs of the immunization system can provide decision-makers with information to benchmark the costs when evaluating the impact of new technologies or programmatic innovations. This paper estimated the supply chain and immunization service delivery costs and cost per dose in selected districts in Kenya and Tanzania. We also present operational data describing the supply chain and service delivery points (SDPs). To estimate the supply chain costs, we collected resource-use data for the cold chain, distribution system, and health worker time and per diems paid. We also estimated the service delivery costs, which included the time cost of health workers to provide immunization services, and per diems and transport costs for outreach sessions. Data on the annual quantities of vaccines distributed to each facility, and the occurrence and duration of stockouts were collected from stock registers. These data were collected from the national store, 2 regional and 4 district stores, and 12 SDPs in each country for 2012. Cost per dose for the supply chain and immunization service delivery were estimated. The average annual costs per dose at the SDPs were $0.34 (standard deviation (s.d.) $0.18) for Kenya when including only the vaccine supply chain costs, and $1.33 (s.d. $0.82) when including immunization service delivery costs. In Tanzania, these costs were $0.67 (s.d. $0.35) and $2.82 (s.d. $1.64), respectively. Both countries experienced vaccine stockouts in 2012, bacillus Calmette-Guérin vaccine being more likely to be stocked out in Kenya, and oral poliovirus vaccine in Tanzania. When stockouts happened, they usually lasted for at least one month. Tanzania made investments in 2011 in preparation for planned vaccine introductions, and their supply chain cost per dose is expected to decline with the new vaccine introductions. Immunization service delivery costs are a significant portion of the total costs at the SDPs. Copyright © 2015 Elsevier Ltd. All

  2. Selection of Yeast Strains for Tequila Fermentation Based on Growth Dynamics in Combined Fructose and Ethanol Media.

    Science.gov (United States)

    Aldrete-Tapia, J A; Miranda-Castilleja, D E; Arvizu-Medrano, S M; Hernández-Iturriaga, M

    2018-02-01

    The high concentration of fructose in agave juice has been associated with reduced ethanol tolerance of commercial yeasts used for tequila production and low fermentation yields. The selection of autochthonous strains, which are better adapted to agave juice, could improve the process. In this study, a 2-step selection process of yeasts isolated from spontaneous fermentations for tequila production was carried out based on analysis of the growth dynamics in combined conditions of high fructose and ethanol. First, yeast isolates (605) were screened to identify strains tolerant to high fructose (20%) and to ethanol (10%), yielding 89 isolates able to grow in both conditions. From the 89 isolates, the growth curves under 8 treatments of combined fructose (from 20% to 5%) and ethanol (from 0% to 10%) were obtained, and the kinetic parameters were analyzed with principal component analysis and k-means clustering. The resulting yeast strain groups corresponded to the fast, medium and slow growers. A second clustering of only the fast growers led to the selection of 3 Saccharomyces strains (199, 230, 231) that were able to grow rapidly in 4 out of the 8 conditions evaluated. This methodology differentiated strains phenotypically and could be further used for strain selection in other processes. A method to select yeast strains for fermentation taking into account the natural differences of yeast isolates. This methodology is based on the cell exposition to combinations of sugar and ethanol, which are the most important stress factors in fermentation. This strategy will help to identify the most tolerant strain that could improve ethanol yield and reduce fermentation time. © 2018 Institute of Food Technologists®.

  3. Characterization of three porcine reproductive and respiratory syndrome virus isolates from a single swine farm bearing strong homology to a vaccine strain.

    Science.gov (United States)

    Jiang, Yi-feng; Xia, Tian-qi; Zhou, Yan-jun; Yu, Ling-xue; Yang, Shen; Huang, Qin-feng; Li, Li-wei; Gao, Fei; Qu, Ze-hui; Tong, Wu; Tong, Guang-zhi

    2015-09-30

    Three porcine reproductive and respiratory syndrome viruses (PRRSV), NT1, NT2, and NT3, were isolated from three dying piglets from a single pig farm in Jiangsu Province, China. Whole genome sequencing revealed that the three isolates share the highest homology with JXA1-P80, an attenuated vaccine strain developed by serial passage of highly pathogenic PRRSV JXA1 in MARC-145 cells. More than ten amino acids residues in ORF1a, ORF1b, GP4, and GP5 that were thought to be unique to JXA1 attenuated on MARC-145 cells were each found in the corresponding locations of NT1, NT2, and NT3. In virulence assays, piglets infected with NT1, NT2, or NT3 exhibited clinical signs of disease, including high fever, anorexia, and respiratory distress, leading to the death of the majority of the piglets within two weeks. Collectively, these data indicate that NT1, NT2, and NT3 are highly pathogenic PRRSVs and they are likely to be revertants of the vaccine strain JXA1-P80. Copyright © 2015 Elsevier B.V. All rights reserved.

  4. Whole genome characterization of a novel porcine reproductive and respiratory syndrome virus 1 isolate: Genetic evidence for recombination between Amervac vaccine and circulating strains in mainland China.

    Science.gov (United States)

    Chen, Nanhua; Liu, Qiaorong; Qiao, Mingming; Deng, Xiaoyu; Chen, Xizhao; Sun, Ming

    2017-10-01

    Genotype 1 porcine reproductive and respiratory syndrome virus (PRRSV 1) have been continuously isolated in China in recent years. Complete genome sequences of these isolates are important to investigate the prevalence and evolution of Chinese PRRSV 1. Herein, we describe the isolation of a novel PRRSV 1 isolate, denominated HLJB1, in the Heilongjiang province of China. Complete genome sequencing of HLJB1 showed that it shares 90.66% and 58.21% nucleotide identities with PRRSV 1 and 2 prototypic strains Lelystad virus and ATCC VR-2332, respectively. HLJB1 has a unique 5-amino-acid insertion in nsp2, which has never been described in other PRRSV 1 isolates. Whole genome-based phylogenetic analysis revealed that all Chinese PRRSV 1 isolates are clustered in pan-European subtype 1 and can be divided into four subgroups. HLJB1 resides in the subgroup of BJEU06-1-like isolates but is also closely related to the Amervac-like isolates. Additionally, recombination analyses suggested that HLJB1 is a recombinant from the Amervac vaccine and the BJEU06-1 isolate. To our best knowledge, our results provide the first genetic evidence for recombination between Amervac vaccine and circulating strains. These findings are also beneficial for studying the origin and evolution of PRRSV 1 in China. Copyright © 2017. Published by Elsevier B.V.

  5. Hepatitis B vaccination coverage and the determinants of vaccination among health care workers in selected health facilities in Lusaka district, Zambia: an exploratory study

    OpenAIRE

    Mungandi, Namwaka; Makasa, Mpundu; Musonda, Patrick

    2017-01-01

    Background Hepatitis B is a viral infection of the liver and causes both acute and chronic disease. It is transmitted through contact with an infected person’s bodily fluids. It is an occupational hazard for healthcare workers and can be prevented by the administration of a vaccine. It is recommended that healthcare workers be vaccinated against vaccine preventable diseases including hepatitis B. The study objective was to determine the prevalence and determinants of hepatitis B vaccination a...

  6. Algal bioremediation of waste waters from land-based aquaculture using ulva: selecting target species and strains.

    Directory of Open Access Journals (Sweden)

    Rebecca J Lawton

    Full Text Available The optimised reduction of dissolved nutrient loads in aquaculture effluents through bioremediation requires selection of appropriate algal species and strains. The objective of the current study was to identify target species and strains from the macroalgal genus Ulva for bioremediation of land-based aquaculture facilities in Eastern Australia. We surveyed land-based aquaculture facilities and natural coastal environments across three geographic locations in Eastern Australia to determine which species of Ulva occur naturally in this region and conducted growth trials at three temperature treatments on a subset of samples from each location to determine whether local strains had superior performance under local environmental conditions. DNA barcoding using the markers ITS and tufA identified six species of Ulva, with U. ohnoi being the most common blade species and U. sp. 3 the most common filamentous species. Both species occurred at multiple land-based aquaculture facilities in Townsville and Brisbane and multiple strains of each species grew well in culture. Specific growth rates of U. ohnoi and U. sp. 3 were high (over 9% and 15% day(-1 respectively across temperature treatments. Within species, strains of U. ohnoi had higher growth in temperatures corresponding to local conditions, suggesting that strains may be locally adapted. However, across all temperature treatments Townsville strains had the highest growth rates (11.2-20.4% day(-1 and Sydney strains had the lowest growth rates (2.5-8.3% day(-1. We also found significant differences in growth between strains of U. ohnoi collected from the same geographic location, highlighting the potential to isolate and cultivate fast growing strains. In contrast, there was no clearly identifiable competitive strain of filamentous Ulva, with multiple species and strains having variable performance. The fast growth rates and broad geographical distribution of U. ohnoi make this an ideal species to

  7. Cloning of the genome of a goose parvovirus vaccine strain SYG61v and rescue of infectious virions from recombinant plasmid in embryonated goose eggs.

    Science.gov (United States)

    Wang, Jianye; Duan, Jinkun; Meng, Xia; Gong, Jiansen; Jiang, Zhiwei; Zhu, Guoqiang

    2014-05-01

    The SYG61v is an attenuated goose parvovirus (GPV) that has been used as a vaccine strain in China. The genome of SYG61v was sequenced to attempt to identify the genetic basis for the attenuation of this strain. The entire genome consists of 5102 nucleotides (nts), with four nt deletions compared to that of virulent strain B. The inverted terminal repeats (ITR) are 442 nts in length, of which 360 nts form a stem region, and 43 nts constitute the bubble region. Although mutations were observed throughout the ITR, no mismatch was found in the stem. Alignment with other pathogenic GPV strains (B, 82-0321, 06-0329, and YZ99-5) indicated that there are 10 and 11 amino acid mutations in the Rep1 and VP1 proteins of SYG61v, respectively. The complete genome of SYG61v was cloned into the pBluescript II vector and an infectious plasmid pSYG61v was generated. Infectious progeny virus was successfully rescued through transfection of the plasmid pSYG61v in embryonated goose eggs and yielded viral titers similar to its parental virus, as evaluated by ELD50. Copyright © 2014 Elsevier B.V. All rights reserved.

  8. Recombinant HA1 produced in E. coli forms functional oligomers and generates strain-specific SRID potency antibodies for pandemic influenza vaccines.

    Science.gov (United States)

    Khurana, Surender; Larkin, Christopher; Verma, Swati; Joshi, Manju B; Fontana, Juan; Steven, Alasdair C; King, Lisa R; Manischewitz, Jody; McCormick, William; Gupta, Rajesh K; Golding, Hana

    2011-08-05

    Vaccine production and initiation of mass vaccination is a key factor in rapid response to new influenza pandemic. During the 2009-2010 H1N1 pandemic, several bottlenecks were identified, including the delayed availability of vaccine potency reagents. Currently, antisera for the single-radial immunodiffusion (SRID) potency assay are generated in sheep immunized repeatedly with HA released and purified after bromelain-treatment of influenza virus grown in eggs. This approach was a major bottleneck for pandemic H1N1 (H1N1pdm09) potency reagent development in 2009. Alternative approaches are needed to make HA immunogens for generation of SRID reagents in the shortest possible time. In this study, we found that properly folded recombinant HA1 globular domain (rHA1) from several type A viruses including H1N1pdm09 and two H5N1 viruses could be produced efficiently using a bacterial expression system and subsequent purification. The rHA1 proteins were shown to form functional oligomers of trimers, similar to virus derived HA, and elicited high titer of neutralizing antibodies in rabbits and sheep. Importantly, the immune sera formed precipitation rings with reference antigens in the SRID assay in a dose-dependent manner. The HA contents in multiple H1N1 vaccine products from different manufacturers (and in several lots) as determined with the rHA1-generated sheep sera were similar to the values obtained with a traditionally generated sheep serum from NIBSC. We conclude that bacterially expressed recombinant HA1 proteins can be produced rapidly and used to generate SRID potency reagents shortly after new influenza strains with pandemic potential are identified. Published by Elsevier Ltd.

  9. Screening of probiotic activities of forty-seven strains of Lactobacillus spp. by in vitro techniques and evaluation of the colonization ability of five selected strains in humans.

    Science.gov (United States)

    Jacobsen, C N; Rosenfeldt Nielsen, V; Hayford, A E; Møller, P L; Michaelsen, K F; Paerregaard, A; Sandström, B; Tvede, M; Jakobsen, M

    1999-11-01

    The probiotic potential of 47 selected strains of Lactobacillus spp. was investigated. The strains were examined for resistance to pH 2.5 and 0.3% oxgall, adhesion to Caco-2 cells, and antimicrobial activities against enteric pathogenic bacteria in model systems. From the results obtained in vitro, five strains, Lactobacillus rhamnosus 19070-2, L. reuteri DSM 12246, L. rhamnosus LGG, L. delbrueckii subsp. lactis CHCC 2329, and L. casei subsp. alactus CHCC 3137, were selected for in vivo studies. The daily consumption by 12 healthy volunteers of two doses of 10(10) freeze-dried bacteria of the selected strains for 18 days was followed by a washout period of 17 days. Fecal samples were taken at days 0 and 18 and during the washout period at days 5 and 11. Lactobacillus isolates were initially identified by API 50CHL and internal transcribed spacer PCR, and their identities were confirmed by restriction enzyme analysis in combination with pulsed-field gel electrophoresis. Among the tested strains, L. rhamnosus 19070-2, L. reuteri DSM 12246, and L. rhamnosus LGG were identified most frequently in fecal samples; they were found in 10, 8, and 7 of the 12 samples tested during the intervention period, respectively, whereas reisolations were less frequent in the washout period. The bacteria were reisolated in concentrations from 10(5) to 10(8) cells/g of feces. Survival and reisolation of the bacteria in vivo appeared to be linked to pH tolerance, adhesion, and antimicrobial properties in vitro.

