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Sample records for single vaccine strain

  1. 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.

  2. 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.

  3. 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...

  4. Safety and immunogenicity of single-dose live oral cholera vaccine strain CVD 103-HgR in healthy adults age 18-45.

    Science.gov (United States)

    McCarty, James M; Lock, Michael D; Hunt, Kristin M; Simon, Jakub K; Gurwith, Marc

    2018-02-01

    The attenuated recombinant Vibrio cholerae O1 vaccine strain CVD 103-HgR, re-developed as PXVX0200, elicits a rapid serum vibriocidal antibody (SVA) response and protects against cholera diarrhea in volunteer challenge studies. We performed a phase 3, placebo controlled, double blind, multi-center study to further assess the safety, immunogenicity, and lot-to-lot consistency of PXVX0200. Adult volunteers 18-45 years of age were randomized 8:1 to receive a single dose of 1 × 10 9 CFU of PXVX0200 from three production lots or saline placebo. Immunogenicity endpoints included SVA and anti-cholera toxin (CT) antibody levels on days 1, 11, 29, 91 and 181. Safety was assessed by comparing solicited signs and symptoms on days 1-8, unsolicited adverse events through day 29 and serious adverse events through day 181. A total of 3146 participants were enrolled, including 2795 vaccine and 351 placebo recipients. The SVA seroconversion rates at day 11 were 94% and 4% in the PXVX0200 and placebo recipients, respectively (P < .0001). Cumulative SVA seroconversion occurred among 96% of vaccine recipients. PXVX0200 SVA GMTs peaked on day 11 and remained significantly higher than placebo through day 181 while the fold-rise over baseline in PXVX0200 anti-CT antibody was significantly greater than placebo at every post-vaccination time point. Most reactogenicity was mild and resolved within 1-3 days with headache and diarrhea more frequently reported in PXVX0200 recipients. There were no differences in unsolicited adverse events and no study-related serious adverse events. Immunogenicity and safety endpoints were equivalent between the three production lots. PXVX0200 is immunogenic and well tolerated across multiple production lots. Clinicaltrials.gov NCT02094586. Copyright © 2018 The Authors. Published by Elsevier Ltd.. All rights reserved.

  5. 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...

  6. vaccination with newcastle disease vaccines strain i2 and lasota

    African Journals Online (AJOL)

    UP Employee

    SUMMARY. Vaccination trials and comparative immunogenicity study using Newcastle disease vaccine strain I2 (NDVI2) and NDV La Sota administered to commercial and local chickens through intraocular (i/o), intramuscular (i/m), drinking water (dw), untreated sorghum, parboiled sorghum, sorghum coated with gum ...

  7. Immunogenicity of single dose live attenuated hepatitis a vaccine.

    Science.gov (United States)

    Bhave, Sheila; Bavdekar, Ashish; Sapru, Amita; Bawangade, Seema; Pandit, Anand

    2011-02-01

    A long-term immunogenicity study of a single dose live attenuated H2 strain hepatitis A vaccine is being conducted in healthy Indian children at KEM Hospital, Pune. 131 of the original 143 children vaccinated in 2004, were evaluated for anti-HAV antibodies 30 months post vaccination (2007). Seroprotective antibody levels >20 mIU/mL were demonstrated in 87.8 % subjects with an overall GMT of 92.02 mIU/mL. No hepatitis like illness was recorded in any of the subjects since vaccination.

  8. Ability of vaccine strain induced antibodies to neutralize field isolates of caliciviruses from Swedish cats.

    Science.gov (United States)

    Wensman, Jonas Johansson; Samman, Ayman; Lindhe, Anna; Thibault, Jean-Christophe; Berndtsson, Louise Treiberg; Hosie, Margaret J

    2015-12-12

    Feline calicivirus (FCV) is a common cause of upper respiratory tract disease in cats worldwide. Its characteristically high mutation rate leads to escape from the humoral immune response induced by natural infection and/or vaccination and consequently vaccines are not always effective against field isolates. Thus, there is a need to continuously investigate the ability of FCV vaccine strain-induced antibodies to neutralize field isolates. Seventy-eight field isolates of FCV isolated during the years 2008-2012 from Swedish cats displaying clinical signs of upper respiratory tract disease were examined in this study. The field isolates were tested for cross-neutralization using a panel of eight anti-sera raised in four pairs of cats following infection with four vaccine strains (F9, 255, G1 and 431). The anti-sera raised against F9 and 255 neutralised 20.5 and 11.5 %, and 47.4 and 64.1 % of field isolates tested, respectively. The anti-sera against the more recently introduced vaccine strains G1 and 431 neutralized 33.3 and 55.1 % (strain G1) or 69.2 and 89.7 % (strain 431) of the field isolates with titres ≥5. [corrected]. Dual vaccine strains displayed a higher cross-neutralization. This study confirms previous observations that more recently introduced vaccine strains induce antibodies with a higher neutralizing capacity compared to vaccine strains that have been used extensively over a long period of time. This study also suggests that dual FCV vaccine strains might neutralize more field isolates compared to single vaccine strains. Vaccine strains should ideally be selected based on updated knowledge on the antigenic properties of field isolates in the local setting, and there is thus a need for continuously studying the evolution of FCV together with the neutralizing capacity of vaccine strain induced antibodies against field isolates at a national and/or regional level.

  9. Humoral response to calicivirus in captive tigers given a dual-strain vaccine.

    Science.gov (United States)

    Harrison, Tara M; Harrison, Scott H; Sikarskie, James G; Armstrong, Douglas

    2014-03-01

    The current feline vaccine with a single strain of calicivirus has been used for captive tigers, yet it may not protect against virulent systemic calicivirus infections. A cross-institutional study investigated the humoral response to a new dual-strain, killed-virus calicivirus vaccine for nine captive tigers. The subspecies of these tigers were Amur (Panthera tigris altaica), Bengal (Panthera tigris tigris), and Malayan (Panthera tigris jacksoni). Serum neutralization titers for virulent feline calicivirus strain FCV-DD1 were higher following dual-strain vaccine administration. There were no reports of adverse vaccine reactions. Dual-strain vaccination may afford broadened cross-protection against different calicivirus strains and is desirable to reduce the risk of virulent systemic calicivirus disease in tigers.

  10. Vaccine escape of piliated Streptococcus pneumoniae strains.

    Science.gov (United States)

    Regev-Yochay, Gili; Jaber, Hanaa; Hamdan, Ayob; Daana, Muhannad; Nammouz, Hanan; Thalji, Amin; Jaar, Fuad; Abdeen, Ziad; Rubin, Carmit; Huppert, Amit; Raz, Meir; Rahav, Galia

    2016-05-27

    Type1-pilus proteins were suggested as targets of future protein-based vaccines. Here we studied the effect of pneumococcal-conjugate vaccine (PCV7) implementation on the prevalence of piliated strains in a unique study setting which controls for typical confounders; the Palestinian-Israeli Collaborative Research (PICR). Annual cross-sectional surveys of pneumococcal carriage were performed during 2009-2011 among two closely related population that live under different health policies (a) Palestinian-Authority (PA) (n=1773), where PCV7 was not yet introduced (b) East-Jerusalem (EJ) (n=983) where PCV7 was rapidly implemented. Clinical data were collected, pneumococci identified and characterized and the presence of Type1-pilus genes was determined by rrgC PCR. Following PCV7 implementation in EJ, overall carriage prevalence did not change (∼30%), but VT7 strains decreased from 61.5% to 33.8%. While prevalence of non-piliated-VT7 isolates decreased from 37% to 10%, p<0.001, the prevalence of piliated-VT7 strains persisted ∼25%. Additionally, piliated non-VT13 strains emerged (1-15%, p<0.001). These changes were not observed in PA. These dynamics were independent of the bacteria's resistance pattern. A differential effect of PCV7 was observed with a relative resistance of piliated strains to the vaccine. This suggests that Type1-pilus confers an intrinsic advantage for colonization and may be an attractive vaccine target. Copyright © 2016 Elsevier Ltd. All rights reserved.

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

    Science.gov (United States)

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

    2015-04-01

    Thirty-one bison heifers were randomly assigned to receive saline or a single vaccination with 10(10) CFU of Brucella abortus strain RB51. Some vaccinated bison were randomly selected for booster vaccination with RB51 at 11 months after the initial vaccination. Mean antibody responses to RB51 were greater (P RB51-vaccinated bison at 8, 16, and 24 weeks after the initial vaccination and at 8 weeks after the booster vaccination. The vaccinated bison had greater (P Brucella organisms in all tissues, except in retropharyngeal and supramammary lymph nodes. Our study suggests that RB51 booster vaccination is an effective vaccination strategy for enhancing herd immunity against brucellosis in bison. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

  12. Detection of Novel Rotavirus Strain by Vaccine Postlicensure Surveillance

    OpenAIRE

    Weinberg, Geoffrey A.; Teel, Elizabeth N.; Mijatovic-Rustempasic, Slavica; Payne, Daniel C.; Roy, Sunando; Foytich, Kimberly; Parashar, Umesh D.; Gentsch, Jon R.; Bowen, Michael D.

    2013-01-01

    Surveillance for rotavirus-associated diarrhea after implementation of rotavirus vaccination can assess vaccine effectiveness and identify disease-associated genotypes. During active vaccine postlicensure surveillance in the United States, we found a novel rotavirus genotype, G14P[24], in a stool sample from a child who had diarrhea. Unusual rotavirus strains may become more prevalent after vaccine implementation.

  13. 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 ...

  14. Strain predominance following exposure of vaccinated and naive pregnant gilts to multiple strains of porcine reproductive and respiratory syndrome virus.

    Science.gov (United States)

    Lager, Kelly M; Mengeling, William L; Wesley, Ronald D

    2003-05-01

    Two studies were performed in order to test the relative ability of different strains of porcine reproductive and respiratory syndrome virus (PRRSV) to replicate and cross the placental barrier in pregnant gilts. Study 1 comprised 6 nonvaccinated gilts. Study 2 comprised 8 nonvaccinated gilts and 12 gilts that were vaccinated twice before conception. On, or about, gestation day 90 all gilts were simultaneously exposed to 20 field strains of PRRSV (all strains were distinguishable by restriction fragment length polymorphism (RFLP) patterns). Gilts of study 1 were euthanized on day 7 postpartum. Gilts of study 2 were euthanized on, or about, gestation day 111. All gilts, pigs, and fetuses were tested for the presence and type of strain of PRRSV. Of 128 samples shown to contain PRRSV, 118 contained a single strain, 4 contained 2 strains, and 2 contained a strain or strains for which the RFLP pattern was undecipherable. Only 8 of the 20 strains were isolated from nonvaccinated gilts and their litters. And only 2 of the 20 strains (notably 2 of the same strains isolated from nonvaccinated gilts and their litters), were isolated from vaccinated gilts and their litters. Moreover, 1 of the 2 strains accounted for most (31 of 37; 84%) of the isolates from the vaccinated group. Collectively these results indicate that strains differ in their ability to replicate in pregnant gilts and cross the placental barrier. And they suggest that maternal immunity, although sometimes insufficient to prevent transplacental infection, can exert additional selective pressure.

  15. Efficacy of Dart or Booster Vaccination with Strain RB51 in Protecting Bison against Experimental Brucella abortus Challenge

    OpenAIRE

    Olsen, S. C.; Johnson, C. S.

    2012-01-01

    This study characterized the efficacy of the Brucella abortus strain RB51 vaccine in bison when delivered by single intramuscular vaccination (hand RB51), by single pneumatic dart delivery (dart RB51), or as two vaccinations approximately 13 months apart (booster RB51) in comparison to control bison. All bison were challenged intraconjunctivally in midgestation with 107 CFU of B. abortus strain 2308 (S2308). Bison were necropsied and sampled within 72 h of abortion or delivery of a live calf....

  16. 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

  17. Antigenic differentiation of classical swine fever vaccinal strain PAV-250 from other strains, including field strains from Mexico.

    Science.gov (United States)

    Mendoza, Susana; Correa-Giron, Pablo; Aguilera, Edgar; Colmenares, Germán; Torres, Oscar; Cruz, Tonatiuh; Romero, Andres; Hernandez-Baumgarten, Eliseo; Ciprián, Abel

    2007-10-10

    Twenty-nine classical swine fever virus (CSFv) strains were grown in the PK15 or SK6 cell lines. Antigenic differentiation studies were performed using monoclonal antibodies (McAbs), produced at Lelystad (CDI-DLO), The Netherlands. The monoclonals which were classified numerically as monoclonals 2-13. Epitope map patterns that resulted from the reactivity with McAbs were found to be unrelated to the pathogenicity of the viruses studied. Antigenic determinants were recognized by McAbs 5 and 8, were not detected in some Mexican strains; however, sites for McAb 6 were absent in all strains. The PAV-250 vaccine strain was recognized by all MAbs, except by MAb 6. Furthermore, the Chinese C-S vaccine strain was found to be very similar to the GPE(-) vaccine. None of the studied Mexican vaccines or field strains was found to be similar to the PAV-250 vaccine strain.

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

    Science.gov (United States)

    Olsen, S C; Johnson, C

    2012-05-01

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

  19. A effective DNA vaccine against diverse genotype J infectious hematopoietic necrosis virus strains prevalent in China

    Science.gov (United States)

    Xu, Liming; Zhao, Jingzhuang; Liu, Miao; Kurath, Gael; Ren, Guangming; LaPatra, Scott E.; Yin, Jiasheng; Liu, Hongbai; Feng, Jian; Lu, Tongyan

    2017-01-01

    Infectious hematopoietic necrosis virus (IHNV) is the most important pathogen threatening the aquaculture of salmonid fish in China. In this study, a DNA vaccine, designated pIHNch-G, was constructed with the glycoprotein (G) gene of a Chinese IHNV isolate SD-12 (also called Sn1203) of genotype J. The minimal dose of vaccine required, the expression of the Mx-1 gene in the muscle (vaccine delivery site) and anterior kidney, and the titers of the neutralizing antibodies produced were used to evaluate the vaccine efficacy. To assess the potential utility of the vaccine in controlling IHNV throughout China, the cross protective efficacy of the vaccine was determined by challenging fish with a broad range of IHNV strains from different geographic locations in China. A single 100 ng dose of the vaccine conferred almost full protection to rainbow trout fry (3 g) against waterborne or intraperitoneal injection challenge with IHNV strain SD-12 as early as 4 days post-vaccination (d.p.v.), and significant protection was still observed at 180 d.p.v. Intragenogroup challenges showed that the DNA vaccine provided similar protection to the fish against all the Chinese IHNV isolates tested, suggesting that the vaccine can be widely used in China. Mx-1 gene expression was significantly upregulated in the muscle tissue (vaccine delivery site) and anterior kidney in the vaccinated rainbow trout at both 4 and 7 d.p.v. Similar levels of neutralizing antibodies were determined with each of the Chinese IHNV strains at 60 and 180 d.p.v. This DNA vaccine should play an important role in the control of IHN in China.

  20. 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.

  1. 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.

  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. 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.

  4. 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.

  5. Genomic comparison between attenuated Chinese equine infectious anemia virus vaccine strains and their parental virulent strains.

    Science.gov (United States)

    Wang, Xuefeng; Wang, Shuai; Lin, Yuezhi; Jiang, Chenggang; Ma, Jian; Zhao, Liping; Lv, Xiaoling; Wang, Fenglong; Shen, Rongxian; Kong, Xiangang; Zhou, Jianhua

    2011-02-01

    A lentiviral vaccine, live attenuated equine infectious anemia virus (EIAV) vaccine, was developed in the 1970s, and this has made tremendous contributions to the control of equine infectious anemia (EIA) in China. Four key virus strains were generated during the attenuation of the EIAV vaccine: the original Liao-Ning strain (EIAV(LN40)), a donkey-adapted virulent strain (EIAV(DV117)), a donkey-leukocyte-attenuated vaccine strain (EIAV(DLV121)), and a fetal donkey dermal cell (FDD)-adapted vaccine strain (EIAV(FDDV13)). In this study, we analyzed the proviral genomes of these four EIAV strains and found a series of consensus substitutions among these strains. These mutations provide useful information for understanding the genetic basis of EIAV attenuation. Our results suggest that multiple mutations in a variety of genes in our attenuated EIAV vaccines not only provide a basis for virulence attenuation and induction of protective immunity but also greatly reduce the risk of reversion to virulence.

  6. Selection and characterization of vaccine strain for Enterovirus 71 vaccine development.

    Science.gov (United States)

    Chang, Jui-Yuan; Chang, Cheng-Peng; Tsai, Hutchinson Hau-Pong; Lee, Chen-Dou; Lian, Wei-Cheng; Ih-Jen-Su; Sai, I-Hsi; Liu, Chia-Chyi; Chou, Ai-Hsiang; Lu, Ya-Jung; Chen, Ching-Yao; Lee, Pi-Hsiu; Chiang, Jen-Ron; Chong, Pele Choi-Sing

    2012-01-17

    Enterovirus 71 (EV71) has recently emerged as an important neurotropic virus in Asia because effective medications and prophylactic vaccine against EV71 infection are not available. Based on the success of inactivated poliovirus vaccine, the Vero cell-based chemically inactivated EV71 vaccine candidate could be developed. Identification of EV71 vaccine strain which can grow to high titer in Vero cell and induce cross-genotype virus neutralizing antibody responses represents the first step in vaccine development. In this report we describe the characterization and validation of a clinical isolate E59 belonging to B4 sub-genotype based on VP1 genetic analysis. Before selected as the vaccine strain, the genetic stability of E59 in passage had been analyzed based on the nucleotide sequences obtained from the Master Virus Seed, Working Seed banks and the virus harvested from the production lots, and found to be identical to those found in the original isolate. These results indicate that E59 vaccine strain has strong genetic stability in passage. Using this vaccine strain the prototype EV71 vaccine candidate was produced from 20L of Vero cell grown in serum-containing medium. The production processes were investigated, characterized and quantified to establish the potential vaccine manufacturing process including the time for virus harvest, the membrane for diafiltration and concentration, the gel-filtration chromatography for the down-stream virus purification, and the methods for viral inactivation. Finally, the inactivated virion vaccine candidate containing sub-microgram of viral proteins formulated with alum adjuvant was found to induce strong virus neutralizing antibody responses in mice and rabbits. Therefore, these results provide valuable information for cell-based EV71 vaccine development. Copyright © 2011 Elsevier Ltd. All rights reserved.

  7. Variation of Housekeeping Genes in Clinical Isolates and Vaccine Strains of Bordetella pertussis.

    Science.gov (United States)

    Fathi, Masoumeh; Haghighi, Faezeh; Shahcheraghi, Fereshteh; Abbasi, Ebrahim; Eshraghi, Seyed Saeed; Ghourchian, Sedighe; Zeraati, Hojjat; Yaseri, Mehdi; Douraghi, Masoumeh; Shokri, Fazel

    2017-04-01

    Bordetella pertussis causes serious contagious infections, primarily in childhood. A whole-cell vaccine, diphtheria-tetanus-whole cell pertussis (DTwP), has been used to protect against pertussis in children in Iran, but the pertussis cases have been increasing during recent years. We determined the allelic variation level of housekeeping genes in isolates recovered from pertussis patients and vaccine strains used in national vaccination program. Five clinical isolates, 2 vaccine strains and a Tohama I strain were studied through multilocus sequence typing (MLST) of housekeeping genes. The relatedness between STs, the founder, single- and double-locus variants (SLVs, DLVs) was determined using eBURST algorithm. The concordance between the type assignments by MLST and PFGE was determined. In the 5 clinical isolates, 2 STs were identified, ST2 and ST79. The vaccine strains displayed two distinct allelic profiles assigned to ST1 and ST2. ST2 was predicted as founder and the remaining STs were SLVs of ST2. MLST and PFGE type assignments were 86.6% concordant. The clinical isolates of B. pertussis were different from vaccine strains used in the national vaccination program. This study confirms the low level of variation in housekeeping genes of B. pertussis. MLST of virulent antigenic genes needs to be applied as a complementary method for the characterization of new ST-harboring isolates that may predominate periodically. The combination of these data allows rapid and efficient surveillance of currently circulating isolates. These data might elucidate the future trends and considerations for vaccine formulation and design.

  8. Persistence of Immunity Acquired after a Single Dose of Rubella Vaccine in Japan.

    Science.gov (United States)

    Okafuji, Takao; Okafuji, Teruo; Nakayama, Tetsuo

    2016-05-20

    To date, Takahashi, Matsuura, and TO-336 strains of live-attenuated rubella vaccine have been used in Japan. Japan implemented a single-dose rubella vaccination program until 2006. However, few reports are available on the persistence of immunity after this vaccination program. We collected 276 serum samples from January 2009 to December 2011 at Okafuji Pediatric Clinic and assessed the immune status of these samples against rubella virus during 1-10 years after vaccination with a single dose of Takahashi rubella vaccine. Regional outbreak of rubella did not occur during 1999-2011. The collected serum samples were tested for antibodies against the rubella virus by performing a standard hemagglutination inhibition (HAI) test. Our results showed that all the tested serum samples contained antibodies against the rubella virus 10 years after the vaccination. Geometric mean titer of HAI antibodies was 1:180 and decreased to 1:68 at 10 years after the vaccination. The levels of HAI antibodies decreased logarithmically with time after the vaccination. In conclusion, vaccine-acquired immunity after vaccination with a single dose of live-attenuated Takahashi rubella vaccine was retained for at least 10 years when rubella was under regional control.

  9. 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.

  10. Brucella abortus strain RB51 vaccination in elk. I. Efficacy of reduced dosage.

    Science.gov (United States)

    Cook, Walter E; Williams, Elizabeth S; Thorne, E Tom; Kreeger, Terry J; Stout, Glen; Bardsley, Katie; Edwards, Hank; Schurig, Gerhardt; Colby, Lesley A; Enright, Fred; Elzer, Philip H

    2002-01-01

    Bovine brucellosis is a serious zoonotic disease affecting some populations of Rocky Mountain elk (Cervus elaphus nelsoni) and bison (Bison bison) in the Greater Yellowstone Area, USA. The fear that elk and/or bison may spread Brucella abortus to livestock has prompted efforts to reduce or eliminate the disease in wildlife. Brucella abortus strain RB51 (RB51) vaccine has recently been approved for use in cattle. Unlike strain 19 vaccine, RB51 does not cause false positive reactions on standard brucellosis serologic tests. If effective, it may become the vaccine of choice for wildlife. In February 1995, 45 serologically negative female elk calves were trapped and taken to the Sybille Wildlife Research and Conservation Education Unit near Wheatland, Wyoming, USA. In May 1995, 16 of these elk calves were hand-vaccinated with 1 x 10(9) colony forming units (CFU) of RB51, 16 were vaccinated with 1 x 10(8) CFU RB51 by biobullet, and 13 were given a saline placebo. The elk were bred in fall of 1996 and they were challenged with 1 x 10(7) CFU of B. abortus strain 2308 by intraconjunctival inoculation in March 1997. Thirteen (100%) control elk aborted, 14 (88%) hand-vaccinated elk aborted, and 12 (75%) biobullet vaccinated elk aborted or produced nonviable calves. These results suggest that a single dose of 1 x 10(8) to 1 x 10(9) CFU RB51 does not provide significant protection against B. abortus induced abortion in elk. However, the vaccine appears to be safe at this dose and additional study may reveal a more effective RB51 vaccine regimen for elk.

  11. Immunogenicity and efficacy of Hoshino strain of Mumps Vaccine in ...

    African Journals Online (AJOL)

    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 ...

  12. Efficacy of Brucella abortus vaccine strain RB51 compared to the reference vaccine Brucella abortus strain 19 in water buffalo

    Directory of Open Access Journals (Sweden)

    Vincenzo Caporale

    2010-03-01

    Full Text Available Approximately 250 000 water buffalo (Bubalus bubalis live in the Campania region of southern Italy where the breeding of this species is very popular. Of these animals, almost 150 000 are concentrated in the Caserta province where the prevalence of Brucella abortus in this species represents approximately 20% at herd level. The Italian brucellosis eradication programme provides a slaughter and vaccination strategy for this province. B. abortus strain RB51 (RB51 has become the official vaccine for the prevention of brucellosis in cattle in several countries. The aim of this study was to evaluate the efficacy of RB51 in water buffalo compared to the B. abortus S19 vaccine (S19. The study was performed in accordance with a protocol described in mice. Female buffalo aged five months were inoculated. Five received a RB51 dosage on two occasions that was three times greater than that approved for use in cattle and a booster after one month, five received B. abortus S19 vaccine at the standard dosage and three controls received a phosphate buffer solution. Buffalo were then challenged with a virulent B. abortus strain 544 thirty days post vaccination. Antibodies that developed in the five animals vaccinated with RB51 were not detected by the Rose Bengal test or complement fixation test (CFT and were also tested by CFT prepared with RB51 antigen. After culling, B. abortus was cultured from the spleen, retropharyngeal and supra-mammary lymph nodes. A statistical evaluation was performed to assess the immunogenicity values obtained in buffalo vaccinated with S19, compared to those obtained in buffalo vaccinated with the RB51 vaccine and in the unvaccinated control group.

  13. Efficacy of Brucella abortus vaccine strain RB51 compared to the reference vaccine Brucella abortus strain 19 in water buffalo.

    Science.gov (United States)

    Caporale, Vincenzo; Bonfini, Barbara; Di Giannatale, Elisabetta; Di Provvido, Andrea; Forcella, Simona; Giovannini, Armando; Tittarelli, Manuela; Scacchia, Massimo

    2010-01-01

    Approximately 250,000 water buffalo (Bubalus bubalis) live in the Campania region of southern Italy where the breeding of this species is very popular. Of these animals, almost 150,000 are concentrated in the Caserta province where the prevalence of Brucella abortus in this species represents approximately 20% at herd level. The Italian brucellosis eradication programme provides a slaughter and vaccination strategy for this province. B. abortus strain RB51 (RB51) has become the official vaccine for the prevention of brucellosis in cattle in several countries. The aim of this study was to evaluate the efficacy of RB51 in water buffalo compared to the B. abortus S19 vaccine (S19). The study was performed in accordance with a protocol described in mice. Female buffalo aged five months were inoculated. Five received a RB51 dosage on two occasions that was three times greater than that approved for use in cattle and a booster after one month, five received B. abortus S19 vaccine at the standard dosage and three controls received a phosphate buffer solution. Buffalo were then challenged with a virulent B. abortus strain 544 thirty days post vaccination. Antibodies that developed in the five animals vaccinated with RB51 were not detected by the Rose Bengal test or complement fixation test (CFT) and were also tested by CFT prepared with RB51 antigen. After culling, B. abortus was cultured from the spleen, retropharyngeal and supra-mammary lymph nodes. A statistical evaluation was performed to assess the immunogenicity values obtained in buffalo vaccinated with S19, compared to those obtained in buffalo vaccinated with the RB51 vaccine and in the unvaccinated control group.

  14. 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

  15. A Francisella tularensis Live Vaccine Strain That Improves Stimulation of Antigen-Presenting Cells Does Not Enhance Vaccine Efficacy

    OpenAIRE

    Schmitt, Deanna M.; O'Dee, Dawn M.; Horzempa, Joseph; Carlson, Paul E.; Russo, Brian C.; Bales, Jacqueline M.; Brown, Matthew J.; Nau, Gerard J.

    2012-01-01

    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 s...

  16. Efficacy of vaccination with La Sota strain vaccine to control Newcastle disease in village chickens in Nepal.

    Science.gov (United States)

    Shrestha, Sulochana; Dhawan, Mamta; Donadeu, Meritxell; Dungu, Baptiste

    2017-02-01

    The efficacy of vaccination with Newcastle disease (ND) La Sota and R 2 B (Mukteswar) modified live strain vaccines was determined by experimental challenge and with ND La Sota vaccine under field conditions in Nepal. Booster vaccination with ND La Sota vaccine after a primary vaccination with ND La Sota vaccine, induced a geometric mean titre (GMT) of 5.0 log 2 haemagglutination inhibition (HI) units, compared to a GMT of 6.0 log 2 HI units following booster vaccination with R 2 B vaccine 1 month after primary vaccination with ND La Sota vaccine. Both vaccines provided 100% protection against challenge with a local field ND strain. Furthermore, booster vaccination with ND La Sota vaccine induced protective levels of antibody after field use in villages in Jhapa, and no outbreaks of ND occurred during the study period. The ND La Sota modified live vaccine is immunogenic and efficacious and is a suitable vaccine for use in vaccination programmes in village chickens in the rural areas of Nepal.

  17. Safety of Brucella abortus strain RB51 vaccine in non-target ungulates and coyotes.

    Science.gov (United States)

    Kreeger, Terry J; DeLiberto, Thomas J; Olsen, Steven C; Edwards, William H; Cook, Walter E

    2002-07-01

    Brucellosis is endemic in free-ranging elk (Cervus elaphus) and bison (Bison bison) in the Greater Yellowstone Area (GYA; USA). It is possible that an oral brucellosis vaccine could be developed and disseminated in the GYA to reduce disease transmission. Should this occur, non-target species other than elk and bison may come in contact with the vaccine resulting in morbidity or mortality. To assess biosafety, bighorn sheep (Ovis canadensis; n = 10), pronghorn (Antilocapra americana; n = 9), mule deer (Odocoileus hemionus; n = 11), moose (Alces alces shirasi; n = 10), and coyotes (Canis latrans; n = 24) were given a single oral dose of at least 1.0 x 10(10) colony-forming units of Brucella abortus strain RB51 vaccine (RB51). Animals were randomly divided into vaccinated and control groups. Ungulates were captured, blood sampled, and swabs taken from the nares, rectum, and vagina for bacterial culture on day 0, 42, and 84 post-inoculation (PI). On day 42, the vaccinated group became a control group and vice versa in a crossover design. Blood and swab samples were taken from coyotes on days 0, 14, 28, and 42 PI. There was no crossover for the coyote study. Two coyotes from each group were also euthanized and cultured for RB51 on days 42, 84, 168, and 336 PI. Blood samples were analyzed for hematologic changes and antibodies to RB51 using a modified dot-blot assay. No morbidity or mortality as a result of vaccination was observed in any animal. There were no differences in hematologic parameters at any time for ungulate species; vaccinated coyotes had higher hematocrit, hemoglobin, and eosinophil counts (P RB51. Strain RB51 was cultured from oropharyngeal lymph nodes from one coyote 42 days PI and from a moose 117 days PI. This study suggested that a single oral dose of RB51 was safe in these species.

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

    Science.gov (United States)

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

    2015-01-01

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

  19. 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.

  20. 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

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

    Directory of Open Access Journals (Sweden)

    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

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

    Science.gov (United States)

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

    2013-10-01

    In Europe, the main reservoir and vector of rabies has been the red fox (Vulpes vulpes). Oral immunization of foxes with live vaccines, using attenuated rabies strains (SAD B19, SAD Bern), apathogenic mutants of an attenuated strain (SAG2) and the vaccinia-rabies glycoprotein recombinant virus vaccine (V-RG), has been shown to be the most effective method for the control and elimination of rabies. Among all vaccines currently used for wildlife oral vaccination, one vaccine (marketed as SAD Bern strain) has been widely used in Europe since 1992 with the distribution of 17million of baits in 2011. Because of the potential environmental safety risk of a live virus which could revert to virulence, the full genome sequencing of this vaccine was undertaken and the sequence was characterized and compared with those of referenced rabies viruses. The vaccine showed higher similarity to the strains belonging to the SAD B19 vaccine virus strains than to the SAD Bern vaccines. This study is the first one reporting on virus strain identity changes in this attenuated vaccine. Copyright © 2013 Elsevier B.V. All rights reserved.

  3. 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.

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

    Science.gov (United States)

    Olsen, S C; Johnson, C S

    2012-06-01

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

  5. 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

  6. Use of antigenic cartography in vaccine seed strain selection.

    Science.gov (United States)

    Fouchier, Ron A M; Smith, Derek J

    2010-03-01

    Human influenza A viruses are classic examples of antigenically variable pathogens that have a seemingly endless capacity to evade the host's immune response. The viral hemagglutinin (HA) and neuraminidase (NA) proteins are the main targets of our antibody response to combat infections. HA and NA continuously change to escape from humoral immunity, a process known as antigenic drift. As a result of antigenic drift, the human influenza vaccine is updated frequently. The World Health Organization (WHO) coordinates a global influenza surveillance network that, by the hemagglutination inhibition (HI) assay, routinely characterizes the antigenic properties of circulating strains in order to select new seed viruses for such vaccine updates. To facilitate a quantitative interpretation and easy visualization of HI data, a new computational technique called "antigenic cartography" was developed. Since its development, antigenic cartography has been applied routinely to assist the WHO with influenza surveillance activities. Until recently, antigenic variation was not considered a serious issue with influenza vaccines for poultry. However, because of the diversification of the Asian H5N1 lineage since 1996 into multiple genetic clades and subclades, and because of the long-term use of poultry vaccines against H5 in some parts of the world, this issue needs to be re-addressed. The antigenic properties of panels of avian H5N1 viruses were characterized by HI assay, using mammalian or avian antisera, and analyzed using antigenic cartography methods. These analyses revealed antigenic differences between circulating H5N1 viruses and the H5 viruses used in poultry vaccines. Considerable antigenic variation was also observed within and between H5N1 clades. These observations have important implications for the efficacy and long-term use of poultry vaccines.

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

    Directory of Open Access Journals (Sweden)

    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.

  8. Live Attenuated Tetravalent Dengue Virus Host Range Vaccine Is Immunogenic in African Green Monkeys following a Single Vaccination

    Science.gov (United States)

    Smith, Katherine M.; Piper, Amanda; Huitt, Emerson; Spears, Carla J.; Quiles, Michelle; Ribeiro, Mariana; Thomas, Malcolm E.; Brown, Dennis T.; Hernandez, Raquel

    2014-01-01

    ABSTRACT The causative agent of dengue fever, dengue virus (DENV), is transmitted by mosquitoes, and as distribution of these insects has expanded, so has dengue-related disease. DENV is a member of the Flaviviridae family and has 4 distinct serotypes (DENV-1, -2, -3, and -4). No lasting cross protection is afforded to heterologous serotypes following infection by any one of the individual serotypes. The presence of nonneutralizing antibodies to one serotype can facilitate the occurrence of more-severe dengue hemorrhagic fever through immune enhancement upon infection with a second serotype. For this reason, the development of a safe, tetravalent vaccine to produce a balanced immune response to all four serotypes is critical. We have developed a novel approach to produce safe and effective live-attenuated vaccines for DENV and other insect-borne viruses. Host range (HR) mutants of each DENV serotype were created by truncating transmembrane domain 1 of the E protein and selecting for strains of DENV that replicated well in insect cells but not mammalian cells. These vaccine strains were tested for immunogenicity in African green monkeys (AGMs). No vaccine-related adverse events occurred. The vaccine strains were confirmed to be attenuated in vivo by infectious center assay (ICA). Analysis by 50% plaque reduction neutralization test (PRNT50) established that by day 62 postvaccination, 100% of animals seroconverted to DENV-1, -2, -3, and -4. Additionally, the DENV HR tetravalent vaccine (HR-Tet) showed a tetravalent anamnestic immune response in 100% (16/16) of AGMs after challenge with wild-type (WT) DENV strains. IMPORTANCE We have generated a live attenuated viral (LAV) vaccine capable of eliciting a strong immune response in African green monkeys (AGMs) in a single dose. This vaccine is delivered by injecting one of four attenuated serotypes into each limb of the animal. 100% of animals given the vaccine generated antibodies against all 4 serotypes, and this

  9. Live attenuated tetravalent dengue virus host range vaccine is immunogenic in African green monkeys following a single vaccination.

    Science.gov (United States)

    Briggs, Caitlin M; Smith, Katherine M; Piper, Amanda; Huitt, Emerson; Spears, Carla J; Quiles, Michelle; Ribeiro, Mariana; Thomas, Malcolm E; Brown, Dennis T; Hernandez, Raquel

    2014-06-01

    The causative agent of dengue fever, dengue virus (DENV), is transmitted by mosquitoes, and as distribution of these insects has expanded, so has dengue-related disease. DENV is a member of the Flaviviridae family and has 4 distinct serotypes (DENV-1, -2, -3, and -4). No lasting cross protection is afforded to heterologous serotypes following infection by any one of the individual serotypes. The presence of nonneutralizing antibodies to one serotype can facilitate the occurrence of more-severe dengue hemorrhagic fever through immune enhancement upon infection with a second serotype. For this reason, the development of a safe, tetravalent vaccine to produce a balanced immune response to all four serotypes is critical. We have developed a novel approach to produce safe and effective live-attenuated vaccines for DENV and other insect-borne viruses. Host range (HR) mutants of each DENV serotype were created by truncating transmembrane domain 1 of the E protein and selecting for strains of DENV that replicated well in insect cells but not mammalian cells. These vaccine strains were tested for immunogenicity in African green monkeys (AGMs). No vaccine-related adverse events occurred. The vaccine strains were confirmed to be attenuated in vivo by infectious center assay (ICA). Analysis by 50% plaque reduction neutralization test (PRNT50) established that by day 62 postvaccination, 100% of animals seroconverted to DENV-1, -2, -3, and -4. Additionally, the DENV HR tetravalent vaccine (HR-Tet) showed a tetravalent anamnestic immune response in 100% (16/16) of AGMs after challenge with wild-type (WT) DENV strains. We have generated a live attenuated viral (LAV) vaccine capable of eliciting a strong immune response in African green monkeys (AGMs) in a single dose. This vaccine is delivered by injecting one of four attenuated serotypes into each limb of the animal. 100% of animals given the vaccine generated antibodies against all 4 serotypes, and this response was found to be

  10. 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).

  11. Genetic Profile Variation in Vaccine Strains and Clinical Isolates of Bordetella pertussis Recovered from Iranian Patients

    OpenAIRE

    Haghighi, Faezeh; Shahcheraghi, Fereshteh; Abbasi, Ebrahim; Eshraghi, Seyed Saeed; Zeraati, Hojjat; Mousavi, Seyed Ali Javad; Asgarian-Omran, Hossein; Douraghi, Masoumeh; Shokri, Fazel

    2014-01-01

    Background Re-emergence of pertussis has been reported in Iran despite a high rate of vaccination coverage. Low efficacy of the vaccine might be due to the genetic divergence between clinical versus vaccine strains. In the current study, the genetic profiles of clinical isolates and vaccine strains of Bordetella pertussis (B. pertussis) were assessed by using Pulsed Field Gel Electrophoresis (PFGE). Methods Following phenotypic and molecular identification of isolates, XbaI-digested genomic D...

  12. Single Dose Trivalent Vesiculovax Vaccine Protects Macaques from Lethal Ebolavirus and Marburgvirus Challenge.

    Science.gov (United States)

    Matassov, Demetrius; Mire, Chad E; Latham, Theresa; Geisbert, Joan B; Xu, Rong; Ota-Setlik, Ayuko; Agans, Krystle N; Kobs, Dean J; Wendling, Morgan Q S; Burnaugh, Amanda; Rudge, Thomas L; Sabourin, Carol L; Egan, Michael A; Clarke, David K; Geisbert, Thomas W; Eldridge, John H

    2017-11-15

    Previous studies demonstrated that a single intramuscular (IM) dose of an attenuated vesicular stomatitis virus vector (Vesiculovax™, rVSV-N4CT1) expressing the glycoprotein (GP) from the Mayinga strain of Zaire ebolavirus (EBOV) protected nonhuman primates (NHP) from lethal challenge with EBOV Kikwit and Makona strains. Here we studied the immunogenicity of an expanded range of attenuated rVSV vectors expressing filovirus GP in mice. Based on data from those studies an optimal attenuated tri-valent rVSV vector formulation was identified which included rVSV vectors expressing EBOV , Sudan ebolavirus (SUDV) or Angola strain of Marburg marburgvirus (MARV) GPs. NHPs were then vaccinated with a single dose of the tri-valent formulation, followed by lethal challenge 28 days later with each of the three corresponding filoviruses. At day 14 post vaccination, a serum IgG response specific for all three GPs was detected in all vaccinated macaques. A modest and balanced cell-mediated immune response specific for each GP protein was also detected in a majority of vaccinated macaques. No matter the level of total GP-specific immune response detected post vaccination, all vaccinated macaques were protected from disease and death following lethal challenge with each of the three filoviruses. These findings indicate that vaccination with a single dose of attenuated rVSV-N4CT1 vectors each expressing a single filovirus GP may provide protection against those filoviruses most commonly responsible for outbreaks of hemorrhagic fever in sub-Saharan Africa. IMPORTANCE The West African Ebola Zaire outbreak in 2013 showed that this disease was not only a regional concern, but a worldwide problem and highlighted the need for a safe and efficacious vaccine to be administered to the populace. However, other endemic pathogens like Ebola Sudan and Marburg also pose an important health risk to the public and therefore require development of a vaccine prior to the occurrence of an outbreak

  13. A single or multistage mycobacterium avium subsp. paratuberculosis subunit vaccine

    DEFF Research Database (Denmark)

    2014-01-01

    The present invention provides one or more immunogenic polypeptides for use in a preventive or therapeutic vaccine against latent or active infection in a human or animal caused by a Mycobacterium species, e.g. Mycobacterium avium subsp. paratuberculosis. Furthermore a single or multi-phase vaccine...... comprising the one or more immunogenic polypeptides is provided for administration for the prevention or treatment of infection with a Mycobacterium species, e.g. Mycobacterium avium subsp. paratuberculosis. Additionally, nucleic acid vaccines, capable of in vivo expression of the multi-phase vaccine...

  14. Implementation research: reactive mass vaccination with single-dose oral cholera vaccine, Zambia.

    Science.gov (United States)

    Poncin, Marc; Zulu, Gideon; Voute, Caroline; Ferreras, Eva; Muleya, Clara Mbwili; Malama, Kennedy; Pezzoli, Lorenzo; Mufunda, Jacob; Robert, Hugues; Uzzeni, Florent; Luquero, Francisco J; Chizema, Elizabeth; Ciglenecki, Iza

    2018-02-01

    To describe the implementation and feasibility of an innovative mass vaccination strategy - based on single-dose oral cholera vaccine - to curb a cholera epidemic in a large urban setting. In April 2016, in the early stages of a cholera outbreak in Lusaka, Zambia, the health ministry collaborated with Médecins Sans Frontières and the World Health Organization in organizing a mass vaccination campaign, based on single-dose oral cholera vaccine. Over a period of 17 days, partners mobilized 1700 health ministry staff and community volunteers for community sensitization, social mobilization and vaccination activities in 10 townships. On each day, doses of vaccine were delivered to vaccination sites and administrative coverage was estimated. Overall, vaccination teams administered 424 100 doses of vaccine to an estimated target population of 578 043, resulting in an estimated administrative coverage of 73.4%. After the campaign, few cholera cases were reported and there was no evidence of the disease spreading within the vaccinated areas. The total cost of the campaign - 2.31 United States dollars (US$) per dose - included the relatively low cost of local delivery - US$ 0.41 per dose. We found that an early and large-scale targeted reactive campaign using a single-dose oral vaccine, organized in response to a cholera epidemic within a large city, to be feasible and appeared effective. While cholera vaccines remain in short supply, the maximization of the number of vaccines in response to a cholera epidemic, by the use of just one dose per member of an at-risk community, should be considered.

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

    Directory of Open Access Journals (Sweden)

    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

  16. 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

  17. [The difference in specific humoral immune responses induced with the attenuated equine infectious anemia vaccine strain and virulent strain.].

    Science.gov (United States)

    Zhu, Zhen-Ying; Lin, Yue-Zhi; Wang, Yu-Hong; Zhao, Li-Ping; Zhu, Yuan-Mao; Zhou, Jian-Hua

    2009-12-01

    To disclose the potential roles of humoral immune response in the EIAV vaccine-induced protective immunity. In this study, major parameters of humoral immunity be compared between horses inoculated with the EIAV vaccine strain and the pathogenic virulent strain. Experimental horses were randomly assigned into the group inoculated with the vaccine strain EIAV(DLV); (the vaccinated group) and the group inoculated with sub-morbigenous dose of virulent strain EIAV(Liao); (the inapparent infection group). Humoral immunity parameters, including binding endpoint titer and avidity index of antibodies to the envelop protein (Env) and the capsid protein (P26), and the conformation-dependent index of the Env antibody, were assayed and compared between these two groups by using ELISA. Neutralizing antibodies to the EIAV vaccine strain and a pathogenic strain were simultaneously detected by using plaque forming unite assay (PFU) and reverse transcriptase activity assay, respectively. In general, all humoral parameters increased with a time-dependent manner in both the vaccinated and the inapparent infection group. However, significantly higher antibody activities for P26 binding endpoint titer and Env avidity index were detected in the vaccinated group within 2 months post infection (Pinfection group throughout the entire observation period (Pinfected horses (P<0.01 for EIAV(FDDV); and P<0.05 for EIAV(DLV34);). Statistically significant differences in EIAV-specific binding antibodies and the neutralizing antibody are detected between animals induced with the EIAV vaccine strain and the virulent strain. Importantly, the significantly early and strong responses in the neutralizing antibody and the conformation-dependent Env antibody induced by the vaccine implicate special roles these antibodies playing in EIAV vaccine-induced immune protection.

  18. Complete Genome Sequences of Five Bluetongue Virus (BTV) Vaccine Strains from a Commercial Live Attenuated Vaccine, a BTV-4 Field Strain from South Africa, and a Reassortant Strain Isolated from Experimentally Vaccinated Cattle

    Science.gov (United States)

    Coetzee, Peter; le Grange, Misha; Venter, Estelle H.

    2016-01-01

    This is a report of the complete genome sequences of plaque-selected isolates of each of the five virus strains included in a South African commercial trivalent bluetongue virus (BTV) attenuated live virus vaccine, a BTV-4 field strain isolated from Rustenburg, South Africa, in 2011, and a bluetongue reassortant (bluetongue virus 4 strain 4/O. aries-tc/ZAF/11/OBP-115) isolated from experimentally vaccinated cattle. Full-genome sequencing and phylogenetic analyses show that the bluetongue virus 9 strain 9/B. taurus-tc/ZAF/15/Onderstepoort_B02b is a reassortant virus containing segments from both BTV-9 and BTV-8. PMID:27340051

  19. Vaccination with Vesicular Stomatitis Virus-Vectored Chimeric Hemagglutinins Protects Mice against Divergent Influenza Virus Challenge Strains.

    Science.gov (United States)

    Ryder, Alex B; Nachbagauer, Raffael; Buonocore, Linda; Palese, Peter; Krammer, Florian; Rose, John K

    2015-12-16

    Seasonal influenza virus infections continue to cause significant disease each year, and there is a constant threat of the emergence of reassortant influenza strains causing a new pandemic. Available influenza vaccines are variably effective each season, are of limited scope at protecting against viruses that have undergone significant antigenic drift, and offer low protection against newly emergent pandemic strains. "Universal" influenza vaccine strategies that focus on the development of humoral immunity directed against the stalk domains of the viral hemagglutinin (HA) show promise for protecting against diverse influenza viruses. Here, we describe such a strategy that utilizes vesicular stomatitis virus (VSV) as a vector for chimeric hemagglutinin (cHA) antigens. This vaccination strategy is effective at generating HA stalk-specific, broadly cross-reactive serum antibodies by both intramuscular and intranasal routes of vaccination. We show that prime-boost vaccination strategies provide protection against both lethal homologous and heterosubtypic influenza challenge and that protection is significantly improved with intranasal vaccine administration. Additionally, we show that vaccination with VSV-cHAs generates greater stalk-specific and cross-reactive serum antibodies than does vaccination with VSV-vectored full-length HAs, confirming that cHA-based vaccination strategies are superior at generating stalk-specific humoral immunity. VSV-vectored influenza vaccines that express chimeric hemagglutinin antigens offer a novel means for protecting against widely diverging influenza viruses. Universal influenza vaccination strategies should be capable of protecting against a wide array of influenza viruses, and we have developed such an approach utilizing a single viral vector system. The potent antibody responses that these vaccines generate are shown to protect mice against lethal influenza challenges with highly divergent viruses. Notably, intranasal vaccination

  20. Oral vaccination of badgers (Meles meles) against tuberculosis: comparison of the protection generated by BCG vaccine strains Pasteur and Danish.

    Science.gov (United States)

    Murphy, Denise; Costello, Eamon; Aldwell, Frank E; Lesellier, Sandrine; Chambers, Mark A; Fitzsimons, Tara; Corner, Leigh A L; Gormley, Eamonn

    2014-06-01

    Vaccination of badgers by the subcutaneous, mucosal and oral routes with the Pasteur strain of Mycobacterium bovis bacille Calmette-Guérin (BCG) has resulted in significant protection against experimental infection with virulent M. bovis. However, as the BCG Danish strain is the only commercially licensed BCG vaccine for use in humans in the European Union it is the vaccine of choice for delivery to badger populations. As all oral vaccination studies in badgers were previously conducted using the BCG Pasteur strain, this study compared protection in badgers following oral vaccination with the Pasteur and the Danish strains. Groups of badgers were vaccinated orally with 10(8) colony forming units (CFU) BCG Danish 1331 (n = 7 badgers) or 10(8) CFU BCG Pasteur 1173P2 (n = 6). Another group (n = 8) served as non-vaccinated controls. At 12 weeks post-vaccination, the animals were challenged by the endobronchial route with 6 × 10(3) CFU M. bovis, and at 15 weeks post-infection, all of the badgers were euthanased. Vaccination with either BCG strain provided protection against challenge compared with controls. The vaccinated badgers had significantly fewer sites with gross pathology and significantly lower gross pathological severity scores, fewer sites with histological lesions and fewer sites of infection, significantly lower bacterial counts in the thoracic lymph node, and lower bacterial counts in the lungs than the control group. No differences were observed between either of the vaccine groups by any of the pathology and bacteriology measures. The ELISPOT analysis, measuring production of badger interferon - gamma (IFN-γ), was also similar across the vaccinated groups. Copyright © 2014 Elsevier Ltd. All rights reserved.