  10. In vitro screening of selected probiotic properties of Lactobacillus strains isolated from traditional fermented cabbage and cucumber.

    Science.gov (United States)

    Zielińska, Dorota; Rzepkowska, Anna; Radawska, Anna; Zieliński, Konrad

    2015-02-01

    Most important during probiotic selection are gastric acid and bile tolerance, the adhesion to the luminal epithelium to colonize the lower gastrointestinal tract of a human and safety for human consumption. The aim of this study was to evaluate the selected probiotic in vitro properties of Lactobacillus spp. Strains isolated from traditional fermented food. A total 38 strains were isolated from the pickled samples and 14 were identified as Lactobacillus spp. The survival of almost all strains after incubation at pH 2.5 did not change markedly, and remained at above 90 % (10(9) CFU/mL). The strains also exhibited a high survival rate at pH 3.5 (>90 %), whereas pH 1.5 all were died. Just four strains could survive 90 min. at pH 1.5 (survival rates of 81-94 % after 24 h, whereas after incubation in 2 and 4 % bile salt solution it was 59-94 %. All tested strains showed very good and good resistance to 0.4 % phenol addition, however only Lb. johnsonii K4 was able to multiply. The hydrophobic nature of the cell surface of the tested strains was moderated recording hydrophobicity of Lb. johnsonii K4 and Lb. rhamnosus K3 above 60 %. Safety evaluation excluded four of tested strains as candidate probiotics, according to antibiotic resistance patterns and certain metabolic activities. On the basis on the results 10 of the selected Lactobacillus strains are safe and can survive under gastrointestinal conditions, which requires them to future in vitro and in vivo probiotic studies.

  11. Strain selection, biomass to biofuel conversion, and resource colocation have strong impacts on the economic performance of algae cultivation sites

    Directory of Open Access Journals (Sweden)

    Erik R. Venteris

    2014-09-01

    Full Text Available Decisions involving strain selection, biomass to biofuel technology, and the location of cultivation facilities can strongly influence the economic viability of an algae-based biofuel enterprise. We summarize our past results in a new analysis to explore the relative economic impact of these design choices. Our growth model is used to predict average biomass production for two saline strains (Nannocloropsis salina, Arthrospira sp., one fresh to brackish strain (Chlorella sp., DOE strain 1412, and one freshwater strain (order Sphaeropleales. Biomass to biofuel conversion is compared between lipid extraction (LE and hydrothermal liquefaction (HTL technologies. National-scale models of water, CO2 (as flue gas, land acquisition, site leveling, construction of connecting roads, and transport of HTL oil to existing refineries are used in conjunction with estimates of fuel value (from HTL to prioritize and select from 88,692 unit farms (UF, 405 ha in pond area, a number sufficient to produce 136E+9 L yr-1 of renewable diesel (36 billion gallons yr-1. Strain selection and choice of conversion technology have large economic impacts, with differences between combinations of strains and biomass to biofuel technologies being up to $10 million dollars yr-1 UF-1. Results based on the most productive strain, HTL-based fuel conversion, and resource costs show that the economic potential between geographic locations within the selection can differ by up to $4 million yr-1 UF-1, with 1.8 BGY of production possible from the most cost-effective sites. The local spatial variability in site rank is extreme, with very high and low sites within 10s of km of each other. Colocation with flue gas sources has a strong influence on rank, but the most costly resource component varies from site to site. The highest rank UFs are located predominantly in Florida and Texas, but most states south of 37°N latitude contain promising locations.

  12. Effect of strain, substrate surface and growth rate on B-doping in selectively grown SiGe layers

    International Nuclear Information System (INIS)

    Ghandi, R.; Kolahdouz, M.; Hallstedt, J.; Wise, R.; Wejtmans, Hans; Radamson, H.H.

    2008-01-01

    In this work, the role of strain and growth rate on boron incorporation in selective epitaxial growth (SEG) of B-doped Si 1-x Ge x (x = 0.15-0.25) layers in recessed or unprocessed (elevated) openings for source/drain applications in CMOS has been studied. A focus has been made on the strain distribution and B incorporation in SEG of SiGe layers

  13. Effect of strain, substrate surface and growth rate on B-doping in selectively grown SiGe layers

    Energy Technology Data Exchange (ETDEWEB)

    Ghandi, R. [School of Information and Communication Technology, KTH (Royal Institute of Technology), Isafjordsg. 22-26, Electrum 229, 16640 Kista (Sweden)], E-mail: ghandi@kth.se; Kolahdouz, M.; Hallstedt, J. [School of Information and Communication Technology, KTH (Royal Institute of Technology), Isafjordsg. 22-26, Electrum 229, 16640 Kista (Sweden); Wise, R.; Wejtmans, Hans [Texas Instrument, 13121 TI Boulevard, Dallas, Tx 75243 (United States); Radamson, H.H. [School of Information and Communication Technology, KTH (Royal Institute of Technology), Isafjordsg. 22-26, Electrum 229, 16640 Kista (Sweden)

    2008-11-03

    In this work, the role of strain and growth rate on boron incorporation in selective epitaxial growth (SEG) of B-doped Si{sub 1-x}Ge{sub x} (x = 0.15-0.25) layers in recessed or unprocessed (elevated) openings for source/drain applications in CMOS has been studied. A focus has been made on the strain distribution and B incorporation in SEG of SiGe layers.

  14. The impact of search engine selection and sorting criteria on vaccination beliefs and attitudes: two experiments manipulating Google output.

    Science.gov (United States)

    Allam, Ahmed; Schulz, Peter Johannes; Nakamoto, Kent

    2014-04-02

    During the past 2 decades, the Internet has evolved to become a necessity in our daily lives. The selection and sorting algorithms of search engines exert tremendous influence over the global spread of information and other communication processes. This study is concerned with demonstrating the influence of selection and sorting/ranking criteria operating in search engines on users' knowledge, beliefs, and attitudes of websites about vaccination. In particular, it is to compare the effects of search engines that deliver websites emphasizing on the pro side of vaccination with those focusing on the con side and with normal Google as a control group. We conducted 2 online experiments using manipulated search engines. A pilot study was to verify the existence of dangerous health literacy in connection with searching and using health information on the Internet by exploring the effect of 2 manipulated search engines that yielded either pro or con vaccination sites only, with a group receiving normal Google as control. A pre-post test design was used; participants were American marketing students enrolled in a study-abroad program in Lugano, Switzerland. The second experiment manipulated the search engine by applying different ratios of con versus pro vaccination webpages displayed in the search results. Participants were recruited from Amazon's Mechanical Turk platform where it was published as a human intelligence task (HIT). Both experiments showed knowledge highest in the group offered only pro vaccination sites (Z=-2.088, P=.03; Kruskal-Wallis H test [H₅]=11.30, P=.04). They acknowledged the importance/benefits (Z=-2.326, P=.02; H5=11.34, P=.04) and effectiveness (Z=-2.230, P=.03) of vaccination more, whereas groups offered antivaccination sites only showed increased concern about effects (Z=-2.582, P=.01; H₅=16.88, P=.005) and harmful health outcomes (Z=-2.200, P=.02) of vaccination. Normal Google users perceived information quality to be positive despite a

  15. Genome sequence of Corynebacterium pseudotuberculosis biovar equi strain 258 and prediction of antigenic targets to improve biotechnological vaccine production

    DEFF Research Database (Denmark)

    Soares, Siomar C; Trost, Eva; Ramos, Rommel T J

    2013-01-01

    Corynebacterium pseudotuberculosis is the causative agent of several veterinary diseases in a broad range of economically important hosts, which can vary from caseous lymphadenitis in sheep and goats (biovar ovis) to ulcerative lymphangitis in cattle and horses (biovar equi). Existing vaccines ag...

  16. Protection against California 2002 NDV strain afforded by adenovirus vectored vaccine expressing Fusion or Hemagglutination-neuraminidase genes

    Science.gov (United States)

    Vectored vaccines expressing the combination of the hemagglutinin-neuraminidase (HN) and fusion (F) genes generally have better clinical protection against Newcastle disease virus (NDV) than when either the F and HN genes are expressed alone. Interestingly, the protection induced by F is usually bet...

  17. Selected Lactobacillus strains isolated from sugary and milk kefir reduce Salmonella infection of epithelial cells in vitro.

    Science.gov (United States)

    Zavala, L; Golowczyc, M A; van Hoorde, K; Medrano, M; Huys, G; Vandamme, P; Abraham, A G

    2016-09-01

    The isolation of potentially probiotic strains and the subsequent study of their properties are very important steps to gain insight in the health benefits ascribed to sugary and milk kefir. The aim of the present study was to characterise fifteen Lactobacillus strains isolated from these beverages by determining some surface properties and their ability to antagonise enterocyte cell damage after Salmonella infection in vitro. Lactobacillus surface properties were determined by hydrophobicity, autoaggregation, and coaggregation assays with Salmonella. In addition, lactobacilli adhesion to Caco-2/TC-7 cells and the effect on Salmonella invasion were evaluated. Finally, the disassembly of F-actin cytoskeleton on intestinal epithelial cells was assayed in vitro when Salmonella infection was performed in the presence of selected Lactobacillus strains. Ten out of the 15 strains showed a high adhesion capacity to Caco-2/TC-7 cells. Most of the strains were hydrophilic and non-autoaggregating. Strains isolated from sugary kefir were non-coaggregating with Salmonella, while strains Lactobacillus paracasei CIDCA 83120, 83121, 83123, 83124, 8339, 83102 isolated from milk kefir were able to coaggregate after 1 h. L. paracasei CIDCA 8339 and Lactobacillus kefiri CIDCA 83102 were able to diminish Salmonella invasion to the enterocytes. An antagonistic effect on cytoskeleton disruption elicited by the pathogen was also demonstrated. Our results suggest that both strains isolated from milk kefir could be considered as appropriate probiotic candidates.

  18. Biotransformation of albendazole and activities of selected detoxification enzymes in Haemonchus contortus strains susceptible and resistant to anthelmintics.

    Science.gov (United States)

    Vokřál, Ivan; Jirásko, Robert; Stuchlíková, Lucie; Bártíková, Hana; Szotáková, Barbora; Lamka, Jiří; Várady, Marián; Skálová, Lenka

    2013-09-23

    The increased activity of drug-metabolizing enzymes can protect helminths against the toxic effect of anthelmintics. The aim of this study was to compare the metabolism of the anthelmintic drug albendazole (ABZ) and the activities of selected biotransformation and antioxidant enzymes in three different strains of Haemonchus contortus: the ISE strain (susceptible to common anthelmintics), the BR strain (resistant to benzimidazole anthelmintics) and the WR strain (multi-resistant). H. contortus adults were collected from the abomasum of experimentally infected lambs. In vitro (subcellular fractions of H. contortus homogenate) as well as ex vivo (living nematodes cultivated in flasks with medium) experiments were performed. HPLC with spectrofluorimetric and mass-spectrometric detection was used in the analysis of ABZ metabolites. The in vitro activities of oxidation/antioxidation and conjugation enzymes toward model substrates were also assayed. The in vitro data showed significant differences between the susceptible (ISE) and resistant (BR, WR) strains regarding the activities of peroxidases, catalase and UDP-glucosyltransferases. S-oxidation of ABZ was significantly lower in BR than in the ISE strain. Ex vivo, four ABZ metabolites were identified: ABZ sulphoxide and three ABZ glucosides. In the resistant strains BR and WR, the ex vivo formation of all ABZ glucosides was significantly higher than in the susceptible ISE strain. The altered activities of certain detoxifying enzymes might partly protect the parasites against the toxic effect of the drugs as well as contribute to drug-resistance in these parasites. Copyright © 2013 Elsevier B.V. All rights reserved.

  19. Human rotavirus vaccine Rotarix™ provides protection against diverse circulating rotavirus strains in African infants: a randomized controlled trial.

    Science.gov (United States)

    Steele, Andrew Duncan; Neuzil, Kathleen M; Cunliffe, Nigel A; Madhi, Shabir A; Bos, Pieter; Ngwira, Bagrey; Witte, Desiree; Todd, Stacy; Louw, Cheryl; Kirsten, Mari; Aspinall, Sanet; Van Doorn, Leen Jan; Bouckenooghe, Alain; Suryakiran, Pemmaraju V; Han, Htay Htay

    2012-09-13

    Rotaviruses are the most important cause of severe acute gastroenteritis worldwide in children rotavirus vaccine Rotarix™ significantly reduced severe rotavirus gastroenteritis episodes in a Phase III clinical trial conducted in infants in South Africa and Malawi. This paper examines rotavirus vaccine efficacy in preventing severe rotavirus gastroenteritis, during infancy, caused by the various G and P rotavirus types encountered during the first rotavirus-season. Healthy infants aged 5-10 weeks were enrolled and randomized into three groups to receive either two (10 and 14 weeks) or three doses of Rotarix™ (together forming the pooled Rotarix™ group) or three doses of placebo at a 6,10,14-week schedule. Weekly home visits were conducted to identify gastroenteritis episodes. Rotaviruses were detected by ELISA and genotyped by RT-PCR and nucleotide sequencing. The percentage of infants with severe rotavirus gastroenteritis caused by the circulating G and P types from 2 weeks post-last dose until one year of age and the corresponding vaccine efficacy was calculated with 95% CI. Overall, 4939 infants were vaccinated and 4417 (pooled Rotarix™ = 2974; placebo = 1443) were included in the per protocol efficacy cohort. G1 wild-type was detected in 23 (1.6%) severe rotavirus gastroenteritis episodes from the placebo group. This was followed in order of detection by G12 (15 [1%] in placebo) and G8 types (15 [1%] in placebo). Vaccine efficacy against G1 wild-type, G12 and G8 types were 64.1% (95% CI: 29.9%; 82%), 51.5% (95% CI:-6.5%; 77.9%) and 64.4% (95% CI: 17.1%; 85.2%), respectively. Genotype P[8] was the predominant circulating P type and was detected in 38 (2.6%) severe rotavirus gastroenteritis cases in placebo group. The remaining circulating P types comprised of P[4] (20 [1.4%] in placebo) and P[6] (13 [0.9%] in placebo). Vaccine efficacy against P[8] was 59.1% (95% CI: 32.8%; 75.3%), P[4] was 70.9% (95% CI: 37.5%; 87.0%) and P[6] was 55.2% (95% CI: -6

  20. Drop of egg production in chickens by experimental infection with an avian metapneumovirus strain PLE8T1 derived from swollen head syndrome and the application to evaluate vaccine.