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

    Science.gov (United States)

    Gelaye, Esayas; Belay, Alebachew; Ayelet, Gelagay; Jenberie, Shiferaw; Yami, Martha; Loitsch, Angelika; Tuppurainen, Eeva; Grabherr, Reingard; Diallo, Adama; Lamien, Charles Euloge

    2015-07-01

    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. Retrospective outbreak data were compiled and isolates collected from thirteen outbreaks in small ruminants and cattle at various geographical locations and years were analyzed and compared to the vaccine strain. Isolates of GTPV and LSDV genotypes were responsible for the capripox outbreaks in small ruminants and cattle, respectively, while SPPV was absent. Pathogenic isolates collected from vaccinated cattle were identical to those from the non-vaccinated ones. The vaccine strain, genetically distinct from the outbreak isolates, was not responsible for these outbreaks. This study shows capripox to be highly significant in Ethiopia due to low performance of the local vaccine and insufficient vaccination coverage. The development of new, more efficient vaccine strains, a GTPV strain for small ruminants and a LSDV for cattle, is needed to promote the acceptance by farmers, thus contribute to better control of CaPVs in Ethiopia. Copyright © 2015 Elsevier B.V. All rights reserved.

  2. Complete Genome Sequences of Bovine Parainfluenza Virus Type 3 Strain BN-1 and Vaccine Strain BN-CE.

    Science.gov (United States)

    Ohkura, Takashi; Kokuho, Takehiro; Konishi, Misako; Kameyama, Ken-Ichiro; Takeuchi, Kaoru

    2013-01-01

    Bovine parainfluenza virus type 3 (BPIV3) is associated with upper respiratory disease in cattle in many countries. Here, we report the complete genome sequences of the BPIV3 BN-1 strain, isolated from cattle in Japan, and the BN-CE vaccine strain, derived from the BN-1 strain by passages in chicken embryo fibroblasts.

  3. Isolation of rifampicin resistant Flavobacterium psychrophilum strains and their potential as live attenuated vaccine candidates

    Science.gov (United States)

    Previous studies have demonstrated that passage of pathogenic bacteria on increasing concentrations of the antibiotic rifampicin leads to the attenuation of virulence and these resistant strains may serve as live attenuated vaccines. Two rifampicin resistant strains of Flavobacterium psychrophilum,...

  4. Genetic instability of live, attenuated human immunodeficiency virus type 1 vaccine strains

    NARCIS (Netherlands)

    Berkhout, B.; Verhoef, K.; van Wamel, J. L.; Back, N. K.

    1999-01-01

    Live, attenuated viruses have been the most successful vaccines in monkey models of human immunodeficiency virus type 1 (HIV-1) infection. However, there are several safety concerns about using such an anti-HIV vaccine in humans, including reversion of the vaccine strain to virulence and

  5. Simulating colonic survival of probiotics in single-strain products compared to multi-strain products.

    Science.gov (United States)

    Forssten, S D; Ouwehand, A C

    2017-01-01

    Background : Probiotic formulations can be single- or multi-strain. Commercially, multi-strain preparations have been suggested to have improved functionality over single-strain cultures. Probiotics are often tested as single-strain preparations but may subsequently be commercially formulated as multi-strain products. Objective : The aim of this study was to determine what happens at the site of action, the intestine, with probiotics as single- compared to multi-strain preparations. The human gastrointestinal tract contains a broad mixture of different microbes which may affect the survival of different probiotics in different ways. Design : The current study was performed to evaluate, in an in vitro colon simulation, whether probiotics influence each other's survival when they are taken as a combination of several strains (HOWARU Restore; Lactobacillus acidophilus NCFM, Lactobacillus paracasei Lpc-37, Bifidobacterium lactis Bl-04 and B. lactis Bi-07) compared to the strains as single preparations. Results : All strains could be detected after the colon simulations and there were no substantial differences in levels of the same strain when comparing single- and multi-strain products. Conclusions : It can be concluded that probiotics do not have an antagonistic effect on each other's survival when used in a multi-strain product compared to a single-strain product, at least within a microbiota in a simulated colonic environment.

  6. Safety and immunogenicity of a vaccine bait containing ERA strain of attenuated rabies virus.

    OpenAIRE

    Lawson, K F; Black, J G; Charlton, K M; Johnston, D H; Rhodes, A J

    1987-01-01

    Ninety percent of foxes fed commercial ERA vaccine in a specially designed bait developed rabies serum neutralizing antibodies. The vaccine bait did not cause clinical signs of rabies when consumed by foxes, raccoons, skunks, dogs, cats, cattle and monkeys. When presented, in the laboratory, to wild rodents of the species Microtus, Mus musculus and Peromyscus, the vaccine baits caused vaccine-induced rabies only in Mus musculus. Laboratory mice of the CD-1 and CLL strain were susceptible to v...

  7. Reduced cerebral infection of Neospora caninum in BALB/c mice vaccinated with recombinant Brucella abortus RB51 strains expressing N. caninum SRS2 and GRA7 proteins.

    Science.gov (United States)

    Vemulapalli, Ramesh; Sanakkayala, Neelima; Gulani, Jatinder; Schurig, Gerhardt G; Boyle, Stephen M; Lindsay, David S; Sriranganathan, Nammalwar

    2007-09-30

    Neospora caninum, an obligate intracellular protozoan parasite, is the causative agent of bovine neosporosis, an important disease affecting the reproductive performance of cattle worldwide. Currently there is no effective vaccine available to prevent N. caninum infection in cattle. In this study, we examined the feasibility of developing a live, recombinant N. caninum vaccine using Brucella abortus vaccine strain RB51 as the expression and delivery vector. We generated two recombinant RB51 strains each expressing SRS2 (RB51/SRS2) or GRA7 (RB51/GRA7) antigens of N. caninum. BALB/c mice immunized by single intraperitoneal inoculation of the recombinant RB51 strains developed IgG antibodies specific to the respective N. caninum antigen. In vitro stimulation of splenocytes from the vaccinated mice with specific antigen resulted in the production of interferon-gamma, but not IL-5 or IL-10, suggesting the development of a Th1 type immune response. Upon challenge with N. caninum tachyzoites, mice vaccinated with strain RB51/SRS2, but not RB51/GRA7, showed significant resistance to cerebral infection when compared to the RB51 vaccinated mice, as determined by the tissue parasite load using a real-time quantitative TaqMan assay. Interestingly, mice vaccinated with either strain RB51 or RB51/GRA7 also contained significantly lower parasite burden in their brains compared to those inoculated with saline. Mice vaccinated with strain RB51/SRS2 or RB51/GRA7 were protected to the same extent as the strain RB51 vaccinated mice against challenge with B. abortus virulent strain 2308. These results suggest that a recombinant RB51 strain expressing an appropriate protective antigen(s), such as SRS2 of N. caninum, can confer protection against both neosporosis and brucellosis.

  8. Vaxchora: A Single-Dose Oral Cholera Vaccine.

    Science.gov (United States)

    Cabrera, Adriana; Lepage, Jayne E; Sullivan, Karyn M; Seed, Sheila M

    2017-07-01

    To review trials evaluating the efficacy and safety of Vaxchora, a reformulated, single-dose, oral, lyophilized Vibrio cholerae CVD 103-HgR vaccine for the prevention of travel-related cholera caused by V cholerae serogroup O1. A literature search was conducted using MEDLINE (1946 to January week 3, 2017) and EMBASE (1996 to 2017 week 3). Keywords included oral cholera vaccine, single-dose, Vaxchora, and CVD 103-HgR. Limits included human, clinical trials published in English since 2010. ClinicalTrials.gov was used as a source for unpublished data. Additional data sources were obtained through bibliographic review of selected articles. Studies that addressed the safety and efficacy of Vaxchora, the reformulated, single-dose oral CVD 103-HgR cholera vaccine, were selected for analysis. Approval of Vaxchora, was based on efficacy of the vaccine in human trials demonstrating 90.3% protection among those challenged with V cholerae 10 days after vaccination and in immunogenicity studies with 90% systemic vibriocidal antibody conversion at 6 months after a single-dose of vaccine. Tolerability was acceptable, with the most common adverse effects reported to be fatigue, headache, and abdominal pain. Vaxchora is the only FDA-approved, single-dose oral vaccine for the prevention of cholera caused by V cholerae serogroup O1 in adult travelers from the United States going to cholera-affected areas. Safety and efficacy has not been established in children, immunocompromised persons, and pregnant or breastfeeding women or those living in cholera-endemic areas.

  9. 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.

  10. Critical site differences of fusion protein between wildtype and vaccine measles virus strains in Indonesia

    Directory of Open Access Journals (Sweden)

    Made Setiawan

    2011-06-01

    vaccine to be less effective. Objective To detennine the amino add sequence differences in critical sites of F protein in Mld type and vaccine measles virus strains in Indonesia. Methods We compared amino acid sequences of three genotypes of Mld type measles virus (02, 03 and D9 to those of the vaccine strains, CAM 70, Schwarz, and Edmonstonwt type measles virus. Resul ts Analysis showed that there were differences at FlF2 cleavage site, B cell epitopes, and H protein binding site between the CAM70 vaccine viral strains and Mld type strains. Schwarz vaccine strain differed from the wild type strains at the H protein binding site. A 03 wild type strain potential glycosylation site was also different from all other strains studied. Conclusion There were differences in the critical sites of F protein between Mld type strains and the CAM70 and Schwarz vaccine strains.

  11. The Humoral Immune Response of Elks (Cervus elaphus nelsoni) and Mice to Vaccination with Brucella abortus Strain RB51

    OpenAIRE

    Colby, Lesley A.

    1997-01-01

    Vaccine Brucella abortus strain RB51, unlike the wild strain 2308 and another vaccine strain (strain 19) does not induce anti-O-chain antibodies. An efficacious vaccine strain that fails to produce an O-chain and thus a lack of an anti-O-chain humoral response greatly simplifies identification of vaccinated versus field strain infected animals. The three primary objectives of this research were the following: 1) to develop a serological assay to detect anti-RB51 antibodies in vaccinated elk (...

  12. 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.

  13. 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.

  14. Detection and differentiation of wild-type and a vaccine strain of Streptococcus equi ssp. equi using pyrosequencing.

    Science.gov (United States)

    Livengood, Julia L; Lanka, Saraswathi; Maddox, Carol; Tewari, Deepanker

    2016-07-25

    Streptococcus equi subspecies equi (S. equi), the causative agent of strangles, is an important equine pathogen. Strangles is a highly contagious disease and a commercial modified live vaccine (MLV) is used for protection, which although effective, may also result in clinical signs of the disease. A rapid means to differentiate between the MLV and wild-type infection is crucial for quarantine release and limiting the disease spread. This study describes the use of a pyrosequencing assay targeting a single nucleotide deletion upstream of the SzPSe gene to distinguish between the wild-type and vaccine strains. A set of 96 characterized clinical specimens and isolates were tested using the assay. The assay was successful in differentiating between wild-type S. equi and the vaccine strains and in discriminating S. equi from other Streptococci. The vaccine strain was identified in 61.7% (29/47) of the strangles cases in horses with a history of MLV vaccination. Copyright © 2016 Elsevier Ltd. All rights reserved.

  15. Live Brucella abortus rough vaccine strain RB51 stimulates enhanced innate immune response in vitro compared to rough vaccine strain RB51SOD and virulent smooth strain 2308 in murine bone marrow-derived dendritic cells.

    Science.gov (United States)

    Surendran, Naveen; Hiltbold, Elizabeth M; Heid, Bettina; Sriranganathan, Nammalwar; Boyle, Stephen M; Zimmerman, Kurt L; Makris, Melissa R; Witonsky, Sharon G

    2011-01-10

    Brucella spp. are Gram-negative, coccobacillary, facultative intracellular pathogens. B. abortus strain 2308 is a pathogenic strain affecting cattle and humans. Rough B. abortus strain RB51, which lacks the O-side chain of lipopolysaccharide (LPS), is the live attenuated USDA approved vaccine for cattle in the United States. Strain RB51SOD, which overexpresses Cu-Zn superoxide dismutase (SOD), has been shown to confer better protection than strain RB51 in a murine model. Protection against brucellosis is mediated by a strong CD4+ Th(1) and CD8+ Tc(1) adaptive immune response. In order to stimulate a robust adaptive response, a solid innate immune response, including that mediated by dendritic cells, is essential. As dendritic cells (DCs) are highly susceptible to Brucella infection, it is possible that pathogenic strains could limit the innate and thereby adaptive immune response. By contrast, vaccine strains could limit or bolster the innate and subsequent adaptive immune response. Identifying how Brucella vaccines stimulate innate and adaptive immunity is critical for enhancing vaccine efficacy. The ability of rough vaccine strains RB51 and RB51SOD to stimulate DC function has not been characterized. We report that live rough vaccine strain RB51 induced significantly better (p ≤ 0.05) DC maturation and function compared to either strain RB51SOD or smooth virulent strain 2308, based on costimulatory marker expression and cytokine production. Copyright © 2010. Published by Elsevier B.V.

  16. Varicella vaccination: evidence for frequent reactivation of the vaccine strain in healthy children.

    Science.gov (United States)

    Krause, P R; Klinman, D M

    2000-04-01

    Wild-type varicella zoster virus (VZV) causes chickenpox, a common childhood illness characterized by fever and a vesicular rash and rare serious complications. Wild-type VZV persists in a latent form in the sensory ganglia, and can re-activate to cause herpes zoster. More than 10 million American children have received the live attenuated Oka strain VZV vaccine (OkaVZV) since its licensure in 1995. Pre-licensure clinical studies showed that mean serum anti-VZV levels among vaccinees continued to increase with time after vaccination. This was attributed to immunologic boosting caused by exposure to wild-type VZV in the community. Here, we examine the alternative, that large-scale asymptomatic reactivation of OkaVZV might occur in vaccinees. We analyzed serum antibody levels and infection rates for 4 years of follow-up in 4,631 children immunized with OkaVZV. Anti-VZV titers decreased over time in high-responder subjects, but rose in vaccinees with low titers. Among subjects with low anti-VZV titers, the frequency of clinical infection and immunological boosting substantially exceeded the 13%-per-year rate of exposure to wild-type varicella. These findings indicate that OkaVZV persisted in vivo and reactivated as serum antibody titers decreased after vaccination. This has salient consequences for individuals immunized with OkaVZV.

  17. Immune overload: Parental attitudes toward combination and single antigen vaccines.

    Science.gov (United States)

    Hulsey, Ella; Bland, Tami

    2015-05-21

    Parental concerns have led to a recent decline in immunization coverage, resulting in outbreaks of diseases that were once under control in the US. As the CDC vaccination schedule continues to increase in complexity, the number of required injections per office visit increases as well. Some parents perceive that there is trauma associated with the administration of multiple injections, and research shows that having multiple vaccines due in a single visit is associated with delays and lower immunization rates. Combination vaccines make vaccination more efficient by incorporating the antigens of several different diseases into a single injection, but many parents worry that they may overload the child's developing immune system and leave him or her susceptible to secondary infections. This literature review synthesizes current evidence regarding the parental fear of vaccine-induced immune system overload and the fear of vaccine-associated trauma, in an attempt to understand the scope and nature of these fears. Despite the wealth of knowledge about each of these fears individually, it is still unknown which is of greater concern and how this affects parental decision-making. Copyright © 2015 Elsevier Ltd. All rights reserved.

  18. Radioimmunoassay determination of antigenic concordance among hemagglutinins of vaccine and epidemic influenza virus strains

    Energy Technology Data Exchange (ETDEWEB)

    Blokha, V.V.; Yamnikova, S.S.; Karpovich, L.G.; Yakhno, M.A.; Zakstel' skaya, L.Ya.

    Radioimmunoassay studies were conducted on the antigenic concordance of hemagglutinin of influenza A H3N2 viruses, to determine the suitability of vaccine strains in engendering immunity against viruses circulating in nature. Specifically, the inhibition studies involved the hemagglutinins of the A/Victoria/35/72 vaccine strain, the proposed vaccine strain A/Khabarovsk/15/76, and the RK-5 recombinant strains, containing antigenic determinants of viruses isolated in the 1972-1976 epidemic period (A/Victoria/3/75, A/Leningrad/173/75, A/Victoria/112/76). The results showed that A/Victoria/35/72 is becoming less important as a vaccine, but that RK-5 and A/Khabarovsk/15/76 can provide significant immunity with respect to influenza viruses circulating in 1975-1976. These observations point to the usefulness of radioimmunoassay in assessing the suitability of influenza A viruses for vaccine production. 12 references, 2 figures.

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

    Science.gov (United States)

    1983-05-20

    previously reported auxotrophic defects causing loss of virulence in S. typhi ........................ 5 Nutritional character of wild-type S._ typhi...apparent discrepancy between our results and those of Roth proved to be a difference in the defined medium used as base for tests of nutritional ...carboxylase aspartate must serve as precursor of several aminoacids and of purines,etc, as well as of aspartate in protein). Strain 20063 after single

  20. A single or multistage mycobacterium avium subsp. paratuberculosis subunit vaccine

    DEFF Research Database (Denmark)

    2014-01-01

    The present invention provides one or more immunogenic polypeptides for use in a preventive or therapeutic vaccine against latent or active infection in a human or animal caused by a Mycobacterium species, e.g. Mycobacterium avium subsp. paratuberculosis. Furthermore a single or multi-phase vaccine...... comprising the one or more immunogenic polypeptides is provided for administration for the prevention or treatment of infection with a Mycobacterium species, e.g. Mycobacterium avium subsp. paratuberculosis. Additionally, nucleic acid vaccines, capable of in vivo expression of the multi-phase vaccine...... comprising the one or more immunogenic polypeptides, is provided for prevention or treatment of infection with a Mycobacterium species, e.g. Mycobacterium avium subsp. paratuberculosis....

  1. Serotype diversity and reassortment between human and animal rotavirus strains: implications for rotavirus vaccine programs.

    Science.gov (United States)

    Gentsch, Jon R; Laird, Ashley R; Bielfelt, Brittany; Griffin, Dixie D; Banyai, Krisztian; Ramachandran, Madhu; Jain, Vivek; Cunliffe, Nigel A; Nakagomi, Osamu; Kirkwood, Carl D; Fischer, Thea K; Parashar, Umesh D; Bresee, Joseph S; Jiang, Baoming; Glass, Roger I

    2005-09-01

    The development of rotavirus vaccines that are based on heterotypic or serotype-specific immunity has prompted many countries to establish programs to assess the disease burden associated with rotavirus infection and the distribution of rotavirus strains. Strain surveillance helps to determine whether the most prevalent local strains are likely to be covered by the serotype antigens found in current vaccines. After introduction of a vaccine, this surveillance could detect which strains might not be covered by the vaccine. Almost 2 decades ago, studies demonstrated that 4 globally common rotavirus serotypes (G1-G4) represent >90% of the rotavirus strains in circulation. Subsequently, these 4 serotypes were used in the development of reassortant vaccines predicated on serotype-specific immunity. More recently, the application of reverse-transcription polymerase chain reaction genotyping, nucleotide sequencing, and antigenic characterization methods has confirmed the importance of the 4 globally common types, but a much greater strain diversity has also been identified (we now recognize strains with at least 42 P-G combinations). These studies also identified globally (G9) or regionally (G5, G8, and P2A[6]) common serotype antigens not covered by the reassortant vaccines that have undergone efficacy trials. The enormous diversity and capacity of human rotaviruses for change suggest that rotavirus vaccines must provide good heterotypic protection to be optimally effective.

  2. Zika virus protection by a single low-dose nucleoside-modified mRNA vaccination.

    Science.gov (United States)

    Pardi, Norbert; Hogan, Michael J; Pelc, Rebecca S; Muramatsu, Hiromi; Andersen, Hanne; DeMaso, Christina R; Dowd, Kimberly A; Sutherland, Laura L; Scearce, Richard M; Parks, Robert; Wagner, Wendeline; Granados, Alex; Greenhouse, Jack; Walker, Michelle; Willis, Elinor; Yu, Jae-Sung; McGee, Charles E; Sempowski, Gregory D; Mui, Barbara L; Tam, Ying K; Huang, Yan-Jang; Vanlandingham, Dana; Holmes, Veronica M; Balachandran, Harikrishnan; Sahu, Sujata; Lifton, Michelle; Higgs, Stephen; Hensley, Scott E; Madden, Thomas D; Hope, Michael J; Karikó, Katalin; Santra, Sampa; Graham, Barney S; Lewis, Mark G; Pierson, Theodore C; Haynes, Barton F; Weissman, Drew

    2017-03-09

    Zika virus (ZIKV) has recently emerged as a pandemic associated with severe neuropathology in newborns and adults. There are no ZIKV-specific treatments or preventatives. Therefore, the development of a safe and effective vaccine is a high priority. Messenger RNA (mRNA) has emerged as a versatile and highly effective platform to deliver vaccine antigens and therapeutic proteins. Here we demonstrate that a single low-dose intradermal immunization with lipid-nanoparticle-encapsulated nucleoside-modified mRNA (mRNA-LNP) encoding the pre-membrane and envelope glycoproteins of a strain from the ZIKV outbreak in 2013 elicited potent and durable neutralizing antibody responses in mice and non-human primates. Immunization with 30 μg of nucleoside-modified ZIKV mRNA-LNP protected mice against ZIKV challenges at 2 weeks or 5 months after vaccination, and a single dose of 50 μg was sufficient to protect non-human primates against a challenge at 5 weeks after vaccination. These data demonstrate that nucleoside-modified mRNA-LNP elicits rapid and durable protective immunity and therefore represents a new and promising vaccine candidate for the global fight against ZIKV.

  3. Strain predominance following exposure of vaccinated and naive pregnant gilts to multiple strains of porcine reproductive and respiratory syndrome virus

    OpenAIRE

    Lager, Kelly M.; Mengeling, William L.; Wesley, Ronald D.

    2003-01-01

    Two studies were performed in order to test the relative ability of different strains of porcine reproductive and respiratory syndrome virus (PRRSV) to replicate and cross the placental barrier in pregnant gilts. Study 1 comprised 6 nonvaccinated gilts. Study 2 comprised 8 nonvaccinated gilts and 12 gilts that were vaccinated twice before conception. On, or about, gestation day 90 all gilts were simultaneously exposed to 20 field strains of PRRSV (all strains were distinguishable by restricti...

  4. Optimization and Characterization of Candidate Strain for Coxsackievirus A16 Inactivated Vaccine

    Directory of Open Access Journals (Sweden)

    Jingliang Li

    2015-07-01

    Full Text Available Coxsackievirus A16 (CA16 and enterovirus 71 (EV71, both of which can cause hand, foot and mouth disease (HFMD, are responsible for large epidemics in Asian and Pacific areas. Although inactivated EV71 vaccines have completed testing in phase III clinical trials in Mainland China, CA16 vaccines are still under development. A Vero cell-based inactivated CA16 vaccine was developed by our group. Screening identified a CA16 vaccine strain (CC024 isolated from HFMD patients, which had broad cross-protective abilities and satisfied all requirements for vaccine production. Identification of the biological characteristics showed that the CA16CC024 strain had the highest titer (107.5 CCID50/mL in Vero cells, which would benefit the development of an EV71/CA16 divalent vaccine. A potential vaccine manufacturing process was established, including the selection of optimal time for virus harvesting, membrane for diafiltration and concentration, gel-filtration chromatography for the down-stream virus purification and virus inactivation method. Altogether, the analyses suggested that the CC-16, a limiting dilution clone of the CC024 strain, with good genetic stability, high titer and broad-spectrum immunogenicity, would be the best candidate strain for a CA16 inactivated vaccine. Therefore, our study provides valuable information for the development of a Vero cell-based CA16 or EV71-CA16 divalent inactivated vaccine.

  5. 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

    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...

  6. Genomic Fingerprinting of the Vaccine Strain of Clostridium Tetani by Restriction Fragment Length Polymorphism Technique

    Directory of Open Access Journals (Sweden)

    Naser Harzandi

    2013-05-01

    Full Text Available Background: Clostridium tetani or Nicolaier’s bacillus is an obligatory anaerobic, Gram-positive, movable with terminal or sub terminal spore. The chromosome of C. tetani contains 2,799,250 bp with a G+C content of 28.6%. The aim of this study was identification and genomic fingerprinting of the vaccine strain of C. tetani.Materials and Methods: The vaccine strain of C. tetani was provided by Razi Vaccine and Serum Research Institute. The seeds were inoculated into Columbia blood agar and grown for 72 h and transferred to the thioglycolate broth medium for further 36 h culturing. The cultures were incubated at 35ºC in anaerobic conditions. DNA extraction with phenol/ chloroform method was performed. After extraction, the consistency of DNA was assayed. Next, the vaccine strain was digested using pvuII enzyme and incubated at 37ºC for overnight. The digested DNA was gel-electrophoresed by 1% agarose for a short time. Then, the gel was studied with Gel Doc system and transferred to Hybond N+membrane using standard DNA blotting techniques.Results: The vaccine strain of C. tetani genome was fingerprinted by RFLP technique. Our preliminary results showed no divergence exists in the vaccine strain used for the production tetanus toxoid during the periods of 1990-2011.Conclusion: Observation suggests that there is lack of significant changes in RFLP genomic fingerprinting profile of the vaccine strain. Therefore, this strain did not lose its efficiency in tetanus vaccine production. RFLP analysis is worthwhile in investigating the nature of the vaccine strain C. tetani.

  7. Brucella abortus strain RB51 vaccine: immune response after calfhood vaccination and field investigation in Italian cattle population.

    Science.gov (United States)

    Tittarelli, Manuela; Bonfini, Barbara; De Massis, Fabrizio; Giovannini, Armando; Di Ventura, Mauro; Nannini, Donatella; Caporale, Vincenzo

    2008-01-01

    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.

  8. 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.

  9. 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.

  10. 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; Mitchell, Emily; Venter, Estelle H.

    2017-01-01

    ABSTRACT 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. PMID:28684581

  11. 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.

  12. Safety and immunogenicity of Brucella abortus strain RB51 vaccine in cross bred cattle calves in India.

    Science.gov (United States)

    Singh, Rashmi; Basera, Sanjay Singh; Tewari, Kamal; Yadav, Shweta; Joshi, Sumit; Singh, Brajesh; Mukherjee, Falguni

    2012-03-01

    Safety and immunogenicity of Brucella abortus RB51 vaccine has been evaluated in an organised dairy farm in India. All the cattle (r = 29) vaccinated with strain RB51 'responded' to the vaccine as demonstrated by iELISA using acetone killed strain RB51 antigen. The percentage responders at day 35, 60 and 90 post vaccination were 100%, 95% and 20%, respectively. Strain RB51 was able to elicit a good IFN-gamma response from vaccinated animals. The post-vaccination time point analysis indicated that the cumulative IFN-gamma response of whole blood from vaccinates stimulated with heat killed RB51 antigen was elicited in 80% of calves at 60 days post vaccination. Absence of strain RB51 in the secretions and excretion and lack of local or systemic reaction indicated the safety of the vaccine.

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

    Science.gov (United States)

    Schmitt, Deanna M; O'Dee, Dawn M; Horzempa, Joseph; Carlson, Paul E; Russo, Brian C; Bales, Jacqueline M; Brown, Matthew J; Nau, Gerard J

    2012-01-01

    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.

  14. 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.

  15. Controlling antimicrobial resistance through targeted, vaccine-induced replacement of strains.

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    Yonas I Tekle

    Full Text Available Vaccination has proven effective in controlling many infectious diseases. However, differential effectiveness with regard to pathogen genotype is a frequent reason for failures in vaccine development. Often, insufficient immune response is induced to prevent infection by the diversity of existing serotypes present in pathogenic populations of bacteria. These vaccines that target a too narrow spectrum of serotypes do not offer sufficient prevention of infections, and can also lead to undesirable strain replacements. Here, we examine a novel idea to specifically exploit the narrow spectrum coverage of some vaccines to combat specific, emerging multi- and pan-resistant strains of pathogens. Application of a narrow-spectrum vaccine could serve to prevent infections by some strains that are hard to treat, rather than offer the vaccinated individual protection against infections by the pathogenic species as such. We suggest that vaccines targeted to resistant serotypes have the potential to become important public health tools, and would represent a new approach toward reducing the burden of particular multi-resistant strains occurring in hospitals. Vaccines targeting drug-resistant serotypes would also be the first clinical intervention with the potential to drive the evolution of pathogenic populations toward drug-sensitivity. We illustrate the feasibility of this approach by modeling a hypothetical vaccine that targets a subset of methicillin-resistant Staphylococcus aureus (MRSA genotypes, in combination with drug treatment targeted at drug-sensitive genotypes. We find that a combined intervention strategy can limit nosocomial outbreaks, even when vaccine efficacy is imperfect. The broader utility of vaccine-based resistance control strategies should be further explored taking into account population structure, and the resistance and transmission patterns of the pathogen considered.

  16. Progress towards Rapid Detection of Measles Vaccine Strains: a Tool To Inform Public Health Interventions.

    Science.gov (United States)

    Hacker, Jill K

    2017-03-01

    Rapid differentiation of vaccine from wild-type strains in suspect measles cases is a valuable epidemiological tool that informs the public health response to this highly infectious disease. Few public health laboratories sequence measles virus-positive specimens to determine genotype, and the vaccine-specific real-time reverse transcriptase PCR (rRT-PCR) assay described by F. Roy et al. (J. Clin. Microbiol. 55:735-743, 2017, https://doi.org/10.1128/JCM.01879-16) offers a rapid, easily adoptable method to identify measles vaccine strains in suspect cases. Copyright © 2017 American Society for Microbiology.

  17. Characterization of CHAT and Cox type 1 live-attenuated poliovirus vaccine strains.

    Science.gov (United States)

    Martín, Javier; Minor, Philip D

    2002-06-01

    CHAT and Cox type 1 live-attenuated poliovirus strains were developed in the 1950s to be used as vaccines for humans. This paper describes their characterization with respect to virulence, sensitivity for growth at high temperatures, and complete nucleotide and amino acid sequences. The results are compared to those for their common parental wild virus, the Mahoney strain, and to those for two other poliovirus strains derived from Mahoney, the Sabin 1 vaccine strain and the mouse-adapted LS-a virus. Analysis of four isolates from cases of vaccine-associated paralytic poliomyelitis related to the CHAT vaccine revealed genetic and phenotypic properties of the CHAT strain following replication in the human gut. CHAT-VAPP strain 134 contained a genome highly evolved from that of CHAT (1.1% nucleotide differences), suggesting long-term circulation of a vaccine-derived strain in the human population. The molecular mechanisms of attenuation and evolution of poliovirus in humans are discussed in the context of the global polio eradication initiative.

  18. Monitoring the long-term molecular epidemiology of the pneumococcus and detection of potential 'vaccine escape' strains.

    Directory of Open Access Journals (Sweden)

    Gagan A Pandya

    2011-01-01

    Full Text Available While the pneumococcal protein conjugate vaccines reduce the incidence in invasive pneumococcal disease (IPD, serotype replacement remains a major concern. Thus, serotype-independent protection with vaccines targeting virulence genes, such as PspA, have been pursued. PspA is comprised of diverse clades that arose through recombination. Therefore, multi-locus sequence typing (MLST-defined clones could conceivably include strains from multiple PspA clades. As a result, a method is needed which can both monitor the long-term epidemiology of the pneumococcus among a large number of isolates, and analyze vaccine-candidate genes, such as pspA, for mutations and recombination events that could result in 'vaccine escape' strains.We developed a resequencing array consisting of five conserved and six variable genes to characterize 72 pneumococcal strains. The phylogenetic analysis of the 11 concatenated genes was performed with the MrBayes program, the single nucleotide polymorphism (SNP analysis with the DNA Sequence Polymorphism program (DnaSP, and the recombination event analysis with the recombination detection package (RDP.The phylogenetic analysis correlated with MLST, and identified clonal strains with unique PspA clades. The DnaSP analysis correlated with the serotype-specific diversity detected using MLST. Serotypes associated with more than one ST complex had a larger degree of sequence polymorphism than a serotype associated with one ST complex. The RDP analysis confirmed the high frequency of recombination events in the pspA gene.The phylogenetic tree correlated with MLST, and detected multiple PspA clades among clonal strains. The genetic diversity of the strains and the frequency of recombination events in the mosaic gene, pspA were accurately assessed using the DnaSP and RDP programs, respectively. These data provide proof-of-concept that resequencing arrays could play an important role within research and clinical laboratories in both

  19. Efficacy of marker vaccine candidate CP7 E2alf in piglets with maternally derived C-strain antibodies

    DEFF Research Database (Denmark)

    Rangelova, Desislava Yordanova; Nielsen, Jens; Strandbygaard, Bertel

    2012-01-01

    Marker vaccines offer the possibility to differentiate classical swine fever (CSF) infected from CSF vaccinated animals based on serology and their implementation will ensure free trade with pigs. Therefore, new generations of promising marker vaccines have been developed, among them the chimeric...... vaccine CP7_E2alf. However, in populations previously vaccinated with live attenuated vaccines like the C-strain, passive immunity through maternal antibodies can interfere with efficacy of CP7_E2alf vaccination. Therefore, the efficacy of CP7_E2alf was examined in piglets from sows vaccinated once...

  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. Parenteral vaccination of domestic pigs with Brucella abortus strain RB51.

    Science.gov (United States)

    Stoffregen, William C; Olsen, Steven C; Bricker, Betsy J

    2006-10-01

    To determine the immunogenicity and efficacy of Brucella abortus strain RB51 (SRB51) as a vaccine in domestic pigs. Sixty-eight 6-week-old crossbred domestic pigs and twenty-four 4-month-old gilts. In experiment 1, pigs were vaccinated IM (n = 51) with 2 x 10(10) CFUs of SRB51 or sham inoculated (17). Periodic blood samples were obtained to perform blood cultures, serologic evaluations, and cell-mediated immunity assays. Necropsies were performed at selected times between weeks 1 and 23 after vaccination to determine vaccine clearance. In experiment 2, gilts were similarly vaccinated (n = 18) or sham inoculated (8) and similar samples were obtained after vaccination. Gilts were bred and challenged conjunctivally with 5.0 x 10(7) CFUs of virulent Brucella suis strain 3B. Necropsies were performed on gilts and on fetuses or neonates after abortion or parturition, respectively. Bacterial cultures and serologic evaluations were performed on samples obtained at necropsy to determine vaccine efficacy. Humoral and cell-mediated immune responses did not differ between vaccinates and controls. After vaccination, SRB51 was not isolated from blood cultures of either group and was isolated from lymphoid tissues of 3 pigs at 2 weeks (n = 2) and 4 weeks (1) after vaccination. No differences were found in isolation of B suis or in seroconversion between vaccinated and control gilts and between their neonates or aborted fetuses. Parenteral vaccination with SRB51 does not induce humoral or cell-mediated immune responses. Vaccination with SRB51 did not protect gilts or their neonates and fetuses from virulent challenge with B suis.

  2. Efficacy of strain RB51 vaccine in heifers against experimental brucellosis.

    Science.gov (United States)

    Poester, Fernando P; Gonçalves, Vítor S P; Paixão, Tatiane A; Santos, Renato L; Olsen, Steven C; Schurig, Gerhardt G; Lage, Andrey P

    2006-06-19

    With the goal of providing an additional tool for controlling bovine brucellosis in Brazil and evaluating the full calf dose in adult cattle, the efficacy of the rough Brucella abortus strain RB51 vaccine was tested in heifers. Thirty-three females of approximately 24 months of age were divided in two groups: one group (n=20) received the RB51 vaccine and the other group (n=13) were used as non-vaccinated control. Animals in the vaccinated group were split in two sub-groups. One sub-group (n=12) was vaccinated subcutaneously with 1.5x10(10) colony forming units (CFU) of RB51 at Day 0 of the experiment and the other sub-group (n=8) was vaccinated subcutaneously with 1.6x10(10) CFU of RB51 at 60 days of gestation (Day 260 of the experiment). All cattle were challenged between 6 and 7 months of pregnancy with 3x10(8) CFU of the virulent strain 2308 of B. abortus by the conjunctival route. Vaccination with RB51 vaccine did not result in the production of any antibodies against the O-side chain of lipopolysaccharide (LPS), as measured by conventional serological tests (rose bengal plate agglutination test (RBPAT), standard tube agglutination test (STAT), and 2-mercaptoethanol test (2ME)). A total of 25% cumulative incidence of abortions was found in the vaccinated group, whereas in the control group the cumulative incidence was 62%. B. abortus RB51 was not isolated from any sample, and no abortions were produced by RB51 vaccination of females at 60 days of pregnancy. The results indicate that vaccination with RB51 prevented 59.4% of abortions, 58.6% of cow infections, and 61.0% of fetal infections. The relative risk (RR) revealed that non-vaccinated animals have 2.462 (95% CI 1.029-5.889) times higher risk of aborting than RB51-vaccinated animals.

  3. 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

  4. 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.

  5. Pandemic influenza A virus codon usage revisited: biases, adaptation and implications for vaccine strain development

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    Goñi Natalia

    2012-11-01

    Full Text Available Abstract Background Influenza A virus (IAV is a member of the family Orthomyxoviridae and contains eight segments of a single-stranded RNA genome with negative polarity. The first influenza pandemic of this century was declared in April of 2009, with the emergence of a novel H1N1 IAV strain (H1N1pdm in Mexico and USA. Understanding the extent and causes of biases in codon usage is essential to the understanding of viral evolution. A comprehensive study to investigate the effect of selection pressure imposed by the human host on the codon usage of an emerging, pandemic IAV strain and the trends in viral codon usage involved over the pandemic time period is much needed. Results We performed a comprehensive codon usage analysis of 310 IAV strains from the pandemic of 2009. Highly biased codon usage for Ala, Arg, Pro, Thr and Ser were found. Codon usage is strongly influenced by underlying biases in base composition. When correspondence analysis (COA on relative synonymous codon usage (RSCU is applied, the distribution of IAV ORFs in the plane defined by the first two major dimensional factors showed that different strains are located at different places, suggesting that IAV codon usage also reflects an evolutionary process. Conclusions A general association between codon usage bias, base composition and poor adaptation of the virus to the respective host tRNA pool, suggests that mutational pressure is the main force shaping H1N1 pdm IAV codon usage. A dynamic process is observed in the variation of codon usage of the strains enrolled in these studies. These results suggest a balance of mutational bias and natural selection, which allow the virus to explore and re-adapt its codon usage to different environments. Recoding of IAV taking into account codon bias, base composition and adaptation to host tRNA may provide important clues to develop new and appropriate vaccines.

  6. 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...

  7. Co-transmission of the non-transmissible South African Babesia bovis S24 vaccine strain during mixed infection with a field isolate.

    Science.gov (United States)

    Combrink, M P; Troskie, P C; de Klerk, D G; Pienaar, R; Latif, A A; Mans, B J

    2015-03-01

    The South African Babesia bovis live blood vaccine, originating from a field isolate attenuated by 23 serial syringe passages in splenectomized calves, has lost the ability to infect the natural vector Rhipicephalus (Boophilus) microplus. In this study, infection with mixed parasites from the vaccine strain and a field isolate, resulted in transmission of both genotype populations. Comparing the field isolate and transmitted combination indicated no significant difference in their virulence, while challenge of vaccinated cattle with these isolates showed the ability of the vaccine to protect against both. Limiting dilution of the transmitted combination, followed by infection of splenectomized cattle (n=34) yielded no single infections for the vaccine strain genotype, seven clonal lines of the field isolate and one mixture of vaccine strain and field isolate. Only one of two field isolate clonal lines selected for vector transmission study was transmitted. Showing that B. bovis isolates can contain both tick transmissible and non-transmissible subpopulations. The findings of this study also indicate the probability of vaccine co-infection transmission occurring in the field, which may result in new genotype populations of B. bovis. However, the impact of this recombination with field isolates is considered negligible since a genotypically diverse population of B. bovis is already present in South Africa. Copyright © 2014 Elsevier GmbH. All rights reserved.

  8. 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.

  9. Protection from persistent infection with a bovine viral diarrhea virus (BVDV) type 1b strain by a modified-live vaccine containing BVDV types 1a and 2, infectious bovine rhinotracheitis virus, parainfluenza 3 virus and bovine respiratory syncytial virus.

    Science.gov (United States)

    Xue, Wenzhi; Mattick, Debra; Smith, Linda

    2011-06-24

    Recent studies showed that BVDV-1b subgenotype is dominant in North and South American field BVDV isolates. However, nearly all commercially available BVDV-1 vaccines contain BVDV-1a strains. In order to study the efficacy of BVDV-1a vaccine against BVDV-1b infection, this study was designed to evaluate a modified-live vaccine (MLV) containing BVDV-1a and BVDV-2 strains for its efficacy in prevention of persistent infection of fetuses against BVDV-1b strain, when the heifers were vaccinated prior to breeding. Heifers were vaccinated subcutaneously with a single dose of the MLV and bred four weeks after vaccination. The pregnant heifers were challenged with a non-cytopathic BVDV-1b strain at approximately 80 days of gestation. Vaccinated heifers were protected from clinical disease and viremia caused by the BVDV-1b virus. At approximately 155 days of gestation, the fetuses were harvested and tissue samples of thymus, lungs, spleen, kidney and intestines were collected for virus isolation. BVDV was isolated from 100% of the fetuses in the non-vaccinated control group, and from only one fetus (4.3%) from the vaccinated group. Results demonstrated that the MLV containing BVDV-1a and BVDV-2 strains provided 96% protection from fetal persistent infection caused by the BVDV-1b strain. Copyright © 2011 Elsevier Ltd. All rights reserved.

  10. 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.

  11. The Efficacy of the BCG Vaccine against Newly Emerging Clinical Strains of Mycobacterium tuberculosis.

    Directory of Open Access Journals (Sweden)

    Marcela Henao-Tamayo

    Full Text Available To date, most new vaccines against Mycobacterium tuberculosis, including new recombinant versions of the current BCG vaccine, have usually been screened against the laboratory strains H37Rv or Erdman. In this study we took advantage of our recent work in characterizing an increasingly large panel of newly emerging clinical isolates [from the United States or from the Western Cape region of South Africa], to determine to what extent vaccines would protect against these [mostly high virulence] strains. We show here that both BCG Pasteur and recombinant BCG Aeras-422 [used here as a good example of the new generation BCG vaccines] protected well in both mouse and guinea pig low dose aerosol infection models against the majority of clinical isolates tested. However, Aeras-422 was not effective in a long term survival assay compared to BCG Pasteur. Protection was very strongly expressed against all of the Western Cape strains tested, reinforcing our viewpoint that any attempt at boosting BCG would be very difficult to achieve statistically. This observation is discussed in the context of the growing argument made by others that the failure of a recent vaccine trial disqualifies the further use of animal models to predict vaccine efficacy. This viewpoint is in our opinion completely erroneous, and that it is the fitness of prevalent strains in the trial site area that is the centrally important factor, an issue that is not being addressed by the field.

  12. A novel live attenuated anthrax spore vaccine based on an acapsular Bacillus anthracis Sterne strain with mutations in the htrA, lef and cya genes.

    Science.gov (United States)

    Chitlaru, Theodor; Israeli, Ma'ayan; Rotem, Shahar; Elia, Uri; Bar-Haim, Erez; Ehrlich, Sharon; Cohen, Ofer; Shafferman, Avigdor

    2017-10-20

    We recently reported the development of a novel, next-generation, live attenuated anthrax spore vaccine based on disruption of the htrA (High Temperature Requirement A) gene in the Bacillus anthracis Sterne veterinary vaccine strain. This vaccine exhibited a highly significant decrease in virulence in murine, guinea pig and rabbit animal models yet preserved the protective value of the parental Sterne strain. Here, we report the evaluation of additional mutations in the lef and cya genes, encoding for the toxin components lethal factor (LF) and edema factor (EF), to further attenuate the SterneΔhtrA strain and improve its compatibility for human use. Accordingly, we constructed seven B. anthracis Sterne-derived strains exhibiting different combinations of mutations in the htrA, cya and lef genes. The various strains were indistinguishable in growth in vitro and in their ability to synthesise the protective antigen (PA, necessary for the elicitation of protection). In the sensitive murine model, we observed a gradual increase (ΔhtrAattenuation - up to 10 8 -fold relative to the parental Sterne vaccine strain. Most importantly, all various SterneΔhtrA derivative strains did not differ in their ability to elicit protective immunity in guinea pigs. Immunisation of guinea pigs with a single dose (10 9 spores) or double doses (>10 7 spores) of the most attenuated triple mutant strain SterneΔhtrAlef MUT Δcya induced a robust immune response, providing complete protection against a subsequent respiratory lethal challenge. Partial protection was observed in animals vaccinated with a double dose of as few as 10 5 spores. Furthermore, protective immune status was maintained in all vaccinated guinea pigs and rabbits for at least 40 and 30weeks, respectively. Copyright © 2017 Elsevier Ltd. All rights reserved.

  13. Complete Protection against Pneumonic and Bubonic Plague after a Single Oral Vaccination.

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    Anne Derbise

    Full Text Available No efficient vaccine against plague is currently available. We previously showed that a genetically attenuated Yersinia pseudotuberculosis producing the Yersinia pestis F1 antigen was an efficient live oral vaccine against pneumonic plague. This candidate vaccine however failed to confer full protection against bubonic plague and did not produce F1 stably.The caf operon encoding F1 was inserted into the chromosome of a genetically attenuated Y. pseudotuberculosis, yielding the VTnF1 strain, which stably produced the F1 capsule. Given orally to mice, VTnF1 persisted two weeks in the mouse gut and induced a high humoral response targeting both F1 and other Y. pestis antigens. The strong cellular response elicited was directed mostly against targets other than F1, but also against F1. It involved cells with a Th1-Th17 effector profile, producing IFNγ, IL-17, and IL-10. A single oral dose (108 CFU of VTnF1 conferred 100% protection against pneumonic plague using a high-dose challenge (3,300 LD50 caused by the fully virulent Y. pestis CO92. Moreover, vaccination protected 100% of mice from bubonic plague caused by a challenge with 100 LD50 Y. pestis and 93% against a high-dose infection (10,000 LD50. Protection involved fast-acting mechanisms controlling Y. pestis spread out of the injection site, and the protection provided was long-lasting, with 93% and 50% of mice surviving bubonic and pneumonic plague respectively, six months after vaccination. Vaccinated mice also survived bubonic and pneumonic plague caused by a high-dose of non-encapsulated (F1- Y. pestis.VTnF1 is an easy-to-produce, genetically stable plague vaccine candidate, providing a highly efficient and long-lasting protection against both bubonic and pneumonic plague caused by wild type or un-encapsulated (F1-negative Y. pestis. To our knowledge, VTnF1 is the only plague vaccine ever reported that could provide high and durable protection against the two forms of plague after a single

  14. Serological and bacteriological responses of water buffalo (Bubalus bubalis) vaccinated with two doses of Brucella abortus strain RB51 vaccine.

    Science.gov (United States)

    Ramnanan, Anil; Diptee, Michael; Asgarali, Zinora; Campbell, Mervyn; Adesiyun, Abiodun Adewale

    2012-10-01

    Thirty-two water buffalo (Bubalus bubalis) calves aged 6–10 months were used to evaluate serological responses to Brucella abortus strain RB51 (RB51) vaccination in a dose-response study and to compare the use of two selective media for the isolation of RB51. The animals were randomly divided into three treatment groups. Groups I-III received the recommended vaccine dose (RD) twice 4 weeks apart, RD twice 18 weeks apart and saline once, respectively. Lymph nodes were excised from the three groups and subjected to bacteriological examination to determine the frequency of detection of RB51. Pre- and post-vaccination blood samples were collected and tested for B. abortus antibodies using the buffered plate agglutination test (BPAT), complement fixation test (CFT), and dot-blot assay. Sera taken at all post-inoculation weeks (PIW) were negative for field strain B. abortus using the BPAT. Antibody responses to RB51 were demonstrated in all vaccinates but not in controls by CFT and dot-blot assay from 1 PIW up to 16 weeks following booster vaccination. The agreement for both assays was 80.7% and there was a linear interdependence with a Pearson's correlation coefficient value of 0.578. The frequency of isolation of RB51 from the two selective media used was not significantly different (P > 0.05).

  15. Effect of vaccination of pigs against experimental infection with high and low virulence Mycoplasma hyopneumoniae strains.

    Science.gov (United States)

    Villarreal, I; Maes, D; Vranckx, K; Calus, D; Pasmans, F; Haesebrouck, F

    2011-02-17

    This study investigated the infection pattern and lung lesion development in pigs caused by a low and highly virulent Mycoplasma hyopneumoniae strain at 4 and 8 weeks (w) post infection (PI). It also determined the efficacy of a commercial inactivated whole-cell vaccine against infection with each one of these M. hyopneumoniae strains. Ninety piglets free of M. hyopneumoniae were selected, and 40 of them were randomly vaccinated during their first week of life. At weaning, all piglets were allocated to 10 different groups and housed in pens with absolute filters. At 4 weeks of age, pigs were inoculated intratracheally with either a highly virulent M. hyopneumoniae strain, a low virulent strain or with sterile culture medium. Half of all animals were euthanized at 4 w PI, while the remaining half was euthanized at 8 w PI. Coughing was assessed daily, and lung lesions, immunofluorescence (IF), bacteriological analysis and nested PCR were assessed after necropsy. It was demonstrated that contrary to the highly virulent strain, the low virulent strain required more than 4 weeks PI (commonly accepted as the standard infection model) to reach maximum clinical symptoms. Vaccination significantly reduced clinical symptoms, macroscopic and microscopic lung lesions in pigs infected with the highly virulent strain. This effect was more pronounced at 4 than at 8 weeks PI. Protective efficacy was also observed in pigs infected with the low virulent strain, but the effect was less pronounced than on the highly virulent strain. Copyright © 2011 Elsevier Ltd. All rights reserved.

  16. Sequence-based prediction for vaccine strain selection and identification of antigenic variability in foot-and-mouth disease virus.

    Directory of Open Access Journals (Sweden)

    Richard Reeve

    2010-12-01

    Full Text Available Identifying when past exposure to an infectious disease will protect against newly emerging strains is central to understanding the spread and the severity of epidemics, but the prediction of viral cross-protection remains an important unsolved problem. For foot-and-mouth disease virus (FMDV research in particular, improved methods for predicting this cross-protection are critical for predicting the severity of outbreaks within endemic settings where multiple serotypes and subtypes commonly co-circulate, as well as for deciding whether appropriate vaccine(s exist and how much they could mitigate the effects of any outbreak. To identify antigenic relationships and their predictors, we used linear mixed effects models to account for variation in pairwise cross-neutralization titres using only viral sequences and structural data. We identified those substitutions in surface-exposed structural proteins that are correlates of loss of cross-reactivity. These allowed prediction of both the best vaccine match for any single virus and the breadth of coverage of new vaccine candidates from their capsid sequences as effectively as or better than serology. Sub-sequences chosen by the model-building process all contained sites that are known epitopes on other serotypes. Furthermore, for the SAT1 serotype, for which epitopes have never previously been identified, we provide strong evidence--by controlling for phylogenetic structure--for the presence of three epitopes across a panel of viruses and quantify the relative significance of some individual residues in determining cross-neutralization. Identifying and quantifying the importance of sites that predict viral strain cross-reactivity not just for single viruses but across entire serotypes can help in the design of vaccines with better targeting and broader coverage. These techniques can be generalized to any infectious agents where cross-reactivity assays have been carried out. As the parameterization

  17. 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.