    Science.gov (United States)

    Sugiyama, Miki; Koimaru, Hiroyuki; Shiba, Masahiro; Ono, Eriko; Nagata, Tadashi; Ito, Toshihiro

    2006-08-01

    Decreases in egg production and increased incidence of abnormal eggs due to malformation of egg shells were observed in specific pathogen free (SPF) 173-day-old laying hens inoculated intravenously with an avian metapneumovirus (aMPV) strain PLE8T1. This strain was derived from an isolate from broiler birds exhibiting swollen head syndrome (SHS). Some SPF birds inoculated with the virus showed, slight diarrhea without any respiratory symptoms. Thus, the PLE8T1 strain was used as a challenge virus to evaluate efficacy of aMPV vaccines. SPF chickens which received a live attenuated aMPV vaccine (NEMOVAC; Merial) at 7 or 77 days old and an inactivated aMPV vaccine (OVO-4; Merial) at 105 days old were protected against poor egg production caused by the challenge with the PLE8T1 strain. Thus, aMPV, the PLE8T1 strain passaged 22 times after isolation, from birds exhibiting SHS, could induce a drop in egg production in laying hens accompanied by malformation of egg shells. It was suggested that this challenge system could be applied to evaluate the efficacy of aMPV vaccine.

  1. Rotavirus vaccines: an overview.

    OpenAIRE

    Midthun, K; Kapikian, A Z

    1996-01-01

    Rotavirus vaccine development has focused on the delivery of live attenuated rotavirus strains by the oral route. The initial "Jennerian" approach involving bovine (RIT4237, WC3) or rhesus (RRV) rotavirus vaccine candidates showed that these vaccines were safe, well tolerated, and immunogenic but induced highly variable rates of protection against rotavirus diarrhea. The goal of a rotavirus vaccine is to prevent severe illness that can lead to dehydration in infants and young children in both...

  2. Determination of yeast killer activity in fermenting sugarcane juice using selected ethanol-making strains

    Directory of Open Access Journals (Sweden)

    Sandra Regina Ceccato-Antonini

    2004-03-01

    Full Text Available Twenty-four yeasts out of 342 isolated from the fermentative process showed killer activity and three of them were selected for the fermentative efficiency evaluation in batch system with cell recycle, flask and fermentor experiments. The selected three killer strains did not present similar results to those of pressed (baking yeast concerning ethanol (0.07-0.18; 0.12-0.20; 0.10-0.13; 0.22-0.25 g/g, respectively and biomass (0.19-0.26; 0.33-0.39; 0.13-0.27; 0.47-0.61 g/g, respectively yields and fermentative efficiency (12.3-36.3; 21.0-40.0; 19.3-26.3; 47.6-54.0 %, respectively in sugarcane juice, in flasks. In fermentor, similar behaviour was observed. However, the selected strains showed high cellular viability and killer activity (using cell-free filtrate along the fermentative cycles, in spite of the unfavourable conditions of the medium, like high pH variation of the medium (from 5.5-6.0 to 3.0-4.0, low aeration and higher temperature (30º C, which were not the ideal ones for the production/activity of killer toxins. A Pichia strain (CCA 510 showed the best results among the killer yeasts tested, exhibiting a killer activity against 92% of isolated fermentative yeasts of the process and against the pressed (baking ferment. It also demonstrated killer activity (using crude toxin preparation at higher temperatures (38ºC and low pH (4.0 after 72 hours of incubation, under proliferative and non-proliferative conditions. The results indicated that the killer activity should be a characteristic to be looked for in the strain selection for ethanolic fermentation, beside other important productivity-based characteristics, since it assure the permanence of the selected strain during the process.A atividade 'killer' poderia garantir às leveduras fermentativas uma vantagem competitiva sobre outras linhagens durante a fermentação etanólica, no entanto, pouco se sabe sobre o papel do sistema 'killer' nesse tipo de fermentação alcoólica. A sele

  3. Generation of a novel live rabies vaccine strain with a high level of safety by introducing attenuating mutations in the nucleoprotein and glycoprotein.

    Science.gov (United States)

    Nakagawa, Keisuke; Nakagawa, Kento; Omatsu, Tsutomu; Katayama, Yukie; Oba, Mami; Mitake, Hiromichi; Okada, Kazuma; Yamaoka, Satoko; Takashima, Yasuhiro; Masatani, Tatsunori; Okadera, Kota; Ito, Naoto; Mizutani, Tetsuya; Sugiyama, Makoto

    2017-10-09

    The current live rabies vaccine SAG2 is attenuated by only one mutation (Arg-to-Glu) at position 333 in the glycoprotein (G333). This fact generates a potential risk of the emergence of a pathogenic revertant by a back mutation at this position during viral propagation in the body. To circumvent this risk, it is desirable to generate a live vaccine strain highly and stably attenuated by multiple mutations. However, the information on attenuating mutations other than that at G333 is very limited. We previously reported that amino acids at positions 273 and 394 in the nucleoprotein (N273/394) (Leu and His, respectively) of fixed rabies virus Ni-CE are responsible for the attenuated phenotype by enhancing interferon (IFN)/chemokine gene expressions in infected neural cells. In this study, we found that amino acid substitutions at N273/394 (Phe-to-Leu and Tyr-to-His, respectively) attenuated the pathogenicity of the oral live vaccine ERA, which has a virulent-type Arg at G333. Then we generated ERA-N273/394-G333 attenuated by the combination of the above attenuating mutations at G333 and N273/394, and checked its safety. Similar to the ERA-G333, which is attenuated by only the mutation at G333, ERA-N273/394-G333 did not cause any symptoms in adult mice after intracerebral inoculation, indicating a low level of residual pathogenicity of ERA-N273/394-G333. Further examination revealed that infection with ERA-N273/394-G333 induces IFN-β and CXCL10 mRNA expressions more strongly than ERA-G333 infection in a neuroblastoma cell line. Importantly, we found that the ERA-N273/394-G333 stain has a lower risk for emergence of a pathogenic revertant than does the ERA-G333. These results indicate that ERA-N273/394-G333 has a potential to be a promising candidate for a live rabies vaccine strain with a high level of safety. Copyright © 2017 Elsevier Ltd. All rights reserved.

  4. Entirely Carbohydrate-Based Vaccines: An Emerging Field for Specific and Selective Immune Responses

    Directory of Open Access Journals (Sweden)

    Sharmeen Nishat

    2016-05-01

    Full Text Available Carbohydrates are regarded as promising targets for vaccine development against infectious disease because cell surface glycans on many infectious agents are attributed to playing an important role in pathogenesis. In addition, oncogenic transformation of normal cells, in many cases, is associated with aberrant glycosylation of the cell surface glycan generating tumor associated carbohydrate antigens (TACAs. Technological advances in glycobiology have added a new dimension to immunotherapy when considering carbohydrates as key targets in developing safe and effective vaccines to combat cancer, bacterial infections, viral infections, etc. Many consider effective vaccines induce T-cell dependent immunity with satisfactory levels of immunological memory that preclude recurrence. Unfortunately, carbohydrates alone are poorly immunogenic as they do not bind strongly to the MHCII complex and thus fail to elicit T-cell immunity. To increase immunogenicity, carbohydrates have been conjugated to carrier proteins, which sometimes can impede carbohydrate specific immunity as peptide-based immune responses can negate antibodies directed at the targeted carbohydrate antigens. To overcome many challenges in using carbohydrate-based vaccine design and development approaches targeting cancer and other diseases, zwitterionic polysaccharides (ZPSs, isolated from the capsule of commensal anaerobic bacteria, will be discussed as promising carriers of carbohydrate antigens to achieve desired immunological responses.

  5. Prescreening of Nicotine Hapten Linkers in Vitro To Select Hapten-Conjugate Vaccine Candidates for Pharmacokinetic Evaluation in Vivo.

    Science.gov (United States)

    Arutla, Viswanath; Leal, Joseph; Liu, Xiaowei; Sokalingam, Sriram; Raleigh, Michael; Adaralegbe, Adejimi; Liu, Li; Pentel, Paul R; Hecht, Sidney M; Chang, Yung

    2017-05-08

    Since the demonstration of nicotine vaccines as a possible therapeutic intervention for the effects of tobacco smoke, extensive effort has been made to enhance nicotine specific immunity. Linker modifications of nicotine haptens have been a focal point for improving the immunogenicity of nicotine, in which the evaluation of these modifications usually relies on in vivo animal models, such as mice, rats or nonhuman primates. Here, we present two in vitro screening strategies to estimate and predict the immunogenic potential of our newly designed nicotine haptens. One utilizes a competition enzyme-linked immunoabsorbent assay (ELISA) to profile the interactions of nicotine haptens or hapten-protein conjugates with nicotine specific antibodies, both polyclonal and monoclonal. Another relies on computational modeling of the interactions between haptens and amino acid residues near the conjugation site of the carrier protein to infer linker-carrier protein conjugation effect on antinicotine antibody response. Using these two in vitro methods, we ranked the haptens with different linkers for their potential as viable vaccine candidates. The ELISA-based hapten ranking was in an agreement with the results obtained by in vivo nicotine pharmacokinetic analysis. A correlation was found between the average binding affinity (IC 50 ) of the haptens to an anti-Nic monoclonal antibody and the average brain nicotine concentration in the immunized mice. The computational modeling of hapten and carrier protein interactions helps exclude conjugates with strong linker-carrier conjugation effects and low in vivo efficacy. The simplicity of these in vitro screening strategies should facilitate the selection and development of more effective nicotine conjugate vaccines. In addition, these data highlight a previously under-appreciated contribution of linkers and hapten-protein conjugations to conjugate vaccine immunogenicity by virtue of their inclusion in the epitope that binds and

  6. Human rotavirus vaccine Rotarix™ provides protection against diverse circulating rotavirus strains in African infants: a randomized controlled trial

    Directory of Open Access Journals (Sweden)

    Steele Andrew

    2012-09-01

    Full Text Available Abstract Background Rotaviruses are the most important cause of severe acute gastroenteritis worldwide in children Rotarix™ significantly reduced severe rotavirus gastroenteritis episodes in a Phase III clinical trial conducted in infants in South Africa and Malawi. This paper examines rotavirus vaccine efficacy in preventing severe rotavirus gastroenteritis, during infancy, caused by the various G and P rotavirus types encountered during the first rotavirus-season. Methods Healthy infants aged 5–10 weeks were enrolled and randomized into three groups to receive either two (10 and 14 weeks or three doses of Rotarix™ (together forming the pooled Rotarix™ group or three doses of placebo at a 6,10,14-week schedule. Weekly home visits were conducted to identify gastroenteritis episodes. Rotaviruses were detected by ELISA and genotyped by RT-PCR and nucleotide sequencing. The percentage of infants with severe rotavirus gastroenteritis caused by the circulating G and P types from 2 weeks post-last dose until one year of age and the corresponding vaccine efficacy was calculated with 95% CI. Results Overall, 4939 infants were vaccinated and 4417 (pooled Rotarix™ = 2974; placebo = 1443 were included in the per protocol efficacy cohort. G1 wild-type was detected in 23 (1.6% severe rotavirus gastroenteritis episodes from the placebo group. This was followed in order of detection by G12 (15 [1%] in placebo and G8 types (15 [1%] in placebo. Vaccine efficacy against G1 wild-type, G12 and G8 types were 64.1% (95% CI: 29.9%; 82%, 51.5% (95% CI:-6.5%; 77.9% and 64.4% (95% CI: 17.1%; 85.2%, respectively. Genotype P[8] was the predominant circulating P type and was detected in 38 (2.6% severe rotavirus gastroenteritis cases in placebo group. The remaining circulating P types comprised of P[4] (20 [1.4%] in placebo and P[6] (13 [0.9%] in placebo. Vaccine efficacy against P[8] was 59.1% (95% CI: 32.8%; 75.3%, P[4] was 70.9% (95% CI: 37.5%; 87

  7. Genomic and Phylogenetic Characterization of Novel, Recombinant H5N2 Avian Influenza Virus Strains Isolated from Vaccinated Chickens with Clinical Symptoms in China

    Directory of Open Access Journals (Sweden)

    Huaiying Xu

    2015-02-01

    Full Text Available Infection of poultry with diverse lineages of H5N2 avian influenza viruses has been documented for over three decades in different parts of the world, with limited outbreaks caused by this highly pathogenic avian influenza virus. In the present study, three avian H5N2 influenza viruses, A/chicken/Shijiazhuang/1209/2013, A/chicken/Chiping/0321/2014, and A/chicken/Laiwu/0313/2014, were isolated from chickens with clinical symptoms of avian influenza. Complete genomic and phylogenetic analyses demonstrated that all three isolates are novel recombinant viruses with hemagglutinin (HA and matrix (M genes derived from H5N1, and remaining genes derived from H9N2-like viruses. The HA cleavage motif in all three strains (PQIEGRRRKR/GL is characteristic of a highly pathogenic avian influenza virus strain. These results indicate the occurrence of H5N2 recombination and highlight the importance of continued surveillance of the H5N2 subtype virus and reformulation of vaccine strains.

  8. Bias in the Listeria monocytogenes enrichment procedure: Lineage 2 strains outcompete lineage 1 strains in University of Vermont selective enrichments

    DEFF Research Database (Denmark)

    Bruhn, Jesper Bartholin; Vogel, Birte Fonnesbech; Gram, Lone

    2005-01-01

    compounds in UVM I and II influenced this bias. The results of the present study demonstrate that the selective procedures used for isolation of L. monocytogenes may not allow a true representation of the types present in foods. Our results could have a significant impact on epidemiological studies...

  9. Sexual selection, sexual isolation and pheromones in Drosophila melanogaster strains after long-term maintaining on different diets.

    Science.gov (United States)

    Trajković, Jelena; Miličić, Dragana; Savić, Tatjana; Pavković-Lučić, Sofija

    2017-07-01

    Evolution of reproductive isolation may be a consequence of a variety of signals used in courtship and mate preferences. Pheromones play an important role in both sexual selection and sexual isolation. The abundance of pheromones in Drosophila melanogaster may depend on different environmental factors, including diet. The aim of this study was to ascertain to which degree principal pheromones affect sexual selection in D. melanogaster. We used D. melanogaster strains reared for 14 years on four substrates: standard cornmeal substrate and those containing tomato, banana and carrot. We have previously determined that long-term maintaining of these dietary strains resulted in differences in their cuticular hydrocarbons profile (CHs). In this work, we have tested the level of sexual selection and sexual isolation between aforementioned strains. We found that the high levels of cis-vaccenyl acetate, 7-pentacosene and 7,11-nonacosadiene in the strain reared on a substrate containing carrot affected the individual attractiveness and influenced sexual isolation between flies of this strain and flies reared on a substrate containing banana. Based on these results, long-term different diets, may contribute, to sexual behaviour of D. melanogaster via the effects of principal pheromones. Copyright © 2017 Elsevier B.V. All rights reserved.

  10. Combining selected immunomodulatory Propionibacterium freudenreichii and Lactobacillus delbrueckii strains: Reverse engineering development of an anti-inflammatory cheese.

    Science.gov (United States)

    Plé, Coline; Breton, Jérôme; Richoux, Romain; Nurdin, Marine; Deutsch, Stéphanie-Marie; Falentin, Hélène; Hervé, Christophe; Chuat, Victoria; Lemée, Riwanon; Maguin, Emmanuelle; Jan, Gwénaël; Van de Guchte, Maarten; Foligné, Benoit

    2016-04-01

    Inflammatory bowel disease (IBD) constitutes a growing public health concern in western countries. Bacteria with anti-inflammatory properties are lacking in the dysbiosis accompanying IBD. Selected strains of probiotic bacteria with anti-inflammatory properties accordingly alleviate symptoms and enhance treatment of ulcerative colitis in clinical trials. Such properties are also found in selected strains of dairy starters such as Propionibacterium freudenreichii and Lactobacillus delbrueckii (Ld). We thus investigated the possibility to develop a fermented dairy product, combining both starter and probiotic abilities of both lactic acid and propionic acid bacteria, designed to extend remissions in IBD patients. We developed a single-strain Ld-fermented milk and a two-strain P. freudenreichii and Ld-fermented experimental pressed cheese using strains previously selected for their anti-inflammatory properties. Consumption of these experimental fermented dairy products protected mice against trinitrobenzenesulfonic acid induced colitis, alleviating severity of symptoms, modulating local and systemic inflammation, as well as colonic oxidative stress and epithelial cell damages. As a control, the corresponding sterile dairy matrix failed to afford such protection. This work reveals the probiotic potential of this bacterial mixture, in the context of fermented dairy products. It opens new perspectives for the reverse engineering development of anti-inflammatory fermented foods designed for target populations with IBD, and has provided evidences leading to an ongoing pilot clinical study in ulcerative colitis patients. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  11. Safety and immunogenicity of inactivated poliovirus vaccine made from Sabin strains: a phase II, randomized, positive-controlled trial.

    Science.gov (United States)

    Liao, Guoyang; Li, Rongcheng; Li, Changgui; Sun, Mingbo; Li, Yanping; Chu, Jiayou; Jiang, Shude; Li, Qihan

    2012-01-15

    The production of Sabin inactivated poliovirus vaccine (IPV) can reduce biosafety requirements in the posteradication/post-oral poliovirus vaccine (OPV) era. We conducted a phase II, randomized, positive-controlled trial to assess the safety and immunogenicity of Sabin IPV. The test groups (A, B, and C) received 3 doses of high, middle, and low D antigen (D Ag) of Sabin IPV at ages 2, 3, and 4 months, respectively. Infants in 2 control groups, group D and group E, received 3 doses of trivalent OPV and conventional IPV (cIPV), respectively, on the same schedule as that of groups A, B, and C. Serum samples were collected before and 30 days after the administration of the third dose. In total, 500 infants were randomly assigned to 5 groups, and 449 infants completed the vaccine series. No serious adverse events were associated with vaccinations. After 3 doses, the seroconversion rates in groups A, B, C, D, and E were 100%, 97.8%, 96.6%, 100%, and 90.1%, respectively, for type 1 poliovirus; 97.7%, 95.7%, 78.7%, 100%, and 90.1%, respectively, for type 2; and 98.8%, 98.9%, 93.3%, 100%, and 97.8%, respectively, for type 3. Sabin IPV has good safety characteristics. The seroconversion rates for type 1 poliovirus (most appropriate concentration, 15 D Ag units [DU]), type 2 (32 DU), and type 3 (45 DU) Sabin IPV were similar to those of the OPV and cIPV control groups. NCT01056705.

  12. Affinity selection of Nipah and Hendra virus-related vaccine candidates from a complex random peptide library displayed on bacteriophage virus-like particles

    Energy Technology Data Exchange (ETDEWEB)

    Peabody, David S.; Chackerian, Bryce; Ashley, Carlee; Carnes, Eric; Negrete, Oscar

    2017-01-24

    The invention relates to virus-like particles of bacteriophage MS2 (MS2 VLPs) displaying peptide epitopes or peptide mimics of epitopes of Nipah Virus envelope glycoprotein that elicit an immune response against Nipah Virus upon vaccination of humans or animals. Affinity selection on Nipah Virus-neutralizing monoclonal antibodies using random sequence peptide libraries on MS2 VLPs selected peptides with sequence similarity to peptide sequences found within the envelope glycoprotein of Nipah itself, thus identifying the epitopes the antibodies recognize. The selected peptide sequences themselves are not necessarily identical in all respects to a sequence within Nipah Virus glycoprotein, and therefore may be referred to as epitope mimics VLPs displaying these epitope mimics can serve as vaccine. On the other hand, display of the corresponding wild-type sequence derived from Nipah Virus and corresponding to the epitope mapped by affinity selection, may also be used as a vaccine.

  13. Seasonal influenza vaccination coverage rate of target groups in selected cities and provinces in China by season (2009/10 to 2011/12.

    Directory of Open Access Journals (Sweden)

    Lei Zhou

    Full Text Available BACKGROUND: The objectives of the survey were to identify the level of influenza vaccination coverage in China in three influenza seasons 2009/10 to 2011/12, and to find out potential predictors for seasonal influenza vaccination. METHODS: In September and October 2011, representative urban household telephone surveys were conducted in five provinces in China with a response rate of 6%. Four target groups were defined for analysis: 1 children ≤ 5 years old; 2 elderly persons aged ≥ 60 years old; 3 health care workers (persons working in the medical field and 4 chronically ill persons. RESULTS: The overall mean vaccination rate was 9.0%. Among the four target groups, the rate of vaccination of children aged ≤ 5 years old (mean = 26% was highest and the rate of elderly people aged ≥ 60 years old (mean = 7.4% was the lowest, while the rates of persons who suffer from a chronic illness (mean = 9.4% and health care workers (9.5% were similar. A subsidy for influenza vaccination, age group, health care workers, suffering from a chronic illness and living in Eastern China were independent significant predictors for influenza vaccination. CONCLUSIONS: The seasonal influenza vaccination coverage rates among urban populations in selected cities and provinces in China were far below previously reported rates in developed countries. Influenza vaccination coverage rates differed widely between different target groups and provinces in China. Subsidy policy might have a positive effect on influenza vaccination rate, but further cost-effectiveness studies, as well as the vaccination rate associated factors studies are still needed to inform strategies to increase coverage.

  14. Decreasing Distortion Energies without Strain: Diazo-Selective 1,3-Dipolar Cycloadditions.

    Science.gov (United States)

    Gold, Brian; Aronoff, Matthew R; Raines, Ronald T

    2016-07-15

    The diazo group has attributes that complement those of the azido group for applications in chemical biology. Here, we use computational analyses to provide insights into the chemoselectivity of the diazo group in 1,3-dipolar cycloadditions. Dipole distortion energies are responsible for ∼80% of the overall energetic barrier for these reactions. Here, we show that diazo compounds, unlike azides, provide an opportunity to decrease that barrier substantially without introducing strain into the dipolarophile. The ensuing rate enhancement is due to the greater nucleophilic character of a diazo group compared to that of an azido group, which can accommodate decreased distortion energies without predistortion. The tuning of distortion energies with substituents in a diazo compound or dipolarophile can enhance reactivity and selectivity in a predictable manner. Notably, these advantages of diazo groups are amplified in water. Our findings provide a theoretical framework that can guide the design and application of both diazo compounds and azides in "orthogonal" contexts, especially for biological investigations.

  15. Resistance to Diamide Insecticides in Plutella xylostella (Lepidoptera: Plutellidae): Comparison Between Lab-Selected Strains and Field-Collected Populations.

    Science.gov (United States)

    Qin, Chao; Wang, Cheng-Hua; Wang, Ying-Ying; Sun, Shi-Qing; Wang, Huan-Huan; Xue, Chao-Bin

    2018-04-02

    Diamondback moth, Plutella xylostella (L.; Lepidoptera: Plutellidae), is an important pest of crucifers worldwide. The extensive use of diamide insecticides has led to P. xylostella resistance and this presents a serious threat to vegetable production. We selected chlorantraniliprole (Rf) and flubendiamide (Rh) resistance strains of P. xylostella with resistance ratios of 684.54-fold and 677.25-fold, respectively. The Rf and Rh strains underwent 46 and 36 generations of lab-selection for resistance, respectively. Low cross resistance of Rh to cyantraniliprole was found. Cross resistance to chlorfenapyr, tebufenozid, and indoxacarb was not found in Rf and Rh strains. The P. xylostella ryanodine receptor gene (PxRyR) transcripts level in the Rf and Rh strains was up-regulated. Except for Rf34 and Rh36, PxRyR expression in all generations of Rf and Rh selection gradually increased with increasing resistance. Two resistant populations were field-collected from Guangzhou Baiyun (Rb) and Zengcheng (Rz) and propagated for several generations without exposure to any pesticide had higher PxRyR expression than the susceptible strain (S). In the S strain, PxRyR expression was not related to the resistance ratio. Gene sequencing found that the RyR 4946 gene site was glycine (G) in the S, Rf, and Rh strains, and was glutamate (E) with 70% and 80% frequency in the Rb and Rz populations, respectively. The 4946 gene site was substituted by valine (V) with the frequency of 30% and 20% in Rb and Rz populations, respectively. These results increase the understanding of the mechanisms of diamide insecticide resistance in P. xylostella.

  16. Scientific consultation on the safety and containment of new poliovirus strains for vaccine production, clinical/regulatory testing and research. Report of a meeting held at NIBSC, Potters Bar, Hertfordshire, UK, 6/7th July 2016.

    Science.gov (United States)

    Minor, Philip D; Lane, Blanche; Mimms, South; Bar, Potters

    2017-07-01

    When poliomyelitis is totally eradicated from the natural world containment will be vital to prevent its re-emergence. The matter has become pressing as type 2 component of oral polio vaccine was completely withdrawn by May 2016 as wild ty[e 2 was declared eradicated. Work on polioviruses must be contained in accordance with GAPIII (the third version of the Global Action Plan of WHO). Some activities will be essential for years after eradication. Vaccine production and control, surveillance and supportive applied and academic research must all continue. Most laboratories do not currently comply with GAPIII and could not do so in the short term without disruption of essential activities including vaccine supply. The development and use of safer strains is raised in GAPIII and the meeting considered the strains available and the uses to which they could be put to facilitate compliance with the aims of GAPIII. Crown Copyright © 2017. Published by Elsevier Ltd. All rights reserved.

  17. The orotate transporter oroP from Lactococcus lactis can be used both as a very efficient, food-grade selection and counter-selection marker for strain construction in many different organisms

    DEFF Research Database (Denmark)

    Defoor, Els Marie Celine; Martinussen, Jan

    frame oroP on pDBORO necessary for the uptake of orotate was identified. A number of industrial important strains like Lactococcus lactis, Bacillus subtilus, and Bacillus licheniformis have been shown to be unable to metabolize orotate. If the oroP gene was introduced into these strains they acquired...... the ability to utilize orotate. If the strains had a pyrimidine requirement, the oroP gene could function as a selectable marker when growing in the presence of orotate as sole pyrimidine source. In an otherwise resistant strain, oroP was shown to sensitize the strain towards the analog 5-Fluoroorotate....... It was shown that strains who have lost the oroP gene could easily be selected in the presence of 5-Fluoroorotate, thus being an efficient counter-selection marker. pyrimidine-requiring strain (pyr B, C or D) orotate negative Counter-selection marker: wild-type strain! Fluoro-orotate resistant Functional...