  18. Assessing virulence of vaccine strains of Mycobacterium avium subspecies paratuberculosis in a calf model.

    Science.gov (United States)

    Watkins, Craig; Schock, Alex; May, Linda; Denham, Susan; Sales, Jill; Welch, Louise; Sharp, J Michael; Stevenson, Karen

    2010-11-20

    The purpose of this investigation was to characterise the virulence of two Mycobacterium avium subspecies paratuberculosis (M.a. paratuberculosis) vaccine strains and compare them with a recent virulent isolate in new born calves over a time course of 8 months post-inoculation. Paratuberculosis-free new born calves were inoculated orally with either a vaccine strain (2e or 316F) or a wild type strain (F13) of M.a. paratuberculosis. Blood and faecal samples were collected throughout the experiment to analyse immune responses to infection and assess faecal shedding of M.a. paratuberculosis. Tissue samples were taken at post-mortem for histological examination and bacteriological culture. Cell-mediated immune responses were measured using a Bovigam (CSL) interferon-gamma assay. At 20 weeks post-inoculation there was a significant increase in the cell-mediated immune responses in calves infected with the wild type strain relative to the two vaccine strains. Acid fast bacteria were detected in the faeces of calves in all three groups between 4 and 8 weeks post-inoculation. Histopathology was unrewarding in all three groups. M.a. paratuberculosis was recovered only from tissues of calves inoculated with the wild type strain. Therefore, it appeared that the vaccine strains used in this study had reduced virulence. Identifying the genes responsible for pathogenesis observed in the wild type isolate and reduced or inactive in these vaccine isolates may offer a valuable resource for improving our knowledge of pathogenesis and permit the development of improved diagnostic reagents and vaccines for the control of M.a. paratuberculosis in livestock. Copyright © 2010 Elsevier B.V. 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

    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.

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

    Science.gov (United States)

    Abdallah, Abdallah M.; Hill-Cawthorne, Grant A.; Otto, Thomas D.; Coll, Francesc; Guerra-Assunção, José Afonso; Gao, Ge; Naeem, Raeece; Ansari, Hifzur; Malas, Tareq B.; Adroub, Sabir A.; 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. PMID:26487098

  1. Genomic and antigenic characterization of bovine parainfluenza-3 viruses in the United States including modified live virus vaccine (MLV) strains and field strains from cattle.

    Science.gov (United States)

    Fulton, R W; Neill, J D; Saliki, J T; Landis, C; Burge, L J; Payton, M E

    2017-05-02

    This study investigated the genetic and antigenic characterization of parainfluenza-3 virus (PI3V) of cattle. Using molecular tests including real time PCR and viral genome sequencing, PI3V strains could be separated into PI3V types, including PI3V A, PI3V B, and PI3V C. Isolates from cattle with bovine respiratory disease clinical signs and commercial vaccines in the U.S. with MLV PI3V were typed using these molecular tests. All the MLV vaccine strains tested were PI3V A. In most cases PI3V field strains from calves receiving MLV vaccines were types heterologous to the vaccine type A. Also antigenic differences were noted as PI3V C strains had lower antibody levels than PI3V A in serums from cattle receiving MLV PI3V A vaccines. This study further demonstrates there is genetic variability of U.S. PI3V strains and also antigenic variability. In addition, isolates from cattle with BRD signs and receiving MLV vaccines may have heterologous types to the vaccines, and molecular tests should be performed to differentiate field from vaccine strains. Potentially the efficacy of current PI3V A vaccines should be evaluated with other types such a PI3V B and PI3V C. Copyright © 2017 Elsevier B.V. All rights reserved.

  2. Variable Virulence and Efficacy of BCG Vaccine Strains in Mice and Correlation With Genome Polymorphisms

    Science.gov (United States)

    Zhang, Lu; Ru, Huan-wei; Chen, Fu-zeng; Jin, Chun-yan; Sun, Rui-feng; Fan, Xiao-yong; Guo, Ming; Mai, Jun-tao; Xu, Wen-xi; Lin, Qing-xia; Liu, Jun

    2016-01-01

    Bacille Calmette–Guérin (BCG), an attenuated strain of Mycobacterium bovis, is the only vaccine available for tuberculosis (TB) control. However, BCG is not an ideal vaccine and has two major limitations: BCG exhibits highly variable effectiveness against the development of TB both in pediatric and adult populations and can cause disseminated BCG disease in immunocompromised individuals. BCG comprises a number of substrains that are genetically distinct. Whether and how these genetic differences affect BCG efficacy remains largely unknown. In this study, we performed comparative analyses of the virulence and efficacy of 13 BCG strains, representing different genetic lineages, in SCID and BALB/c mice. Our results show that BCG strains of the DU2 group IV (BCG-Phipps, BCG-Frappier, BCG-Pasteur, and BCG-Tice) exhibit the highest levels of virulence, and BCG strains of the DU2 group II (BCG-Sweden, BCG-Birkhaug) are among the least virulent group. These distinct levels of virulence may be explained by strain-specific duplications and deletions of genomic DNA. There appears to be a general trend that more virulent BCG strains are also more effective in protection against Mycobacterium tuberculosis challenge. Our findings have important implications for current BCG vaccine programs and for future TB vaccine development. PMID:26643797

  3. 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.

  4. 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

  5. Amino acids analysis during lactic acid fermentation by single strain ...

    African Journals Online (AJOL)

    SAM

    2014-07-09

    Jul 9, 2014 ... Amino acids analysis during lactic acid fermentation by single strain cultures of lactobacilli and mixed culture starter made from them. KiBeom Lee1*, Ho-Jin Kim1 and Sang-Kyu Park2. 1Bio Center Technopark, 7-50 Songdo, Yeonsu-Gu, Incheon 406-840, Republic of Korea. 2Nambu University, Chumdan ...

  6. Assessment of coverage levels of single dose measles vaccine

    International Nuclear Information System (INIS)

    Tariq, P.

    2003-01-01

    Objective: To study the consequences of low coverage levels of a single dose of measles vaccine. Results: mean age observed in measles cases was 2 years and 8 months with a range from 3 months to 8 years. Maximum number of cases reported were <1 year of age (n=22,32%). Fifty percent of cases were seen among vaccinated children. Seventy-five percent (n=51) had history of contact with a measles case. Pneumonia was the commonest complication followed by acute gastroenteritis, encephalitis, febrile convulsions, oral ulcers, oral thrush, eye changes of vitamin-A deficiency and pulmonary tuberculosis (T.B.) in descending order of frequency. Fifty four cases were successfully treated for complications of measles and discharged. Nine cases left against medical advice. Five patients died all of them had encephalitis either alone (n=1) or in combination with pneumonia and acute gastroenteritis (n=4). Conclusion: There is a dire need to increase the immunization coverage to reduce the rate of vaccine failure and achieve effective control of measles.(author)

  7. Identification of the pXO1 plasmid in attenuated Bacillus anthracis vaccine strains.

    Science.gov (United States)

    Liang, Xudong; Zhang, Huijuan; Zhang, Enmin; Wei, Jianchun; Li, Wei; Wang, Bingxiang; Dong, Shulin; Zhu, Jin

    2016-07-03

    Anthrax toxins and capsule are the major virulence factors of Bacillus anthracis. They are encoded by genes located on the plasmids pXO1 and pXO2, respectively. The vaccine strain Pasteur II was produced from high temperature subcultures of B. anthracis, which resulted in virulence attenuation through the loss of the plasmid pXO1. However, it is unclear whether the high temperature culture completely abolishes the plasmid DNA or affects the replication of the plasmid pXO1. In this study, we tested 3 B. anthracis vaccine strains, including Pasteur II from France, Qiankefusiji II from Russia, and Rentian II from Japan, which were all generated from subcultures at high temperatures. Surprisingly, we detected the presence of pXO1 plasmid DNA using overlap PCR in all these vaccine strains. DNA sequencing analysis of overlap PCR products further confirmed the presence of pXO1. Moreover, the expression of the protective antigen (PA) encoded on pXO1 was determined by using SDS-PAGE and western blotting. In addition, we mimicked Pasteur's method and exposed the A16R vaccine strain, which lacks the pXO2 plasmid, to high temperature, and identified the pXO1 plasmid in the subcultures at high temperatures. This indicated that the high temperature treatment at 42.5°C was unable to eliminate pXO1 plasmid DNA from B. anthracis. Our results suggest that the attenuation of the Pasteur II vaccine strain is likely due to the impact of high temperature stress on plasmid replication, which in turn limits the copy number of pXO1. Our data provide new insights into the mechanisms of the remaining immunogenicity and toxicity of the vaccine strains.

  8. Latent Membrane Protein 1 as a molecular adjuvant for single-cycle lentiviral vaccines

    Directory of Open Access Journals (Sweden)

    Rahmberg Andrew R

    2011-05-01

    Full Text Available Abstract Background Molecular adjuvants are a promising method to enhance virus-specific immune responses and protect against HIV-1 infection. Immune activation by ligands for receptors such as CD40 can induce dendritic cell activation and maturation. Here we explore the incorporation of two CD40 mimics, Epstein Barr Virus gene LMP1 or an LMP1-CD40 chimera, into a strain of SIV that was engineered to be limited to a single cycle of infection. Results Full length LMP1 or the chimeric protein LMP1-CD40 was cloned into the nef-locus of single-cycle SIV. Human and Macaque monocyte derived macrophages and DC were infected with these viruses. Infected cells were analyzed for activation surface markers by flow cytometry. Cells were also analyzed for secretion of pro-inflammatory cytokines IL-1β, IL-6, IL-8, IL-12p70 and TNF by cytometric bead array. Conclusions Overall, single-cycle SIV expressing LMP1 and LMP1-CD40 produced a broad and potent TH1-biased immune response in human as well as rhesus macaque macrophages and DC when compared with control virus. Single-cycle SIV-LMP1 also enhanced antigen presentation by lentiviral vector vaccines, suggesting that LMP1-mediated immune activation may enhance lentiviral vector vaccines against HIV-1.

  9. Evaluation of live gumboro vaccine prepared from local variant strain for control of infectious bursal disease in Egypt

    Directory of Open Access Journals (Sweden)

    Susan S. El-Mahdy

    2013-07-01

    Full Text Available Aim: The present study was designed to evaluate live Gumboro (IBD vaccine prepared from local variant isolated strain (Egy-IBD Var 2009 Vp2 gene-, partial cds submitted in gen bank at accession no. : JN 118617 for controlling IBD problem in Egypt.Material and Methods: Local isolated variant strain was adapted on Baby Grivet Monkey kidney cell line -70(BGM-70 used for preparation of tissue culture (T.C live vaccine. T.C IBDV had a titer of 10(7.5 TCID /ml (10(4.5 TCID50 per dose after five passages in BGM-70 cell culture. Evaluation of prepared vaccine was done in vitro by measuring ELISA, and in vivo by protection % against very virulent or variant field IBD isolated strains. Result: Evaluation revealed that the prepared vaccine was safe; sterile; pure; non-immunosuppressive; and efficient. The Geometric Mean Titer (GMT of ELISA for the prepared vaccine was 8271 and more than 10000 in compared with different commercial IBD vaccines; while protection percentage gave 96-100%; 92-96% and 96-98% in groups vaccinated with commercial (intermediate; intermediate plus and classical IBD vaccines; respectively in compared to 96-100% in group vaccinated with local prepared vaccine when challenged with very virulent or variant IBD isolated strains.Conclusion: We can use live T.C. IBD vaccine prepared from local variant isolated virus strain as method for control IBD disease in Egypt.

  10. Mismatch between the 1997/1998 influenza vaccine and the major epidemic A (H3N2) virus strain as the cause of an inadequate vaccine-induced antibody response to this strain in the elderly.

    NARCIS (Netherlands)

    J.C. de Jong (Jan); W.E.Ph. Beyer (Walter); A.M. Palache (Abraham); G.F. Rimmelzwaan (Guus); A.D.M.E. Osterhaus (Albert)

    2000-01-01

    textabstractThe success of influenza vaccination depends largely on the antigenic match between the influenza vaccine strains and the virus strains actually circulating during the season. In the past, this match has proved to be satisfactory in most seasons. In the 1997/1998 season, however,

  11. 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.

  12. 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.

  13. Genetic characterisation of the rabies virus vaccine strains used for oral immunization of foxes in Poland to estimate the effectiveness of vaccination.

    Science.gov (United States)

    Orłowska, Anna; Żmudziński, Jan Franciszek

    2015-02-01

    The main reservoir of rabies virus in Poland has been the red fox. To control rabies in wildlife, oral immunization of foxes was introduced in 1993. The vaccine is effective when it confers immunity against the virus circulating in the environment. To assess the above issue, a study of the molecular characteristics of 570-bp fragments of the N and G genes of vaccine strains SAD B19 and SAD Bern against street virus strains was performed. The results confirmed the similarity of the vaccine strains and rabies virus strains circulating in the environment and also demonstrate the genetic stability of vaccine strains that have been distributed in Poland for 20 years.

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

    Directory of Open Access Journals (Sweden)

    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

  15. Tissue persistence and vaccine efficacy of tricarboxylic acid cycle and one-carbon metabolism mutant strains of Edwardsiella ictaluri.

    Science.gov (United States)

    Dahal, Neeti; Abdelhamed, Hossam; Karsi, Attila; Lawrence, Mark L

    2014-06-30

    Edwardsiella ictaluri causes enteric septicemia in fish. Recently, we reported construction of E. ictaluri mutants with single and double gene deletions in tricarboxylic acid cycle (TCA) and one-carbon (C-1) metabolism. Here, we report the tissue persistence, virulence, and vaccine efficacy of TCA cycle (EiΔsdhC, EiΔfrdA, and EiΔmdh), C-1 metabolism (EiΔgcvP and EiΔglyA), and combination mutants (EiΔfrdAΔsdhC, EiΔgcvPΔsdhC, EiΔmdhΔsdhC, and EiΔgcvPΔglyA) in channel catfish. The tissue persistence study showed that EiΔsdhC, EiΔfrdA, EiΔfrdAΔsdhC, and EiΔgcvPΔsdhC were able to invade catfish and persist until 11 days post-infection. Vaccination of catfish fingerlings with all nine mutants provided significant (P<0.05) protection against subsequent challenge with the virulent parental strain. Vaccinated catfish fingerlings had 100% survival when subsequently challenged by immersion with wild-type E. ictaluri except for EiΔgcvPΔglyA and EiΔgcvP. Mutant EiΔgcvPΔsdhC was found to be very good at protecting catfish fry, as evidenced by 10-fold higher survival compared to non-vaccinated fish. Copyright © 2014 Elsevier Ltd. All rights reserved.

  16. Genetic Vaccination against Experimental Infection with Myotropic Parasite Strains of Trypanosoma cruzi

    Directory of Open Access Journals (Sweden)

    Adriano Fernando Araújo

    2014-01-01

    Full Text Available In earlier studies, we reported that a heterologous prime-boost regimen using recombinant plasmid DNA followed by replication-defective adenovirus vector, both containing Trypanosoma cruzi genes encoding trans-sialidase (TS and amastigote surface protein (ASP 2, provided protective immunity against experimental infection with a reticulotropic strain of this human protozoan parasite. Herein, we tested the outcome of genetic vaccination of F1 (CB10XBALB/c mice challenged with myotropic parasite strains (Brazil and Colombian. Initially, we determined that the coadministration during priming of a DNA plasmid containing the murine IL-12 gene improved the immune response and was essential for protective immunity elicited by the heterologous prime-boost regimen in susceptible male mice against acute lethal infections with these parasites. The prophylactic or therapeutic vaccination of resistant female mice led to a drastic reduction in the number of inflammatory infiltrates in cardiac and skeletal muscles during the chronic phase of infection with either strain. Analysis of the electrocardiographic parameters showed that prophylactic vaccination reduced the frequencies of sinus arrhythmia and atrioventricular block. Our results confirmed that prophylactic vaccination using the TS and ASP-2 genes benefits the host against acute and chronic pathologies caused by T. cruzi and should be further evaluated for the development of a veterinary or human vaccine against Chagas disease.

  17. 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.

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

    OpenAIRE

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

    2006-01-01

    Editors' Summary Background. For thousands of years, smallpox was one of the world's most-feared diseases. This contagious disease, caused by the variola virus, historically killed about 30 percent of the people it infected. Over the centuries, it probably killed more people than all other infectious diseases combined, but it was also the first disease to be prevented by vaccination. In 1796, the English physician Edward Jenner rubbed pus from the spots of a milkmaid with cowpox into scratche...

  19. Construction of two Listeria ivanovii attenuated strains expressing Mycobacterium tuberculosis antigens for TB vaccine purposes.

    Science.gov (United States)

    Lin, Qingqing; Zhou, Mengying; Xu, Zongkai; Khanniche, Asma; Shen, Hao; Wang, Chuan

    2015-02-20

    Bacillus Calmette-Guerin (BCG) has failed in complete control of tuberculosis (TB), thus, novel tuberculosis vaccines are urgently needed. We have constructed several TB vaccine candidates, which are characterized by the use of Listeria ivanovii (LI) strain as an antigen delivery vector. Two L. ivanovii attenuated recombinant strains L. ivanovii△actAplcB-Rv0129c and L. ivanovii△actAplcB-Rv3875 were successfully screened. Results from genome PCR and sequencing showed that the Mycobacterium tuberculosis antigen gene cassette coding for Ag85C or ESAT-6 protein respectively had been integrated into LI genome downstream of mpl gene. Western blot confirmed the secretion of Ag85C or ESAT-6 protein from the recombinant LI strains. These two recombinant strains showed similar growth curves as wide type strain in vitro. In vivo, they transiently propagated in mice spleen and liver, and induced specific CD8(+) IFN-γ secretion. Therefore, in this paper, two novel LI attenuated strains expressing specific TB antigens were successfully constructed. The promising growth characteristics in mice immune system and the capability of induction of IFN-γ secretion make them of potential interest for development of TB vaccines. Copyright © 2015 Elsevier B.V. All rights reserved.

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

    Directory of Open Access Journals (Sweden)

    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.

  1. Rapid, Simple and Cost-Effective Molecular Method to Differentiate the Temperature Sensitive (ts+ MS-H Vaccine Strain and Wild-Type Mycoplasma synoviae Isolates.

    Directory of Open Access Journals (Sweden)

    Zsuzsa Kreizinger

    Full Text Available Mycoplasma synoviae infection in chickens and turkeys can cause respiratory disease, infectious synovitis and eggshell apex abnormality; thus it is an economically important pathogen. Control of M. synoviae infection comprises eradication, medication or vaccination. The differentiation of the temperature sensitive (ts+ MS-H vaccine strain from field isolates is crucial during vaccination programs. Melt-curve and agarose gel based mismatch amplification mutation assays (MAMA are provided in the present study to distinguish between the ts+ MS-H vaccine strain, its non-temperature sensitive re-isolates and wild-type M. synoviae isolates based on the single nucleotide polymorphisms at nt367 and nt629 of the obg gene. The two melt-MAMAs and the two agarose-MAMAs clearly distinguish the ts+ MS-H vaccine strain genotype from its non-temperature sensitive re-isolate genotype and wild-type M. synoviae isolate genotype, and no cross-reactions with other Mycoplasma species infecting birds occur. The sensitivity of the melt-MAMAs and agarose-MAMAs was 103 and 104 copy numbers, respectively. The assays can be performed directly on clinical samples and they can be run simultaneously at the same annealing temperature. The assays can be performed in laboratories with limited facilities, using basic real-time PCR machine or conventional thermocycler coupled with agarose gel electrophoresis. The advantages of the described assays compared with previously used methods are simplicity, sufficient sensitivity, time and cost effectiveness and specificity.

  2. Poliovirus vaccine strains detected in stool specimens of immunodeficient children in South Africa.

    Science.gov (United States)

    Pavlov, Dobromir N; Van Zyl, Walda B; Kruger, Mariane; Blignaut, Liezl; Grabow, Willie O K; Ehlers, Marthie M

    2006-01-01

    After exposure to the oral poliovirus vaccine (OPV), immunocompetent persons excrete poliovirus (PV) vaccine strains for a limited period. In contrast, immunodeficient individuals remain sometimes chronically infected, and in some cases, PV excretion times as long as 10 years have been reported. During prolonged replication in the human intestine, the PV vaccine strain almost invariably reverts its attenuated character and acquires neurovirulent properties (vaccine-derived PVs, or VDPVs), which resemble wild-type PV strains. The aim of this study was to determine the occurrence of OPV strains in stools of immunodeficient children from a selected area in South Africa, as a first step toward future research on the prevalence and potential health impact of VDPVs. In a period of 1 year, a total of 164 stool samples of HIV-positive children aged 4 months to 8 years were studied for the excretion of OPV strains. In addition, 23 stool samples from healthy immunocompetent children were analyzed after receiving their OPV immunization. By applying a reverse transcription-polymerase chain reaction in combination with a nested PCR, a total of 54 enteroviruses (EVs) were detected in the stool specimens of the immunodeficient children. Using restriction enzyme analysis, 13 PVs were distinguished from 41 nonpolio EVs (NPEVs). A Sabin-specific RT-triplex PCR confirmed the presence of 7 Sabin PV type 1, 4 Sabin PV type 3, and 2 Sabin PV type 2 isolates. The majority of the NPEV group was made up of 7 coxsackievirus B3 (CBV3), 6 echovirus 11 (ECV11), 5 ECV9, and 3 coxsackievirus A6 (CAV6) isolates. According to the results, two of the immunodeficient patients (P023 and P140) who had received their last OPV immunization more than 15 months before (vaccinated at 14 weeks of age) tested positive for Sabin PVs types 3 and 1, respectively. A 5-year-old immunodeficient patient (P052) who had received her last OPV immunization more than 42 months before (vaccinated at 18 months of age

  3. Vaccination with Attenuated Neisseria meningitidis Strains Protects against Challenge with Live Meningococci

    OpenAIRE

    Li, Yanwen; Sun, Yao-hui; Ison, Cathy; Levine, Myron M.; Tang, Christoph M.

    2004-01-01

    Meningococcal disease is a life-threatening infection caused by Neisseria meningitidis. Currently, there are no vaccines to prevent infection with serogroup B N. meningitidis strains, the leading cause of meningococcal meningitis in Europe and North America. Here we describe the construction and characterization of two attenuated serogroup B N. meningitidis strains, YH102 (MC58Δsia ΔrfaF) and YH103 (MC58Δsia ΔmetH). Both strains are markedly attenuated in their capacity to cause bacteremia in...

  4. The efficacy of CP7_E2alf: an animal study involving piglets from C–strain vaccinated sows

    DEFF Research Database (Denmark)

    Rangelova, Desislava Yordanova; Nielsen, Jens; Strandbygaard, Bertel

    previously vaccinated with C-strain interferes with the efficacy of CP7_E2alf vaccination. To study the interaction with maternal antibodies, the efficacy of CP7_E2alf in piglets from C-strain vaccinated sows was examined. At 5 or at 8 weeks of age, piglets were vaccinated with CP7_E2alf. The vaccinated....... Interestingly, the antibodies in the mock-vaccinated control piglets partly neutralized the challenge virus. In earlier studies CSFV Koslov has resulted in 100% mortality in naïve piglets, in this study mortality was reduced to 30% in the piglets infected at 7 weeks of age and to 50% in the piglets infected...... at 10 weeks of age. In the present study optimal time point for vaccination of piglets with passive immunity was found to be 5 weeks of age....

  5. Which influenza vaccine formulation should be used in Kenya? A comparison of influenza isolates from Kenya to vaccine strains, 2007-2013

    NARCIS (Netherlands)

    Waiboci, L.W.; Mott, J.A.; Kikwai, G.; Arunga, G.; Xu, X.; Mayieka, L.; Emukule, G.O.; Muthoka, P.; Njenga, M.K.; Fields, B.S.; Katz, M.A.

    2016-01-01

    INTRODUCTION: Every year the World Health Organization (WHO) recommends which influenza virus strains should be included in a northern hemisphere (NH) and a southern hemisphere (SH) influenza vaccine. To determine the best vaccine formulation for Kenya, we compared influenza viruses collected in

  6. COMPARATIVE IMMUNO PATHOLOGICAL AND IMMUNOSUPPRESSIVE EEFECTS OF THREE DIFFERENT GUMBORO VACCINE STRAINS AGAINST NEWCASTLE DISEASE VACCINA TION IN BROILERS

    Directory of Open Access Journals (Sweden)

    R. M. Ayyub, A. Aslam, S. A. Khan and M. A. Munir1

    2003-12-01

    Full Text Available This project was carried out to study the comparative immunosuppressive effects of three different Gumboro live vaccine strains on Newcastle disease (NO vaccination. A total of 100 chicks were divided into four equal groups (A, B, C and O. Birds of all the groups were vaccinated against ND on 5th and 21st day of age. Specific Gumboro vaccine strain was given to specific group at 14th and 28th day of age. Group A, Band C were vaccinated with 228-E, D- 78 and Bursine-2, respectively, while group D was kept as control. Immune organs including bursa, thymus and spleen were examined for their gross and, histopathological changes, before and after Infectious Bursal disease (IBO vaccination. For this purpose, these organs were collected at 13th, 17th and 31st days of age. At 13th day (before 1BD vaccination no gross and histopathological lesions were observed in any bird of any group. At 17th and 31st day, severe lesions were noted in group A, moderate lesions in group B, mild lesions in group C and no lesions were observed in immune organs of group D. Haemagglutination inhibition (HI test showed that 228-E vaccine strain, (group A was highly immunosuppressive, D- 78 vaccine strain (group B was less immunosuppressive while Bursine-2 vaccine strain (group C was least immunosuppressive. No humoral immunosuppression was observed in unvaccinated control group D. This study suggests the use of Bursine-2 strain of IBD vaccine in a flock having risk of ND infection, as it has least immunosuppressive effect against ND vaccination.

  7. Efficacy of the oral rabies virus vaccine strain SPBN GASGAS in foxes and raccoon dogs.

    Science.gov (United States)

    Freuling, Conrad M; Eggerbauer, Elisa; Finke, Stefan; Kaiser, Christiane; Kaiser, Christian; Kretzschmar, Antje; Nolden, Tobias; Ortmann, Steffen; Schröder, Charlotte; Teifke, Jens P; Schuster, Peter; Vos, Ad; Mettenleiter, Thomas C; Müller, Thomas

    2017-10-14

    To test the immunogenicity and efficacy of a new oral rabies virus vaccine strain SPBN GASGAS in wildlife target species, one group of foxes and two groups of raccoon dogs were offered a bait containing 1.7 ml of the vaccine (10 6.6  FFU/ml; 10 6.8  FFU/dose) and subsequently challenged approximately 180 days later with a fox rabies virus isolate. One group of raccoon dogs (n=30) received the same challenge dose (10 0.7  MICLD 50 /ml) as the red foxes (n=29). The other group with raccoon dogs (n=28) together with 8 animals that received the vaccine dose by direct instillation into the oral cavity (DIOC) were infected with a 40-fold higher dose of the challenge virus (10 2.3  MICLD 50 /ml). All but one of the 29 vaccinated foxes survived the challenge infection; meanwhile all 12 control foxes succumbed to rabies. Twenty-eight of 30 vaccinated raccoon dogs challenged with the same dose survived the infection, however only six of 12 control animals succumbed. When the higher challenge dose was administered, all 12 control animals died from rabies and all 36 vaccinated animals (28 baited plus 8 DIOC) survived. Blood samples were collected at different time points post vaccination and examined by both RFFIT and ELISA. The kinetics of the measured immune response was similar for both species, although in RFFIT slightly higher values were observed in foxes than in raccoon dogs. However, the immune response as measured in ELISA was identical for both species. The oral rabies virus vaccine SPBN GASGAS meets the efficacy requirements for live rabies virus vaccines as laid down by the European Pharmacopoeia. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.

  8. Vaccination with a BCG strain overexpressing Ag85B protects cattle against Mycobacterium bovis challenge.

    Directory of Open Access Journals (Sweden)

    Caroline Rizzi

    Full Text Available Mycobacterium bovis is the causative agent of tuberculosis in cattle but also infects other animals, including humans. Previous studies in cattle have demonstrated that the protection induced by BCG is not complete. In order to improve the protection efficacy of BCG, in this study we overexpressed Ag85B in a BCG Pasteur strain, by using an expression system based on the use of an auxotrophic strain for the leucine amino acid, and complementation with leuD. We found that vaccination of cattle with BCG overexpressing Ag85B induced higher production of IL-17 and IL-4 mRNA upon purified protein derivative (PPDB stimulation of peripheral blood mononuclear cells (PBMCs than vaccination with BCG. Moreover, the IL-17 mRNA expression after vaccination negatively correlated with disease severity resulting from a subsequent challenge with M. bovis, suggesting that this cytokine is a potential biomarker of cattle protection against bovine tuberculosis. Importantly, vaccination with the recombinant BCG vaccine protected cattle better than the wild-type BCG Pasteur.

  9. Outer Membrane Proteins of Brucella abortus Vaccinal and Field Strains and their Immune Response in Buffaloes

    Directory of Open Access Journals (Sweden)

    Rukhshanda Munir*, M. Afzal1, M. Hussain2, S. M. S. Naqvi3 and A. Khanum3

    2010-04-01

    Full Text Available Outer membrane proteins (OMPs of three strains of B. abortus i.e. S19, RB51 and a local field isolate of biotype 1 were isolated through disrupting cells to generate membranes by centrifugation and sodium lauryl sarcosinate solubilisation of inner membrane proteins. Distinct OMP profiles of each strain were seen on SDS-PAGE. SDS-PAGE analysis of S19 and field isolate revealed eight protein bands in each strain. The OMPs of S19 had molecular masses 89.0, 73.0, 53.7, 49.0, 38.0, 27.0, 22.3, and 17.7 kDa, while field isolate had OMPs of 151.3, 89.0, 75.8, 67.6, 37.0, 27.0, 24.0 and 19.0 kDa. B. abortus RB51 yielded 11 OMP bands ranging from 12.5 to 107.1 kDa, with 34.2, 15.8 and 12.5 kDa as additional OMPs. Western immunoblot analysis using antisera raised against all three strains in buffaloes indicated an almost similar pattern of immuno-reactive OMPs in S19 and field strain. Two OMPs of molecular weight 37-38 and 19 kDa were immuno-reactive in all strains in buffaloes. There is possibility of use of these OMPs in a recombinant vaccine for B. abortus. A distinct protein of molecular weight of 151.3 kDa was identified in field strain but not in both vaccine strains of B. abortus. Use of this OMP in a diagnostic assay may differentiate between vaccinated and infected animals.

  10. Antigenic characterization of Moraxella bovis, Moraxella bovoculi and Moraxella ovis strains with potential use in vaccines.

    Science.gov (United States)

    Kowalski, Ananda Paula; Maboni, Grazieli; Gressler, Letícia Trevisan; Espíndola, Julia Pires; Balzan, Cláudia; Tasca, Caiane; Guizzo, João Antônio; Conceição, Fabricio Rochedo; Frandoloso, Rafael; de Vargas, Agueda Castagna

    2017-10-01

    Moraxella bovis is historically known as the primary agent of infectious bovine keratoconjunctivitis (IBK). However, Moraxella bovoculi and Moraxella ovis are also reported to be involved in the pathogenesis of IBK, therefore, these three species should be included in the development of a new vaccine with a broad-spectrum protection against the disease natural challenge. In this study we investigated the antigenic properties of clinical isolates and reference strains of M. bovis, M. bovoculi and M. ovis using a novel in vitro approach for vaccine evaluation based on two techniques, flow cytometry and western blotting (WB). Here, we demonstrated that rabbit antisera produced against reference M. bovis strain and commercial bacterin showed low number of IgG with capacity to recognize a panel of heterologous strains composed by M. bovoculi and M. ovis. On the other hand, the antisera generated against two clinical isolates of M. ovis (Mov2 and Mov3) presented high cross-reactivity levels against all M. ovis and M. bovis strains evaluated. Similarly, the antisera against Mbv3 (clinical isolate of M. bovoculi) had high levels of IgG associated on the surface of all M. bovoculi strains and most of the M. ovis strains analyzed. The WB analysis demonstrated that Moraxella spp. has multiple immunogenic antigens and most of them are shared between the three species. Based on the cross-reactivity analysis and considering the relative number of IgGs associated on the bacterial surface, we suggest that a multivalent vaccine including Mbv3, Mov2 and Mov3 strains may provide a strong and broad protection against all strains involved in IBK outbreaks. Copyright © 2017 Elsevier B.V. All rights reserved.

  11. 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.

  12. Overexpression of Protective Antigen as a Novel Approach To Enhance Vaccine Efficacy of Brucella abortus Strain RB51

    OpenAIRE

    Vemulapalli, Ramesh; He, Yongqun; Cravero, Silvio; Sriranganathan, Nammalwar; Boyle, Stephen M.; Schurig, Gerhardt G.

    2000-01-01

    Brucella abortus strain RB51 is an attenuated rough strain that is currently being used as the official live vaccine for bovine brucellosis in the United States and several other countries. We reasoned that overexpression of a protective antigen(s) of B. abortus in strain RB51 should enhance its vaccine efficacy. To test this hypothesis, we overexpressed Cu/Zn superoxide dismutase (SOD) protein of B. abortus in strain RB51. This was accomplished by transforming strain RB51 with a broad-host-r...

  13. Overexpression of Protective Antigen as a Novel Approach To Enhance Vaccine Efficacy of Brucella abortus Strain RB51

    Science.gov (United States)

    Vemulapalli, Ramesh; He, Yongqun; Cravero, Silvio; Sriranganathan, Nammalwar; Boyle, Stephen M.; Schurig, Gerhardt G.

    2000-01-01

    Brucella abortus strain RB51 is an attenuated rough strain that is currently being used as the official live vaccine for bovine brucellosis in the United States and several other countries. We reasoned that overexpression of a protective antigen(s) of B. abortus in strain RB51 should enhance its vaccine efficacy. To test this hypothesis, we overexpressed Cu/Zn superoxide dismutase (SOD) protein of B. abortus in strain RB51. This was accomplished by transforming strain RB51 with a broad-host-range plasmid, pBBR1MCS, containing the sodC gene along with its promoter. Strain RB51 overexpressing SOD (RB51SOD) was tested in BALB/c mice for its ability to protect against challenge infection with virulent strain 2308. Mice vaccinated with RB51SOD, but not RB51, developed antibodies and cell-mediated immune responses to Cu/Zn SOD. Strain RB51SOD vaccinated mice developed significantly (P RB51 alone. The presence of the plasmid alone in strain RB51 did not alter its vaccine efficacy. Also, overexpression of SOD did not alter the attenuation characteristic of strain RB51. PMID:10816475

  14. Evaluation of Recombinant Attenuated Salmonella Vaccine Strains for Broad Protection against Extraintestinal Pathogenic Escherichia coli

    Directory of Open Access Journals (Sweden)

    Jacob T. Maddux

    2017-10-01

    Full Text Available Antibiotic-resistant bacterial infections are difficult to treat, producing a burden on healthcare and the economy. Extraintestinal pathogenic Escherichia coli (ExPEC strains frequently carry antibiotic resistance genes, cause infections outside of the intestine, and are causative agents of hospital-acquired infections. Developing a prevention strategy against this pathogen is challenging due to its antibiotic resistance and antigenic diversity. E. coli common pilus (ECP is frequently found in ExPEC strains and may serve as a common antigen to induce protection against several ExPEC serotypes. In addition, live recombinant attenuated Salmonella vaccine (RASV strains have been used to prevent Salmonella infection and can also be modified to deliver foreign antigens. Thus, the objective of this study was to design a RASV to produce ECP on its surface and assess its ability to provide protection against ExPEC infections. To constitutively display ECP in a RASV strain, we genetically engineered a vector (pYA4428 containing aspartate-β-semialdehyde dehydrogenase and E. coli ecp genes and introduced it into RASV χ9558. RASV χ9558 containing an empty vector (pYA3337 was used as a control to assess protection conferred by the RASV strain without ECP. We assessed vaccine efficacy in in vitro bacterial inhibition assays and mouse models of ExPEC-associated human infections. We found that RASV χ9558(pYA4428 synthesized the major pilin (EcpA and tip pilus adhesin (EcpD on the bacterial surface. Mice orally vaccinated with RASV χ9558(pYA3337 without ECP or χ9558(pYA4428 with ECP, produced anti-Salmonella LPS and anti-E. coli EcpA and EcpD IgG and IgA antibodies. RASV strains showed protective potential against some E. coli and Salmonella strains as assessed using in vitro assays. In mouse sepsis and urinary tract infection challenge models, both vaccines had significant protection in some internal organs. Overall, this work showed that RASVs can elicit

  15. 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

  16. 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...... as a live vaccine in Poland, and the Hungarian isolates were related to the Bartha K-61 vaccine strain widely used in Hungary. Pigs experimentally infected with derivatives of BUK-TK-900 or BUK-TK-900 itself were found to develop gI-antibodies, while pigs infected with derivatives of Bartha K-61 showed a g...

  17. 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.

  18. 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.

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

    Science.gov (United States)

    Vranckx, Katleen; Maes, Dominiek; Marchioro, Silvana B; Villarreal, Iris; Chiers, Koen; Pasmans, Frank; Haesebrouck, Freddy

    2012-03-12

    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. 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. 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.

  20. Chinese border disease virus strain JSLS12-01 infects piglets and down-regulates the antibody responses of classical swine fever virus C strain vaccination.

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    Mao, Li; Li, Wenliang; Liu, Xia; Hao, Fei; Yang, Leilei; Deng, Jiawu; Zhang, Wenwen; Wei, Jianzhong; Jiang, Jieyuan

    2015-07-31

    During 2012 and 2013, several border disease virus (BDV) strains were identified from Chinese goat and sheep herds. At the same time, pigs from the same areas were found to be seropositive to BDV by ELISA, without showing clinical signs (unpublished data). To examine the susceptibility of pigs to the Chinese BDV strains, BDV isolate JSLS12-01, isolated from naturally infected sheep, was used to infect pigs. Antibody responses, viremia, clinical signs and pathological changes of the infected animals were examined. It confirmed that the current BDV strain could infect the domestic pigs, the animals showed viremia during 4 to 14 days post infection (dpi) and sero-conversion from 14dpi; no clinical and pathological changes were observed. In addition, CSFV maternal antibody did not influence BDV infection. Subsequently, pigs were infected with the BDV isolate and vaccinated with Hog cholera lapinized virus (HCLV) 21 days later to determine the effect of BDV infection on antibody induction of CSFV vaccination. The specific CSFV antibody and neutralizing antibody titers of the BDV infected group remained negative after the primary vaccination. Even after the boost vaccination, they were still significantly lower than those of the uninfected groups (p<0.05). These results indicated that BDV infection could down-regulate the antibody responses of CSFV C-strain vaccination. It should be paid attention that BDV prevalence in pig herds and in live vaccines might hamper the vaccination of CSF. Copyright © 2015 Elsevier Ltd. All rights reserved.

  1. 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

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

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    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

  3. Predicted strain coverage of a meningococcal multicomponent vaccine (4CMenB) in Portugal.

    Science.gov (United States)

    Simões, Maria João; Bettencourt, Célia; De Paola, Rosita; Giuliani, Maria; Pizza, Mariagrazia; Moschioni, Monica; Machado, Jorge

    2017-01-01

    Although the incidence of meningococcal disease has been declining over the past decade in Portugal MenB meningococci is still an important cause of meningitis and sepsis. The aim of this study was to estimate the strain coverage of the 4CMenB vaccine in Portugal in order to support health policies for prevention and control of meningococcal disease. Since 2002 the clinical and laboratory notification of meningococcal disease is mandatory in Portugal. National database includes since then all confirmed cases notified to the reference laboratory or to the Directorate of Health. Strains included in this study were all the invasive MenB isolated from the 1st July 2011 to the 30th June 2015, sent to the reference laboratory. To predict the vaccine strain coverage of the 4CMenB the expression and cross-reactivity of the surface antigens fHbp, NadA, NHBA were assessed by the Meningococcal Antigen Typing System (MATS) whereas PorA typing was performed by sequencing. The presence of at least one antigen with a Relative Potency (RP) greater than its MATS-positive bactericidal threshold RP value or the presence of PorA VR2 = 4 was considered to be predictive for a strain to be covered by the 4CMenB vaccine. The estimated 4CMenB strain coverage in Portugal was 67.9%. The percentage of strain coverage in each of the four epidemiological years ranged from 63.9% to 73.7%. Strains covered by one antigen represent 32.1% of the total of isolates, 29.2% of strains were covered by two antigens and 6.6% by three antigens. No strain had all the four antigens. Antigens that most contributed for coverage were NHBA and fHbp. Data from Portugal is in accordance with the MATS predicted strain coverage in five European countries (England and Wales, France, Germany, Italy and Norway) that pointed to 78% coverage for strains collected in the epidemiological year 2007-2008.

  4. Genetic and subunit vaccines based on the stem domain of the equine influenza hemagglutinin provide homosubtypic protection against heterologous strains.

    Science.gov (United States)

    Ibañez, Lorena Itatí; Caldevilla, Cecilia Andrea; Paredes Rojas, Yesica; Mattion, Nora

    2018-03-14

    H3N8 influenza virus strains have been associated with infectious disease in equine populations throughout the world. Although current vaccines for equine influenza stimulate a protective humoral immune response against the surface glycoproteins, disease in vaccinated horses has been frequently reported, probably due to poor induction of cross-reactive antibodies against non-matching strains. This work describes the performance of a recombinant protein vaccine expressed in prokaryotic cells (ΔHAp) and of a genetic vaccine (ΔHAe), both based on the conserved stem region of influenza hemagglutinin (HA) derived from A/equine/Argentina/1/93 (H3N8) virus. Sera from mice inoculated with these immunogens in different combinations and regimes presented reactivity in vitro against highly divergent influenza virus strains belonging to phylogenetic groups 1 and 2 (H1 and H3 subtypes, respectively), and conferred robust protection against a lethal challenge with both the homologous equine strain (100%) and the homosubtypic human strain A/Victoria/3/75 (H3N2) (70-100%). Animals vaccinated with the same antigens but challenged with the human strain A/PR/8/34 (H1N1), belonging to the phylogenetic group 1, were not protected (0-33%). Combination of protein and DNA immunogens showed higher reactivity to non-homologous strains than protein alone, although all vaccines were permissive for lung infection. Copyright © 2018 Elsevier Ltd. All rights reserved.

  5. Safety and immunogenicity of a glycoprotein E gene-deleted bovine herpesvirus 1 strain as a candidate vaccine strain

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    Marcelo Weiss

    Full Text Available ABSTRACT: A glycoprotein E-deleted Brazilian bovine herpesvirus 1 (BoHV-1gEΔ was tested regarding to safety and immunogenicity. Intramuscular inoculation of young calves with a high virus dose did not result in clinical signs or virus shedding during acute infection or after dexamethasone administration. Calves vaccinated once IM (group I or subcutaneously (group II with live BoHV-1gEΔ or twice with inactivated virus plus aluminum hydroxide (group IV or Montanide™ (group V developed VN titers of 2 to 8 (GMT:2; 2 to 4 (GMT:1.65; 2 to 16 (GMT:2.45 and 2 to 128 (GMT:3.9, respectively. All BoHV-1gEΔ vaccinated calves remained negative in an anti-gE ELISA. Lastly, six young calves vaccinated with live BoHV-1gEΔ and subsequently challenged with a virulent BoHV-1 strain shed less virus and developed only mild and transient nasal signs comparing to unvaccinated calves. Thus, the recombinant BoHV-1gEΔ is safe and immunogenic for calves and allows for serological differentiation by a gE-ELISA test.

  6. 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.

  7. A Matched Influenza Vaccine Strain Was Effective in Reducing the Risk of Acute Myocardial Infarction in Elderly Persons

    OpenAIRE

    Hsu, Shu-Yun; Chen, Fong-Lin; Liaw, Yung-Po; Huang, Jing-Yang; Nfor, Oswald Ndi; Chao, Day-Yu

    2016-01-01

    Abstract The aim of this study was to explore whether matched or mismatched strains of influenza vaccines (IVs) are beneficial at reducing the risk of acute myocardial infarction (AMI) in elderly persons. Data were obtained from the Longitudinal Health Database 2005 (LHID 2005) which is maintained by the National Health Insurance Research Institute in Taiwan. The analytical data included individuals who were vaccinated with mismatched vaccines during the October 2007 to December 2007 season a...

  8. Modeling the effects of prior infection on vaccine efficacy

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    Smith, D.J.; Forrest, S.; Ackley, D.H. [Univ. of New Mexico, Albuquerque, NM (United States). Dept. of Computer Science; Perelson, A.S. [Los Alamos National Lab., NM (United States)

    1997-11-01

    We performed computer simulations to study the effects of prior infection on vaccine efficacy. We injected three antigens sequentially. The first antigen, designated the prior, represented a prior infection or vaccination. The second antigen, the vaccine, represented a single component of the trivalent influenza vaccine. The third antigen, the epidemic, represented challenge by an epidemic strain. For a fixed vaccine to epidemic strain cross-reactivities to the vaccine and to the epidemic strains. We found that, for many cross-reactivities, vaccination, when it had been preceded by a prior infection, provided more protection than vaccination alone. However, at some cross-reactivities, the prior infection reduced protection by clearing the vaccine before it had the chance to produce protective memory. The cross-reactivities between the prior, vaccine and epidemic strains played a major role in determining vaccine efficacy. This work has applications to understanding vaccination against viruses such as influenza that are continually mutating.

  9. [Antigen differences of genetic variants Abent+ and Abent- poliovirus vaccine strain of III type].

    Science.gov (United States)

    Shyrobokov, V P; Kostenko, I H; Nikolaienko, I V

    2003-01-01

    Hybridomes--producers of monoclonal antibodies (MAB) were obtained able to differentiate the variants Abent+ and Abent- poliovirus vaccine strain in the virus neutralizing reaction. Using the obtained panel the changes of the epitope structure of capsid proteins of poliovirus variants (dissociants) were found which appeared during reproduction in cell culture. It proves the fact that there exist essential antigenic differences of superficial virion's proteins, which appear during the process of dissociation.

  10. 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.

  11. Analysis of Spleen-Induced Fimbria Production in Recombinant Attenuated Salmonella enterica Serovar Typhimurium Vaccine Strains

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    Paweł Łaniewski

    2017-08-01

    Full Text Available Salmonella enterica serovar Typhimurium genome encodes 13 fimbrial operons. Most of the fimbriae encoded by these operons are not produced under laboratory conditions but are likely to be synthesized in vivo. We used an in vivo expression technology (IVET strategy to identify four fimbrial operons, agf, saf, sti, and stc that are expressed in the spleen. When any three of these operons were deleted, the strain retained wild-type virulence. However, when all four operons were deleted, the resulting strain was completely attenuated, indicating that these four fimbriae play functionally redundant roles critical for virulence. In mice, oral doses of as low as 1 × 105 CFU of the strain with four fimbrial operons deleted provided 100% protection against challenge with 1 × 109 CFU of wild-type S. Typhimurium. We also examined the possible effect of these fimbriae on the ability of a Salmonella vaccine strain to deliver a guest antigen. We modified one of our established attenuated vaccine strains, χ9088, to delete three fimbrial operons while the fourth operon was constitutively expressed. Each derivative was modified to express the Streptococcus pneumoniae antigen PspA. Strains that constitutively expressed saf or stc elicited a strong Th1 response with significantly greater levels of anti-PspA serum IgG and greater protective efficacy than strains carrying saf or stc deletions. The isogenic strain in which all four operons were deleted generated the lowest anti-PspA levels and did not protect against challenge with virulent S. pneumoniae. Our results indicate that these fimbriae play important roles, as yet not understood, in Salmonella virulence and immunogenicity.

  12. 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.

  13. A single vaccination with an inactivated bovine respiratory syncytial virus vaccine primes the cellular immune response in calves with maternal antibody

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    Makoschey Birgit

    2010-01-01

    Full Text Available Abstract Background The efficacy of a single dose of an inactivated bovine respiratory syncytial virus (BRSV - Parainfluenaza type 3 (PI3 - Mannheimia haemolytica (Mh combination vaccine, in calves positive for maternal antibodies, was established in a BRSV infection study. Results As expected the single vaccination did not have any effect on the decline of BRSV-specific neutralising or ELISA antibody. The cellular immune system was however primed by the vaccination. In the vaccinated group virus excretion with nasal discharge was reduced, less virus could be re-isolated from lung tissues and the lungs were less affected. Conclusions These results indicate that a single vaccination with an inactivated BRSV vaccine was able to break through the maternal immunity and induce partial protection in very young calves. It can be speculated that the level and duration of protection will improve after the second dose of vaccine is administered. A two-dose basic vaccination schedule is recommended under field conditions.

  14. Characterization of cross protection of Swine-Origin Influenza Virus (S-OIV) H1N1 and reassortant H5N1 influenza vaccine in BALB/c mice given a single-dose vaccination.