  18. Molecular Characterization of Heterologous HIV-1gp120 Gene Expression Disruption in Mycobacterium bovis BCG Host Strain: A Critical Issue for Engineering Mycobacterial Based-Vaccine Vectors

    Science.gov (United States)

    Joseph, Joan; Fernández-Lloris, Raquel; Pezzat, Elías; Saubi, Narcís; Cardona, Pere-Joan; Mothe, Beatriz; Gatell, Josep Maria

    2010-01-01

    Mycobacterium bovis Bacillus Calmette-Guérin (BCG) as a live vector of recombinant bacterial vaccine is a promising system to be used. In this study, we evaluate the disrupted expression of heterologous HIV-1gp120 gene in BCG Pasteur host strain using replicative vectors pMV261 and pJH222. pJH222 carries a lysine complementing gene in BCG lysine auxotrophs. The HIV-1 gp120 gene expression was regulated by BCG hsp60 promoter (in plasmid pMV261) and Mycobacteria spp. α-antigen promoter (in plasmid pJH222). Among 14 rBCG:HIV-1gp120 (pMV261) colonies screened, 12 showed a partial deletion and two showed a complete deletion. However, deletion was not observed in all 10 rBCG:HIV-1gp120 (pJH222) colonies screened. In this study, we demonstrated that E. coli/Mycobacterial expression vectors bearing a weak promoter and lysine complementing gene in a recombinant lysine auxotroph of BCG could prevent genetic rearrangements and disruption of HIV 1gp120 gene expression, a key issue for engineering Mycobacterial based vaccine vectors. PMID:20617151

  19. Molecular Characterization of Heterologous HIV-1gp120 Gene Expression Disruption in Mycobacterium bovis BCG Host Strain: A Critical Issue for Engineering Mycobacterial Based-Vaccine Vectors

    Directory of Open Access Journals (Sweden)

    Joan Joseph

    2010-01-01

    Full Text Available Mycobacterium bovis Bacillus Calmette-Guérin (BCG as a live vector of recombinant bacterial vaccine is a promising system to be used. In this study, we evaluate the disrupted expression of heterologous HIV-1gp120 gene in BCG Pasteur host strain using replicative vectors pMV261 and pJH222. pJH222 carries a lysine complementing gene in BCG lysine auxotrophs. The HIV-1 gp120 gene expression was regulated by BCG hsp60 promoter (in plasmid pMV261 and Mycobacteria spp. α-antigen promoter (in plasmid pJH222. Among 14 rBCG:HIV-1gp120 (pMV261 colonies screened, 12 showed a partial deletion and two showed a complete deletion. However, deletion was not observed in all 10 rBCG:HIV-1gp120 (pJH222 colonies screened. In this study, we demonstrated that E. coli/Mycobacterial expression vectors bearing a weak promoter and lysine complementing gene in a recombinant lysine auxotroph of BCG could prevent genetic rearrangements and disruption of HIV 1gp120 gene expression, a key issue for engineering Mycobacterial based vaccine vectors.

  20. Bronquite infecciosa das galinhas: conhecimentos atuais, cepas e vacinas no Brasil Infectious bronchitis of chickens: current knowledge, strains and vaccines in Brazil

    Directory of Open Access Journals (Sweden)

    Juliana Figueiredo Pitangui Mendonça

    2009-11-01

    Full Text Available A bronquite infecciosa das galinhas (IB é uma doença viral aguda e altamente contagiosa que provoca grandes perdas econômicas à indústria avícola em todo o mundo. Considerando que surtos têm ocorrido no Brasil com emergência de novas variantes de IBV, desafiando as estratégias de vacinação atuais, este trabalho objetiva revisar os conhecimentos sobre IB e IBV, a sua distribuição, as cepas e as vacinas utilizadas no Brasil.Infectious bronchitis (IB is an acute, highly contagious disease of chickens, caused by infectious bronchitis virus (IBV, which results in great economic losses to the poultry industry worldwide, despite the routine use of vaccines. Several outbreaks do occur periodically in densely populated poultry regions in Brazil and there are constant emergence of new variants. The aim of this paper is to review the current knowledge about IBV and IB, the distribution, strains and vaccines in Brazil.

  1. Development of Th1 Imprints to rBCG Expressing a Foreign Protein: Implications for Vaccination against HIV-1 and Diverse Influenza Strains

    Directory of Open Access Journals (Sweden)

    Carl Power

    2010-01-01

    Full Text Available We demonstrate here that immunizing naïve mice with low numbers of recombinant Bacille Calmette-Guérin (rBCG expressing β-galactosidase (β-gal generates predominant Th1 responses to both BCG and β-gal whereas infection with high numbers generates a mixed Th1/Th2 response to both BCG and β-gal. Furthermore, the Th1 response to both BCG and β-gal is stable when mice, pre-exposed to low numbers of rBCG, are challenged four months later with high numbers of rBCG. Thus the Th1/Th2 phenotypes of the immune responses to β-gal and to BCG are “coherently” regulated. Such rBCG vectors, encoding antigens of pathogens preferentially susceptible to cell-mediated attack, may be useful in vaccinating against such pathogens. We discuss vaccination strategies employing rBCG vectors that are designed to provide protection against diverse influenza strains or numerous variants of HIV-1 and consider what further experiments are essential to explore the possibility of realizing such strategies.

  2. Generation and evaluation of a LaSota strain-based recombinant Newcastle disease virus (NDV) expressing the glycoprotein (G) of avian metapneumovirus subgroup C (aMPV-C) as a bivalent vaccine

    Science.gov (United States)

    To develop a bivalent vaccine, a recombinant Newcastle disease virus was generated by using the NDV LaSota strain with insertion of the G gene of aMPV-C. The biological assessments of the recombinant virus, rLS/aMPV-CG, by conducting the mean death time, intracerebral pathogenicity index, and growth...

  3. Specific selection for virulent urinary tract infectious Escherichia coli strains during catheter-associated biofilm formation

    DEFF Research Database (Denmark)

    Ferrieres, Lionel; Hancock, Viktoria; Klemm, Per

    2007-01-01

    microorganisms can attach. Urinary tract infectious (UTI) Escherichia coli range in pathogenicity and the damage they cause - from benign asymptomatic bacteriuria (ABU) strains, which inflict no or few problems to the host, to uropathogenic E. coli (UPEC) strains, which are virulent and often cause severe...... for and promote biofilm formation of the most virulent group of UTI E. coli strains, hardly a desirable situation for the catheterized patient....

  4. The effect of vaccination on the evolution and population dynamics of avian paramyxovirus-1.

    Directory of Open Access Journals (Sweden)

    Yee Ling Chong

    2010-04-01

    Full Text Available Newcastle Disease Virus (NDV is a pathogenic strain of avian paramyxovirus (aPMV-1 that is among the most serious of disease threats to the poultry industry worldwide. Viral diversity is high in aPMV-1; eight genotypes are recognized based on phylogenetic reconstruction of gene sequences. Modified live vaccines have been developed to decrease the economic losses caused by this virus. Vaccines derived from avirulent genotype II strains were developed in the 1950s and are in use globally, whereas Australian strains belonging to genotype I were developed as vaccines in the 1970s and are used mainly in Asia. In this study, we evaluated the consequences of attenuated live virus vaccination on the evolution of aPMV-1 genotypes. There was phylogenetic incongruence among trees based on individual genes and complete coding region of 54 full length aPMV-1 genomes, suggesting that recombinant sequences were present in the data set. Subsequently, five recombinant genomes were identified, four of which contained sequences from either genotype I or II. The population history of vaccine-related genotype II strains was distinct from other aPMV-1 genotypes; genotype II emerged in the late 19(th century and is evolving more slowly than other genotypes, which emerged in the 1960s. Despite vaccination efforts, genotype II viruses have experienced constant population growth to the present. In contrast, other contemporary genotypes showed population declines in the late 1990s. Additionally, genotype I and II viruses, which are circulating in the presence of homotypic vaccine pressure, have unique selection profiles compared to nonvaccine-related strains. Collectively, these data show that vaccination with live attenuated viruses has changed the evolution of aPMV-1 by maintaining a large effective population size of a vaccine-related genotype, allowing for coinfection and recombination of vaccine and wild type strains, and by applying unique selective pressures on

  5. Global Phenotypic Characterization of Effects of Fluoroquinolone Resistance Selection on the Metabolic Activities and Drug Susceptibilities of Clostridium perfringens Strains

    Directory of Open Access Journals (Sweden)

    Miseon Park

    2014-01-01

    Full Text Available Fluoroquinolone resistance affects toxin production of Clostridium perfringens strains differently. To investigate the effect of fluoroquinolone resistance selection on global changes in metabolic activities and drug susceptibilities, four C. perfringens strains and their norfloxacin-, ciprofloxacin-, and gatifloxacin-resistant mutants were compared in nearly 2000 assays, using phenotype microarray plates. Variations among mutant strains resulting from resistance selection were observed in all aspects of metabolism. Carbon utilization, pH range, osmotic tolerance, and chemical sensitivity of resistant strains were affected differently in the resistant mutants depending on both the bacterial genotype and the fluoroquinolone to which the bacterium was resistant. The susceptibilities to gentamicin and erythromycin of all resistant mutants except one increased, but some resistant strains were less susceptible to amoxicillin, cefoxitin, ceftriaxone, chloramphenicol, and metronidazole than their wild types. Sensitivity to ethidium bromide decreased in some resistant mutants and increased in others. Microarray analysis of two gatifloxacin-resistant mutants showed changes in metabolic activities that were correlated with altered expression of various genes. Both the chemical structures of fluoroquinolones and the genomic makeup of the wild types influenced the changes found in resistant mutants, which may explain some inconsistent reports of the effects of therapeutic use of fluoroquinolones on clinical isolates of bacteria.

  6. Evaluation of recombinant Mycoplasma hyopneumoniae P97/P102 paralogs formulated with selected adjuvants as vaccines against mycoplasmal pneumonia in pigs.

    Science.gov (United States)

    Woolley, Lauren K; Fell, Shayne A; Gonsalves, Jocelyn R; Raymond, Benjamin B A; Collins, Damian; Kuit, Tracey A; Walker, Mark J; Djordjevic, Steven P; Eamens, Graeme J; Jenkins, Cheryl

    2014-07-23

    Pig responses to recombinant subunit vaccines containing fragments of eight multifunctional adhesins of the Mycoplasma hyopneumoniae (Mhp) P97/P102 paralog family formulated with Alhydrogel(®) or Montanide™ Gel01 were compared with a commercial bacterin following experimental challenge. Pigs, vaccinated intramuscularly at 9, 12 and 15 weeks of age with either of the recombinant formulations (n=10 per group) or Suvaxyn(®) M. hyo (n=12), were challenged with Mhp strain Hillcrest at 17 weeks of age. Unvaccinated, challenged pigs (n=12) served as a control group. Coughing was assessed daily. Antigen-specific antibody responses were monitored by ELISA in serum and tracheobronchial lavage fluid (TBLF), while TBLF was also assayed for cytokine responses (ELISA) and bacterial load (qPCR). At slaughter, gross and histopathology of lungs were quantified and damage to epithelial cilia in the porcine trachea was evaluated by scanning electron microscopy. Suvaxyn(®) M. hyo administration induced significant serological responses against Mhp strain 232 whole cell lysates (wcl) and recombinant antigen F3P216, but not against the remaining vaccine subunit antigens. Alhydrogel(®) and Montanide™ Gel01-adjuvanted antigen induced significant antigen-specific IgG responses, with the latter adjuvant eliciting comparable Mhp strain 232 wcl specific IgG responses to Suvaxyn(®) M. hyo. No significant post-vaccination antigen-specific mucosal responses were detected with the recombinant vaccinates. Suvaxyn(®) M. hyo was superior in reducing clinical signs, lung lesion severity and bacterial load but the recombinant formulations offered comparable protection against cilial damage. Lower IL-1β, TNF-α and IL-6 responses after challenge were associated with reduced lung lesion severity in Suvaxyn(®) M. hyo vaccinates, while elevated pathology scores in recombinant vaccinates corresponded to cytokine levels that were similarly elevated as in unvaccinated pigs. This study highlights

  7. Characterization and efficacy determination of commercially available Central American H5N2 avian influenza vaccines for poultry.

    Science.gov (United States)

    Eggert, Dawn; Thomas, Colleen; Spackman, Erica; Pritchard, Nikki; Rojo, Francisco; Bublot, Michel; Swayne, David E

    2010-06-23

    A poultry vaccination program was implemented in Central America beginning in January 1995 to control both H5N2 low (LPAI) and high pathogenicity avian influenza. This study was conducted to identify seed strain composition and the efficacy of 10 commercially available H5 vaccines against challenge with H5N2 LPAI viruses isolated from Latin America in 2003. The original 1994 vaccine seed virus in commercial inactivated vaccines did not significantly reduce challenge virus shed titers. However, two seed strains of inactivated vaccines, genetically more closely related to the challenge virus, did significantly reduce titers of challenge virus shed from respiratory tract. In addition, a live recombinant fowlpox virus vaccine containing a more distantly related Eurasian lineage H5 gene insert significantly reduced respiratory shedding as compared to sham vaccinates. These results demonstrate the feasibility of identifying vaccine seed strains in commercial finished products for regulatory verification and the need for periodic challenge testing against current field strains in order to select efficacious vaccine seed strains. (c) 2010 Elsevier Ltd. All rights reserved.

  8. Selection of yeast strains for the production of alcohol from lactoserum

    Energy Technology Data Exchange (ETDEWEB)

    Laham-Guillaume, M; Moulin, G; Galzy, P

    1979-01-01

    Five of 11 yeast strains tested fermented 85 g lactose/L to approximately 5% EtOH. Four of these strains, Candida pseudotropicalis CBS 19384 and IP 513, and Kluyveromyces fragilis CBS 397, and CBS 5795, anaerobically fermented deproteinized whey to EtOH.

  9. Lethality and Developmental Delay of Drosophila melanogaster Following Ingestion of Selected Pseudomonas fluorescens Strains

    Science.gov (United States)

    Pseudomonas fluorescens secretes antimicrobial compounds that promote plant health and provide protection from pathogens. We used a non-invasive feeding assay to study the toxicity of P. fluorescens strains Pf0-1, SBW25, and Pf-5 to Drosophila melanogaster. The three strains of P. fluorescens varie...

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

    Science.gov (United States)

    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...

  11. Protective Vaccine Efficacy of the Complete Form of PPE39 Protein from Mycobacterium tuberculosis Beijing/K Strain in Mice.

    Science.gov (United States)

    Kim, Ahreum; Hur, Yun-Gyoung; Gu, Sunwha; Cho, Sang-Nae

    2017-11-01

    The aim of this study was to evaluate the protective efficacy of MTBK_24820, a complete form of PPE39 protein derived from a predominant Beijing/K strain of Mycobacterium tuberculosis in South Korea. Mice were immunized with MTKB_24820, M. bovis Bacilli Calmette-Guérin (BCG), or adjuvant prior to a high-dosed Beijing/K strain aerosol infection. After 4 and 9 weeks, bacterial loads were determined and histopathologic and immunologic features in the lungs and spleens of the M. tuberculosis -infected mice were analyzed. Putative immunogenic T-cell epitopes were examined using synthetic overlapping peptides. Successful immunization of MTBK_24820 in mice was confirmed by increased IgG responses ( P tuberculosis Beijing/K-strain is frequently isolated from TB patients. Copyright © 2017 American Society for Microbiology.

  12. Characterisation of lactic acid bacteria in spontaneously fermented camel milk and selection of strains for fermentation of camel milk

    DEFF Research Database (Denmark)

    Fugl, Angelina June Brandt; Berhe, Tesfemariam; Kiran, Anil

    2017-01-01

    The microbial communities in spontaneously fermented camel milk from Ethiopia were characterised through metagenomic 16S rRNA sequencing and lactic acid bacteria were isolated with the goal of selecting strains suitable as starter cultures. The fermented camel milk microbiota was dominated either...... by Lactobacillales or by Enterobacteriaceae, depending on incubation temperature and the provider of the milk. Strains of species with a potential use as starter cultures i.e., Lactococcus lactis, Lactobacillus plantarum, and Pediococcus acidilactici, were isolated. Fast acidifiers of camel milk have been isolated...

  13. Strain selection, biomass to biofuel conversion, and resource colocation have strong impacts on the economic performance of algae cultivation sites

    Energy Technology Data Exchange (ETDEWEB)

    Venteris, Erik R.; Wigmosta, Mark S.; Coleman, Andre M.; Skaggs, Richard

    2014-09-16

    Decisions involving strain selection, biomass to biofuel technology, and the location of cultivation facilities can strongly influence the economic viability of an algae-based biofuel enterprise. In this contribution we summarize our past results in a new analysis to explore the relative economic impact of these design choices. We present strain-specific growth model results from two saline strains (Nannocloropsis salina, Arthrospira sp.), a fresh to brackish strain (Chlorella sp., DOE strain 1412), and a freshwater strain of the order Sphaeropleales. Biomass to biofuel conversion is compared between lipid extraction (LE) and hydrothermal liquefaction (HTL) technologies. National-scale models of water, CO2 (as flue gas), land acquisition, site leveling, construction of connecting roads, and transport of HTL oil to existing refineries are used in conjunction with estimates of fuel value (from HTL) to prioritize and select from 88,692 unit farms (UF, 405 ha in pond area), a number sufficient to produce 136E+9 L yr-1 of renewable diesel (36 billion gallons yr-1, BGY). Strain selection and choice of conversion technology have large economic impacts, with differences between combinations of strains and biomass to biofuel technologies being up to $10 million dollars yr-1 UF-1. Results based on the most productive species, HTL-based fuel conversion, and resource costs show that the economic potential between geographic locations within the selection can differ by up to $4 million yr-1 UF-1, with 2.0 BGY of production possible from the most cost-effective sites. The local spatial variability in site rank is extreme, with very high and low rank sites within 10s of km of each other. Colocation with flue gas sources has a strong influence on site rank, but the most costly resource component varies from site to site. The highest rank sites are located predominantly in Florida and Texas, but most states south of 37°N latitude contain promising locations. Keywords: algae

  14. High strain amount in recessed junctions induced by selectively deposited boron-doped SiGe layers

    Energy Technology Data Exchange (ETDEWEB)

    Radamson, H.H. [School of Information and Communication Technology, KTH (Royal Institute of Technology) Isafjordsg. 22-26, Electrum 229, 16640 Kista (Sweden)], E-mail: rad@kth.se; Kolahdouz, M.; Ghandi, R.; Ostling, M. [School of Information and Communication Technology, KTH (Royal Institute of Technology) Isafjordsg. 22-26, Electrum 229, 16640 Kista (Sweden)

    2008-12-05

    This work presents the selective epitaxial growth (SEG) of Si{sub 1-x}Ge{sub x} (x = 0.15-0.315) layers with high amount of boron (1 x 10{sup 20}-1 x 10{sup 21} cm{sup -3}) in recessed or unprocessed (elevated) openings for source/drain applications in CMOS has been studied. The influence of the growth rate and strain on boron incorporation has been studied. A focus has been made on the strain distribution and boron incorporation in SEG of SiGe layers.

  15. High strain amount in recessed junctions induced by selectively deposited boron-doped SiGe layers

    International Nuclear Information System (INIS)

    Radamson, H.H.; Kolahdouz, M.; Ghandi, R.; Ostling, M.

    2008-01-01

    This work presents the selective epitaxial growth (SEG) of Si 1-x Ge x (x = 0.15-0.315) layers with high amount of boron (1 x 10 20 -1 x 10 21 cm -3 ) in recessed or unprocessed (elevated) openings for source/drain applications in CMOS has been studied. The influence of the growth rate and strain on boron incorporation has been studied. A focus has been made on the strain distribution and boron incorporation in SEG of SiGe layers

  16. Strain Selection, Biomass to Biofuel Conversion, and Resource Colocation have Strong Impacts on the Economic Performance of Algae Cultivation Sites

    Energy Technology Data Exchange (ETDEWEB)

    Venteris, Erik R., E-mail: erik.venteris@pnl.gov; Wigmosta, Mark S.; Coleman, Andre M.; Skaggs, Richard L. [Pacific Northwest National Laboratory, Richland, WA (United States)

    2014-09-16

    Decisions involving strain selection, biomass to biofuel technology, and the location of cultivation facilities can strongly influence the economic viability of an algae-based biofuel enterprise. We summarize our past results in a new analysis to explore the relative economic impact of these design choices. Our growth model is used to predict average biomass production for two saline strains (Nannochloropsis salina and Arthrospira sp.), one fresh to brackish strain (Chlorella sp., DOE strain 1412), and one freshwater strain (order Sphaeropleales). Biomass to biofuel conversion is compared between lipid extraction and hydrothermal liquefaction (HTL) technologies. National-scale models of water, CO{sub 2} (as flue gas), land acquisition, site leveling, construction of connecting roads, and transport of HTL oil to existing refineries are used in conjunction with estimates of fuel value (from HTL) to prioritize and select from 88,692 unit farms (UF, 405 ha in pond area), a number sufficient to produce 136E + 9 L year{sup −1} of renewable diesel [36 billion gallons year{sup −1} (BGY)]. Strain selection and choice of conversion technology have large economic impacts, with differences between combinations of strains and biomass to biofuel technologies being up to $10 million year{sup −1} UF{sup −1}. Results based on the most productive strain, HTL-based fuel conversion, and resource costs show that the economic potential between geographic locations within the selection can differ by up to 4 million year{sup −1} UF{sup −1}, with 1.8 BGY of production possible from the most cost-effective sites. The local spatial variability in site rank is extreme, with very high and low sites within 10 kms of each other. Colocation with flue gas sources has a strong influence on rank, but the most costly resource component varies from site to site. The highest rank UFs are located predominantly in Florida and Texas, but most states south of 37°N latitude contain promising

  17. Experimental induction of paromomycin resistance in antimony-resistant strains of L. donovani: outcome dependent on in vitro selection protocol.

    Directory of Open Access Journals (Sweden)

    Sarah Hendrickx

    Full Text Available Paromomycin (PMM has recently been introduced for treatment of visceral leishmaniasis in India. Although no clinical resistance has yet been reported, proactive vigilance should be warranted. The present in vitro study compared the outcome and stability of experimental PMM-resistance induction on promastigotes and intracellular amastigotes. Cloned antimony-resistant L. donovani field isolates from India and Nepal were exposed to stepwise increasing concentrations of PMM (up to 500 µM, either as promastigotes or intracellular amastigotes. One resulting resistant strain was cloned and checked for stability of resistance by drug-free in vitro passage as promastigotes for 20 weeks or a single in vivo passage in the golden hamster. Resistance selection in promastigotes took about 25 weeks to reach the maximal 97 µM inclusion level that did not affect normal growth. Comparison of the IC(50 values between the parent and the selected strains revealed a 9 to 11-fold resistance for the Indian and 3 to 5-fold for the Nepalese strains whereby the resistant phenotype was also maintained at the level of the amastigote. Applying PMM pressure to intracellular amastigotes produced resistance after just two selection cycles (IC(50 = 199 µM compared to the parent strain (IC(50 = 45 µM. In the amastigote-induced strains/clones, lower PMM susceptibilities were seen only in amastigotes and not at all in promastigotes. This resistance phenotype remained stable after serial in vitro passage as promastigote for 20 weeks and after a single in vivo passage in the hamster. This study clearly demonstrates that a different PMM-resistance phenotype is obtained whether drug selection is applied to promastigotes or intracellular amastigotes. These findings may have important relevance to resistance mechanism investigations and the likelihood of resistance development and detection in the field.

  18. Evaluation of a PCR multiplex for detection and differentiation of Mycoplasma synoviae, M. gallisepticum, and M. gallisepticum strain F-vaccine

    Directory of Open Access Journals (Sweden)

    Elena Mettifogo

    2015-01-01

    Full Text Available Mycoplasma gallisepticum (MG and Mycoplasma synoviae (MS are the mycoplasma infections of most concern for commercial poultry industry. MG infection is commonly designated as chronic respiratory disease (CRD of chickens and infections sinusitis of turkeys. MS causes sub clinical upper respiratory infection and tenosynovitis or bursitis in chickens and turkeys. The multiplex PCR was standardized to detect simultaneously the MS, MG field strains and MG F-vaccine strain specific. The generic PCR for detection of any species of Mollicutes Class was performed and compared to the multiplex PCR and to PCR using species-specific primers. A total of 129 avian tracheal swabs were collected from broiler-breeders, layer hens and broilers in seven different farms and were examined by multiplex PCR methods. The system (multiplex PCR demonstrated to be very rapid, sensitive, and specific. Therefore, the results showed a high prevalence of MS in the flocks examined (27.9%, and indicate that the MS is a recurrent pathogen in Brazilian commercial poultry flocks.

  19. In vitro sensitivity of Hungarian Actinobaculum suis strains to selected antimicrobials.

    Science.gov (United States)

    Biksi, I; Major, Andrea; Fodor, L; Szenci, O; Vetési, F

    2003-01-01

    In vitro antimicrobial sensitivity of 12 Hungarian isolates and the type strain ATCC 33144 of Actinobaculum suis to different antimicrobial compounds was determined both by the agar dilution and by the disc diffusion method. By agar dilution, MIC50 values in the range of 0.05-3.125 micrograms/ml were determined for penicillin, ampicillin, ceftiofur, doxycycline, tylosin, pleuromutilins, chloramphenicol, florfenicol, enrofloxacin and lincomycin. The MIC50 value of oxytetracycline and spectinomycin was 6.25 and 12.5 micrograms/ml, respectively. For ofloxacin, flumequine, neomycin, streptomycin, gentamicin, nalidixic acid, nitrofurantoin and sulphamethoxazole + trimethoprim MIC50 values were in the range of 25-100 micrograms/ml. With the disc diffusion method, all strains were sensitive to penicillin, cephalosporins examined, chloramphenicol and florfenicol, tetracyclines examined, pleuromutilins, lincomycin and tylosin. Variable sensitivity was observed for fluoroquinolones (flumequine, enrofloxacin, ofloxacin), most of the strains were susceptible to marbofloxacin. Almost all strains were resistant to aminoglycosides but most of them were sensitive to spectinomycin. A strong correlation was determined for disc diffusion and MIC results (Spearman's rho 0.789, p < 0001). MIC values of the type strain and MIC50 values of other tested strains did not differ significantly. Few strains showed a partially distinct resistance pattern for erythromycin, lincomycin and ampicillin in both methods.

  20. An Objective Approach for Burkholderia pseudomallei Strain Selection as Challenge Material for Medical Countermeasures Efficacy Testing

    OpenAIRE

    Van Zandt, Kristopher E.; Tuanyok, Apichai; Keim, Paul S.; Warren, Richard L.; Gelhaus, H. Carl

    2012-01-01

    Burkholderia pseudomallei is the causative agent of melioidosis, a rare disease of biodefense concern with high mortality and extreme difficulty in treatment. No human vaccines are available that protect against B. pseudomallei infection, and with the current limitations of antibiotic treatment, the development of new preventative and therapeutic interventions is crucial. Although clinical trials could be used to test the efficacy of new medical countermeasures (MCMs), the high mortality rate...