    Science.gov (United States)

    Lin, Hui-Tsu; Chuang, Chuan-Chang; Wu, Hsieh-Ling; Chu, Der-Ming; Wang, Yeau-Ching

    2013-03-21

    Influenza virus has antigen drift and antigen shift effect, vaccination with some influenza vaccine might not induce sufficient immunity for host to the threat of other influenza virus strains. S-OIV H1N1 and H5N1 influenza vaccines in single-dose immunization were evaluated in mice for cross protection to the challenge of A/California/7/2009 H1N1 or NIBRG-14 H5N1 virus. Both H1N1 and H5N1 induced significant homologous IgG, HAI, and microneutralization antibody responses in the mice, while only vaccines plus adjuvant produced significant heterogeneous IgG and HAI antibody responses. Both alum and MPLA adjuvants significantly reduced the S-OIV H1N1 vaccine dose required to elicit protective HAI antibody titers from 0.05 μg to 0.001 μg. Vaccines alone did not protect mice from challenge with heterogeneous influenza virus, while H5N1 vaccine plus alum and MPLA adjuvants did. Mouse body weight loss was also less significant in the presence of adjuvant than in the vaccine without adjuvant. Furthermore, both H1N1 and H5N1 lung viral titers of immunized mice were significantly reduced post challenge with homologous viruses. Only in the presence of MPLA adjuvant could the H5N1 vaccine significantly reduce mouse lung viral titers post H1N1 virus challenge, and not vice versa. MPLA adjuvant induced cross protection with a single dose vaccination to the challenge of heterogeneous influenza virus in mice. Lung viral titer seemed to be a better indicator compared to IgG, neutralization antibody, and HAI titer to predict survival of mice infected with influenza virus.

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

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    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.

  16. Immune responses of elk to initial and booster vaccinations with Brucella abortus strain RB51 or 19.

    Science.gov (United States)

    Olsen, S C; Fach, S J; Palmer, M V; Sacco, R E; Stoffregen, W C; Waters, W R

    2006-10-01

    Previous studies have suggested that currently available brucellosis vaccines induce poor or no protection in elk (Cervus elaphus nelsoni). In this study, we characterized the immunologic responses of elk after initial or booster vaccination with Brucella abortus strains RB51 (SRB51) and 19 (S19). Elk were vaccinated with saline or 10(10) CFU of SRB51 or S19 (n=seven animals/treatment) and booster vaccinated with a similar dosage of the autologous vaccine at 65 weeks. Compared to nonvaccinates, elk vaccinated with SRB51 or S19 had greater (P0.05) from the responses of nonvaccinated elk. Gamma interferon production in response to autologous or nonautologous Brucella antigens did not differ (P>0.05) between controls and vaccinates after booster vaccination. Flow cytometric techniques suggested that proliferation occurred more frequently in immunoglobulin M-positive cells, with differences between vaccination and control treatments in CD4+ and CD8+ subset proliferation detected only at 22 weeks after initial vaccination. After booster vaccination, one technique ([3H]thymidine incorporation) suggested that proliferative responses to SRB51 antigen, but not S19 antigen, were greater (PBrucella antigens in S19 or SRB51 vaccinates after booster vaccination. Although some cellular immune responses were detected after initial or booster vaccination of elk with SRB51 or S19, our data suggest that responses tend to be transient and much less robust than previously reported in SRB51-vaccinated cattle (Bos taurus) or bison (Bison bison). These data may explain why the vaccination of elk with S19 and SRB51 induces poor protection against brucellosis.

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

    Science.gov (United States)

    Laurens, Matthew B; Kouriba, Bourema; Bergmann-Leitner, Elke; Angov, Evelina; Coulibaly, Drissa; Diarra, Issa; Daou, Modibo; Niangaly, Amadou; Blackwelder, William C; Wu, Yukun; Cohen, Joe; Ballou, W Ripley; Vekemans, Johan; Lanar, David E; Dutta, Sheetij; Diggs, Carter; Soisson, Lorraine; Heppner, D Gray; Doumbo, Ogobara K; Plowe, Christopher V; Thera, Mahamadou A

    2017-01-01

    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%, pvaccine group was 7.4 times the mean increase in the control group (pvaccination (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.gov, registry number NCT00460525.

  18. Brucella abortus vaccine strain RB51 produces low levels of M-like O-antigen.

    Science.gov (United States)

    Cloeckaert, Axel; Zygmunt, Michel S; Guilloteau, Laurence A

    2002-03-15

    Brucella abortus RB51 is a rough (R) stable vaccine strain used in cattle and is believed to be devoid of O-side chain. We analyzed by use of a panel of monoclonal antibodies (MAbs) directed against seven previously defined O-polysaccharide (O-PS) epitopes the O-chain expression in strain RB51. Two MAbs specific for the C/Y (A=M) and C (M>A) epitopes showed low bindings in ELISA to strain RB51. O-chain expression was further confirmed by Western blot after SDS-PAGE of strain RB51. In particular, the MAb of C (M>A) specificity, showing preferential binding to M-dominant smooth (S) Brucella strains, revealed in strain RB51 a typical smooth-lipopolysaccharide (S-LPS) pattern which resembled that of M-dominant S-LPS. Thus, the results clearly show that strain RB51 produces low levels of M-like O-antigen.

  19. Low 2012-13 influenza vaccine effectiveness associated with mutation in the egg-adapted H3N2 vaccine strain not antigenic drift in circulating viruses.

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    Danuta M Skowronski

    Full Text Available Influenza vaccine effectiveness (VE is generally interpreted in the context of vaccine match/mismatch to circulating strains with evolutionary drift in the latter invoked to explain reduced protection. During the 2012-13 season, however, detailed genotypic and phenotypic characterization shows that low VE was instead related to mutations in the egg-adapted H3N2 vaccine strain rather than antigenic drift in circulating viruses.Component-specific VE against medically-attended, PCR-confirmed influenza was estimated in Canada by test-negative case-control design. Influenza A viruses were characterized genotypically by amino acid (AA sequencing of established haemagglutinin (HA antigenic sites and phenotypically through haemagglutination inhibition (HI assay. H3N2 viruses were characterized in relation to the WHO-recommended, cell-passaged vaccine prototype (A/Victoria/361/2011 as well as the egg-adapted strain as per actually used in vaccine production. Among the total of 1501 participants, influenza virus was detected in 652 (43%. Nearly two-thirds of viruses typed/subtyped were A(H3N2 (394/626; 63%; the remainder were A(H1N1pdm09 (79/626; 13%, B/Yamagata (98/626; 16% or B/Victoria (54/626; 9%. Suboptimal VE of 50% (95%CI: 33-63% overall was driven by predominant H3N2 activity for which VE was 41% (95%CI: 17-59%. All H3N2 field isolates were HI-characterized as well-matched to the WHO-recommended A/Victoria/361/2011 prototype whereas all but one were antigenically distinct from the egg-adapted strain as per actually used in vaccine production. The egg-adapted strain was itself antigenically distinct from the WHO-recommended prototype, and bore three AA mutations at antigenic sites B [H156Q, G186V] and D [S219Y]. Conversely, circulating viruses were identical to the WHO-recommended prototype at these positions with other genetic variation that did not affect antigenicity. VE was 59% (95%CI:16-80% against A(H1N1pdm09, 67% (95%CI: 30-85% against B

  20. 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.

  1. A Single 17D Yellow Fever Vaccination Provides Lifelong Immunity; Characterization of Yellow-Fever-Specific Neutralizing Antibody and T-Cell Responses after Vaccination

    NARCIS (Netherlands)

    Wieten, Rosanne W.; Jonker, Emile F. F.; van Leeuwen, Ester M. M.; Remmerswaal, Ester B. M.; ten Berge, Ineke J. M.; de Visser, Adriëtte W.; van Genderen, Perry J. J.; Goorhuis, Abraham; Visser, Leo G.; Grobusch, Martin P.; de Bree, Godelieve J.

    2016-01-01

    Prompted by recent amendments of Yellow Fever (YF) vaccination guidelines from boost to single vaccination strategy and the paucity of clinical data to support this adjustment, we used the profile of the YF-specific CD8+ T-cell subset profiles after primary vaccination and neutralizing antibodies as

  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. Enhanced immune response of red deer (Cervus elaphus) to live rb51 vaccine strain using composite microspheres.

    Science.gov (United States)

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

    2009-01-01

    Brucellosis is an important zoonotic disease of nearly worldwide distribution. The occurrence of the infection in humans is largely dependent on the prevalence of brucellosis in animal reservoirs, including wildlife. The current vaccine used for cattle Brucella abortus strain RB51, has proven ineffective in protecting bison (Bison bison) and elk (Cervus nelsoni) from infection and abortion. To test possible improvements in vaccine efficacy, a novel approach of immunization was examined from April 2004 to November 2006 using alginate composite microspheres containing a nonimmunogenic, eggshell-precursor protein of the parasite Fasciola hepatica (Vitelline protein B, VpB) to deliver live vaccine strain RB51. Red deer (Cervus elaphus), used as a model for elk, were vaccinated orally (PO) or subcutaneously (SC) with 1.5x10(10) viable organisms per animal. Humoral responses postvaccination (immunoglobulin G [IgG] levels), assessed at different time points, indicated that capsules containing live RB51 elicited an anti-Brucella specific IgG response. Furthermore, the encapsulated vaccine elicited a cell-mediated response that the nonencapsulated vaccinates failed to produce. Finally, red deer were challenged with B. abortus strain 19 by conjunctival exposure. Only animals that received encapsulated RB51 vaccine by either route exhibited a significant reduction in bacterial counts in their spleens. These data suggest that alginate-VpB microspheres provide a method to enhance the RB51 vaccine performance in elk.

  4. Long-term immunity in young adults after a single dose of inactivated Hepatitis A vaccines.

    Science.gov (United States)

    Orr, Nadav; Klement, Eyal; Gillis, David; Sela, Tamar; Kayouf, Raid; Derazne, Estela; Grotto, Itamar; Balicer, Ran; Huerta, Michael; Aviram, Lisa; Ambar, Ruhama; Epstein, Yoram; Heled, Yuval; Cohen, Dani

    2006-05-15

    We evaluated in a prospective study the immune response of naïve subjects to a single dose of inactivated Hepatitis A vaccine. Ninety-seven percent of the vaccinees sero-converted 1 month after vaccination and 93% were still positive 2 years later. All of the vaccinees had a strong booster response 2 years after the single dose. Avaxim was more immunogenic than Vaqta for the primary dose (p = 0.01 for sero-positivity, p<0.001 for antibody level) but no differences were found after boosting with Avaxim. Performance of intense physical activity during the first month after a single vaccine dose was associated with lower antibody levels (p = 0.004). This study indicates that a single dose of inactivated HAV vaccine elicits protective immune memory for at least 2 years.

  5. Evaluation of Factors Influencing Efficacy of Vaccine Strain CVI988 Against Marek's Disease in Meat-Type Chickens.

    Science.gov (United States)

    Gimeno, Isabel M; Cortes, Aneg L; Faiz, Nik M; Barbosa, Taylor; Villalobos, Tarsicio

    2015-09-01

    Marek's disease (MD) strain CVI988 is the most-protective commercially available vaccine against very virulent plus (vv+) Marek's disease virus (MDV). However, its use in meat-type chickens has been controversial. While several countries have been using CVI988 for more than 40 yr, others do not authorize its use or it is restricted mainly to layers. The use of CVI988 in meat-type chickens will be necessary in the future in areas where other vaccine protocols fail. The objective of this study was to evaluate factors (vaccine dose, vaccine origin, chicken genetics, age and route of vaccination, and combination with other MD vaccines) influencing the efficacy of CVI988 against MD in meat-type chickens. Three animal experiments were conducted in which various vaccine protocols using CVI988 were tested for their protection against challenge with vv+ strain 648A by contact at day of age. Experiments 1 and 2 were to compare the efficacy of CVI988 vaccines from three different origins (CVI988-A, CVI988-B, and CVI988-C) and evaluate the effect of vaccine dose and chicken genetics. Experiment 3 was to evaluate the effect of adding CVI988 vaccine to various vaccine protocols using other MD vaccines of serotypes 2 (SB-1) and 3 (rHVT). Our results show that, regardless of the origin of the vaccine, protection against early challenge with 648A was good when vaccines were administered at a high dose (>3000 plaque-forming units [PFU]). Differences among vaccines, however, were detected even when using a high dose in experiment 2 (vaccine CVI988-B conferred higher protection than did CVI988-C) but not in Experiment 1 (CVI988-B was compared to CVI988-A). The use of a fixed low dose (2000 PFU) of vaccine resulted in reduction in protection, and such reduction was more remarkable when using CV1988-A. No statistically significant differences were found when we compared the efficacy of CVI988 in two different genetic lines of broiler chickens (G1 and G2). Vaccination protocols that

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

    Science.gov (United States)

    Whitehead, Stephen S

    2016-01-01

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

  7. Environmental hazard assessment of Venezuelan equine encephalitis virus vaccine candidate strain V3526.

    Science.gov (United States)

    Rao, Venkat; Hinz, Matthew E; Roberts, Brian A; Fine, Donald

    2004-06-30

    A hazard assessment of Venezuelan equine encephalitis (VEE) virus sub-types and vaccine candidates was performed according to standard risk assessment procedures. Data from published literature demonstrates a considerable degree of safety of V3526 when compared to TC-83 vaccine, the protective measure that has been used to protect laboratory workers for over four decades. V3526 is a new recombinant vaccine candidate that is a vastly different product with a diminished hazard to public health and the general environment. A weight-of-evidence (WOE)-based scheme was employed to assign weights for relevance, quality, and adequacy of evidence in published literature on medical pathology, epidemiology, pre-clinical investigational studies, and environmental studies. The results of this assessment indicated that V3526 has a low adverse impact on public health and the general environment. Although there are currently no human infectivity or pathogenicity data for V3526, existing evidence from published experimental animal studies reveals a diminished hazard for environmental transmission and distribution. Recently, the US Centers for Disease Control and Prevention (CDC) excluded V3526 from select agent requirements set forth under the Health and Human Services (HHS) regulations in Title 42 C.F.R. Part 73 and the US Department Agriculture (USDA) regulations set forth in Title 7 C.F.R. Part 331 and Title 9 C.F.R. Part 121. This paper summarizes the background, rationale, and hazard analysis used for assessing the environmental hazard of the VEE vaccine candidate strain V3526.

  8. 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.

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

    Science.gov (United States)

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

    1999-01-01

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

  10. Vaccination with a live multi-gene deletion strain protects horses against virulent challenge with Streptococcus equi.

    Science.gov (United States)

    Robinson, Carl; Heather, Zoe; Slater, Josh; Potts, Nicola; Steward, Karen F; Maskell, Duncan J; Fontaine, Michael C; Lee, Jeong-Jin; Smith, Ken; Waller, Andrew S

    2015-02-25

    Strangles, caused by Streptococcus equi subspecies equi (S. equi) is one of the most frequently diagnosed infectious diseases of horses and there remains a significant need to develop new preventative vaccines. We generated a live vaccine strain of S. equi containing deletions in six genes: sagA, hasA, aroB, pyrC, seM and recA, which was administered to nine Welsh mountain ponies via the intramuscular route. Four vaccinated ponies developed adverse reactions following the first vaccination from which the live vaccine strain was isolated. Two of these ponies were withdrawn from the study and seven ponies received a second vaccination, one of which then developed an adverse reaction. Nine control ponies injected with culture media alone developed no adverse reactions. Following challenge with a virulent strain of S. equi, none of the seven vaccinated ponies had developed clinical signs of strangles eleven days post-challenge, compared to six of nine control ponies over the same period (P=0.0114). A lymph node abscess was identified in one of the seven vaccinated ponies at post-mortem examination, whilst all nine control ponies had at least one lymph node abscess (P=0.0009). Three of the six vaccinated ponies that were protected from strangles had not developed an adverse reaction following vaccination, suggesting that a better understanding of the pro-inflammatory responses to S. equi could lead to the development of a live attenuated vaccine against strangles that is safe for administration via intramuscular injection. Copyright © 2015 Elsevier Ltd. All rights reserved.

  11. 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.

  12. 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.

  13. Efficacy of strain RB51 vaccine in protecting infection and vertical transmission against Brucella abortus in Sprague-Dawley rats.

    Science.gov (United States)

    Islam, Md Ariful; Khatun, Mst Minara; Baek, Byeong-Kirl; Lee, Sung-Il

    2009-09-01

    Immunizing animals in the wild against Brucella (B.) abortus is essential to control bovine brucellosis because cattle can get the disease through close contact with infected wildlife. The aim of this experiment was to evaluate the effectiveness of the B. abortus strain RB51 vaccine in protecting infection as well as vertical transmission in Sprague-Dawley (SD) rats against B. abortus biotype 1. Virgin female SD rats (n = 48) two months of age were divided into two groups: one group (n = 24) received RB51 vaccine intraperitoneally with 3 x 10(10) colony forming units (CFU) and the other group (n = 24) was used as non-vaccinated control. Non-vaccinated and RB51-vaccinated rats were challenged with 1.5 x 10(9) CFU of virulent B. abortus biotype 1 six weeks after vaccination. Three weeks after challenge, all rats were bred. Verification of RB51-vaccine induced protection in SD rats was determined by bacteriological, serological and molecular screening of maternal and fetal tissues at necropsy. The RB51 vaccine elicited 81.25% protection in SD rats against infection with B. abortus biotype 1. Offspring from rats vaccinated with RB51 had a decreased (p RB51 vaccination efficacy against the vertical transmission of B. abortus in the SD rat model.

  14. The acceptability of three vaccine injections given to infants during a single clinic visit in South Africa

    OpenAIRE

    Tabana, Hanani; Dudley, Lilian D.; Knight, Stephen; Cameron, Neil; Mahomed, Hassan; Goliath, Charlyn; Eggers, Rudolf; Wiysonge, Charles S.

    2016-01-01

    Abstract Background The Expanded Programme on Immunisation (EPI) has increased the number of antigens and injections administered at one visit. There are concerns that more injections at a single immunisation visit could decrease vaccination coverage. We assessed the acceptability and acceptance of three vaccine injections at a single immunisation visit by caregivers and vaccinators in South Africa. Methods A mixed methods exploratory study of caregivers and vaccinators at clinics in two prov...

  15. Anti-botulism single-shot vaccine using chitosan for protein encapsulation by simple coacervation.

    Science.gov (United States)

    Sari, Roger S; de Almeida, Anna Christina; Cangussu, Alex S R; Jorge, Edson V; Mozzer, Otto D; Santos, Hércules Otacílio; Quintilio, Wagner; Brandi, Igor Viana; Andrade, Viviane Aguiar; Miguel, Angelo Samir M; Sobrinho Santos, Eliane M

    2016-12-01

    The aim of the present study was to compare the potency and safety of vaccines against Clostridium botulinum (C. botulinum) type C and D formulated with chitosan as controlled release matrix and vaccines formulated in conventional manner using aluminum hydroxide. Parameters were established for the development of chitosan microspheres, using simple coacervation to standardize the use of this polymer in protein encapsulation for vaccine formulation. To formulate a single shot vaccine inactivated antigens of C. botulinum type C and D were used with original toxin titles equal to 5.2 and 6.2 log LD50/ml, respectively. For each antigen a chitosan based solution of 50 mL was prepared. Control vaccines were formulated by mixing toxoid type C and D with aluminum hydroxide [25% Al(OH) 3 , pH 6.3]. The toxoid sterility, innocuity and potency of vaccines were evaluated as stipulated by MAPA-BRASIL according to ministerial directive no. 23. Encapsulation efficiency of BSA in chitosan was 32.5-40.37%, while that the encapsulation efficiency to toxoid type C was 41,03% (1.94 mg/mL) and of the toxoid type D was 32.30% (1.82 mg/mL). The single shot vaccine formulated using chitosan for protein encapsulation through simple coacervation showed potency and safety similar to conventional vaccine currently used in Brazilian livestock (10 and 2 IU/mL against C. botulinum type C and D, respectively). The present work suggests that our single shot vaccine would be a good option as a cattle vaccine against these C. botulinum type C and D. Copyright © 2016 Elsevier Ltd. All rights reserved.

  16. Protection from lethal herpes simplex virus type 1 infection by vaccination with a UL41-deficient recombinant strain.

    Science.gov (United States)

    Koshizuka, Tetsuo; Ishioka, Ken; Kobayashi, Takahiro; Ikuta, Kazufumi; Suzutani, Tatsuo

    2016-06-08

    The UL41 gene of herpes simplex virus type 1 (HSV-1) encodes a virion host shut off protein which is involved in immune evasion. The growth and virulence of HSV-1 is markedly reduced by the deletion of UL41. In this report, the UL41-deleted recombinant HSV-1 strain VR∆41 was evaluated as a prophylactic live attenuated vaccine against lethal HSV-1 infection in a mouse model. Intraperitoneal (i.p.) inoculation with the VR∆41 strain clearly inhibited lethal wild-type HSV-1 (VR-3 strain) infection after both i.p. and intracerebral (i.c.) inoculations. Vaccination with the VR∆41 strain was safer than VR-3 vaccination and was able to protect against a wild-type challenge to the same degree as VR-3 vaccination. In contrast, i.p. inoculation with ultraviolet-irradiated VR-3 induced resistance against i.p. infection, but not against i.c. Although replication of the VR∆41 strain in mice was greatly reduced compared to that of the VR-3 strain, VR∆41 strain maintained the ability to spread to the central nervous system (CNS) from a peripheral inoculation site. These results indicated that the VR∆41 strain evoked a potent immune reaction through viral protein expression within CNS without the induction of lethal encephalitis. The entry of antigens into the CNS was essential for the establishment of protective immunity against the lethal HSV encephalitis. We concluded that only a live attenuated vaccine is able to afford a prophylactic effect against CNS infection with HSV. In order to fulfill this requirement, UL41-deleted viruses provide a strong candidate for use as a recombinant live vaccine.

  17. 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.

  18. 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.

  19. Cloning of Nucleoprotein Gene (NP) of Rinderpest Virus (RPV) RBOK Vaccine Strain

    OpenAIRE

    TONBAK, Şükrü

    2005-01-01

    In the present study cloning of the NP gene in a cloning vector is reported. For this purpose, Vero cells were infected with rinderpest RBOK vaccine strain. Total RNA was obtained from the infected cells and reverse-transcription (RT) was performed to get cDNAs of NP gene. Afterwards, the NP gene was amplified by polymerase chain reaction (PCR) with the primers specific to the NP gene. The NP gene, 1575 bp in length, was cloned into pGEM-3Zf (-) cloning vector. PCR screening and enzyme digest...

  20. Single shot of 17D vaccine may not confer life-long protection against yellow fever.

    Science.gov (United States)

    Vasconcelos, Pedro Fc

    2018-02-01

    The yellow fever (YF) vaccine has been used since the 1930s to prevent YF, which is a severe infectious disease caused by the yellow fever virus (YFV), and mainly transmitted by Culicidae mosquitoes from the genera Aedes and Haemagogus . Until 2013, the World Health Organization (WHO) recommended the administration of a vaccine dose every ten years. A new recommendation of a single vaccine dose to confer life-long protection against YFV infection has since been established. Recent evidence published elsewhere suggests that at least a second dose is needed to fully protect against YF disease. Here, we discuss the feasibility of administering multiple doses, the necessity for a new and modern vaccine, and recommend that the WHO conveys a meeting to discuss YFV vaccination strategies for people living in or travelling to endemic areas.

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

    Directory of Open Access Journals (Sweden)

    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

  2. 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.

    2016-01-01

    Background 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. Purpose 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. Methods 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. Results 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 subfamily 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. Conclusions 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. PMID

  3. 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

  4. 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.

  5. The acceptability of three vaccine injections given to infants during a single clinic visit in South Africa.

    Science.gov (United States)

    Tabana, Hanani; Dudley, Lilian D; Knight, Stephen; Cameron, Neil; Mahomed, Hassan; Goliath, Charlyn; Eggers, Rudolf; Wiysonge, Charles S

    2016-08-08

    The Expanded Programme on Immunisation (EPI) has increased the number of antigens and injections administered at one visit. There are concerns that more injections at a single immunisation visit could decrease vaccination coverage. We assessed the acceptability and acceptance of three vaccine injections at a single immunisation visit by caregivers and vaccinators in South Africa. A mixed methods exploratory study of caregivers and vaccinators at clinics in two provinces of South Africa was conducted. Quantitative and qualitative data were collected using questionnaires as well as observations of the administration of three-injection vaccination sessions. The sample comprised 229 caregivers and 98 vaccinators. Caregivers were satisfied with the vaccinators' care (97 %) and their infants receiving immunisation injections (93 %). However, many caregivers, (86 %) also felt that three or more injections were excessive at one visit. Caregivers had limited knowledge of actual vaccines provided, and reasons for three injections. Although vaccinators recognised the importance of informing caregivers about vaccination, they only did this sometimes. Overall, acceptance of three injections was high, with 97 % of caregivers expressing willingness to bring their infant for three injections again in future visits despite concerns about the pain and discomfort that the infant experienced. Many (55 %) vaccinators expressed concern about giving three injections in one immunisation visit. However, in 122 (95 %) observed three-injection vaccination sessions, the vaccinators administered all required vaccinations for that visit. The remaining seven vaccinations were not completed because of vaccine stock-outs. We found high acceptance by caregivers and vaccinators of three injections. Caregivers' poor understanding of reasons for three injections resulted from limited information sharing by vaccinators for caregivers. Acceptability of three injections may be improved through

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

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    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

  7. 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.

  8. Multivalent rotavirus vaccine and wild-type rotavirus strain shedding in Australian infants: a birth cohort study.

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    Ye, Suifang; Whiley, David M; Ware, Robert S; Kirkwood, Carl D; Lambert, Stephen B; Grimwood, Keith

    2017-11-15

    Rotavirus vaccines have reduced moderate-to-severe gastroenteritis episodes in infants and young children. Nevertheless, knowledge gaps exist concerning rotavirus vaccine shedding and vaccine impact upon mild and asymptomatic wild-type infections. Our primary objective was to investigate vaccine shedding in Australian infants where the multivalent human-bovine reassortant rotavirus vaccine, RotaTeq®, was part of the routine vaccination schedule. The Observational Research in Childhood Infectious Diseases (ORChID) birth cohort study was conducted in Brisbane, Australia, from September 2010 to October 2014. Newborn infants were enrolled progressively and followed until their second birthday. Parents recorded daily symptoms and mailed weekly stool swab samples from their infants to the laboratory where reverse transcription-polymerase chain reaction (RT-PCR) testing was performed, and rotavirus-positive samples underwent genotyping to distinguish between vaccine and wild-type strains. Rotavirus was detected in 1,068/11,139 (9.6%) stool swabs from 158 infants, and 994 (93.1%) were genotyped. RotaTeq® vaccine strains accounted for 951/994 (95.7%) of typed rotavirus-positive swabs. Proportions of infants shedding RotaTeq® after the first, second and third vaccine doses were 87.0%, 57.4% and 47.3% respectively and median (interquartile range) shedding duration after vaccine doses 1-3 was 3 (1-8), 1.5 (1-3) and 1 (1-2) weeks respectively. In contrast, the incidence rate of wild-type rotavirus episodes was 10.3 (95% confidence interval 6.8-15.6) per 100 child-years of observation. RotaTeq® vaccine virus was detected in stool samples from 47-87% of infants after each vaccine dose. Genotyping is an essential tool for differentiating between rotavirus vaccine and wild-type strains and monitoring vaccine impact in children. © The Author 2017. Published by Oxford University Press for the Infectious Diseases Society of America. All rights reserved. For permissions, e

  9. Gumboro disease: evaluation of serological and anatomopathological responses in vaccinated broiler chickens challenged with very virulent virus strain

    Directory of Open Access Journals (Sweden)

    Bolis DA

    2003-01-01

    Full Text Available This paper describes the effects of a strong type of vaccine - Moulthrop G603 º and an intermediate-plus type of vaccine - 228E º in meat-type chickens challenged with a very virulent strain of infectious bursal disease virus (vvIBDV. Blood samples and bursa of Fabricius were taken weekly up to 42 days of age. It was concluded that bursa of Fabricius weight, bursa weight:body weight ratio, body weight and antibody titer evaluated before and after challenge with vvIBDV were not enough to consistently and conclusively differentiate or estimate the protection given by vaccination. Quantitative evaluation of injury intensity and the number of altered lymphoid follicles revealed that Moulthrop G603 caused moderate microscopic lesions in one out of seven birds vaccinated at 14 days of age, while 228E vaccine did not induce IBD-typical microscopic lesions in the bursa of Fabricius. Good protection against bursal microscopic lesions was obtained when a strong type of vaccine was used before challenging with vvIBDV. It was concluded that quantitative evaluation of microscopic lesions might be useful to measure the injury induced by vaccinal IBDV, as well as the level of protection and/or immunosuppression induced by IBDV challenge in vaccinated and non-vaccinated chickens.

  10. 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

  11. Evaluation of specific humoral immune response in pigs vaccinated intradermally with deleted Aujeszky's disease vaccine and challenged with virulent strain of Herpesvirus suis type 1.

    Science.gov (United States)

    Mikulska-Skupień, E; Szweda, W; Procajło, Z

    2005-01-01

    A comparison of intradermal (ID) versus intramuscular (IM) routes of pig vaccination with deleted Aujeszky's disease (AD) vaccine on the formation of specific postvaccinal and postchallenge humoral immune response was performed. The studies were carried out on 21 eight week-old piglets, divided into three groups--two experimental and one control of 7 piglets each. Animals of first two groups were vaccinated twice in 12 and 16 week of age with deleted, live attenuated AD vaccine Porcilis Begonia (Intervet). Group I was vaccinated with a dose of 2.0 ml (10(6.0) TCID50)) intramuscularly (IM) into neck muscles, and group II received 0.2 ml (10(5.0) TCID50) intradermally (ID) in neck area using needleless apparatus SERENA model SD 1-2 (Emplast, Italy). In group K (control) 2.0 ml PBS IM was used. Seventy days after the first vaccination all pigs were intranasally infected with a dose of 10(5.5) TCID50 of virulent Northern Ireland Aujeszky-3 (NIA-3) strain of Herpesvirus suis type 1 (SHV-1) by instilling 0.5 ml of virus suspension into each nostril. Specific humoral immune response was evaluated using seroneutralization (SN) test and gE-ELISA-Pseudorabies virus gpI Antibody Test Kit (Herd Chek Anti-PRV gpI), IDEXX Lab Inc (USA). It was found that challenge caused anamnestic reaction in both groups of vaccinated pigs, but postchallenge immune response was stronger in ID-vaccinated group--on 14 day post infection (dpi) SN antibody level was considerably higher than in IM-vaccinated group. The obtained results suggest that secondary immunological response after challenge is decidedly more effective in the range of evaluated parameters in animals vaccinated by ID route, which can be linked to, perhaps underestimated yet and seldom utilized, skin immunity mechanisms in specific prophylaxis of infectious diseases. Advantages and disadvantages of SN test and ELISA are also discussed.

  12. The pathogenic and vaccine strains of equine infectious anemia virus differentially induce cytokine and chemokine expression and apoptosis in macrophages.

    Science.gov (United States)

    Lin, Yue-Zhi; Cao, Xue-Zhi; Li, Liang; Li, Li; Jiang, Cheng-Gang; Wang, Xue-Feng; Ma, Jian; Zhou, Jian-Hua

    2011-09-01

    The attenuated equine infectious anemia virus (EIAV) vaccine was the first attenuated lentivirus vaccine to be used in a large-scale application and has been used to successfully control the spread of equine infectious anemia (EIA) in China. To better understand the potential role of cytokines in the pathogenesis of EIAV infection and resulting immune response, we used branched DNA technology to compare the mRNA expression levels of 12 cytokines and chemokines, including IL-1α, IL-1β, IL-4, IL-10, TNF-α, IFN-γ, IP-10, IL-8, MIP-1α, MIP-1β, MCP-1, and MCP-2, in equine monocyte-derived macrophages (eMDMs) infected with the EIAV(DLV121) vaccine strain or the parental EIAV(DLV34) pathogenic strain. Infection with EIAV(DLV34) and EIAV(DLV121) both caused changes in the mRNA levels of various cytokines and chemokines in eMDMs. In the early stage of infection with EIAV(DLV34) (0-24h), the expression of the pro-inflammatory cytokines TNF-α and IL-1β were significantly up-regulated, while with EIAV(DLV121), expression of the anti-inflammatory cytokine IL-4 was markedly up-regulated. The effects on the expression of other cytokines and chemokines were similar between these two strains of virus. During the first 4 days after infection, the expression level of IL-4 in cells infected with the pathogenic strain were significantly higher than that in cells infected with the vaccine strain, but the expression of IL-1α and IL-1β induced by the vaccine strain was significantly higher than that observed with the pathogenic strain. In addition, after 4 days of infection with the pathogenic strain, the expression levels of 5 chemokines, but not IP-10, were markedly increased in eMDMs. In contrast, the vaccine strain did not up-regulate these chemokines to this level. Contrary to our expectation, induced apoptosis in eMDMs infected with the vaccine strain was significantly higher than that infected with the pathogenic strain 4 days and 6 days after infection. Together, these

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

    Science.gov (United States)

    Herzog, Christian

    2016-01-01

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

  14. [Genetic changes in strains of poliovirus type 2 isolated from patients with vaccine-associated paralytic poliomyelitis].

    Science.gov (United States)

    Sosa-Díaz, R Y; Más-Lago, P; Valdés-Ramírez, O; Sarmiento-Pérez, L

    Poliomyelitis is currently a rare disease in developed countries, where only vaccinal strains seem to be in circulation, which replace wild poliovirus. Nevertheless, it is still a serious disease for children in underdeveloped countries of Asia and Africa. We analysed nine strains of poliovirus type 2 isolated from the faecal matter of patients with vaccine associated paralytic poliomyelitis (VAPP), from the beginning of anti polio vaccination campaigns in our country. These strains were submitted to sequencing of a fragment of 114 base pairs from the 5 NTR (non traductional region), where one of the main determinants of attenuation/reversion to the neurovirulence of poliovirus lies in the position of nucleotide 481. In this position it was observed how guanine had been replaced by adenine in all the strains that were sequenced, so that it coincided with the homologous sequence of the wild strain, as well as with that of strains obtained from healthy children immunised with the live vaccine. This presupposes that other changes must occur or that other factors must be involved for VAPP to occur or not, and we therefore suggest the sequencing of other regions of the genome in search of other possible differential changes in nucleotides.

  15. [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.

  16. 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.

  17. Isolation of Single-Domain Antibody Fragments That Preferentially Detect Intact (146S Particles of Foot-and-Mouth Disease Virus for Use in Vaccine Quality Control

    Directory of Open Access Journals (Sweden)

    Michiel M. Harmsen

    2017-08-01

    Full Text Available Intact (146S foot-and-mouth disease virus (FMDVs can dissociate into specific (12S viral capsid degradation products. FMD vaccines normally consist of inactivated virions. Vaccine quality is dependent on 146S virus particles rather than 12S particles. We earlier isolated two llama single-domain antibody fragments (VHHs that specifically recognize 146S particles of FMDV strain O1 Manisa and shown their potential use in quality control of FMD vaccines during manufacturing. These 146S-specific VHHs were specific for particular O serotype strains and did not bind strains from other FMDV serotypes. Here, we describe the isolation of 146S-specific VHHs against FMDV SAT2 and Asia 1 strains by phage display selection from llama immune libraries. VHHs that bind both 12S and 146S particles were readily isolated but VHHs that bind specifically to 146S particles could only be isolated by phage display selection using prior depletion for 12S particles. We obtained one 146S-specific VHH—M332F—that binds to strain Asia 1 Shamir and several VHHs that preferentially bind 146S particles of SAT2 strain SAU/2/00, from which we selected VHH M379F for further characterization. Both M332F and M379F did not bind FMDV strains from other serotypes. In a sandwich enzyme-linked immunosorbent assay (ELISA employing unlabeled and biotinylated versions of the same VHH M332F showed high specificity for 146S particles but M379F showed lower 146S-specificity with some cross-reaction with 12S particles. These ELISAs could detect 146S particle concentrations as low as 2.3–4.6 µg/l. They can be used for FMD vaccine quality control and research and development, for example, to identify virion stabilizing excipients.

  18. [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

  19. Circulation of a type 1 recombinant vaccine-derived poliovirus strain in a limited area in Romania.

    Science.gov (United States)

    Combiescu, M; Guillot, S; Persu, A; Baicus, A; Pitigoi, D; Balanant, J; Oprisan, G; Crainic, R; Delpeyroux, F; Aubert-Combiescu, A

    2007-01-01

    After intensive immunisation campaigns with the oral polio vaccine (OPV) as part of the Global Polio Eradication Initiative, poliomyelitis due to wild viruses has disappeared from most parts of the world, including Europe. Here, we report the characterization of a serotype 1 vaccine-derived poliovirus (VDPV) isolated from one acute flaccid paralysis (AFP) case with tetraplegia and eight healthy contacts belonging to the same small socio-cultural group having a low vaccine coverage living in a small town in Romania. The genomes of the isolated strains appeared to be tripartite type 1/type 2/type 1 vaccine intertypic recombinant genomes derived from a common ancestor strain. The presence of 1.2% nucleotide substitutions in the VP1 capsid protein coding region of most of the strains indicated a circulation time of about 14 months. These VDPVs were thermoresistant and, in transgenic mice expressing the human poliovirus receptor, appeared to have lost the attenuated phenotype. These results suggest that small populations with low vaccine coverage living in globally well-vaccinated countries can be the origin of VDPV emergence and circulation. These results reaffirm the importance of active surveillance for acute flaccid paralysis and poliovirus in both polio-free and polio-endemic countries.

  20. 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.

  1. 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

  2. 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...

  3. 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)

  4. 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.

  5. Assessment of efficacy of a live oral poliovirus vaccine for virulent Sabin-like poliovirus 1 strains in Japan.

    Science.gov (United States)

    Iwai, M; Nakayama, T; Matsuura, K; Hasegawa, S; Ando, S; Obara, M; Nagai, Y; Yoshida, H; Horie, H

    2006-01-01

    Virulent Sabin-like poliovirus (VSLP) was isolated from river and sewage waters between October 1993 and September 1995 in Toyama Prefecture, Japan (Yoshida et al., Lancet 356, 1461-1463, 2000). In this study, to assess the possibility of an epidemic of poliomyelitis caused by a VSLP in Japan under the current vaccination policy of administration of live attenuated oral poliovirus vaccine (OPV), we determined titers of serum neutralizing antibodies to poliovirus 1 (PV-1) strains Sabin (vaccine strain), Mahoney (wild-type strain) and G4-12 (VSLP) in various groups of residents of Toyama Prefecture, Japan. The seropositivity and geometric mean neutralizing antibody titers against these strains in the individuals who obtained two doses of OPV were 99.1%, 94.5% and 95.5%, respectively, and 564, 186 and 194, respectively. Although the antibody titers to G4-12 were lower compared with those to Sabin, these results indicate that the OPV vaccination policy in Japan has been effective in preventing poliomyelitis caused by VSLPs. These results also suggest that (i) an epidemic of poliomyelitis caused by a VSLP has not occurred in Japan due to herd immunity, and (ii) the possibility of reemergence of VSLPs will be prevented if sufficient herd immunity is acquired immediately after completion of the OPV vaccination in accordance with the poliomyelitis eradication program.

  6. Immune responses and protection against experimental challenge after vaccination of bison with Brucella abortus strain RB51 or RB51 overexpressing superoxide dismutase and glycosyltransferase genes.

    Science.gov (United States)

    Olsen, S C; Boyle, S M; Schurig, G G; Sriranganathan, N N

    2009-04-01

    Vaccination is a tool that could be beneficial in managing the high prevalence of brucellosis in free-ranging bison in Yellowstone National Park. In this study, we characterized immunologic responses and protection against experimental challenge after vaccination of bison with Brucella abortus strain RB51 (RB51) or a recombinant RB51 strain overexpressing superoxide dismutase (sodC) and glycosyltransferase (wboA) genes (RB51+sodC,wboA). Bison were vaccinated with saline only or with 4.6 x 10(10) CFU of RB51 or 7.4 x 10(10) CFU of RB51+sodC,wboA (n = eight animals/treatment). Bison vaccinated with RB51 or RB51+sodC,wboA had greater (P RB51 after vaccination than did nonvaccinates. However, bison vaccinated with RB51+sodC,wboA cleared the vaccine strain from draining lymph nodes faster than bison vaccinated with the parental RB51 strain. Immunologic responses of bison vaccinated with RB51+sodC,wboA were similar to responses of bison vaccinated with RB51. Pregnant bison were intraconjunctivally challenged in midgestation with 10(7) CFU of B. abortus strain 2308. Bison vaccinated with RB51, but not RB51+sodC,wboA vaccinates, had greater protection from abortion, fetal/uterine, mammary, or maternal infection than nonvaccinates. Our data suggest that the RB51+sodC,wboA strain is less efficacious as a calfhood vaccine for bison than the parental RB51 strain. Our data also suggest that the RB51 vaccine is a currently available management tool that could be utilized to help reduce brucellosis in free-ranging bison.

  7. Efficacy of Fostera PRRS modified live virus vaccine against a Canadian heterologous virulent field strain of porcine reproductive and respiratory syndrome virus.

    Science.gov (United States)

    Savard, Christian; Alvarez, Fernando; Provost, Chantale; Chorfi, Younes; D'Allaire, Sylvie; Benoit-Biancamano, Marie-Odile; Gagnon, Carl A

    2016-01-01

    Vaccination is a useful option to control infection with porcine reproductive and respiratory syndrome virus (PRRSV), and several modified live-PRRSV vaccines have been developed. These vaccines have shown some efficacy in reducing the incidence and severity of clinical disease as well as the duration of viremia and virus shedding but have failed to provide sterilizing immunity. The efficacy of modified live-virus (MLV) vaccines is greater against a homologous strain compared with heterologous PRRSV strains. The objective of this study was to evaluate the efficacy of Fostera PRRS MLV vaccine in protecting against challenge with a heterologous field strain widely circulating in the swine herds of eastern Canada. Forty-six piglets were divided into 4 groups: nonvaccinated-nonchallenged; nonvaccinated-challenged; vaccinated-challenged; and vaccinated-nonchallenged. The animals were vaccinated at 23 d of age with Fostera PRRS and challenged 23 d later with a heterologous field strain of PRRSV (FMV12-1425619). Overall, the vaccine showed some beneficial effects in the challenged animals by reducing the severity of clinical signs and the viral load. A significant difference between nonvaccinated and vaccinated animals was detected for some parameters starting 11 to 13 d after challenge, which suggested that the cell-mediated immune response or other delayed responses could be more important than pre-existing PRRSV antibodies in vaccinated animals within the context of protection against heterologous strains.

  8. A new BVDV type I inactivated vaccine (PregSure((R)) BVD): Broad cross neutralisation of type I and type IIBVDV strains and significant improvement of pregnancy rates

    NARCIS (Netherlands)

    Salt, J.S.; Antonis, A.F.G.; Peters, A.R.; Brune, A.; Jahnecke, S.; Traeder, W.; Harmeyer, S.S.

    2004-01-01

    Objective: Aim of the present study was to demonstrate the relevance of the vaccine strain of a new BVD vaccine, PregSure® BVD, for its use in Europe. Furthermore the vaccine¿s ability to protect from pregnancy losses due to an early infection with BVDV after artificial insemination was determined.

  9. Reduced lung lesions in pigs challenged 25 weeks after the administration of a single dose of Mycoplasma hyopneumoniae vaccine at approximately 1 week of age.

    Science.gov (United States)

    Reynolds, S C; St Aubin, L B; Sabbadini, L G; Kula, J; Vogelaar, J; Runnels, P; Peters, A R

    2009-09-01

    Two independent studies assessed the duration of immunity of an inactivated adjuvanted Mycoplasma hyopneumoniae vaccine against mycoplasmal pneumonia in seronegative (study A, n=52) and seropositive (study B, n=52) pigs. The pigs were allocated randomly to treatment and were then injected with a single dose of either the vaccine or a placebo at approximately 1 week of age. Twenty-five weeks after treatment administration, the pigs were challenged with a virulent strain (LI 36, Strain 232) of M. hyopneumoniae and the extent of lung lesions consistent with mycoplasmal pneumonia was assessed 4 weeks later. In study A, the geometric mean lung lesion score (expressed as least squares mean percentages of lung lesions) was significantly (P=0.0001) lower in vaccinated (0.3%, n=20) than in control pigs (5.9%, n=24) seronegative to M. hyopneumoniae at enrolment; similarly, in study B, the extent of lung lesions was significantly reduced (P=0.0385) in seropositive vaccinated pigs (2.0%, n=22) compared to controls (4.5%, n=26). At the end of the investigation period, 4 weeks after challenge, mean antibody sample-to-positive (S/P) ratios were significantly higher both in seronegative (P=0.0012) and seropositive (P=0.0001) vaccinated pigs (mean values=0.77 and 0.81, respectively) than in controls (mean values=0.51 and 0.38, respectively).

  10. 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.

    2011-01-01

    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. PMID:21807911

  11. Comparison of 2 commercial single-dose Mycoplasma hyopneumoniae vaccines and porcine reproductive and respiratory syndrome virus (PRRSV) vaccines on pigs dually infected with M. hyopneumoniae and PRRSV.

    Science.gov (United States)

    Park, Changhoon; Kang, Ikjae; Seo, Hwi Won; Jeong, Jiwoon; Choi, Kyuhyung; Chae, Chanhee

    2016-04-01

    The objective of this study was to compare the efficacy of 2 different commercial Mycoplasma hyopneumoniae vaccines and porcine reproductive and respiratory syndrome virus (PRRSV) vaccines in regard to growth performance, microbiological and immunological analyses, and pathological observation from wean to finish (175 d of age). Pigs were administered M. hyopneumoniae and PRRSV vaccines at 7 and 21 d of age, respectively, or both at 21 d old and then challenged with both M. hyopneumoniae and PRRSV at 49 d old. Significant (P hyopneumoniae, M. hyopneumoniae-specific interferon-γ secreting cells, and macroscopic and microscopic lung lesions. Induction of interleukin-10 following PRRSV vaccination does not interfere with the immune responses induced by M. hyopneumoniae vaccine. The present study demonstrated that the single-dose vaccination regimen for M. hyopneumoniae and PRRSV vaccine is efficacious for controlling coinfection with M. hyopneumoniae and PRRSV based on clinical, microbiological, immunological, and pathological evaluation.

  12. An inactivated hand-foot-and-mouth disease vaccine using the enterovirus 71 (C4a) strain isolated from a Korean patient induces a strong immunogenic response in mice.

    Science.gov (United States)

    In, Hyun Ju; Lim, Heeji; Lee, Jung-Ah; Kim, Hye Jin; Kim, Jin-Won; Hyeon, Ji-Yeon; Yeo, Sang-Gu; Lee, June-Woo; Yoo, Jung Sik; Choi, Young Ki; Lee, Sang-Won

    2017-01-01

    Enterovirus 71 (EV71) is a major causative agent of hand-foot-and-mouth disease (HFMD) frequently occurring in children. HFMD induced by EV71 can cause serious health problems and has been reported worldwide, particularly in the Asia-Pacific region. In this study, we assessed the immunogenicity of a formalin-inactivated HFMD vaccine using an EV71 strain (FI-EV71 C4a) isolated from a Korean patient. The vaccine candidate was evaluated in mice to determine the vaccination doses and vaccine schedules. BALB/c mice were intramuscularly administered 5, 10, or 20 μg FI-EV71 vaccine, followed by a booster 2 weeks later. EV71-specific antibodies and neutralizing antibodies were induced and maintained until the end of the experimental period in all vaccinated groups. To determine the effectiveness of adjuvant for the EV71 vaccine, three adjuvants, i.e., aluminium hydroxide gel, monophosphoryl lipid A, and polyinosinic-polycytidylic acid, were administered separately with the FI-EV71 vaccine to mice via the intramuscular route. Mice administered the FI-EV71 vaccine formulated with all three adjuvants induced a significantly increased antibody response compared with that of the single adjuvant groups. The vaccinated group with triple adjuvants exhibited more rapid induction of EV71-specific and neutralizing antibodies than the other groups. These results suggested that the role of adjuvant in inactivated vaccine was important for eliciting effective immune responses against EV71. In conclusion, our results showed that FI-EV71 was a potential candidate vaccine for prevention of EV71 infection.

  13. Immunogenicity and safety of a quadrivalent inactivated influenza vaccine compared with two trivalent inactivated influenza vaccines containing alternate B strains in adults: A phase 3, randomized noninferiority study.

    Science.gov (United States)

    Treanor, John T; Albano, Frank R; Sawlwin, Daphne C; Graves Jones, Alison; Airey, Jolanta; Formica, Neil; Matassa, Vince; Leong, Jane

    2017-04-04

    Vaccination is the most effective means of influenza prevention. Efficacy of trivalent vaccines may be enhanced by including both B strain lineages. This phase 3, double-blind study assessed the immunogenicity and safety/tolerability of a quadrivalent inactivated influenza vaccine (IIV4) versus the United States (US)-licensed 2014-2015 trivalent inactivated influenza vaccine (IIV3-Yamagata [IIV3-YAM]; Afluria) and IIV3 containing the alternate Victoria B strain (IIV3-VIC) in adults ≥18years. Participants (n=3484) were randomized 2:1:1 and stratified by age to receive IIV4 (n=1741), IIV3-YAM (n=871), or IIV3-VIC (n=872). The primary objective was to demonstrate noninferiority of the immunological response to IIV4 versus IIV3-YAM and IIV3-VIC. Noninferiority was assessed by hemagglutination inhibition geometric mean titer (GMT) ratio (IIV3/IIV4; upper bound of two-sided 95% confidence interval [CI]≤1.5) and seroconversion rate (SCR) difference (IIV3 - IIV4; upper bound of two-sided 95% CI≤10%) for vaccine strains. Solicited local and systemic adverse events (AEs) were assessed for 7days postvaccination, AEs recorded for 28days postvaccination, and serious AEs for 6months postvaccination. IIV4 elicited a noninferior immune response for matched strains, and superior response for unmatched B strains not contained in IIV3 comparators. Adjusted GMT ratios (95% CI) for A/H1N1, A/H3N2, B/YAM, and B/VIC strains were 0.93 (0.88, 0.99), 0.93 (0.88, 0.98), 0.87 (IIV3-YAM; 0.82, 0.93), and 0.95 (IIV3-VIC; 0.88, 1.03), respectively. Corresponding values for SCR differences (95% CI) were -1.1 (-4.5, 2.3), -1.7 (-5.0, 1.7), -3.2 (IIV3-YAM; -7.4, 0.9), and -1.6 (IIV3-VIC; -5.8, 2.5). AEs were generally mild and experienced by 52.9% of participants. Serious AEs were reported with a slightly higher frequency with IIV4 (2.3%) versus IIV3-YAM (1.6%) and IIV3-VIC (1.5%). IIV4 demonstrated immunological noninferiority to the US-licensed IIV3, and superiority for unmatched B strains

  14. A chimeric dengue virus vaccine using Japanese encephalitis virus vaccine strain SA14-14-2 as backbone is immunogenic and protective against either parental virus in mice and nonhuman primates.