  1. Fermentation of Apple Juice with a Selected Yeast Strain Isolated from the Fermented Foods of Himalayan Regions and Its Organoleptic Properties

    OpenAIRE

    Kanwar, S. S.; Keshani,

    2016-01-01

    Twenty-three Saccharomyces cerevisiae strains isolated from different fermented foods of Western Himalayas have been studied for strain level and functional diversity in our department. Among these 23 strains, 10 S. cerevisiae strains on the basis of variation in their brewing traits were selected to study their organoleptic effect at gene level by targeting ATF1 gene, which is responsible for ester synthesis during fermentation. Significant variation was observed in ATF1 gene sequences, sugg...

  2. From tailor-made to ready-to-wear meningococcal B vaccines: longitudinal study of a clonal meningococcal B outbreak.

    Science.gov (United States)

    Caron, François; du Châtelet, Isabelle Parent; Leroy, Jean-Philippe; Ruckly, Corinne; Blanchard, Myriam; Bohic, Nicole; Massy, Nathalie; Morer, Isabelle; Floret, Daniel; Delbos, Valérie; Hong, Eva; Révillion, Martin; Berthelot, Gilles; Lemée, Ludovic; Deghmane, Ala-Eddine; Bénichou, Jacques; Lévy-Bruhl, Daniel; Taha, Muhamed-Kheir

    2011-06-01

    Outer-membrane-vesicle vaccines for meningococcal B outbreaks are complex and time consuming to develop. We studied the use of already available vaccine to control an outbreak caused by a genetically close strain. From 2006 to 2009, all individuals younger than 20 years living in the region of Normandy, France, in which an outbreak caused by a B:14:P1.7,16 strain occurred, were eligible to receive MenBvac, a Norwegian vaccine designed 20 years earlier against a strain sharing the same serosubtype (B:15:P1.7,16). The immunogenicity (in a randomly selected cohort of 400 children aged 1-5 years), safety, and epidemiological effect of the vaccination were assessed. 26,014 individuals were eligible to receive the vaccine. Shortage of vaccine production prompted start of the campaign in the highest incidence groups (1-5 years). 16,709 (64%) received a complete vaccination schedule of whom 13,589 (81%) received a 2+1 dose schedule (week 0, week 6, and month 8). At 6 weeks after the third dose, of 235 vaccinees for whom samples were available, 206 (88%) had a seroresponse, and 108 (56 %) of 193 had a seroresponse at 15 months. These results were similar to those described for tailor-made vaccines and their homologous strain. Only previously described adverse effects occurred. The incidence of B:14:P1.7,16 cases decreased significantly in the vaccine targeted population after the primary vaccination period (from 31·6 per 100,000 to 5·9 per 100,000; p=0·001). The ready-to-wear approach is reliable if epidemic and vaccine strains are genetically close. Other meningococcal B clonal outbreaks might benefit from this strategy; and previously described outer-membrane-vesicle vaccines can be effective against various strains. French Ministry of Health. Copyright © 2011 Elsevier Ltd. All rights reserved.

  3. A phase 1 study of a group B meningococcal native outer membrane vesicle vaccine made from a strain with deleted lpxL2 and synX and stable expression of opcA.

    Science.gov (United States)

    Keiser, Paul B; Gibbs, Barnett T; Coster, Trinka S; Moran, E Ellen; Stoddard, Mark B; Labrie, Joseph E; Schmiel, Deborah H; Pinto, Valerian; Chen, Ping; Zollinger, Wendell D

    2010-10-08

    This phase 1 clinical trial assessed the safety and immunogenicity of a native outer membrane vesicle (NOMV) vaccine prepared from a lpxL2(-) synX(-) mutant of strain 44/76 with opcA expression stabilized. Thirty-four volunteers were assigned to one of the three dose groups (25 mcg, 25 mcg with aluminum hydroxide adjuvant, and 50 mcg) to receive three intramuscular injections at 0, 6 and 24 weeks. Specific local and systemic adverse events (AEs) were solicited by diary and at visits on days 1, 2, 7 and 14 after each vaccination and at the end of the study at 30 weeks. Blood chemistries, complete blood count, and coagulation studies were measured on each vaccination day and again two days later. Blood for antibody measurements and bactericidal assays were drawn 0, 14, and 42 days after each vaccination. The proportion of volunteers who developed a fourfold or greater increase in serum bactericidal activity (SBA) to the wild-type parent of the vaccine strain with high opcA expression at 6 weeks after the third dose was 12/26 (0.46, 95% confidence interval 0.27-0.65). Antibody levels to OpcA were significantly higher in vaccine responders than in non-responders (p=0.008), and there was a trend for higher antibody levels to the lipooligosaccharide (LOS) (p=0.059). Bactericidal depletion assays on sera from volunteers with high-titer responses also indicate a major contribution of anti-OpcA and anti-LOS antibodies to the bactericidal response.These results suggest that genetically modified NOMV vaccines can induce protection against group B meningococcus. Copyright © 2010 Elsevier Ltd. All rights reserved.

  4. Construction and sequencing of an infectious clone of the goose embryo-adapted Muscovy duck parvovirus vaccine strain FZ91-30.

    Science.gov (United States)

    Wang, Jianye; Huang, Yu; Zhou, Mingxu; Hardwidge, Philip R; Zhu, Guoqiang

    2016-06-21

    Muscovy duck parvovirus (MDPV) is the etiological agent of Muscovy duckling parvoviral disease, which is characterized by diarrhea, locomotive dysfunction, stunting, and death in young ducklings, and causes substantial economic losses in the Muscovy duck industry worldwide. FZ91-30 is an attenuated vaccine strain that is safe and immunogenic to ducklings, but the genomic information and molecular mechanism underlining the attenuation are not understood. The FZ91-30 strain was propagated in 11-day-old embryonated goose eggs, and viral particles were purified from the pooled allantoic fluid by differential centrifugation and ultracentrifugation. Single-stranded genomic DNA was extracted and annealed to form double-stranded DNA. The dsDNA digested with NcoI resulted two sub-genomic fragments, which were then cloned into the modified plasmid pBluescript II SK, respectively, generating plasmid pBSKNL and pBSKNR. The sub-genomic plasmid clones were sequenced and further combined to construct the plasmid pFZ that contained the entire genome of strain FZ91-30. The complete genome sequences of strain FM and YY and partial genome sequences of other strains were retrieved from GenBank for sequence comparison. The plasmid pFZ containing the entire genome of FZ91-30 was transfected in 11-day-old embryonated goose eggs via the chorioallantoic membranes route to rescue infectious virus. A genetic marker was introduced into the rescued virus to discriminate from its parental virus. The genome of FZ91-30 consists of 5,131 nucleotides and has 98.9 % similarity to the FM strain. The inverted terminal repeats (ITR) are 456 nucleotides in length, 14 nucleotides longer than that of Goose parvovirus (GPV). The exterior 415 nucleotides of the ITR form a hairpin structure, and the interior 41 nucleotides constitute the D sequence, a reverse complement of the D' sequence at the 3' ITR. Amino acid sequence alignment of the VP1 proteins between FZ91-30 and five pathogenic MDPV strains

  5. Selection of aggressive pathogenic and solopathogenic strains of Ustilago maydis to improve Huitlacoche production

    Directory of Open Access Journals (Sweden)

    Porfirio Raúl Galicia-García

    Full Text Available ABSTRACT Ustilago maydis is a basidiomycete known as the causative agent of 'common smut', worldwide disease of maize that is recognized by the galls it forms, which have considerable potential as a gourmet food. Results of infection are quite variable, even under optimal greenhouse conditions. In order to find pathogenic strains able to be used as a highly infective and stable inoculum for the successful production of galls either in greenhouses or in the field, ears with gall symptoms containing teliospores were recovered from maize plants. The teliospores were suspended in water and plated on nutrient-rich medium. Twenty-six colonies developed, containing three types of yeast-like colonies: saprotrophic, pathogenic, and solopathogenic. DAPI staining confirmed the presence of solopathogenic strains with diploid sporidia. Groups of different mating types were found when pairs of the 26 strains were arranged resembling partial-diallel combinations. Amplification of the partial b locus revealed that the strains found harbor the alleles b3 and b4, allowing the formation in dikaryotic strains of heterodimeric regulatory proteins associated with fungal development and pathogenicity. In this study, we isolated compatible haploid and solopathogenic diploid strains for their high capacity for inducing smut.

  6. Genotypic and Phenotypic Assessment of Hyaluronidase among Type Strains of a Select Group of Staphylococcal Species

    Directory of Open Access Journals (Sweden)

    Mark E. Hart

    2009-01-01

    Full Text Available Hyaluronidases degrade hyaluronic acid, a major polysaccharide of the extracellular matrix of tissues, and are considered important for virulence in a number of Gram-positive and -negative bacteria. The purpose of the present study was to determine the prevalence of hyaluronidase among clinical strains of Staphylococcus aureus and among other Staphylococcus species. Spent media and chromosomal DNA were assessed for hyaluronidase activity and the absence or presence of a hyaluronidase gene (hysA by Southern analysis, respectively. All S. aureus strains examined exhibited at least one hybridizing band (half of the strains exhibited two or more hybridizing bands when probed for hysA and all but three of these strains produced hyaluronidase. In contrast, none of the type strains of 19 other species exhibited either hyaluronidase activity or hybridizing bands when probed for hysA. These data support the hypothesis that among members of the Staphylococcus genus only strains of S. aureus possess the enzyme hyaluronidase. This would suggest that hyaluronidase represents yet another potential virulence factor employed by S. aureus to cause disease and may represent a diagnostically important characteristic for distinguishing S. aureus from other members of this genus.

  7. Selection of non-Saccharomyces yeast strains for reducing alcohol levels in wine by sugar respiration.

    Science.gov (United States)

    Quirós, Manuel; Rojas, Virginia; Gonzalez, Ramon; Morales, Pilar

    2014-07-02

    Respiration of sugars by non-Saccharomyces yeasts has been recently proposed for lowering alcohol levels in wine. Development of industrial fermentation processes based on such an approach requires, amongst other steps, the identification of yeast strains which are able to grow and respire under the relatively harsh conditions found in grape must. This work describes the characterization of a collection of non-Saccharomyces yeast strains in order to identify candidate yeast strains for this specific application. It involved the estimation of respiratory quotient (RQ) values under aerated conditions, at low pH and high sugar concentrations, calculation of yields of ethanol and other relevant metabolites, and characterization of growth responses to the main stress factors found during the first stages of alcoholic fermentation. Physiological features of some strains of Metschnikowia pulcherrima or two species of Kluyveromyces, suggest they are suitable for lowering ethanol yields by respiration. The unsuitability of Saccharomyces cerevisiae strains for this purpose was not due to ethanol yields (under aerated conditions they are low enough for a significant reduction in final ethanol content), but to the high acetic acid yields under these growth conditions. According to results from controlled aeration fermentations with one strain of M. pulcherrima, design of an aeration regime allowing for lowering ethanol yields though preserving grape must components from excessive oxidation, would be conceivable. Copyright © 2014. Published by Elsevier B.V.

  8. Selective epitaxial growth properties and strain characterization of Si1- x Ge x in SiO2 trench arrays

    Science.gov (United States)

    Koo, Sangmo; Jang, Hyunchul; Ko, Dae-Hong

    2017-04-01

    In this study, we investigated the formation of a Si1- x Ge x fin structure in SiO2 trench arrays via an ultra-high-vacuum chemical-vapor deposition (UHV-CVD) selective epitaxial growth (SEG) process. Defect generation and microstructures of Si1- x Ge x fin structures with different Ge concentrations ( x = 0.2, 0.3 and 0.45) were examined. In addition, the strain evolution of a Si1- x Ge x fin structure was analyzed by using reciprocal space mapping (RSM). An (111) facet was formed from the Si1- x Ge x epi-layer and SiO2 trench wall interface to minimize the interface and the surface energy. The Si1- x Ge x fin structures were fully relaxed along the direction perpendicular to the trenches regardless of the Ge concentration. On the other hand, the fin structures were fully or partially strained along the direction parallel to the trenches depending on the Ge concentration: fully strained Si0.8Ge0.2 and Si0.7Ge0.3, and a Si0.55Ge0.45 strain-relaxed buffer. We further confirmed that the strain on the Si1- x Ge x fin structures remained stable after oxide removal and H2/N2 post-annealing.

  9. Isolation and Selection of Microalgal Strains from Natural Water Sources in Viet Nam with Potential for Edible Oil Production.

    Science.gov (United States)

    Thao, Tran Yen; Linh, Dinh Thi Nhat; Si, Vo Chi; Carter, Taylor W; Hill, Russell T

    2017-06-23

    fatty acids in these strains. Other strains had fatty acid compositions similar to that of palm oil. Several strains have been selected on the basis of their suitable fatty acid profiles and high lipid content for further chemical and physical characterization, toxicity and organoleptic tests of their oils, and for scale-up.

  10. Engineering Foot-and-Mouth Disease Viruses with Improved Growth Properties for Vaccine Development

    Science.gov (United States)

    Zheng, Haixue; Guo, Jianhong; Jin, Ye; Yang, Fan; He, Jijun; Lv, Lv; Zhang, Kesan; Wu, Qiong; Liu, Xiangtao; Cai, Xuepeng

    2013-01-01

    Background No licensed vaccine is currently available against serotype A foot-and-mouth disease (FMD) in China, despite the isolation of A/WH/CHA/09 in 2009, partly because this strain does not replicate well in baby hamster kidney (BHK) cells. Methodology/Principal Findings A novel plasmid-based reverse genetics system was used to construct a chimeric strain by replacing the P1 gene in the vaccine strain O/CHA/99 with that from the epidemic stain A/WH/CHA/09. The chimeric virus displayed growth kinetics similar to those of O/CHA/99 and was selected for use as a candidate vaccine strain after 12 passages in BHK cells. Cattle were vaccinated with the inactivated vaccine and humoral immune responses were induced in most of the animals on day 7. A challenge infection with A/WH/CHA/09 on day 28 indicated that the group given a 4-µg dose was fully protected and neither developed viremia nor seroconverted to a 3ABC antigen. Conclusions/Significance Our data demonstrate that the chimeric virus not only propagates well in BHK cells and has excellent antigenic matching against serotype A FMD, but is also a potential marker vaccine to distinguish infection from vaccination. These results suggest that reverse genetics technology is a useful tool for engineering vaccines for the prevention and control of FMD. PMID:23372840

  11. A multi-phase approach to select new wine yeast strains with enhanced fermentative fitness and glutathione production.

    Science.gov (United States)

    Bonciani, Tommaso; De Vero, Luciana; Mezzetti, Francesco; Fay, Justin C; Giudici, Paolo

    2018-03-01

    The genetic improvement of winemaking yeasts is a virtually infinite process, as the design of new strains must always cope with varied and ever-evolving production contexts. Good wine yeasts must feature both good primary traits, which are related to the overall fermentative fitness of the strain, and secondary traits, which provide accessory features augmenting its technological value. In this context, the superiority of "blind," genetic improvement techniques, as those based on the direct selection of the desired phenotype without prior knowledge of the genotype, was widely proven. Blind techniques such as adaptive evolution strategies were implemented for the enhancement of many traits of interest in the winemaking field. However, these strategies usually focus on single traits: this possibly leads to genetic tradeoff phenomena, where the selection of enhanced secondary traits might lead to sub-optimal primary fermentation traits. To circumvent this phenomenon, we applied a multi-step and strongly directed genetic improvement strategy aimed at combining a strong fermentative aptitude (primary trait) with an enhanced production of glutathione (secondary trait). We exploited the random genetic recombination associated to a library of 69 monosporic clones of strain UMCC 855 (Saccharomyces cerevisiae) to search for new candidates possessing both traits. This was achieved by consecutively applying three directional selective criteria: molybdate resistance (1), fermentative aptitude (2), and glutathione production (3). The strategy brought to the selection of strain 21T2-D58, which produces a high concentration of glutathione, comparable to that of other glutathione high-producers, still with a much greater fermentative aptitude.

  12. In vitro profiling of antimethicillin-resistant Staphylococcus aureus activity of thymoquinone against selected type and clinical strains.

    Science.gov (United States)

    Hariharan, P; Paul-Satyaseela, M; Gnanamani, A

    2016-03-01

    This study explores antimethicillin-resistant Staphylococcus aureus (MRSA) activity of a bioactive phytochemical constituent, thymoquinone obtained from the medicinal herb, Nigella sativa Linn. Based on initial assessment on crude extract of seeds of Nigella sativa Linn, the pure active constituent was employed in the study. A total of 99 MRSA strains which comprised of 40 types and 59 clinical strains were selected for the study. Minimum inhibitory concentration (MIC), bactericidal activity, postantibiotic effect (PAE) and propensity to select resistant mutants were determined using standard protocols. Results revealed that thymoquinone exhibited MIC in the range of 8-16 μg ml(-1) and MIC90 of 16 μg ml(-1) against MRSA strains. It was bactericidal to MRSA by demonstrating >3 log kill. It showed a longer PAE of 3·2 ± 0·2 h. Upon exposure to high-density inoculum of MRSA, it did not select resistant mutants. Transmission electron microscopy of thymoquinone-treated MRSA showed no lysis but damage to cell wall and cell membrane which corroborated well with the salt tolerance and bacteriolysis assays. In conclusion, MIC90 , bactericidal property, longer PAE, absence of resistant mutant selection and damages in cell membrane and cell wall imply a promising anti-MRSA activity of thymoquinone. This is the first detailed report on anti-MRSA activity of thymoquinone. The assessment was made with both type and clinical strains. Thymoquinone may be a potential lead compound which can be further optimized to discover novel anti-MRSA agents. © 2016 The Society for Applied Microbiology.

  13. Development of an indirect enzyme-linked immunosorbent assay (ELISA) to differentiate antibodies against wild-type porcine reproductive and respiratory syndrome from the vaccine strain TJM-F92 based on a recombinant Nsp2 protein.

    Science.gov (United States)

    Wang, X X; Wang, F X; Li, Z G; Wen, Y J; Wang, X; Song, N; Wu, H

    2018-01-01

    An accurate ELISA method to differentiate pigs infected with wild-type porcine reproductive and respiratory syndrome (PRRSV) strains from vaccinated ones would help to monitor PRRSV vaccination compliance. The recombinant protein GST-d120aa derived from the continuous deletion of 120 amino acids in the non-structural protein 2 region of the modified-live vaccine strain TJM-F92 was used to develop an indirect enzyme-linked immunosorbent assay (d120-ELISA) for differentiating serum antibodies against TJM-F92 from other PRRSV strains. At the optimized cut-off value which was calculated at an S/P of 0.25, it yielded a sensitivity of 90.7% and a specificity of 95.1%. Cross-reactivity tests suggested that the d120-ELISA was PRRSV-specific. Coefficient of variations of the repeatability tests ranged between 1.41-17.02%. The results suggest that the d120-ELISA is suitable for differentiating animals infected with wild-type strains from those immunized with MLV TJM-F92. Copyright © 2017. Published by Elsevier B.V.

  14. Suscetibilidade da linhagem de células Vero a cepas vacinais do vírus do sarampo Susceptibility of Vero cell line to vaccine strains of the measles virus

    Directory of Open Access Journals (Sweden)

    Célia Sayoko Takata

    1994-06-01

    Full Text Available A suscetibilidade da linhagem de células Vero ao vírus do sarampo é bem conhecida e sua utilização no controle da potência da vacina contra o sarampo é amplamente difundida. Com o objetivo de comparar a suscetibilidade de células Vero empregadas em titulações, amostras provenientes de dois laboratórios controladores (Vero IB e Vero INCQS, foram testadas frente a três cepas vacinais: Moraten, Schwarz e Biken CAM-70. Foram titulados 72 lotes de vacinas contra o sarampo, sendo 25 produzidos com a cepa Moraten, 24 com a cepa Schwarz e 23 com a cepa Biken CAM-70. A análise estatística dos resultados obtidos nas titulações, feita através dos testes Limites para uma Média e "t" de Student, mostrou que para as cepas Moraten e Biken CAM-70, as diferenças de títulos não foram estatisticamente significantes, o mesmo não ocorrendo com a cepa Schwarz, para a qual as células Vero IB se mostraram mais sensíveis.Vero cells used by distinct measles vaccine control laboratories had their susceptibility to Moraten, Schwarz and Biken CAM-70 vaccine strains assayed. Of a total of 72 lots of measles vaccine whose potency was titrated by microtechnique in two Vero cell samples (Vero IB and Vero INCQS, 25 had been produced with Moraten strain, 24 with Schwarz and 23 with Biken CAM-70. The statistical analysis of the results demonstrated that both Vero cells assayed presented comparable susceptibility to Moraten and Biken CAM-70 strains. As to the Schwarz strain, Vero IB cells were more susceptible than the other cell sample tested, thus confirming the existence of different sensitivities of Vero cells to some measles vaccine strains, or even to viruses derived from the same strain but with different passage histories. An altered cell susceptibility to virus replication may significantly alter the results in potency testing. Such alteration may be caused not only by the adoption of distinct protocols for the maintenance of cell cultures by

  15. The status of vaccine availability and associated factors in Tshwane government clinics.

    Science.gov (United States)

    Ngcobo, Ntombenhle Judith; Kamupira, Mercy G

    2017-05-24

    Vaccines have greatly contributed to the control of vaccine-preventable diseases and to human development. Efforts by many countries to introduce new vaccines are a significant move towards achieving the sustainable development goal for health. However, effective vaccine supply chains that ensure an uninterrupted supply of vaccines are pivotal to attaining universal access to life-saving vaccines and sustainable development. The introduction of new vaccines puts a strain on supply chains; South Africa (SA) is no exception, as there are indications of vaccine stock-outs in clinics. To establish the status of vaccine availability and associated factors in government health facilities of Tshwane Health District in Gauteng Province, SA. A cross-sectional study was conducted in a sample of randomly selected government clinics in the Tshwane health district of Gauteng Province. Data were collected using a structured measurement instrument in participating clinics. Data were analysed using Excel-based software (Microsoft, USA). A total of 31 clinics participated. In the preceding 12 months, clinics had experienced vaccine stock-outs, especially of the three newer vaccines: pneumococcal conjugate vaccine, rotavirus and Pentaxim. These were also out of stock for a long duration; for over 2 weeks in a majority of clinics. The causes of vaccine stock-outs were: poor management of stock, district depot out of stock, unreliable deliveries, lack of pharmacy assistants and limited fridge capacity. Further burdening the situation is the ineffective emergency-ordering system. Significant shortages of vaccines, which are essential drugs, occur in Tshwane government clinics. Vaccine supply chain issues and vaccine shortages should be treated as a priority at all levels of the healthcare system; therefore, a similar study should be conducted at national level. It is recommended that the vaccine supply chain should be restructured and overhauled with the use of advances in technology

  16. The status of vaccine availability and associated factors in Tshwane government clinics

    Directory of Open Access Journals (Sweden)

    Ntombenhle Judith Ngcobo

    2017-06-01

    Full Text Available Background. Vaccines have greatly contributed to the control of vaccine-preventable diseases and to human development. Efforts by many countries to introduce new vaccines are a significant move towards achieving the sustainable development goal for health. However, effective vaccine supply chains that ensure an uninterrupted supply of vaccines are pivotal to attaining universal access to life-saving vaccines and sustainable development. The introduction of new vaccines puts a strain on supply chains; South Africa (SA is no exception, as there are indications of vaccine stock-outs in clinics. Objective. To establish the status of vaccine availability and associated factors in government health facilities of Tshwane Health District in Gauteng Province, SA. Methods. A cross-sectional study was conducted in a sample of randomly selected government clinics in the Tshwane health district of Gauteng Province. Data were collected using a structured measurement instrument in participating clinics. Data were analysed using Excel-based software (Microsoft, USA. Results. A total of 31 clinics participated. In the preceding 12 months, clinics had experienced vaccine stock-outs, especially of the three newer vaccines: pneumococcal conjugate vaccine, rotavirus and Pentaxim. These were also out of stock for a long duration; for over 2 weeks in a majority of clinics. The causes of vaccine stock-outs were: poor management of stock, district depot out of stock, unreliable deliveries, lack of pharmacy assistants and limited fridge capacity. Further burdening the situation is the ineffective emergency-ordering system. Conclusion. Significant shortages of vaccines, which are essential drugs, occur in Tshwane government clinics. Vaccine supply chain issues and vaccine shortages should be treated as a priority at all levels of the healthcare system; therefore, a similar study should be conducted at national level. It is recommended that the vaccine supply chain should

  17. Vaccination: problems and perspectives.

    Directory of Open Access Journals (Sweden)

    S. M. Kharit

    2009-01-01

    Full Text Available Massive vaccination had proved its effective morbidity reduction. Today it is necessary to extend vaccination schedule, creation of selective, regional schedules based on epidemiological, clinical, economical substantiation. Development of vaccination needs the profound scientific research, modernization of adverse reaction observing system, betterment training system and awareness of population.

  18. Antibacterial activity of fumaria indica (hausskn.) pugsley against selected bacterial strains

    International Nuclear Information System (INIS)

    Toor, Y.; Nawaz, K.; Hussain, K.

    2015-01-01

    Antibacterial properties of methanolic extracts of F. indica prepared in different doses against seven Gram-positive and Gram-negative bacterial strains i.e. Streptococcus pyogenes, Staphylococcus aureus (1), Staphylococcus aureus (2), Shigella sonnei, Escherichia coli (1), Escherichia coli (2) and Neisseria gonorrhoeae using agar well diffusion method (inhibition zone measurements) compared to gentamicin as standard antibiotic. Results showed significant activities against the test organisms with overall satisfactory statistics. Streptococcus pyogenes, Staphylococcus aureus strains as well as Neisseria gonorrhoeae showed more inhibition to methanolic extracts of F. indica. Minimum inhibitory as well as minimum bactericidal concentrations against all strains except Shigella sonnei were also recorded. Studies showed promising horizons for the use of F. indica as an active antibacterial component in modern drug formulations. (author)

  19. Impact of interplay between magnetic field, transformation strain, and coarsening on variant selection in L10-type FePd

    International Nuclear Information System (INIS)

    Ueshima, N.; Yasuda, H.; Yoshiya, M.; Fukuda, T.; Kakeshita, T.

    2014-01-01

    Variant selection of L1 0 -type ferromagnetic alloys has been numerically investigated using the phase-field modeling, to clarify the phenomena at greater temporal and spatial resolution and to reveal the underlying mechanism. The duration for which the external magnetic field is effective is found to be very short, and variant selection is significantly affected by not only direct response to the external magnetic field but also their interplay between the field, intrinsic transformation strain, and various thermodynamic energy components involved in the course of microstructure evolution. The detailed mechanism of the interplay was quantitatively analyzed in terms of the driving force for the variant selection, by partitioning it into the various energy components. Careful examination of the variant selection at the very early stage revealed that the slight difference in size and configuration of variants during disorder-to-order transition realized by the interplay between transformation strain and external field is essentially needed before proceeding to the latter stage of the variant selection driven by interface energy