    Science.gov (United States)

    Li, Xiao-Feng; Deng, Yong-Qiang; Yang, Hui-Qiang; Zhao, Hui; Jiang, Tao; Yu, Xue-Dong; Li, Shi-Hua; Ye, Qing; Zhu, Shun-Ya; Wang, Hong-Jiang; Zhang, Yu; Ma, Jie; Yu, Yong-Xin; Liu, Zhong-Yu; Li, Yu-Hua; Qin, E-De; Shi, Pei-Yong; Qin, Cheng-Feng

    2013-12-01

    The development of a safe and efficient dengue vaccine represents a global challenge in public health. Chimeric dengue viruses (DENV) based on an attenuated flavivirus have been well developed as vaccine candidates by using reverse genetics. In this study, based on the full-length infectious cDNA clone of the well-known Japanese encephalitis virus live vaccine strain SA14-14-2 as a backbone, a novel chimeric dengue virus (named ChinDENV) was rationally designed and constructed by replacement with the premembrane and envelope genes of dengue 2 virus. The recovered chimeric virus showed growth and plaque properties similar to those of the parental DENV in mammalian and mosquito cells. ChinDENV was highly attenuated in mice, and no viremia was induced in rhesus monkeys upon subcutaneous inoculation. ChinDENV retained its genetic stability and attenuation phenotype after serial 15 passages in cultured cells. A single immunization with various doses of ChinDENV elicited strong neutralizing antibodies in a dose-dependent manner. When vaccinated monkeys were challenged with wild-type DENV, all animals except one that received the lower dose were protected against the development of viremia. Furthermore, immunization with ChinDENV conferred efficient cross protection against lethal JEV challenge in mice in association with robust cellular immunity induced by the replicating nonstructural proteins. Taken together, the results of this preclinical study well demonstrate the great potential of ChinDENV for further development as a dengue vaccine candidate, and this kind of chimeric flavivirus based on JE vaccine virus represents a powerful tool to deliver foreign antigens.

  15. Determination of efficacious vaccine seed strains for use against Egyptian H5N1 highly pathogenic avian influenza viruses through antigenic cartography and in vivo challenge studies

    Science.gov (United States)

    Since 2006, there have been reported outbreaks of H5N1 highly pathogenic avian influenza (HPAI) in vaccinated chickens in Africa and Asia. This study provides experimental data for selection of efficacious H5N1 vaccine seed strains against recently circulating strains of H5N1 HPAI viruses in Egypt....

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

    Directory of Open Access Journals (Sweden)

    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.

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

    Science.gov (United States)

    Berrêdo-Pinho, Marcia; Kalume, Dario E; Correa, Paloma R; Gomes, Leonardo H F; Pereira, Melissa P; da Silva, Renata F; Castello-Branco, Luiz R R; Degrave, Wim M; Mendonça-Lima, Leila

    2011-04-20

    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. 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. 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.

  18. Immune response in cattle vaccinated against rabies

    Directory of Open Access Journals (Sweden)

    Oliveira Alexandre Nunes de

    2000-01-01

    Full Text Available In order to determine the best type of rabies vaccine to use as a booster, 78 serological samples from singly vaccinated cattle were analyzed by counterimmunoelectrophoresis technique. The animals were divided into several groups, received the first vaccine dose with modified live virus vaccine (ERA strain and were revaccinated with inactivated virus or modified live virus vaccines. Boosters were given at 2, 4, 8, 12 and 16 weeks following first vaccination. Results showed high titres in the cases of booster with inactivated vaccine. In all cases, however, detectable antibody titres declined quickly.

  19. 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

    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. 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. The prevalence of rotavirus was higher in cases (32.5%) than in controls (7.7%, Pcases and G1, G12 and G8 in controls. The Tanzanian G1 variants displayed 94% similarity with the Rotarix vaccine G1 variant. The commonest P genotypes were P[8], P[4] and P[6], and the commonest G/P combination G1 P[8] (n = 123), G8 P[4] and G12 P[6]. Overall, rotavirus 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, Pvaccination study shows predominance of genotype G1 in Tanzania, which is phylogenetically distantly related to the vaccine strains. We confirm the emergence of genotype G8 and G12. Rotavirus infection and circulating genotypes showed seasonal variation. This study also suggests that rotavirus may not be an opportunistic pathogen in children infected with HIV.

  20. 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).

  1. A single dose of the novel chimeric subunit vaccine E2-CD154 confers early full protection against classical swine fever virus.

    Science.gov (United States)

    Suárez, Marisela; Sordo, Yusmel; Prieto, Yanet; Rodríguez, María P; Méndez, Lídice; Rodríguez, Elsa M; Rodríguez-Mallon, Alina; Lorenzo, Elianet; Santana, Elaine; González, Nemecio; Naranjo, Paula; Frías, María Teresa; Carpio, Yamila; Estrada, Mario Pablo

    2017-08-03

    Classical swine fever is an economically important, highly contagious disease of swine worldwide. Subunit vaccines are a suitable alternative for the control of classical swine fever. However, such vaccines have as the main drawback the relatively long period of time required to induce a protective response, which hampers their use under outbreak conditions. In this work, a lentivirus-based gene delivery system is used to obtain a stable recombinant HEK 293 cell line for the expression of E2-CSFV antigen fused to porcine CD154 as immunostimulant molecule. The E2-CD154 chimeric protein was secreted into the medium by HEK293 cells in a concentration around 50mg/L in suspension culture conditions using spinner bottles. The E2-CD154 immunized animals were able to overcome the challenge with a high virulent CSF virus strain performed 7days after a unique dose of the vaccine without clinical manifestations of the disease. Specific anti-CSFV neutralizing antibodies and IFN-γ were induced 8days after challenge equivalent to 14days post-vaccination. The present work constitutes the first report of a subunit vaccine able to confer complete protection by the end of the first week after a single vaccination. These results suggest that the E2-CD154 antigen could be potentially used under outbreak conditions to stop CSFV spread and for eradication programs in CSF enzootic areas. Copyright © 2017 Elsevier Ltd. All rights reserved.

  2. 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

    2016-01-01

    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

  3. Engineering and Preclinical Evaluation of Attenuated Nontyphoidal Salmonella Strains Serving as Live Oral Vaccines and as Reagent Strains▿†

    OpenAIRE

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

    2011-01-01

    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...

  4. Is a single dose of meningococcal serogroup C conjugate vaccine sufficient for protection? experience from the Netherlands

    Directory of Open Access Journals (Sweden)

    Kaaijk Patricia

    2012-02-01

    Full Text Available Abstract Background The first meningococcal serogroup C (MenC conjugate vaccine was licensed in 1999 and introduced in the United Kingdom. Countries that have implemented the MenC vaccine since then in their national immunisation programmes use different schedules. Nevertheless, all involved countries seem to experience substantial declines in the incidence of MenC disease. Discussion Since 2001, the MenC conjugate vaccine has been implemented in the Netherlands by offering a single dose to all children aged 14 months. Prior to the introduction of the vaccine into the national immunisation programme, a catch-up vaccination campaign was initiated in which a single dose of the MenC conjugate vaccine was offered to all children aged from 14 months up to and including 18 years. Since then, there has been no report of any case of MenC disease among immunocompetent vaccinees. Administration of a single dose of MenC conjugate vaccine after infancy could be beneficial considering the already complex immunisation schedules with large numbers of vaccinations in the first year of life. The present paper deals with the advantages and critical aspects of a single dose of the MenC conjugate vaccine. Summary A single dose of MenC conjugate vaccine at the age of 14 months in combination with a catch up vaccine campaign appeared to be a successful strategy to prevent MenC disease in the Netherlands, thereby confirming that a single dose of the vaccine could sufficiently protect against disease. Nevertheless, this approach can only be justified in countries with a relatively low incidence of serogroup C meningococcal disease in the first year of life. Furthermore, a good surveillance programme is recommended for timely detection of vaccine breakthroughs and outbreaks among non-vaccinees, since long-term protection after a single dose in the second year of life cannot currently be guaranteed.

  5. 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

  6. Comparison of the efficacy of Brucella abortus strain RB51 and Brucella melitensis Rev. 1 live vaccines against experimental infection with Brucella melitensis in pregnant ewes.

    Science.gov (United States)

    el Idrissi, A H; Benkirane, A; el Maadoudi, M; Bouslikhane, M; Berrada, J; Zerouali, A

    2001-12-01

    To test the efficacy of rough Brucella strain vaccines in sheep, a vaccine recently developed in cattle (Brucella abortus strain RB51) was assessed in comparison with the conventional Rev. 1 vaccine. Forty-five ewes from twelve to fourteen months of age, from brucellosis-free flocks, were allotted to three groups of fifteen ewes each. Group one was vaccinated by the conjunctival route with 1.73 x 10(8) colony forming units (CFU) of Rev. 1 vaccine. Group two was vaccinated subcutaneously with 11 x 10(9) CFU of RB51 vaccine and group three was considered as a control. All sheep were challenged at two to three months of gestation with 5 x 10(7) CFU of virulent B. melitensis H38. Vaccination with RB51 vaccine did not result in the production of any antibodies against the O-side chain of lipopolysaccharide, as measured by conventional serological tests (Rose Bengal plate test and complement fixation test). Protection of sheep against abortion and excretion of virulent Brucella strain in vaginal fluid, aborted foetuses and/or non viable lambs at parturition and abortion was significantly lower than that afforded by Rev. 1 vaccine. The difference compared to the control group was not significant. Data from this study suggest that the RB51 vaccine used for cattle vaccination does not provide effective protection of sheep against abortion induced by B. melitensis.

  7. A trivalent virus-like particle vaccine elicits protective immune responses against seasonal influenza strains in mice and ferrets.

    Directory of Open Access Journals (Sweden)

    Ted M Ross

    Full Text Available There is need for improved human influenza vaccines, particularly for older adults who are at greatest risk for severe disease, as well as to address the continuous antigenic drift within circulating human subtypes of influenza virus. We have engineered an influenza virus-like particle (VLP as a new generation vaccine candidate purified from the supernatants of Sf9 insect cells following infection by recombinant baculoviruses to express three influenza virus proteins, hemagglutinin (HA, neuraminidase (NA, and matrix 1 (M1. In this study, a seasonal trivalent VLP vaccine (TVV formulation, composed of influenza A H1N1 and H3N2 and influenza B VLPs, was evaluated in mice and ferrets for the ability to elicit antigen-specific immune responses. Animals vaccinated with the TVV formulation had hemagglutination-inhibition (HAI antibody titers against all three homologous influenza virus strains, as well as HAI antibodies against a panel of heterologous influenza viruses. HAI titers elicited by the TVV were statistically similar to HAI titers elicited in animals vaccinated with the corresponding monovalent VLP. Mice vaccinated with the TVV had higher level of influenza specific CD8+ T cell responses than a commercial trivalent inactivated vaccine (TIV. Ferrets vaccinated with the highest dose of the VLP vaccine and then challenged with the homologous H3N2 virus had the lowest titers of replicating virus in nasal washes and showed no signs of disease. Overall, a trivalent VLP vaccine elicits a broad array of immunity and can protect against influenza virus challenge.

  8. The vaccination of human beings with a live avirulent strain of Trypanosoma cruzi: a new series of volunteers

    Directory of Open Access Journals (Sweden)

    Humberto Menezes

    1973-04-01

    Full Text Available Five human volunteers were vaccinated with a live avirulent strain of Trypanosoma cruzi and followed-up for one year. Except for a few cases of questionable results presented by only one Laboratory, ali the other clinicai, parasitological and serological tests remained negative during that period.

  9. Brucella abortus strain RB51 leucine auxotroph as an environmentally safe vaccine for plasmid maintenance and antigen overexpression.

    Science.gov (United States)

    Rajasekaran, Parthiban; Seleem, Mohamed N; Contreras, Andrea; Purwantini, Endang; Schurig, Gerhardt G; Sriranganathan, Nammalwar; Boyle, Stephen M

    2008-11-01

    To avoid potentiating the spread of an antibiotic resistance marker, a plasmid expressing a leuB gene and a heterologous antigen, green fluorescent protein (GFP), was shown to complement a leucine auxotroph of cattle vaccine strain Brucella abortus RB51, which protected CD1 mice from virulent B. abortus 2308 and elicited GFP antibodies.

  10. 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....

  11. 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.

  12. 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

  13. 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

  14. An ELISA for the evaluation of gamma interferon production in cattle vaccinated with Brucella abortus strain RB51.

    Science.gov (United States)

    Tittarelli, Manuela; De Massis, Fabrizio; Bonfini, Barbara; Di Ventura, Mauro; Scacchia, Massimo

    2009-01-01

    The results of an enzyme-linked immunosorbent assay (ELISA) implemented for the detection of gamma interferon (gamma interferon) production in cattle vaccinated with Brucella abortus strain RB51 are presented. A purified protein fraction derived from RB51 (RB51 brucellin) has been used as antigenic stimulus for whole blood. The test was evaluated for 300 days in ten heifers vaccinated at calfhood with 10 x 10(9) colony-forming units of RB51 and in five control heifers. All animals came from officially brucellosis-free herds. Vaccinated animals started to give positive results from day 17 post vaccination (pv) until day 239 pv. All vaccinated animals gave a positive reaction at least once (with a stimulation index exceeding 2.5). Nevertheless, if sampling on day 20 pv is excluded (90% of vaccinated animals gave positive results), the sensitivity of the test varies from 20% to 70%, with a 40% average. A stimulation index over 2.5 was also recorded in three control animals. The results suggest that the gamma-interferon test is not suitable for the detection of cattle vaccinated with RB51, either at the individual or at the herd level.

  15. An ELISA for the evaluation of gamma interferon production in cattle vaccinated with Brucella abortus strain RB51

    Directory of Open Access Journals (Sweden)

    Manuela Tittarelli

    2009-06-01

    Full Text Available The results of an enzyme-linked immunosorbent assay (ELISA implemented for the detection of gamma interferon (g-interferon production in cattle vaccinated with Brucella abortus strain RB51 are presented. A purified protein fraction derived from RB51 (RB51 brucellin has been used as antigenic stimulus for whole blood. The test was evaluated for 300 days in ten heifers vaccinated at calfhood with 10 × 109 colony-forming units of RB51 and in five control heifers. All animals came from officially brucellosis-free herds. Vaccinated animals started to give positive results from day 17 post vaccination (pv until day 239 pv. All vaccinated animals gave a positive reaction at least once (with a stimulation index exceeding 2.5. Nevertheless, if sampling on day 20 pv is excluded (90% of vaccinated animals gave positive results, the sensitivity of the test varies from 20% to 70%, with a 40% average. A stimulation index over 2.5 was also recorded in three control animals. The results suggest that the g-interferon test is not suitable for the detection of cattle vaccinated with RB51, either at the individual or at the herd level.

  16. Efficacy of single dose of a bivalent vaccine containing inactivated Newcastle disease virus and reassortant highly pathogenic avian influenza H5N1 virus against lethal HPAI and NDV infection in chickens.

    Directory of Open Access Journals (Sweden)

    Dong-Hun Lee

    Full Text Available Highly pathogenic avian influenza (HPAI and Newcastle disease (ND are 2 devastating diseases of poultry, which cause great economic losses to the poultry industry. In the present study, we developed a bivalent vaccine containing antigens of inactivated ND and reassortant HPAI H5N1 viruses as a candidate poultry vaccine, and we evaluated its immunogenicity and protective efficacy in specific pathogen-free chickens. The 6:2 reassortant H5N1 vaccine strain containing the surface genes of the A/Chicken/Korea/ES/2003(H5N1 virus was successfully generated by reverse genetics. A polybasic cleavage site of the hemagglutinin segment was replaced by a monobasic cleavage site. We characterized the reverse genetics-derived reassortant HPAI H5N1 clade 2.5 vaccine strain by evaluating its growth kinetics in eggs, minimum effective dose in chickens, and cross-clade immunogenicity against HPAI clade 1 and 2. The bivalent vaccine was prepared by emulsifying inactivated ND (La Sota strain and reassortant HPAI viruses with Montanide ISA 70 adjuvant. A single immunization with this vaccine induced high levels of hemagglutination-inhibiting antibody titers and protected chickens against a lethal challenge with the wild-type HPAI and ND viruses. Our results demonstrate that the bivalent, inactivated vaccine developed in this study is a promising approach for the control of both HPAI H5N1 and ND viral infections.

  17. Characterization of Recombinant B. abortus Strain RB51SOD Toward Understanding the Uncorrelated Innate and Adaptive Immune Responses Induced by RB51SOD Compared to Its Parent Vaccine Strain RB51

    OpenAIRE

    Zhu, Jianguo; Larson, Charles B.; Ramaker, Megan Ann; Quandt, Kimberly; Wendte, Jered M.; Ku, Kimberly P.; Chen, Fang; Jourdian, George W.; Vemulapalli, Ramesh; Schurig, Gerhardt G.; He, Yongqun

    2011-01-01

    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. ...

  18. 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

    OpenAIRE

    Jianguo eZhu; Jianguo eZhu; Charles Bradford Larson; Megan Ann Ramaker; Kimberly eQuandt; Jered eWendte; Kimberly eKu; Fang eChen; George eJourdian; Ramesh eVemulapalli; Gerhardt G. Schurig; Yongqun Oliver eHe

    2011-01-01

    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. ...

  19. 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.

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

    Science.gov (United States)

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

    2015-01-15

    The aim of the present study was to evaluate the use of different mouse strains (BALB/c, Swiss and CD-1) and different challenge strains (Brucella abortus 544 and 2308) in the study of B. abortus vaccine (S19 and RB51) immunogenicity test in the murine model. No significant difference in B. abortus vaccine potency assay was found with the use of B. abortus 544 or B. abortus 2308 as challenge strain. Results of variance analysis showed an interaction between treatment and mouse strain; therefore these parameters could not be compared separately. When CD-1 groups were compared, those vaccinated showed significantly lower counts than non-vaccinated ones (PRB51). Similar results were observed on BALB/c groups. However, in Swiss mouse groups, S19 was more protective than RB51 (PRB51 vaccines. Copyright © 2014 Elsevier Ltd. All rights reserved.

  1. Challenge of pigs with classical swine fever viruses after C-strain vaccination reveals remarkably rapid protection and insights into early immunity.

    Science.gov (United States)

    Graham, Simon P; Everett, Helen E; Haines, Felicity J; Johns, Helen L; Sosan, Olubukola A; Salguero, Francisco J; Clifford, Derek J; Steinbach, Falko; Drew, Trevor W; Crooke, Helen R

    2012-01-01

    Pre-emptive culling is becoming increasingly questioned as a means of controlling animal diseases, including classical swine fever (CSF). This has prompted discussions on the use of emergency vaccination to control future CSF outbreaks in domestic pigs. Despite a long history of safe use in endemic areas, there is a paucity of data on aspects important to emergency strategies, such as how rapidly CSFV vaccines would protect against transmission, and if this protection is equivalent for all viral genotypes, including highly divergent genotype 3 strains. To evaluate these questions, pigs were vaccinated with the Riemser® C-strain vaccine at 1, 3 and 5 days prior to challenge with genotype 2.1 and 3.3 challenge strains. The vaccine provided equivalent protection against clinical disease caused by for the two challenge strains and, as expected, protection was complete at 5 days post-vaccination. Substantial protection was achieved after 3 days, which was sufficient to prevent transmission of the 3.3 strain to animals in direct contact. Even by one day post-vaccination approximately half the animals were partially protected, and were able to control the infection, indicating that a reduction of the infectious potential is achieved very rapidly after vaccination. There was a close temporal correlation between T cell IFN-γ responses and protection. Interestingly, compared to responses of animals challenged 5 days after vaccination, challenge of animals 3 or 1 days post-vaccination resulted in impaired vaccine-induced T cell responses. This, together with the failure to detect a T cell IFN-γ response in unprotected and unvaccinated animals, indicates that virulent CSFV can inhibit the potent antiviral host defences primed by C-strain in the early period post vaccination.

  2. Challenge of pigs with classical swine fever viruses after C-strain vaccination reveals remarkably rapid protection and insights into early immunity.

    Directory of Open Access Journals (Sweden)

    Simon P Graham

    Full Text Available Pre-emptive culling is becoming increasingly questioned as a means of controlling animal diseases, including classical swine fever (CSF. This has prompted discussions on the use of emergency vaccination to control future CSF outbreaks in domestic pigs. Despite a long history of safe use in endemic areas, there is a paucity of data on aspects important to emergency strategies, such as how rapidly CSFV vaccines would protect against transmission, and if this protection is equivalent for all viral genotypes, including highly divergent genotype 3 strains. To evaluate these questions, pigs were vaccinated with the Riemser® C-strain vaccine at 1, 3 and 5 days prior to challenge with genotype 2.1 and 3.3 challenge strains. The vaccine provided equivalent protection against clinical disease caused by for the two challenge strains and, as expected, protection was complete at 5 days post-vaccination. Substantial protection was achieved after 3 days, which was sufficient to prevent transmission of the 3.3 strain to animals in direct contact. Even by one day post-vaccination approximately half the animals were partially protected, and were able to control the infection, indicating that a reduction of the infectious potential is achieved very rapidly after vaccination. There was a close temporal correlation between T cell IFN-γ responses and protection. Interestingly, compared to responses of animals challenged 5 days after vaccination, challenge of animals 3 or 1 days post-vaccination resulted in impaired vaccine-induced T cell responses. This, together with the failure to detect a T cell IFN-γ response in unprotected and unvaccinated animals, indicates that virulent CSFV can inhibit the potent antiviral host defences primed by C-strain in the early period post vaccination.

  3. 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

  4. 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)

  5. 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.

  6. Construction of Opa-positive and Opa-negative strains of Neisseria meningitidis to evaluate a novel meningococcal vaccine.

    Science.gov (United States)

    Sadarangani, Manish; Hoe, J Claire; Callaghan, Martin J; Jones, Claire; Chan, Hannah; Makepeace, Katherine; Daniels-Treffandier, Hélène; Deadman, Mary E; Bayliss, Christopher; Feavers, Ian; van der Ley, Peter; Pollard, Andrew J

    2012-01-01

    Neisseria meningitidis is a major global pathogen causing invasive disease with a mortality of 5-10%. Most disease in developed countries is caused by serogroup B infection, against which there is no universal vaccine. Opacity-associated adhesin (Opa) proteins are major meningococcal outer membrane proteins, which have shown recent promise as a potential novel vaccine. Immunisation of mice with different Opa variants elicited high levels of meningococcal-specific bactericidal antibodies, demonstrating proof in principle for this approach. Opa proteins are critical in meningococcal pathogenesis, mediating bacterial adherence to host cells, and modulating human cellular immunity via interactions with T cells and neutrophils, although there are conflicting data regarding their effects on CD4(+) T cells. We constructed Opa-positive and Opa-negative meningococcal strains to allow further evaluation of Opa as a vaccine component. All four opa genes from N. meningitidis strain H44/76 were sequentially disrupted to construct all possible combinations of N. meningitidis strains deficient in one, two, three, or all four opa genes. The transformations demonstrated that homologous recombination of exogenous DNA into the meningococcal chromosome can occur with as little as 80 bp, and that minor sequence differences are permissible. Anti-Opa bactericidal antibody responses following immunisation of mice with recombinant Opa were specific to the Opa variant used in immunisation. No immunomodulatory effects were observed when Opa was contained within meningococcal outer membrane vesicles (OMVs), compared to Opa-negative OMVs. These observations support the incorporation of Opa in meningococcal vaccines.

  7. 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)

  8. A hepatitis C virus (HCV) vaccine comprising envelope glycoproteins gpE1/gpE2 derived from a single isolate elicits broad cross-genotype neutralizing antibodies in humans

    DEFF Research Database (Denmark)

    Law, John Lok Man; Chen, Chao; Wong, Jason

    2013-01-01

    Although a cure for HCV is on the near horizon, emerging drug cocktails will be expensive, associated with side-effects and resistance making a global vaccine an urgent priority given the estimated high incidence of infection around the world. Due to the highly heterogeneous nature of HCV...... genotypes. Although observed in only a minority of vaccinees, our results prove the key concept that a vaccine derived from a single strain of HCV can elicit broad cross-neutralizing antibodies against all known major genotypes of HCV and provide considerable encouragement for the further development......, an effective HCV vaccine which could elicit broadly cross-neutralizing antibodies has represented a major challenge. In this study, we tested for the presence of cross-neutralizing antibodies in human volunteers who were immunized with recombinant glycoproteins gpE1/gpE2 derived from a single HCV strain (HCV1...

  9. Recombinant BCG: Innovations on an old vaccine. Scope of BCG strains and strategies to improve long lasting memory

    Directory of Open Access Journals (Sweden)

    Adeliane C da Costa

    2014-04-01

    Full Text Available BCG (Bacille Calmette-Guérin, an attenuated vaccine derived from Mycobacterium bovis, is the current vaccine of choice against tuberculosis (TB. Despite its protection against active TB in children, BCG has failed to protect adults against TB infection and active disease development, especially in developing countries where the disease is endemic. Currently, there is a significant effort towards the development of a new TB vaccine. This review article aims to address publications on recombinant BCG (rBCG published in the last 5 years, to highlight the strategies used to develop rBCG, with a focus on the criteria used to improve immunological memory and protection compared with BCG. The literature review was done in April 2013, using the key words tuberculosis, rBCG vaccine and memory. This review discusses the BCG strains and strategies currently used for the modification of BCG, including: overexpression of M. tuberculosis (Mtb immunodominant antigens already present in BCG; gene insertion of immunodominant antigens from Mtb absent in the BCG vaccine; combination of introduction and over expression of genes that are lost during the attenuation process of BCG; BCG modifications for the induction of CD8+ T cell immune responses and cytokines expressing rBCG. Among the vaccines discussed, VPM1002, also called rBCGΔureC::hly, is currently in human clinical trials. Much progress has been made in the effort to improve BCG, with some promising candidates, but considerable work is still required to address functional long-lasting memory.

  10. Equine influenza: evaluation of the humoral immune response through the hemagglutination inhibition and single radial haemolysis, in vaccinated horses with commercial and experimental vaccines

    Directory of Open Access Journals (Sweden)

    Dalva Assunção Portari Mancini

    1996-03-01

    Full Text Available Equine Influenza: evaluation of the humoral immune response through the hemagglutination inhibition and single radial haemolysis, in horses vaccinated with commercial and experimental vaccines. From 4 equine groups, the antibody protection levels against influenza were evaluted through the hemagglutination inhibition and single radial haemolysis. One group of these animals received immunization from 2 doses of influenza vaccine, of experimental preparation, at the Butantan Institute, São Paulo, Brasil (IB. Two other horse groups, regularly vaccinated received the annual booster dose from both commercial and experimental vaccines (IB. A control group remained without vaccination. Differences were observed among the antibody level medians of the serum samples harvested prior and post immunization of those vaccinated animals. No evident differences were detected among the antibody level medians from animals that received annual booster doses, due to the persistence of the protective antibody level, 12 months after the regular immunization. In the control group, the animals showed low antibody levels, for both serum samples. In fact these results suggested the good serologic response of both vaccines, the commercial and the experimental, tested preparations.

  11. Lumpy skin disease outbreaks in Greece during 2015-16, implementation of emergency immunization and genetic differentiation between field isolates and vaccine virus strains.

    Science.gov (United States)

    Agianniotaki, Eirini I; Tasioudi, Konstantia E; Chaintoutis, Serafeim C; Iliadou, Peristera; Mangana-Vougiouka, Olga; Kirtzalidou, Aikaterini; Alexandropoulos, Thomas; Sachpatzidis, Achilleas; Plevraki, Evangelia; Dovas, Chrysostomos I; Chondrokouki, Eleni

    2017-03-01

    The objective of this study is to present epizootiological data from the lumpy skin disease (LSD) outbreaks in Greece during 2015-16, following the implementation of emergency vaccination and total stamping-out, along with laboratory data regarding the genetic differentiation between field isolates and live attenuated vaccine virus strains. Descriptive geographical chronology analysis was conducted to present the progressive shift of the outbreaks westwards, and at the same time, the absence of further outbreaks in previously affected regional units where high vaccination coverage was achieved. Isolation and molecular characterization of LSDV from the first recorded case in Greece (Evros/GR/15 isolate) was performed. The two live attenuated LSD vaccine viruses, currently used for emergency immunization in Greece, were sequenced and compared to the Evros/GR/15 isolate, in 3 genomic regions (GPCR gene, RPO30 gene, and partial LSDV126/LSDV127 genes). Sequence comparisons revealed prominent differences between the Evros/GR/15 isolate and the vaccine strains. Phylogenetic analysis resulted in the classification of the Evros/GR/15 isolate in the same clade with all field LSDV isolates, whereas vaccine strains were grouped in a distinct cluster within the LSDV clade. Additional samples from animals presenting skin nodules (N=13) were characterized by sequencing in the 3 aforementioned genomic regions. Among them, in 5 animals that were vaccinated, the attenuated vaccine virus was identified. A PCR-RFLP method targeting the LSDV127 gene was developed and proved to be able to discriminate between the characterized field and vaccine strains. The findings of the present study substantiate the importance of timely and intensive vaccinations for the control of LSDV epizootic and the genetic differences between the Evros/GR/15 isolate and the vaccine strains. This provides the basis for the development of PCR-based DIVA assays, which would be of major importance for effective

  12. The MSHA strain of Pseudomonas aeruginosa activated TLR pathway and enhanced HIV-1 DNA vaccine immunoreactivity.

    Directory of Open Access Journals (Sweden)

    Jue Hou

    Full Text Available The mannose-sensitive hemagglutination pilus strain of Pseudomonas aeruginosa (PA-MSHA has been shown to trigger naïve immune responses through the activation of monocytes, macrophages, natural killer cells (NK cells and antigen presenting cells (APCs. Based on the hypothesis that PA-MSHA activates natural immunity through the Toll-like receptor (TLR pathway, we scanned several critical TLR pathway molecules in mouse splenocytes using high-throughput real-time QRT-PCR and co-stimulatory molecule in bone marrow-derived dendritic cells (BMDCs following in vitro stimulation by PA-MSHA. PA-MSHA enabled activation of the TLR pathway mediated by NF-κB and JNK signaling in splenocytes, and the co-stimulatory molecule CD86 was up-regulated in BMDCs. We then assessed the adjuvant effect of PA-MSHA for HIV-1 DNA vaccines. In comparison to DNA inoculation alone, co-inoculation with low dosage of PA-MSHA enhanced specific immunoreactivity against HIV-1 Env in both cellular and humoral responses, and promoted antibody avidity maturation. However, high doses of adjuvant resulted in an immunosuppressive effect; a two- or three-inoculation regimen yielded low antibody responses and the two-inoculation regimen exhibited only a slight cellular immunity response. To our knowledge, this is the first report demonstrating the utility of PA-MSHA as an adjuvant to a DNA vaccine. Further research is needed to investigate the exact mechanisms through which PA-MSHA achieves its adjuvant effects on innate immune responses, especially on dendritic cells.

  13. 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...

  14. Recombination in JXA1-R vaccine and NADC30-like strain of porcine reproductive and respiratory syndrome viruses.

    Science.gov (United States)

    Liu, Jiankui; Zhou, Xia; Zhai, Junqiong; Wei, Chunhua; Dai, Ailing; Yang, Xiaoyan; Luo, Manlin

    2017-05-01

    Porcine reproductive and respiratory syndrome (PRRS) is considered one of the most devastating swine diseases worldwide, resulting in immense economic losses. PRRS virus (PRRSV) has undergone rapid evolution since its first recognition in 1990s. In the present study, a PRRSV strain named FJXS15 causing high morbidity and mortality was isolated from piglets and sows from a farm participating in vaccination in China. Phylogenetic and molecular evolutionary analyses revealed that FJXS15 was highly similar to the JXA1-R vaccine strain (a live attenuated virus vaccine strain derived from the highly pathogenic PRRSV JXA1) in the ORF1a (nt 901-)-ORF4 (-nt 419) coding regions, as well as to FJZ03 (lineage 1, NADC30-like) in the 5'-UTR, ORF5a-ORF7 coding regions, and 3'-UTR, suggestive of a natural recombination event. Recombination analyses showed that recombination events occurred in two inter-lineage recombination events between Lineages 1 and 8 based on based on classification system (Shi et al., 2010), and two recombination breakpoints at positions 1-1092 and 13771-15537 of the sequence alignment (with reference to the VR-2332 strain). Animal experiments demonstrated that FJXS15-infected animals had more severe histopathological lung lesions than did JXA1-R-infected and control groups. A 25% mortality rate was found in FJXS15-infected piglets, which was similar to that found with other Chinese HP-PRRSV strains. Thus, the recombinant virus is a highly virulent PRRSV. Moreover, this report provides evidence for inter-subgenotypic recombination between the JXA1-R vaccine virus and a circulating Lineage 1 virus. Copyright © 2017. Published by Elsevier B.V.

  15. Effect of polymyxin B and environmental conditions on isolation of Brucella species and the vaccine strain RB51.

    Science.gov (United States)

    Jensen, Allen E; Halling, Shirley M

    2010-03-01

    Brucella are resistant to polymyxin B (PB), but their relative susceptibility to PB and its derivative, colistin (COL) has not been rigorously or systematically studied. Comparative susceptibility of Brucella reference strains, vaccine strain RB51, and Brucella isolates from marine mammals to these two cationic peptides were determined by Etest. Vast differences among Brucella species were found in susceptibility to both PB and COL. Brucella demonstrated similar pattern of relative susceptibility to PB as that of COL, but they were less susceptible to COL. Both B. melitensis and B. suis were the least susceptible to polymyxins and rough strains were more susceptible to both PB and COL than the smooth except for the BvrR mutant. Strains were generally less susceptible to PB when cultured in CO(2) rather than ambient air; some became more susceptible in acidified medium. Results show that environment cultural conditions must be considered when selecting for CO(2)-independent strains of Brucella especially the vaccine strain RB51 on selective media containing PB. Our observations extend basic knowledge of the differential resistance of Brucella to polymyxins. Published by Elsevier Ltd.

  16. Possible Impact of Yearly Childhood Vaccination With Trivalent Inactivated Influenza Vaccine (TIV) on the Immune Response to the Pandemic Strain H1N1.

    Science.gov (United States)

    Amer, Ahdi; Fischer, Howard; Li, Xiaoming; Asmar, Basim

    2016-03-01

    Annual vaccination of children against seasonal influenza with trivalent inactivated influenza vaccine (TIV) has shown to be beneficial. However, this yearly practice may have unintended effect. Studies have shown that infection with wild type influenza A viruses can stimulate protective heterotypic immunity against unrelated or new influenza subtypes. We hypothesized that a consequence of yearly TIV vaccination is lack of induction of heterotypic immunity against the recent H1N1 pandemic. This was a retrospective case-control study. We reviewed the medical records of polymerase chain reaction-confirmed cases of 2009 H1N1 influenza infection in children 6 months to 18 years and a matched control group seen during the pandemic. We identified 353 polymerase chain reaction-confirmed H1N1 cases and 396 matching control subjects. Among the H1N1 group, 202/353 (57%) cases received a total of 477 doses of seasonal TIV compared with 218/396 (55%) in the control group who received a total of 435 doses. Seasonal TIV uptake was significantly higher in the H1N1 group 477/548 (87%) than in the control group, 435/532 (81%) (P = .017). Seasonal TIV uptake was significantly higher in H1N1-infected group. The finding suggests that the practice of yearly vaccination with TIV might have negatively affected the immune response against the novel pandemic H1N1 strain. Given the rarity of pandemic novel influenza viruses, and the high predictability of seasonal influenza occurrence, the practice of yearly influenza vaccination should be continued. However, the use of live attenuated intranasal vaccine, as opposed to TIV, may allow for the desirable development of a vigorous heterotypic immune response against future pandemics. © The Author(s) 2015.

  17. Genetic stability of Brucella abortus S19 and RB51 vaccine strains by multiple locus variable number tandem repeat analysis (MLVA16).

    Science.gov (United States)

    Dorneles, Elaine Maria Seles; de Faria, Ana Paula Paiva; Pauletti, Rebeca Barbosa; Santana, Jordana Almeida; Caldeira, George Afonso Vítor; Heinemann, Marcos Bryan; Titze-de-Almeida, Ricardo; Lage, Andrey Pereira

    2013-10-01

    The aims of the present study were (i) to assess the in vitro genetic stability of S19 and RB51 Brucella abortus vaccines strains and (ii) to evaluate the ability of multiple-locus variable-number tandem repeat (VNTR) analysis (MLVA) as a tool to be used in the quality control of live vaccines against brucellosis. Sixty-three batches of commercial S19 (n=53) and RB51 (n=10) vaccines, produced between 2006 and 2009, were used in this study. S19 and RB51 vaccines were obtained from, respectively, seven and two different manufacturers. Ten in vitro serial passages were performed on reference strains and on selected batches of commercial vaccines. All batches, reference strains and strains of serial passages were typed by the MLVA16. The results demonstrated that B. abortus S19 and RB51 vaccine strains are genetically stable and very homogeneous in their respective groups. Anyway, batches of S19 from one manufacturer and batches of RB51 from another presented genotypes distincts from the reference vaccine strains. In both cases, differences were found on locus Bruce07, which had addition of one repeat unit in the case of S19 batches and the deletion of one repeat unit in the case of RB51 batches. In summary, MLVA16 proved to be a molecular tool capable of discriminating small genomic variations and should be included in in vitro official tests. Copyright © 2013. Published by Elsevier Ltd.

  18. Immunogenicity and protective efficacy of a single-dose live non-pathogenic Escherichia coli oral vaccine against F4-positive enterotoxigenic Escherichia coli challenge in pigs.

    Science.gov (United States)

    Fairbrother, John Morris; Nadeau, Éric; Bélanger, Louise; Tremblay, Cindy-Love; Tremblay, Danielle; Brunelle, Mélanie; Wolf, Regina; Hellmann, Klaus; Hidalgo, Álvaro

    2017-01-05

    Enterotoxigenic Escherichia coli strains expressing F4 (K88) fimbriae (F4-ETEC) are one of the most important causes of post-weaning diarrhea (PWD) in pigs. F4, a major antigen, plays an important role in the early steps of the infection. Herein, the efficacy of a live oral vaccine consisting of a non-pathogenic E. coli strain expressing F4 for protection of pigs against PWD was evaluated. Three blinded, placebo-controlled, block design, parallel-group confirmatory experiments were conducted, using an F4-ETEC PWD challenge model, each with a different vaccination-challenge interval (3, 7, and 21days). The pigs were vaccinated via the drinking water with a single dose of the Coliprotec® F4 vaccine one day post-weaning. Efficacy was assessed by evaluating diarrhea, clinical observations, intestinal fluid accumulation, weight gain, intestinal colonization and fecal shedding of F4-ETEC. The immune response was evaluated by measuring serum and intestinal F4-specific antibodies. The administration of the vaccine resulted in a significant reduction of the incidence of moderate to severe diarrhea, ileal colonization by F4-ETEC, and fecal shedding of F4-ETEC after the heterologous challenge at 7 and 21days post-vaccination. The 7-day onset of protection was associated with an increase of serum anti-F4 IgM whereas the 21-day duration of protection was associated with an increase of both serum anti-F4 IgM and IgA. Significant correlations between levels of serum and intestinal secretory anti-F4 antibodies were detected. Maternally derived F4-specific serum antibodies did not interfere with the vaccine efficacy. The evaluation of protection following a challenge three days after vaccination showed a reduction of the severity and the duration of diarrhea and of fecal shedding of F4-ETEC. The 7-day onset and the 21-day duration of protection induced by Coliprotec® F4 vaccine administered once in drinking water to pigs of at least 18days of age were confirmed by protection

  19. Mosaic vaccines elicit CD8+ T cell responses in monkeys that confer immune coverage of diverse HIV strains

    Energy Technology Data Exchange (ETDEWEB)

    Fischer, Will [Los Alamos National Laboratory; Korber, Bette [Los Alamos National Laboratory

    2009-01-01

    Creation of a successful HIV vaccine will require the development of a strategy to generate cellular immunity with sufficient cross-clade breadth to deal with the extreme genetic diversity of the virus. Polyvalent mosaic immunogens derived from in silica recombination of natural strains of HIV are designed to induce cellular immune responses that maximally cover the sequence diversity of circulating virus isolates. Immunization of rhesus monkeys with plasmid DNA and recombinant vaccinia virus vaccine constructs expressing either consensus immunogens or polyvalent mosaic immunogens elicited a CD4+ T lymphocyte-biased response with comparably broad epitope-specific total T lymphocyte specificities. However, immunization with the mosaic immunogens induced HIV-specific CD8+ T lymphocyte responses with markedly greater depth and breadth. Therefore, the use of polyvalent mosaic immunogens is a promising strategy for a global vaccine for HIV.

  20. Non-chromatographic preparation of a bacterially produced single-shot modular virus-like particle capsomere vaccine for avian influenza.

    Science.gov (United States)

    Wibowo, Nani; Wu, Yang; Fan, Yuanyuan; Meers, Joanne; Lua, Linda H L; Middelberg, Anton P J

    2015-11-04

    Highly pathogenic avian influenza (HPAI) causes significant economic loss, reduced food security and poses an ongoing pandemic threat. Poultry vaccination significantly decreases these problems and recognizes that the health of humans, animals and ecosystems are connected. Low-cost manufacture of poultry vaccine matched quickly to the ever-changing circulating strain is needed for effective vaccination. Here, we re-engineered the process to manufacture bacterially synthesized modular capsomere comprising influenza M2e, previously shown to confer complete protection in challenged mice, for application in poultry. Modular capsomere was prepared using a simplified non-chromatographic salting-out precipitation method and its immunogenicity tested in vivo in poultry. Modular capsomere crudely purified by precipitation (pCapM2e) contained more contaminants than equivalent product purified by chromatography (cCapM2e). Unadjuvanted pCapM2e containing 80 EU of endotoxin per dose was inferior to highly purified and adjuvanted cCapM2e (2 EU per dose). However, addition of adjuvant to pCapM2e resulting in high immunogenicity after only a single dose of vaccination, yet without any local adverse reaction. This finding suggests a strong synergy between adjuvant, antigen and contaminants, and the possible existence of a "Goldilocks" level of contaminants, where high immunogenicity and low reactogenicity can be obtained in a single-shot vaccination. The simplified process offers potential cost and speed advantages to address the needs in influenza poultry vaccination in low-cost veterinary markets. Copyright © 2015 Elsevier Ltd. All rights reserved.

  1. 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.

  2. 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

  3. 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...

  4. 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

  5. The acceptability of three vaccine injections given to infants during a single clinic visit in South Africa

    Directory of Open Access Journals (Sweden)

    Hanani Tabana

    2016-08-01

    Full Text Available Abstract Background The Expanded Programme on Immunisation (EPI has increased the number of antigens and injections administered at one visit. There are concerns that more injections at a single immunisation visit could decrease vaccination coverage. We assessed the acceptability and acceptance of three vaccine injections at a single immunisation visit by caregivers and vaccinators in South Africa. Methods A mixed methods exploratory study of caregivers and vaccinators at clinics in two provinces of South Africa was conducted. Quantitative and qualitative data were collected using questionnaires as well as observations of the administration of three-injection vaccination sessions. Results The sample comprised 229 caregivers and 98 vaccinators. Caregivers were satisfied with the vaccinators’ care (97 % and their infants receiving immunisation injections (93 %. However, many caregivers, (86 % also felt that three or more injections were excessive at one visit. Caregivers had limited knowledge of actual vaccines provided, and reasons for three injections. Although vaccinators recognised the importance of informing caregivers about vaccination, they only did this sometimes. Overall, acceptance of three injections was high, with 97 % of caregivers expressing willingness to bring their infant for three injections again in future visits despite concerns about the pain and discomfort that the infant experienced. Many (55 % vaccinators expressed concern about giving three injections in one immunisation visit. However, in 122 (95 % observed three-injection vaccination sessions, the vaccinators administered all required vaccinations for that visit. The remaining seven vaccinations were not completed because of vaccine stock-outs. Conclusions We found high acceptance by caregivers and vaccinators of three injections. Caregivers’ poor understanding of reasons for three injections resulted from limited information sharing by vaccinators for

  6. 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

  7. Single zymomonas mobilis strain for xylose and arabinose fermentation

    Science.gov (United States)

    Zhang, Min; Chou, Yat-Chen; Picataggio, Stephen K.; Finkelstein, Mark

    1998-01-01

    This invention relates to single microorganisms which normally do not ferment pentose sugars which are genetically altered to ferment the pentose sugars, xylose and arabinose, to produce ethanol, and a fermentation process utilizing the same. Examples include Zymomonas mobilis which has been transformed with a combination of E. coli genes for xylose isomerase, xylulokinase, L-arabinose isomerase, L-ribulokinase, L-ribulose 5-phosphate 4-epimerase, transaldolase and transketolase. Expression of added genes are under the control of Z. mobilis promoters. These newly created microorganisms are useful for fermenting glucose, xylose and arabinose, produced by hydrolysis of hemicellulose and cellulose or starch, to produce ethanol.

  8. Neighborhood-targeted and case-triggered use of a single dose of oral cholera vaccine in an urban setting: Feasibility and vaccine coverage.

    Science.gov (United States)

    Parker, Lucy A; Rumunu, John; Jamet, Christine; Kenyi, Yona; Lino, Richard Laku; Wamala, Joseph F; Mpairwe, Allan M; Muller, Vincent; Llosa, Augusto E; Uzzeni, Florent; Luquero, Francisco J; Ciglenecki, Iza; Azman, Andrew S

    2017-06-01

    In June 2015, a cholera outbreak was declared in Juba, South Sudan. In addition to standard outbreak control measures, oral cholera vaccine (OCV) was proposed. As sufficient doses to cover the at-risk population were unavailable, a campaign using half the standard dosing regimen (one-dose) targeted high-risk neighborhoods and groups including neighbors of suspected cases. Here we report the operational details of this first public health use of a single-dose regimen of OCV and illustrate the feasibility of conducting highly targeted vaccination campaigns in an urban area. Neighborhoods of the city were prioritized for vaccination based on cumulative attack rates, active transmission and local knowledge of known cholera risk factors. OCV was offered to all persons older than 12 months at 20 fixed sites and to select groups, including neighbors of cholera cases after the main campaign ('case-triggered' interventions), through mobile teams. Vaccination coverage was estimated by multi-stage surveys using spatial sampling techniques. 162,377 individuals received a single-dose of OCV in the targeted neighborhoods. In these neighborhoods vaccine coverage was 68.8% (95% Confidence Interval (CI), 64.0-73.7) and was highest among children ages 5-14 years (90.0%, 95% CI 85.7-94.3), with adult men being less likely to be vaccinated than adult women (Relative Risk 0.81, 95% CI: 0.68-0.96). In the case-triggered interventions, each lasting 1-2 days, coverage varied (range: 30-87%) with an average of 51.0% (95% CI 41.7-60.3). Vaccine supply constraints and the complex realities where cholera outbreaks occur may warrant the use of flexible alternative vaccination strategies, including highly-targeted vaccination campaigns and single-dose regimens. We showed that such campaigns are feasible. Additional work is needed to understand how and when to use different strategies to best protect populations against epidemic cholera.

  9. Engineering Enhanced Vaccine Cell Lines To Eradicate Vaccine-Preventable Diseases: the Polio End Game

    OpenAIRE

    van der Sanden, Sabine M. G.; Wu, Weilin; Dybdahl-Sissoko, Naomi; Weldon, William C.; Brooks, Paula; O'Donnell, Jason; Jones, Les P.; Brown, Cedric; Tompkins, S. Mark; Oberste, M. Steven; Karpilow, Jon; Tripp, Ralph A.

    2016-01-01

    Vaccine manufacturing costs prevent a significant portion of the world's population from accessing protection from vaccine-preventable diseases. To enhance vaccine production at reduced costs, a genome-wide RNA interference (RNAi) screen was performed to identify gene knockdown events that enhanced poliovirus replication. Primary screen hits were validated in a Vero vaccine manufacturing cell line using attenuated and wild-type poliovirus strains. Multiple single and dual gene silencing event...

  10. Molecular cloning of Clostridium septicum vaccine strain alpha toxin gene in E. coli

    Directory of Open Access Journals (Sweden)

    Bozorgkhoo

    2014-05-01

    Full Text Available Clostridium septicum a Gram positive anaerobic bacterium produces several toxins including alpha, beta, gamma and delta. C. septicum alpha toxin is lethal and is responsible for a serious disease known as gas gangrene. The aim of the present study was to molecular cloning and sequencing of C. septicum vaccine strain alpha toxin gene. Genomic DNA was extracted using standard phenol and chloroform extraction method, and the target gene was amplified through PCR by specific primers. Quality and quantity of PCR product was evaluated using agarose gel electrophoresis and confirmed with spectrophotometry. The PCR product was purified and was ligated in pJET1.2blunt cloning vector and was used for E. coli/TOP10 competent cells transformation. pJETαsep recombinant plasmid was purified and sequenced using universal primers. Sequencing and BLAST analysis of csa showed over 99% identity to other previously deposited csa in the GenBank. The csa sequence was deposited in the GenBank under accession number JN793989. E. coli/TOP10/pJETαsep as a recombinant bacterium could be used for purifying of recombinant csa gene and its expression in the suitable prokaryotic hosts.

  11. 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.

  12. Comparison of microarray-predicted closest genomes to sequencing for poliovirus vaccine strain similarity and influenza A phylogeny.

    Science.gov (United States)

    Maurer-Stroh, Sebastian; Lee, Charlie W H; Patel, Champa; Lucero, Marilla; Nohynek, Hanna; Sung, Wing-Kin; Murad, Chrysanti; Ma, Jianmin; Hibberd, Martin L; Wong, Christopher W; Simões, Eric A F

    2016-03-01

    We evaluate sequence data from the PathChip high-density hybridization array for epidemiological interpretation of detected pathogens. For influenza A, we derive similar relative outbreak clustering in phylogenetic trees from PathChip-derived compared to classical Sanger-derived sequences. For a positive polio detection, recent infection could be excluded based on vaccine strain similarity. Copyright © 2016 The Authors. Published by Elsevier Inc. All rights reserved.

  13. Adapting to the global shortage of cholera vaccines: targeted single dose cholera vaccine in response to an outbreak in South Sudan.

    Science.gov (United States)

    Parker, Lucy A; Rumunu, John; Jamet, Christine; Kenyi, Yona; Lino, Richard Laku; Wamala, Joseph F; Mpairwe, Allan M; Ciglenecki, Iza; Luquero, Francisco J; Azman, Andrew S; Cabrol, Jean-Clement

    2017-04-01

    Shortages of vaccines for epidemic diseases, such as cholera, meningitis, and yellow fever, have become common over the past decade, hampering efforts to control outbreaks through mass reactive vaccination campaigns. Additionally, various epidemiological, political, and logistical challenges, which are poorly documented in the literature, often lead to delays in reactive campaigns, ultimately reducing the effect of vaccination. In June 2015, a cholera outbreak occurred in Juba, South Sudan, and because of the global shortage of oral cholera vaccine, authorities were unable to secure sufficient doses to vaccinate the entire at-risk population-approximately 1 million people. In this Personal View, we document the first public health use of a reduced, single-dose regimen of oral cholera vaccine, and show the details of the decision-making process and timeline. We also make recommendations to help improve reactive vaccination campaigns against cholera, and discuss the importance of new and flexible context-specific dose regimens and vaccination strategies. Copyright © 2017 Elsevier Ltd. All rights reserved.

  14. 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

  15. 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.

  16. Evidence for single-dose protection by the bivalent HPV vaccine-Review of the Costa Rica HPV vaccine trial and future research studies.

    Science.gov (United States)

    Kreimer, Aimée R; Herrero, Rolando; Sampson, Joshua N; Porras, Carolina; Lowy, Douglas R; Schiller, John T; Schiffman, Mark; Rodriguez, Ana Cecilia; Chanock, Stephen; Jimenez, Silvia; Schussler, John; Gail, Mitchell H; Safaeian, Mahboobeh; Kemp, Troy J; Cortes, Bernal; Pinto, Ligia A; Hildesheim, Allan; Gonzalez, Paula

    2018-01-20

    The Costa Rica Vaccine Trial (CVT), a phase III randomized clinical trial, provided the initial data that one dose of the HPV vaccine could provide durable protection against HPV infection. Although the study design was to administer all participants three doses of HPV or control vaccine, 20% of women did not receive the three-dose regimens, mostly due to involuntary reasons unrelated to vaccination. In 2011, we reported that a single dose of the bivalent HPV vaccine could be as efficacious as three doses of the vaccine using the endpoint of persistent HPV infection accumulated over the first four years of the trial; findings independently confirmed in the GSK-sponsored PATRICIA trial. Antibody levels after one dose, although lower than levels elicited by three doses, were 9-times higher than levels elicited by natural infection. Importantly, levels remained essentially constant over at least seven years, suggesting that the observed protection provided by a single dose might be durable. Much work has been done to assure these non-randomized findings are valid. Yet, the group of recipients who received one dose of the bivalent HPV vaccine in the CVT and PATRICIA trials was small and not randomly selected nor blinded to the number of doses received. The next phase of research is to conduct a formal randomized, controlled trial to evaluate the protection afforded by a single dose of HPV vaccine. Complementary studies are in progress to bridge our findings to other populations, and to further document the long-term durability of antibody response following a single dose. Published by Elsevier Ltd.

  17. Use of the complement fixation and brucellin skin tests to identify cattle vaccinated with Brucella abortus strain RB51.

    Science.gov (United States)

    De Massis, F; Giovannini, A; Di Emidio, B; Ronchi, G F; Tittarelli, M; Di Giannatale, E; Di Ventura, M; Nannini, D; Caporale, V

    2005-01-01

    In the European Union, RB51 vaccine can be used only under strictly controlled conditions for the immunisation of cattle at risk of infection with Brucella abortus. A test is therefore necessary to distinguish vaccinated from unvaccinated animals. The complement fixation test with RB51 antigen (RB51-CFT), dot-blot and gamma-interferon used to identify vaccinated animals have been described, but sensitivity of the tests has been poor and positivity transient after calfhood vaccination. To avail of a rapid and accurate diagnostic tool, the authors produced, controlled and evaluated an experimental brucellin prepared from strain RB51 (RB51 brucellin). The potency of this brucellin was evaluated in guinea-pigs sensitised with RB51 and compared with a commercially available brucellin. Both allergens produced similar biological activity in guinea-pigs. The RB51 brucellin skin test was performed in 10 cattle 414 days after calfhood vaccination with RB51 when they were negative to the RB51-CFT. The skin test revealed 60% sensitivity (with a confidence interval of 95%, CI 30.8%-83.3%) and 100% specificity (CI 60.7%-100%). These findings limit the use of the skin test only for screening to detect RB51 vaccinated herds, not individual animals. Nevertheless, following intradermal inoculation of RB51 brucellin, a transient antibody increase to the RB51-CFT was observed, from day 9 to day 20 post inoculation with RB51 brucellin. This transient antibody increase, when evaluated in parallel with the RB51 brucellin skin test results, enables detection of individual vaccinated animals (sensitivity 100%; CI 76.2%-100%).

  18. A rapid ELISA-based method for screening Bordetella pertussis strain production of antigens included in current acellular pertussis vaccines.

    Science.gov (United States)

    Barkoff, Alex-Mikael; Guiso, Nicole; Guillot, Sophie; Xing, Dorothy; Markey, Kevin; Berbers, Guy; Mertsola, Jussi; He, Qiushui

    2014-06-01

    Despite extensive vaccinations, there have been pertussis epidemics in many countries including the Netherlands, the UK, Australia and the USA. During these epidemics Bordetella pertussis strains not producing the vaccine antigen pertactin (Prn) are emerging and increasing in numbers. However, methods for confirming PRN production of B. pertussis isolates are combined PCR or PCR-based sequencing tests and western blotting. Furthermore, data about production of pertussis toxin (PT) and filamentous hemagglutinin (FHA) of these isolates are scarce. Fimbriae (Fim) production is usually determined by agglutination and reported as serotype. In this study we developed an easy, accurate and rapid method for screening PT and FHA production. Methods for Prn and Fim production have been published earlier. We analyzed altogether 109 B. pertussis strains, including 103 Finnish B. pertussis strains collected during 2006-2013, international strain Tohama I, French strains FR3496 (PT-negative), FR3693 (Prn-negative) and FR4624 (FHA-negative) and Fim-serotype reference strains S1 (producing only Fim2) and S3 (producing only Fim3). An indirect ELISA with whole bacterial cells as coating antigen was developed and used for rapid screening of the B. pertussis strains. Production of different antigens (PT, FHA, Prn, Fim2 and Fim3) was detected with specific monoclonal antibodies (mAbs). From the 103 Finnish B. pertussis strains tested, all were positive for PT, FHA and Fim. Four were found negative for Prn, and they were isolated during 2011-2013. The newly developed method proved to be useful and simple for rapid screening of different antigen production of B. pertussis isolates. Copyright © 2014 Elsevier B.V. All rights reserved.

  19. Genetic Determinants of Japanese Encephalitis Virus Vaccine Strain SA14-14-2 That Govern Attenuation of Virulence in Mice.

    Science.gov (United States)

    Gromowski, Gregory D; Firestone, Cai-Yen; Whitehead, Stephen S

    2015-06-01

    The safety and efficacy of the live-attenuated Japanese encephalitis virus (JEV) SA14-14-2 vaccine are attributed to mutations that accumulated in the viral genome during its derivation. However, little is known about the contribution that is made by most of these mutations to virulence attenuation and vaccine immunogenicity. Here, we generated recombinant JEV (rJEV) strains containing JEV SA14-14-2 vaccine-specific mutations that are located in the untranslated regions (UTRs) and seven protein genes or are introduced from PCR-amplified regions of the JEV SA14-14-2 genome. The resulting mutant viruses were evaluated in tissue culture and in mice. The authentic JEV SA14-14-2 (E) protein, with amino acid substitutions L107F, E138K, I176V, T177A, E244G, Q264H, K279M, A315V, S366A, and K439R relative to the wild-type rJEV clone, was essential and sufficient for complete attenuation of neurovirulence. Individually, the nucleotide substitution T39A in the 5' UTR (5'-UTR-T39A), the capsid (C) protein amino acid substitution L66S (C-L66S), and the complete NS1/2A genome region containing 10 mutations each significantly reduced virus neuroinvasion but not neurovirulence. The levels of peripheral virulence attenuation imposed by the 5'-UTR-T39A and C-L66S mutations, individually, were somewhat mitigated in combination with other vaccine strain-specific mutations, which might be compensatory, and together did not affect immunogenicity. However, a marked reduction in immunogenicity was observed with the addition of the NS1/2A and NS5 vaccine virus genome regions. These results suggest that a second-generation recombinant vaccine can be rationally engineered to maximize levels of immunogenicity without compromising safety. The live-attenuated JEV SA14-14-2 vaccine has been vital for controlling the incidence of disease caused by JEV, particularly in rural areas of Asia where it is endemic. The vaccine was developed >25 years ago by passaging wild-type JEV strain SA14 in tissue

  20. Cloning and expression of Clostridium perfringens type D vaccine strain epsilon toxin gene in E. coli as a recombinant vaccine candidate

    Science.gov (United States)

    Aziminia, Parastoo; Pilehchian-Langroudi, Reza; Esmaeilnia, Kasra

    2016-01-01

    Background and Objectives: Clostridium perfringens, a Gram-positive obligate anaerobic bacterium, is able to form resistant spores which are widely distributed in the environment. C. perfringens is subdivided into five types A to E based on its four major alpha, beta, epsilon and iota toxins. The aim of the present study was cloning and expression of C. perfringens type D vaccine strain epsilon toxin gene. Materials and Methods: Genomic DNA was extracted and the epsilon toxin gene was amplified using Pfu DNA polymerase. The PCR product was cloned into pJET1.2/blunt cloning vector. The recombinant vector (pJETε) was sequenced using universal primers. At the next step epsilon toxin gene was subcloned into pET22b(+) expression vector and transformed into E. coli Rosetta (DE3) host strain. Results: The recombinant protein has been expressed in E. coli Rosetta (DE3) cells after subcloning of C. perfringens etx gene (1008 bp) into the expression vector. Conclusion: We concluded that E. coli Rosetta strain was suitable for the expression of recombinant C. perfringens epsilon toxin protein from pET22ε expression vector. This recombinant cell can be used for further research on recombinant vaccine development. PMID:28210460

  1. Correlation between vaccine coverage against polio and circulation and genetic evolution of the poliovirus strains isolated in Romania in the framework of the global polio eradication strategy.

    Science.gov (United States)

    Băicuş, Anda; Persu, Ana; Popescu, Maria; Penciu, Alina; Stavri, Simona; Soare, Alina; Grecu, Nicolae; Szmal, Camelia; Oprişan, Gabriela

    2009-01-01

    Until 2008 in Romania poliomyelitis has been controlled by predominantly using trivalent oral poliovirus vaccine (TOPV). The alternative vaccination schedule (formalin inactivated poliovirus vaccine IPV/OPV) has been implemented starting September 2008 and at the begining of 2009 was decided only vaccination with IPV. Between 1995-2006 the risk of the vaccine-associated paralytic poliomyelitis (VAPP) decreased with an average of less than 2 VAPP cases/year and no VAPP case between 2007 - September 2009. Begining with 2007 the number of the poliovirus strains isolated was less. All 9 poliovirus strains (PV) isolated between 2007-2009 and investigated by RT-PCR-RFLP in VP1-2A and VP3-VP1 coding regions showed Sabin-like profiles, and only one strain poliovirus type 3 showed Sabin 2-like profile by RFLP in 3D coding ARN polymerase region. The study about the seroprevalence of antibodies against poliovirus types in serum samples from the acute flaccid paralysis (AFP), facial paralysis (FP) cases showed that the seroprevalence of antibodies against types 1 and 2 Sabin strains was higher (>90%) than for type 3 Sabin strains (average 85%). It was confirmed the necessity of maintaining a proper vaccine coverage in population, after the switch in the vaccination strategy in Romania until all threats of poliovirus are eliminated globally.

  2. Genetic Structure Change in Harvard Vaccine Strain of Clostridium Tetani for the Period of 1990 to 2010 by Pulsed-Field Gel Electrophoresis

    Directory of Open Access Journals (Sweden)

    Ahmad Sakhravi

    2013-07-01

    Full Text Available Background: PFGE facilitates the differential migration of large DNA fragments through agarose gel by constantly changing the direction of the electrical field during electrophoresis. Possibility of high difference between strains and repeatability make PFGE one of the strong molecular methods in study of bacterial strains in epidemiology. To identifying and DNA fingerprinting of vaccine strain of Clostridium tetani by PFGE technique. Also, possibility of genotyping profile changes in frequency of vaccine strain of C. tetani during the period of 1990 to 2011.Materials and Methods: The vaccine strain of C. tetani was provided by Razi Vaccine and Serum Research Institute in Karaj. The seeds were inoculated into Columbia blood agar and grown for 72 h. The cultures were incubated at 35°C in anaerobic conditions. The PFGE analyses were performed using genomic DNA digested with the restriction enzyme SmaI. The electrophoresis analyses were carried out on a CHEF DR III apparatus (Bio-Rad and band patterns obtained were then analyzed.Results: The PFGE profile obtained from vaccine strain during a period of more than two decades revealed no remarkable genetic changes and mutations. This type of analysis provides detailed data useful for surveillance of vaccine strains and isolates as well as for the selection of certain predominant profiles for further investigation.Conclusion: This study showed no considerable change in chromosomal genome of Harvard, the vaccine strain. It is therefore concluded that the vaccine produced by Razi Institute had evidently no alteration or modification in accordance to PFGE profile analysis during a period of more than two decades.

  3. Mobility-limiting mechanisms in single and dual channel strained Si/SiGe MOSFETs

    International Nuclear Information System (INIS)

    Olsen, S.H.; Dobrosz, P.; Escobedo-Cousin, E.; Bull, S.J.; O'Neill, A.G.

    2005-01-01

    Dual channel strained Si/SiGe CMOS architectures currently receive great attention due to maximum performance benefits being predicted for both n- and p-channel MOSFETs. Epitaxial growth of a compressively strained SiGe layer followed by tensile strained Si can create a high mobility buried hole channel and a high mobility surface electron channel on a single relaxed SiGe virtual substrate. However, dual channel n-MOSFETs fabricated using a high thermal budget exhibit compromised mobility enhancements compared with single channel devices, in which both electron and hole channels form in strained Si. This paper investigates the mobility-limiting mechanisms of dual channel structures. The first evidence of increased interface roughness due to the introduction of compressively strained SiGe below the tensile strained Si channel is presented. Interface corrugations degrade electron mobility in the strained Si. Roughness measurements have been carried out using AFM and TEM. Filtering AFM images allowed roughness at wavelengths pertinent to carrier transport to be studied and the results are in agreement with electrical data. Furthermore, the first comparison of strain measurements in the surface channels of single and dual channel architectures is presented. Raman spectroscopy has been used to study channel strain both before and after processing and indicates that there is no impact of the buried SiGe layer on surface macrostrain. The results provide further evidence that the improved performance of the single channel devices fabricated using a high thermal budget arises from improved surface roughness and reduced Ge diffusion into the Si channel

  4. Adaptive immune responses to booster vaccination against yellow fever virus are much reduced compared to those after primary vaccination

    DEFF Research Database (Denmark)

    Kongsgaard, Michael; Bassi, Maria R; Rasmussen, Michael

    2017-01-01

    Outbreaks of Yellow Fever occur regularly in endemic areas of Africa and South America frequently leading to mass vaccination campaigns straining the availability of the attenuated Yellow Fever vaccine, YF-17D. The WHO has recently decided to discontinue regular booster-vaccinations since a single...

  5. Mapping the "forbidden" transverse-optical phonon in single strained silicon (100) nanowire.

    Science.gov (United States)

    Tarun, Alvarado; Hayazawa, Norihiko; Ishitobi, Hidekazu; Kawata, Satoshi; Reiche, Manfred; Moutanabbir, Oussama

    2011-11-09

    The accurate manipulation of strain in silicon nanowires can unveil new fundamental properties and enable novel or enhanced functionalities. To exploit these potentialities, it is essential to overcome major challenges at the fabrication and characterization levels. With this perspective, we have investigated the strain behavior in nanowires fabricated by patterning and etching of 15 nm thick tensile strained silicon (100) membranes. To this end, we have developed a method to excite the "forbidden" transverse-optical (TO) phonons in single tensile strained silicon nanowires using high-resolution polarized Raman spectroscopy. Detecting this phonon is critical for precise analysis of strain in nanoscale systems. The intensity of the measured Raman spectra is analyzed based on three-dimensional field distribution of radial, azimuthal, and linear polarizations focused by a high numerical aperture lens. The effects of sample geometry on the sensitivity of TO measurement are addressed. A significantly higher sensitivity is demonstrated for nanowires as compared to thin layers. In-plane and out-of-plane strain profiles in single nanowires are obtained through the simultaneous probe of local TO and longitudinal-optical (LO) phonons. New insights into strained nanowires mechanical properties are inferred from the measured strain profiles.

  6. Interaction between single-dose Mycoplasma hyopneumoniae and porcine reproductive and respiratory syndrome virus vaccines on dually infected pigs.

    Science.gov (United States)

    Park, Su-Jin; Seo, Hwi Won; Park, Changhoon; Chae, Chanhee

    2014-06-01

    The objective of this study was to determine the effects of Mycoplasma hyopneumoniae and/or porcine reproductive and respiratory syndrome virus (PRRSV) vaccination on dually infected pigs. In total, 72 pigs were randomly divided into nine groups (eight pigs per group), as follows: five vaccinated and challenged groups, three non-vaccinated and challenged groups, and a negative control group. Single-dose vaccination against M. hyopneumoniae alone decreased the levels of PRRSV viremia and PRRSV-induced pulmonary lesions, whereas single-dose vaccination against PRRSV alone did not decrease nasal shedding of M. hyopneumoniae and mycoplasma-induced pulmonary lesions in the dually infected pigs. The M. hyopneumoniae challenge impaired the protective cell-mediated immunity induced by the PRRSV vaccine, whereas the PRRSV challenge did not impair the protective cell-mediated immunity induced by the M. hyopneumoniae vaccine. The present study provides swine practitioners and producers with efficient vaccination regimes; vaccination against M. hyopneumoniae is the first step in protecting pigs against co-infection with M. hyopneumoniae and PRRSV. Copyright © 2014 Elsevier Ltd. All rights reserved.

  7. Cell culture (Vero cell) derived whole-virus non-adjuvanted H5N1 influenza vaccine induces long-lasting cross-reactive memory immune response: homologous or heterologous booster response following two dose or single dose priming.

    Science.gov (United States)

    van der Velden, Maikel V W; Aichinger, Gerald; Pöllabauer, Eva Maria; Löw-Baselli, Alexandra; Fritsch, Sandor; Benamara, Karima; Kistner, Otfried; Müller, Markus; Zeitlinger, Markus; Kollaritsch, Herwig; Vesikari, Timo; Ehrlich, Hartmut J; Barrett, P Noel

    2012-09-21

    Influenza pandemic preparedness involves priming of the population with pre-pandemic vaccines. Such vaccines should be well tolerated and induce a long-lasting immunological memory that can effectively be boosted with a single dose of pandemic vaccine once available. The presented studies assessed different prime-boost regimens with a Vero cell-derived whole virus non-adjuvanted H5N1 vaccine. In one study, 281 healthy adult (18-59 years) and 280 elderly (≥ 60 years) subjects received two vaccinations, 21 days apart, with Vero cell-derived whole virus non-adjuvanted H5N1 vaccine (7.5 μg HA Antigen A/Vietnam/1203/2004) followed by a 6, 12-15, or 24 month booster (7.5 or 3.75μg A/Indonesia/05/2005 or A/Vietnam/1203/2004). In the other study, 230 healthy adults (18-59 years) received single dose priming (7.5 μg A/Vietnam/1203/2004) followed by a 12 month booster (7.5 or 3.75 μg A/Indonesia/05/2005). Antibody responses were assessed by microneutralization (MN) and single radial hemolysis (SRH) assay. Vaccine safety was assessed throughout. Two dose priming was equally immunogenic in adults and the elderly: >72% of subjects in each population achieved MN titers ≥ 1:20 after the second vaccination. Booster vaccinations at 6, 12-15, and 24 months induced substantial antibody increases to both strains: after a 7.5 μg A/Indonesia/05/2005 booster, 93-95% of adults and 72-84% of the elderly achieved MN titers ≥ 1:20 against this strain. Homologous and heterologous booster responses were higher in the 7.5μg dose group than in the 3.75 μg dose group. Booster responses following single dose priming were similar; a 7.5 μg booster dose induced homologous MN titers ≥ 1:20 in 93% of subjects. A Vero cell derived whole virus non-adjuvanted H5N1 influenza vaccine is well tolerated and induces long-lasting cross-clade immunological memory that can be effectively boosted 1-2 years after two dose or single dose priming, supporting its suitability for pre

  8. Detection and characterization of viruses as field and vaccine strains in feedlot cattle with bovine respiratory disease.

    Science.gov (United States)

    Fulton, R W; d'Offay, J M; Landis, C; Miles, D G; Smith, R A; Saliki, J T; Ridpath, J F; Confer, A W; Neill, J D; Eberle, R; Clement, T J; Chase, C C L; Burge, L J; Payton, M E

    2016-06-24

    This study investigated viruses in bovine respiratory disease (BRD) cases in feedlots, including bovine herpesvirus-1 (BoHV-1), bovine viral diarrhea virus (BVDV), bovine respiratory syncytial virus (BRSV), bovine coronaviruses (BoCV) and parainfluenza-3 virus (PI3V). Nasal swabs were collected from 114 cattle on initial BRD treatment. Processing included modified live virus (MLV) vaccination. Seven BRD necropsy cases were included for 121 total cases. Mean number of days on feed before first sample was 14.9 days. Swabs and tissue homogenates were tested by gel based PCR (G-PCR), quantitative-PCR (qPCR) and quantitative real time reverse transcriptase PCR (qRT-PCR) and viral culture. There were 87/114 (76.3%) swabs positive for at least one virus by at least one test. All necropsy cases were positive for at least one virus. Of 121 cases, positives included 18/121 (14.9%) BoHV-1; 19/121 (15.7%) BVDV; 76/121 (62.8%) BoCV; 11/121 (9.1%) BRSV; and 10/121 (8.3%) PI3V. For nasal swabs, G-PCR (5 viruses) detected 44/114 (38.6%); q-PCR and qRT-PCR (4 viruses) detected 81/114 (71.6%); and virus isolation detected 40/114 (35.1%). Most were positive for only one or two tests, but not all three tests. Necropsy cases had positives: 5/7 G-PCR, 5/7 q-PCR and qRT-PCR, and all were positive by cell culture. In some cases, G-PCR and both real time PCR were negative for BoHV-1, BVDV, and PI3V in samples positive by culture. PCR did not differentiate field from vaccines strains of BoHV-1, BVDV, and PI3V. However based on sequencing and analysis, field and vaccine strains of culture positive BoHV-1, BoCV, BVDV, and PI3V, 11/18 (61.1%) of BoHV-1 isolates, 6/17 (35.3%) BVDV isolates, and 1/10 (10.0%) PI3V identified as vaccine. BRSV was only identified by PCR testing. Interpretation of laboratory tests is appropriate as molecular based tests and virus isolation cannot separate field from vaccine strains. Additional testing using sequencing appears appropriate for identifying vaccine

  9. 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.

  10. 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

  11. Strain-hardening in nano-structured single phase steels: mechanisms and control.

    Science.gov (United States)

    Bouaziz, O; Barbier, D

    2012-11-01

    The detrimental effect of grain size refinement on the strain hardening is highlighted in single phase steels. A physical based approach for understanding the underlying mechanisms is presented. In order to overcome this limitation a promising metallurgical route exploiting the thermal stability of mechanically induced twins in austenitic steels has been successfully applied to a stainless grade confirming the opportunity to get nano-structured alloys exhibiting high yield stress with high strain-hardening.

  12. 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.

  13. Immune Responses and Protection against Experimental Challenge after Vaccination of Bison with Brucella abortus Strain RB51 or RB51 Overexpressing Superoxide Dismutase and Glycosyltransferase Genes▿

    OpenAIRE

    Olsen, S. C.; Boyle, S. M.; Schurig, G. G.; Sriranganathan, N. N.

    2009-01-01

    Vaccination is a tool that could be beneficial in managing the high prevalence of brucellosis in free-ranging bison in Yellowstone National Park. In this study, we characterized immunologic responses and protection against experimental challenge after vaccination of bison with Brucella abortus strain RB51 (RB51) or a recombinant RB51 strain overexpressing superoxide dismutase (sodC) and glycosyltransferase (wboA) genes (RB51+sodC,wboA). Bison were vaccinated with saline only or with 4.6 × 101...

  14. Remarkable similarity in genome nucleotide sequences between the Schwarz FF-8 and AIK-C measles virus vaccine strains and apparent nucleotide differences in the phosphoprotein gene.

    Science.gov (United States)

    Ito, Chie; Ohgimoto, Shinji; Kato, Seiichi; Sharma, Luna Bhatta; Ayata, Minoru; Komase, Katsuhiro; Takeuchi, Kaoru; Ihara, Toshiaki; Ogura, Hisashi

    2011-07-01

    The Schwarz FF-8 (FF-8) and AIK-C measles virus vaccine strains are currently used for vaccination in Japan. Here, the complete genome nucleotide sequence of the FF-8 strain has been determined and its genome sequence found to be remarkably similar to that of the AIK-C strain. These two strains are differentiated only by two nucleotide differences in the phosphoprotein gene. Since the FF-8 strain does not possess the amino acid substitutions in the phospho- and fusion proteins which are responsible for the temperature-sensitivity and small syncytium formation phenotypes of the AIK-C strain, respectively, other unidentified common mechanisms likely attenuate both the FF-8 and AIK-C strains. © 2011 The Societies and Blackwell Publishing Asia Pty Ltd.

  15. Recombinant BCG: Innovations on an Old Vaccine. Scope of BCG Strains and Strategies to Improve Long-Lasting Memory

    Science.gov (United States)

    da Costa, Adeliane Castro; Nogueira, Sarah Veloso; Kipnis, André; Junqueira-Kipnis, Ana Paula

    2014-01-01

    Bacille Calmette–Guérin (BCG), an attenuated vaccine derived from Mycobacterium bovis, is the current vaccine of choice against tuberculosis (TB). Despite its protection against active TB in children, BCG has failed to protect adults against TB infection and active disease development, especially in developing countries where the disease is endemic. Currently, there is a significant effort toward the development of a new TB vaccine. This review article aims to address publications on recombinant BCG (rBCG) published in the last 5 years, to highlight the strategies used to develop rBCG, with a focus on the criteria used to improve immunological memory and protection compared with BCG. The literature review was done in April 2013, using the key words TB, rBCG vaccine, and memory. This review discusses the BCG strains and strategies currently used for the modification of BCG, including: overexpression of Mycobacterium tuberculosis (Mtb) immunodominant antigens already present in BCG; gene insertion of immunodominant antigens from Mtb absent in the BCG vaccine; combination of introduction and overexpression of genes that are lost during the attenuation process of BCG; BCG modifications for the induction of CD8+ T-cell immune responses and cytokines expressing rBCG. Among the vaccines discussed, VPM1002, also called rBCGΔureC:hly, is currently in human clinical trials. Much progress has been made in the effort to improve BCG, with some promising candidates, but considerable work is still required to address functional long-lasting memory. PMID:24778634

  16. Pharmaceutical and immunological evaluation of a single-shot hepatitis B vaccine formulated with PLGA microspheres.

    Science.gov (United States)

    Shi, Li; Caulfield, Michael J; Chern, Rey T; Wilson, Roger A; Sanyal, Gautam; Volkin, David B

    2002-04-01

    A single-shot Hepatitis B vaccine formulation using poly(d,l)-lactide-co-glycolide acid (PLGA) microspheres as a delivery system was examined using a variety of biophysical and biochemical techniques as well as immunological evaluation in C3H mice. PLGA microsphere encapsulation of the Hepatitis B surface antigen (HBsAg), a lipoprotein particle, resulted in good recoveries of protein mass, protein particle conformational integrity, and in vitro antigenicity. Some partial delipidation of the HBsAg, however, was observed. The loading and encapsulation efficiency of HBsAg into the PLGA microspheres were measured along with the morphology and size distribution of the vaccine-loaded PLGA microspheres. The in vitro release kinetics of HBsAg from the PLGA microspheres was evaluated and found to be affected by experimental conditions such as stirring rate. HBsAg showed enhanced storage stability at 37 degrees C in the slightly acidic pH range reported to be found inside PLGA microspheres; thus, the antigen is relatively stable under conditions of temperature and pH that may mimic in vivo conditions. The immunogenicity of the microsphere formulations of HBsAg was compared with conventional aluminum adjuvant formulated HBsAg vaccine in C3H mice. Comparisons were made between aluminum formulations (one and two injections), PLGA microsphere formulations (single injection), and a mixture of aluminum and PLGA microsphere formulations (single injection). The nine-month serum antibody titers indicate that a single injection of a mixture of aluminum and PLGA-formulated HBsAg results in equal or better immune responses than two injections of aluminum-formulated HBsAg vaccine. Based on these in vitro and in vivo studies, it is concluded that HBsAg can be successfully encapsulated and recovered from the PLGA microspheres and a mixture of aluminum-adjuvanted and PLGA-formulated HBsAg can auto-boost an immune response in manner comparable to multiple injections of an aluminum

  17. 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

  18. 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.

  19. A novel dengue virus serotype 1 vaccine candidate based on Japanese encephalitis virus vaccine strain SA14-14-2 as the backbone.

    Science.gov (United States)

    Yang, Huiqiang; Li, Zhushi; Lin, Hua; Wang, Wei; Yang, Jian; Liu, Lina; Zeng, Xianwu; Wu, Yonglin; Yu, Yongxin; Li, Yuhua

    2016-06-01

    To develop a potential dengue vaccine candidate, a full-length cDNA clone of a novel chimeric virus was constructed using recombinant DNA technology, with Japanese encephalitis virus (JEV) vaccine strain SA14-14-2 as the backbone, with its premembrane (prM) and envelope (E) genes substituted by their counterparts from dengue virus type 1 (DENV1). The chimeric virus (JEV/DENV1) was successfully recovered from primary hamster kidney (PHK) cells by transfection with the in vitro transcription products of JEV/DENV1 cDNA and was identified by complete genome sequencing and immunofluorescent staining. No neuroinvasiveness of this chimeric virus was observed in mice inoculated by the subcutaneous route (s.c.) or by the intraperitoneal route (i.p.), while some neurovirulence was displayed in mice that were inoculated directly by the intracerebral route (i.c.). The chimeric virus was able to stimulate high-titer production of antibodies against DENV1 and provided protection against lethal challenge with neuroadapted dengue virus in mice. These results suggest that the chimeric virus is a promising dengue vaccine candidate.

  20. Single- and multiple-clade influenza A H5N1 vaccines induce cross protection in ferrets.

    Science.gov (United States)

    Forrest, Heather L; Khalenkov, Alexey M; Govorkova, Elena A; Kim, Jeong-Ki; Del Giudice, Giuseppe; Webster, Robert G

    2009-06-24

    The rapid evolution, genetic diversity, broad host range, and increasing human infection with avian influenza A (H5N1) viruses highlight the need for an efficacious cross-clade vaccine. Using the ferret model, we compared induction of cross-reactive immunity and protective efficacy of three single-clade H5N1 vaccines and a novel multiple-clade H5N1 vaccine, with and without MF59 adjuvant. Reverse genetics (rg) was used to generate vaccine viruses containing the hemagglutinin (HA) and neuraminidase genes of wild-type H5N1 viruses. Ferrets received two doses of inactivated whole-virus vaccine separated by 3 weeks. Single-clade vaccines (7.5 microg HA per dose) included rg-A/Vietnam/1203/04 (clade 1), rg-A/Hong Kong/213/03 (clade 1), and rg-A/Japanese White Eye/Hong Kong/1038/06 (clade 2.3). The multiple-clade vaccine contained 3.75 microg HA per dose of each single-clade vaccine and of rg-A/Whooper Swan/Mongolia/244/05 (clade 2.2). Two doses of vaccine were required to substantially increase anti-HA and virus neutralizing antibody titers to H5N1 viruses. MF59 adjuvant enhanced induction of clade-specific and cross-clade serum antibody responses, reduced frequency of infection (as determined by upper respiratory tract virus shedding and seroconversion data), and eliminated disease signs. The rg-A/Hong Kong/213/03 vaccine induced the highest antibody titers to homologous and heterologous H5N1 viruses, while rg-A/Japanese White Eye/Hong Kong/1038/06 vaccine induced the lowest. The multiple-clade vaccine was broadly immunogenic against clade 1 and 2 viruses. The rg-A/Vietnam/1203/04 vaccine (the currently stockpiled H5N1 vaccine) most effectively reduced upper respiratory tract virus shedding after challenge with clade 1 and 2 viruses. Importantly, all vaccines protected against lethal challenge with A/Vietnam/1203/04 virus and provided cross-clade protection.

  1. Strain sensor based on gourd-shaped single-mode-multimode-single-mode hybrid optical fibre structure.

    Science.gov (United States)

    Tian, Ke; Farrell, Gerald; Wang, Xianfan; Yang, Wenlei; Xin, Yifan; Liang, Haidong; Lewis, Elfed; Wang, Pengfei

    2017-08-07

    A fibre-optic strain sensor based on a gourd-shaped joint multimode fibre (MMF) sandwiched between two single-mode fibres (SMFs) is described both theoretically and experimentally. The cladding layers of the two MMFs are reshaped to form a hemisphere using an electrical arc method and spliced together, yielding the required gourd shape. The gourd-shaped section forms a Fabry-Perot cavity between the ends of two adjacent but non-contacting multimode fibres' core. The effectiveness of the multimode interference based on the Fabry-Perot interferometer (FPI) formed within the multimode inter-fibre section is greatly improved resulting in an experimentally determined strain sensitivity of -2.60 pm/με over the range 0-1000 με. The sensing characteristics for temperature and humidity of this optical fibre strain sensor are also investigated.

  2. 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

  3. Prevention of vertical transmission of Neospora caninum in C57BL/6 mice vaccinated with Brucella abortus strain RB51 expressing N. caninum protective antigens.

    Science.gov (United States)

    Ramamoorthy, Sheela; Sanakkayala, Neelima; Vemulapalli, Ramesh; Jain, Neeta; Lindsay, David S; Schurig, Gerhardt S; Boyle, Stephen M; Sriranganathan, Nammalwar

    2007-11-01

    Bovine abortions caused by the apicomplexan parasite Neospora caninum have been responsible for severe economic losses to the cattle industry. Infected cows either experience abortion or transmit the parasite transplacentally at a rate of up to 95%. Neospora caninum vaccines that can prevent vertical transmission and ensure disruption in the life cycle of the parasite greatly aid in the management of neosporosis in the cattle industry. Brucella abortus strain RB51, a commercially available vaccine for bovine brucellosis, can also be used as a vector to express plasmid-encoded proteins from other pathogens. Neospora caninum protective antigens MIC1, MIC3, GRA2, GRA6 and SRS2 were expressed in strain RB51. Female C57BL/6 mice were vaccinated with a recombinant strain RB51 expressing N. caninum antigen or irradiated tachyzoites, boosted 4 weeks later and then bred. Antigen-specific IgG, IFN-gamma and IL-10 were detected in vaccinated pregnant mice. Vaccinated mice were challenged with 5 x 10(6)N. caninum tachyzoites between days 11-13 of pregnancy. Brain tissue was collected from pups 3 weeks after birth and examined for the presence of N. caninum by real-time PCR. The RB51-MIC3, RB51-GRA6, irradiated tachyzoite vaccine, pooled strain RB51-Neospora vaccine, RB51-MIC1 and RB51-SRS2 vaccines elicited approximately 6-38% protection against vertical transmission. However, the differences in parasite burden in brain tissue of pups from the control and vaccinated groups were highly significant for all groups. Thus, B. abortus strain RB51 expressing the specific N. caninum antigens induced substantial protection against vertical transmission of N. caninum in mice.

  4. 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

  5. Leptospirosis vaccines

    Directory of Open Access Journals (Sweden)

    Jin Li

    2007-12-01

    Full Text Available Abstract Leptospirosis is a serious infection disease caused by pathogenic strains of the Leptospira spirochetes, which affects not only humans but also animals. It has long been expected to find an effective vaccine to prevent leptospirosis through immunization of high risk humans or animals. Although some leptospirosis vaccines have been obtained, the vaccination is relatively unsuccessful in clinical application despite decades of research and millions of dollars spent. In this review, the recent advancements of recombinant outer membrane protein (OMP vaccines, lipopolysaccharide (LPS vaccines, inactivated vaccines, attenuated vaccines and DNA vaccines against leptospirosis are reviewed. A comparison of these vaccines may lead to development of new potential methods to combat leptospirosis and facilitate the leptospirosis vaccine research. Moreover, a vaccine ontology database was built for the scientists working on the leptospirosis vaccines as a starting tool.

  6. 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

  7. Vaccine-driven evolution of Bordetella pertussis: changes in population structure and strain fitness

    NARCIS (Netherlands)

    Loo, Inge Hubertus Maria van

    2002-01-01

    Whooping cough or pertussis is a highly contagious disease of the respiratory tract, caused by Bordetella pertussis. In The Netherlands mass vaccination against B. pertussis was introduced in 1953 and was very effective in reducing the pertussis incidence and mortality. Although vaccination was

  8. 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.

  9. Development of a Novel Vaccine Containing Binary Toxin for the Prevention of Clostridium difficile Disease with Enhanced Efficacy against NAP1 Strains.

    Directory of Open Access Journals (Sweden)

    Susan Secore

    Full Text Available Clostridium difficile infections (CDI are a leading cause of nosocomial diarrhea in the developed world. The main virulence factors of the bacterium are the large clostridial toxins (LCTs, TcdA and TcdB, which are largely responsible for the symptoms of the disease. Recent outbreaks of CDI have been associated with the emergence of hypervirulent strains, such as NAP1/BI/027, many strains of which also produce a third toxin, binary toxin (CDTa and CDTb. These hypervirulent strains have been associated with increased morbidity and higher mortality. Here we present pre-clinical data describing a novel tetravalent vaccine composed of attenuated forms of TcdA, TcdB and binary toxin components CDTa and CDTb. We demonstrate, using the Syrian golden hamster model of CDI, that the inclusion of binary toxin components CDTa and CDTb significantly improves the efficacy of the vaccine against challenge with NAP1 strains in comparison to vaccines containing only TcdA and TcdB antigens, while providing comparable efficacy against challenge with the prototypic, non-epidemic strain VPI10463. This combination vaccine elicits high neutralizing antibody titers against TcdA, TcdB and binary toxin in both hamsters and rhesus macaques. Finally we present data that binary toxin alone can act as a virulence factor in animal models. Taken together, these data strongly support the inclusion of binary toxin in a vaccine against CDI to provide enhanced protection from epidemic strains of C. difficile.

  10. Administering Multiple Injectable Vaccines During a Single Visit-Summary of Findings From the Accelerated Introduction of Inactivated Polio Vaccine Globally.

    Science.gov (United States)

    Dolan, Samantha B; Patel, Manish; Hampton, Lee M; Burnett, Eleanor; Ehlman, Daniel C; Garon, Julie; Cloessner, Emily; Chmielewski, Elizabeth; Hyde, Terri B; Mantel, Carsten; Wallace, Aaron S

    2017-07-01

    In 2013, the World Health Organization's (WHO's) Strategic Advisory Group of Experts (SAGE) recommended that all 126 countries using only oral polio vaccine (OPV) introduce at least 1 dose of inactivated polio vaccine (IPV) into their routine immunization schedules by the end of 2015. In many countries, the addition of IPV would necessitate delivery of multiple injectable vaccines (hereafter, "multiple injections") during a single visit, with infants receiving IPV alongside pentavalent vaccine (which covers diphtheria, tetanus, and whole-cell pertussis; hepatitis B; and Haemophilus influenzae type b) and pneumococcal vaccine. Unanticipated concerns emerged from countries over acceptability of multiple injections, sites of administration, and safety. We contextualized the issues surrounding multiple injections by documenting concerns associated with administration of ≥3 injections, existing evidence in the published literature, and findings of a systematic review on administration practices and techniques. Concerns associated with multiple-injection visits were documented from meetings and personal communications with immunization program managers. Published literature on the acceptability of multiple injections by providers and caregivers was summarized, and a systematic review of the literature on administration practices was completed on the following topics: spacing between injection sites (ie, vaccine spacing), site of injection, route of injection, and procedural preparedness. WHO and United Nations Children's Fund data from 2013-2015 were used to assess multiple-injection visits included in national immunization schedules. Healthcare provider and caregiver attitudes and practices indicated concerns about infant pain, potential adverse effects, and uncertainty about vaccine effectiveness with multiple-injection visits. Published literature reinforced the record of safety and acceptance of the recommended schedule of IPV by the SAGE, but the evidence was

  11. Seropositivity among Korean Young Adults Approximately 2 Years after a Single-Dose Vaccination against Hepatitis A Virus.

    Directory of Open Access Journals (Sweden)

    Yeong-Jun Song

    Full Text Available We previously observed 80.7% seropositivity and a significant interaction between gender and hepatitis A virus (HAV vaccine type (Havrix vs. Epaxal on the seropositivity approximately 11 months after single-dose HAV vaccinations in Korean young adults. Our objective was to evaluate seropositivity approximately 2 years after a single-dose HAV vaccination and the influence of demographic characteristics on seropositivity, including the interaction between gender and vaccine type. Seronegative medical school students were randomly vaccinated with Havrix or Epaxal. Based on a total serum anti-HAV antibody titer cutoff of 20 IU/mL, 338 participants (76.0% of the 445 vaccinees were seropositive 20-25 months after a single-dose HAV vaccination. The seropositive rates were similar after vaccination with Havrix (77.0% and Epaxal (74.9%. Univariate analysis indicated that female (p = 0.052 and less obese (p < 0.001 participants had a higher seropositive rate, whereas other characteristics such as age, alcohol use, smoking history, vaccine type, and follow-up duration were not associated with seropositivity. Multivariate analysis indicated that women (p = 0.026 and participants with moderate alcohol use (p < 0.001 showed significantly higher seropositive rates than men and participants with no or low alcohol use, respectively. The seropositive rates after vaccination with Havrix and Epaxal were 70.9% and 67.5% in men and 87.7% and 91.3% in women, respectively (p for interaction = 0.304. Compared with the seropositive rate approximately 11 months after vaccination, the seropositive rate decreased substantially only in men in the Havrix group (11.0% points, and consequently, the interaction between gender and vaccine type disappeared while seropositivity remained high (87.7% and 91.3% in Havrix and Epaxal groups, respectively among women approximately 2 years after vaccination. Further studies are needed to assess whether the seropositive rate would be

  12. EVALUATION OF OIL BASED AVIAN INFLUENZA VACCINE (H5NI PREPARED WITH DIFFERENT CONCENTRATIONS OF ADJUVANT

    Directory of Open Access Journals (Sweden)

    M. IQBAL, M. NISAR, ANWARUL-HAQ, S. NOOR AND Z. J. GILL

    2008-12-01

    Full Text Available Bird flu vaccine from H5N1 strain of avian influenza virus was prepared with two concentrations of adjuvant (Montanide ISA 70MVG. Two vaccines (I and II were prepared containing 50 and 60% Montanide, respectively. Immune response of both the vaccines as single, as well as booster, dose was evaluated in layer birds through haemagglutination inhibition test. Single dose of both vaccines showed poor immune response, while booster dose gave better response with both the vaccines. However, the vaccine prepared with 60% Montanide provided better immune response compared with the vaccine containing 50% montanide.

  13. Vaccination of cattle with Danish and Pasteur strains of Mycobacterium bovis BCG induce different levels of IFNgamma post-vaccination, but induce similar levels of protection against bovine tuberculosis.

    Science.gov (United States)

    Wedlock, D Neil; Denis, Michel; Vordermeier, H Martin; Hewinson, R Glyn; Buddle, Bryce M

    2007-07-15

    A number of studies have demonstrated significant protection of cattle against bovine tuberculosis following vaccination with the Pasteur strain of Mycobacterium bovis bacille Calmete-Guerin (BCG). However, it is unclear if other daughter strains of BCG are as effective, which is an important issue to resolve for a variety of regulatory compliance issues. This study compared the protective immune responses to bovine tuberculosis induced in cattle vaccinated with BCG Danish with those induced by BCG Pasteur. Groups of calves (n=10) were vaccinated with 10(6) colony forming units (CFU) BCG Pasteur prepared from a fresh liquid culture, 10(6) CFU BCG Danish prepared from a fresh liquid culture or 0.4 mg of reconstituted freeze-dried culture of BCG Danish. Another group (n=10) served as non-vaccinated controls. BCG Pasteur induced significantly higher and more sustained levels of bovine purified protein derivative (PPD)-specific gamma interferon (IFN-gamma) in whole-blood cultures following vaccination compared to either fresh culture BCG Danish or freeze-dried BCG Danish. Vaccination with a fresh culture of BCG Pasteur, fresh culture BCG Danish and freeze-dried BCG Danish gave a significant enhancement in three, four and three pathological and microbiological parameters of protection, respectively, compared to the non-vaccinated group. These results demonstrate the Danish strain of BCG is a viable alternative to BCG Pasteur for vaccination of cattle as both strains had similar efficacy and there was little difference between freshly cultured and freeze-dried formulation of BCG Danish. The results also show that post-vaccination antigen-specific IFN-gamma levels in whole blood is not always a reliable indicator of protection against a subsequent virulent challenge.

  14. 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.

  15. 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.

  16. Compression strain-induced folding at intersecting deformation macrobands on the copper single crystals

    Science.gov (United States)

    Chumaevskii, A. V.; Lychagin, D. V.; Tarasov, S. Yu.

    2017-12-01

    Compression strain-induced surface pattern on copper single crystal faces was studied by means of optical, confocal laser and scanning electron microscopies. It was shown that apart from work-hardening effect of previously formed deformation macrobands there is a pure geometrical (size) effect which serves for changing the conditions for further deformation within the deformation macroband zones by folded structure formation.

  17. Vaccinations

    Science.gov (United States)

    ... will not work well for all pets. Your veterinarian will determine a vaccination schedule most appropriate for ... programs, but in some instances may help your veterinarian determine if your pet has a reasonable expectation ...

  18. 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.

  19. Prevention of lethal experimental infection of C57BL/6 mice by vaccination with Brucella abortus strain RB51 expressing Neospora caninum antigens.

    Science.gov (United States)

    Ramamoorthy, Sheela; Sanakkayala, Neelima; Vemulapalli, Ramesh; Duncan, Robert B; Lindsay, David S; Schurig, Gerhart S; Boyle, Stephen M; Kasimanickam, Ramanathan; Sriranganathan, Nammalwar

    2007-11-01

    Bovine abortions caused by the intracellular protozoal parasite Neospora caninum are a major concern to cattle industries worldwide. A strong Th1 immune response is required for protection against N. caninum. Brucella abortus strain RB51 is currently used as a live, attenuated vaccine against bovine brucellosis. Strain RB51 can also be used as an expression vector for heterologous protein expression. In this study, putative protective antigens of N. caninum MIC1, MIC3, GRA2, GRA6 and SRS2, were expressed individually in B. abortus strain RB51. The ability of each of the recombinant RB51 strains to induce N. caninum-specific immunity was assessed in C57BL/6 mice. Mice were immunised by two i.p. inoculations, 4 weeks apart. Five weeks after the second immunisation, spleen cells from the vaccinated mice secreted high levels of IFN-gamma and IL-10 upon in vitro stimulation with N. caninum whole cell lysate antigens. N. caninum-specific antibodies of both IgG1 and IgG2a subtypes were detected in the serum of the vaccinated mice. Mice in the vaccinated and control groups were challenged with 2 x 10(7)N. caninum tachyzoites i.p. and observed for 28 days after vaccination. All unvaccinated control mice died within 7 days. Mice in the MIC1 and GRA6 vaccine groups were completely protected while the mice in the SRS2, GRA2 and MIC3 vaccinated groups were partially protected and experienced 10-50% mortality. The non-recombinant RB51 vector control group experienced an average protection of 69%. These results suggest that expression of protective antigens of N. caninum in B. abortus strain RB51 is a novel approach towards the development of a multivalent vaccine against brucellosis and neosporosis.

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

    Science.gov (United States)

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

  1. 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...

  2. 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)

  3. Poloxamer 407-chitosan grafted thermoresponsive hydrogels achieve synchronous and sustained release of antigen and adjuvant from single-shot vaccines.

    Science.gov (United States)

    Bobbala, Sharan; Gibson, Blake; Gamble, Allan B; McDowell, Arlene; Hook, Sarah

    2018-03-02

    Sustained release vaccine delivery systems may enhance the immunogenicity of subunit vaccines and reduce the need for multiple vaccinations. The aim of this study was to develop a thermoresponsive hydrogel using poloxamer 407-chitosan (CP) grafted copolymer as a delivery system for single-shot sustained release vaccines. The CP copolymer was synthesized using 1-ethyl-3-(3-dimethylaminopropyl)-carbodiimide (EDC) and N-hydroxysuccinimide (NHS) chemistry. The CP copolymer was a free flowing solution at ambient temperature and transformed rapidly into a gel at body temperature. The hydrogels were loaded with vaccine antigen and adjuvants or the vaccine components were encapsulated in poly (lactic-co-glycolic acid) nanoparticles (PLGA-NP) in order to ensure synchronous release. The CP hydrogels were stable for up to 18 days in vitro. Release of both nanoparticles and the individual components was complete, with release of the individual components being modulated by incorporation into nanoparticles. In vivo, a single dose of CP hydrogel vaccine induced strong, long lasting, cellular and humoral responses that could protect against the development of tumors in a murine melanoma model. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

  4. Long-Term Single-Dose Efficacy of a Vesicular Stomatitis Virus-Based Andes Virus Vaccine in Syrian Hamsters

    Directory of Open Access Journals (Sweden)

    Joseph Prescott

    2014-01-01

    Full Text Available Andes virus (ANDV is highly pathogenic in humans and is the primary etiologic agent of hantavirus cardiopulmonary syndrome (HCPS in South America. Case-fatality rates are as high as 50% and there are no approved vaccines or specific therapies for infection. Our laboratory has recently developed a replication-competent recombinant vesicular stomatitis virus (VSV-based vaccine that expressed the glycoproteins of Andes virus in place of the native VSV glycoprotein (G. This vaccine is highly efficacious in the Syrian hamster model of HCPS when given 28 days before challenge with ANDV, or when given around the time of challenge (peri-exposure, and even protects when administered post-exposure. Herein, we sought to test the durability of the immune response to a single dose of this vaccine in Syrian hamsters. This vaccine was efficacious in hamsters challenged intranasally with ANDV 6 months after vaccination (p = 0.025, but animals were not significantly protected following 1 year of vaccination (p = 0.090. The decrease in protection correlated with a reduction of measurable neutralizing antibody responses, and suggests that a more robust vaccination schedule might be required to provide long-term immunity.

  5. Microscale consolidation analysis of relaxation behavior of single living chondrocytes subjected to varying strain-rates.

    Science.gov (United States)

    Nguyen, Trung Dung; Oloyede, Adekunle; Singh, Sanjleena; Gu, YuanTong

    2015-09-01

    Besides the elastic stiffness, the relaxation behavior of single living cells is also of interest of various researchers when studying cell mechanics. It is hypothesized that the relaxation response of the cells is governed by both intrinsic viscoelasticity of the solid phase and fluid-solid interactions mechanisms. There are a number of mechanical models have been developed to investigate the relaxation behavior of single cells. However, there is lack of model enable to accurately capture both of the mechanisms. Therefore, in this study, the porohyperelastic (PHE) model, which is an extension of the consolidation theory, combined with inverse Finite Element Analysis (FEA) technique was used at the first time to investigate the relaxation response of living chondrocytes. This model was also utilized to study the dependence of relaxation behavior of the cells on strain-rates. The stress-relaxation experiments under the various strain-rates were conducted with the Atomic Force Microscopy (AFM). The results have demonstrated that the PHE model could effectively capture the stress-relaxation behavior of the living chondrocytes, especially at intermediate to high strain-rates. Although this model gave some errors at lower strain-rates, its performance was acceptable. Therefore, the PHE model is properly a promising model for single cell mechanics studies. Moreover, it has been found that the hydraulic permeability of living chondrocytes reduced with decreasing of strain-rates. It might be due to the intracellular fluid volume fraction and the fluid pore pressure gradients of chondrocytes were higher when higher strain-rates applied. Copyright © 2015 Elsevier Ltd. All rights reserved.

  6. 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 (pvaccine 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 Ltd.. All rights

  7. 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.

  8. Enhanced and persistent antibody response against homologous and heterologous strains elicited by a MF59-adjuvanted influenza vaccine in infants and young children.

    Science.gov (United States)

    Nolan, Terry; Bravo, Lulu; Ceballos, Ana; Mitha, Essack; Gray, Glenda; Quiambao, Beatriz; Patel, Sanjay S; Bizjajeva, Svetlana; Bock, Hans; Nazaire-Bermal, Nancy; Forleo-Neto, Eduardo; Cioppa, Giovanni Della; Narasimhan, Vas

    2014-10-21

    Non-adjuvanted seasonal influenza vaccines show only modest efficacy in young children. This study compared the immunogenicity, reactogenicity and safety of the MF59-adjuvanted trivalent subunit vaccine (aTIV) with two non-adjuvanted trivalent vaccines, TIV-1, the non-adjuvanted version of aTIV, and TIV-2, a split virion vaccine. 6078 children received two doses of aTIV (n=3125), TIV-1 (n=1479), or TIV-2 (n=1474) four weeks apart (Days 1 and 29). Children aged 6 to vaccination (Day 50), the aTIV group showed significantly higher geometric mean HI titers and seroconversion rates than the TIV-1 or TIV-2 groups against all homologous and heterologous strains. The difference was enhanced at HI titers ≥110. aTIV elicited a faster, more persistent antibody response, with significantly higher titers in the aTIV group after one vaccination (Day 29) and after six months (Day 209) than in either TIV group. aTIV was more reactogenic than were TIV-1 and TIV-2 but rates of severe adverse events were very low for all three vaccines. In infants and young children, the MF59-adjuvanted vaccine induced substantially faster (after one dose), higher, persistent HI titers than the non-adjuvanted vaccines, with consistently higher seroprotection rates at increased threshold HI titers. This trial is registered at clinicaltrials.gov: NCT01346592. Copyright © 2014 Elsevier Ltd. All rights reserved.

  9. Vaccination with Mycobacterium bovis BCG strains Danish and Pasteur in white-tailed deer (Odocoileus virginianus) experimentally challenged with Mycobacterium bovis.

    Science.gov (United States)

    Palmer, M V; Thacker, T C; Waters, W R

    2009-06-01

    Wildlife reservoirs of Mycobacterium bovis represent serious obstacles to the eradication of tuberculosis in domestic livestock and the cause for many faltering bovine tuberculosis eradication programmes. One approach in dealing with wildlife reservoirs of disease is to interrupt inter-species and intraspecies transmission through vaccination of deer or cattle. To evaluate the efficacy of BCG vaccination in white-tailed deer, 35 deer were assigned to one of three groups; one s.c. dose of 10(7) CFU of M. bovis BCG Pasteur (n = 12); 1 s.c. dose of 10(7) CFU of M. bovis BCG Danish (n = 11); or unvaccinated deer (n = 12). After vaccination, deer were inoculated intratonsilarly with virulent M. bovis. Lesion severity scores of the medial retropharyngeal lymph node, as well as all lymph nodes combined, were reduced in vaccinated deer compared to unvaccinated deer. BCG Danish vaccinated deer had no late stage granulomas characterized by coalescent caseonecrotic granulomas containing numerous acid-fast bacilli compared to BCG Pasteur vaccinated or unvaccinated deer where such lesions were present. Both BCG strains were isolated as late as 250 days after vaccination from deer that were vaccinated but not challenged. In white-tailed deer, BCG provides protection against challenge with virulent M. bovis. Issues related to vaccine persistence, safety and shedding remain to be further investigated.

  10. Substructure based modeling of nickel single crystals cycled at low plastic strain amplitudes

    Science.gov (United States)

    Zhou, Dong

    In this dissertation a meso-scale, substructure-based, composite single crystal model is fully developed from the simple uniaxial model to the 3-D finite element method (FEM) model with explicit substructures and further with substructure evolution parameters, to simulate the completely reversed, strain controlled, low plastic strain amplitude cyclic deformation of nickel single crystals. Rate-dependent viscoplasticity and Armstrong-Frederick type kinematic hardening rules are applied to substructures on slip systems in the model to describe the kinematic hardening behavior of crystals. Three explicit substructure components are assumed in the composite single crystal model, namely "loop patches" and "channels" which are aligned in parallel in a "vein matrix," and persistent slip bands (PSBs) connected in series with the vein matrix. A magnetic domain rotation model is presented to describe the reverse magnetostriction of single crystal nickel. Kinematic hardening parameters are obtained by fitting responses to experimental data in the uniaxial model, and the validity of uniaxial assumption is verified in the 3-D FEM model with explicit substructures. With information gathered from experiments, all control parameters in the model including hardening parameters, volume fraction of loop patches and PSBs, and variation of Young's modulus etc. are correlated to cumulative plastic strain and/or plastic strain amplitude; and the whole cyclic deformation history of single crystal nickel at low plastic strain amplitudes is simulated in the uniaxial model. Then these parameters are implanted in the 3-D FEM model to simulate the formation of PSB bands. A resolved shear stress criterion is set to trigger the formation of PSBs, and stress perturbation in the specimen is obtained by several elements assigned with PSB material properties a priori. Displacement increment, plastic strain amplitude control and overall stress-strain monitor and output are carried out in the user

  11. 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.

  12. Sequence-specific detection of different strains of LCMV in a single sample using tentacle probes.

    Science.gov (United States)

    Franco, Lina S; Holechek, Susan A; Caplan, Michael R; Blattman, Joseph N

    2017-10-13

    Virus infections often result in quasispecies of viral strains that can have dramatic impacts on disease outcomes. However, sequencing of viruses to determine strain composition is time consuming and often cost-prohibitive. Rapid, cost-effective methods are needed for accurate measurement of virus diversity to understand virus evolution and can be useful for experimental systems. We have developed a novel molecular method for sequence-specific detection of RNA virus genetic variants called Tentacle Probes. The probes are modified molecular beacons that have dramatically improved false positive rates and specificity in routine qPCR. To validate this approach, we have designed Tentacle Probes for two different strains of Lymphocytic Choriomeningitis Virus (LCMV) that differ by only 3 nucleotide substitutions, the parental Armstrong and the more virulent Clone-13 strain. One of these mutations is a missense mutation in the receptor protein GP1 that leads to the Armstrong strain to cause an acute infection and Clone-13 to cause a chronic infection instead. The probes were designed using thermodynamic calculations for hybridization between target or non-target sequences and the probe. Using this approach, we were able to distinguish these two strains of LCMV individually by a single nucleotide mutation. The assay showed high reproducibility among different concentrations of viral cDNA, as well as high specificity and sensitivity, especially for the Clone-13 Tentacle Probe. Furthermore, in virus mixing experiments we were able to detect less than 10% of Clone-13 cDNA diluted in Armstrong cDNA. Thus, we have developed a fast, cost-effective approach for identifying Clone-13 strain in a mix of other LCMV strains.

  13. A Japanese encephalitis virus vaccine candidate strain is attenuated by decreasing its interferon antagonistic ability.

    Science.gov (United States)

    Liang, Jian-Jong; Liao, Ching-Len; Liao, Jia-Teh; Lee, Yi-Ling; Lin, Yi-Ling

    2009-05-11

    Japanese encephalitis virus (JEV) is a mosquito-borne flavivirus that causes acute encephalitis with high mortality in humans. To understand the virus-host interactions that influence JEV virulence, we determined the lethality of a neurovirulent (RP-9) and an attenuated (RP-2ms) variant of JEV in several immunodeficient mice strains. The attenuated phenotype of RP-2ms was completely lost in Stat-1-deficient mice, but its virulence was only slightly increased in mice lacking the components of adaptive immunity, suggesting an important role of the interferon (IFN) system in controlling JEV infection. Cell-based assays demonstrated that RP-2ms is more sensitive to IFN-alpha treatment; however, the NS5 protein of RP-2ms was still a potent antagonist of IFN, like RP-9 NS5. Using a recombinant infectious clone of RP-9, we found that a single Glu-->Lys mutation at residue 138 of the envelope protein (E-E138K) rendered the mutated RP-9 sensitive to the antiviral effect of IFN-alpha. Furthermore, IFN signaling was blocked earlier in the RP-9-infected cells relative to that in cells infected with RP-2ms or recombinant RP-9 bearing the E-E138K mutation. Thus, the E-E138K mutation of JEV appears to affect the viral growth properties, leading to a reduced efficiency in blocking IFN signaling, which then results in an attenuated phenotype in inoculated animals.

  14. 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.

  15. Children with Haemophilus influenzae type b (Hib) vaccine failure have long-term bactericidal antibodies against virulent Hib strains with multiple capsular loci.

    Science.gov (United States)

    Townsend-Payne, Kelly; Ladhani, Shamez N; Findlow, Helen; Slack, Mary; Borrow, Ray

    2016-07-25

    Children who develop invasive Haemophilus influenzae serotype b (Hib) disease after immunisation with a highly-effective conjugate vaccine are more likely to have been infected with Hib strains possessing multiple copies of the capsulation locus. Using a recently-validated serum bactericidal antibody (SBA) assay, we tested convalescent sera from 127 Hib vaccine failure cases against clinical Hib strains expressing 1-5 copies of the capsulation locus. SBA titres correlated weakly with anti-capsular IgG antibody concentrations and there was no association between SBA geometric mean titres and number of capsulation locus copies. After infection, children with Hib vaccine failure were equally protected against Hib strains with 1-5 copies of the capsulation locus. Copyright © 2016. Published by Elsevier Ltd.

  16. Can a single dose of human papillomavirus (HPV) vaccine prevent cervical cancer? Early findings from an Indian study.

    Science.gov (United States)

    Sankaranarayanan, Rengaswamy; Joshi, Smita; Muwonge, Richard; Esmy, Pulikottil Okkuru; Basu, Partha; Prabhu, Priya; Bhatla, Neerja; Nene, Bhagwan M; Shaw, Janmesh; Poli, Usha Rani Reddy; Verma, Yogesh; Zomawia, Eric; Pimple, Sharmila; Tommasino, Massimo; Pawlita, Michael; Gheit, Tarik; Waterboer, Tim; Sehr, Peter; Pillai, Madhavan Radhakrishna

    2018-03-15

    Human papillomavirus (HPV) vaccination is a major strategy for preventing cervical and other ano-genital cancers. Worldwide HPV vaccination introduction and coverage will be facilitated if a single dose of vaccine is as effective as two or three doses or demonstrates significant protective effect compared to 'no vaccination'. In a multi-centre cluster randomized trial of two vs three doses of quadrivalent HPV vaccination (Gardasil™) in India, suspension of the vaccination due to events unrelated to the study led to per protocol and partial vaccination of unmarried 10-18 year old girls leading to four study groups, two by design and two by default. They were followed up for the primary outcomes of immunogenicity in terms of L1 genotype-specific binding antibody titres, neutralising antibody titres, and antibody avidity for the vaccine-targeted HPV types and HPV infections. Analysis was per actual number of vaccine doses received. This study is registered with ISRCTN, number ISRCTN98283094; and with ClinicalTrials.gov, number NCT00923702. Of the 17,729 vaccinated girls, 4348 (25%) received three doses on days 1, 60, 180 or later, 4979 (28%) received two doses on days 1 and 180 or later, 3452 (19%) received two doses on days 1 and 60, and 4950 (28%) received one dose. One dose recipients demonstrated a robust and sustained immune response against HPV 16 and 18, albeit inferior to that of 3- or 2-doses and the antibody levels were stable over a 4 year period. The frequencies of cumulative incident and persistent HPV 16 and 18 infections up to 7 years of follow-up were similar and uniformly low in all the vaccinated study groups; the frequency of HPV 16 and 18 infections were significantly higher in unvaccinated age-matched control women than among vaccine recipients. The frequency of vaccine non-targeted HPV types was similar in the vaccinated groups but higher in the unvaccinated control women. Our results indicate that a single dose of quadrivalent HPV

  17. 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.

  18. Exploration of mechanisms underlying the strain-rate-dependent mechanical property of single chondrocytes

    Energy Technology Data Exchange (ETDEWEB)

    Nguyen, Trung Dung; Gu, YuanTong, E-mail: yuantong.gu@qut.edu.au [School of Chemistry, Physics and Mechanical Engineering, Queensland University of Technology, Brisbane, Queensland (Australia)

    2014-05-05

    Based on the characterization by Atomic Force Microscopy, we report that the mechanical property of single chondrocytes has dependency on the strain-rates. By comparing the mechanical deformation responses and the Young's moduli of living and fixed chondrocytes at four different strain-rates, we explore the deformation mechanisms underlying this dependency property. We found that the strain-rate-dependent mechanical property of living cells is governed by both of the cellular cytoskeleton and the intracellular fluid when the fixed chondrocytes are mainly governed by their intracellular fluid, which is called the consolidation-dependent deformation behavior. Finally, we report that the porohyperelastic constitutive material model which can capture the consolidation-dependent behavior of both living and fixed chondrocytes is a potential candidature to study living cell biomechanics.

  19. 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

  20. 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.

  1. Effects of vaccine strain mutations in domain V of the internal ribosome entry segment compared in the wild type poliovirus type 1 context.

    Science.gov (United States)

    Malnou, Cécile E; Werner, Andreas; Borman, Andrew M; Westhof, Eric; Kean, Katherine M

    2004-03-12

    Initiation of poliovirus (PV) protein synthesis is governed by an internal ribosome entry segment structured into several domains including domain V, which is accepted to be important in PV neurovirulence because it harbors an attenuating mutation in each of the vaccine strains developed by A. Sabin. To better understand how these single point mutations exert their effects, we placed each of them into the same genomic context, that of PV type 1. Only the mutation equivalent to the Sabin type 3 strain mutation resulted in significantly reduced viral growth both in HeLa and neuroblastoma cells. This correlated with poor translation efficiency in vitro and could be explained by a structural perturbation of the domain V of the internal ribosome entry segment, as evidenced by RNA melting experiments. We demonstrated that reduced cell death observed during infection by this mutant is due to the absence of inhibition of host cell translation. We confirmed that this shut-off is correlated principally with cleavage of eIF4GII and not eIF4GI and that this cleavage is significantly impaired in the case of the defective mutant. These data support the previously reported conclusion that the 2A protease has markedly different affinities for the two eIF4G isoforms.

  2. 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

  3. Fallacy of the Unique Genome: Sequence Diversity within SingleHelicobacter pyloriStrains.

    Science.gov (United States)

    Draper, Jenny L; Hansen, Lori M; Bernick, David L; Abedrabbo, Samar; Underwood, Jason G; Kong, Nguyet; Huang, Bihua C; Weis, Allison M; Weimer, Bart C; van Vliet, Arnoud H M; Pourmand, Nader; Solnick, Jay V; Karplus, Kevin; Ottemann, Karen M

    2017-02-21

    Many bacterial genomes are highly variable but nonetheless are typically published as a single assembled genome. Experiments tracking bacterial genome evolution have not looked at the variation present at a given point in time. Here, we analyzed the mouse-passaged Helicobacter pylori strain SS1 and its parent PMSS1 to assess intra- and intergenomic variability. Using high sequence coverage depth and experimental validation, we detected extensive genome plasticity within these H. pylori isolates, including movement of the transposable element IS 607 , large and small inversions, multiple single nucleotide polymorphisms, and variation in cagA copy number. The cagA gene was found as 1 to 4 tandem copies located off the cag island in both SS1 and PMSS1; this copy number variation correlated with protein expression. To gain insight into the changes that occurred during mouse adaptation, we also compared SS1 and PMSS1 and observed 46 differences that were distinct from the within-genome variation. The most substantial was an insertion in cagY , which encodes a protein required for a type IV secretion system function. We detected modifications in genes coding for two proteins known to affect mouse colonization, the HpaA neuraminyllactose-binding protein and the FutB α-1,3 lipopolysaccharide (LPS) fucosyltransferase, as well as genes predicted to modulate diverse properties. In sum, our work suggests that data from consensus genome assemblies from single colonies may be misleading by failing to represent the variability present. Furthermore, we show that high-depth genomic sequencing data of a population can be analyzed to gain insight into the normal variation within bacterial strains. IMPORTANCE Although it is well known that many bacterial genomes are highly variable, it is nonetheless traditional to refer to, analyze, and publish "the genome" of a bacterial strain. Variability is usually reduced ("only sequence from a single colony"), ignored ("just publish the

  4. Construction of a recombinant duck enteritis virus (DEV) expressing hemagglutinin of H5N1 avian influenza virus based on an infectious clone of DEV vaccine strain and evaluation of its efficacy in ducks and chickens.

    Science.gov (United States)

    Wang, Jichun; Ge, Aimin; Xu, Mengwei; Wang, Zhisheng; Qiao, Yongfeng; Gu, Yiqi; Liu, Chang; Liu, Yamei; Hou, Jibo

    2015-08-13

    Highly pathogenic avian influenza virus (AIV) subtype H5N1 remains a threat to poultry. Duck enteritis virus (DEV)-vectored vaccines expressing AIV H5N1 hemagglutinin (HA) may be viable AIV and DEV vaccine candidates. To facilitate the generation and further improvement of DEV-vectored HA(H5) vaccines, we first constructed an infectious clone of DEV Chinese vaccine strain C-KCE (DEV(C-KCE)). Then, we generated a DEV-vectored HA(H5) vaccine (DEV-H5(UL55)) based on the bacterial artificial chromosome (BAC) by inserting a synthesized HA(H5) expression cassette with a pMCMV IE promoter and a consensus HA sequence into the noncoding area between UL55 and LORF11. The immunogenicity and protective efficacy of the resulting recombinant vaccine against DEV and AIV H5N1 were evaluated in both ducks and chickens. The successful construction of DEV BAC and DEV-H5(UL55) was verified by restriction fragment length polymorphism analysis. Recovered virus from the BAC or mutants showed similar growth kinetics to their parental viruses. The robust expression of HA in chicken embryo fibroblasts infected with the DEV-vectored vaccine was confirmed by indirect immunofluorescence and western blotting analyses. A single dose of 10(6) TCID50 DEV-vectored vaccine provided 100 % protection against duck viral enteritis in ducks, and the hemagglutination inhibition (HI) antibody titer of AIV H5N1 with a peak of 8.2 log2 was detected in 3-week-old layer chickens. In contrast, only very weak HI titers were observed in ducks immunized with 10(7) TCID50 DEV-vectored vaccine. A mortality rate of 60 % (6/10) was observed in 1-week-old specific pathogen free chickens inoculated with 10(6) TCID50 DEV-vectored vaccine. We demonstrate the following in this study. (i) The constructed BAC is a whole genome clone of DEV(C-KCE). (ii) The insertion of an HA expression cassette sequence into the noncoding area between UL55 and LORF11 of DEV(C-KCE) affects neither the growth kinetics of the virus nor its

  5. Amplification of the Matrix Gene of RBOK Vaccine Strain of Rinderpest Virus (RPV) by Polymerase Chain Reaction and Cloning into TOPOR XL Cloning Vector

    OpenAIRE

    AZKUR, Ahmet Kürşat; BOLAT, Yusuf

    2003-01-01

    In this study, the matrix (M) gene of the RBOK vaccine strain of rinderpest (RPV) was amplified by polymerase chain reaction (PCR) and cloned into TOPOR XL cloning vector. For this purpose, Vero cells were infected with the RBOK vaccine strain of RPV and total RNA was obtained from the infected cells. cDNA of the matrix gene was obtained by reverse transcription from the total RNA. Amplification of the cDNA with PCR was achieved by using the M gene specific primer and PCR products of the M ge...

  6. Fallacy of the Unique Genome: Sequence Diversity within Single Helicobacter pylori Strains

    OpenAIRE

    Draper, JL; Hansen, LM; Bernick, DL; Abedrabbo, S; Underwood, JG; Kong, N; Huang, BC; Weis, AM; Weimer, BC; van Vliet, AHM; Pourmand, N; Solnick, JV; Karplus, K; Ottemannc, KM

    2017-01-01

    © 2017 Doberenz et al. Many bacterial genomes are highly variable but nonetheless are typically published as a single assembled genome. Experiments tracking bacterial genome evolution have not looked at the variation present at a given point in time. Here, we analyzed the mouse-passaged Helicobacter pylori strain SS1 and its parent PMSS1 to assess intra-and intergenomic variability. Using high sequence coverage depth and experimental validation, we detected extensive genome plasticity within ...

  7. Characterization of strained InGaAs single quantum well structures by ion beam methods

    International Nuclear Information System (INIS)

    Yu, K.M.; Chan, K.T.

    1990-01-01

    We have investigated strained InGaAs single quantum well structures using MeV ion beam methods. The structural properties of these structures, including composition and well size, have been studied. It has been found that the composition obtained by Rutherford backscattering spectrometry and particle-induced x-ray emission techniques agrees very well with that obtained by the ion channeling method

  8. Respons Antibodi terhadap Penyakit Tetelo pada Ayam yang Divaksin Tetelo dan Tetelo-Flu Burung (NEWCASTLE DISEASE/ND ANTIBODY RESPONSE OF CHICKENS VACCINATED WITH ND SINGLE AND COMBINED ND AND AVIAN INFLUENZA VACCINES

    Directory of Open Access Journals (Sweden)

    Gusti Ayu Yuniati Kencana

    2015-08-01

    Full Text Available The aim of this study was to investigate antibody response of specific pathogen-free (SPF chickens vaccinatedwith single inactivated Newcastle disease (ND vaccine and combined inactive ND and avian influenza(AI vaccines and to known the efficacy of both vaccines. The vaccines used were killed ND vaccine andkilled ND-AI vaccine produced by PT. Sanbio Laboratories Bogor, West Java. SPF chickens were vaccinatedwith 3 different doses. Antibody titer of SPF chickens against ND virus were determined byhaemagglutination inhibition (HI test. As many as 130 two week old SPF chickens were used and theywere divided into 2 groups (A and B consisting of 60 chickens and 10 chickens were used as control withoutvaccine. Group A chickens were vaccinated with ND-K vaccine and group B were vaccinated with combinedkilled ND-AI vaccines. Each group was further divided into 3 subsgroups (1, 2 and 3 consisting 20 chickens.Subgroups 1, 2 and 3 were vaccinated intramuscularly respectively with intramuskular 1, 1/10 and 1/100doses of each vaccines. Antibody response of chickens against ND virus was examined before vaccinationand every three week after vaccination and was expresses as geometric mean titre (GMT HI units. Theresult showed that the titre antibody against ND increased at the second week following the vaccination.The antibody titer against ND virus of chickens vaccinated single killed ND at the second week in eachdose were 6.05 GMT HI unit, 4.05 GMT HI unit, and 0.9 GMT HI unit. The antibody titre at the third week were 7.90 GMT HI unit ,5.40 GMT HI unit and 2.20 GMT HI unit. The antibody titre against ND virus ofchickens vaccinated with combined ND-AI vaccine at the second week were 6.30 GMT HI unit , 4.15 GMTHI unit , and 2.05 GMT HI unit. At the third week, the antibody titre against ND virus of chickensvaccinated with combined ND-AI vaccine in each subgroup were 7.45 GMT HI unit, 5.60 GMT HI unit , and2.40 GMT HI unit . It showed that the antibody titers

  9. 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.

  10. A Matched Influenza Vaccine Strain Was Effective in Reducing the Risk of Acute Myocardial Infarction in Elderly Persons: A Population-Based Study.

    Science.gov (United States)

    Hsu, Shu-Yun; Chen, Fong-Lin; Liaw, Yung-Po; Huang, Jing-Yang; Nfor, Oswald Ndi; Chao, Day-Yu

    2016-03-01

    The aim of this study was to explore whether matched or mismatched strains of influenza vaccines (IVs) are beneficial at reducing the risk of acute myocardial infarction (AMI) in elderly persons.Data were obtained from the Longitudinal Health Database 2005 (LHID 2005) which is maintained by the National Health Insurance Research Institute in Taiwan. The analytical data included individuals who were vaccinated with mismatched vaccines during the October 2007 to December 2007 season and individuals vaccinated with matched strains during the October 2008 to December 2008 season. All participants were 65 years of age and older. In this analysis, individuals were considered to be exposed if their records showed that they were vaccinated against influenza, and they were considered to be nonexposed if they were not vaccinated during these seasons. A Cox hazard model was used to estimate AMI hazard ratio.This study enrolled 93,051 exposed and 109,007 unexposed individuals. The AMI hazards ratios (HRs) for the men and women exposed to mismatched vaccine (in 2007) were 0.990 (95% confidence interval [CI], 0.745-1.316) and 1.102 (95% CI: 0.803-1.513), respectively. Men exposed to matched vaccines (in 2008) had significant HRs (HR: 0.681; 95% CI: 0.509-0.912) while the HRs in the women were barely significant (HR: 0.737; 95% CI: 0.527-1.029).AMI risk could be particularly reduced in men if the IV matches well with the circulating strains in elderly people 65 years of age and older.

  11. Comparative Study of Three Vaccinal Strains of Clostridium tetani Including Harvard 52, G5 and 49205 from Standpoint of Six Essential Factors to Evaluate Their Toxigenesis for Use in Tetanus Vaccine Production

    Directory of Open Access Journals (Sweden)

    Motedayen, M.H.

    2012-11-01

    Full Text Available Tetanus is an important disease which created by tetanospasmin toxin of Clostridium tetani. In this study we surveyed six important factors including LF, KF, MLD, pH, OD and total protein assay of Harvard 52 (H52, G5 (HG5 and 49205 (H49205 strains of the bacterium to determine which of them were more suitable for use in vaccine production. The mentioned strains were seperatedly reactivated in thioglycolate medium, 2ml of this suspension was used to inoculate the Muller-Miller medium of each of sixteen 500 ml Erlenmeyer flasks (7,6 and 3 flasks for H52, HG5 and H49205 respectively, where the fermentation runs were performed. Over a period of seven days of experiment, several tests for evaluation of the six mentioned factors on samples of medium cultures were carried out. Results revealed that H52 strain had significantly lower values in LF and OD compared to strains HG5 & H49205 (P<0.001 and P<0.01 respectively while its MLD and pH were better than other strains (P< 0.05 and P< 0.02 respectively. In conclusion, it seems that HG5 & H49205 strains have been greater toxin producer than H52 strain and as a result, we hope that with some complementary works, these two strains such as H52 strain, be used for routine tetanus vaccine production.

  12. Protective immune response of oral rabies vaccine in stray dogs, corsacs and steppe wolves after a single immunization.

    Science.gov (United States)

    Zhugunissov, K; Bulatov, Ye; Taranov, D; Yershebulov, Z; Koshemetov, Zh; Abduraimov, Ye; Kondibayeva, Zh; Samoltyrova, A; Amanova, Zh; Khairullin, B; Sansyzbay, A

    2017-11-01

    In this study the safety and protective immunity of an oral rabies vaccine, based on the live, modified rabies virus strain VRC-RZ2, was examined in stray dogs (Canis Sp.), corsacs (Vulpes corsac) and steppe wolves (Canis lupus campestris). In the safety group (dogs, n=6; corsacs, n=3; wolves, n=3) which was vaccinated with a 10-times field dose/animal, no animals showed any signs of disease or changes in behavior or appetite during the period of clinical observation, similar to the animals in the negative control group. Saliva samples taken from animals prior and post (5 th and 10 th days) vaccination failed to demonstrate rabies virus antigen. Observations of immunogenicity in vaccinated carnivores (dogs, corsacs and wolves) during a 180 day period showed the titers of virus neutralizing antibodies (VNA) in the blood sera of vaccinated dogs to be within 0.59-1.37 IU/mL. On 14 days post vaccination (dpv), all the wild carnivores had detectable levels of neutralizing antibodies, with mean titers ranging from 0.50 ± 0.07 IU/mL (for wolves) to 0.59 ± 0.10 IU/mL (for corsacs). Weeks after vaccination, all the vaccinated wolves and corsacs had higher levels of neutralizing antibodies: 0.70 ± 0.10 - 0.71 ± 0.08 IU/mL at 30 dpv, 1.06 ± 0.08 - 1.28 ± 0.21 IU/mL at 60 dpv and 0.41 ± 0.09 - 047 ± 0.06 at 180 dpv. The highest level of VNA (˃1.0 IU/ml) was detected at 60 dpv, in all vaccinated animals. After challenge all vaccinated dogs remained healthy for 180 days. Control animals (unvaccinated dogs) developed symptoms of rabies on day 6 post administration of a virulent virus and died of rabies on days 11-13. Of note, the VNA titers in all the wild carnivores (corsacs and wolves) immunized with VRC-RZ2 were higher than 0.5 IU/ml (0.59 ± 0.11 IU/ml), even as early as 14 days post vaccination. These, presumably protective, titers of antibodies to rabies virus were present in the dogs and wild carnivores examined in this study for at

  13. [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.

  14. High resolution discrimination of clinical Mycobacterium tuberculosis complex strains based on single nucleotide polymorphisms.

    Directory of Open Access Journals (Sweden)

    Susanne Homolka

    Full Text Available Recently, the diversity of the Mycobacterium tuberculosis complex (MTBC population structure has been described in detail. Based on geographical separation and specific host pathogen co-evolution shaping MTBC virulence traits, at least 20 major lineages/genotypes have evolved finally leading to a clear influence of strain genetic background on transmissibility, clinical presentation/outcome, and resistance development. Therefore, high resolution genotyping for characterization of strains in larger studies is mandatory for understanding mechanisms of host-pathogen-interaction and to improve tuberculosis (TB control. Single nucleotide polymorphisms (SNPs represent the most reliable markers for lineage classification of clinical isolates due to the low levels of homoplasy, however their use is hampered either by low discriminatory power or by the need to analyze a large number of genes to achieve higher resolution. Therefore, we carried out de novo sequencing of 26 genes (approx. 20000 bp per strain in a reference collection of MTBC strains including all major genotypes to define a highly discriminatory gene set. Overall, 161 polymorphisms were detected of which 59 are genotype-specific, while 13 define deeper branches such as the Euro-American lineage. Unbiased investigation of the most variable set of 11 genes in a population based strain collection (one year, city of Hamburg, Germany confirmed the validity of SNP analysis as all strains were classified with high accuracy. Taken together, we defined a diagnostic algorithm which allows the identification of 17 MTBC phylogenetic lineages with high confidence for the first time by sequencing analysis of just five genes. In conclusion, the diagnostic algorithm developed in our study is likely to open the door for a low cost high resolution sequence/SNP based differentiation of the MTBC with a very high specificity. High throughput assays can be established which will be needed for large association

  15. Single-dose monomeric HA subunit vaccine generates full protection from influenza challenge

    CSIR Research Space (South Africa)

    Mallajosyula, JK

    2014-03-01

    Full Text Available Recombinant subunit vaccines are an efficient strategy to meet the demands of a possible influenza pandemic, because of rapid and scalable production. However, vaccines made from recombinant hemagglutinin (HA) subunit protein are often of low...

  16. A foot-and-mouth disease SAT2 vaccine protects swine against experimental challenge with a homologous virus strain, irrespective of mild pathogenicity in this species.

    Science.gov (United States)

    Mouton, Laure; Dekker, Aldo; Bleijenberg, Meindert; Blanchet, Michel; Coco-Martin, Jose; Hudelet, Pascal; Goutebroze, Sylvain

    2018-04-05

    FMDV serotype SAT2 is most frequently associated with outbreaks in ruminants. However, the risk of it spreading from cattle to pigs cannot be excluded. To assess the efficacy of an SAT2-type FMD inactivated vaccine against homologous challenge in pigs, a suitable challenge strain adapted to pigs was produced. After two passages in two pigs each, a FMDV stock of SAT2 challenge strain was produced. This material was used to infect two groups of five pigs. The first group being vaccinated 28 days before challenge and the other one left as an unvaccinated control. Clinical signs were recorded, virus shedding was assessed on mouth swabs, and neutralising antibody titres were determined. At least 80% of the vaccinated pigs were protected against clinical disease. Furthermore, no virus shedding was observed in any of the vaccinated pigs. This study shows that experimentally inoculated pigs can become infected with a SAT2 serotype. Furthermore, vaccination offers protection against generalisation and viral excretion, confirming the potential of vaccination as an important tool in the control of FMD in pigs. Copyright © 2018 The Author(s). Published by Elsevier Ltd.. All rights reserved.

  17. Immune responses and protection against experimental Brucella suis biovar 1 challenge in nonvaccinated or B. abortus strain RB51-vaccinated cattle.

    Science.gov (United States)

    Olsen, S C; Hennager, S G

    2010-12-01

    Twenty Hereford heifers approximately 9 months of age were vaccinated with saline (control) or 2 × 10(10) CFU of the Brucella abortus strain RB51 (RB51) vaccine. Immunologic responses after inoculation demonstrated significantly greater (P RB51 antigens in cattle vaccinated with RB51 than in the controls. Pregnant cattle received a conjunctival challenge at approximately 6 months of gestation with 10(7) CFU of B. suis bv. 1 strains isolated from naturally infected cattle. The fluorescence polarization assay and the buffered acid plate agglutination test had the highest sensitivities in detecting B. suis-infected cattle between 2 and 12 weeks after experimental infection. Serologic responses and lymphocyte proliferative responses to B. suis antigens did not differ between control and RB51 vaccinees after experimental infection. No abortions occurred in cattle in either treatment group after challenge, although there appeared to be an increased incidence of retained placenta after parturition in both the control and the RB51 vaccination treatment groups. Our data suggest that the mammary gland is a preferred site for B. suis localization in cattle. Vaccination with RB51 did not reduce B. suis infection rates in maternal or fetal tissues. In conclusion, although B. suis is unlikely to cause abortions and fetal losses in cattle, our data suggest that RB51 vaccination will not protect cattle against B. suis infection after exposure.

  18. [Hog cholera virus: influence of colostral passive antibody on immune response of pig following vaccination with the rabbit adapted Chinese strain (author's transl)].

    Science.gov (United States)

    Mierzejewska, M; Tereszczuk, S; Corthier, G; Aynaud, J M

    1977-01-01

    Using the rabbit adapted chinese strain of Hog cholera, active immunization of piglets having passive colostral antibodies was studied. 65 piglets born from 11 sows were used. Concerning sows, vaccination was performed 5-6 months and 1 month before service (3 sows), 30 days (2 sows) and 60 days (3 sows) after service. Divided in 5 lots, piglets were vaccinated at 4 different periods after birth (15, 30, 60 and 90 days). Hog cholera immunity was determined for each animal by means of kinetic of serum neutralizing antibodies and resistance to virulent challenge performed 5 months after birth. High levels of neutralizing antibodies were observed in serum of each vaccinated sow at the time of farrowing. In piglets having ingested low quantities of colostrum, vaccination induces a good antigenic stimulation characterized by a normal humoral immune response and challenge resistance. But in piglets having ingested a normal quantities of colostrum, colostral passive antibodies have a partial or complete suppressive effect on primary immune response which is characterized by a delay in serum antibodies formation and by a low level at the time of challenge. According the conditions of sows vaccination, differences were observed in the properties of colostral passive antibodies (intensity of suppressive effect on active immune response, in vitro "avidity" for Hog cholera virus, mean value of half-life) present in piglets serum. On practical aspect, vaccination with the chinese strain becomes fully effective in piglets having passive immunity when they are 30-60 days old.

  19. 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...

  20. 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

  1. An attenuated EIAV vaccine strain induces significantly different immune responses from its pathogenic parental strain although with similar in vivo replication pattern.

    Science.gov (United States)

    Lin, Yue-Zhi; Shen, Rong-Xian; Zhu, Zhen-Ying; Deng, Xi-Lin; Cao, Xue-Zhi; Wang, Xue-Feng; Ma, Jian; Jiang, Cheng-Gang; Zhao, Li-Ping; Lv, Xiao-Ling; Shao, Yi-Ming; Zhou, Jian-Hua

    2011-11-01

    The EIAV (equine infectious anemia virus) multi-species attenuated vaccine EIAV(DLV121) successfully prevented the spread of equine infectious anemia (EIA) in China in the 1970s and provided an excellent model for the study of protective immunity to lentiviruses. In this study, we compared immune responses induced by EIAV(DLV121) to immunity elicited by the virulent EIAV(LN40) strain and correlated immune responses to protection from infection. Horses were randomly grouped and inoculated with either EIAV(DLV121) (Vaccinees, Vac) or a sublethal dose of EIAV(LN40) (asymptomatic carriers, Car). Car horses became EIAV(LN40) carriers without disease symptoms. Two of the four Vac horses were protected against infection and the other two had delayed onset or reduced severity of EIA with a lethal EIAV(LN40) challenge 5.5 months post initial inoculation. In contrast, all three Car animals developed acute EIA and two succumbed to death. Specific humoral and cellular immune responses in both Vac and Car groups were evaluated for potential correlations with protection. These analyses revealed that although plasma viral loads remained between 10(3) and 10(5)copies/ml for both groups before EIAV(LN40) challenge, Vac-treated animals developed significantly higher levels of conformational dependent, Env-specific antibody, neutralizing antibody as well as significantly elevated CD4(+) T cell proliferation and IFN-γ-secreting CD8(+) T cells than those observed in EIAV(LN40) asymptomatic carriers. Further analysis of protected and unprotected cases in vaccinated horses identified that cellular response parameters and the reciprocal anti-p26-specific antibody titers closely correlated with protection against infection with the pathogenic EIAV(LN40). These data provide a better understanding of protective immunity to lentiviruses. Copyright © 2011 Elsevier B.V. All rights reserved.

  2. Assessment of continuum mechanics models in predicting buckling strains of single-walled carbon nanotubes.

    Science.gov (United States)

    Zhang, Y Y; Wang, C M; Duan, W H; Xiang, Y; Zong, Z

    2009-09-30

    This paper presents an assessment of continuum mechanics (beam and cylindrical shell) models in the prediction of critical buckling strains of axially loaded single-walled carbon nanotubes (SWCNTs). Molecular dynamics (MD) simulation results for SWCNTs with various aspect (length-to-diameter) ratios and diameters will be used as the reference solutions for this assessment exercise. From MD simulations, two distinct buckling modes are observed, i.e. the shell-type buckling mode, when the aspect ratios are small, and the beam-type mode, when the aspect ratios are large. For moderate aspect ratios, the SWCNTs buckle in a mixed beam-shell mode. Therefore one chooses either the beam or the shell model depending on the aspect ratio of the carbon nanotubes (CNTs). It will be shown herein that for SWCNTs with long aspect ratios, the local Euler beam results are comparable to MD simulation results carried out at room temperature. However, when the SWCNTs have moderate aspect ratios, it is necessary to use the more refined nonlocal beam theory or the Timoshenko beam model for a better prediction of the critical strain. For short SWCNTs with large diameters, the nonlocal shell model with the appropriate small length scale parameter can provide critical strains that are in good agreement with MD results. However, for short SWCNTs with small diameters, more work has to be done to refine the nonlocal cylindrical shell model for better prediction of critical strains.

  3. Hepatitis A vaccine. A new convenient single-dose schedule with booster when long-term immunization is warranted

    DEFF Research Database (Denmark)

    Victor, J; Knudsen, J D; Nielsen, L P

    1994-01-01

    A total of 162 anti-HAV-negative healthy adults were immunized with a single high dose (1440 ELISA units = 1 ml) of inactivated hepatitis A vaccine and a booster was given at month 6. Antibodies were measured after modification of a commercial ELISA kit, enabling quantification of titres down to 6...

  4. Evaluation and validation of a single-dilution potency assay based upon serology of vaccines containing diphtheria toxoid: statistical analysis

    NARCIS (Netherlands)

    Marsman FR; Akkermans AM; Hendriksen CFM; de Jong WH

    1993-01-01

    This document presents the results of a validation study to the use of a single dilution assay in potency testing of the diphtheria component of DPT-polio vaccines. Based on historical data of multi-dilution assays on 27 consecutive batches a simulation study was performed to test the actual

  5. Vaccination of adult and newborn mice of a resistant strain (C57BL/6J) against challenge with leukemias induced by Moloney murine leukemia virus

    International Nuclear Information System (INIS)

    Reif, A.E.

    1985-01-01

    Adult or newborn C57BL/6J mice were immunized with isogenic Moloney strain MuLV-induced leukemia cells irradiated with 10,000 rads or treated with low concentrations of formalin. Groups of immunized and control mice were challenged with a range of doses of viable leukemia cells, and tumor deaths were recorded for 90 days after challenge. Then, the doses of challenge cells which produced 50% tumor deaths were calculated for immunized and control mice. The logarithm of their ratio quantified the degree of protection provided by immunization. For adult C57BL/6J mice, a single immunization with MuLV-induced leukemia cells was not effective; either cells plus Bacillus Calmette-Guerin or Corynebacterium parvum, or else two immunizations with irradiated leukemia cells were needed to produce statistically significant increases in the values of the doses of challenge cells which produced 50% tumor deaths. Cross-protection was obtained by immunization with other isogenic MuLV-induced leukemias, but not by immunization with isogenic carcinogen-induced tumors or with an isogenic spontaneous leukemia. For newborn mice, a single injection of irradiated leukemia cells provided 1.3 to 1.5 logs of protection, and admixture of B. Calmette-Guerin or C. parvum increased this protection to 2.4 to 2.7 logs. Since irradiated and frozen-thawed MuLV-induced leukemia cells contained viable MuLV, leukemia cells treated with 0.5 or 1.0% formalin were tested as an alternative. A single injection of formalin-treated isogenic leukemia cells admixed with C. parvum provided between 1.7 and 2.8 logs of protection. These results demonstrate that a single vaccination of newborn animals against a highly antigenic virally induced leukemia produces strong protection against a subsequent challenge with viable leukemia cells

  6. On the existence of minimisers for strain-gradient single-crystal plasticity

    Science.gov (United States)

    Anguige, Keith; Dondl, Patrick; Kružík, Martin

    2018-03-01

    We prove the existence of minimisers for a family of models related to the single-slip-to-single-plane relaxation of single-crystal, strain-gradient elastoplasticity with $L^p$-hardening penalty. In these relaxed models, where only one slip-plane normal can be activated at each material point, the main challenge is to show that the energy of geometrically necessary dislocations is lower-semicontinuous along bounded-energy sequences which satisfy the single-plane condition, meaning precisely that this side condition should be preserved in the weak $L^p$-limit. This is done with the aid of an 'exclusion' lemma of Conti \\& Ortiz, which essentially allows one to put a lower bound on the dislocation energy at interfaces of (single-plane) slip patches, thus precluding fine phase-mixing in the limit. Furthermore, using div-curl techniques in the spirit of Mielke \\& M\\"uller, we are able to show that the usual multiplicative decomposition of the deformation gradient into plastic and elastic parts interacts with weak convergence and the single-plane constraint in such a way as to guarantee lower-semicontinuity of the (polyconvex) elastic energy, and hence the total elasto-plastic energy, given sufficient ($p>2$) hardening, thus delivering the desired result.

  7. [Study of the correlation between the plasma viral load and protective immunity induced by the equine infectious anemia attenuated vaccine and its parental virulent strain].

    Science.gov (United States)

    Cao, Xue-Zhi; Lin, Yue-Zhi; Li, Li; Jiang, Cheng-Gang; Zhao, Li-Ping; Lv, Xiao-Ling; Zhou, Jian-Hua

    2010-03-01

    The threshold hypothesis of attenuated lentiviral vaccine considers that the type of host response to infections of lentiviruses depends on the viral load. To evaluate the correlation between viral loads of the attenuated vaccine strain of equine infectious anemia virus (EIAV) and their effects to induce protective immunity, longitudinal plasma viral loads in groups of horses inoculated with either an attenuated EIAV vaccine strain (EIAV(DLV125)) or sub-lethal dose of an EIAV virulent strain (EIAV(LN40)) were compared. Similar levels of plasma viral loads ranging from 10(3)-10(5) copies/mL were detected from samples of these two groups of animals (P > 0.05) during 23 weeks post the inoculation. However, different responses to the challenge performed thereafter with lethal dose of the EIAV virulent strain were observed from the groups of horses inoculated with either EIAV(DLV125) or sub-lethal dose of EIAV(LN40). The protective efficiency was 67% (3 of 4 cases) and 0 (none of 2 cases), respectively. Our results implicate that the viral load of EIAV attenuated vaccine is not the primary factor, or at least not the solo primary factor, to determine the establishment of immune protection.

  8. Comparison of infection-neutralizing and -enhancing antibody balance induced by two distinct genotype strains of dengue virus type 1 or 3 DNA vaccines in mice.

    Science.gov (United States)

    Sjatha, Fithriyah; Takizawa, Yamato; Kotaki, Tomohiro; Yamanaka, Atsushi; Konishi, Eiji

    2013-11-01

    Dengue viruses have spread throughout tropical and subtropical countries, and vaccine development is urgently needed. However, one concern is that induction of insufficient levels of neutralizing antibodies in vaccines may increase disease severity because of a hypothetical mechanism termed antibody-dependent enhancement of infection. This study used two distinct genotype strains of dengue virus types 1 and 3 (DENV1 and DENV3, respectively) to compare antibody responses in a mouse-DNA vaccine model. As expected, a conventional neutralization test using Vero cells showed higher antibody titers in homologous rather than heterologous combinations of genotype strains used for mouse immunization and the neutralization test, for each of DENV1 and DENV3. However, our assay system using K562 cells to measure the balance of neutralizing and enhancing antibodies indicated that Vero cell-neutralizing antibody titers did not always correlate with enhancing activities observed at subneutralizing doses. Rather, induction of enhancing activities depended on the genotype strain used for mouse immunization. The genotype/strain difference also affected IgG subclass profiles and potentially the composition of antibody species induced in mice. This study suggests that enhancing activities of dengue virus-induced neutralizing antibodies may vary according to the genotype and has implications for vaccine antigen development. Copyright © 2013 Institut Pasteur. Published by Elsevier Masson SAS. All rights reserved.

  9. Annealing effect of H+ -implanted single crystal silicon on strain and crystal structure

    International Nuclear Information System (INIS)

    Duo Xinzhong; Liu Weili; Zhang Miao; Gao Jianxia; Fu Xiaorong; Lin Chenglu

    2000-01-01

    The work focuses on the rocking curves of H + -implanted single silicon crystal detected by Four-Crystal X-ray diffractometer. The samples were annealed under different temperatures. Lattice defect in H + -implanted silicon crystals was detected by Rutherford Backscattering Spectrometry. It appeared that H-related complex did not crush until annealing temperature reached about 400 degree C. At that temperature H 2 was formed, deflated in silicon lattice and strained the lattice. But defects did not come into being in large quantity. The lattice was undamaged. When annealing temperature reached 500 degree C, strain induced by H 2 deflation crashed the silicon lattice. A large number of defects were formed. At the same time bubbles in the crystal and blister/flaking on the surface could be observed

  10. Coupled stress-strain and electrical resistivity measurements on copper based shape memory single crystals

    Directory of Open Access Journals (Sweden)

    Gonzalez Cezar Henrique

    2004-01-01

    Full Text Available Recently, electrical resistivity (ER measurements have been done during some thermomechanical tests in copper based shape memory alloys (SMA's. In this work, single crystals of Cu-based SMA's have been studied at different temperatures to analyse the relationship between stress (s and ER changes as a function of the strain (e. A good consistency between ER change values is observed in different experiments: thermal martensitic transformation, stress induced martensitic transformation and stress induced reorientation of martensite variants. During stress induced martensitic transformation (superelastic behaviour and stress induced reorientation of martensite variants, a linear relationship is obtained between ER and strain as well as the absence of hys teresis. In conclusion, the present results show a direct evidence of martensite electrical resistivity anisotropy.

  11. The strain rate effect on the buckling of single-layer MoS2.

    Science.gov (United States)

    Jiang, Jin-Wu

    2015-01-15

    The Euler buckling theory states that the buckling critical strain is an inverse quadratic function of the length for a thin plate in the static compression process. However, the suitability of this theory in the dynamical process is unclear, so we perform molecular dynamics simulations to examine the applicability of the Euler buckling theory for the fast compression of the single-layer MoS2. We find that the Euler buckling theory is not applicable in such dynamical process, as the buckling critical strain becomes a length-independent constant in the buckled system with many ripples. However, the Euler buckling theory can be resumed in the dynamical process after restricting the theory to an individual ripple in the buckled structure.

  12. T-cell factor-4 and MHC upregulation in pigs receiving a live attenuated classical swine fever virus (CSFV) vaccine strain with interferon-gamma adjuvant.

    Science.gov (United States)

    Fan, Y-H; Lin, Y-L; Hwang, Y-C; Yang, H-C; Chiu, H-C; Chiou, S-H; Jong, M-H; Chow, K-C; Lin, C-C

    2016-10-01

    The effect of co-administration of interferon (IFN)-γ in pigs undergoing vaccination with an attenuated strain (LPC) of classical swine fever virus (CSFV) was investigated. Unvaccinated pigs demonstrated pyrexia and died 7-9 days after challenge with virulent CSFV. Pigs receiving the attenuated vaccine remained healthy after virus challenge, except for mild, transient pyrexia, whereas pigs receiving IFN-γ simultaneously with the vaccine demonstrated normal body temperatures after virus challenge. Examination by nested RT-PCR revealed greater viral load in the spleens of the pigs vaccinated with the attenuated CSFV, compared with those that had additionally received IFN-γ. Expression of major histocompatibility complex (MHC) class I and MHC class II molecules was upregulated in the spleens of the IFN-γ treated vaccinated pigs, demonstrated by immunohistochemistry. Based on Western blot analysis, anti-CSFV IgG2 antibodies were elevated in vaccinated pigs by co-administration of IFN-γ (IFN-γ(Hi): P pigs that had received IFN-γ. This study suggests involvement of Tcf-4 in IFN-γ-mediated immune regulation following CSFV vaccination. Copyright © 2016 Elsevier Ltd. All rights reserved.

  13. Protective efficacy of a single immunization with capripoxvirus-vectored recombinant peste des petits ruminants vaccines in presence of pre-existing immunity.

    Science.gov (United States)

    Caufour, Philippe; Rufael, Tesfaye; Lamien, Charles Euloge; Lancelot, Renaud; Kidane, Menbere; Awel, Dino; Sertse, Tefera; Kwiatek, Olivier; Libeau, Geneviève; Sahle, Mesfin; Diallo, Adama; Albina, Emmanuel

    2014-06-24

    Sheeppox, goatpox and peste des petits ruminants (PPR) are highly contagious ruminant diseases widely distributed in Africa, the Middle East and Asia. Capripoxvirus (CPV)-vectored recombinant PPR vaccines (rCPV-PPR vaccines), which have been developed and shown to protect against both Capripox (CP) and PPR, would be critical tools in the control of these important diseases. In most parts of the world, these disease distributions overlap each other leaving concerns about the potential impact that pre-existing immunity against either disease may have on the protective efficacy of these bivalent rCPV-PPR vaccines. Currently, this question has not been indisputably addressed. Therefore, we undertook this study, under experimental conditions designed for the context of mass vaccination campaigns of small ruminants, using the two CPV recombinants (Kenya sheep-1 (KS-1) strain-based constructs) developed previously in our laboratory. Pre-existing immunity was first induced by immunization either with an attenuated CPV vaccine strain (KS-1) or the attenuated PPRV vaccine strain (Nigeria 75/1) and animals were thereafter inoculated once subcutaneously with a mixture of CPV recombinants expressing either the hemagglutinin (H) or the fusion (F) protein gene of PPRV (10(3) TCID50/animal of each). Finally, these animals were challenged with a virulent CPV strain followed by a virulent PPRV strain 3 weeks later. Our study demonstrated full protection against CP for vaccinated animals with prior exposure to PPRV and a partial protection against PPR for vaccinated animals with prior exposure to CPV. The latter animals exhibited a mild clinical form of PPR and did not show any post-challenge anamnestic neutralizing antibody response against PPRV. The implications of these results are discussed herein and suggestions made for future research regarding the development of CPV-vectored vaccines. Copyright © 2014 Elsevier Ltd. All rights reserved.

  14. The effect of vaccination with the PAV-250 strain classical swine fever (CSF) virus on the airborne transmission of CSF virus.

    Science.gov (United States)

    Gonzalez, C; Pijoan, C; Ciprian, A; Correa, P; Mendoza, S

    2001-09-01

    The airborne transmission of Classical Swine Fever (CSF) virus to susceptible pigs, as well as the effect of vaccination with the CSF virus PAV-250 strain was investigated on this mode of transmission. Experiment I: four pigs were inoculated with the ALD CSFV strain (10(4.3) 50% TCID) by the intramuscular route, and at the onset of fever, they were introduced into an enclosed chamber. At the end of the experiment surviving pigs were sedated, anesthetized and euthanatized. Experiment II: four pigs were previously vaccinated with the CSF virus PAV-250 strain, and at 14 days post-vaccination they were challenged with the CSF virus ALD strain. In both experiments, four susceptible pigs were exposed to infectious aerosols by placing them in a chamber connected by a duct to the adjacent pen containing the infected animals and were kept there for 86 hs. In Experiment I, pigs exposed to contaminated air died as a result of infection with CSF virus on days 14, 21 and 28 post-inhalation. These four pigs seroconverted from day 12 post-inhalation. CSF virus was isolated from these animals, and the fluorescent antibody test on tonsils was positive. In Experiment II, a vaccinated pig exposed to contaminated air did not seroconvert, nor was CSF virus isolated from lymphoid tissues. However, mild fluorescence in tonsil sections from these pigs was observed. In conclusion, CSF virus was shown to be transmitted by air at a distance of 1 m to susceptible pigs. Vaccination with the PAV-250 CSF virus strain protected the pigs from clinical disease under the same conditions.

  15. A single-dose antihelminthic treatment does not influence immunogenicity of a meningococcal and a cholera vaccine in Gabonese school children.

    Science.gov (United States)

    Brückner, Sina; Agnandji, Selidji Todagbe; Elias, Johannes; Berberich, Stefan; Bache, Emmanuel; Fernandes, José; Loembe, Marguerite Massinga; Hass, Johanna; Lell, Bertrand; Mordmüller, Benjamin; Adegnika, Ayola Akim; Kremsner, Peter; Esen, Meral

    2016-10-17

    We recently described the effect of a single-dose antihelminthic treatment on vaccine immunogenicity to a seasonal influenza vaccine. Here we report the effect of antihelminthics on the immunogenicity of a meningococcal vaccine and a cholera vaccine in primary school children living in Lambaréné, Gabon. Since infection with helminths remains a major public health problem and the influence on cognitive and physical development as well as the immunomodulatory effects are well established, we investigated if a single-dose antihelminthic treatment prior to immunization positively influences antibody titers and vaccine-specific memory B-cells. In this placebo-controlled, double-blind trial the effect of a single-dose antihelminthic treatment prior to immunization with a meningococcal as well as with a cholera vaccine was investigated. Anti-meningococcal antibodies were assessed by serum bactericidal assay, cholera vaccine-specific antibody titers by Enzyme-linked Immunosorbent Assay (ELISA) at baseline (Day 0; vaccination), four weeks (Day 28) and 12weeks (Day 84) following vaccination. Meningococcal and cholera vaccine-specific memory B-cells were measured at Day 0 and 84 by vaccine-specific Enzyme-linked Immunospot (ELISpot) assay. The helminth burden of the participants was assessed four weeks before vaccination (Day -28) and at Day 84 by the Merthiolate-Iodine-Formaldehyde technique. Out of 280 screened school children, 96 received a meningococcal vaccine and 89 a cholera vaccine following allocation to either the single-dose antihelminthic treatment group or the placebo group. Bactericidal antibody titers increased following immunization with the meningococcal vaccine at Day 28 and Day 84 in 68 participants for serogroup A, and in 80 participants for serogroup C. The cholera vaccine titers increased in all participants with a peak at Day 28. The number of memory B-cells increased following vaccination compared to baseline. There was no statistically significant

  16. Use of mgc2-polymerase chain reaction-restriction fragment length polymorphism for rapid differentiation between field isolates and vaccine strains of Mycoplasma gallisepticum in Israel.

    Science.gov (United States)

    Lysnyansky, Inna; Garcia, Maricarmen; Levisohn, Sharon

    2005-06-01

    Increasing use of Mycoplasma gallisepticum (MG) live vaccines has led to a need for a rapid test for differentiation of MG field strains from the live vaccine strains ts-11 and 6/85. We examined the differentiating potential of diagnostic polymerase chain reaction (PCR) primers targeted to the gene mgc2, encoding a cytadherence-related surface protein uniquely present in MG. The mgc2-PCR diagnostic primers are specific for MG in tests of all avian mycoplasmas or bacteria present in the chicken trachea and are sensitive enough to readily detect MG in tracheal swabs from field outbreaks. Differentiation of vaccine strain ts-11 was based on identification of restriction enzyme sites in the 300-base-pair (bp) mgc2-PCR amplicon present in ts-11 and missing in MG isolates from field outbreaks in Israel. Restriction sites for the enzymes HaeII and SfaN1 were identified in the amplified region in strain ts-11 and were not found in 28 field isolates of MG, comprising a representative cross section of all the MG isolates from the period 1997-2003. In practice, differential diagnosis of MG is achieved within 1 day of submission of tracheal swab samples by mgc2-PCR amplification and restriction of the amplicon with HaeII, giving a 270-bp fragment for ts-11 or no restriction for other MG strains tested. Application of the mgc2-PCR-restriction fragment length polymorphism (mgc2-PCR-RFLP) assay enabled differential diagnosis of both components of a mixture of ts-11 and non-ts-11 DNA, detecting the field strain in the presence of a large excess of ts-11. The test was successfully applied in vivo for monitoring vaccinates in a ts-11 vaccine trial. In principle, the test may also be used to identify the 6/85 vaccine strain, which yields a 237-bp product, readily differentiated from the approximately 300-bp PCR product of all other strains tested. Further testing of field isolates will be necessary to determine the applicability of this test in the United States and other countries.

  17. Quality of broilers infected with autochthonous MGA strain, alone or in combination with Infectious Bronchitis Virus (IBV vaccine

    Directory of Open Access Journals (Sweden)

    Cátia Cardoso da Silva

    2016-12-01

    Full Text Available ABSTRACT. da Silva C.C., dos Santos F.F., Faria T.S., José D.S., Tortelly R., Abreu D.L. da C., do Nascimento E.R., Machado L. dos S., Soares M.V. & Pereira V.L.A. [Quality of broilers infected with autochthonous MGA strain, alone or in combination with Infectious Bronchitis Virus (IBV vaccine.] Qualidade de frangos de corte infectados com Mycoplasma gallinarum isoladamente ou em combinação com o vírus vacinal da Bronquite Infecciosa das Galinhas. Revista Brasileira de Medicina Veterinária, 38(4:420-430, 2016. Departamento de Saúde Coletiva, Faculdade de Veterinária, Universidade Federal Fluminense, Rua Vital Brazil Filho, 64, Niterói, RJ 24230-340, Brasil. E-mail: catinha_cardoso@hotmail.com Brazil is the world’s largest exporter and third largest producer of poultry meat. Advances in management, biosecurity and genetics have contributed to the increase in productivity of the poultry industry, at the same time the pronounced production increased the risk of spreading respiratory diseases, such as avian mycoplasmosis and Infectious Bronchitis. Mycoplasma gallisepticum (MG, Mycoplasma synoviae (MS and Mycoplasma meleagridis (MM are recognized as indisputable pathogens for the poultry industry, however Mycoplasma gallinarum (MGA has been considered commensal. The aim of this study was to evaluate the quality of broilers infected with autochthonous MGA strain, alone or in combination with Infectious Bronchitis Virus (IBV vaccine. There were raised 96 broiler chicks since one-day-old, Cobb line, mycoplasma free. They were separated in four groups of 24 birds kept in isolation units: Group 1 (G1, uninfected and unvaccinated; Group 2 (G2, infected with autochthonous MGA strain; Group 3 (G3, vaccinated with commercial IBV strain H120 (Bio-bronk-vet ®, Biovet, SP; Group 4 (G4, infected with MGA and vaccinated with commercial IBV. The infection was monitored by MGA PCR and IBV vaccination was confirmed by RT-PCR. The feed intake record was

  18. 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

  19. Mononuclear Clusterfullerene Single-Molecule Magnet Containing Strained Fused-Pentagons Stabilized by a Nearly Linear Metal Cyanide Cluster

    DEFF Research Database (Denmark)

    Liu, Fupin; Wang, Song; Gao, Cong Li

    2017-01-01

    Fused-pentagons results in an increase of local steric strain according to the isolated pentagon rule (IPR), and for all reported non-IPR clusterfullerenes multiple (two or three) metals are required to stabilize the strained fused-pentagons, making it difficult to access the single-atom properti...... (SMM)....

  20. Highly Predictive Model for a Protective Immune Response to the A(H1N1pdm2009 Influenza Strain after Seasonal Vaccination.

    Directory of Open Access Journals (Sweden)

    Karsten Jürchott

    Full Text Available Understanding the immune response after vaccination against new influenza strains is highly important in case of an imminent influenza pandemic and for optimization of seasonal vaccination strategies in high risk population groups, especially the elderly. Models predicting the best sero-conversion response among the three strains in the seasonal vaccine were recently suggested. However, these models use a large number of variables and/or information post- vaccination. Here in an exploratory pilot study, we analyzed the baseline immune status in young (<31 years, N = 17 versus elderly (≥50 years, N = 20 donors sero-negative to the newly emerged A(H1N1pdm09 influenza virus strain and correlated it with the serological response to that specific strain after seasonal influenza vaccination. Extensive multi-chromatic FACS analysis (36 lymphocyte sub-populations measured was used to quantitatively assess the cellular immune status before vaccination. We identified CD4+ T cells, and amongst them particularly naive CD4+ T cells, as the best correlates for a successful A(H1N1pdm09 immune response. Moreover, the number of influenza strains a donor was sero-negative to at baseline (NSSN in addition to age, as expected, were important predictive factors. Age, NSSN and CD4+ T cell count at baseline together predicted sero-protection (HAI≥40 to A(H1N1pdm09 with a high accuracy of 89% (p-value = 0.00002. An additional validation study (N = 43 vaccinees sero-negative to A(H1N1pdm09 has confirmed the predictive value of age, NSSN and baseline CD4+ counts (accuracy = 85%, p-value = 0.0000004. Furthermore, the inclusion of donors at ages 31-50 had shown that the age predictive function is not linear with age but rather a sigmoid with a midpoint at about 50 years. Using these results we suggest a clinically relevant prediction model that gives the probability for non-protection to A(H1N1pdm09 influenza strain after seasonal multi-valent vaccination as a

  1. Engineering Enhanced Vaccine Cell Lines To Eradicate Vaccine-Preventable Diseases: the Polio End Game.

    Science.gov (United States)

    van der Sanden, Sabine M G; Wu, Weilin; Dybdahl-Sissoko, Naomi; Weldon, William C; Brooks, Paula; O'Donnell, Jason; Jones, Les P; Brown, Cedric; Tompkins, S Mark; Oberste, M Steven; Karpilow, Jon; Tripp, Ralph A

    2016-02-15

    Vaccine manufacturing costs prevent a significant portion of the world's population from accessing protection from vaccine-preventable diseases. To enhance vaccine production at reduced costs, a genome-wide RNA interference (RNAi) screen was performed to identify gene knockdown events that enhanced poliovirus replication. Primary screen hits were validated in a Vero vaccine manufacturing cell line using attenuated and wild-type poliovirus strains. Multiple single and dual gene silencing events increased poliovirus titers >20-fold and >50-fold, respectively. Host gene knockdown events did not affect virus antigenicity, and clustered regularly interspaced short palindromic repeat (CRISPR)-Cas9-mediated knockout of the top candidates dramatically improved viral vaccine strain production. Interestingly, silencing of several genes that enhanced poliovirus replication also enhanced replication of enterovirus 71, a clinically relevant virus to which vaccines are being targeted. The discovery that host gene modulation can markedly increase virus vaccine production dramatically alters mammalian cell-based vaccine manufacturing possibilities and should facilitate polio eradication using the inactivated poliovirus vaccine. Using a genome-wide RNAi screen, a collection of host virus resistance genes was identified that, upon silencing, increased poliovirus and enterovirus 71 production by from 10-fold to >50-fold in a Vero vaccine manufacturing cell line. This report provides novel insights into enterovirus-host interactions and describes an approach to developing the next generation of vaccine manufacturing through engineered vaccine cell lines. The results show that specific gene silencing and knockout events can enhance viral titers of both attenuated (Sabin strain) and wild-type polioviruses, a finding that should greatly facilitate global implementation of inactivated polio vaccine as well as further reduce costs for live-attenuated oral polio vaccines. This work

  2. Infection with equine infectious anemia virus vaccine strain EIAVDLV121 causes no visible histopathological lesions in target organs in association with restricted viral replication and unique cytokine response.

    Science.gov (United States)

    Liu, Qiang; Ma, Jian; Wang, Xue-Feng; Xiao, Fei; Li, Li-Jia; Zhang, Jiao-Er; Lin, Yue-Zhi; Du, Cheng; He, Xi-Jun; Wang, Xiaojun; Zhou, Jian-Hua

    2016-02-01

    The live equine infectious anemia virus (EIAV) vaccine strain EIAVDLV121 was developed by in vitro attenuation of a virulent strain, EIAVLN40, in the 1970s, and it has been demonstrated to induce protective immunity under laboratory and natural EIAV infection conditions. The detailed biological features of this attenuated virus remain to be further investigated. Experimental inoculation with EIAVDLV121 did not result in clinical symptoms even with immunosuppressive treatment in our previous studies. Here, we further investigated whether the replication of the vaccine strain EIAVDLV121 in experimentally infected horses causes histopathological lesions to develop in the targeted organs. Both the lungs and the spleen have been demonstrated to support EIAV replication. By evaluating the gross macroscopic and histological changes, we found that EIAVDLV121 did not cause detectable histopathological lesions and that it replicated several hundred times more slowly than its parental virulent strain, EIAVLN40, in tissues. Immunochemical assays of these tissues indicated that the primary target cells of EIAVDLV121 were monocytes/macrophages, but that EIAVLN40 also infected alveolar epithelial cells and vascular endothelial cells. In addition, both of these viral strains promoted the up- and down-regulation of the expression of various cytokines and chemokines, implicating the potential involvement of these cellular factors in the pathological outcomes of EIAV infection and host immune responses. Taken together, these results demonstrate that the EIAV vaccine strain does not cause obvious histopathological lesions or clinical symptoms and that it induces a unique cytokine response profile. These features are considered essential for EIAVDLV121 to function as an effective live vaccine. Copyright © 2016 Elsevier B.V. All rights reserved.

  3. 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...

  4. DeltaguaBA attenuated Shigella flexneri 2a strain CVD 1204 as a Shigella vaccine and as a live mucosal delivery system for fragment C of tetanus toxin.

    Science.gov (United States)

    Anderson, R J; Pasetti, M F; Sztein, M B; Levine, M M; Noriega, F R

    2000-04-28

    The DeltaguaBA Shigella flexneri 2a vaccine candidate, CVD 1204, was evaluated as a delivery system for the non-toxic C-terminal of tetanus toxin (fragment C), either as a polypeptide expressed in the bacteria or as a DNA vaccine. CVD 1204 was transformed with plasmid pTETnir15 which encodes the fragment C gene (tetC) under the control of the inducible prokaryotic nir15 promoter or a DNA vaccine plasmid pcDNA3tetC which encodes tetC under the eukaryotic hCMV promoter. Guinea pigs immunised intranasally (i.n.) with either recombinant strain mounted a secretory immune response against S. flexneri 2a Lipopolysaccharide (LPS) and were protected against ocular challenge with wild-type S. flexneri 2a. Both strains were effective in eliciting a serum IgG response against fragment C in guinea pigs following i.n. immunisation. Furthermore, serum from guinea pigs immunised with CVD 1204(pTETnir15) contained tetanus toxin neutralising antibodies. These results demonstrate that this S. flexneri 2a vaccine candidate can serve as a vehicle for the delivery of foreign antigens to the systemic immune system while retaining its capacity to serve as a mucosal Shigella vaccine.

  5. The patterns of in vitro cell-death and inflammatory cytokines induced by distinct BCG vaccine strains are differentially induced in human mononuclear cells.

    Science.gov (United States)

    Ponte, C; Hacker, M; Moraes, M; Castello-Branco, L; Silva, F; Antas, P

    2018-01-02

    Tuberculosis (TB) remains among the world's leading cause of mortality. For its control, studies of TB vaccines are needed. Since live-attenuated Mycobacterium bovis bacillus Calmette-Guérin (BCG) is the only TB vaccine currently in use, studies on the protective role of BCG are required. In this study, we analyzed host cells purified directly from whole blood of human immunodeficiency virus (HIV)-negative volunteers, comprising adult healthy donors (HD) and neonates (umbilical cord bloods, UCB), with the aim to directly compare in vitro immune responses with distinct BCG strains in human mononuclear cells. The Moreau, Pasteur, and Danish BCG strains were used to infect mononuclear cells in vitro for 48 h; bacilli viability and cell-death were subsequently detected by flow cytometry. In addition, cell culture supernatants were used in cytokine detection assays. Overall, the Moreau BCG strain induced higher levels of apoptosis than the Pasteur and Danish BCG strains in both the HD and UCB groups (p-value BCG infection. The Moreau BCG strain, exclusively, induced Th1 cytokines at the highest levels in cells from adults (p-value BCG strains, whereas TGF-β1 levels were reduced significantly (p-value BCG vaccine. As expected, eight out of 22 pro-inflammatory cytokines were secreted at significant levels (p-value BCG-infected cell cultures, in the HD group only. When analyzing these results, we excluded confounding factors related to storage and viability of the BCG strains used. These findings suggest that Moreau BCG is a more potent immunostimulating agent than the Pasteur and Danish BCG strains. Clinical trials will be needed to confirm these findings.

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

    Science.gov (United States)

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

    2013-02-04

    DNA vaccines combine remarkable genetic and chemical stability with proven safety and efficacy in animal models, while remaining less immunogenic in humans. In contrast, live-attenuated vaccines have the advantage of inducing rapid, robust, long-term immunity after a single-dose vaccination. Here we describe novel iDNA vaccine technology that is based on an infectious DNA platform and combines advantages of DNA and live attenuated vaccines. We applied this technology for vaccination against infection with Venezuelan equine encephalitis virus (VEEV), an alphavirus from the Togaviridae family. The iDNA vaccine is based on transcription of the full-length genomic RNA of the TC-83 live-attenuated virus from plasmid DNA in vivo. The in vivo-generated viral RNA initiates limited replication of the vaccine virus, which in turn leads to efficient immunization. This technology allows the plasmid DNA to launch a live-attenuated vaccine in vitro or in vivo. Less than 10 ng of pTC83 iDNA encoding the full-length genomic RNA of the TC-83 vaccine strain initiated replication of the vaccine virus in vitro. In order to evaluate this approach in vivo, BALB/c mice were vaccinated with a single dose of pTC83 iDNA. After vaccination, all mice seroconverted with no adverse reactions. Four weeks after immunization, animals were challenged with the lethal epidemic strain of VEEV. All iDNA-vaccinated mice were protected from fatal disease, while all unvaccinated controls succumbed to infection and died. To our knowledge, this is the first example of launching a clinical live-attenuated vaccine from recombinant plasmid DNA in vivo. Copyright © 2012 Elsevier Ltd. All rights reserved.

  7. Comparative efficacy of an indigenous 'inactivated vaccine' using highly pathogenic field strain of Mycobacterium avium subspecies paratuberculosis 'Bison type' with a commercial vaccine for the control of Capri-paratuberculosis in India.

    Science.gov (United States)

    Singh, S V; Singh, P K; Singh, A V; Sohal, J S; Gupta, V K; Vihan, V S

    2007-10-10

    Johne's disease (JD) is endemic in goatherds located at Central Institute for Research on Goats, Makhdoom, since 1979 and lately it has been reported from farmer's herds in equal frequencies. Despite using test and slaughter method for the control of JD for more than 25 years in these herds, incidence of JD has not been reduced. Efficacy of 'indigenous vaccine' containing native 'Bison type' genotype of Mycobacterium avium subspecies paratuberculosis (MAP) was compared with commercial vaccine using challenge studies with homologous strain of MAP. Goat kids (85) were randomly divided in to three groups. Kids were vaccinated with 1 ml of vaccine subcutaneously and Sham-immunized with 1 ml of sterile PBS. All kids except 3 in each group were challenged twice at 75- and 275-day post-vaccination (DPV). Four goats each from three groups were sacrificed at 200-day post-challenge to evaluate carcass and histopathologically for vaccine and challenge response in kids of different groups. Samples (blood, serum and fecal) were screened for LTT, ELISA and shedding of bacilli and data on live animal traits, mortality and experimental sacrifice were compared. Average body weights gained by goats in three groups at different stages of trials (0, 1-75, 76-275, 276-425 DPV) showed marked improvements in performance of vaccinated groups over 'Sham-immunized' group. Effect of vaccines against challenge became visible in terms of body weights gained at 276-425 DPV ('Bison' group gained significantly higher body weights than 'Sham-immunized'). Mortality was significantly less in two vaccinated as compared to 'Sham-immunized'. Vaccinated groups also had significant stimulation and sero-conversion for cell mediated and humoral immune response, respectively as compared to 'Sham-immunized'. Results of post-challenged fecal culture showed significant reduction in shedding of MAP in both vaccinated groups than in 'Sham-immunized'. There was significant improvement in external and internal

  8. Efficacy and safety of simultaneous vaccination with two modified live virus vaccines against porcine reproductive and respiratory syndrome virus types 1 and 2 in pigs

    DEFF Research Database (Denmark)

    Kristensen, Charlotte S.; Kvisgaard, Lise Kirstine; Pawlowski, Maciej

    2018-01-01

    there was limited effect on the viral load in serum following challenge with the PRRSV-1 strains. Vaccination against PRRSV-1 had less impact on viremia following challenge. The protective effects of simultaneous vaccination with PRRSV Type 1 and 2 MLV vaccines and single PRRS MLV vaccination were comparable. None....... Thus, simultaneous administration of the two vaccines is an option in herds with both PRRSV types.......The objective of the study was to compare responses of pigs vaccinated with a PRRS MLV vaccine against PRRSV-1 or PRRSV-2 with the responses of pigs vaccinated simultaneously with both vaccines. Furthermore, the efficacy of the two PRRSV MLV vaccination strategies was assessed following challenge...

  9. Pre-Clinical Development of BCG.HIVACAT, an Antibiotic-Free Selection Strain, for HIV-TB Pediatric Vaccine Vectored by Lysine Auxotroph of BCG

    Science.gov (United States)

    Saubi, Narcís; Mbewe-Mvula, Alice; Gea-Mallorqui, Ester; Rosario, Maximillian; Gatell, Josep Maria; Hanke, Tomáš; Joseph, Joan

    2012-01-01

    In the past, we proposed to develop a heterologous recombinant BCG prime-recombinant modified vaccinia virus Ankara (MVA) boost dual pediatric vaccine platform against transmission of breast milk HIV-1 and Mycobacterium tuberculosis (Mtb). In this study, we assembled an E. coli-mycobacterial shuttle plasmid pJH222.HIVACAT expressing HIV-1 clade A immunogen HIVA. This shuttle vector employs an antibiotic resistance-free mechanism based on Operator-Repressor Titration (ORT) system for plasmid selection and maintenance in E. coli and lysine complementation in mycobacteria. This shuttle plasmid was electroporated into parental lysine auxotroph (safer) strain of BCG to generate vaccine BCG.HIVACAT. All procedures complied with Good Laboratory Practices (GLPs). We demonstrated that the episomal plasmid pJH222.HIVACAT was stable in vivo over a 20-week period, and genetically and phenotypically characterized the BCG.HIVACAT vaccine strain. The BCG.HIVACAT vaccine in combination with MVA.HIVA induced HIV-1- and Mtb-specific interferon γ-producing T-cell responses in newborn and adult BALB/c mice. On the other hand, when adult mice were primed with BCG.HIVACAT and boosted with MVA.HIVA.85A, HIV-1-specific CD8+ T-cells producing IFN-γ, TNF-α, IL-2 and CD107a were induced. To assess the biosafety profile of BCG.HIVACAT-MVA.HIVA regimen, body mass loss of newborn mice was monitored regularly throughout the vaccination experiment and no difference was observed between the vaccinated and naïve groups of animals. Thus, we demonstrated T-cell immunogenicity of a novel, safer, GLP-compatible BCG-vectored vaccine using prototype immunogen HIVA. Second generation immunogens derived from HIV-1 as well as other major pediatric pathogens can be constructed in a similar fashion to prime protective responses soon after birth. PMID:22927933

  10. African horse sickness virus (AHSV) with a deletion of 77 amino acids in NS3/NS3a protein is not virulent and a safe promising AHS Disabled Infectious Single Animal (DISA) vaccine platform.

    Science.gov (United States)

    van Rijn, Piet A; Maris-Veldhuis, Mieke A; Potgieter, Christiaan A; van Gennip, René G P

    2018-04-05

    African horse sickness virus (AHSV) is a virus species in the genus Orbivirus of the family Reoviridae. Currently, nine serotypes have been defined showing limited cross neutralization. AHSV is transmitted by species of Culicoides biting midges and causes African Horse Sickness (AHS) in equids with a mortality up to 95% in naïve domestic horses. AHS has become a serious threat for countries outside Africa, since endemic Culicoides species in moderate climates are competent vectors of closely related bluetongue virus. AHS outbreaks cause huge economic losses in developing countries. In the developed world, outbreaks will result in losses in the equestrian industry and will have an enormous emotional impact on owners of pet horses. Live-attenuated vaccine viruses (LAVs) have been developed, however, safety of these LAVs are questionable due to residual virulence, reversion to virulence, and risk on virulent variants by reassortment between LAVs or with field AHSV. Research aims vaccines with improved profiles. Reverse genetics has recently being developed for AHSV and has opened endless possibilities including development of AHS vaccine candidates, such as Disabled Infectious Single Animal (DISA) vaccine. Here, virulent AHSV5 was recovered and its high virulence was confirmed by experimental infection of ponies. 'Synthetically derived' virulent AHSV5 with an in-frame deletion of 77 amino acids codons in genome segment 10 encoding NS3/NS3a protein resulted in similar in vitro characteristics as published NS3/NS3a knockout mutants of LAV strain AHSV4LP. In contrast to its highly virulent ancestor virus, this deletion AHSV5 mutant (DISA5) was completely safe for ponies. Two vaccinations with DISA5 as well as two vaccinations with DISA vaccine based on LAV strain AHSV4LP showed protection against lethal homologous AHSV. More research is needed to further improve efficacy, to explore the AHS DISA vaccine platform for all nine serotypes, and to study the vaccine profile

  11. 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

  12. Construction of a recombinant duck enteritis virus (DEV) expressing hemagglutinin of H5N1 avian influenza virus based on an infectious clone of DEV vaccine strain and evaluation of its efficacy in ducks and chickens

    OpenAIRE

    Wang, Jichun; Ge, Aimin; Xu, Mengwei; Wang, Zhisheng; Qiao, Yongfeng; Gu, Yiqi; Liu, Chang; Liu, Yamei; Hou, Jibo

    2015-01-01

    Background Highly pathogenic avian influenza virus (AIV) subtype H5N1 remains a threat to poultry. Duck enteritis virus (DEV)-vectored vaccines expressing AIV H5N1 hemagglutinin (HA) may be viable AIV and DEV vaccine candidates. Methods To facilitate the generation and further improvement of DEV-vectored HA(H5) vaccines, we first constructed an infectious clone of DEV Chinese vaccine strain C-KCE (DEVC-KCE). Then, we generated a DEV-vectored HA(H5) vaccine (DEV-H5(UL55)) based on the bacteria...

  13. Fallacy of the Unique Genome: Sequence Diversity within Single Helicobacter pylori Strains

    Directory of Open Access Journals (Sweden)

    Jenny L. Draper

    2017-02-01

    Full Text Available Many bacterial genomes are highly variable but nonetheless are typically published as a single assembled genome. Experiments tracking bacterial genome evolution have not looked at the variation present at a given point in time. Here, we analyzed the mouse-passaged Helicobacter pylori strain SS1 and its parent PMSS1 to assess intra- and intergenomic variability. Using high sequence coverage depth and experimental validation, we detected extensive genome plasticity within these H. pylori isolates, including movement of the transposable element IS607, large and small inversions, multiple single nucleotide polymorphisms, and variation in cagA copy number. The cagA gene was found as 1 to 4 tandem copies located off the cag island in both SS1 and PMSS1; this copy number variation correlated with protein expression. To gain insight into the changes that occurred during mouse adaptation, we also compared SS1 and PMSS1 and observed 46 differences that were distinct from the within-genome variation. The most substantial was an insertion in cagY, which encodes a protein required for a type IV secretion system function. We detected modifications in genes coding for two proteins known to affect mouse colonization, the HpaA neuraminyllactose-binding protein and the FutB α-1,3 lipopolysaccharide (LPS fucosyltransferase, as well as genes predicted to modulate diverse properties. In sum, our work suggests that data from consensus genome assemblies from single colonies may be misleading by failing to represent the variability present. Furthermore, we show that high-depth genomic sequencing data of a population can be analyzed to gain insight into the normal variation within bacterial strains.

  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. Vaccine platform recombinant measles virus.

    Science.gov (United States)

    Mühlebach, Michael D

    2017-10-01

    The classic development of vaccines is lengthy, tedious, and may not necessarily be successful as demonstrated by the case of HIV. This is especially a problem for emerging pathogens that are newly introduced into the human population and carry the inherent risk of pandemic spread in a naïve population. For such situations, a considerable number of different platform technologies are under development. These are also under development for pathogens, where directly derived vaccines are regarded as too complicated or even dangerous due to the induction of inefficient or unwanted immune responses causing considerable side-effects as for dengue virus. Among platform technologies are plasmid-based DNA vaccines, RNA replicons, single-round infectious vector particles, or replicating vaccine-based vectors encoding (a) critical antigen(s) of the target pathogens. Among the latter, recombinant measles viruses derived from vaccine strains have been tested. Measles vaccines are among the most effective and safest life-attenuated vaccines known. Therefore, the development of Schwarz-, Moraten-, or AIK-C-strain derived recombinant vaccines against a wide range of mostly viral, but also bacterial pathogens was quite straightforward. These vaccines generally induce powerful humoral and cellular immune responses in appropriate animal models, i.e., transgenic mice or non-human primates. Also in the recent first clinical phase I trial, the results have been quite encouraging. The trial indicated the expected safety and efficacy also in human patients, interestingly independent from the level of prevalent anti-measles immunity before the trial. Thereby, recombinant measles vaccines expressing additional antigens are a promising platform for future vaccines.

  16. Single-dose vaccines save livestock and livelihoods in Sub-Saharan ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Livestock production is a critical industry in Africa, but suffers large losses to preventable viral infections. This project aims to curb the problem. Researchers will fine-tune prototype vaccines, conduct field tests, and take the first steps to commercializing new vaccines. Africa's livestock industry The research will take place in ...

  17. Vaccination coverage and mortality after splenectomy: results from an Italian single-centre study.

    Science.gov (United States)

    Di Sabatino, Antonio; Lenti, Marco Vincenzo; Tinozzi, Francesco Paolo; Lanave, Marina; Aquino, Ivana; Klersy, Catherine; Marone, Piero; Marena, Carlo; Pietrabissa, Andrea; Corazza, Gino Roberto

    2017-12-01

    Splenectomy is a well-recognised risk factor for life-threatening overwhelming post-splenectomy infection (OPSI). To prevent OPSI, immunisations against encapsulated bacteria (S. pneumoniae, N. meningitidis, H. influenzae) and influenza virus are recommended. However, there is still a lack of uniformity and poor compliance with these recommendations. Following a local physicians' awareness campaign regarding the importance of vaccine prophylaxis of splenectomised patients, we aimed to register vaccination coverage, mortality and infection rates in all patients who underwent splenectomy at our hospital, over a six-year time span. Reasons for splenectomy, patients' compliance with vaccinations, mortality and infectious events were recorded. The reasons for splenectomy in the 216 identified patients (mean age 58.2 ± 14; M:F ratio 1.4:1) were haematologic disorders (38.8%), solid tumours (28.7%), traumatic rupture (22.7%) and other causes (9.7%). A total of 146 patients (67.6%) received at least one of the four vaccines. Overall, the mortality rate was significantly greater in unvaccinated compared to vaccinated patients (p splenectomy the statistical significance was lost (p = 0.085) due to the burden of solid tumour-related mortality. Among the 21 reported cases of OPSI, eight were fatal and five were potentially vaccine-preventable. Our results show that two-thirds of splenectomised patients comply with vaccine prophylaxis. Future interventional studies or ad hoc registries might overcome barriers to vaccination or intentional non-compliance.

  18. Longitudinal multiparameter single-cell analysis of macaques immunized with pneumococcal protein-conjugated or unconjugated polysaccharide vaccines reveals distinct antigen specific memory B cell repertoires.

    Directory of Open Access Journals (Sweden)

    Bin Jia

    Full Text Available The efficacy of protein-conjugated pneumococcal polysaccharide vaccines has been well characterized for children. The level of protection conferred by unconjugated polysaccharide vaccines remains less clear, particularly for elderly individuals who have had prior antigenic experience through immunization with unconjugated polysaccharide vaccines or natural exposure to Streptococcus pneumoniae.We compared the magnitude, diversity and genetic biases of antigen-specific memory B cells in two groups of adult cynomolgus macaques that were immunized with a 7-valent conjugated vaccine and boosted after five years with either a 13-valent pneumococcal polysaccharide conjugate vaccine (13vPnC or a 23-valent unconjugated pneumococcal polysaccharide vaccine (23vPS using microengraving (a single-cell analysis method and single-cell RT-PCR.Seven days after boosting, the mean frequency of antigen-specific memory B cells was significantly increased in macaques vaccinated with 13vPnC compared to those receiving 23vPS. The 13vPnC-vaccinated macaques also exhibited a more even distribution of antibody specificities to four polysaccharides in the vaccine (PS4, 6B, 14, 23F that were examined. However, single-cell analysis of the antibody variable region sequences from antigen-specific B cells elicited by unconjugated and conjugated vaccines indicated that both the germline gene segments forming the heavy chains and the average lengths of the Complementary Determining Region 3 (CDR3 were similar.Our results confirm that distinctive differences can manifest between antigen-specific memory B cell repertoires in nonhuman primates immunized with conjugated and unconjugated pneumococcal polysaccharide vaccines. The study also supports the notion that the conjugated vaccines have a favorable profile in terms of both the frequency and breadth of the anamnestic response among antigen-specific memory B cells.

  19. Longitudinal multiparameter single-cell analysis of macaques immunized with pneumococcal protein-conjugated or unconjugated polysaccharide vaccines reveals distinct antigen specific memory B cell repertoires.

    Science.gov (United States)

    Jia, Bin; McNeil, Lisa K; Dupont, Christopher D; Tsioris, Konstantinos; Barry, Rachel M; Scully, Ingrid L; Ogunniyi, Adebola O; Gonzalez, Christopher; Pride, Michael W; Gierahn, Todd M; Liberator, Paul A; Jansen, Kathrin U; Love, J Christopher

    2017-01-01

    The efficacy of protein-conjugated pneumococcal polysaccharide vaccines has been well characterized for children. The level of protection conferred by unconjugated polysaccharide vaccines remains less clear, particularly for elderly individuals who have had prior antigenic experience through immunization with unconjugated polysaccharide vaccines or natural exposure to Streptococcus pneumoniae. We compared the magnitude, diversity and genetic biases of antigen-specific memory B cells in two groups of adult cynomolgus macaques that were immunized with a 7-valent conjugated vaccine and boosted after five years with either a 13-valent pneumococcal polysaccharide conjugate vaccine (13vPnC) or a 23-valent unconjugated pneumococcal polysaccharide vaccine (23vPS) using microengraving (a single-cell analysis method) and single-cell RT-PCR. Seven days after boosting, the mean frequency of antigen-specific memory B cells was significantly increased in macaques vaccinated with 13vPnC compared to those receiving 23vPS. The 13vPnC-vaccinated macaques also exhibited a more even distribution of antibody specificities to four polysaccharides in the vaccine (PS4, 6B, 14, 23F) that were examined. However, single-cell analysis of the antibody variable region sequences from antigen-specific B cells elicited by unconjugated and conjugated vaccines indicated that both the germline gene segments forming the heavy chains and the average lengths of the Complementary Determining Region 3 (CDR3) were similar. Our results confirm that distinctive differences can manifest between antigen-specific memory B cell repertoires in nonhuman primates immunized with conjugated and unconjugated pneumococcal polysaccharide vaccines. The study also supports the notion that the conjugated vaccines have a favorable profile in terms of both the frequency and breadth of the anamnestic response among antigen-specific memory B cells.

  20. Design and statistical considerations for studies evaluating the efficacy of a single dose of the human papillomavirus (HPV) vaccine.

    Science.gov (United States)

    Sampson, Joshua N; Hildesheim, Allan; Herrero, Rolando; Gonzalez, Paula; Kreimer, Aimee R; Gail, Mitchell H

    2018-05-01

    Cervical cancer is a leading cause of cancer mortality in women worldwide. Human papillomavirus (HPV) types 16 and 18 cause about 70% of all cervical cancers. Clinical trials have demonstrated that three doses of either commercially available HPV vaccine, Cervarix ® or Gardasil ®, prevent most new HPV 16/18 infections and associated precancerous lesions. Based on evidence of immunological non-inferiority, 2-dose regimens have been licensed for adolescents in the United States, European Union, and elsewhere. However, if a single dose were effective, vaccine costs would be reduced substantially and the logistics of vaccination would be greatly simplified, enabling vaccination programs in developing countries. The National Cancer Institute (NCI) and the Agencia Costarricense de Investigaciones Biomédicas (ACIB) are conducting, with support from the Bill & Melinda Gates Foundation and the International Agency for Research on Cancer (IARC), a large 24,000 girl study to evaluate the efficacy of a 1-dose regimen. The first component of the study is a four-year non-inferiority trial comparing 1- to 2-dose regimens of the two licensed vaccines. The second component is an observational study that estimates the vaccine efficacy (VE) of each regimen by comparing the HPV infection rates in the trial arms to those in a contemporaneous survey group of unvaccinated girls. In this paper, we describe the design and statistical analysis for this study. We explain the advantage of defining non-inferiority on the absolute risk scale when the expected event rate is near 0 and, given this definition, suggest an approach to account for missing clinic visits. We then describe the problem of estimating VE in the absence of a randomized placebo arm and offer our solution. Copyright © 2018. Published by Elsevier Inc.

  1. 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...

  2. Strain gradient crystal plasticity analysis of a single crystal containing a cylindrical void

    DEFF Research Database (Denmark)

    Borg, Ulrik; Kysar, J.W.

    2007-01-01

    The effects of void size and hardening in a hexagonal close-packed single crystal containing a cylindrical void loaded by a far-field equibiaxial tensile stress under plane strain conditions are studied. The crystal has three in-plane slip systems oriented at the angle 60 degrees with respect...... plasticity formulation. The stress and deformation fields obtained with a local non-hardening constitutive formulation are compared to those obtained from a local hardening formulation and to those from a non-local formulation. Compared to the case of the non-hardening local constitutive formulation......, it is shown that a local theory with hardening has only minor effects on the deformation field around the void, whereas a significant difference is obtained with the non-local constitutive relation. Finally, it is shown that the applied stress state required to activate plastic deformation at the void is up...

  3. Strain-gradient-induced polarization in SrTiO3 single crystals.

    Science.gov (United States)

    Zubko, P; Catalan, G; Buckley, A; Welche, P R L; Scott, J F

    2007-10-19

    Piezoelectricity is inherent only in noncentrosymmetric materials, but a piezoelectric response can also be obtained in centrosymmetric crystals if subjected to inhomogeneous deformation. This phenomenon, known as flexoelectricity, can significantly affect the functional properties of insulators, particularly thin films of high permittivity materials. We have measured strain-gradient-induced polarization in single crystals of paraelectric SrTiO3 as a function of temperature and orientation down to and below the 105 K phase transition. Estimates were obtained for all the components of the flexoelectric tensor, and calculations based on these indicate that local polarization around defects in SrTiO3 may exceed the largest ferroelectric polarizations. A sign reversal of the flexoelectric response detected below the phase transition suggests that the ferroelastic domain walls of SrTiO3 may be polar.

  4. Strain-Gradient-Induced Polarization in SrTiO3 Single Crystals

    Science.gov (United States)

    Zubko, P.; Catalan, G.; Buckley, A.; Welche, P. R. L.; Scott, J. F.

    2007-10-01

    Piezoelectricity is inherent only in noncentrosymmetric materials, but a piezoelectric response can also be obtained in centrosymmetric crystals if subjected to inhomogeneous deformation. This phenomenon, known as flexoelectricity, can significantly affect the functional properties of insulators, particularly thin films of high permittivity materials. We have measured strain-gradient-induced polarization in single crystals of paraelectric SrTiO3 as a function of temperature and orientation down to and below the 105 K phase transition. Estimates were obtained for all the components of the flexoelectric tensor, and calculations based on these indicate that local polarization around defects in SrTiO3 may exceed the largest ferroelectric polarizations. A sign reversal of the flexoelectric response detected below the phase transition suggests that the ferroelastic domain walls of SrTiO3 may be polar.

  5. Detection of Brucella melitensis and Brucella abortus strains using a single-stage PCR method

    Directory of Open Access Journals (Sweden)

    Alamian, S.

    2015-04-01

    Full Text Available Brucella melitensis and Brucella abortus are of the most important causes of brucellosis, an infectious disease which is transmitted either directly or indirectly including consuming unpasteurized dairy products. Both strains are considered endemic in Iran. Common diagnostic methods such as bacteriologic cultures are difficult and time consuming regarding the bacteria. The aim of this study was to suggest a single-stage PCR method using a pair of primers to detect both B. melitensis and B. abortus. The primers were named UF1 and UR1 and the results showed that the final size of PCR products were 84 bp and 99 bp for B. melitensis and B. abortus, respectively. Therefore the method could be useful for rapid detection of B. melitensis and B. abortus simultaneously.

  6. Universal influenza vaccines, science fiction or soon reality?

    NARCIS (Netherlands)

    R.D. de Vries (Rory); A.F. Altenburg (Arwen); G.F. Rimmelzwaan (Guus)

    2015-01-01

    textabstractCurrently used influenza vaccines are only effective when the vaccine strains match the epidemic strains antigenically. To this end, seasonal influenza vaccines must be updated almost annually. Furthermore, seasonal influenza vaccines fail to afford protection against antigenically

  7. A single dose of inactivated hepatitis A vaccine promotes HAV-specific memory cellular response similar to that induced by a natural infection.

    Science.gov (United States)

    Melgaço, Juliana Gil; Morgado, Lucas Nóbrega; Santiago, Marta Almeida; Oliveira, Jaqueline Mendes de; Lewis-Ximenez, Lia Laura; Hasselmann, Bárbara; Cruz, Oswaldo Gonçalves; Pinto, Marcelo Alves; Vitral, Claudia Lamarca

    2015-07-31

    Based on current studies on the effects of single dose vaccines on antibody production, Latin American countries have adopted a single dose vaccine program. However, no data are available on the activation of cellular response to a single dose of hepatitis A. Our study investigated the functional reactivity of the memory cell phenotype after hepatitis A virus (HAV) stimulation through administration of the first or second dose of HAV vaccine and compared the response to that of a baseline group to an initial natural infection. Proliferation assays showed that the first vaccine dose induced HAV-specific cellular response; this response was similar to that induced by a second dose or an initial natural infection. Thus, from the first dose to the second dose, increase in the frequencies of classical memory B cells, TCD8 cells, and central memory TCD4 and TCD8 cells were observed. Regarding cytokine production, increased IL-6, IL-10, TNF, and IFNγ levels were observed after vaccination. Our findings suggest that a single dose of HAV vaccine promotes HAV-specific memory cell response similar to that induced by a natural infection. The HAV-specific T cell immunity induced by primary vaccination persisted independently of the protective plasma antibody level. In addition, our results suggest that a single dose immunization system could serve as an alternative strategy for the prevention of hepatitis A in developing countries. Copyright © 2015 Elsevier Ltd. All rights reserved.

  8. Leptospirosis vaccines

    OpenAIRE

    Jin Li; Wang Zhijun; Węgrzyn Alicja

    2007-01-01

    Abstract Leptospirosis is a serious infection disease caused by pathogenic strains of the Leptospira spirochetes, which affects not only humans but also animals. It has long been expected to find an effective vaccine to prevent leptospirosis through immunization of high risk humans or animals. Although some leptospirosis vaccines have been obtained, the vaccination is relatively unsuccessful in clinical application despite decades of research and millions of dollars spent. In this review, the...

  9. Genetically modified rabies virus ERA strain is safe and induces long-lasting protective immune response in dogs after oral vaccination.

    Science.gov (United States)

    Shuai, Lei; Feng, Na; Wang, Xijun; Ge, Jinying; Wen, Zhiyuan; Chen, Weiye; Qin, Lide; Xia, Xianzhu; Bu, Zhigao

    2015-09-01

    Oral immunization in free-roaming dogs is one of the most practical approaches to prevent rabies for developing countries. The safe, efficient and long-lasting protective oral rabies vaccine for dogs is highly sought. In this study, rabies virus (RABV) Evelyn-Rokitnicki-Abelseth (ERA) strain wild-type (rERA) and a genetically modified type (rERAG333E) containing a mutation from arginine to glutamic acid at residue 333 of glycoprotein (G333E) were generated by reverse genetic. The recombinant virus rERAG333E retained growth properties of similar to the parent strain rERA in BHK-21 cell culture. The G333E mutation showed genetic stability during passage into neuroblastoma cells and in the brains of suckling mice and was significantly reduced the virulence of rERA in mice. rERAG333E was immunogenic in dogs by intramuscular inoculation. Mice orally vaccinated with rERAG333E induced strong and one year longer virus neutralizing antibodies (VNA) to RABV, and were